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Die bedarfsgerechte Versorgung im Alter zukünftig sicherzustellen, gehört zu den entscheidenden Aufgaben unserer Zeit. Der in Deutschland bestehende Fachkräftemangel sowie der demografische Wandel belasten das Pflegesystem in mehrfacher Hinsicht: In einer alternden Gesellschaft sind immer mehr Menschen auf eine anhaltende Unterstützung angewiesen. Niedrige Geburtenraten und damit verbunden ein sinkender Bevölkerungs-anteil von Menschen im erwerbsfähigen Alter bringen einen bereits heute spürbaren Mangel an beruflich Pflegenden mit sich.
Um eine menschenwürdige Pflege anhaltend zu gewährleisten, müssen vorhandene Ressourcen gezielter eingesetzt und zusätzliche Reserven freigelegt werden. Viele Hoffnungen liegen hier auf technologischen Innovationen. Die Digitalisierung soll das Gesundheitswesen effizienter gestalten und beispielsweise durch Künstliche Intelligenz zeitraubende Prozesse vereinfachen oder sogar automatisieren. Im Kontext der Pflege wird der Einsatz von robotischen Assistenzsystemen diskutiert.
Aus diesem Grund wurde die die Potsdamer Bürger:innenkonferenz „Robotik in der Altenpflege?“ initiiert. Um die Zukunft der Pflege gemeinsam zu gestalten, wurden 3.500 Potsdamer Bürgerinnen und Bürger kontaktiert und schließlich fünfundzwanzig Teilnehmende ausgewählt. Im Frühjahr 2024 kamen sie zusammen, um den verantwortlichen Einsatz von Robotik in der Pflege zu diskutieren.
Die hier vorliegende Erklärung ist das Ergebnis der Bürger:innenkonferenz. Sie enthält die zentralen Positionen der Teilnehmenden.
Die Bürger:innenkonferenz ist Teil des Projekts E-cARE („Ethics Guidelines for Socially Assistive Robots in Elderly Care: An Empirical-Participatory Approach“), welches die Juniorprofessur für Medizinische Ethik mit Schwerpunkt auf Digitalisierung der Fakultät für Gesundheitswissenschaften Brandenburg, Universität Potsdam, durchgeführt hat.
Genome-scale metabolic models are mathematical representations of all known reactions occurring in a cell. Combined with constraints based on physiological measurements, these models have been used to accurately predict metabolic fluxes and effects of perturbations (e.g. knock-outs) and to inform metabolic engineering strategies. Recently, protein-constrained models have been shown to increase predictive potential (especially in overflow metabolism), while alleviating the need for measurement of nutrient uptake rates. The resulting modelling frameworks quantify the upkeep cost of a certain metabolic flux as the minimum amount of enzyme required for catalysis. These improvements are based on the use of in vitro turnover numbers or in vivo apparent catalytic rates of enzymes for model parameterization. In this thesis several tools for the estimation and refinement of these parameters based on in vivo proteomics data of Escherichia coli, Saccharomyces cerevisiae, and Chlamydomonas reinhardtii have been developed and applied. The difference between in vitro and in vivo catalytic rate measures for the three microorganisms was systematically analyzed. The results for the facultatively heterotrophic microalga C. reinhardtii considerably expanded the apparent catalytic rate estimates for photosynthetic organisms. Our general finding pointed at a global reduction of enzyme efficiency in heterotrophy compared to other growth scenarios. Independent of the modelled organism, in vivo estimates were shown to improve accuracy of predictions of protein abundances compared to in vitro values for turnover numbers. To further improve the protein abundance predictions, machine learning models were trained that integrate features derived from protein-constrained modelling and codon usage. Combining the two types of features outperformed single feature models and yielded good prediction results without relying on experimental transcriptomic data. The presented work reports valuable advances in the prediction of enzyme allocation in unseen scenarios using protein constrained metabolic models. It marks the first successful application of this modelling framework in the biotechnological important taxon of green microalgae, substantially increasing our knowledge of the enzyme catalytic landscape of phototrophic microorganisms.
During the last decades, therapeutical proteins have risen to great significance in the pharmaceutical industry. As non-human proteins that are introduced into the human body cause a distinct immune system reaction that triggers their rapid clearance, most newly approved protein pharmaceuticals are shielded by modification with synthetic polymers to significantly improve their blood circulation time. All such clinically approved protein-polymer conjugates contain polyethylene glycol (PEG) and its conjugation is denoted as PEGylation. However, many patients develop anti-PEG antibodies which cause a rapid clearance of PEGylated molecules upon repeated administration. Therefore, the search for alternative polymers that can replace PEG in therapeutic applications has become important. In addition, although the blood circulation time is significantly prolonged, the therapeutic activity of some conjugates is decreased compared to the unmodified protein. The reason is that these conjugates are formed by the traditional conjugation method that addresses the protein's lysine side chains. As proteins have many solvent exposed lysines, this results in a somewhat uncontrolled attachment of polymer chains, leading to a mixture of regioisomers, with some of them eventually affecting the therapeutic performance.
This thesis investigates a novel method for ligating macromolecules in a site-specific manner, using enzymatic catalysis. Sortase A is used as the enzyme: It is a well-studied transpeptidase which is able to catalyze the intermolecular ligation of two peptides. This process is commonly referred to as sortase-mediated ligation (SML). SML constitutes an equilibrium reaction, which limits product yield. Two previously reported methods to overcome this major limitation were tested with polymers without using an excessive amount of one reactant.
Specific C- or N-terminal peptide sequences (recognition sequence and nucleophile) as part of the protein are required for SML. The complementary peptide was located at the polymer chain end. Grafting-to was used to avoid damaging the protein during polymerization. To be able to investigate all possible combinations (protein-recognition sequence and nucleophile-protein as well as polymer-recognition sequence and nucleophile-polymer) all necessary building blocks were synthesized. Polymerization via reversible deactivation radical polymerization (RDRP) was used to achieve a narrow molecular weight distribution of the polymers, which is required for therapeutic use.
The synthesis of the polymeric building blocks was started by synthesizing the peptide via automated solid-phase peptide synthesis (SPPS) to avoid post-polymerization attachment and to enable easy adaptation of changes in the peptide sequence. To account for the different functionalities (free N- or C-terminus) required for SML, different linker molecules between resin and peptide were used.
To facilitate purification, the chain transfer agent (CTA) for reversible addition-fragmentation chain-transfer (RAFT) polymerization was coupled to the resin-immobilized recognition sequence peptide. The acrylamide and acrylate-based monomers used in this thesis were chosen for their potential to replace PEG.
Following that, surface-initiated (SI) ATRP and RAFT polymerization were attempted, but failed. As a result, the newly developed method of xanthate-supported photo-iniferter (XPI) RAFT polymerization in solution was used successfully to obtain a library of various peptide-polymer conjugates with different chain lengths and narrow molar mass distributions.
After peptide side chain deprotection, these constructs were used first to ligate two polymers via SML, which was successful but revealed a limit in polymer chain length (max. 100 repeat units). When utilizing equimolar amounts of reactants, the use of Ni2+ ions in combination with a histidine after the recognition sequence to remove the cleaved peptide from the equilibrium maximized product formation with conversions of up to 70 %.
Finally, a model protein and a nanobody with promising properties for therapeutical use were biotechnologically modified to contain the peptide sequences required for SML. Using the model protein for C- or N-terminal SML with various polymers did not result in protein-polymer conjugates. The reason is most likely the lack of accessibility of the protein termini to the enzyme. Using the nanobody for C-terminal SML, on the other hand, was successful. However, a similar polymer chain length limit was observed as in polymer-polymer SML. Furthermore, in case of the synthesis of protein-polymer conjugates, it was more effective to shift the SML equilibrium by using an excess of polymer than by employing the Ni2+ ion strategy.
Overall, the experimental data from this work provides a good foundation for future research in this promising field; however, more research is required to fully understand the potential and limitations of using SML for protein-polymer synthesis. In future, the method explored in this dissertation could prove to be a very versatile pathway to obtain therapeutic protein-polymer conjugates that exhibit high activities and long blood circulation times.
Zum dreißigjährigen Bestehen des Kommunalwissenschaftlichen Instituts an der Universität Potsdam vereint dieser Jubiläumsband kurze Aufsätze von ehemaligen und aktuellen Vorstandsmitgliedern, von Ehrenmitgliedern des Vorstands, langjährigen wissenschaftlichen Mitarbeitern des Instituts und aktuellen wissenschaftlichen Kooperationspartnern. Die insgesamt zwölf Beiträge befassen sich mit den Kommunalwissenschaften und der Geschichte des Kommunalwissenschaftlichen Instituts, mit aktuellen kommunalwissenschaftlichen Fragestellungen und wissenschaftlichen Kooperationen des KWI. Der vom KWI-Vorstand herausgegebene Band soll einen breiten Blick auf 30 Jahre Kommunalwissenschaften in Brandenburg und an der Universität Potsdam werfen und einen Ausblick auf zukünftige kommunalwissenschaftliche Forschung geben.
We analyze how conventional emissions trading schemes (ETS) can be modified by introducing “clean-up certificates” to allow for a phase of net-negative emissions. Clean-up certificates bundle the permission to emit CO2 with the obligation for its removal. We show that demand for such certificates is determined by cost-saving technological progress, the discount rate and the length of the compliance period. Introducing extra clean-up certificates into an existing ETS reduces near-term carbon prices and mitigation efforts. In contrast, substituting ETS allowances with clean-up certificates reduces cumulative emissions without depressing carbon prices or mitigation in the near term. We calibrate our model to the EU ETS and identify reforms where simultaneously (i) ambition levels rise, (ii) climate damages fall, (iii) revenues from carbon prices rise and (iv) carbon prices and aggregate mitigation cost fall. For reducing climate damages, roughly half of the issued clean-up certificates should replace conventional ETS allowances. In the context of the EU ETS, a European Carbon Central Bank could manage the implementation of cleanup certificates and could serve as an enforcement mechanism.
Das Forschungsprojekt „Workflow-Management-Systeme für Open-Access-Hochschulverlage (OA-WFMS)” ist eine Kooperation zwischen der HTWK Leipzig und der Universität Potsdam. Ziel ist es, die Bedarfe von Universitäts- und Hochschulverlagen und Anforderungen an ein Workflow-Management-Systeme (WFMS) zu analysieren, um daraus ein generisches Lastenheft zu erstellen. Das WFMS soll den Publikationsprozess in OA-Verlagen erleichtern, beschleunigen sowie die Verbreitung von Open Access und das nachhaltige, digitale wissenschaftliche Publizieren fördern.
Das Projekt baut auf den Ergebnissen der Projekte „Open-Access-Hochschulverlag (OA-HVerlag)“ und „Open-Access-Strukturierte-Kommunikation (OA-STRUKTKOMM)“ auf. Der diesem Bericht zugrunde liegende Auftaktworkshop fand 2024 in Leipzig mit Vertreter:innen von zehn Institutionen statt. Der Workshop diente dazu, Herausforderungen und Anforderungen an ein WFMS zu ermitteln sowie bestehende Lösungsansätze und Tools zu diskutieren.
Im Workshop wurden folgende Fragen behandelt:
a. Wie kann die Organisation und Überwachung von Publikationsprozessen in wissenschaftlichen Verlagen durch ein WFMS effizient gestaltet werden?
b. Welche Anforderungen muss ein WFMS erfüllen, um Publikationsprozesse optimal zu unterstützen?
c. Welche Schnittstellen müssen berücksichtigt werden, um die Interoperabilität der Systeme zu garantieren?
d. Welche bestehenden Lösungsansätze und Tools sind bereits im Einsatz und welche Vor- und Nachteile haben diese?
Der Workshop gliederte sich in zwei Teile : Teil 1 behandelte Herausforderungen und Anforderungen (Fragen a. bis c.), Teil 2 bestehende Lösungen und Tools (Frage d.). Die Ergebnisse des Workshops fließen in die Bedarfsanalyse des Forschungsprojekts ein.
Die im Bericht dokumentierten Ergebnisse zeigen die Vielzahl der Herausforderungen der bestehenden Ansätze bezüglich des OA-Publikationsmanagements . Die Herausforderungen zeigen sich insbesondere bei der Systemheterogenität, den individuellen Anpassungsbedarfen und der Notwendigkeit der systematischen Dokumentation. Die eingesetzten Unterstützungssysteme und Tools wie Dateiablagen, Projektmanagement- und Kommunikationstools können insgesamt den Anforderungen nicht genügen, für Teillösungen sind sie jedoch nutzbar. Deshalb muss die Integration bestehender Systeme in ein zu entwickelndes OA-WFMS in Betracht gezogen und die Interoperabilität der miteinander interagierenden Systeme gewährleistet werden. Die Beteiligten des Workshops waren sich einig, dass das OA-WFMS flexibel und modular aufgebaut werden soll. Einer konsortialen Softwareentwicklung und einem gemeinsamen Betrieb im Verbund wurde der Vorrang gegeben.
Der Workshop lieferte wertvolle Einblicke in die Arbeit der Hochschulverlage und bildet somit eine solide Grundlage für die in Folge zu erarbeitende weitere Bedarfsanalyse und die Erstellung des generischen Lastenheftes.
We study the effect of energy and transport policies on pollution in two developing country cities. We use a quantitative equilibrium model with choice of housing, energy use, residential location, transport mode, and energy technology. Pollution comes from commuting and residential energy use. The model parameters are calibrated to replicate key variables for two developing country cities, Maputo, Mozambique, and Yogyakarta, Indonesia. In the counterfactual simulations, we study how various transport and energy policies affect equilibrium pollution. Policies may be induce rebound effects from increasing residential energy use or switching to high emission modes or locations. In general, these rebound effects tend to be largest for subsidies to public transport or modern residential energy technology.
We examine how the gender of business-owners is related to the wages paid to female relative to male employees working in their firms. Using Finnish register data and employing firm fixed effects, we find that the gender pay gap is – starting from a gender pay gap of 11 to 12 percent - two to three percentage-points lower for hourly wages in female-owned firms than in male-owned firms. Results are robust to how the wage is measured, as well as to various further robustness checks. More importantly, we find substantial differences between industries. While, for instance, in the manufacturing sector, the gender of the owner plays no role for the gender pay gap, in several service sector industries, like ICT or business services, no or a negligible gender pay gap can be found, but only when firms are led by female business owners. Businesses in male ownership maintain a gender pay gap of around 10 percent also in the latter industries. With increasing firm size, the influence of the gender of the owner, however, fades. In large firms, it seems that others – firm managers – determine wages and no differences in the pay gap are observed between male- and female-owned firms.
The Arctic is the hot spot of the ongoing, global climate change. Over the last decades, near-surface temperatures in the Arctic have been rising almost four times faster than on global average. This amplified warming of the Arctic and the associated rapid changes of its environment are largely influenced by interactions between individual components of the Arctic climate system. On daily to weekly time scales, storms can have major impacts on the Arctic sea-ice cover and are thus an important part of these interactions within the Arctic climate. The sea-ice impacts of storms are related to high wind speeds, which enhance the drift and deformation of sea ice, as well as to changes in the surface energy budget in association with air mass advection, which impact the seasonal sea-ice growth and melt.
The occurrence of storms in the Arctic is typically associated with the passage of transient cyclones. Even though the above described mechanisms how storms/cyclones impact the Arctic sea ice are in principal known, there is a lack of statistical quantification of these effects. In accordance with that, the overarching objective of this thesis is to statistically quantify cyclone impacts on sea-ice concentration (SIC) in the Atlantic Arctic Ocean over the last four decades. In order to further advance the understanding of the related mechanisms, an additional objective is to separate dynamic and thermodynamic cyclone impacts on sea ice and assess their relative importance. Finally, this thesis aims to quantify recent changes in cyclone impacts on SIC. These research objectives are tackled utilizing various data sets, including atmospheric and oceanic reanalysis data as well as a coupled model simulation and a cyclone tracking algorithm.
Results from this thesis demonstrate that cyclones are significantly impacting SIC in the Atlantic Arctic Ocean from autumn to spring, while there are mostly no significant impacts in summer. The strength and the sign (SIC decreasing or SIC increasing) of the cyclone impacts strongly depends on the considered daily time scale and the region of the Atlantic Arctic Ocean. Specifically, an initial decrease in SIC (day -3 to day 0 relative to the cyclone) is found in the Greenland, Barents and Kara Seas, while SIC increases following cyclones (day 0 to day 5 relative to the cyclone) are mostly limited to the Barents and Kara Seas.
For the cold season, this results in a pronounced regional difference between overall (day -3 to day 5 relative to the cyclone) SIC-decreasing cyclone impacts in the Greenland Sea and overall SIC-increasing cyclone impacts in the Barents and Kara Seas. A cyclone case study based on a coupled model simulation indicates that both dynamic and thermodynamic mechanisms contribute to cyclone impacts on sea ice in winter. A typical pattern consisting of an initial dominance of dynamic sea-ice changes followed by enhanced thermodynamic ice growth after the cyclone passage was found. This enhanced ice growth after the cyclone passage most likely also explains the (statistical) overall SIC-increasing effects of cyclones in the Barents and Kara Seas in the cold season.
Significant changes in cyclone impacts on SIC over the last four decades have emerged throughout the year. These recent changes are strongly varying from region to region and month to month. The strongest trends in cyclone impacts on SIC are found in autumn in the Barents and Kara Seas. Here, the magnitude of destructive cyclone impacts on SIC has approximately doubled over the last four decades. The SIC-increasing effects following the cyclone passage have particularly weakened in the Barents Sea in autumn. As a consequence, previously existing overall SIC-increasing cyclone impacts in this region in autumn have recently disappeared. Generally, results from this thesis show that changes in the state of the sea-ice cover (decrease in mean sea-ice concentration and thickness) and near-surface air temperature are most important for changed cyclone impacts on SIC, while changes in cyclone properties (i.e. intensity) do not play a significant role.
Aging is associated with bone loss, which can lead to osteoporosis and high fracture risk. This coincides with the enhanced formation of bone marrow adipose tissue (BMAT), suggesting a negative effect of bone marrow adipocytes on skeletal health. Increased BMAT formation is also observed in pathologies such as obesity, type 2 diabetes and osteoporosis. However, a subset of bone marrow adipocytes forming the constitutive BMAT (cBMAT), arise early in life in the distal skeleton, contain high levels of unsaturated fatty acids and are thought to provide a physiological function. Regulated BMAT (rBMAT) forms during aging and obesity in proximal regions of the bone and contain a large proportion of saturated fatty acids. Paradoxically, BMAT accumulation is also enhanced during caloric restriction (CR), a life-span extending dietary intervention. This indicates, that different types of BMAT can form in response to opposing nutritional stimuli with potentially different functions.
To this end, two types of nutritional interventions, CR and high fat diet (HFD), that are both described to induce BMAT accumulation were carried out. CR markedly increased BMAT formation in the proximal tibia and led to a higher proportion of unsaturated fatty acids, making it similar to the physiological cBMAT. Additionally, proximal and diaphyseal tibia regions displayed higher adiponectin expression. In aged mice, CR was associated with an improved trabecular bone structure. Taken together, these findings demonstrate, that the type of BMAT that forms during CR might provide beneficial effects for local bone stem/progenitor cells and metabolic health. The HFD intervention performed in this thesis showed no effect on BMAT accumulation and bone microstructure. RNA Seq analysis revealed alterations in the composition of the collagen-containing extracellular matrix (ECM).
