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The ongoing climate change is altering the living conditions for many organisms on this planet at an unprecedented pace. Hence, it is crucial for the survival of species to adapt to these changing conditions. In this dissertation Silene vulgaris is used as a model organism to understand the adaption strategies of widely distributed plant species to the current climate change. Especially plant species that possess a wide geographic range are expected to have a high phenotypic plasticity or to show genetic differentiation in response to the different climate conditions they grow in. However, they are often underrepresented in research.
In the greenhouse experiment presented in this thesis, I examined the phenotypic responses and plasticity in S. vulgaris to estimate its’ adaptation potential. Seeds from 25 wild European populations were collected along a latitudinal gradient and grown in a greenhouse under three different precipitation (65 mm, 75 mm, 90 mm) and two different temperature regimes (18°C, 21°C) that resembled a possible climate change scenario for central Europe. Afterwards different biomass and fecundity-related plant traits were measured.
The treatments significantly influenced the plants but did not reveal a latitudinal difference in response to climate treatments for most plant traits. The number of flowers per individual however, showed a stronger plasticity in northern European populations (e.g., Swedish populations) where numbers decreased more drastically with increased temperature and decreased precipitation.
To gain an even deeper understanding of the adaptation of S. vulgaris to climate change it is also important to reveal the underlying phylogeny of the sampled populations. Therefore, I analysed their population genetic structure through whole genome sequencing via ddRAD.
The sequencing revealed three major genetic clusters in the S. vulgaris populations sampled in Europe: one cluster comprised Southern European populations, one cluster Western European populations and another cluster contained central European populations. A following analysis of experimental trait responses among the clusters to the climate-change scenario showed that the genetic clusters significantly differed in biomass-related traits and in the days to flowering. However, half of the traits showed parallel response patterns to the experimental climate-change scenario.
In addition to the potential geographic and genetic adaptation differences to climate change this dissertation also deals with the response differences between the sexes in S. vulgaris. As a gynodioecious species populations of S. vulgaris consist of female and hermaphrodite
individuals and the sexes can differ in their morphological traits which is known as sexual dimorphism. As climate change is becoming an important factor influencing plant morphology it remains unclear if and how different sexes may respond in sexually dimorphic species. To examine this question the sex of each individual plant was determined during the greenhouse experiment and the measured plant traits were analysed accordingly. In general, hermaphrodites had a higher number of flowers but a lower number of leaves than females. With regards to the climate change treatment, I found that hermaphrodites showed a milder negative response to higher temperatures in the number of flowers produced and in specific leaf area (SLA) compared to females.
Synthesis – The significant treatment response in Silene vulgaris, independent of population origin in most traits suggests a high degree of universal phenotypic plasticity. Also, the three European intraspecific genetic lineages detected showed comparable parallel response patterns in half of the traits suggesting considerable phenotypic plasticity. Hence, plasticity might represent a possible adaptation strategy of this widely distributed species during ongoing and future climatic changes. The results on sexual dimorphism show that females and hermaphrodites are differing mainly in their number of flowers and females are affected more strongly by the experimental climate-change scenario. These results provide a solid knowledge basis on the sexual dimorphism in S. vulgaris under climate change, but further research is needed to determine the long-term impact on the breeding system for the species.
In summary this dissertation provides a comprehensive insight into the adaptation mechanisms and consequences of a widely distributed and gynodioecious plant species and leverages our understanding of the impact of anthropogenic climate change on plants.
The aim of this dissertation was to conduct a larger-scale cross-linguistic empirical investigation of similarity-based interference effects in sentence comprehension.
Interference studies can offer valuable insights into the mechanisms that are involved in long-distance dependency completion.
Many studies have investigated similarity-based interference effects, showing that syntactic and semantic information are employed during long-distance dependency formation (e.g., Arnett & Wagers, 2017; Cunnings & Sturt, 2018; Van Dyke, 2007, Van Dyke & Lewis, 2003; Van Dyke & McElree, 2011). Nevertheless, there are some important open questions in the interference literature that are critical to our understanding of the constraints involved in dependency resolution.
The first research question concerns the relative timing of syntactic and semantic interference in online sentence comprehension. Only few interference studies have investigated this question, and, to date, there is not enough data to draw conclusions with regard to their time course (Van Dyke, 2007; Van Dyke & McElree, 2011).
Our first cross-linguistic study explores the relative timing of syntactic and semantic interference in two eye-tracking reading experiments that implement the study design used in Van Dyke (2007). The first experiment tests English sentences. The second, larger-sample experiment investigates the two interference types in German.
Overall, the data suggest that syntactic and semantic interference can arise simultaneously during retrieval.
The second research question concerns a special case of semantic interference: We investigate whether cue-based retrieval interference can be caused by semantically similar items which are not embedded in a syntactic structure.
This second interference study builds on a landmark study by Van Dyke & McElree (2006). The study design used in their study is unique in that it is able to pin down the source of interference as a consequence of cue overload during retrieval, when semantic retrieval cues do not uniquely match the retrieval target. Unlike most other interference studies, this design is able to rule out encoding interference as an alternative explanation. Encoding accounts postulate that it is not cue overload at the retrieval site but the erroneous encoding of similar linguistic items in memory that leads to interference (Lewandowsky et al., 2008; Oberauer & Kliegl, 2006). While Van Dyke & McElree (2006) reported cue-based retrieval interference from sentence-external distractors, the evidence for this effect was weak. A subsequent study did not show interference of this type (Van Dyke et al., 2014). Given these inconclusive findings, further research is necessary to investigate semantic cue-based retrieval interference.
The second study in this dissertation provides a larger-scale cross-linguistic investigation of cue-based retrieval interference from sentence-external items. Three larger-sample eye-tracking studies in English, German, and Russian tested cue-based interference in the online processing of filler-gap dependencies. This study further extends the previous research by investigating interference in each language under varying task demands (Logačev & Vasishth, 2016; Swets et al., 2008).
Overall, we see some very modest support for proactive cue-based retrieval interference in English. Unexpectedly, this was observed only under a low task demand. In German and Russian, there is some evidence against the interference effect. It is possible that interference is attenuated in languages with richer case marking.
In sum, the cross-linguistic experiments on the time course of syntactic and semantic interference from sentence-internal distractors support existing evidence of syntactic and semantic interference during sentence comprehension. Our data further show that both types of interference effects can arise simultaneously. Our cross-linguistic experiments investigating semantic cue-based retrieval interference from sentence-external distractors suggest that this type of interference may arise only in specific linguistic contexts.
Technological progress allows for producing ever more complex predictive models on the basis of increasingly big datasets. For risk management of natural hazards, a multitude of models is needed as basis for decision-making, e.g. in the evaluation of observational data, for the prediction of hazard scenarios, or for statistical estimates of expected damage. The question arises, how modern modelling approaches like machine learning or data-mining can be meaningfully deployed in this thematic field. In addition, with respect to data availability and accessibility, the trend is towards open data. Topic of this thesis is therefore to investigate the possibilities and limitations of machine learning and open geospatial data in the field of flood risk modelling in the broad sense. As this overarching topic is broad in scope, individual relevant aspects are identified and inspected in detail.
A prominent data source in the flood context is satellite-based mapping of inundated areas, for example made openly available by the Copernicus service of the European Union. Great expectations are directed towards these products in scientific literature, both for acute support of relief forces during emergency response action, and for modelling via hydrodynamic models or for damage estimation. Therefore, a focus of this work was set on evaluating these flood masks. From the observation that the quality of these products is insufficient in forested and built-up areas, a procedure for subsequent improvement via machine learning was developed. This procedure is based on a classification algorithm that only requires training data from a particular class to be predicted, in this specific case data of flooded areas, but not of the negative class (dry areas). The application for hurricane Harvey in Houston shows the high potential of this method, which depends on the quality of the initial flood mask.
Next, it is investigated how much the predicted statistical risk from a process-based model chain is dependent on implemented physical process details. Thereby it is demonstrated what a risk study based on established models can deliver. Even for fluvial flooding, such model chains are already quite complex, though, and are hardly available for compound or cascading events comprising torrential rainfall, flash floods, and other processes. In the fourth chapter of this thesis it is therefore tested whether machine learning based on comprehensive damage data can offer a more direct path towards damage modelling, that avoids explicit conception of such a model chain. For that purpose, a state-collected dataset of damaged buildings from the severe El Niño event 2017 in Peru is used. In this context, the possibilities of data-mining for extracting process knowledge are explored as well. It can be shown that various openly available geodata sources contain useful information for flood hazard and damage modelling for complex events, e.g. satellite-based rainfall measurements, topographic and hydrographic information, mapped settlement areas, as well as indicators from spectral data. Further, insights on damaging processes are discovered, which mainly are in line with prior expectations. The maximum intensity of rainfall, for example, acts stronger in cities and steep canyons, while the sum of rain was found more informative in low-lying river catchments and forested areas. Rural areas of Peru exhibited higher vulnerability in the presented study compared to urban areas. However, the general limitations of the methods and the dependence on specific datasets and algorithms also become obvious.
In the overarching discussion, the different methods – process-based modelling, predictive machine learning, and data-mining – are evaluated with respect to the overall research questions. In the case of hazard observation it seems that a focus on novel algorithms makes sense for future research. In the subtopic of hazard modelling, especially for river floods, the improvement of physical models and the integration of process-based and statistical procedures is suggested. For damage modelling the large and representative datasets necessary for the broad application of machine learning are still lacking. Therefore, the improvement of the data basis in the field of damage is currently regarded as more important than the selection of algorithms.
This study explores the identity of the Bene Israel caste from India and its assimilation into Israeli society. The large immigration from India to Israel started in the early 1950s and continued until the early 1970s. Initially, these immigrants struggled hard as they faced many problems such as the language barrier, cultural differences, a new climate, geographical isolation, and racial discrimination. This analysis focuses on the three major aspects of the integration process involving the Bene Israel: economic, socio-cultural and political. The study covers the period from the early fifties to the present.
I will focus on the origin of the Bene Israel, which has evolved after their immigration to Israel; from a Hindu–Muslim lifestyle and customs they integrated into the Jewish life of Israel. Despite its ethnographic nature, this study has theological implications as it is an encounter between Jewish monotheism and Indian polytheism.