In order to investigate the effects of glucose homeostasis on osteogenesis, differentiation capacity of immortalized multipotent mesenchymal stromal cells (MSCs) and osteochondrogenic progenitor cells (OPCs) was analyzed. Insulin improved differentiation in both cell types, however, combination of with a high glucose concentration led to an impaired mineralization of the ECM. In the MSCs, this was accompanied by the formation of adipocytes, indicating negative effects of the adipocytes formed during hyperglycemic conditions on mineralization processes. However, the altered mineralization pattern and structure of the ECM was also observed in OPCs, which did not form any adipocytes, suggesting further negative effects of a hyperglycemic environment on osteogenic differentiation.
In summary, the work provided in this thesis demonstrated that differentiation commitment of bone-resident stem cells can be altered through nutrient availability, specifically glucose. Surprisingly, both high nutrient supply, e.g. the hyperglycemic cell culture conditions, and low nutrient supply, e.g. CR, can induce adipogenic differentiation. However, while CR-induced adipocyte formation was associated with improved trabecular bone structure, adipocyte formation in a hyperglycemic cell-culture environment hampered mineralization. This thesis provides further evidence for the existence of different types of BMAT with specific functions.
Schulpraktische Phasen stellen eine bedeutende praxisnahe Lerngelegenheit im Lehramtsstudium dar, da sie Raum für umfangreiche Reflexionen der eigenen Lernerfahrung bieten. Das im Studium erworbene theoretisch-formale Wissen steht hierbei dem praktischen Wissen und Können gegenüber. Mit der professionellen Entwicklung im Referendariat, besonders im Kompetenzbereich des Unterrichtens, kann geschlussfolgert werden, dass sich eine Reflexion über eher fachliche Aspekte unter den Studierenden im Referendariat auf eine Reflexion über eher überfachliche und pädagogische Aspekte weitet. Infolge der Analyse von N = 55 schriftlichen Fremdreflexionen von angehenden Physiklehrkräften aus Studium und Referendariat konnte diese Hypothese für den Bereich der Unterrichtsanalyse und -reflexion unterstützt werden. Weiter wurde aus der Videovignette ein Workshopangebot für Lehrkräfte der zweiten und dritten Phase der Lehrkräftebildung entwickelt, erprobt und evaluiert.
Die Fachausbildung des Vorbereitungsdiensts im Land Brandenburg bietet Lehramtskandidat:innen (LAK) gemeinsame Fachgruppenarbeit, individuelle Fachkonsultationen sowie Hospitationen als unterstützende Angebote im Entwicklungsprozess. Um diesen Professionalisierungsprozess sichtbar zu machen und Zielperspektiven entwickeln und verfolgen zu können, wurden aus einem Spinnennetzdiagramm zwei Praxistools zur Reflexion und Diagnose entwickelt.
(1) Reflexionstool: Die Übertragung eines tabellarischen Kompetenzprofils (Arnold & Iffert nach MBJS [Ministerium für Bildung, Jugend und Sport des Landes Brandenburg], 2014) in das Spinnennetzdiagramm bietet den LAK niederschwellige Gelegenheit der kontinuierlichen, prozessbegleitenden Selbstreflexion. Die Selbstwahrnehmung von positiven Entwicklungen kann zur Stärkung der Selbstwirksamkeit führen, schafft gleichzeitig jedoch eine Bewusstmachung für einzelne Herausforderungen. Die Abbildung individueller Entwicklungsaufgaben und Professionalisierungsbedarfe ermöglicht eine bedarfsorientierte Gestaltung der Fachgruppenarbeit.
(2) Diagnosetool: Analog wird Fachausbilder:innen durch die Übertragung der Beobachtungskriterien des MBJS (2014) in das Diagramm eine übersichtliche Bestandsaufnahme einzelner Unterrichtssituationen zur Diagnose von Grundkoordinaten des Unterrichts transparent. Auf diese Weise können Fachausbilder:innen mögliche blinde Flecken identifizieren und Feedback zur Auswahl von Beobachtungskriterien geben. Darüber hinaus ergeben sich Aspekte zur Gestaltung von Fachkonsultationen sowie Diskussionsgrundlagen für Gruppenhospitationen.
The increasing number of known exoplanets raises questions about their demographics and the mechanisms that shape planets into how we observe them today. Young planets in close-in orbits are exposed to harsh environments due to the host star being magnetically highly active, which results in high X-ray and extreme UV fluxes impinging on the planet. Prolonged exposure to this intense photoionizing radiation can cause planetary atmospheres to heat up, expand and escape into space via a hydrodynamic escape process known as photoevaporation. For super-Earth and sub-Neptune-type planets, this can even lead to the complete erosion of their primordial gaseous atmospheres. A factor of interest for this particular mass-loss process is the activity evolution of the host star. Stellar rotation, which drives the dynamo and with it the magnetic activity of a star, changes significantly over the stellar lifetime. This strongly affects the amount of high-energy radiation received by a planet as stars age. At a young age, planets still host warm and extended envelopes, making them particularly susceptible to atmospheric evaporation. Especially in the first gigayear, when X-ray and UV levels can be 100 - 10,000 times higher than for the present-day sun, the characteristics of the host star and the detailed evolution of its high-energy emission are of importance.
In this thesis, I study the impact of stellar activity evolution on the high-energy-induced atmospheric mass loss of young exoplanets. The PLATYPOS code was developed as part of this thesis to calculate photoevaporative mass-loss rates over time. The code, which couples parameterized planetary mass-radius relations with an analytical hydrodynamic escape model, was used, together with Chandra and eROSITA X-ray observations, to investigate the future mass loss of the two young multiplanet systems V1298 Tau and K2-198. Further, in a numerical ensemble study, the effect of a realistic spread of activity tracks on the small-planet radius gap was investigated for the first time. The works in this thesis show that for individual systems, in particular if planetary masses are unconstrained, the difference between a young host star following a low-activity track vs. a high-activity one can have major implications: the exact shape of the activity evolution can determine whether a planet can hold on to some of its atmosphere, or completely loses its envelope, leaving only the bare rocky core behind. For an ensemble of simulated planets, an observationally-motivated distribution of activity tracks does not substantially change the final radius distribution at ages of several gigayears. My simulations indicate that the overall shape and slope of the resulting small-planet radius gap is not significantly affected by the spread in stellar activity tracks. However, it can account for a certain scattering or fuzziness observed in and around the radius gap of the observed exoplanet population.
The icosahedral non-hydrostatic large eddy model (ICON-LEM) was applied around the drift track of the Multidisciplinary Observatory Study of the Arctic (MOSAiC) in 2019 and 2020. The model was set up with horizontal grid-scales between 100m and 800m on areas with radii of 17.5km and 140 km. At its lateral boundaries, the model was driven by analysis data from the German Weather Service (DWD), downscaled by ICON in limited area mode (ICON-LAM) with horizontal grid-scale of 3 km.
The aim of this thesis was the investigation of the atmospheric boundary layer near the surface in the central Arctic during polar winter with a high-resolution mesoscale model. The default settings in ICON-LEM prevent the model from representing the exchange processes in the Arctic boundary layer in accordance to the MOSAiC observations. The implemented sea-ice scheme in ICON does not include a snow layer on sea-ice, which causes a too slow response of the sea-ice surface temperature to atmospheric changes. To allow the sea-ice surface to respond faster to changes in the atmosphere, the implemented sea-ice parameterization in ICON was extended with an adapted heat capacity term.
The adapted sea-ice parameterization resulted in better agreement with the MOSAiC observations. However, the sea-ice surface temperature in the model is generally lower than observed due to biases in the downwelling long-wave radiation and the lack of complex surface structures, like leads. The large eddy resolving turbulence closure yielded a better representation of the lower boundary layer under strongly stable stratification than the non-eddy-resolving turbulence closure. Furthermore, the integration of leads into the sea-ice surface reduced the overestimation of the sensible heat flux for different weather conditions.
The results of this work help to better understand boundary layer processes in the central Arctic during the polar night. High-resolving mesoscale simulations are able to represent temporally and spatially small interactions and help to further develop parameterizations also for the application in regional and global models.
With Arctic ground as a huge and temperature-sensitive carbon reservoir, maintaining low ground temperatures and frozen conditions to prevent further carbon emissions that contrib-ute to global climate warming is a key element in humankind’s fight to maintain habitable con-ditions on earth. Former studies showed that during the late Pleistocene, Arctic ground condi-tions were generally colder and more stable as the result of an ecosystem dominated by large herbivorous mammals and vast extents of graminoid vegetation – the mammoth steppe. Characterised by high plant productivity (grassland) and low ground insulation due to animal-caused compression and removal of snow, this ecosystem enabled deep permafrost aggrad-ation. Now, with tundra and shrub vegetation common in the terrestrial Arctic, these effects are not in place anymore. However, it appears to be possible to recreate this ecosystem local-ly by artificially increasing animal numbers, and hence keep Arctic ground cold to reduce or-ganic matter decomposition and carbon release into the atmosphere.
By measuring thaw depth, total organic carbon and total nitrogen content, stable carbon iso-tope ratio, radiocarbon age, n-alkane and alcohol characteristics and assessing dominant vegetation types along grazing intensity transects in two contrasting Arctic areas, it was found that recreating conditions locally, similar to the mammoth steppe, seems to be possible. For permafrost-affected soil, it was shown that intensive grazing in direct comparison to non-grazed areas reduces active layer depth and leads to higher TOC contents in the active layer soil. For soil only frozen on top in winter, an increase of TOC with grazing intensity could not be found, most likely because of confounding factors such as vertical water and carbon movement, which is not possible with an impermeable layer in permafrost. In both areas, high animal activity led to a vegetation transformation towards species-poor graminoid-dominated landscapes with less shrubs. Lipid biomarker analysis revealed that, even though the available organic material is different between the study areas, in both permafrost-affected and sea-sonally frozen soils the organic material in sites affected by high animal activity was less de-composed than under less intensive grazing pressure. In conclusion, high animal activity af-fects decomposition processes in Arctic soils and the ground thermal regime, visible from reduced active layer depth in permafrost areas. Therefore, grazing management might be utilised to locally stabilise permafrost and reduce Arctic carbon emissions in the future, but is likely not scalable to the entire permafrost region.
Large parts of the Earth’s interior are inaccessible to direct observation, yet global geodynamic processes are governed by the physical material properties under extreme pressure and temperature conditions. It is therefore essential to investigate the deep Earth’s physical properties through in-situ laboratory experiments. With this goal in mind, the optical properties of mantle minerals at high pressure offer a unique way to determine a variety of physical properties, in a straight-forward, reproducible, and time-effective manner, thus providing valuable insights into the physical processes of the deep Earth. This thesis focusses on the system Mg-Fe-O, specifically on the optical properties of periclase (MgO) and its iron-bearing variant ferropericlase ((Mg,Fe)O), forming a major planetary building block. The primary objective is to establish links between physical material properties and optical properties. In particular the spin transition in ferropericlase, the second-most abundant phase of the lower mantle, is known to change the physical material properties. Although the spin transition region likely extends down to the core-mantle boundary, the ef-fects of the mixed-spin state, where both high- and low-spin state are present, remains poorly constrained.
In the studies presented herein, we show how optical properties are linked to physical properties such as electrical conductivity, radiative thermal conductivity and viscosity. We also show how the optical properties reveal changes in the chemical bonding. Furthermore, we unveil how the chemical bonding, the optical and other physical properties are affected by the iron spin transition. We find opposing trends in the pres-sure dependence of the refractive index of MgO and (Mg,Fe)O. From 1 atm to ~140 GPa, the refractive index of MgO decreases by ~2.4% from 1.737 to 1.696 (±0.017). In contrast, the refractive index of (Mg0.87Fe0.13)O (Fp13) and (Mg0.76Fe0.24)O (Fp24) ferropericlase increases with pressure, likely because Fe Fe interactions between adjacent iron sites hinder a strong decrease of polarizability, as it is observed with increasing density in the case of pure MgO. An analysis of the index dispersion in MgO (decreasing by ~23% from 1 atm to ~103 GPa) reflects a widening of the band gap from ~7.4 eV at 1 atm to ~8.5 (±0.6) eV at ~103 GPa. The index dispersion (between 550 and 870 nm) of Fp13 reveals a decrease by a factor of ~3 over the spin transition range (~44–100 GPa). We show that the electrical band gap of ferropericlase significantly widens up to ~4.7 eV in the mixed spin region, equivalent to an increase by a factor of ~1.7. We propose that this is due to a lower electron mobility between adjacent Fe2+ sites of opposite spin, explaining the previously observed low electrical conductivity in the mixed spin region. From the study of absorbance spectra in Fp13, we show an increasing covalency of the Fe-O bond with pressure for high-spin ferropericlase, whereas in the low-spin state a trend to a more ionic nature of the Fe-O bond is observed, indicating a bond weakening effect of the spin transition. We found that the spin transition is ultimately caused by both an increase of the ligand field-splitting energy and a decreasing spin-pairing energy of high-spin Fe2+.
Leadership plays an important role for the efficient and fair solution of social dilemmas but the effectiveness of a leader can vary substantially. Two main factors of leadership impact are the ability to induce high contributions by all group members and the (expected) fair use of power. Participants in our experiment decide about contributions to a public good. After all contributions are made, the leader can choose how much of the joint earnings to assign to herself; the remainder is distributed equally among the followers. Using machine learning techniques, we study whether the content of initial open statements by the group members predicts their behavior as a leader and whether groups are able to identify such clues and endogenously appoint a “good” leader to solve the dilemma. We find that leaders who promise fairness are more likely to behave fairly, and that followers appoint as leaders those who write more explicitly about fairness and efficiency. However, in their contribution decision, followers focus on the leader’s first-move contribution and place less importance on the content of the leader’s statements.
Access to digital finance
(2024)
Financing entrepreneurship spurs innovation and economic growth. Digital financial platforms that crowdfund equity for entrepreneurs have emerged globally, yet they remain poorly understood. We model equity crowdfunding in terms of the relationship between the number of investors and the amount of money raised per pitch. We examine heterogeneity in the average amount raised per pitch that is associated with differences across three countries and seven platforms. Using a novel dataset of successful fundraising on the most prominent platforms in the UK, Germany, and the USA, we find the underlying relationship between the number of investors and the amount of money raised for entrepreneurs is loglinear, with a coefficient less than one and concave to the origin. We identify significant variation in the average amount invested in each pitch across countries and platforms. Our findings have implications for market actors as well as regulators who set competitive frameworks.
Earthquake modeling is the key to a profound understanding of a rupture. Its kinematics or dynamics are derived from advanced rupture models that allow, for example, to reconstruct the direction and velocity of the rupture front or the evolving slip distribution behind the rupture front. Such models are often parameterized by a lattice of interacting sub-faults with many degrees of freedom, where, for example, the time history of the slip and rake on each sub-fault are inverted. To avoid overfitting or other numerical instabilities during a finite-fault estimation, most models are stabilized by geometric rather than physical constraints such as smoothing.
As a basis for the inversion approach of this study, we build on a new pseudo-dynamic rupture model (PDR) with only a few free parameters and a simple geometry as a physics-based solution of an earthquake rupture. The PDR derives the instantaneous slip from a given stress drop on the fault plane, with boundary conditions on the developing crack surface guaranteed at all times via a boundary element approach. As a side product, the source time function on each point on the rupture plane is not constraint and develops by itself without additional parametrization. The code was made publicly available as part of the Pyrocko and Grond Python packages. The approach was compared with conventional modeling for different earthquakes. For example, for the Mw 7.1 2016 Kumamoto, Japan, earthquake, the effects of geometric changes in the rupture surface on the slip and slip rate distributions could be reproduced by simply projecting stress vectors. For the Mw 7.5 2018 Palu, Indonesia, strike-slip earthquake, we also modelled rupture propagation using the 2D Eikonal equation and assuming a linear relationship between rupture and shear wave velocity. This allowed us to give a deeper and faster propagating rupture front and the resulting upward refraction as a new possible explanation for the apparent supershear observed at the Earth's surface.
The thesis investigates three aspects of earthquake inversion using PDR: (1) to test whether implementing a simplified rupture model with few parameters into a probabilistic Bayesian scheme without constraining geometric parameters is feasible, and whether this leads to fast and robust results that can be used for subsequent fast information systems (e.g., ground motion predictions). (2) To investigate whether combining broadband and strong-motion seismic records together with near-field ground deformation data improves the reliability of estimated rupture models in a Bayesian inversion. (3) To investigate whether a complex rupture can be represented by the inversion of multiple PDR sources and for what type of earthquakes this is recommended.
I developed the PDR inversion approach and applied the joint data inversions to two seismic sequences in different tectonic settings. Using multiple frequency bands and a multiple source inversion approach, I captured the multi-modal behaviour of the Mw 8.2 2021 South Sandwich subduction earthquake with a large, curved and slow rupturing shallow earthquake bounded by two faster and deeper smaller events. I could cross-validate the results with other methods, i.e., P-wave energy back-projection, a clustering analysis of aftershocks and a simple tsunami forward model.
The joint analysis of ground deformation and seismic data within a multiple source inversion also shed light on an earthquake triplet, which occurred in July 2022 in SE Iran. From the inversion and aftershock relocalization, I found indications for a vertical separation between the shallower mainshocks within the sedimentary cover and deeper aftershocks at the sediment-basement interface. The vertical offset could be caused by the ductile response of the evident salt layer to stress perturbations from the mainshocks.
The applications highlight the versatility of the simple PDR in probabilistic seismic source inversion capturing features of rather different, complex earthquakes. Limitations, as the evident focus on the major slip patches of the rupture are discussed as well as differences to other finite fault modeling methods.
Properties of Arctic aerosol in the transition between Arctic haze to summer season derived by lidar
(2023)
During the Arctic haze period, the Arctic troposphere consists of larger, yet fewer, aerosol particles than during the summer (Tunved et al., 2013; Quinn et al., 2007). Interannual variability (Graßl and Ritter, 2019; Rinke et al., 2004), as well as unknown origins (Stock et al., 2014) and properties of aerosol complicate modeling these annual aerosol cycles. This thesis investigates the modification of the microphysical properties of Arctic aerosols in the transition from Arctic haze to the summer season. Therefore, lidar measurements of Ny-Ålesund from April 2021 to the end of July 2021 are evaluated based on the aerosols’ optical properties. An overview of those properties will be provided. Furthermore, parallel radiosonde data is considered for indication of hygroscopic growth.
The annual aerosol cycle in 2021 differs from expectations based on previous studies from Tunved et al. (2013) and Quinn et al. (2007). Developments of backscatter, extinction, aerosol depolarisation, lidar ratio and color ratio show a return of the Arctic haze in May. The haze had already reduced in April, but regrew afterwards.
The average Arctic aerosol displays hygroscopic behaviour, meaning growth due to water uptake. To determine such a behaviour is generally laborious because various meteorological circumstances need to be considered. Two case studies provide further information on these possible events. In particular, a day with a rare ice cloud and with highly variable water cloud layers is observed.
Zentrale Aufgaben von Kommunen in Deutschland umfassen die Gewährleistung der Daseinsvorsorge, des öffentlichen Verkehrs, Wirtschaftsförderung, Zugang zu ausreichender Breitbandinfrastruktur, gesundheitliche und soziale Betreuung und Zugang zu kulturellem Leben. Kommunen in ländlichen Regionen stehen gleichzeitig vor zahlreichen gesellschaftlichen, wirtschaftlichen, sozialen und politischen Herausforderungen. Neuartige Ansätze und innovative Akteure und Netzwerke werden daher im Kontext der Schaffung von sozialen oder digitalen Innovationen von den Kommunen als Antwort auf diese Herausforderungen begrüßt, stoßen aber auch teilweise auf Barrieren.
In dem Sammelband wird von den Herausgebenden die Frage untersucht, wie sich digitale Vorreiter:innen, die wir „Digitale Pioniere“ nennen, in ländlichen Regionen vernetzen, um einen positiven Beitrag zur ländlichen Regionalentwicklung zu leisten. Dabei liegt der Fokus hauptsächlich auf der kommunalpolitischen Ebene und auf der Frage, wie Digitale Pioniere als Schlüsselakteure in der ländlichen Governance agieren. Die Forschungsergebnisse kommunaler Governance sind anhand ländlicher Untersuchungsteilregionen in Baden-Württemberg und Mecklenburg-Vorpommern im Rahmen des Forschungsprojekts „DigPion – Digitale Pioniere in der ländlichen Regionalentwicklung“ (2020–2023) erarbeitet worden. Abschließend wird überprüft, wie die Erkenntnisse und erarbeiteten Handlungsempfehlungen für das Bundesland Brandenburg zu übertragen sind.
Reflexion – unhinterfragt eines der wichtigsten Worte im Kontext der Lehrkräftebildung. Fest verankert in den bundesdeutschen Bildungsstandards sind in Forschung und Lehre die Suche nach Evidenz und die Unterstützung (angehender) Lehrkräfte ständiger Antrieb unzähliger Akteur:innen aller Phasen der Lehrkräftebildung. Wenngleich begriff liche Unklarheiten die Kommunikation von Forschungsergebnissen nicht immer intuitiv und die Unterstützung in der Lehre nicht immer praktikabel werden lassen, besteht Einigkeit darüber, dass ein Diskurs zur reflexiven Professionalisierung von Lehrkräften geführt werden muss. Aus diesem Grund veranstalteten die beiden QLB-Projekte PSI-Potsdam der Universität Potsdam und K2teach der Freien Universität Berlin vom 5. bis 7. Oktober 2022 die Onlinetagung „Reflexion in der Lehrkräftebildung. Empirisch – Phasenübergreifend – Interdisziplinär“. Ausgehend von den verschiedensten Fachdisziplinen diskutierten Akteur:innen aller Phasen der Lehrkräftebildung unterschiedlicher Standorte Ergebnisse empirischer Studien und Erfahrungen aus der Arbeit mit (angehenden) Lehrkräften. Beiträge der Tagung sind in diesem Buch festgehalten und sind als Momentaufnahme eines sich ständig entwickelnden Themenfelds zu verstehen. Forschende und Lehrende haben mit dieser Momentaufnahme die Möglichkeit, Eindrücke für die eigene Arbeit aufzunehmen und weiterzuentwickeln.
In the present thesis, AC electrokinetic forces, like dielectrophoresis and AC electroosmosis, were demonstrated as a simple and fast method to functionalize the surface of nanoelectrodes with submicrometer sized biological objects. These nanoelectrodes have a cylindrical shape with a diameter of 500 nm arranged in an array of 6256 electrodes. Due to its medical relevance influenza virus as well as anti-influenza antibodies were chosen as a model organism. Common methods to bring antibodies or proteins to biosensor surfaces are complex and time-consuming. In the present work, it was demonstrated that by applying AC electric fields influenza viruses and antibodies can be immobilized onto the nanoelectrodes within seconds without any prior chemical modification of neither the surface nor the immobilized biological object. The distribution of these immobilized objects is not uniform over the entire array, it exhibits a decreasing gradient from the outer row to the inner ones. Different causes for this gradient have been discussed, such as the vortex-shaped fluid motion above the nanoelectrodes generated by, among others, electrothermal fluid flow. It was demonstrated that parts of the accumulated material are permanently immobilized to the electrodes. This is a unique characteristic of the presented system since in the literature the AC electrokinetic immobilization is almost entirely presented as a method just for temporary immobilization. The spatial distribution of the immobilized viral material or the anti-influenza antibodies at the electrodes was observed by either the combination of fluorescence microscopy and deconvolution or by super-resolution microscopy (STED). On-chip immunoassays were performed to examine the suitability of the functionalized electrodes as a potential affinity-based biosensor. Two approaches were pursued: A) the influenza virus as the bio-receptor or B) the influenza virus as the analyte. Different sources of error were eliminated by ELISA and passivation experiments. Hence, the activity of the immobilized object was inspected by incubation with the analyte. This resulted in the successful detection of anti-influenza antibodies by the immobilized viral material. On the other hand, a detection of influenza virus particles by the immobilized anti-influenza antibodies was not possible. The latter might be due to lost activity or wrong orientation of the antibodies. Thus, further examinations on the activity of by AC electric fields immobilized antibodies should follow. When combined with microfluidics and an electrical read-out system, the functionalized chips possess the potential to serve as a rapid, portable, and cost-effective point-of-care (POC) device. This device can be utilized as a basis for diverse applications in diagnosing and treating influenza, as well as various other pathogens.
Im Rahmen des PSI-Projekts wurde eine Lehrveranstaltung konzipiert, die Lehramtsstudierenden einen vertieften Einblick sowohl in den Ablauf von Forschung als auch eine Bearbeitung einer eigenen experimentellen Forschungsaufgabe ermöglichen soll. Anlass waren die Berücksichtigung eines „Wissens über Erkenntnisgewinnung in der Disziplin“ im Modell des „Erweiterten Fachwissens für den schulischen Kontext“ (PSI) sowie Erkenntnisse empirischer Studien, die die Relevanz eigener Forschungserfahrung für das Unterrichten naturwissenschaftlicher Erkenntnisgewinnungsprozesse zeigen. Hier stellen wir eine neue Lehrveranstaltung (4 SWS) vor, die den angehenden Lehrkräften Forschungserfahrung ermöglicht (Seminar und Praktikum). Die Lehrveranstaltung vermittelt Einblicke in Forschung und die „Natur der Naturwissenschaften“, ermöglicht das Durchführen eigener wissenschaftlicher und schulrelevanter Experimente und bietet eine angemessene Reflexion über die verschiedenen Kurselemente. Die Evaluationsergebnisse sind überwiegend positiv, zeigen aber auch, dass für die Studierenden die wahrgenommene Schulrelevanz und die fachdidaktischen Aspekte ein wichtiges Kriterium für die positive Bewertung sind.
Algorithmen als Dozierende?
(2023)
Auf maschinellem Lernen basierende Tools haben schon längst Einzug in unseren Alltag gefunden und so konnten auch in der Lehrkräftebildung erste Anwendungen entwickelt, erprobt und evaluiert werden. Im Teilprojekt Physikdidaktik des Schwerpunktes 2 „Schulpraktische Studien“ wurden auf Basis eines Rahmenmodells für Reflexion (Nowak et al., 2019) automatisierte Analysemethoden (Wulff et al., 2020) entwickelt und fanden Einzug in universitäre fachdidaktische Lehre (Mientus et al., 2021a). Mit dem Projekt konnten Potenziale KI-basierter Unterstützung aufgezeigt und verstetigt sowie spezifische Herausforderungen identifiziert werden. Dieser Beitrag skizziert ausgewählte Anwendungsmöglichkeiten und weiterführende Forschungen unter dem Gesichtspunkt der Akzeptanz computerunterstützter Lehre.
Reflexion ist eine Schlüsselkategorie für die professionelle Entwicklung von Lehrkräften, welche als Ausbildungsziel in den Bildungsstandards für die Lehrkräftebildung verankert ist. Eine Verstetigung universitär geprägter Forschung und Modellierung in der praxisnahen Anwendung im schulischen Kontext bietet Potentiale nachhaltiger Professionalisierung. Die Stärkung reflexionsbezogener Kompetenzen durch Empirie und Anwendung scheint eine phasenübergreifende Herausforderung der Lehrkräftebildung zu sein, die es zu bewältigen gilt. Ziele des Tagungsbandes Reflexion in der Lehrkräftebildung sind eine theoretische Schärfung des Konzeptes „Reflexive Professionalisierung“ und der Austausch über Fragen der Einbettung wirksamer reflexionsbezogener Lerngelegenheiten in die Lehrkräftebildung. Forschende und Lehrende der‚ drei Phasen (Studium, Referendariat sowie Fort- und Weiterbildung) der Lehrkräftebildung stellen Lehrkonzepte und Forschungsprojekte zum Thema Reflexion in der Lehrkräftebildung vor und diskutieren diese. Gemeinsam mit Teilnehmenden aller Phasen und von verschiedenen Standorten der Lehrkräftebildung werden zukünftige Herausforderungen identifiziert und Lösungsansätze herausgearbeitet.
Für die Entwicklung professioneller Handlungskompetenzen angehender Lehrkräfte stellt die Unterrichtsreflexion ein wichtiges Instrument dar, um Theoriewissen und Praxiserfahrungen in Beziehung zu setzen. Die Auswertung von Unterrichtsreflexionen und eine entsprechende Rückmeldung stellt Forschende und Dozierende allerdings vor praktische wie theoretische Herausforderungen. Im Kontext der Forschung zu Künstlicher Intelligenz (KI) entwickelte Methoden bieten hier neue Potenziale. Der Beitrag stellt überblicksartig zwei Teilstudien vor, die mit Hilfe von KI-Methoden wie dem maschinellen Lernen untersuchen, inwieweit eine Auswertung von Unterrichtsreflexionen angehender Physiklehrkräfte auf Basis eines theoretisch abgeleiteten Reflexionsmodells und die automatisierte Rückmeldung hierzu möglich sind. Dabei wurden unterschiedliche Ansätze des maschinellen Lernens verwendet, um modellbasierte Klassifikation und Exploration von Themen in Unterrichtsreflexionen umzusetzen. Die Genauigkeit der Ergebnisse wurde vor allem durch sog. Große Sprachmodelle gesteigert, die auch den Transfer auf andere Standorte und Fächer ermöglichen. Für die fachdidaktische Forschung bedeuten sie jedoch wiederum neue Herausforderungen, wie etwa systematische Verzerrungen und Intransparenz von Entscheidungen. Dennoch empfehlen wir, die Potenziale der KI-basierten Methoden gründlicher zu erforschen und konsequent in der Praxis (etwa in Form von Webanwendungen) zu implementieren.
Lehramtsstudierende äußern vielfach den Wunsch nach umfangreichen praktischen Lerngelegenheiten. Insbesondere fallbasierte Lehr-Lern-Konzepte scheinen diesen Ansprüchen gerecht zu werden. Dieser Beitrag stellt ein an der Universität Potsdam entwickeltes Seminarkonzept vor, welches diesen Transfer zu fördern versucht. Die Basis des Konzepts bildet der Einsatz erfahrungsbasiert entwickelter Textvignetten pädagogischer Situationen. Im Rahmen der Begleitseminare zum Praktikum in pädagogisch-psychologischen Handlungsfeldern (PppH) wurde die kollegiale Fallbesprechung als eine Form zur angestrebten Transferförderung in dieses Seminarkonzept integriert. Dieser Beitrag skizziert zunächst die erfahrungsbasierte Entwicklung der Vignetten sowie die theoretischen Grundlagen des Seminarkonzepts. Im Anschluss werden die praktische Implementation und erfahrungsbasierte konzeptionelle Änderung (design-based-research) in der Lehre beschrieben sowie erste Ergebnisse der systematischen empirischen Erprobung im Rahmen des PppH vorgestellt. Abschließend diskutieren die Autoren die Herausforderungen der praktischen Umsetzung auch mit Blick auf das Verstetigungsvorhaben.
Late-type stars are by far the most frequent stars in the universe and of fundamental interest to various fields of astronomy – most notably to Galactic archaeology and exoplanet research. However, such stars barely change during their main sequence lifetime; their temperature, luminosity, or chemical composition evolve only very slowly over the course of billions of years. As such, it is difficult to obtain the age of such a star, especially when it is isolated and no other indications (like cluster association) can be used. Gyrochronology offers a way to overcome this problem.
Stars, just like all other objects in the universe, rotate and the rate at which stars rotate impacts many aspects of their appearance and evolution. Gyrochronology leverages the observed rotation rate of a late-type main sequence star and its systematic evolution to estimate their ages. Unlike the above-mentioned parameters, the rotation rate of a main sequence star changes drastically throughout its main sequence lifetime; stars spin down. The youngest stars rotate every few hours, whereas much older stars rotate only about once a month, or – in the case of some late M-stars – once in a hundred days. Given that this spindown is systematic (with an additional mass dependence), it gave rise to the idea of using the observed rotation rate of a star (and its mass or a suitable proxy thereof) to estimate a star’s age. This has been explored widely in young stellar open clusters but remains essentially unconstrained for stars older than the sun, and K and M stars older than 1 Gyr.
This thesis focuses on the continued exploration of the spindown behavior to assess, whether gyrochronology remains applicable for stars of old ages, whether it is universal for late-type main sequence stars (including field stars), and to provide calibration mileposts for spindown models. To accomplish this, I have analyzed data from Kepler space telescope for the open clusters Ruprecht 147 (2.7 Gyr old) and M 67 (4 Gyr). Time series photometry data (light curves)
were obtained for both clusters during Kepler’s K2 mission. However, due to technical limitations and telescope malfunctions, extracting usable data from the K2 mission to identify (especially long) rotation periods requires extensive data preparation.
For Ruprecht 147, I have compiled a list of about 300 cluster members from the literature and adopted preprocessed light curves from the Kepler archive where available. They have been cleaned of the gravest of data artifacts but still contained systematics. After correcting them for said artifacts, I was able to identify rotation periods in 31 of them.
For M 67 more effort was taken. My work on Ruprecht 147 has shown the limitations imposed by the preselection of Kepler targets. Therefore, I adopted the time series full frame image directly and performed photometry on a much higher spatial resolution to be able to obtain data for as many stars as possible. This also means that I had to deal with the ubiquitous artifacts in Kepler data. For that, I devised a method that correlates the artificial flux variations with the ongoing drift of the telescope pointing in order to remove it. This process was a large success and I was able to create light curves whose quality match and even exceede those that were created by the Kepler mission – all while operating on higher spatial resolution and processing fainter stars. Ultimately, I was able to identify signs of periodic variability in the (created) light curves for 31 and 47 stars in Ruprecht 147 and M 67, respectively. My data connect well to bluer stars of cluster of the same age and extend for the first time to stars redder than early-K and older than 1 Gyr. The cluster data show a clear flattening in the distribution of Ruprecht 147 and even a downturn for M 67, resulting in a somewhat sinusoidal shape. With that, I have shown that the systematic spindown of stars continues at least until 4 Gyr and stars continue to live on a single surface in age-rotation periods-mass space which allows gyrochronology to be used at least up to that age. However, the shape of the spindown – as exemplified by the newly discovered sinusoidal shape of the cluster sequence – deviates strongly from the expectations.
I then compiled an extensive sample of rotation data in open clusters – very much including my own work – and used the resulting cluster skeleton (with each cluster forming a rip in color-rotation period-mass space) to investigate if field stars follow the same spindown as cluster stars. For the field stars, I used wide binaries, which – with their shared origin and coevality – are in a sense the smallest possible open clusters. I devised an empirical method to evaluate the consistency between the rotation rates of the wide binary components and found that the vast majority of them are in fact consistent with what is observed in open clusters. This leads me to conclude that gyrochronology – calibrated on open clusters – can be applied to determine the ages of field stars.
Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.
Reactive eutectic media based on ammonium formate for the valorization of bio-sourced materials
(2023)
In the last several decades eutectic mixtures of different compositions were successfully used as solvents for vast amount of chemical processes, and only relatively recently they were discovered to be widely spread in nature. As such they are discussed as a third liquid media of the living cell, that is composed of common cell metabolites. Such media may also incorporate water as a eutectic component in order to regulate properties such as enzyme activity or viscosity. Taking inspiration form such sophisticated use of eutectic mixtures, this thesis will explore the use of reactive eutectic media (REM) for organic synthesis. Such unconventional media are characterized by the reactivity of their components, which means that mixture may assume the role of the solvent as well as the reactant itself.
The thesis focuses on novel REM based on ammonium formate and investigates their potential for the valorization of bio-sourced materials. The use of REM allows the performance of a number of solvent-free reactions, which entails the benefits of a superior atom and energy economy, higher yields and faster rates compared to reactions in solution. This is evident for the Maillard reaction between ammonium formate and various monosaccharides for the synthesis of substituted pyrazines as well as for a Leuckart type reaction between ammonium formate and levulinic acid for the synthesis of 5-methyl-2-pyrrolidone. Furthermore, reaction of ammonium formate with citric acid for the synthesis of yet undiscovered fluorophores, shows that synthesis in REM can open up unexpected reaction pathways.
Another focus of the thesis is the study of water as a third component in the REM. As a result, the concept of two different dilution regimes (tertiary REM and in REM in solvent) appears useful for understanding the influence of water. It is shown that small amounts of water can be of great benefit for the reaction, by reducing viscosity and at the same time increasing reaction yields.
REM based on ammonium formate and organic acids are employed for lignocellulosic biomass treatment. The thesis thereby introduces an alternative approach towards lignocellulosic biomass fractionation that promises a considerable process intensification by the simultaneous generation of cellulose and lignin as well as the production of value-added chemicals from REM components. The thesis investigates the generated cellulose and the pathway to nanocellulose generation and also includes the structural analysis of extracted lignin.
Finally, the thesis investigates the potential of microwave heating to run chemical reactions in REM and describes the synergy between these two approaches. Microwave heating for chemical reactions and the use of eutectic mixtures as alternative reaction media are two research fields that are often described in the scope of green chemistry. The thesis will therefore also contain a closer inspection of this terminology and its greater goal of sustainability.
The Lyman-𝛼 (Ly𝛼) line commonly assists in the detection of high-redshift galaxies, the so-called Lyman-alpha emitters (LAEs). LAEs are useful tools to study the baryonic matter distribution of the high-redshift universe. Exploring their spatial distribution not only reveals the large-scale structure of the universe at early epochs, but it also provides an insight into the early formation and evolution of the galaxies we observe today. Because dark matter halos (DMHs) serve as sites of galaxy formation, the LAE distribution also traces that of the underlying dark matter. However, the details of this relation and their co-evolution over time remain unclear. Moreover, theoretical studies predict that the spatial distribution of LAEs also impacts their own circumgalactic medium (CGM) by influencing their extended Ly𝛼 gaseous halos (LAHs), whose origin is still under investigation. In this thesis, I make several contributions to improve the knowledge on these fields using samples of LAEs observed with the Multi Unit Spectroscopic Explorer (MUSE) at redshifts of 3 < 𝑧 < 6.