All the western scholars who researched the Bene Israel community felt impelled to rely on information received by community members themselves. No written historical evidence recorded Bene Israel culture and origin. Only during the nineteenth century onwards, after the intrusion of western Jewish missionaries, were Jewish books translated into Marathi . Missionary activities among the Bene Israel served as a catalyst for the Bene Israel themselves to investigate their historical past . Haeem Samuel Kehimkar (1830-1908), a Bene Israel teacher, wrote notes on the history of the Bene Israel in India in Marathi in 1897. Brenda Ness wrote in her dissertation:
The results [of the missionary activities] are several works about the community in English and Marathi by Bene-Israel authors which have appeared during the last century. These are, for the most part, not documented; they consist of much theorizing on accepted tradition and tend to be apologetic in nature.
There can be no philosophical explanation or rational justification for an entire community to leave their motherland India, and enter into a process of annihilation of its own free will. I see this as a social and cultural suicide. In craving for a better future in Israel, the Indian Bene Israel community pays an enormously heavy price as a people that are today discarded by the East and disowned by the West: because they chose to become something that they never were and never could be. As it is written, “know where you came from, and where you are going.” A community with an ancient history from a spiritual culture has completely lost its identity and self-esteem.
In concluding this dissertation, I realize the dilemma with which I have confronted the members of the Bene Israel community which I have reviewed after strenuous and constant self-examination. I chose to evolve the diversifications of the younger generations urges towards acceptance, and wish to clarify my intricate analysis of this controversial community. The complexity of living in a Jewish State, where citizens cannot fulfill their basic desires, like matrimony, forced an entire community to conceal their true identity and perjure themselves to blend in, for the sake of national integration. Although scholars accepted their new claims, the skepticism of the rabbinate authorities prevails, and they refuse to marry them to this day, suspecting they are an Indian caste.
Enhanced geothermal systems (EGS) are considered a cornerstone of future sustainable energy production. In such systems, high-pressure fluid injections break the rock to provide pathways for water to circulate in and heat up. This approach inherently induces small seismic events that, in rare cases, are felt or can even cause damage. Controlling and reducing the seismic impact of EGS is crucial for a broader public acceptance. To evaluate the applicability of hydraulic fracturing (HF) in EGS and to improve the understanding of fracturing processes and the hydromechanical relation to induced seismicity, six in-situ, meter-scale HF experiments with different injection schemes were performed under controlled conditions in crystalline rock in a depth of 410 m at the Äspö Hard Rock Laboratory (Sweden).
I developed a semi-automated, full-waveform-based detection, classification, and location workflow to extract and characterize the acoustic emission (AE) activity from the continuous recordings of 11 piezoelectric AE sensors. Based on the resulting catalog of 20,000 AEs, with rupture sizes of cm to dm, I mapped and characterized the fracture growth in great detail. The injection using a novel cyclic injection scheme (HF3) had a lower seismic impact than the conventional injections. HF3 induced fewer AEs with a reduced maximum magnitude and significantly larger b-values, implying a decreased number of large events relative to the number of small ones. Furthermore, HF3 showed an increased fracture complexity with multiple fractures or a fracture network. In contrast, the conventional injections developed single, planar fracture zones (Publication 1).
An independent, complementary approach based on a comparison of modeled and observed tilt exploits transient long-period signals recorded at the horizontal components of two broad-band seismometers a few tens of meters apart from the injections. It validated the efficient creation of hydraulic fractures and verified the AE-based fracture geometries. The innovative joint analysis of AEs and tilt signals revealed different phases of the fracturing process, including the (re-)opening, growth, and aftergrowth of fractures, and provided evidence for the reactivation of a preexisting fault in one of the experiments (Publication 2). A newly developed network-based waveform-similarity analysis applied to the massive AE activity supports the latter finding.
To validate whether the reduction of the seismic impact as observed for the cyclic injection schemes during the Äspö mine-scale experiments is transferable to other scales, I additionally calculated energy budgets for injection experiments from previously conducted laboratory tests and from a field application. Across all three scales, the cyclic injections reduce the seismic impact, as depicted by smaller maximum magnitudes, larger b-values, and decreased injection efficiencies (Publication 3).
Localisation of deformation is a ubiquitous feature in continental rift dynamics and observed across drastically different time and length scales. This thesis comprises one experimental and two numerical modelling studies investigating strain localisation in (1) a ductile shear zone induced by a material heterogeneity and (2) in an active continental rift setting. The studies are related by the fact that the weakening mechanisms on the crystallographic and grain size scale enable bulk rock weakening, which fundamentally enables the formation of shear zones, continental rifts and hence plate tectonics. Aiming to investigate the controlling mechanisms on initiation and evolution of a shear zone, the torsion experiments of the experimental study were conducted in a Patterson type apparatus with strong Carrara marble cylinders with a weak, planar Solnhofen limestone inclusion. Using state-of-the-art numerical modelling software, the torsion experiments were simulated to answer questions regarding localisation procedure like stress distribution or the impact of rheological weakening. 2D numerical models were also employed to integrate geophysical and geological data to explain characteristic tectonic evolution of the Southern and Central Kenya Rift. Key elements of the numerical tools are a randomized initial strain distribution and the usage of strain softening. During the torsion experiments, deformation begins to localise at the limestone inclusion tips in a process zone, which propagates into the marble matrix with increasing deformation until a ductile shear zone is established. Minor indicators for coexisting brittle deformation are found close to the inclusion tip and presumed to slightly facilitate strain localisation besides the dominant ductile deformation processes. The 2D numerical model of the torsion experiment successfully predicts local stress concentration and strain rate amplification ahead of the inclusion in first order agreement with the experimental results. A simple linear parametrization of strain weaking enables high accuracy reproduction of phenomenological aspects of the observed weakening. The torsion experiments suggest that loading conditions do not affect strain localisation during high temperature deformation of multiphase material with high viscosity contrasts. A numerical simulation can provide a way of analysing the process zone evolution virtually and extend the examinable frame. Furthermore, the nested structure and anastomosing shape of an ultramylonite band was mimicked with an additional second softening step. Rheological weakening is necessary to establish a shear zone in a strong matrix around a weak inclusion and for ultramylonite formation.
Such strain weakening laws are also incorporated into the numerical models of the
Southern and Central Kenya Rift that capture the characteristic tectonic evolution. A three-stage early rift evolution is suggested that starts with (1) the accommodation of strain by a single border fault and flexure of the hanging-wall crust, after which (2) faulting in the hanging-wall and the basin centre increases before (3) the early-stage asymmetry is lost and basinward localisation of deformation occurs. Along-strike variability of rifts can be produced by modifying the initial random noise distribution. In summary, the three studies address selected aspects of the broad range of mechanisms and processes that fundamentally enable the deformation of rock and govern the localisation patterns across the scales. In addition to the aforementioned results, the first and second manuscripts combined, demonstrate a procedure to find new or improve on existing numerical formulations for specific rheologies and their dynamic weakening. These formulations are essential in addressing rock deformation from the grain to the global scale. As within the third study of this thesis, where geodynamic controls on the evolution of a rift were examined and acquired by the integration of geological and geophysical data into a numerical model.
The protein fraction, important for coffee cup quality, is modified during post-harvest treatment prior to roasting. Proteins may interact with phenolic compounds, which constitute the major metabolites of coffee, where the processing affects these interactions. This allows the hypothesis that the proteins are denatured and modified via enzymatic and/or redox activation steps. The present study was initiated to encompass changes in the protein fraction. The investigations were limited to major storage protein of green coffee beans. Fourteen Coffea arabica samples from various processing methods and countries were used. Different extraction protocols were compared to maintain the status quo of the protein modification. The extracts contained about 4–8 µg of chlorogenic acid derivatives per mg of extracted protein. High-resolution chromatography with multiple reaction monitoring was used to detect lysine modifications in the coffee protein. Marker peptides were allocated for the storage protein of the coffee beans. Among these, the modified peptides K.FFLANGPQQGGK.E and R.LGGK.T of the α-chain and R.ITTVNSQK.I and K.VFDDEVK.Q of β-chain were detected. Results showed a significant increase (p < 0.05) of modified peptides from wet processed green beans as compared to the dry ones. The present study contributes to a better understanding of the influence of the different processing methods on protein quality and its role in the scope of coffee cup quality and aroma. View Full-Text
The protein fraction, important for coffee cup quality, is modified during post-harvest treatment prior to roasting. Proteins may interact with phenolic compounds, which constitute the major metabolites of coffee, where the processing affects these interactions. This allows the hypothesis that the proteins are denatured and modified via enzymatic and/or redox activation steps. The present study was initiated to encompass changes in the protein fraction. The investigations were limited to major storage protein of green coffee beans. Fourteen Coffea arabica samples from various processing methods and countries were used. Different extraction protocols were compared to maintain the status quo of the protein modification. The extracts contained about 4–8 µg of chlorogenic acid derivatives per mg of extracted protein. High-resolution chromatography with multiple reaction monitoring was used to detect lysine modifications in the coffee protein. Marker peptides were allocated for the storage protein of the coffee beans. Among these, the modified peptides K.FFLANGPQQGGK.E and R.LGGK.T of the α-chain and R.ITTVNSQK.I and K.VFDDEVK.Q of β-chain were detected. Results showed a significant increase (p < 0.05) of modified peptides from wet processed green beans as compared to the dry ones. The present study contributes to a better understanding of the influence of the different processing methods on protein quality and its role in the scope of coffee cup quality and aroma. View Full-Text
Background: In terms of physiological and biomechanical characteristics, over-pronation of the feet has been associated with distinct muscle recruitment patterns and ground reaction forces during running.
Objective: The aim of this study was to evaluate the effects of running on sand vs. stable ground on ground-reaction-forces (GRFs) and electromyographic (EMG) activity of lower limb muscles in individuals with over-pronated feet (OPF) compared with healthy controls.
Methods: Thirty-three OPF individuals and 33 controls ran at preferred speed and in randomized-order over level-ground and sand. A force-plate was embedded in an 18-m runway to collect GRFs. Muscle activities were recorded using an EMG-system. Data were adjusted for surface-related differences in running speed.