Das 16. Herbsttreffen Patholinguistik mit dem Schwerpunktthema »Schnittstelle Alltag: Transfer und Teilhabe in der Sprachtherapie« fand am 19.11.2022 als Online-Veranstaltung statt. Das Herbsttreffen wird seit 2007 jährlich vom Verband für Patholinguistik e.V. (vpl), seit 2021 vom Deutschen Bundesverband für akademische Sprachtherapie und Logopädie (dbs) in Kooperation mit der Universität Potsdam durchgeführt. Der vorliegende Tagungsband beinhaltet die Vorträge zum Schwerpunktthema sowie die Posterpräsentationen zu weiteren Themen aus der sprachtherapeutischen Forschung und Praxis.
High growth firms (HGFs) are important for job creation and considered to be precursors of economic growth. We investigate how formal institutions, like product- and labor-market regulations, as well as the quality of regional governments that implement these regulations, affect HGF development across European regions. Using data from Eurostat, OECD, WEF, and Gothenburg University, we show that both regulatory stringency and the quality of the regional government influence the regional shares of HGFs. More importantly, we find that the effect of labor- and product-market regulations ultimately depends on the quality of regional governments: in regions with high quality of government, the share of HGFs is neither affected by the level of product market regulation, nor by more or less flexibility in hiring and firing practices. Our findings contribute to the debate on the effects of regulations by showing that regulations are not, per se, “good, bad, and ugly”, rather their impact depends on the efficiency of regional governments. Our paper offers important building blocks to develop tailored policy measures that may influence the development of HGFs in a region.
Solar photocatalysis is the one of leading concepts of research in the current paradigm of sustainable chemical industry. For actual practical implementation of sunlight-driven catalytic processes in organic synthesis, a cheap, efficient, versatile and robust heterogeneous catalyst is necessary. Carbon nitrides are a class of organic semiconductors who are known to fulfill these requirements.
First, current state of solar photocatalysis in economy, industry and lab research is overviewed, outlining EU project funding, prospective synthetic and reforming bulk processes, small scale solar organic chemistry, and existing reactor designs and prototypes, concluding feasibility of the approach.
Then, the photocatalytic aerobic cleavage of oximes to corresponding aldehydes and ketones by anionic poly(heptazine imide) carbon nitride is discussed. The reaction provides a feasible method of deprotection and formation of carbonyl compounds from nitrosation products and serves as a convenient model to study chromoselectivity and photophysics of energy transfer in heterogeneous photocatalysis.
Afterwards, the ability of mesoporous graphitic carbon nitride to conduct proton-coupled electron transfer was utilized for the direct oxygenation of 1,3-oxazolidin-2-ones to corresponding 1,3-oxazlidine-2,4-diones. This reaction provides an easier access to a key scaffold of diverse types of drugs and agrochemicals.
Finally, a series of novel carbon nitrides based on poly(triazine imide) and poly(heptazine imide) structure was synthesized from cyanamide and potassium rhodizonate. These catalysts demonstrated a good performance in a set of photocatalytic benchmark reactions, including aerobic oxidation, dual nickel photoredox catalysis, hydrogen peroxide evolution and chromoselective transformation of organosulfur precursors.
Concluding, the scope of carbon nitride utilization for net-oxidative and net-neutral photocatalytic processes was expanded, and a new tunable platform for catalyst synthesis was discovered.
Aus dem Inhalt:
- Dimensionen von Macht – Unter Betrachtung des ethischen Berufskodex, der professionellen Haltung und systemimmanenten Dilemmata im ungarischen Kinderschutzsystem
– Das 12. Zusatzprotokoll zur EMRK – Chancen und Potenziale eines allgemeinen und umfassenden Diskriminierungsverbots
- Zum aktuellen Stand und zu aktuellen Fragen des Menschenrechtsschutzes von LGBTQI+-Personen
- Fragen nach gerechter Verteilung – eine menschenrechtliche Analyse der Allokation am Beispiel von COVID-19-Impfstoffen für Ältere
- Extraterritorial Constitutional Rights: A Comparative Case Study of the United States and Germany*
- Bericht über die Tätigkeit des Menschenrechtsausschusses der Vereinten Nationen im Jahre 2022 – Teil II: Individualbeschwerden
Vorwort
(2023)
Die Königlich Preußische Seehandlung, nach der heute die „Stiftung Preußische Seehandlung“ benannt ist, besitzt eine lange und vielseitige Geschichte. Der anlässlich des Stiftungsjubiläums erscheinende Band wirft einen Blick auf die Gründungskonstellation 1772, als König Friedrich II. die Gewerbe in Preußen fördern wollte. Er zeichnet die Aktivitäten von Männern an der Spitze der Seehandlung nach, wie Finanzminister Carl August von Struensee und dem unter- nehmerisch denkenden Karrierebeamten Christian Rother.
Das Gebäude der Seehandlung wurde nach 1900 neu erbaut und ist heute in der Berlin-Brandenburgischen Akademie am Gendarmenmarkt lebendige Gegenwart. Die Seehand- lung erhielt von ihren Zeitgenossen im 19. Jahr- hundert ambivalente Urteile. Ein Ausblick auf die Geschichte der Stiftung Preußische Seehandlung seit 1983 zeigt das Bemühen um Kunst- und Kul- turförderung als zentrale Aufgabe.
Im 19. Jahrhundert waren Konversationslexika, wie der Name schon andeutet, dazu gedacht, die Konversation in Salon und Vereinen mit Informationen zu bereichern. In den einzelnen Artikeln wurde auf Präzision, Genauigkeit und Überprüfbarkeit gesetzt, um der Leserschaft auch ein eigenes Urteil zu ermöglichen. Die „Seehandlungs-Societät in Preußen“ oder „Seehandlung, preußische“, wie sie in deutschen Lexika vorkommt, wandelte sich im 19. Jahrhundert zur Staatsbank. In der ersten Hälfte des 19. Jahrhunderts fielen die Urteile der Lexika meist ablehnend aus: Die Seehandlung erschien als eine wirtschaftspolitisch katastrophale Fehlentwicklung. Eine besondere Rolle spielte der Präsident Christian (von) Rother, der die Seehandlung zum selbständigen Unternehmen gemacht hatte. Der Wandel der allgemeinen Lexika in der zweiten Hälfte des 19. Jahrhunderts veränderte auch die Sicht auf die Seehandlung. Die Geschäfte der Bank wurden positiv hervorgehoben, die Beurteilungen verwiesen auf Statistiken und Bilanzen. Der Fokus rückte von den leitenden Personen der Seehandlung hin zum Kampf um Handelsmonopole und den preußischen Landtag als öffentlichem Forum. Das vernichtende Urteil der ersten Hälfte des 19. Jahrhunderts war einer differenzierten Bewertung der Bankentätigkeit gewichen.
Kein anderer Akteur prägte die ersten Dezennien der Preußischen Seehandlung so sehr wie Carl August von Struensee. Als deren Direktor und dann als preußischer Finanzminister initiierte er zwischen 1782 und seinem Tod im Jahr 1804 bereits maßgeblich den langen Transformationsprozess der Seehandlung vom königlichen Wachs- und Salzmonopol hin zu einer Staatsbank, der erst im 20. Jahrhundert zum Abschluss kommen sollte. In dem Beitrag wird Struensee sowohl als Wirtschaftstheoretiker in den ökonomischen Diskursen der Aufklärung zwischen Physiokratie und Frühliberalismus situiert als auch als ein Finanzpolitiker mit konsequent europäischem Handlungshorizont vor dem Hintergrund einer beschleunigten globalen und kolonialen Mächtekonkurrenz porträtiert.
Die Königlich Preußische Seehandlung, nach der heute die „Stiftung Preußische Seehandlung“ benannt ist, besitzt eine lange und vielseitige Geschichte. Der anlässlich des Stiftungsjubiläums erscheinende Band wirft einen Blick auf die Gründungskonstellation 1772, als König Friedrich II. die Gewerbe in Preußen fördern wollte. Er zeichnet die Aktivitäten von Männern an der Spitze der Seehandlung nach, wie Finanzminister Carl August von Struensee und dem unternehmerisch denkenden Karrierebeamten Christian Rother. Das Gebäude der Seehandlung wurde nach 1900 neu erbaut und ist heute in der Berlin-Brandenburgischen Akademie am Gendarmenmarkt lebendige Gegenwart. Die Seehandlung erhielt von ihren Zeitgenossen im 19. Jahrhundert ambivalente Urteile. Ein Ausblick auf die Geschichte der Stiftung Preußische Seehandlung seit 1983 zeigt das Bemühen um Kunst- und Kulturförderung als zentrale Aufgabe.
The Andean Cordillera is a mountain range located at the western South American margin and is part of the Eastern- Circum-Pacific orogenic Belt. The ~7000 km long mountain range is one of the longest on Earth and hosts the second largest orogenic plateau in the world, the Altiplano-Puna plateau. The Andes are known as a non-collisional subduction-type orogen which developed as a result of the interaction between the subducted oceanic Nazca plate and the South American continental plate. The different Andean segments exhibit along-strike variations of morphotectonic provinces characterized by different elevations, volcanic activity, deformation styles, crustal thickness, shortening magnitude and oceanic plate geometry. Most of the present-day elevation can be explained by crustal shortening in the last ~50 Ma, with the shortening magnitude decreasing from ~300 km in the central (15°S-30°S) segment to less than half that in the southern part (30°S-40°S). Several factors were proposed that might control the magnitude and acceleration of shortening of the Central Andes in the last 15 Ma. One important factor is likely the slab geometry. At 27-33°S, the slab dips horizontally at ~100 km depth due to the subduction of the buoyant Juan Fernandez Ridge, forming the Pampean flat-slab. This horizontal subduction is thought to influence the thermo-mechanical state of the Sierras Pampeanas foreland, for instance, by strengthening the lithosphere and promoting the thick-skinned propagation of deformation to the east, resulting in the uplift of the Sierras Pampeanas basement blocks. The flat-slab has migrated southwards from the Altiplano latitude at ~30 Ma to its present-day position and the processes and consequences associated to its passage on the contemporaneous acceleration of the shortening rate in Central Andes remain unclear. Although the passage of the flat-slab could offer an explanation to the acceleration of the shortening, the timing does not explain the two pulses of shortening at about 15 Ma and 4 Ma that are suggested from geological observations. I hypothesize that deformation in the Central Andes is controlled by a complex interaction between the subduction dynamics of the Nazca plate and the dynamic strengthening and weakening of the South American plate due to several upper plate processes. To test this hypothesis, a detailed investigation into the role of the flat-slab, the structural inheritance of the continental plate, and the subduction dynamics in the Andes is needed. Therefore, I have built two classes of numerical thermo-mechanical models: (i) The first class of models are a series of generic E-W-oriented high-resolution 2D subduction models thatinclude flat subduction in order to investigate the role of the subduction dynamics on the temporal variability of the shortening rate in the Central Andes at Altiplano latitudes (~21°S). The shortening rate from the models was then validated with the observed tectonic shortening rate in the Central Andes. (ii) The second class of models are a series of 3D data-driven models of the present-day Pampean flat-slab configuration and the Sierras Pampeanas (26-42°S). The models aim to investigate the relative contribution of the present-day flat subduction and inherited structures in the continental lithosphere on the strain localization. Both model classes were built using the advanced finite element geodynamic code ASPECT.
The first main finding of this work is to suggest that the temporal variability of shortening in the Central Andes is primarily controlled by the subduction dynamics of the Nazca plate while it penetrates into the mantle transition zone. These dynamics depends on the westward velocity of the South American plate that provides the main crustal shortening force to the Andes and forces the trench to retreat. When the subducting plate reaches the lower mantle, it buckles on it-self until the forced trench retreat causes the slab to steepen in the upper mantle in contrast with the classical slab-anchoring model. The steepening of the slab hinders the trench causing it to resist the advancing South American plate, resulting in the pulsatile shortening. This buckling and steepening subduction regime could have been initiated because of the overall decrease in the westwards velocity of the South American plate. In addition, the passage of the flat-slab is required to promote the shortening of the continental plate because flat subduction scrapes the mantle lithosphere, thus weakening the continental plate. This process contributes to the efficient shortening when the trench is hindered, followed by mantle lithosphere delamination at ~20 Ma. Finally, the underthrusting of the Brazilian cratonic shield beneath the orogen occurs at ~11 Ma due to the mechanical weakening of the thick sediments covered the shield margin, and due to the decreasing resistance of the weakened lithosphere of the orogen.
The second main finding of this work is to suggest that the cold flat-slab strengthens the overriding continental lithosphere and prevents strain localization. Therefore, the deformation is transmitted to the eastern front of the flat-slab segment by the shear stress operating at the subduction interface, thus the flat-slab acts like an indenter that “bulldozes” the mantle-keel of the continental lithosphere. The offset in the propagation of deformation to the east between the flat and steeper slab segments in the south causes the formation of a transpressive dextral shear zone. Here, inherited faults of past tectonic events are reactivated and further localize the deformation in an en-echelon strike-slip shear zone, through a mechanism that I refer to as “flat-slab conveyor”. Specifically, the shallowing of the flat-slab causes the lateral deformation, which explains the timing of multiple geological events preceding the arrival of the flat-slab at 33°S. These include the onset of the compression and of the transition between thin to thick-skinned deformation styles resulting from the crustal contraction of the crust in the Sierras Pampeanas some 10 and 6 Myr before the Juan Fernandez Ridge collision at that latitude, respectively.
No evidence of growth impairment after forced migration in Polish school children after World War II
(2023)
Background: Migration is omnipresent. It can come hand in hand with emotional stress which is known to influence the growth of children.
Objective: The aim of this study was to analyse whether type of migration (forced or voluntary) and the geographic direction had influenced the growth of Polish children after World War II.
Sample and Methods: A sub dataset of 2,208 individuals between the ages of 2-20, created from data of the 2nd Polish Anthropological Survey carried out in 1966–1969, including anthropometrical data and social and demographic information based on questionnaire, was used to analyse migration effects.
Results: No association could be found between the direction of migration and the height of the children. The confidence intervals of the means of all classified migration categories overlap significantly and the effect size of the influence of migration category on height is ds=.140, which is too low to see any effects, even if there were one.
Conclusion: Neither forced nor voluntary migration in Poland after World War II led to a change in height in children of migrating families.
Background: Assessing short-term growth in humans is still fraught with difficulties. Especially when looking for small variations and increments, such as mini growth spurts, high precision instruments or frequent measurements are necessary. Daily measurements however require a lot of effort, both for anthropologists and for the subjects. Therefore, new sophisticated approaches are needed that reduce fluctuations and reveal underlying patterns.
Objectives: Changepoints are abrupt variations in the properties of time series data. In the context of growth, such variations could be variation in mean height. By adjusting the variance and using different growth models, we assessed the ability of changepoint analysis to analyse short-term growth and detect mini growth spurts.
Sample and Methods: We performed Bayesian changepoint analysis on simulated growth data using the bcp package in R. Simulated growth patterns included stasis, linear growth, catch-up growth, and mini growth spurts. Specificity and a normalised variant of the Matthews correlation coefficient (MCC) were used to assess the algorithm’s performance. Welch’s t-test was used to compare differences of the mean.
Results: First results show that changepoint analysis can detect mini growth spurts. However, the ability to detect mini growth spurts is highly dependent on measurement error. Data preparation, such as ranking and rotating time series data, showed negligible improvements. Missing data was an issue and may affect the prediction quality of the classification metrics.
Conclusion: Changepoint analysis is a promising tool to analyse short-term growth. However, further optimisation and analysis of real growth data is needed to make broader generalisations.
Human growth data analysis and statistics – the 5th Gülpe International Student Summer School
(2023)
The Summer School in Gülpe (Ecological Station of the University of Potsdam) offers an exceptional learning opportunity for students to apply their knowledge and skills to real-world problems. With the guidance of experienced human biologists, statisticians, and programmers, students have the unique chance to analyze their own data and gain valuable insights. This interdisciplinary setting not only bridges different research areas but also leads to highly valuable outputs. The progress of students within just a few days is truly remarkable, especially when they are motivated and receive immediate feedback on their questions, problems, and results. The Summer School covers a wide range of topics, with this year’s focus mainly on two areas: understanding the impact of socioeconomic and physiological factors on human development and mastering statistical techniques for analyzing data such as changepoint analysis and the St. Nicolas House Analysis (SNHA) to visualize interacting variables. The latter technique, born out of the Summer School’s emphasis on gaining comprehensive data insights and understanding major relationships, has proven to be a valuable tool for researchers in the field. The articles in this special issue demonstrate that the Summer School in Gülpe stands as a testament to the power of practical learning and collaboration. Students who attend not only gain hands-on experience but also benefit from the expertise of professionals and the opportunity to engage with peers from diverse disciplines.
Twenty-four scientists met for the annual Auxological conference held at Krobielowice castle, Poland, to discuss the diverse influences of the environment and of social behavior on growth following last year’s focus on growth and public health concerns (Hermanussen et al., 2022b). Growth and final body size exhibit marked plastic responses to ecological conditions. Among the shortest are the pygmoid people of Rampasasa, Flores, Indonesia, who still live under most secluded insular conditions. Genetics and nutrition are usually considered responsible for the poor growth in many parts of this world, but evidence is accumulating on the prominent impact of social embedding on child growth. Secular trends not only in the growth of height, but also in body proportions, accompany the secular changes in the social, economic and political conditions, with major influences on the emotional and educational circumstances under which the children grow up (Bogin, 2021). Aspects of developmental tempo and aspects of sports were discussed, and the impact of migration by the example of women from Bangladesh who grew up in the UK. Child growth was considered in particular from the point of view of strategic adjustments of individual size within the network of its social group. Theoretical considerations on network characteristics were presented and related to the evolutionary conservation of growth regulating hypothalamic neuropeptides that have been shown to link behavior and physical growth in the vertebrate species. New statistical approaches were presented for the evaluation of short term growth measurements that permit monitoring child growth at intervals of a few days and weeks.