Results: Running on sand resulted in lower speed compared with stable ground running (p < 0.001; d = 0.83). Results demonstrated that running on sand produced higher tibialis anterior activity (p = 0.024; d = 0.28). Also, findings indicated larger loading rates (p = 0.004; d = 0.72) and greater vastus medialis (p < 0.001; d = 0.89) and rectus femoris (p = 0.001; d = 0.61) activities in OPF individuals. Controls but not OPF showed significantly lower gluteus-medius activity (p = 0.022; d = 0.63) when running on sand.
Conclusion: Running on sand resulted in lower running speed and higher tibialis anterior activity during the loading phase. This may indicate alterations in neuromuscular demands in the distal part of the lower limbs when running on sand. In OPF individuals, higher loading rates together with greater quadriceps activity may constitute a proximal compensatory mechanism for distal surface instability.
Background: In terms of physiological and biomechanical characteristics, over-pronation of the feet has been associated with distinct muscle recruitment patterns and ground reaction forces during running.
Objective: The aim of this study was to evaluate the effects of running on sand vs. stable ground on ground-reaction-forces (GRFs) and electromyographic (EMG) activity of lower limb muscles in individuals with over-pronated feet (OPF) compared with healthy controls.
Methods: Thirty-three OPF individuals and 33 controls ran at preferred speed and in randomized-order over level-ground and sand. A force-plate was embedded in an 18-m runway to collect GRFs. Muscle activities were recorded using an EMG-system. Data were adjusted for surface-related differences in running speed.
Results: Running on sand resulted in lower speed compared with stable ground running (p < 0.001; d = 0.83). Results demonstrated that running on sand produced higher tibialis anterior activity (p = 0.024; d = 0.28). Also, findings indicated larger loading rates (p = 0.004; d = 0.72) and greater vastus medialis (p < 0.001; d = 0.89) and rectus femoris (p = 0.001; d = 0.61) activities in OPF individuals. Controls but not OPF showed significantly lower gluteus-medius activity (p = 0.022; d = 0.63) when running on sand.
Conclusion: Running on sand resulted in lower running speed and higher tibialis anterior activity during the loading phase. This may indicate alterations in neuromuscular demands in the distal part of the lower limbs when running on sand. In OPF individuals, higher loading rates together with greater quadriceps activity may constitute a proximal compensatory mechanism for distal surface instability.
Politisches Denken
(2022)
Berufswelt
(2022)
Sustainable urban growth
(2022)
This dissertation explores the determinants for sustainable and socially optimalgrowth in a city. Two general equilibrium models establish the base for this evaluation, each adding its puzzle piece to the urban sustainability discourse and examining the role of non-market-based and market-based policies for balanced growth and welfare improvements in different theory settings. Sustainable urban growth either calls for policy actions or a green energy transition. Further, R&D market failures can pose severe challenges to the sustainability of urban growth and the social optimality of decentralized allocation decisions. Still, a careful (holistic) combination of policy instruments can achieve sustainable growth and even be first best.
Scope: Several studies show that excessive lipid intake can cause hepatic steatosis. To investigate lipotoxicity on cellular level, palmitate (PA) is often used to highly increase lipid droplets (LDs). One way to remove LDs is autophagy, while it is controversially discussed if autophagy is also affected by PA. It is aimed to investigate whether PA-induced LD accumulation can impair autophagy and punicalagin, a natural autophagy inducer from pomegranate, can improve it.
Methods and results: To verify the role of autophagy in LD degradation, HepG2 cells are treated with PA and analyzed for LD and perilipin 2 content in presence of autophagy inducer Torin 1 and inhibitor 3-Methyladenine. PA alone seems to initially induce autophagy-related proteins but impairs autophagic-flux in a time-dependent manner, considering 6 and 24 h PA. To examine whether punicalagin can prevent autophagy impairment, cells are cotreated for 24 h with PA and punicalagin. Results show that punicalagin preserves expression of autophagy-related proteins and autophagic flux, while simultaneously decreasing LDs and perilipin 2.
Conclusion: Data provide new insights into the role of PA-induced excessive LD content on autophagy and suggest autophagy-inducing properties of punicalagin, indicating that punicalagin can be a health-beneficial compound for future research on lipotoxicity in liver.
In den vergangenen Jahren hat der im anglo-amerikanischen Rechtsraum wurzelnde Amicus Curiae, wenn auch in unterschiedlicher Ausprägung, Eingang in die Verwaltungsgerichtsbarkeiten in Deutschland und Frankreich gefunden. Dabei erweist sich die französische Verwaltungsgerichtsordnung aus rechtsvergleichender Sicht als progressiv, da das Verfahrensinstrument hier – im Gegensatz zur deutschen Rechtslage – bereits positiv-rechtlich normiert ist. Diese Fortschrittlichkeit hat sich bisher jedoch nicht merklich auf die Drittinterventionspraxis niedergeschlagen, besitzen Amicus Curiae-Stellungnahmen doch in beiden Ländern und über alle verwaltungsgerichtlichen Instanzen hinweg noch immer Seltenheitswert.
Da mithin keine Generalisierungen zur dieser Rechtspraxis erlaubt sind, kann sich eine Analyse der möglichen funktionalen Rolle derartiger Amicus Curiae-Stellungnahmen nur auf theoretische Überlegungen stützen. Danach ist eine Informationsfunktion gegenüber dem Gericht in Bezug auf Tatsachen- und Rechtsfragen klar zu bejahen. Auch dürfte der Verfahrensmechanismus ein zusätzliches – wenngleich nicht demokratisches – Legitimationspotential für gerichtliche Entscheidungen besitzen: Indem dieser gesellschaftliche Teilhabe und damit gleichzeitig die Einbettung verwaltungsgerichtlicher Verfahren in den jeweiligen sozialen Kontext ermöglicht, kann er zur Steigerung der gesellschaftlichen Akzeptanz der zunehmend unter Rechtsfertigungsdruck geratenden Richtermacht beitragen.
Einleitung
(2022)
Young citizens
(2022)
Aim Hospitals noticeably struggle with maintaining hundreds of IT systems and applications in compliance with the latest IT standards and regulations. Thus, hospitals search for efficient opportunities to discover and integrate useful digital health innovations into their existing IT landscapes. In addition, although a multitude of digital innovations from digital health startups enter the market, numerous barriers impede their successful implementation and adoption. Against this background, the aim of this study was to explore typical digital innovation barriers in hospitals, and to assess how a hospital data management platform (HDMP) architecture might help hospitals to extract such innovative capabilities. Subject and methods Based on the concept of organizational ambidexterity (OA), we pursued a qualitative mixed-methods approach. First, we explored and consolidated innovation barriers through a systematic literature review, interviews with 20 startup representatives, and a focus group interview with a hospital IT team and the CEO of an HDMP provider. Finally, we conducted a case-study analysis of 36 digital health startups to explore and conceptualize the potential impact of DI and apply the morphological method to synthesize our findings from a multi-level perspective. Results We first provide a systematic and conceptual overview of typical barriers for digital innovation in hospitals. Hereupon, we explain how an HDMP might enable hospitals to mitigate such barriers and extract value from digital innovations at both individual and organizational level. Conclusion Our results imply that an HDMP can help hospitals to approach organizational ambidexterity through integrating and maintaining hundreds of systems and applications, which allows for a structured and controlled integration of external digital innovations.
The development of novel programmable materials aiming to control friction in real-time holds potential to facilitate innovative lubrication solutions for reducing wear and energy losses. This work describes the integration of light-responsiveness into two lubricating materials, silicon oils and polymer brush surfaces.
The first part focusses on the assessment on 9-anthracene ester-terminated polydimethylsiloxanes (PDMS-A) and, in particular, on the variability of rheological properties and the implications that arise with UV-light as external trigger. The applied rheometer setup contains an UV-transparent quartz-plate, which enables radiation and simultaneous measurement of the dynamic moduli. UV-A radiation (354 nm) triggers the cycloaddition reaction between the terminal functionalities of linear PDMS, resulting in chain extension. The newly-formed anthracene dimers cleave by UV-C radiation (254 nm) or at elevated temperatures (T > 130 °C). The sequential UV-A radiation and thermal reprogramming over three cycles demonstrate high conversions and reproducible programming of rheological properties. In contrast, the photochemical back reaction by UV-C is incomplete and can only partially restore the initial rheological properties. The dynamic moduli increase with each cycle in photochemical programming, presumably resulting from a chain segment re-arrangement as a result of the repeated partial photocleavage and subsequent chain length-dependent dimerization. In addition, long periods of radiation cause photooxidative degradation, which damages photo-responsive functions and consequently reduces the programming range. The absence of oxygen, however, reduces undesired side reactions. Anthracene-functionalized PDMS and native PDMS mix depending on the anthracene ester content and chain length, respectively, and allow fine-tuning of programmable rheological properties. The work shows the influence of mixing conditions during the photoprogramming step on the rheological properties, indicating that material property gradients induced by light attenuation along the beam have to be considered. Accordingly, thin lubricant films are suggested as potential application for light-programmable silicon fluids.
The second part compares strategies for the grafting of spiropyran (SP) containing copolymer brushes from Si wafers and evaluates the light-responsiveness of the surfaces. Pre-experiments on the kinetics of the thermally initiated RAFT copolymerization of 2-hydroxyethyl acrylate (HEA) and spiropyran acrylate (SPA) in solution show, first, a strong retardation by SP and, second, the dependence of SPA polymerization on light. Surprisingly, the copolymerization of SPA is inhibited in the dark. These findings contribute to improve the synthesis of polar, spiropyran-containing copolymers. The comparison between initiator systems for the grafting-from approach indicates PET-RAFT superior to thermally initiated RAFT, suggesting a more efficient initiation of surface-bound CTA by light. Surface-initiated polymerization via PET-RAFT with an initiator system of EosinY (EoY) and ascorbic acid (AscA) facilitates copolymer synthesis from HEA and 5-25 mol% SPA. The resulting polymer film with a thickness of a few nanometers was detected by atomic force microscopy (AFM) and ellipsometry. Water contact angle (CA) measurements demonstrate photo-switchable surface polarity, which is attributed to the photoisomerization between non-polar spiropyran and zwitterionic merocyanine isomer. Furthermore, the obtained spiropyran brushes show potential for further studies on light-programmable properties. In this context, it would be interesting to investigate whether swollen spiropyran-containing polymers change their configuration and thus their film thickness under the influence of light. In addition, further experiments using an AFM or microtribometer should evaluate whether light-programmable solvation enables a change in frictional properties between polymer brush surfaces.
Weather extremes pose a persistent threat to society on multiple layers. Besides an average of ~37,000 deaths per year, climate-related disasters cause destroyed properties and impaired economic activities, eroding people's livelihoods and prosperity. While global temperature rises – caused by anthropogenic greenhouse gas emissions – the direct impacts of climatic extreme events increase and will further intensify without proper adaptation measures. Additionally, weather extremes do not only have local direct effects. Resulting economic repercussions can propagate either upstream or downstream along trade chains causing indirect effects. One approach to analyze these indirect effects within the complex global supply network is the agent-based model Acclimate. Using and extending this loss-propagation model, I focus in this thesis on three aspects of the relation between weather extremes and economic repercussions.
First, extreme weather events cause direct impacts on local economic performance. I compute daily local direct output loss time series of heat stress, river floods, tropical cyclones, and their consecutive occurrence using (near-future) climate projection ensembles. These regional impacts are estimated based on physical drivers and local productivity distribution. Direct effects of the aforementioned disaster categories are widely heterogeneous concerning regional and temporal distribution. As well, their intensity changes differently under future warming. Focusing on the hurricane-impacted capital, I find that long-term growth losses increase with higher heterogeneity of a shock ensemble.
Second, repercussions are sectorally and regionally distributed via economic ripples within the trading network, causing higher-order effects. I use Acclimate to identify three phases of those economic ripples. Furthermore, I compute indirect impacts and analyze overall regional and global production and consumption changes. Regarding heat stress, global consumer losses double while direct output losses increase by a factor 1.5 between 2000 – 2039. In my research I identify the effect of economic ripple resonance and introduce it to climate impact research. This effect occurs if economic ripples of consecutive disasters overlap, which increases economic responses such as an enhancement of consumption losses. These loss enhancements can even be more amplified with increasing direct output losses, e.g. caused by climate crises.
Transport disruptions can cause economic repercussions as well. For this, I extend the model Acclimate with a geographical transportation route and expand the decision horizon of economic agents. Using this, I show that policy-induced sudden trade restrictions (e.g. a no-deal Brexit) can significantly reduce the longer-term economic prosperity of affected regions. Analyses of transportation disruptions in typhoon seasons indicate that severely affected regions must reduce production as demand falls during a storm. Substituting suppliers may compensate for fluctuations at the beginning of the storm, which fails for prolonged disruptions.
Third, possible coping mechanisms and adaptation strategies arise from direct and indirect economic responses to weather extremes. Analyzing annual trade changes due to typhoon-induced transport disruptions depict that overall exports rise. This trade resilience increases with higher network node diversification. Further, my research shows that a basic insurance scheme may diminish hurricane-induced long-term growth losses due to faster reconstruction in disasters aftermaths. I find that insurance coverage could be an economically reasonable coping scheme towards higher losses caused by the climate crisis. Indirect effects within the global economic network from weather extremes indicate further adaptation possibilities. For one, diversifying linkages reduce the hazard of sharp price increases. Next to this, close economic interconnections with regions that do not share the same extreme weather season can be economically beneficial in the medium run. Furthermore, economic ripple resonance effects should be considered while computing costs. Overall, an increase in local adaptation measures reduces economic ripples within the trade network and possible losses elsewhere. In conclusion, adaptation measures are necessary and potential present, but it seems rather not possible to avoid all direct or indirect losses.
As I show in this thesis, dynamical modeling gives valuable insights into how direct and indirect economic impacts arise from different categories of weather extremes. Further, it highlights the importance of resolving individual extremes and reflecting amplifying effects caused by incomplete recovery or consecutive disasters.
The echo chamber model describes the development of groups in heterogeneous social networks. By heterogeneous social network we mean a set of individuals, each of whom represents exactly one opinion. The existing relationships between individuals can then be represented by a graph. The echo chamber model is a time-discrete model which, like a board game, is played in rounds. In each round, an existing relationship is randomly and uniformly selected from the network and the two connected individuals interact. If the opinions of the individuals involved are sufficiently similar, they continue to move closer together in their opinions, whereas in the case of opinions that are too far apart, they break off their relationship and one of the individuals seeks a new relationship. In this paper we examine the building blocks of this model. We start from the observation that changes in the structure of relationships in the network can be described by a system of interacting particles in a more abstract space.
These reflections lead to the definition of a new abstract graph that encompasses all possible relational configurations of the social network. This provides us with the geometric understanding necessary to analyse the dynamic components of the echo chamber model in Part III. As a first step, in Part 7, we leave aside the opinions of the inidividuals and assume that the position of the edges changes with each move as described above, in order to obtain a basic understanding of the underlying dynamics. Using Markov chain theory, we find upper bounds on the speed of convergence of an associated Markov chain to its unique stationary distribution and show that there are mutually identifiable networks that are not apparent in the dynamics under analysis, in the sense that the stationary distribution of the associated Markov chain gives equal weight to these networks.
In the reversible cases, we focus in particular on the explicit form of the stationary distribution as well as on the lower bounds of the Cheeger constant to describe the convergence speed.
The final result of Section 8, based on absorbing Markov chains, shows that in a reduced version of the echo chamber model, a hierarchical structure of the number of conflicting relations can be identified.
We can use this structure to determine an upper bound on the expected absorption time, using a quasi-stationary distribution. This hierarchy of structure also provides a bridge to classical theories of pure death processes. We conclude by showing how future research can exploit this link and by discussing the importance of the results as building blocks for a full theoretical understanding of the echo chamber model. Finally, Part IV presents a published paper on the birth-death process with partial catastrophe. The paper is based on the explicit calculation of the first moment of a catastrophe. This first part is entirely based on an analytical approach to second degree recurrences with linear coefficients. The convergence to 0 of the resulting sequence as well as the speed of convergence are proved. On the other hand, the determination of the upper bounds of the expected value of the population size as well as its variance and the difference between the determined upper bound and the actual value of the expected value. For these results we use almost exclusively the theory of ordinary nonlinear differential equations.
Aufgrund der hohen Konzentration von Bevölkerung, ökonomischen Werten und Infrastrukturen können Städte stark von extremen Wetterereignissen getroffen werden. Insbesondere Hitzewellen und Überflutungen in Folge von Starkregen verursachen in Städten immense gesundheitliche und finanzielle Schäden. Um Schäden zu verringern oder gar zu vermeiden, ist es notwendig, entsprechende Vorsorge- und Klimaanpassungsmaßnahmen zu implementieren.
Im Projekt „Urbane Resilienz gegenüber extremen Wetterereignissen – Typologien und Transfer von Anpassungsstrategien in kleinen Großstädten und Mittelstädten” (ExTrass) lag der Fokus auf den beiden extremen Wetterereignissen Hitze und Starkregen sowie auf kleineren Großstädten (100.000 bis 500.000 Einwohner:innen) und kreisfreien Mittelstädten mit mehr als 50.000 Einwohner:innen. Im Projekt wurde die Stärkung der Klimaresilienz als Verbesserung der Fähigkeiten von Städten, aus vergangenen Ereignissen zu lernen sowie sich an antizipierte Gefahren anzupassen, verstanden. Klimaanpassung wurde demnach als ein Prozess aufgefasst, der durch die Umsetzung von potenziell schadensreduzierenden Maßnahmen beschreib- und operationalisierbar wird.
Das Projekt hatte zwei Ziele: Erstens sollte die Klimaresilienz in den drei Fallstudienstädten Potsdam, Remscheid und Würzburg messbar gestärkt werden. Zweitens sollten Transferpotenziale zwischen Groß- und Mittelstädten in Deutschland identifiziert und besser nutzbar gemacht werden, damit die Wirkung von Pilotvorhaben über die direkt involvierten Städte hinausgehen kann. Im Projekt standen folgende vier Leitfragen im Fokus:
• Wie verbreitet sind Klimaanpassungsaktivitäten in Großstädten und größeren kreisfreien Mittelstädten in Deutschland?
• Welche hemmenden und begünstigenden Faktoren beeinflussen die Klimaanpassung?
• Welche Maßnahmen der Klimaanpassung werden tatsächlich umgesetzt, und wie kann die Umsetzung verbessert werden? Was behindert?
• Inwiefern lassen sich Beispiele guter Praxis auf andere Städte übertragen, adaptieren oder weiterentwickeln?
Die Hauptergebnisse zu diesen Fragestellungen sind im vorliegenden Bericht zusammengefasst.
Diese eher ungewöhnliche, aber sehr persönlich gehaltene Festschrift ist dem langjährigen Wirken von Dr. Christiane Büchner als „Geschäftsführerin“ am Kommunalwissenschaftlichen Institut (KWI) der Universität Potsdam gewidmet. Die von Prof. Jochen Franzke zusammengestellte und herausgegebene Publikation enthält im ersten Teil neben dem Grußwort des Geschäftsführenden Direktors des KWI Herrn Prof. Thorsten Ingo Schmidt eine Reihe persönlicher Würdigungen von Kolleginnen und Kollegen, Gastwissenschaftlern und Mitarbeitenden, die seit 1994 in verschiedenen Phasen der Entwicklung des KWIs mit Dr. Christiane Büchner eng zusammengearbeitet haben. Der abschließende Dokumentationsteil der Publikation enthält neben Auszügen aus dem Schriftenverzeichnis von Dr. Christiane Büchner auch zwei Nachdrucke aus deren Feder zum Thema der Kreisgebietsreform in Brandenburg (von 2001) sowie über den Landkreis Barnim (von 2019).