The knowledge of transformation pathways and identification of transformation products (TPs) of veterinary drugs is important for animal health, food, and environmental matters. The active agent Monensin (MON) belongs to the ionophore antibiotics and is widely used as a veterinary drug against coccidiosis in broiler farming. However, no electrochemically (EC) generated TPs of MON have been described so far. In this study, the online coupling of EC and mass spectrometry (MS) was used for the generation of oxidative TPs. EC-conditions were optimized with respect to working electrode material, solvent, modifier, and potential polarity. Subsequent LC/HRMS (liquid+ chromatography/high resolution mass spectrometry) and MS/MS experiments were performed to identify the structures of derived TPs by a suspected target analysis. The obtained EC-results were compared to TPs observed in metabolism tests with microsomes and hydrolysis experiments of MON. Five previously undescribed TPs of MON were identified in our EC/MS based study and one TP, which was already known from literature and found by a microsomal assay, could be confirmed. Two and three further TPs were found as products in microsomal tests and following hydrolysis, respectively. We found decarboxylation, O-demethylation and acid-catalyzed ring-opening reactions to be the major mechanisms of MON transformation
Dermal Delivery of the High-Molecular-Weight Drug Tacrolimus by Means of Polyglycerol-Based Nanogels
(2019)
Polyglycerol-based thermoresponsive nanogels (tNGs) have been shown to have excellent skin hydration properties and to be valuable delivery systems for sustained release of drugs into skin. In this study, we compared the skin penetration of tacrolimus formulated in tNGs with a commercial 0.1% tacrolimus ointment. The penetration of the drug was investigated in ex vivo abdominal and breast skin, while different methods for skin barrier disruption were investigated to improve skin permeability or simulate inflammatory conditions with compromised skin barrier. The amount of penetrated tacrolimus was measured in skin extracts by liquid chromatography tandem-mass spectrometry (LC-MS/MS), whereas the inflammatory markers IL-6 and IL-8 were detected by enzyme-linked immunosorbent assay (ELISA). Higher amounts of tacrolimus penetrated in breast as compared to abdominal skin or in barrier-disrupted as compared to intact skin, confirming that the stratum corneum is the main barrier for tacrolimus skin penetration. The anti-proliferative effect of the penetrated drug was measured in skin tissue/Jurkat cells co-cultures. Interestingly, tNGs exhibited similar anti-proliferative effects as the 0.1% tacrolimus ointment. We conclude that polyglycerol-based nanogels represent an interesting alternative to paraffin-based formulations for the treatment of inflammatory skin conditions.
In this paper, we investigate the continuous version of modified iterative Runge–Kutta-type methods for nonlinear inverse ill-posed problems proposed in a previous work. The convergence analysis is proved under the tangential cone condition, a modified discrepancy principle, i.e., the stopping time T is a solution of ∥𝐹(𝑥𝛿(𝑇))−𝑦𝛿∥=𝜏𝛿+ for some 𝛿+>𝛿, and an appropriate source condition. We yield the optimal rate of convergence.
In this study, we analyze interactions in lake and lake catchment systems of a continuous permafrost area. We assessed colored dissolved organic matter (CDOM) absorption at 440 nm (a(440)(CDOM)) and absorption slope (S300-500) in lakes using field sampling and optical remote sensing data for an area of 350 km(2) in Central Yamal, Siberia. Applying a CDOM algorithm (ratio of green and red band reflectance) for two high spatial resolution multispectral GeoEye-1 and Worldview-2 satellite images, we were able to extrapolate the a()(CDOM) data from 18 lakes sampled in the field to 356 lakes in the study area (model R-2 = 0.79). Values of a(440)(CDOM) in 356 lakes varied from 0.48 to 8.35 m(-1) with a median of 1.43 m(-1). This a()(CDOM) dataset was used to relate lake CDOM to 17 lake and lake catchment parameters derived from optical and radar remote sensing data and from digital elevation model analysis in order to establish the parameters controlling CDOM in lakes on the Yamal Peninsula. Regression tree model and boosted regression tree analysis showed that the activity of cryogenic processes (thermocirques) in the lake shores and lake water level were the two most important controls, explaining 48.4% and 28.4% of lake CDOM, respectively (R-2 = 0.61). Activation of thermocirques led to a large input of terrestrial organic matter and sediments from catchments and thawed permafrost to lakes (n = 15, mean a(440)(CDOM) = 5.3 m(-1)). Large lakes on the floodplain with a connection to Mordy-Yakha River received more CDOM (n = 7, mean a(440)(CDOM) = 3.8 m(-1)) compared to lakes located on higher terraces.
The light reactions of photosynthesis are carried out by a series of multiprotein complexes embedded in thylakoid membranes. Among them, photosystem I (PSI), acting as plastocyanin-ferderoxin oxidoreductase, catalyzes the final reaction. Together with light-harvesting antenna I, PSI forms a high-molecular-weight supercomplex of ~600 kDa, consisting of eighteen subunits and nearly two hundred co-factors. Assembly of the various components into a functional thylakoid membrane complex requires precise coordination, which is provided by the assembly machinery. Although this includes a small number of proteins (PSI assembly factors) that have been shown to play a role in the formation of PSI, the process as a whole, as well as the intricacy of its members, remains largely unexplored.
In the present work, two approaches were used to find candidate PSI assembly factors. First, EnsembleNet was used to select proteins thought to be functionally related to known PSI assembly factors in Arabidopsis thaliana (approach I), and second, co-immunoprecipitation (Co-IP) of tagged PSI assembly factors in Nicotiana tabacum was performed (approach II).
Here, the novel PSI assembly factors designated CO-EXPRESSED WITH PSI ASSEMBLY 1 (CEPA1) and Ycf4-INTERACTING PROTEIN 1 (Y4IP1) were identified. A. thaliana null mutants for CEPA1 and Y4IP1 showed a growth phenotype and pale leaves compared with the wild type. Biophysical experiments using pulse amplitude modulation (PAM) revealed insufficient electron transport on the PSII acceptor side. Biochemical analyses revealed that both CEPA1 and Y4IP1 are specifically involved in PSI accumulation in A. thaliana at the post-translational level but are not essential. Consistent with their roles as factors in the assembly of a thylakoid membrane protein complex, the two proteins localize to thylakoid membranes. Remarkably, cepa1 y4ip1 double mutants exhibited lethal phenotypes in early developmental stages under photoautotrophic growth. Finally, co-IP and native gel experiments supported a possible role for CEPA1 and Y4IP1 in mediating PSI assembly in conjunction with other PSI assembly factors (e.g., PPD1- and PSA3-CEPA1 and Ycf4-Y4IP1). The fact that CEPA1 and Y4IP1 are found exclusively in green algae and higher plants suggests eukaryote-specific functions. Although the specific mechanisms need further investigation, CEPA1 and Y4IP1 are two novel assembly factors that contribute to PSI formation.
We investigate whether political ideology has an observable effect on decarbonization ambition, renewable power aims, and preferences for power system balancing technologies in four European countries. Based on the Energy Logics framework, we identify ideologically different transition strategies (state-centered, market-centered, grassroots-centered) contained in government policies and opposition party programs valid in 2019. We compare these policies and programs with citizen poll data. We find that ideology has a small effect: governments and political parties across the spectrum have similar, and relatively ambitious, decarbonization and renewables targets. This mirrors citizens' strong support for ambitious action regardless of their ideological self-description. However, whereas political positions on phasing out fossil fuel power are clear across the policy space, positions on phasing in new flexibility options to balance intermittent renewables are vague or non-existent. As parties and citizens agree on strong climate and renewable power aims, the policy ambition is likely to remain high, even if governments change.
Prediction of hybrid biomass in Arabidopsis thaliana by selected parental SNP and metabolic markers
(2009)
A recombinant inbred line (RIL) population, derived from two Arabidopsis thaliana accessions, and the corresponding testcrosses with these two original accessions were used for the development and validation of machine learning models to predict the biomass of hybrids. Genetic and metabolic information of the RILs served as predictors. Feature selection reduced the number of variables (genetic and metabolic markers) in the models by more than 80% without impairing the predictive power. Thus, potential biomarkers have been revealed. Metabolites were shown to bear information on inherited macroscopic phenotypes. This proof of concept could be interesting for breeders. The example population exhibits substantial mid-parent biomass heterosis. The results of feature selection could therefore be used to shed light on the origin of heterosis. In this respect, mainly dominance effects were detected.
Prediction of hybrid biomass in Arabidopsis thaliana by selected parental SNP and metabolic markers
(2009)
A recombinant inbred line (RIL) population, derived from two Arabidopsis thaliana accessions, and the corresponding testcrosses with these two original accessions were used for the development and validation of machine learning models to predict the biomass of hybrids. Genetic and metabolic information of the RILs served as predictors. Feature selection reduced the number of variables (genetic and metabolic markers) in the models by more than 80% without impairing the predictive power. Thus, potential biomarkers have been revealed. Metabolites were shown to bear information on inherited macroscopic phenotypes. This proof of concept could be interesting for breeders. The example population exhibits substantial mid-parent biomass heterosis. The results of feature selection could therefore be used to shed light on the origin of heterosis. In this respect, mainly dominance effects were detected.
In recent decades, astronomy has seen a boom in large-scale stellar surveys of the Galaxy. The detailed information obtained about millions of individual stars in the Milky Way is bringing us a step closer to answering one of the most outstanding questions in astrophysics: how do galaxies form and evolve? The Milky Way is the only galaxy where we can dissect many stars into their high-dimensional chemical composition and complete phase space, which analogously as fossil records can unveil the past history of the genesis of the Galaxy. The processes that lead to large structure formation, such as the Milky Way, are critical for constraining cosmological models; we call this line of study Galactic archaeology or near-field cosmology.
At the core of this work, we present a collection of efforts to chemically and dynamically characterise the disks and bulge of our Galaxy. The results we present in this thesis have only been possible thanks to the advent of the Gaia astrometric satellite, which has revolutionised the field of Galactic archaeology by precisely measuring the positions, parallax distances and motions of more than a billion stars. Another, though not less important, breakthrough is the APOGEE survey, which has observed spectra in the near-infrared peering into the dusty regions of the Galaxy, allowing us to determine detailed chemical abundance patterns in hundreds of thousands of stars. To accurately depict the Milky Way structure, we use and develop the Bayesian isochrone fitting tool/code called StarHorse; this software can predict stellar distances, extinctions and ages by combining astrometry, photometry and spectroscopy based on stellar evolutionary models. The StarHorse code is pivotal to calculating distances where Gaia parallaxes alone cannot allow accurate estimates.
We show that by combining Gaia, APOGEE, photometric surveys and using StarHorse, we can produce a chemical cartography of the Milky way disks from their outermost to innermost parts. Such a map is unprecedented in the inner Galaxy. It reveals a continuity of the bimodal chemical pattern previously detected in the solar neighbourhood, indicating two populations with distinct formation histories. Furthermore, the data reveals a chemical gradient within the thin disk where the content of 𝛼-process elements and metals is higher towards the centre. Focusing on a sample in the inner MW we confirm the extension of the chemical duality to the innermost regions of the Galaxy. We find stars with bar shape orbits to show both high- and low-𝛼 abundances, suggesting the bar formed by secular evolution trapping stars that already existed. By analysing the chemical orbital space of the inner Galactic regions, we disentangle the multiple populations that inhabit this complex region. We reveal the presence of the thin disk, thick disk, bar, and a counter-rotating population, which resembles the outcome of a perturbed proto-Galactic disk. Our study also finds that the inner Galaxy holds a high quantity of super metal-rich stars up to three times solar suggesting it is a possible repository of old super-metal-rich stars found in the solar neighbourhood.
We also enter into the complicated task of deriving individual stellar ages. With StarHorse, we calculate the ages of main-sequence turn-off and sub-giant stars for several public spectroscopic surveys. We validate our results by investigating linear relations between chemical abundances and time since the 𝛼 and neutron capture elements are sensitive to age as a reflection of the different enrichment timescales of these elements. For further study of the disks in the solar neighbourhood, we use an unsupervised machine learning algorithm to delineate a multidimensional separation of chrono-chemical stellar groups revealing the chemical thick disk, the thin disk, and young 𝛼-rich stars. The thick disk is shown to have a small age dispersion indicating its fast formation contrary to the thin disk that spans a wide range of ages.
With groundbreaking data, this thesis encloses a detailed chemo-dynamical view of the disk and bulge of our Galaxy. Our findings on the Milky Way can be linked to the evolution of high redshift disk galaxies, helping to solve the conundrum of galaxy formation.
Many widely used observational data sets are comprised of several overlapping instrument records. While data inter-calibration techniques often yield continuous and reliable data for trend analysis, less attention is generally paid to maintaining higher-order statistics such as variance and autocorrelation. A growing body of work uses these metrics to quantify the stability or resilience of a system under study and potentially to anticipate an approaching critical transition in the system. Exploring the degree to which changes in resilience indicators such as the variance or autocorrelation can be attributed to non-stationary characteristics of the measurement process – rather than actual changes in the dynamical properties of the system – is important in this context. In this work we use both synthetic and empirical data to explore how changes in the noise structure of a data set are propagated into the commonly used resilience metrics lag-one autocorrelation and variance. We focus on examples from remotely sensed vegetation indicators such as vegetation optical depth and the normalized difference vegetation index from different satellite sources. We find that time series resulting from mixing signals from sensors with varied uncertainties and covering overlapping time spans can lead to biases in inferred resilience changes. These biases are typically more pronounced when resilience metrics are aggregated (for example, by land-cover type or region), whereas estimates for individual time series remain reliable at reasonable sensor signal-to-noise ratios. Our work provides guidelines for the treatment and aggregation of multi-instrument data in studies of critical transitions and resilience.
Aus dem Inhalt:
- Menschenrechtsklagen vor Zivilgerichten in Deutschland – Eine Bestandsaufnahme der methodisch-rechtspolitischen Ansätze im Internationalen Privatrecht (IPR)
- Das Vorsorgeprinzip – ein unterschätzter Bestandteil menschenrechtlicher Klimaklagen?
- Der Menschenrechtsausschuss der Vereinten Nationen und die Klimakrise – Die Entscheidung Billy et al. gegen Australien und ihr Beitrag zur „Begrünung“ des Menschenrechtsschutzes
Background
The association between bivariate variables may not necessarily be homogeneous throughout the whole range of the variables. We present a new technique to describe inhomogeneity in the association of bivariate variables.
Methods
We consider the correlation of two normally distributed random variables. The 45° diagonal through the origin of coordinates represents the line on which all points would lie if the two variables completely agreed. If the two variables do not completely agree, the points will scatter on both sides of the diagonal and form a cloud. In case of a high association between the variables, the band width of this cloud will be narrow, in case of a low association, the band width will be wide. The band width directly relates to the magnitude of the correlation coefficient. We then determine the Euclidean distances between the diagonal and each point of the bivariate correlation, and rotate the coordinate system clockwise by 45°. The standard deviation of all Euclidean distances, named “global standard deviation”, reflects the band width of all points along the former diagonal. Calculating moving averages of the standard deviation along the former diagonal results in “locally structured standard deviations” and reflect patterns of “locally structured correlations (LSC)”. LSC highlight inhomogeneity of bivariate correlations. We exemplify this technique by analyzing the association between body mass index (BMI) and hip circumference (HC) in 6313 healthy East German adults aged 18 to 70 years.
Results
The correlation between BMI and HC in healthy adults is not homogeneous. LSC is able to identify regions where the predictive power of the bivariate correlation between BMI and HC increases or decreases, and highlights in our example that slim people have a higher association between BMI and HC than obese people.
Conclusion
Locally structured correlations (LSC) identify regions of higher or lower than average correlation between two normally distributed variables.
Physical activity and exercise are effective approaches in prevention and therapy of multiple diseases. Although the specific characteristics of lengthening contractions have the potential to be beneficial in many clinical conditions, eccentric training is not commonly used in clinical populations with metabolic, orthopaedic, or neurologic conditions. The purpose of this pilot study is to investigate the feasibility, functional benefits, and systemic responses of an eccentric exercise program focused on the trunk and lower extremities in people with low back pain (LBP) and multiple sclerosis (MS). A six-week eccentric training program with three weekly sessions is performed by people with LBP and MS. The program consists of ten exercises addressing strength of the trunk and lower extremities. The study follows a four-group design (N = 12 per group) in two study centers (Israel and Germany): three groups perform the eccentric training program: A) control group (healthy, asymptomatic); B) people with LBP; C) people with MS; group D (people with MS) receives standard care physiotherapy. Baseline measurements are conducted before first training, post-measurement takes place after the last session both comprise blood sampling, self-reported questionnaires, mobility, balance, and strength testing. The feasibility of the eccentric training program will be evaluated using quantitative and qualitative measures related to the study process, compliance and adherence, safety, and overall program assessment. For preliminary assessment of potential intervention effects, surrogate parameters related to mobility, postural control, muscle strength and systemic effects are assessed. The presented study will add knowledge regarding safety, feasibility, and initial effects of eccentric training in people with orthopaedic and neurological conditions. The simple exercises, that are easily modifiable in complexity and intensity, are likely beneficial to other populations. Thus, multiple applications and implementation pathways for the herein presented training program are conceivable.
Recent research suggests that design thinking practices may foster the development of needed capabilities in new digitalised landscapes. However, existing publications represent individual contributions, and we lack a holistic understanding of the value of design thinking in a digital world. No review, to date, has offered a holistic retrospection of this research. In response, in this bibliometric review, we aim to shed light on the intellectual structure of multidisciplinary design thinking literature related to capabilities relevant to the digital world in higher education and business settings, highlight current trends and suggest further studies to advance theoretical and empirical underpinnings. Our study addresses this aim using bibliometric methods—bibliographic coupling and co-word analysis as they are particularly suitable for identifying current trends and future research priorities at the forefront of the research. Overall, bibliometric analyses of the publications dealing with the related topics published in the last 10 years (extracted from the Web of Science database) expose six trends and two possible future research developments highlighting the expanding scope of the design thinking scientific field related to capabilities required for the (more sustainable and human-centric) digital world. Relatedly, design thinking becomes a relevant approach to be included in higher education curricula and human resources training to prepare students and workers for the changing work demands. This paper is well-suited for education and business practitioners seeking to embed design thinking capabilities in their curricula and for design thinking and other scholars wanting to understand the field and possible directions for future research.
Inverted perovskite solar cells still suffer from significant non-radiative recombination losses at the perovskite surface and across the perovskite/C₆₀ interface, limiting the future development of perovskite-based single- and multi-junction photovoltaics. Therefore, more effective inter- or transport layers are urgently required. To tackle these recombination losses, we introduce ortho-carborane as an interlayer material that has a spherical molecular structure and a three-dimensional aromaticity. Based on a variety of experimental techniques, we show that ortho-carborane decorated with phenylamino groups effectively passivates the perovskite surface and essentially eliminates the non-radiative recombination loss across the perovskite/C₆₀ interface with high thermal stability. We further demonstrate the potential of carborane as an electron transport material, facilitating electron extraction while blocking holes from the interface. The resulting inverted perovskite solar cells deliver a power conversion efficiency of over 23% with a low non-radiative voltage loss of 110 mV, and retain >97% of the initial efficiency after 400 h of maximum power point tracking. Overall, the designed carborane based interlayer simultaneously enables passivation, electron-transport and hole-blocking and paves the way toward more efficient and stable perovskite solar cells.