Das Ziel dieser Arbeit ist die Entwicklung eines Industrie 4.0 Reifegradindex für produzierende Unternehmen (KMU und Mittelstand) mit diskreter Produktion. Die Motivation zu dieser Arbeit entstand aus dem Zögern vieler Unternehmen – insbesondere KMU und Mittelstand – bei der Transformation in Richtung Industrie 4.0. Im Rahmen einer Marktstudie konnte belegt werden, dass 86 Prozent der befragten produzierenden Unternehmen kein für ihr Unternehmen geeignetes Industrie 4.0 Reifegradmodell gefunden haben, mit dem sie ihren Status Quo bewerten und Maßnahmen für einen höheren Grad der Reife ableiten könnten. Die Bewertung bestehender Reifegradmodelle zeigte Defizite hinsichtlich der Industrie 4.0 Abdeckung, der Betrachtung der sozio-technischen Dimensionen Mensch, Technik und Organisation sowie der Betrachtung von Management und Unternehmenskultur. Basierend auf den aktuellen Industrie 4.0 Technologien und Handlungsbereichen wurde ein neues, modular aufgebautes Industrie 4.0 Reifegradmodell entwickelt, das auf einer ganzheitlichen Betrachtung aller sozio-technischen Dimensionen Mensch, Technik und Organisation sowie deren Schnittstellen basiert. Das Modell ermittelt neben dem Overall Industry 4.0 Maturity Index (OI4MI) vier weitere Indizes zur Bewertung der Industrie 4.0 Reife des Unternehmens. Das Modell wurde bei einem Unternehmen validiert und steht nun als Template für darauf aufbauende Forschungsarbeiten zur Verfügung.
Die vorliegende Dissertation verfolgt das Ziel, die diagnostischen Möglichkeiten für das Stö-rungsbild der erworbenen Dyslexie bei deutschsprachigen Personen mit Dyslexie (PmD) zu erweitern und zu spezifizieren.
In der Literatur werden verschiedene Sprachverarbeitungsmodelle diskutiert, die den kognitiven Prozess der Schriftsprachverarbeitung zu erklären versuchen. Alle Überlegungen, Erhebungen und Analysen dieser Dissertation fußen auf den theoretischen Annahmen des kognitiven Zwei-Routen-Lesemodells, welches zwischen lexikalisch-semantischer und segmentaler, sub-lexikalischer Verarbeitung beim Lesen unterscheidet und so die voneinander unabhängigen Fähigkeiten zum Lesen bekannter und unbekannter Wörter abbilden kann. Mit dem im Rahmen der Dissertation entwickelten, kognitiv orientierten Diagnostikverfahren DYMO (Dyslexie Mo-dellorientiert) soll durch die Erhebung der Lesefähigkeiten von PmD eine möglichst genaue modelltheoretische Verortung der Lesebeeinträchtigung erreicht und eine Grundlage für die Planung einer lesebezogenen Therapie geschaffen werden. Dabei werden auch Modellkomponenten des Zwei-Routen-Lesemodells berücksichtigt, die bisher im deutschsprachigen Raum noch nicht etabliert sind. Dazu zählen Unterkomponenten der Visuellen Analyse, die für die Identifikation von Buchstaben und das Kodieren von Buchstabenpositionen verantwortlich sind und Unterkomponenten der segmentalen Leseroute, die den einzelheitlichen Leseprozess auf dieser Modellroute schrittweise abbilden. Das Itemmaterial aus DYMO ist nach diversen psycholinguistisch kontrollierten Variablen kontrolliert. Hierbei werden auch Variablen berücksichtigt, die bisher in der Dyslexiediagnostik für deutschsprachige PmD nicht systematisch erfasst werden können, wie die Wortlänge und die graphematische Komplexität von Pseudowörtern.
Die erste dieser Dissertation zugrundeliegende Publikation (Originalarbeit I) befasst sich mit den Parametern und Modellkomponenten, die für eine umfassende modelltheoretisch basierte Di-agnostik bei erworbener Dyslexie entscheidend sind. Es werden außerdem Überlegungen zu Fehlertypen-Kategorisierung angestellt.
Die zweite Publikation (Originalarbeit II) stellt das Testverfahren DYMO dar. Das dazugehörige Handbuch liefert detaillierte Informationen zum Aufbau und der Konstruktion des Testverfah-rens, zur Durchführung und Auswertung der einzelnen Untertests und zur Einstufung einer Leistung in einen Leistungsbereich. Anhand von ausführlich beschriebenen Fallbeispielen zweier PmD werden die Durchführung, Auswertung, Interpretation und das Ableiten von Therapiezielen dargestellt. Die Ergebnisse dieser Fallbeschreibungen verdeutlichen die diagnostische Ergänzung durch DYMO und zeigen, dass das explizite Untersuchen der Unterkomponenten der Visuellen Analyse und der segmentalen Leseroute sowie der Einbezug der Variablen Wortlänge und gra-phematische Komplexität den Lesebefund spezifizieren und den Therapieeinstieg konkretisieren können.
Die dritte Publikation (Originalarbeit III) zeigt in einer systematischen Vergleichsstudie anhand einer Fallserie von zwölf PmD die Unterschiede zwischen dem Diagnostikverfahren DYMO und einem weiteren kognitiv basierten Diagnostikverfahren. Es wird diskutiert, inwieweit DYMO eine sinnvolle Ergänzung im Diagnostikprozess erworbener Dyslexien darstellen kann. Außerdem werden leicht und schwer beeinträchtigte PmD in Gruppenanalysen verglichen, um zu prüfen, ob DYMO insbesondere bei leicht beeinträchtigten PmD eine Ergänzung bieten kann. Aufgrund des komplexeren Itemmaterials von DYMO (beispielsweise aufgrund der Kontrolle der Wortlänge) wurde angenommen, dass leicht beeinträchtigte PmD in DYMO-Untertests auffälligere Leseleistungen zeigen als in Aufgaben des gegenübergestellten anderen Diagnostikverfahrens. Diese Hypothese konnte teilweise bestätigt werden. Leicht beeinträchtigte PmD zeigten häufiger Längeneffekte als schwer beeinträchtigte PmD. Insgesamt fiel der Gruppenunterschied jedoch nicht so deutlich aus, wie erwartet.
Mit dem kriteriumsorientiert normierten und finalisierten Material von DYMO wurden 17 PmD getestet. Ausführliche Befunde für jede einzelne PmD mit darauffolgenden Therapieimplikationen zeigen, dass insbesondere die Spezifizierung eines segmentalen Lesedefizits bei einer schwer beeinträchtigten Leistung im Lesen von Pseudowörtern zur erweiterten Aussage bezüglich des modelltheoretischen Störungsortes beitragen kann. Dies verdeutlicht die hohe Aussagekraft der DYMO-Untertests und die Relevanz einer spezifischen und detaillierten modellbasierten Befunderhebung für eine explizite, individuelle Therapieplanung bei erworbenen Dyslexien.
Proteine erfüllen bei einer Vielzahl von Prozessen eine essenzielle Rolle. Um diese Funktionsweisen zu verstehen, bedarf es der Aufklärung derer Struktur und deren Bindungsverhaltens mit anderen Molekülen wie Proteinen, Peptiden, Kohlenhydraten oder kleinen Molekülen. Im ersten Teil dieser Arbeit wurden der Wildtyp und die Punktmutante N126W eines Kohlenhydrat-bindenden Proteins aus dem hitzestabilen Bakterium C. thermocellum untersucht, welches Teil eines Komplexes ist, der Kohlenhydrate wie Cellulose erkennen, binden und abbauen kann. Dazu wurde dieses Protein mit E.coli Bakterien hergestellt und durch Metallchelat- und Größenausschlusschromatographie gereinigt. Die Proteine konnten isotopenmarkiert mittels Kernspinresonanz-Spektroskopie (NMR) untersucht werden. H/D-Austauschexperimente zeigten leicht und schwer zugängliche Stellen im Protein für eine mögliche Ligandenwechselwirkung. Anschließend konnte eine Interaktion beider Proteine mit Cellulosefragmenten festgestellt werden. Diese interagieren über zwischenmolekulare Kräfte mit den Seitenketten von aromatischen Aminosäuren und über Wasserstoffbrückenbindungen mit anderen Resten. Weiterhin wurde die Calcium-Bindestelle analysiert und es konnte gezeigt werden, das diese nach der Proteinherstellung mit einem Calcium-Ion besetzt ist und dieses mit dem Komplexbildner EDTA entfernbar ist, jedoch wieder reversibel besetzt werden kann. Zum Schluss wurde mittels zweier Methoden versucht (grafting from und grafting to), das Protein mit einem temperatursensorischen Polymer (Poly-N-Isopropylacrylamid) zu koppeln, um so Eigenschaften wie Löslichkeit oder Stabilität zu beeinflussen. Es zeigte sich, das während die grafting from Methode (Polymer wächst direkt vom Protein) zu einer teilweisen Entfaltung und Destabilisierung des Proteins führte, bei der grafting to Methode (Polymer wird separat hergestellt und dann an das Protein gekoppelt) das Protein seine Stabilität behielt und nur wenige Polymerketten angebaut waren. Der zweite Teil dieser Arbeit beschäftigte sich mit der Interaktion von zwei LIM-Domänen des Proteins Paxillin und der zytoplasmatischen Domäne der Peptide Integrin-β1 und Integrin-β3. Diese spielen eine wichtige Rolle bei der Bewegung von Zellen. Dabei interagieren sie mit einer Vielzahl an anderen Proteinen, um fokale Adhäsionen (Multiproteinkomplexe) zu bilden. Bei der Herstellung des Peptids Integrin-β3 zeigte sich durch Größenausschlusschromatographie und Massenspektrometrie ein Abbau, bei dem verschiedene Aminosäuregruppen abgespalten werden. Dieser konnte durch eine Zugabe des Serinprotease-Inhibitors AEBSF verhindert werden. Anschließend wurde die direkte Interaktion der Proteine untereinander mittels NMR untersucht. Dabei zeigte sich, das Integrin-β1 und Integrin-β3 an die gleiche Position binden, nämlich an den flexiblen Loop der LIM3-Domäne von Paxillin. Die Dissoziationskonstanten zeigten, dass Integrin-β1 mit einer zirka zehnfach höheren Affinität im Vergleich zu Integrin-β3 an Paxillin bindet. Während Paxillins Bindestelle an Integrin-β1 in der Mitte des Peptids liegt, ist bei Integrin-β3 der C-Terminus essenziell. Daher wurden die drei C-terminalen Aminosäuren entfernt und erneut Bindungsstudien durchgeführt, welche gezeigt haben, das die Affinität dadurch fast vollständig unterbunden wurde. Final wurde der flexible Loop der LIM3-Domäne in zwei andere Aminosäuresequenzen mutiert, um die Bindung auf der Paxillin-Seite auszulöschen. Jedoch zeigten sowohl Zirkulardichroismus-Spektroskopie als auch NMR-Spektroskopie, dass die Mutationen zu einer teilweisen Entfaltung der Domäne geführt haben und somit nicht als geeignete Kandidaten für diese Studien identifiziert werden konnten.
Growth differentiation factor 15 (GDF15) is a stress-induced cytokine secreted into the circulation by a number of tissues under different pathological conditions such as cardiovascular disease, cancer or mitochondrial dysfunction, among others. While GDF15 signaling through its recently identified hindbrain-specific receptor GDNF family receptor alpha-like (GFRAL) has been proposed to be involved in the metabolic stress response, its endocrine role under chronic stress conditions is still poorly understood. Mitochondrial dysfunction is characterized by the impairment of oxidative phosphorylation (OXPHOS), leading to inefficient functioning of mitochondria and consequently, to mitochondrial stress. Importantly, mitochondrial dysfunction is among the pathologies to most robustly induce GDF15 as a cytokine in the circulation.
The overall aim of this thesis was to elucidate the role of the GDF15-GFRAL pathway under mitochondrial stress conditions. For this purpose, a mouse model of skeletal muscle-specific mitochondrial stress achieved by ectopic expression of uncoupling protein 1 (UCP1), the HSA-Ucp1-transgenic (TG) mouse, was employed. As a consequence of mitochondrial stress, TG mice display a metabolic remodeling consisting of a lean phenotype, an improved glucose metabolism, an increased metabolic flexibility and a metabolic activation of white adipose tissue.
Making use of TG mice crossed with whole body Gdf15-knockout (GdKO) and Gfral-knockout (GfKO) mouse models, this thesis demonstrates that skeletal muscle mitochondrial stress induces the integrated stress response (ISR) and GDF15 in skeletal muscle, which is released into the circulation as a myokine (muscle-induced cytokine) in a circadian manner. Further, this work identifies GDF15-GFRAL signaling to be responsible for the systemic metabolic remodeling elicited by mitochondrial stress in TG mice. Moreover, this study reveals a daytime-restricted anorexia induced by the GDF15-GFRAL axis under muscle mitochondrial stress, which is, mechanistically, mediated through the induction of hypothalamic corticotropin releasing hormone (CRH). Finally, this work elucidates a so far unknown physiological outcome of the GDF15-GFRAL pathway: the induction of anxiety-like behavior.
In conclusion, this study uncovers a muscle-brain crosstalk under skeletal muscle mitochondrial stress conditions through the induction of GDF15 as a myokine that signals through the hindbrain-specific GFRAL receptor to elicit a stress response leading to metabolic remodeling and modulation of ingestive- and anxiety-like behavior.
Für projektorientierten Unterricht im Schulfach Wirtschaft, Arbeit, Technik ist die Auswahl an praxisorientierten Materialien übersichtlich. Umso erfreulicher ist es, dass Frau Sonja Halboth und Herr Tobias Hoffmann mit Schüler*innen ein Lichtmorsegerät im Rahmen projektorientierten Unterrichts angefertigt haben. Die vorliegende Arbeit gibt sowohl einen guten Überblick in die Möglichkeiten projektorientierten Unterrichts und dessen Bewertung als auch eine Menge praktischer Tipps & Materialien, um projektorientierten Unterricht durchzuführen.
Portal = Diversity
(2022)
In Europa herrscht Krieg, an unserer Universität diskutieren wir über Diversity. Passt das zusammen? Wir denken: ja. Fragen nach Gleichstellung, Diskriminierung und gesellschaftlicher Vielfalt sind irgendwie ständig präsent und doch scheint anderes immer wichtiger zu sein. Wenn wir aber darüber sprechen, wie Menschen unabhängig von ihrer Nationalität, ihrem Alter oder Geschlecht, ihrer Weltanschauung und Religion, ihrer sexuellen Orientierung, ihrem gesundheitlichen, ethnischen und sozialen Hintergrund, gleichberechtigt und ohne Hürden teilhaben können, sind wir mit Grundsatzfragen konfrontiert. Und zugleich mit dem Ursprung von (gewaltvollen) Konflikten überall auf der Welt. Es handelt sich um ein Kernthema des demokratischen Zusammenlebens, nicht nur in Europa. Dabei geht es nicht zuletzt um das zutiefst Persönliche, um Fragen der Identität – doch das Private ist immer auch politisch.
Wie „schwarz“ ist eigentlich mein Seminarplan? Warum lerne ich im Studium der Literaturgeschichte so viel über Schiller und Goethe und so wenig über Bettina von Arnim oder Charlotte von Stein? Weshalb bin ich der einzige Doktorand im Kolloquium, dessen Eltern kein Abitur haben? Wieso finde ich viele Informationen an der Uni nur auf Deutsch? Wo ist der Fahrstuhl, der mich zum Hörsaal bringt? Spricht die jüngere Generation eine Sprache, die ich nicht mehr verstehe?
All diese Fragen zeigen auch, dass sich unsere Gesellschaft wandelt. Das, was früher als „normal“ galt, ist es heute nicht mehr – und eine Hochschule muss dem Rechnung tragen: in Lehre und Forschung, in der Studierendenbetreuung und als Arbeitgeberin. Und tatsächlich machen sich an der Universität Potsdam bereits viele Menschen über solche und ähnliche Fragen Gedanken. Das zeigt die große Vielfalt an Projekten, Forschungsthemen und Lehrveranstaltungen zu Diversität, mit denen sich Studierende und Beschäftigte befassen – meist aus eigener Initiative. Und mit dem Diversity Audit, das die Hochschule derzeit durchläuft, könnte sie dem Ziel einer diversitätssensiblen und diskriminierungsfreien Einrichtung ein Stück näherkommen. Nicht zuletzt ist das Audit die Chance, dass Gleichstellung Teil der Marke „Uni Potsdam“ wird.
Wie immer bieten wir Ihnen über das Titelthema hinaus Einblicke in das, was Forschende, Studierende und Beschäftigte umtreibt: wie sie mit Astronauten über das Leben in einer Weltraumstation ins Gespräch kommen, die Haut von Buckelwalen untersuchen, um deren unsichtbare Bewohner besser kennenzulernen, die elitäre Literaturszene in Berlin-Brandenburg aufmischen oder sich für bessere Arbeitsbedingungen an der Hochschule ins Zeug legen.
Nun noch ein Hinweis: Uns beschäftigt alle sehr, wie der Krieg in der Ukraine ein schnelles Ende finden kann. In Interviews versuchen wir mit Forschenden der Uni Potsdam eine Antwort auf diese Frage zu finden. In diesem Heft beschreibt der Slavist Prof. Dr. Alexander Wöll den Kampf der ukrainischen Bevölkerung um ihre Unabhängigkeit. Außerdem stellen wir Ihnen die Denkfabrik „Translating Eastern Europe“ vor, die an der Universität entstehen soll. Weitere Interviews finden sich auf den Seiten des Referats für Presse- und Öffentlichkeitsarbeit.
Wir wünschen Ihnen eine anregende Lektüre und neue Perspektiven.
In this thesis, the dependencies of charge localization and itinerance in two classes of aromatic molecules are accessed: pyridones and porphyrins. The focus lies on the effects of isomerism, complexation, solvation, and optical excitation, which are concomitant with different crucial biological applications of specific members of these groups of compounds. Several porphyrins play key roles in the metabolism of plants and animals. The nucleobases, which store the genetic information in the DNA and RNA are pyridone derivatives. Additionally, a number of vitamins are based on these two groups of substances.
This thesis aims to answer the question of how the electronic structure of these classes of molecules is modified, enabling the versatile natural functionality. The resulting insights into the effect of constitutional and external factors are expected to facilitate the design of new processes for medicine, light-harvesting, catalysis, and environmental remediation.
The common denominator of pyridones and porphyrins is their aromatic character. As aromaticity was an early-on topic in chemical physics, the overview of relevant theoretical models in this work also mirrors the development of this scientific field in the 20th century. The spectroscopic investigation of these compounds has long been centered on their global, optical transition between frontier orbitals.
The utilization and advancement of X-ray spectroscopic methods characterizing the local electronic structure of molecular samples form the core of this thesis. The element selectivity of the near-edge X-ray absorption fine structure (NEXAFS) is employed to probe the unoccupied density of states at the nitrogen site, which is key for the chemical reactivity of pyridones and porphyrins. The results contribute to the growing database of NEXAFS features and their interpretation, e.g., by advancing the debate on the porphyrin N K-edge through systematic experimental and theoretical arguments. Further, a state-of-the-art laser pump – NEXAFS probe scheme is used to characterize the relaxation pathway of a photoexcited porphyrin on the atomic level.
Resonant inelastic X-ray scattering (RIXS) provides complementary results by accessing the highest occupied valence levels including symmetry information. It is shown that RIXS is an effective experimental tool to gain detailed information on charge densities of individual species in tautomeric mixtures. Additionally, the hRIXS and METRIXS high-resolution RIXS spectrometers, which have been in part commissioned in the course of this thesis, will gain access to the ultra-fast and thermal chemistry of pyridones, porphyrins, and many other compounds.
With respect to both classes of bio-inspired aromatic molecules, this thesis establishes that even though pyridones and porphyrins differ largely by their optical absorption bands and hydrogen bonding abilities, they all share a global stabilization of local constitutional changes and relevant external perturbation. It is because of this wide-ranging response that pyridones and porphyrins can be applied in a manifold of biological and technical processes.