Inverted perovskite solar cells still suffer from significant non-radiative recombination losses at the perovskite surface and across the perovskite/C₆₀ interface, limiting the future development of perovskite-based single- and multi-junction photovoltaics. Therefore, more effective inter- or transport layers are urgently required. To tackle these recombination losses, we introduce ortho-carborane as an interlayer material that has a spherical molecular structure and a three-dimensional aromaticity. Based on a variety of experimental techniques, we show that ortho-carborane decorated with phenylamino groups effectively passivates the perovskite surface and essentially eliminates the non-radiative recombination loss across the perovskite/C₆₀ interface with high thermal stability. We further demonstrate the potential of carborane as an electron transport material, facilitating electron extraction while blocking holes from the interface. The resulting inverted perovskite solar cells deliver a power conversion efficiency of over 23% with a low non-radiative voltage loss of 110 mV, and retain >97% of the initial efficiency after 400 h of maximum power point tracking. Overall, the designed carborane based interlayer simultaneously enables passivation, electron-transport and hole-blocking and paves the way toward more efficient and stable perovskite solar cells.
Achilles tendinopathy (AT) is a debilitating injury in athletes, especially for those engaged in repetitive stretch-shortening cycle activities. Clinical risk factors are numerous, but it has been suggested that altered biomechanics might be associated with AT. No systematic review has been conducted investigating these biomechanical alterations in specifically athletic populations. Therefore, the aim of this systematic review was to compare the lower-limb biomechanics of athletes with AT to athletically matched asymptomatic controls. Databases were searched for relevant studies investigating biomechanics during gait activities and other motor tasks such as hopping, isolated strength tasks, and reflex responses. Inclusion criteria for studies were an AT diagnosis in at least one group, cross-sectional or prospective data, at least one outcome comparing biomechanical data between an AT and healthy group, and athletic populations. Studies were excluded if patients had Achilles tendon rupture/surgery, participants reported injuries other than AT, and when only within-subject data was available.. Effect sizes (Cohen's d) with 95% confidence intervals were calculated for relevant outcomes. The initial search yielded 4,442 studies. After screening, twenty studies (775 total participants) were synthesised, reporting on a wide range of biomechanical outcomes. Females were under-represented and patients in the AT group were three years older on average. Biomechanical alterations were identified in some studies during running, hopping, jumping, strength tasks and reflex activity. Equally, several biomechanical variables studied were not associated with AT in included studies, indicating a conflicting picture. Kinematics in AT patients appeared to be altered in the lower limb, potentially indicating a pattern of “medial collapse”. Muscular activity of the calf and hips was different between groups, whereby AT patients exhibited greater calf electromyographic amplitudes despite lower plantar flexor strength. Overall, dynamic maximal strength of the plantar flexors, and isometric strength of the hips might be reduced in the AT group. This systematic review reports on several biomechanical alterations in athletes with AT. With further research, these factors could potentially form treatment targets for clinicians, although clinical approaches should take other contributing health factors into account. The studies included were of low quality, and currently no solid conclusions can be drawn.
Intuitively, strongly constraining contexts should lead to stronger probabilistic representations of sentences in memory. Encountering unexpected words could therefore be expected to trigger costlier shifts in these representations than expected words. However, psycholinguistic measures commonly used to study probabilistic processing, such as the N400 event-related potential (ERP) component, are sensitive to word predictability but not to contextual constraint. Some research suggests that constraint-related processing cost may be measurable via an ERP positivity following the N400, known as the anterior post-N400 positivity (PNP). The PNP is argued to reflect update of a sentence representation and to be distinct from the posterior P600, which reflects conflict detection and reanalysis. However, constraint-related PNP findings are inconsistent. We sought to conceptually replicate Federmeier et al. (2007) and Kuperberg et al. (2020), who observed that the PNP, but not the N400 or the P600, was affected by constraint at unexpected but plausible words. Using a pre-registered design and statistical approach maximising power, we demonstrated a dissociated effect of predictability and constraint: strong evidence for predictability but not constraint in the N400 window, and strong evidence for constraint but not predictability in the later window. However, the constraint effect was consistent with a P600 and not a PNP, suggesting increased conflict between a strong representation and unexpected input rather than greater update of the representation. We conclude that either a simple strong/weak constraint design is not always sufficient to elicit the PNP, or that previous PNP constraint findings could be an artifact of smaller sample size.
Intuitively, strongly constraining contexts should lead to stronger probabilistic representations of sentences in memory. Encountering unexpected words could therefore be expected to trigger costlier shifts in these representations than expected words. However, psycholinguistic measures commonly used to study probabilistic processing, such as the N400 event-related potential (ERP) component, are sensitive to word predictability but not to contextual constraint. Some research suggests that constraint-related processing cost may be measurable via an ERP positivity following the N400, known as the anterior post-N400 positivity (PNP). The PNP is argued to reflect update of a sentence representation and to be distinct from the posterior P600, which reflects conflict detection and reanalysis. However, constraint-related PNP findings are inconsistent. We sought to conceptually replicate Federmeier et al. (2007) and Kuperberg et al. (2020), who observed that the PNP, but not the N400 or the P600, was affected by constraint at unexpected but plausible words. Using a pre-registered design and statistical approach maximising power, we demonstrated a dissociated effect of predictability and constraint: strong evidence for predictability but not constraint in the N400 window, and strong evidence for constraint but not predictability in the later window. However, the constraint effect was consistent with a P600 and not a PNP, suggesting increased conflict between a strong representation and unexpected input rather than greater update of the representation. We conclude that either a simple strong/weak constraint design is not always sufficient to elicit the PNP, or that previous PNP constraint findings could be an artifact of smaller sample size.
Background
Eating in absence of hunger is quite common and often associated with an increased energy intake co-existent with a poorer food choice. Intuitive eating (IE), i.e., eating in accordance with internal hunger and satiety cues, may protect from overeating. IE, however, requires accurate perception and processing of one’s own bodily signals, also referred to as interoceptive sensitivity. Training interoceptive sensitivity might therefore be an effective method to promote IE and prevent overeating. As most studies on eating behavior are conducted in younger adults and close social relationships influence health-related behavior, this study focuses on middle-aged and older couples.
Methods
The present pilot randomized intervention study aims at investigating the feasibility and effectiveness of a 21-day mindfulness-based training program designed to increase interoceptive sensitivity. A total of N = 60 couples participating in the NutriAct Family Study, aged 50–80 years, will be recruited. This randomized-controlled intervention study comprises three measurement points (pre-intervention, post-intervention, 4-week follow-up) and a 21-day training that consists of daily mindfulness-based guided audio exercises (e.g., body scan). A three-arm intervention study design is applied to compare two intervention groups (training together as a couple vs. training alone) with a control group (no training). Each measurement point includes the assessment of self-reported and objective indicators of interoceptive sensitivity (primary outcome), self-reported indicators of intuitive and maladaptive eating (secondary outcomes), and additional variables. A training evaluation applying focus group discussions will be conducted to assess participants’ overall acceptance of the training and its feasibility.
Discussion
By investigating the feasibility and effectiveness of a mindfulness-based training program to increase interoceptive sensitivity, the present study will contribute to a deeper understanding of how to promote healthy eating in older age.
Anomalous-diffusion, the departure of the spreading dynamics of diffusing particles from the traditional law of Brownian-motion, is a signature feature of a large number of complex soft-matter and biological systems. Anomalous-diffusion emerges due to a variety of physical mechanisms, e.g., trapping interactions or the viscoelasticity of the environment. However, sometimes systems dynamics are erroneously claimed to be anomalous, despite the fact that the true motion is Brownian—or vice versa. This ambiguity in establishing whether the dynamics as normal or anomalous can have far-reaching consequences, e.g., in predictions for reaction- or relaxation-laws. Demonstrating that a system exhibits normal- or anomalous-diffusion is highly desirable for a vast host of applications. Here, we present a criterion for anomalous-diffusion based on the method of power-spectral analysis of single trajectories. The robustness of this criterion is studied for trajectories of fractional-Brownian-motion, a ubiquitous stochastic process for the description of anomalous-diffusion, in the presence of two types of measurement errors. In particular, we find that our criterion is very robust for subdiffusion. Various tests on surrogate data in absence or presence of additional positional noise demonstrate the efficacy of this method in practical contexts. Finally, we provide a proof-of-concept based on diverse experiments exhibiting both normal and anomalous-diffusion.
Creative thinking is an indispensable cognitive skill that is becoming increasingly important. In the present research, we tested the impact of games on creativity and emotions in a between-subject online experiment with four conditions (N = 658). (1) participants played a simple puzzle game that allowed many solutions (priming divergent thinking); (2) participants played a short game that required one fitting solution (priming convergent thinking); (3) participants performed mental arithmetic; (4) passive control condition. Results show that divergent and convergent creativity were higher after playing games and lower after mental arithmetic. Positive emotions did not function as a mediator, even though they were also heightened after playing the games and lower after mental arithmetic. However, contrary to previous research, we found no direct effect of emotions, creative self-efficacy, and growth- vs. fixed on creative performance. We discuss practical implications for digital learning and application settings.
Technologically important, environmentally friendly InP quantum dots (QDs) typically used as green and red emitters in display devices can achieve exceptional photoluminescence quantum yields (PL QYs) of near-unity (95-100%) when the-state-of-the-art core/shell heterostructure of the ZnSe inner/ZnS outer shell is elaborately applied. Nevertheless, it has only led to a few industrial applications as QD liquid crystal display (QD–LCD) which is applied to blue backlight units, even though QDs has a lot of possibilities that able to realize industrially feasible applications, such as QD light-emitting diodes (QD‒LEDs) and luminescence solar concentrator (LSC), due to their functionalizable characteristics.
Before introducing the main research, the theoretical basis and fundamentals of QDs are described in detail on the basis of the quantum mechanics and experimental synthetic results, where a concept of QD and colloidal QD, a type-I core/shell structure, a transition metal doped semiconductor QDs, the surface chemistry of QD, and their applications (LSC, QD‒LEDs, and EHD jet printing) are sequentially elucidated for better understanding. This doctoral thesis mainly focused on the connectivity between QD materials and QD devices, based on the synthesis of InP QDs that are composed of inorganic core (core/shell heterostructure) and organic shell (surface ligands on the QD surface). In particular, as for the former one (core/shell heterostructure), the ZnCuInS mid-shell as an intermediate layer is newly introduced between a Cu-doped InP core and a ZnS shell for LSC devices. As for the latter one (surface ligands), the ligand effect by 1-octanethiol and chloride ion are investigated for the device stability in QD‒LEDs and the printability of electro-hydrodynamic (EHD) jet printing system, in which this research explores the behavior of surface ligands, based on proton transfer mechanism on the QD surface.
Chapter 3 demonstrates the synthesis of strain-engineered highly emissive Cu:InP/Zn–Cu–In–S (ZCIS)/ZnS core/shell/shell heterostructure QDs via a one-pot approach. When this unconventional combination of a ZCIS/ZnS double shelling scheme is introduced to a series of Cu:InP cores with different sizes, the resulting Cu:InP/ZCIS/ZnS QDs with a tunable near-IR PL range of 694–850 nm yield the highest-ever PL QYs of 71.5–82.4%. These outcomes strongly point to the efficacy of the ZCIS interlayer, which makes the core/shell interfacial strain effectively alleviated, toward high emissivity. The presence of such an intermediate ZCIS layer is further examined by comparative size, structural, and compositional analyses. The end of this chapter briefly introduces the research related to the LSC devices, fabricated from Cu:InP/ZCIS/ZnS QDs, currently in progress.
Chapter 4 mainly deals with ligand effect in 1-octanethiol passivation of InP/ZnSe/ZnS QDs in terms of incomplete surface passivation during synthesis. This chapter demonstrates the lack of anionic carboxylate ligands on the surface of InP/ZnSe/ZnS quantum dots (QDs), where zinc carboxylate ligands can be converted to carboxylic acid or carboxylate ligands via proton transfer by 1-octanethiol. The as-synthesized QDs initially have an under-coordinated vacancy surface, which is passivated by solvent ligands such as ethanol and acetone. Upon exposure of 1-octanethiol to the QD surface, 1-octanthiol effectively induces the surface binding of anionic carboxylate ligands (derived from zinc carboxylate ligands) by proton transfer, which consequently exchanges ethanol and acetone ligands that bound on the incomplete QD surface. The systematic chemical analyses, such as thermogravimetric analysis‒mass spectrometry and proton nuclear magnetic resonance spectroscopy, directly show the interplay of surface ligands, and it associates with QD light-emitting diodes (QD‒LEDs).
Chapter 5 shows the relation between material stability of QDs and device stability of QD‒LEDs through the investigation of surface chemistry and shell thickness. In typical III–V colloidal InP quantum dots (QDs), an inorganic ZnS outermost shell is used to provide stability when overcoated onto the InP core. However, this work presents a faster photo-degradation of InP/ZnSe/ZnS QDs with a thicker ZnS shell than that with a thin ZnS shell when 1-octanethiol was applied as a sulfur source to form ZnS outmost shell. Herein, 1-octanethiol induces the form of weakly-bound carboxylate ligand via proton transfer on the QD surface, resulting in a faster degradation at UV light even though a thicker ZnS shell was formed onto InP/ZnSe QDs. Detailed insight into surface chemistry was obtained from proton nuclear magnetic resonance spectroscopy and thermogravimetric analysis–mass spectrometry. However, the lifetimes of the electroluminescence devices fabricated from InP/ZnSe/ZnS QDs with a thick or a thin ZnS shell show surprisingly the opposite result to the material stability of QDs, where the QD light-emitting diodes (QD‒LEDs) with a thick ZnS shelled QDs maintained its luminance more stable than that with a thin ZnS shelled QDs. This study elucidates the degradation mechanism of the QDs and the QD light-emitting diodes based on the results and discuss why the material stability of QDs is different from the lifetime of QD‒LEDs.
Chapter 6 suggests a method how to improve a printability of EHD jet printing when QD materials are applied to QD ink formulation, where this work introduces the application of GaP mid-shelled InP QDs as a role of surface charge in EHD jet printing technique. In general, GaP intermediate shell has been introduced in III–V colloidal InP quantum dots (QDs) to enhance their thermal stability and quantum efficiency in the case of type-I core/shell/shell heterostructure InP/GaP/ZnSeS QDs. Herein, these highly luminescent InP/GaP/ZnSeS QDs were synthesized and applied to EHD jet printing, by which this study demonstrates that unreacted Ga and Cl ions on the QD surface induce the operating voltage of cone jet and cone jet formation to be reduced and stabilized, respectively. This result indicates GaP intermediate shell not only improves PL QY and thermal stability of InP QDs but also adjusts the critical flow rate required for cone-jet formation. In other words, surface charges of quantum dots can have a significant role in forming cone apex in the EHD capillary nozzle. For an industrially convenient validation of surface charges on the QD surface, Zeta potential analyses of QD solutions as a simple method were performed, as well as inductively coupled plasma optical emission spectrometry (ICP-OES) for a composition of elements.
Beyond the generation of highly emissive InP QDs with narrow FWHM, these studies talk about the connection between QD material and QD devices not only to make it a vital jumping-off point for industrially feasible applications but also to reveal from chemical and physical standpoints the origin that obstructs the improvement of device performance experimentally and theoretically.
The last years have been affected by Covid-19 and the international emergency mecha-nism to deal with health-related threats. The effects of this period manifested differ-ently worldwide, depending on matters such as international relations, national policies, power dynamics etc. Additionally, the impact of this time will likely have long-term effects which are yet to be known. This paper gives a critical overview of the Public Health Emergency of International Concern (PHEIC) mechanism in the context of Covid-19. It does so by explaining the legal framework for states of emergency, specifically in the context of a PHEIC, while considering its restrictions and limitations on human rights. It further outlines issues in the manifestation of global protections and limitations on human rights during Covid-19. Lastly, considering the likelihood of future PHEICs and the known systemic obstructions, this paper offers ways to im-prove this mechanism from a holistic, non-zero-sum perspective.
This dissertation aimed to determine differential expressed miRNAs in the context of chronic pain in polyneuropathy. For this purpose, patients with chronic painful polyneuropathy were compared with age matched healthy patients. Taken together, all miRNA pre library preparation quality controls were successful and none of the samples was identified as an outlier or excluded for library preparation. Pre sequencing quality control showed that library preparation worked for all samples as well as that all samples were free of adapter dimers after BluePippin size selection and reached the minimum molarity for further processing. Thus, all samples were subjected to sequencing. The sequencing control parameters were in their optimal range and resulted in valid sequencing results with strong sample to sample correlation for all samples. The resulting FASTQ file of each miRNA library was analyzed and used to perform a differential expression analysis. The differentially expressed and filtered miRNAs were subjected to miRDB to perform a target prediction. Three of those four miRNAs were downregulated: hsa-miR-3135b, hsa-miR-584-5p and hsa-miR-12136, while one was upregulated: hsa-miR-550a-3p. miRNA target prediction showed that chronic pain in polyneuropathy might be the result of a combination of miRNA mediated high blood flow/pressure and neural activity dysregulations/disbalances. Thus, leading to the promising conclusion that these four miRNAs could serve as potential biomarkers for the diagnosis of chronic pain in polyneuropathy.
Since TRPV1 seems to be one of the major contributors of nociception and is associated with neuropathic pain, the influence of PKA phosphorylated ARMS on the sensitivity of TRPV1 as well as the part of AKAP79 during PKA phosphorylation of ARMS was characterized. Therefore, possible PKA-sites in the sequence of ARMS were identified. This revealed five canonical PKA-sites: S882, T903, S1251/52, S1439/40 and S1526/27. The single PKA-site mutants of ARMS revealed that PKA-mediated ARMS phosphorylation seems not to influence the interaction rate of TRPV1/ARMS. While phosphorylation of ARMST903 does not increase the interaction rate with TRPV1, ARMSS1526/27 is probably not phosphorylated and leads to an increased interaction rate. The calcium flux measurements indicated that the higher the interaction rate of TRPV1/ARMS, the lower the EC50 for capsaicin of TRPV1, independent of the PKA phosphorylation status of ARMS. In addition, the western blot analysis confirmed the previously observed TRPV1/ARMS interaction. More importantly, AKAP79 seems to be involved in the TRPV1/ARMS/PKA signaling complex. To overcome the problem of ARMS-mediated TRPV1 sensitization by interaction, ARMS was silenced by shRNA. ARMS silencing resulted in a restored TRPV1 desensitization without affecting the TRPV1 expression and therefore could be used as new topical therapeutic analgesic alternative to stop ARMS mediated TRPV1 sensitization.
Nutrition, size, and tempo
(2023)
Nutrition is a prerequisite, but not a regulator of growth. Growth is defined as increase in size over time. The understanding of growth includes an understanding of the binary concept of physical time and individual tempo. Excess food causes tempo acceleration. Food restriction delays tempo. Tempo reflects the pace of life. It is a dynamic physical response to a broad spectrum of social, economic, political, and emotional (SEPE) factors and can affect life expectancy. Variations in tempo create distortions of the z-score patterns of height and weight. Illness or intermediate food shortage lead to intermediate halts in development and create short dips in the z-score patterns. Children who develop throughout life at delayed pace usually run at lower z-scores for height and weight, and show a characteristic adolescent trough; children who develop throughout life at faster than average pace usually run at higher z-scores and show a characteristic adolescent peak in their z-score patterns. During adolescence, almost half of the height variance is due to tempo variation. There is not one tempo for the whole body. Different organ systems grow and mature at different pace.