Latein für Jurastudierende
(2022)
Successful communication is often explored by people throughout their life courses. To effectively transfer one’s own information to others, people employ various linguistic tools, such as word order information, prosodic cues, and lexical choices. The exploration of these linguistic cues is known as the study of information structure (IS). Moreover, an important issue in the language acquisition of children is the investigation of how they acquire IS. This thesis seeks to improve our understanding of how children acquire different tools (i.e., prosodical cues, syntactical cues, and the focus particle only) of focus marking in a cross linguistic perspective.
In the first study, following Szendrői and her colleagues (2017)- the sentence-picture verification task- was performed to investigate whether three- to five-year-old Mandarin-speaking children as well as Mandarin-speaking adults could apply prosodic information to recognize focus in sentences. More, in the second study, not only Mandarin-speaking adults and Mandarin-speaking children but also German-speaking adults and German-speaking children were included to confirm the assumption that children could have adult-like performance in understanding sentence focus by identifying language specific cues in their mother tongue from early onwards. In this study, the same paradigm- the sentence-picture verification task- as in the first study was employed together with the eye-tracking method. Finally, in the last study, an issue of whether five-year-old Mandarin-speaking children could understand the pre-subject only sentence was carried out and again whether prosodic information would help them to better understand this kind of sentences.
The overall results seem to suggest that Mandarin-speaking children from early onwards could make use of the specific linguistic cues in their ambient language. That is, in Mandarin, a Topic-prominent and tone language, the word order information plays a more important rule than the prosodic information and even three-year-old Mandarin-speaking children could follow the word order information. More, although it seems that German-speaking children could follow the prosodic information, they did not have the adult-like performance in the object-accented condition. A feasible reason for this result is that there are more possibilities of marking focus in German, such as flexible word order, prosodic information, focus particles, and thus it would take longer time for German-speaking children to manage these linguistic tools. Another important empirical finding regarding the syntactically-marked focus in German is that it seems that the cleft construction is not a valid focus construction and this result corroborates with the previous observations (Dufter, 2009). Further, eye-tracking method did help to uncover how the parser direct their attention for recognizing focus. In the final study, it is showed that with explicit verbal context Mandarin-speaking children could understand the pre-subject only sentence and the study brought a better understanding of the acquisition of the focus particle- only with the Mandarin-speaking children.
Während das nationale und das europäische Wettbewerbsrecht seit vielen Jahrzehnten eine differenzierte Regelung und wissenschaftliche Durchdringung erfahren haben, ist ein vergleichbarer wettbewerbsrechtlicher Normenbestand auf internationaler Ebene nicht zu verzeichnen. Diese Dissertation greift diese Forschungslücke auf und plädiert für die Schaffung eines internationalen, multilateralen Wettbewerbsrechts. Dabei wird der Bestand an hard-law und soft-law untersucht und als Ergebnis gefordert, neue multilaterale Wettbewerbsregelungen zu entwerfen. In institutioneller Hinsicht ist zu fragen, innerhalb welcher internationaler Organisation dies sinnvoll erfolgen kann. Insgesamt unternimmt die Dissertation den Versuch, mögliche Konturen einer globalen Wettbewerbsrechtsordnung aufzuzeigen und vertieft zu begründen.
Das vergessene Gedenken
(2022)
Seit Aufstellung der Bundeswehr 1955 verloren über 3300 Soldaten und Soldatinnen ihr Leben im Dienst. Nur eine kleine Minderheit von ihnen fiel während des Kampfeinsatzes in Afghanistan. Die weitaus meisten Soldaten starben bei Unfällen. Ihnen hat die Bundeswehr lange das öffentliche Gedenken verweigert.
Erst mit Beginn des Afghanistan-Einsatzes 2002 setzte letztlich ein Umdenken ein, das in der Einweihung des Berliner Ehrenmales der Bundeswehr 2009 seinen vorläufigen Höhepunkt findet. Seitdem gedenkt die Bundeswehr offiziell und öffentlich ihrer toten Soldaten.
Aber warum verweigerte die Bundeswehr ihren Toten so lange ein öffentlich sichtbares und dauerhaftes Gedenken?
Julia Katharina Nordmann beleuchtet die komplexen Ursachen für diesen Umgang der Bundeswehr mit ihren Toten. Und sie rekonstruiert den langen und mühsamen Prozess, der zur Ausbildung einer Gedenkkultur geführt hat. Einer Gedenkkultur, die heute in vielfältiger Weise die Toten der Bundeswehr würdigt.
Humankind and their environment need to be protected from the harmful effects of spent nuclear fuel, and therefore disposal in deep geological formations is favoured worldwide. Suitability of potential host rocks is evaluated, among others, by the retention capacity with respect to radionuclides. Safety assessments are based on the quantification of radionuclide migration lengths with numerical simulations as experiments cannot cover the required temporal (1 Ma) and spatial scales (>100 m).
Aim of the present thesis is to assess the migration of uranium, a geochemically complex radionuclide, in the potential host rock Opalinus Clay. Radionuclide migration in clay formations is governed by diffusion due to their low permeability and retarded by sorption. Both processes highly depend on pore water geochemistry and mineralogy that vary between different facies. Diffusion is quantified with the single-component (SC) approach using one diffusion coefficient for all species and the process-based multi-component (MC) option. With this, each species is assigned its own diffusion coefficient and the interaction with the diffuse double layer is taken into account. Sorption is integrated via a bottom-up approach using mechanistic surface complexation models and cation exchange. Therefore, reactive transport simulations are conducted with the geochemical code PHREEQC to quantify uranium migration, i.e. diffusion and sorption, as a function of mineralogical and geochemical heterogeneities on the host rock scale.
Sorption processes are facies dependent. Migration lengths vary between the Opalinus Clay facies by up to 10 m. Thereby, the geochemistry of the pore water, in particular the partial pressure of carbon dioxide (pCO2), is more decisive for the sorption capacity than the amount of clay minerals. Nevertheless, higher clay mineral quantities compensate geochemical variations. Consequently, sorption processes must be quantified as a function of pore water geochemistry in contact with the mineral assemblage.
Uranium diffusion in the Opalinus Clay is facies independent. Speciation is dominated by aqueous ternary complexes of U(VI) with calcium and carbonate. Differences in the migration lengths between SC and MC diffusion are with +/-5 m negligible. Further, the application of the MC approach highly depends on the quality and availability of the underlying data. Therefore, diffusion processes can be adequately quantified with the SC approach using experimentally determined diffusion coefficients.
The hydrogeological system governs pore water geochemistry within the formation rather than the mineralogy. Diffusive exchange with the adjacent aquifers established geochemical gradients over geological time scales that can enhance migration by up to 25 m. Consequently, uranium sorption processes must be quantified following the identified priority: pCO2 > hydrogeology > mineralogy.
The presented research provides a workflow and orientation for other potential disposal sites with similar pore water geochemistry due to the identified mechanisms and dependencies. With a maximum migration length of 70 m, the retention capacity of the Opalinus Clay with respect to uranium is sufficient to fulfill the German legal minimum requirement of a thickness of at least 100 m.
Development of functionalized waterborne coatings for the production of multifunctional microapsules
(2022)
Umdeutungen des Islams
(2022)
Fanatismus, Krieg und Terror – öffentliche Deutungen und Stereotype über Muslim*innen in der Bundesrepublik.
Ein großer Teil der deutschen Bevölkerung hat heutzutage eine negative Wahrnehmung von Muslim*innen. Ihnen wird pauschal ein Hang zu Gewalt, religiösem Fanatismus, Extremismus und Unterdrückung von Frauen unterstellt. Diese Zuschreibungen bestehen nicht erst seit den Terroranschlägen vom 11. September 2001, sondern haben sich bereits in den drei Jahrzehnten zuvor etabliert.
Alexander Konrad untersucht den Wandel der bundesdeutschen Wahrnehmungen von Muslim*innen von den Siebzigerjahren bis zur Jahrtausendwende. Dabei nimmt er öffentliche Aussagen und Handlungen von Akteur*innen aus Politik, Medien, Wissenschaft, Religionsgemeinschaften und Zivilgesellschaft kritisch in den Blick. Hintergründe, argumentative Überschneidungen und Agenden stehen im Zentrum seiner Analyse. Auch den damaligen Bemühungen um reflektierte Sichtweisen zu Muslim*innen spürt der Autor nach. Mit seiner Studie leistet Alexander Konrad einen fundamentalen Beitrag zur zeithistorischen Dekonstruktion von Denkweisen über Islam und Muslim*innen.
Die Ära Adenauer
(2022)
Dominik Geppert legt die Kontinuitäten wie die vielfältigen Neuanfänge der Adenauer-Ära dar und entwirft in vier Blöcken ein klares Bild der jungen Republik. Er gibt dabei einen aktuellen und verständlichen Überblick über die wichtigsten Ereignisse und Personen.
Die Bundesrepublik, ein Kind des Kalten Krieges, wurde in den ersten beiden Jahrzehnten ihres Bestehens vom wirtschaftlichen Wiederaufbau, von der Etablierung der parlamentarischen Demokratie, von den Anfängen einer zivilen Kultur und dem Ausgleich mit den Westmächten geprägt. Dominik Geppert legt die Kontinuitäten wie die vielfältigen Neuanfänge der Adenauer-Ära dar und entwirft in vier Blöcken ein klares Bild der jungen Republik: Neuanfang und Kontinuität: Die Gründung der Bundesrepublik 1949; Kalter Krieg und Westbindung: Die Außen- und Deutschlandpolitik; Stabilisierung und Wiederaufbau: Wirtschaft und Innenpolitik; Gesellschaft und Kultur in der Bundesrepublik.
As climate change worsens, there is a growing urgency to promote renewable energies and improve their accessibility to society. Here, solar energy harvesting is of particular importance. Currently, metal halide perovskite (MHP) solar cells are indispensable in future solar energy generation research. MHPs are crystalline semiconductors increasingly relevant as low-cost, high-performance materials for optoelectronics. Their processing from solution at low temperature enables easy fabrication of thin film elements, encompassing solar cells and light-emitting diodes or photodetectors. Understanding the coordination chemistry of MHPs in their precursor solution would allow control over the thin film crystallization, the material properties and the final device performance.