What does stunting tell us?
(2023)
Stunting is commonly linked with undernutrition. Yet, already after World War I, German pediatricians questioned this link and stated that no association exists between nutrition and height. Recent analyses within different populations of Low- and middle-income countries with high rates of stunted children failed to support the assumption that stunted children have a low BMI and skinfold sickness as signs of severe caloric deficiency. So, stunting is not a synonym of malnutrition. Parental education level has a positive influence on body height in stunted populations, e.g., in India and in Indonesia. Socially disadvantaged children tend to be shorter and lighter than children from affluent families.
Humans are social mammals; they regulate growth similar to other social mammals. Also in humans, body height is strongly associated with the position within the social hierarchy, reflecting the personal and group-specific social, economic, political, and emotional environment. These non-nutritional impact factors on growth are summarized by the concept of SEPE (Social-Economic-Political-Emotional) factors. SEPE reflects on prestige, dominance-subordination, social identity, and ego motivation of individuals and social groups.
Functional materials, also called "Smart Materials", are described by their ability to fulfill a desired task through targeted interaction with its environment. Due to this functional integration, such materials are of increased interest, especially in areas where the increasing micronization of components is required. Modern manufacturing processes (e.g. microfluidics) and the availability of a wide variety of functional materials (e.g. shape memory materials) now enable the production of particle-based switching components. This category includes micropumps and microvalves, whose basic function is the active control of liquid flows. One approach in realizing those microcomponents as pursued by this work, enables variable size-switching of water-filled microballoons by implementing a stimulus-sensitive switching motif in the capsule's membrane shell, while being under the influence of a constant driving force. The switching motif with its gatekeeper function has a critical influence on one or more material parameters, which modulate the capsule's resistance against the driving force in microballoon expansion process. The advantage of this concept is that even non-variable analyte conditions, such as concentration levels of ions, can be capitalized to generate external force fields that, under the control of the membrane, cause an inflation of the microballoon by an osmotically driven water influx. In case of osmotic pressure gradients as the driving force for the capsule expansion, material parameters associated with the gatekeeper function are specifically the permeability and the mechanical stiffness of the shell material. While a modulation of the shell permeability could be utilized to kinetically impede the water influx on large time scales, a modulation of the shell's mechanical stiffness even might be utilized to completely prevent the capsule inflation due to a possible non-deformability beneath a certain threshold pressure. In polymer networks, which are a suitable material class for the demanded capsule shell because of their excellent elasticity, both the permeability and the mechanical properties are strongly influenced by the crystallinity of the material. Since the permeability is effectively reduced with increasing crystallinity, while the mechanical stiffness is simultaneously greatly increased, both effects point in the same direction in terms of their functional relationship. For this reason and due to a reversible and contactless modulation of the membrane crystallinity by heat input, crystallites may be suitable switching motifs for controlling the capsule expansion. As second design element of reversible expandable microballoons, the capsule geometry, defined by an aqueous core enveloped by the temperature-sensitive polymer network membrane, should allow an osmotic pressure gradient across the membrane layer. The strength of the inflation pressure and the associated inflation velocity upon membrane melting should be controlled by the salt concentration within the aqueous core, while a turn in the osmotic gradient should furthermore allow the reversible process of capsule deflation. Therefore, it should be possible to build either microvalves and micropumps, while their intended action of either pumping or valving is determined by their state of expansion and the direction of the osmotic pressure gradient.. Microballoons of approximately 300 µm in diameter were formed via droplet-based microfluidics from double-emulsion templates (w/o/w). The elastomeric capsule membrane was formed by photo-crosslinking of methacrylate (MA) functionalized oligo(ε-caprolactone) precursors (≈ 3.8 MA-arms, Mn ≈ 12000 g mol-1) within the organic medium layer (o) via UV-exposure after droplet-formation. After removal of the toluene/chloroform mixture by slow extraction via the continuous aqueous phase, the capsules solidified under the development of a characteristic "mushroom"-like shape at specific experimental conditions (e.g. λ = 308 nm, 57 mJ·s-1·cm-2, 16 min). It could be furthermore shown that in dependency to the process parameters: oligomer concentration and curing-time also spherical capsules were accessible. Long curing-times and high oligomer concentrations at a fixed light-intensity favored the formation of "mushroom"-like capsules, whereas the contrary led to spherical shaped capsules. A comparative study on thin polymer network films of same composition and equal treatment proved a correlation between the film's crosslink density and their contraction capability, while stronger crosslinked polymer networks showed a stronger contraction after solvent removal. In combination with observations during capsule solidification via light-microscopy, where a continuous shaping from almost spherical crosslinked templates to "mushroom"-shaped and solidified capsules was stated, the following mechanism was proposed. In case of low oligomer contents and short curing-times, the contraction of the capsule shell during solvent removal is strongly diminished due to a low degree of crosslinking. Therefore, the solidifying shell could freely collapse onto the aqueous core. In the other case, high oligomer concentrations and long curing-times will favor the formation of highly crosslinked capsule membranes with a strong contraction capability. Due to an observed decentered location of the aqueous core within the swollen polymer network, an uneven radial stress along the capsule's circumference is exerted to the incompressible core. This lead to an uneven contraction during solvent removal and a directed flow of the core fluid into the direction of the minimal stress vector. In consequence, the initially thicker spherical cap contracts, whereas the opposing thinner spherical cap get stretched. The "mushroom"-shape over some advantages over their spherical shaped counterparts, why they were selected for the further experiments. Besides the necessity of a high density of crosslinking for the purpose of extraordinary elasticity and toughness, the form-anisotropy promotes a faster microballoon expandability due to a partial reduction of the membrane thickness. Additionally, pre-stretched regions of thin thickness might provide a better resistance against inflation pressure than spherical but non-stretched capsules of equal membrane thickness. The resulting "mushroom"-shaped microcapsules exhibited a melting point of Tm ≈ 50 - 60 °C and a degree of crystallinity of Xc ≈ 29 - 38 % depending on the membrane thickness and internal salt content, which is slightly lower than for the non-crosslinked oligomer and reasoned by a limited chain mobility upon crosslinking. Nonetheless, the melting transition of the polymer network was associated with a strong drop in its mechanical stiffness, which was shown to have a strong influence on the osmotic driven expansion of the microcapsules. Capsules that were subjected to osmotic pressures between 1.5 and 4.7 MPa did not expand if the temperature was well below the melting point of the capsule's membrane, i.e. at room temperature. In contrast, a continuous expansion, while approaching asymptotically to a final capsule size, was observed if the temperature exceeded the melting point, i.e. 60 °C. Microballoons, which were kept for 56 days at ∆Π = 1.5 MPa and room temperature, did not change significantly in diameter, why the impact of the mechanical stiffness on the expansion behavior is considered to be the greater than the influence of the shell permeability. The time-resolved expansion behavior of the microballoons above their Tm was subsequently modeled, using difusion equations that were corrected for shape anisotropy and elastic restoring forces. A shape-related and expansion dependent pre-factor was used to dynamically address the influence of the shell thickness differences along the circumference on the inflation velocity, whereas the microballoon's elastic contraction upon inflation was rendered by the inclusion of a hyperelastic constitutive model. An important finding resulting from this model was the pronounced increase in inflation velocity compared to hypothetical capsules with a homogeneous shell thickness, which stresses the benefit of employing shape anisotropic balloon-like capsules in this study. Furthermore, the model was able to predict the finite expandability on basis of entropy-elastic recovery forces and strain-hardening effects. A comparison of six different microballoons with different shell thicknesses and internal salt contents showed the linear relationship between the volumetric expansion, the shell thickness and the applied osmotic pressure, as represented by the model. As the proposed model facilitates the prediction of the expansion kinetics depending on the membranes mechanical and diffusional characteristics, it might be a screening tool for future material selections. In course of the microballoon expansion process, capsules of intermediate diameters could be isolated by recrystallization of the membrane, which is mainly caused by a restoration of the membrane's mechanical stiffness and is otherwise difficult to achieve with other stimuli-sensitive systems. The capsule's crystallinity of intermediate expansion states was nearly unchanged, whereas the lamellar crystal size tends to decreased with the expansion ratio. Therefore, it was assumed that the elastic modulus was only minimally altered and might increased due to the networks segment-chain extension. In addition to the volume increase achieved by inflation, a turn in the osmotic gradient also facilitated the reversible deflation, which was shown in inflation/deflation cycles. These both characteristics of the introduced microballoons are important parameter regarding the realization of micropumps and microvalves. The fixation of expanded microcapsules via recrystallization enabled the storage of entropy-elastic strain-energy, which could be utilized for pumping actions in non-aqueous media. Here, the pumping velocity depended on both, the type of surrounding medium and the applied temperature. Surrounding media that supported the fast transport of pumped liquid showed an accelerated deflation, while high temperatures further accelerate the pumping velocity. Very fast rejection of the incorporated payload was furthermore realized with pierced expanded microballoons, which were subjected to temperatures above their Tm. The possible fixation of intermediate particle sizes provide opportunities for vent constructions that allowed the precise adjustment of specific flow-rates and multiple valve openings and closings. A valve construction was realized by the insertion of a single or multiple microballoons in a microfluidic channel. A complete and a partial closing of the microballoon-valves was demonstrated as a function of the heating period. In this context, a difference between the inflation and deflation velocity was stated, summarizing slower expansion kinetics. Overall, microballoons, which presented both on-demand pumping and reversible valving by a temperature-triggered change in the capsule's volume, might be suitable components that help to design fully integrated LOC devices, due to the implementation of the control switch and controllable inflation/deflation kinetics. In comparison to other state of the art stimuli-sensitive materials, one has to highlight the microballoons capability of stabilizing almost continuously intermediate capsule sizes by simple recrystallization of the microballoon's membrane.
Genisa-Blätter IV
(2023)
Auch wenn Genisot – jüdische Ablagen nicht mehr verwendeter Bücher und Kultgegenstände – in der bisherigen historischen Forschung selten beachtet werden, sind sie als Quellen aus originär jüdischer Hand von hoher Bedeutung und können unser Verständnis der Umsetzung von Ritualen im Kontext der lokalen Gemeinde vertiefen.
Der Schwerpunkt der ‚Genisa-Blätter IV‘ liegt auf Fragen nach jüdisch-rituellen Praktiken und ihrer Bedeutung, ihren Objekten und Akteuren. Acht wissenschaftliche und ein essayistischer Beitrag nähern sich diesen Themen über konkrete Funde aus Genisot mitteleuropäischer jüdischer Gemeinden, von religiösen Texten wie dem Fragment einer Torarolle und einem Minhagim-Buch über Personaldokumente bis hin zu Musiknoten und Kleidungsstücken.
Background
Maximal isokinetic strength ratios of joint flexors and extensors are important parameters to indicate the level of muscular balance at the joint. Further, in combat sports athletes, upper and lower limb muscle strength is affected by the type of sport. Thus, this study aimed to examine the differences in maximal isokinetic strength of the flexors and extensors and the corresponding flexor–extensor strength ratios of the elbows and knees in combat sports athletes.
Method
Forty male participants (age = 22.3 ± 2.5 years) from four different combat sports (amateur boxing, taekwondo, karate, and judo; n = 10 per sport) were tested for eccentric peak torque of the elbow/knee flexors (EF/KF) and concentric peak torque of the elbow/knee extensors (EE/KE) at three different angular velocities (60, 120, and 180°/s) on the dominant and non-dominant side using an isokinetic device.
Results
Analyses revealed significant, large-sized group × velocity × limb interactions for EF, EE, and EF–EE ratio, KF, KE, and KF–KE ratio (p ≤ 0.03; 0.91 ≤ d ≤ 1.75). Post-hoc analyses indicated that amateur boxers displayed the largest EE strength values on the non-dominant side at ≤ 120°/s and the dominant side at ≥ 120°/s (p < 0.03; 1.21 ≤ d ≤ 1.59). The largest EF–EE strength ratios were observed on amateur boxers’ and judokas’ non-dominant side at ≥ 120°/s (p < 0.04; 1.36 ≤ d ≤ 2.44). Further, we found lower KF–KE strength measures in karate (p < 0.04; 1.12 ≤ d ≤ 6.22) and judo athletes (p ≤ 0.03; 1.60 ≤ d ≤ 5.31) particularly on the non-dominant side.
Conclusions
The present findings indicated combat sport-specific differences in maximal isokinetic strength measures of EF, EE, KF, and KE particularly in favor of amateur boxers on the non-dominant side.
This study examined the spoken narrative skills of a group of bilingual Mandarin–English speaking 3–6-year-olds (N = 25) in Australia, using a remote online story-retell task. Bilingual preschoolers are an understudied population, especially those who are speaking typologically distinct languages such as Mandarin and English which have fewer structural overlaps compared to language pairs that are typologically closer, reducing cross-linguistic positive transfer. We examined these preschoolers’ spoken narrative skills as measured by macrostructures (the global organization of a story) and microstructures (linguistic structures, e.g., total number of utterances, nouns, verbs, phrases, and modifiers) across and within each language, and how various factors such as age and language experiences contribute to individual variability. The results indicate that our bilingual preschoolers acquired spoken narrative skills similarly across their two languages, i.e., showing similar patterns of productivity for macrostructure and microstructure elements in both of their two languages. While chronological age was positively correlated with macrostructures in both languages (showing developmental effects), there were no significant correlations between measures of language experiences and the measures of spoken narrative skills (no effects for language input/output). The findings suggest that although these preschoolers acquire two typologically diverse languages in different learning environments, Mandarin at home with highly educated parents, and English at preschool, they displayed similar levels of oral narrative skills as far as these macro−/micro-structure measures are concerned. This study provides further evidence for the feasibility of remote online assessment of preschoolers’ narrative skills.
Objective: There is a lack of brief rating scales for the reliable assessment of psychotherapeutic skills, which do not require intensive rater training and/or a high level of expertise. Thus, the objective is to validate a 14-item version of the Clinical Communication Skills Scale (CCSS-S).
Methods: Using a sample of N = 690 video-based ratings of role-plays with simulated patients, we calculated a confirmatory factor analysis and an exploratory structural equation modeling (ESEM), assessed convergent validities, determined inter-rater reliabilities and compared these with those who were either psychology students, advanced psychotherapy trainees, or experts.
Results: Correlations with other competence rating scales were high (rs > 0.86–0.89). The intraclass correlations ranged between moderate and good [ICC(2,2) = 0.65–0.80], with student raters yielding the lowest scores. The one-factor model only marginally replicated the data, but the internal consistencies were excellent (α = 0.91–95). The ESEM yielded a two-factor solution (Collaboration and Structuring and Exploration Skills).
Conclusion: The CCSS-S is a brief and valid rating scale that reliably assesses basic communication skills, which is particularly useful for psychotherapy training using standardized role-plays. To ensure good inter-rater reliabilities, it is still advisable to employ raters with at least some clinical experience. Future studies should further investigate the one- or two-factor structure of the instrument.
For life-long learning, an effective learning strategy repertoire is particularly important during acquisition of knowledge in lower secondary school—an educational level characterized with transition into more autonomous learning environments with increased complex academic demands. Using latent profile analysis, we explored the occurrence of different secondary school learner profiles depending on their various combinations of cognitive and metacognitive learning strategy use, as well as their differences in perceived autonomy support, intrinsic motivation, and gender. Data were collected from 576 ninth grade students in Uganda using self-report questionnaires. Four learner profiles were identified: competent strategy user, struggling user, surface-level learner, and deep-level learner profiles. Gender differences were noted in students’ use of elaboration and organization strategies to learn Physics, in favor of girls. In terms of profile memberships, significant differences in gender, intrinsic motivation and perceived autonomy support were also noted. Girls were 2.4–2.7 times more likely than boys to be members of the competent strategy user and surface-level learner profiles. Additionally, higher levels of intrinsic motivation predicted an increased likelihood membership into the deep-level learner profile, while higher levels of perceived teacher autonomy predicted an increased likelihood membership into the competent strategy user profile as compared to other profiles. Further, implications of the findings were discussed.
There is an ongoing debate about how to test and operationalize self-control. This limited understanding is in large part due to a variety of different tests and measures used to assess self-control, as well as the lack of empirical studies examining the temporal dynamics during the exertion of self-control. In order to track changes that occur over the course of exposure to a self-control task, we investigate and compare behavioral, subjective, and physiological indicators during the exertion of self-control. Participants completed both a task requiring inhibitory control (Go/No-Go task) and a control task (two-choice task). Behavioral performance and pupil size were measured during the tasks. Subjective vitality was measured before and after the tasks. While pupil size and subjective vitality showed similar trajectories in the two tasks, behavioral performance decreased in the inhibitory control-demanding task, but not in the control task. However, behavioral, subjective, and physiological measures were not significantly correlated. These results suggest that there is a disconnect between different measures of self-control with high intra- and interindividual variability. Theoretical and methodological implications for self-control theory and future empirical work are discussed.
Background
Communicating a diagnosis is highly important, yet complex, especially in the context of cancer and mental disorders. The aim was to explore the communication style of an oncologist vs. psychotherapist in an online study.
Methods
Patients (N = 136: 65 cancer, 71 depression) were randomly assigned to watch a standardized video vignette with one of two communication styles (empathic vs. unempathic). Outcome measures of affectivity, information recall, communication skills, empathy and trust were applied.
Results
Regardless of diagnosis, empathic communication was associated with the perception of a significantly more empathic (p < 0.001, η2partial = 0.08) and trustworthy practitioner (p = 0.014, η2partial = 0.04) with better communication skills (p = 0.013, η2partial = 0.05). Cancer patients reported a larger decrease in positive affect (p < 0.001, η2partial = 0.15) and a larger increase in negative affect (p < 0.001, η2partial = 0.14) from pre- to post-video than depressive patients. Highly relevant information was recalled better in both groups (p < 0.001, d = 0.61–1.06).
Conclusions
The results highlight the importance of empathy while communicating both a diagnosis of cancer and a mental disorder. Further research should focus on the communication of a mental disorder in association with cancer.
Basic psychological needs theory postulates that a social environment that satisfies individuals’ three basic psychological needs of autonomy, competence, and relatedness leads to optimal growth and well-being. On the other hand, the frustration of these needs is associated with ill-being and depressive symptoms foremost investigated in non-clinical samples; yet, there is a paucity of research on need frustration in clinical samples. Survey data were compared between adult individuals with major depressive disorder (MDD; n = 115; 48.69% female; 38.46 years, SD = 10.46) with those of a non-depressed comparison sample (n = 201; 53.23% female; 30.16 years, SD = 12.81). Need profiles were examined with a linear mixed model (LMM). Individuals with depression reported higher levels of frustration and lower levels of satisfaction in relation to the three basic psychological needs when compared to non-depressed adults. The difference between depressed and non-depressed groups was significantly larger for frustration than satisfaction regarding the needs for relatedness and competence. LMM correlation parameters confirmed the expected positive correlation between the three needs. This is the first study showing substantial differences in need-based experiences between depressed and non-depressed adults. The results confirm basic assumptions of the self-determination theory and have preliminary implications in tailoring therapy for depression.
Dementia as one of the most prevalent diseases urges for a better understanding of the central mechanisms responsible for clinical symptoms, and necessitates improvement of actual diagnostic capabilities. The brainstem nucleus locus coeruleus (LC) is a promising target for early diagnosis because of its early structural alterations and its relationship to the functional disturbances in the patients. In this study, we applied our improved method of localisation-based LC resting-state fMRI to investigate the differences in central sensory signal processing when comparing functional connectivity (fc) of a patient group with mild cognitive impairment (MCI, n = 28) and an age-matched healthy control group (n = 29). MCI and control participants could be differentiated in their Mini-Mental-State-Examination (MMSE) scores (p < .001) and LC intensity ratio (p = .010). In the fMRI, LC fc to anterior cingulate cortex (FDR p < .001) and left anterior insula (FDR p = .012) was elevated, and LC fc to right temporoparietal junction (rTPJ, FDR p = .012) and posterior cingulate cortex (PCC, FDR p = .021) was decreased in the patient group. Importantly, LC to rTPJ connectivity was also positively correlated to MMSE scores in MCI patients (p = .017). Furthermore, we found a hyperactivation of the left-insula salience network in the MCI patients. Our results and our proposed disease model shed new light on the functional pathogenesis of MCI by directing to attentional network disturbances, which could aid new therapeutic strategies and provide a marker for diagnosis and prediction of disease progression.
Privacy regulations and the physical distribution of heterogeneous data are often primary concerns for the development of deep learning models in a medical context. This paper evaluates the feasibility of differentially private federated learning for chest X-ray classification as a defense against data privacy attacks. To the best of our knowledge, we are the first to directly compare the impact of differentially private training on two different neural network architectures, DenseNet121 and ResNet50. Extending the federated learning environments previously analyzed in terms of privacy, we simulated a heterogeneous and imbalanced federated setting by distributing images from the public CheXpert and Mendeley chest X-ray datasets unevenly among 36 clients. Both non-private baseline models achieved an area under the receiver operating characteristic curve (AUC) of 0.940.94 on the binary classification task of detecting the presence of a medical finding. We demonstrate that both model architectures are vulnerable to privacy violation by applying image reconstruction attacks to local model updates from individual clients. The attack was particularly successful during later training stages. To mitigate the risk of a privacy breach, we integrated Rényi differential privacy with a Gaussian noise mechanism into local model training. We evaluate model performance and attack vulnerability for privacy budgets ε∈{1,3,6,10}�∈{1,3,6,10}. The DenseNet121 achieved the best utility-privacy trade-off with an AUC of 0.940.94 for ε=6�=6. Model performance deteriorated slightly for individual clients compared to the non-private baseline. The ResNet50 only reached an AUC of 0.760.76 in the same privacy setting. Its performance was inferior to that of the DenseNet121 for all considered privacy constraints, suggesting that the DenseNet121 architecture is more robust to differentially private training.
In this work, binding interactions between biomolecules were analyzed by a technique that is based on electrically controllable DNA nanolevers. The technique was applied to virus-receptor interactions for the first time. As receptors, primarily peptides on DNA nanostructures and antibodies were utilized. The DNA nanostructures were integrated into the measurement technique and enabled the presentation of the peptides in a controllable geometrical order. The number of peptides could be varied to be compatible to the binding sites of the viral surface proteins.
Influenza A virus served as a model system, on which the general measurability was demonstrated. Variations of the receptor peptide, the surface ligand density, the measurement temperature and the virus subtypes showed the sensitivity and applicability of the technology. Additionally, the immobilization of virus particles enabled the measurement of differences in oligovalent binding of DNA-peptide nanostructures to the viral proteins in their native environment.
When the coronavirus pandemic broke out in 2020, work on binding interactions of a peptide from the hACE2 receptor and the spike protein of the SARS-CoV-2 virus revealed that oligovalent binding can be quantified in the switchSENSE technology. It could also be shown that small changes in the amino acid sequence of the spike protein resulted in complete loss of binding. Interactions of the peptide and inactivated virus material as well as pseudo virus particles could be measured. Additionally, the switchSENSE technology was utilized to rank six antibodies for their binding affinity towards the nucleocapsid protein of SARS-CoV-2 for the development of a rapid antigen test device.
The technique was furthermore employed to show binding of a non-enveloped virus (adenovirus) and a virus-like particle (norovirus-like particle) to antibodies. Apart from binding interactions, the use of DNA origami levers with a length of around 50 nm enabled the switching of virus material. This proved that the technology is also able to size objects with a hydrodynamic diameter larger than 14 nm.
A theoretical work on diffusion and reaction-limited binding interactions revealed that the technique and the chosen parameters enable the determination of binding rate constants in the reaction-limited regime.
Overall, the applicability of the switchSENSE technique to virus-receptor binding interactions could be demonstrated on multiple examples. While there are challenges that remain, the setup enables the determination of affinities between viruses and receptors in their native environment. Especially the possibilities regarding the quantification of oligo- and multivalent binding interactions could be presented.
The central gas in half of all galaxy clusters shows short cooling times. Assuming unimpeded cooling, this should lead to high star formation and mass cooling rates, which are not observed. Instead, it is believed that condensing gas is accreted by the central black hole that powers an active galactic nuclei jet, which heats the cluster. The detailed heating mechanism remains uncertain. A promising mechanism invokes cosmic ray protons that scatter on self-generated magnetic fluctuations, i.e. Alfvén waves. Continuous damping of Alfvén waves provides heat to the intracluster medium. Previous work has found steady state solutions for a large sample of clusters where cooling is balanced by Alfvénic wave heating. To verify modeling assumptions, we set out to study cosmic ray injection in three-dimensional magnetohydrodynamical simulations of jet feedback in an idealized cluster with the moving-mesh code arepo. We analyze the interaction of jet-inflated bubbles with the turbulent magnetized intracluster medium.
Furthermore, jet dynamics and heating are closely linked to the largely unconstrained jet composition. Interactions of electrons with photons of the cosmic microwave background result in observational signatures that depend on the bubble content. Those recent observations provided evidence for underdense bubbles with a relativistic filling while adopting simplifying modeling assumptions for the bubbles. By reproducing the observations with our simulations, we confirm the validity of their modeling assumptions and as such, confirm the important finding of low-(momentum) density jets.
In addition, the velocity and magnetic field structure of the intracluster medium have profound consequences for bubble evolution and heating processes. As velocity and magnetic fields are physically coupled, we demonstrate that numerical simulations can help link and thereby constrain their respective observables. Finally, we implement the currently preferred accretion model, cold accretion, into the moving-mesh code arepo and study feedback by light jets in a radiatively cooling magnetized cluster. While self-regulation is attained independently of accretion model, jet density and feedback efficiencies, we find that in order to reproduce observed cold gas morphology light jets are preferred.
In recent years digital technologies have become a major means for providing health-related services and this trend was strongly reinforced by the current Coronavirus disease 2019 (COVID-19) pandemic. As it is well-known that regular physical activity has positive effects on individual physical and mental health and thus is an important prerequisite for healthy aging, digital technologies are also increasingly used to promote unstructured and structured forms of physical activity. However, in the course of this development, several terms (e.g., Digital Health, Electronic Health, Mobile Health, Telehealth, Telemedicine, and Telerehabilitation) have been introduced to refer to the application of digital technologies to provide health-related services such as physical interventions. Unfortunately, the above-mentioned terms are often used in several different ways, but also relatively interchangeably. Given that ambiguous terminology is a major source of difficulty in scientific communication which can impede the progress of theoretical and empirical research, this article aims to make the reader aware of the subtle differences between the relevant terms which are applied at the intersection of physical activity and Digital Health and to provide state-of-art definitions for them.
Numerical magnitude information is assumed to be spatially represented in the form of a mental number line defined with respect to a body-centred, egocentric frame of reference. In this context, spatial language skills such as mastery of verbal descriptions of spatial position (e.g., in front of, behind, to the right/left) have been proposed to be relevant for grasping spatial relations between numerical magnitudes on the mental number line. We examined 4- to 5-year-old’s spatial language skills in tasks that allow responses in egocentric and allocentric frames of reference, as well as their relative understanding of numerical magnitude (assessed by a number word comparison task). In addition, we evaluated influences of children’s absolute understanding of numerical magnitude assessed by their number word comprehension (montring different numbers using their fingers) and of their knowledge on numerical sequences (determining predecessors and successors as well as identifying missing dice patterns of a series). Results indicated that when considering responses that corresponded to the egocentric perspective, children’s spatial language was associated significantly with their relative numerical magnitude understanding, even after controlling for covariates, such as children’s SES, mental rotation skills, and also absolute magnitude understanding or knowledge on numerical sequences. This suggests that the use of egocentric reference frames in spatial language may facilitate spatial representation of numbers along a mental number line and thus seem important for preschoolers’ relative understanding of numerical magnitude.
In intervention research, single-case experimental designs are an important way to gain insights into the causes of individual changes that yield high internal validity. They are commonly applied to examine the effectiveness of classroom-based interventions to reduce problem behavior in schools. At the same time, there is no consensus on good design characteristics of single-case experimental designs when dealing with behavioral problems in schools. Moreover, specific challenges arise concerning appropriate approaches to analyzing behavioral data. Our study addresses the interplay between the test power of piecewise regression analysis and important design specifications of single-case research designs. Here, we focus on the influence of the following specifications of single-case research designs: number of measurement times, the initial frequency of the behavior, intervention effect, and data trend. We conducted a Monte-Carlo study. First, simulated datasets were created with specific design conditions based on reviews of published single-case intervention studies. Following, data were analyzed using piecewise Poisson-regression models, and the influence of specific design specifications on the test power was investigated. Our results indicate that piecewise regressions have a high potential of adequately identifying the effects of interventions for single-case studies. At the same time, test power is strongly related to the specific design specifications of the single-case study: Few measurement times, especially in phase A, and low initial frequencies of the behavior make it impossible to detect even large intervention effects. Research designs with a high number of measurement times show robust power. The insights gained are highly relevant for researchers in the field, as decisions during the early stage of conceptualizing and planning single-case experimental design studies may impact the chance to identify an existing intervention effect during the research process correctly.
The aim of this review was to describe and summarize the scientific literature on programming parameters related to jump or plyometric training in male and female soccer players of different ages and fitness levels. A literature search was conducted in the electronic databases PubMed, Web of Science and Scopus using keywords related to the main topic of this study (e.g., “ballistic” and “plyometric”). According to the PICOS framework, the population for the review was restricted to soccer players, involved in jump or plyometric training. Among 7556 identified studies, 90 were eligible for inclusion. Only 12 studies were found for females. Most studies (n = 52) were conducted with youth male players. Moreover, only 35 studies determined the effectiveness of a given jump training programming factor. Based on the limited available research, it seems that a dose of 7 weeks (1–2 sessions per week), with ~80 jumps (specific of combined types) per session, using near-maximal or maximal intensity, with adequate recovery between repetitions (<15 s), sets (≥30 s) and sessions (≥24–48 h), using progressive overload and taper strategies, using appropriate surfaces (e.g., grass), and applied in a well-rested state, when combined with other training methods, would increase the outcome of effective and safe plyometric-jump training interventions aimed at improving soccer players physical fitness. In conclusion, jump training is an effective and easy-to-administer training approach for youth, adult, male and female soccer players. However, optimal programming for plyometric-jump training in soccer is yet to be determined in future research.
Quantifying neurological disorders from voice is a rapidly growing field of research and holds promise for unobtrusive and large-scale disorder monitoring. The data recording setup and data analysis pipelines are both crucial aspects to effectively obtain relevant information from participants. Therefore, we performed a systematic review to provide a high-level overview of practices across various neurological disorders and highlight emerging trends. PRISMA-based literature searches were conducted through PubMed, Web of Science, and IEEE Xplore to identify publications in which original (i.e., newly recorded) datasets were collected. Disorders of interest were psychiatric as well as neurodegenerative disorders, such as bipolar disorder, depression, and stress, as well as amyotrophic lateral sclerosis amyotrophic lateral sclerosis, Alzheimer's, and Parkinson's disease, and speech impairments (aphasia, dysarthria, and dysphonia). Of the 43 retrieved studies, Parkinson's disease is represented most prominently with 19 discovered datasets. Free speech and read speech tasks are most commonly used across disorders. Besides popular feature extraction toolkits, many studies utilise custom-built feature sets. Correlations of acoustic features with psychiatric and neurodegenerative disorders are presented. In terms of analysis, statistical analysis for significance of individual features is commonly used, as well as predictive modeling approaches, especially with support vector machines and a small number of artificial neural networks. An emerging trend and recommendation for future studies is to collect data in everyday life to facilitate longitudinal data collection and to capture the behavior of participants more naturally. Another emerging trend is to record additional modalities to voice, which can potentially increase analytical performance.
Facing the environmental crisis, new technologies are needed to sustain our society. In this context, this thesis aims to describe the properties and applications of carbon-based sustainable materials. In particular, it reports the synthesis and characterization of a wide set of porous carbonaceous materials with high nitrogen content obtained from nucleobases. These materials are used as cathodes for Li-ion capacitors, and a major focus is put on the cathode preparation, highlighting the oxidation resistance of nucleobase-derived materials. Furthermore, their catalytic properties for acid/base and redox reactions are described, pointing to the role of nitrogen speciation on their surfaces. Finally, these materials are used as supports for highly dispersed nickel loading, activating the materials for carbon dioxide electroreduction.
Sulfur is an important element that is incorporated into many biomolecules in humans. The incorporation and transfer of sulfur into biomolecules is, however, facilitated by a series of different sulfurtransferases. Among these sulfurtransferases is the human mercaptopyruvate sulfurtransferase (MPST) also designated as tRNA thiouridine modification protein (TUM1). The role of the human TUM1 protein has been suggested in a wide range of physiological processes in the cell among which are but not limited to involvement in Molybdenum cofactor (Moco) biosynthesis, cytosolic tRNA thiolation and generation of H2S as signaling molecule both in mitochondria and the cytosol. Previous interaction studies showed that TUM1 interacts with the L-cysteine desulfurase NFS1 and the Molybdenum cofactor biosynthesis protein 3 (MOCS3). Here, we show the roles of TUM1 in human cells using CRISPR/Cas9 genetically modified Human Embryonic Kidney cells. Here, we show that TUM1 is involved in the sulfur transfer for Molybdenum cofactor synthesis and tRNA thiomodification by spectrophotometric measurement of the activity of sulfite oxidase and liquid chromatography quantification of the level of sulfur-modified tRNA. Further, we show that TUM1 has a role in hydrogen sulfide production and cellular bioenergetics.
Das Dokument "Forschungsdatenmanagement bei personenbezogenen Daten - eine Handreichung" versammelt zentrale Inhalte, Verweise und Vorgehensweisen für Forscher*innen, die in einer Studie personenbezogene Daten erheben und diese verarbeiten, archivieren oder veröffentlichen wollen. Die Handreichung verweist an den entsprechenden Abschnitten auf weiterführende Materialien wie insbesondere die Handreichung „Datenschutz“ des Rats für die Sozial-, Verhaltens-, Bildungs- und Wirtschaftswissenschaften (RatSWD).
In late summer, migratory bats of the temperate zone face the challenge of accomplishing two energy-demanding tasks almost at the same time: migration and mating. Both require information and involve search efforts, such as localizing prey or finding potential mates. In non-migrating bat species, playback studies showed that listening to vocalizations of other bats, both con-and heterospecifics, may help a recipient bat to find foraging patches and mating sites. However, we are still unaware of the degree to which migrating bats depend on con-or heterospecific vocalizations for identifying potential feeding or mating opportunities during nightly transit flights. Here, we investigated the vocal responses of Nathusius’ pipistrelle bats, Pipistrellus nathusii, to simulated feeding and courtship aggregations at a coastal migration corridor. We presented migrating bats either feeding buzzes or courtship calls of their own or a heterospecific migratory species, the common noctule, Nyctalus noctula. We expected that during migratory transit flights, simulated feeding opportunities would be particularly attractive to bats, as well as simulated mating opportunities which may indicate suitable roosts for a stopover. However, we found that when compared to the natural silence of both pre-and post-playback phases, bats called indifferently during the playback of conspecific feeding sounds, whereas P. nathusii echolocation call activity increased during simulated feeding of N. noctula. In contrast, the call activity of P. nathusii decreased during the playback of conspecific courtship calls, while no response could be detected when heterospecific call types were broadcasted. Our results suggest that while on migratory transits, P. nathusii circumnavigate conspecific mating aggregations, possibly to save time or to reduce the risks associated with social interactions where aggression due to territoriality might be expected. This avoidance behavior could be a result of optimization strategies by P. nathusii when performing long-distance migratory flights, and it could also explain the lack of a response to simulated conspecific feeding. However, the observed increase of activity in response to simulated feeding of N. noctula, suggests that P. nathusii individuals may be eavesdropping on other aerial hawking insectivorous species during migration, especially if these occupy a slightly different foraging niche.
Genetic divergence and the frequency of hybridization are central for defining species delimitations, especially among cryptic species where morphological differences are merely absent. Rotifers are known for their high cryptic diversity and therefore are ideal model organisms to investigate such patterns. Here, we used the recently resolved Brachionus calyciflorus species complex to investigate whether previously observed between species differences in thermotolerance and gene expression are also reflected in their genomic footprint. We identified a Heat Shock Protein gene (HSP 40 kDa) which exhibits cross species pronounced sequence variation. This gene exhibits species-specific fixed sites, alleles, and sites putatively under positive selection. These sites are located in protein binding regions involved in chaperoning and may therefore reflect adaptive diversification. By comparing three genetic markers (ITS, COI, HSP 40 kDa), we revealed hybridization events between the cryptic species. The low frequency of introgressive haplotypes/alleles suggest a tight, but not fully impermeable boundary between the cryptic species.
This study examines the access to healthcare for children and adolescents with three common chronic diseases (type-1 diabetes (T1D), obesity, or juvenile idiopathic arthritis (JIA)) within the 4th (Delta), 5th (Omicron), and beginning of the 6th (Omicron) wave (June 2021 until July 2022) of the COVID-19 pandemic in Germany in a cross-sectional study using three national patient registries. A paper-and-pencil questionnaire was given to parents of pediatric patients (<21 years) during the routine check-ups. The questionnaire contains self-constructed items assessing the frequency of healthcare appointments and cancellations, remote healthcare, and satisfaction with healthcare. In total, 905 parents participated in the T1D-sample, 175 in the obesity-sample, and 786 in the JIA-sample. In general, satisfaction with healthcare (scale: 0–10; 10 reflecting the highest satisfaction) was quite high (median values: T1D 10, JIA 10, obesity 8.5). The proportion of children and adolescents with canceled appointments was relatively small (T1D 14.1%, JIA 11.1%, obesity 20%), with a median of 1 missed appointment, respectively. Only a few parents (T1D 8.6%; obesity 13.1%; JIA 5%) reported obstacles regarding health services during the pandemic. To conclude, it seems that access to healthcare was largely preserved for children and adolescents with chronic health conditions during the COVID-19 pandemic in Germany.