In this work, we elaborate on the key parameters to manipulate the precursor solution with the long-term objective of enabling systematic process control. We focus on the nanostructural characterization of the initial arrangements of MHPs in the precursor solutions. Small-angle scattering is particularly well suited for measuring nanoparticles in solution. This technique proved to be valuable for the direct analyzes of perovskite precursor solutions in standard processing concentrations without causing radiation damage. We gain insights into the chemical nature of widely used precursor structures such as methylammonium lead iodide (MAPbI3), presenting first insights into the complex arrangements and interaction within this precursor state. Furthermore, we transfer the preceding results to other more complex perovskite precursors. The influence of compositional engineering is investigated using the addition of alkali cations as an example. As a result, we propose a detailed working mechanism on how the alkali cations suppress the formation of intermediate phases and improve the quality of the crystalline thin film. In addition, we investigate the crystallization process of a tin-based perovskite composition (FASnI3) under the influence of fluoride chemistry. We prove that the frequently used additive, tin fluoride (SnF2), selectively binds undesired oxidized tin (Sn(IV)) in the precursor solution. This prevents its incorporation into the actual crystal structure and thus reduces the defect density of the material. Furthermore, SnF2 leads to a more homogeneous crystal growth process, which results in improved crystal quality of the thin film material.
In total, this study provides a detailed characterization of the complex system of perovskite precursor chemistry. We thereby cover relevant parameters for future MHP solar cell process control, such as (I) the environmental impact based on concentration and temperature (II) the addition of counter ions to reduce the diffuse layer surrounding the precursor nanostructures and (III) the targeted use of additives to eliminate unwanted components selectively and to ensure a more homogeneous crystal growth.
This paper analyzes the effect of new bicycle lanes on traffic volume, congestion, and accidents. Crucially, the new bike lanes replace existing car lanes thereby reducing available space for motorized traffic. In order to obtain causal estimates, I exploit the quasi-random timing and location of the newly built cycle lanes. Using an event study design, a two-way fixed effects model and the synthetic control group method on geo-coded data, I show that the construction of pop-up bike lanes significantly reduced average car speed by 8 to 12 percentage points (p.p.) and up to 16 p.p. in peak traffic hours. In contrast, the results for car volume are modest, while the data does not allow for a conclusive judgment of accidents.
Dieses Papier thematisiert die völkerstrafrechtliche Einordnung rein störender, also nicht zerstörender Cyberoperationen. Nach der erforderlichen Begriffsklärung werden die einzelnen Fragen der Anwendbarkeit des Völkerstrafrechts erörtert und geprüft, welche Tatbestände durch solche Aktionen verwirklicht werden können.
Core-shell upconversion nanoparticles - investigation of dopant intermixing and surface modification
(2022)
Frequency upconversion nanoparticles (UCNPs) are inorganic nanocrystals capable to up-convert incident photons of the near-infrared electromagnetic spectrum (NIR) into higher energy photons. These photons are re-emitted in the range of the visible (Vis) and even ultraviolet (UV) light. The frequency upconversion process (UC) is realized with nanocrystals doped with trivalent lanthanoid ions (Ln(III)). The Ln(III) ions provide the electronic (excited) states forming a ladder-like electronic structure for the Ln(III) electrons in the nanocrystals. The absorption of at least two low energy photons by the nanoparticle and the subsequent energy transfer to one Ln(III) ion leads to the promotion of one Ln(III) electron into higher excited electronic states. One high energy photon will be emitted during the radiative relaxation of the electron in the excited state back into the electronic ground state of the Ln(III) ion. The excited state electron is the result of the previous absorption of at least two low energy photons.
The UC process is very interesting in the biological/medical context. Biological samples (like organic tissue, blood, urine, and stool) absorb high-energy photons (UV and blue light) more strongly than low-energy photons (red and NIR light). Thanks to a naturally occurring optical window, NIR light can penetrate deeper than UV light into biological samples. Hence, UCNPs in bio-samples can be excited by NIR light. This possibility opens a pathway for in vitro as well as in vivo applications, like optical imaging by cell labeling or staining of specific organic tissue. Furthermore, early detection and diagnosis of diseases by predictive and diagnostic biomarkers can be realized with bio-recognition elements being labeled to the UCNPs. Additionally, "theranostic" becomes possible, in which the identification and the treatment of a disease are tackled simultaneously.
For this to succeed, certain parameters for the UCNPs must be met: high upconversion efficiency, high photoluminescence quantum yield, dispersibility, and dispersion stability in aqueous media, as well as availability of functional groups to introduce fast and easy bio-recognition elements. The UCNPs used in this work were prepared with a solvothermal decomposition synthesis yielding in particles with NaYF4 or NaGdF4 as host lattice. They have been doped with the Ln(III) ions Yb3+ and Er3+, which is only one possible upconversion pair. Their upconversion efficiency and photoluminescence quantum yield were improved by adding a passivating shell to reduce surface quenching.
However, the brightness of core-shell UCNPs stays behind the expectations compared to their bulk material (being at least μm-sized particles). The core-shell structures are not clearly separated from each other, which is a topic in literature. Instead, there is a transition layer between the core and the shell structure, which relates to the migration of the dopants within the host lattice during the synthesis. The ion migration has been examined by time-resolved laser spectroscopy and the interlanthanoid resonance energy transfer (LRET) in the two different host lattices from above. The results are
presented in two publications, which dealt with core-shell-shell structured nanoparticles. The core is doped with the LRET-acceptor (either Nd3+ or Pr3+). The intermediate shell serves as an insulation shell of pure host lattice material, whose shell thickness has been varied within one set of samples having the same composition, so that the spatial separation of LRET-acceptor and -donor changes. The outer shell with the same host lattice is doped with the LRET-donor (Eu3+). The effect of the increasing insulation shell thickness is significant, although the LRET cannot be suppressed completely.
Next to the Ln(III) migration within a host lattice, various phase transfer reactions were investigated in order to subsequently perform surface modifications for bioapplications. One result out of this research has been published using a promising ligand, that equips the UCNP with bio-modifiable groups and has good potential for bio-medical applications. This particular ligand mimics natural occurring mechanisms of mussel protein adhesion and of blood coagulation, which is why the UCNPs are encapsulated very effectively. At the same time, bio-functional groups are introduced. In a proof-of-concept, the encapsulated UCNP has been coupled successfully with a dye (which is representative for a biomarker) and the system’s photoluminescence properties have been investigated.
Inspiriert durch die bis dato unveröffentlichten privaten Aufzeichnungen Ingeborg Bachmanns in dem 2017 erschienenen ersten Band Male Oscuro der neuen Ingeborg-Bachmann-Gesamtausgabe der Salzburger Bachmann Edition, untersucht die vorliegende Arbeit die Zusammenhänge zwischen dem Leben und Schreiben der österreichischen Autorin. Dabei werden die gedanklichen Parallelen zwischen den privaten Aufzeichnungen und Bachmanns Roman Malina als Idee für einen neuen Deutungsansatz genutzt. Hierbei steht jedoch bewusst statt einer typisch biografischen Lesart spezifisch die ästhetische Umsetzung der beobachteten Parallelen im Vordergrund, welche mithilfe von narratologischen, stilistischen und linguistischen Elementen auf ihre Stichhaltigkeit geprüft werden.
Die vorliegende Arbeit stellt daraufhin die These auf, dass Malina einen individuellen Verarbeitungsprozess von Traumata beschreibt, welcher gleichzeitig durch die im Text beschriebenen negativen Einflüsse der Gesellschaft auf diesen Prozess auch als eine umfassende Gesellschaftskritik aufgefasst werden kann. Diese Gesellschaftskritik ist jedoch nicht auf eine Faschismus- oder Patriarchatskritik reduziert, sondern lässt sich, gemäß der Ergebnisse dieser Arbeit, auf jegliche Formen des Machtmissbrauchs auf sämtlichen Ebenen der Gesellschaft beziehen. Die These stützt sich dabei auf ein close reading der im Roman beschriebenen traumatischen Erfahrungen, welche sich sowohl auf individuelle traumatische Erfahrungen (Inzest) als auch auf kollektive traumatische Erfahrungen (Holocaust) beziehen und dadurch der im Text veranschaulichten gesellschaftlichen Abwehr dieser Traumata eine besondere Wirkungskraft verleihen. Die narrativ-psychologisch motivierte Untersuchung des Romans knüpft dabei an den jüngeren Forschungsstand an und versucht sich an einer explizit werkimmanent argumentierenden Analyse, um so nahe liegende biografische Fehlschlüsse bewusst zu vermeiden. Nach einer Exposition des Themas und einem kurzen Überblick über die relevante Forschungsliteratur wird im Hauptteil die These handlungslogisch anhand spezifischer Textstellen untersucht und gleichzeitig mit stilistischen und narratologischen Detailanalysen unterstützt. Im Fazit wird die untersuchte These abschließend im Hinblick auf die eigene Erzählpoetik Bachmanns betrachtet und mit intertextuell anknüpfenden Themengebieten erweitert. Das Ende des Romans wird dabei mit Hilfe des narrativ-psychologischen Ansatzes positiv gedeutet, nämlich als die Lösung des im Verlauf des Erzähltextes bearbeiteten Problems: die Auflösung einer Trauma-bedingten Informationsblockade. Damit wird das bereits vielfach interpretierte Ende des Romans nicht als Tod der Ich-Figur gedeutet, sondern als Befreiung eben dieser aus dem Trauma-fördernden System der Romanwelt. Solchermaßen gelesen stellt Bachmann mit Malina einen - im Sinne der von ihr geforderten ‚neuen Literatur’ - durch und durch Erkenntnis anregenden, interdisziplinären Zusammenhang her, welcher die Beziehungen zwischen Trauma und Tabu, Krankheit und Gesellschaft, Opfer und Täter, Verarbeitung und Verdrängung kunstvoll zu beschreiben vermag. Der Roman bricht damit den Bann der Sprachlosigkeit rund um den zweiten Weltkrieg und veranschaulicht eindrucksvoll den individuellen Prozess eines traumatisierten weiblichen Ichs, das vom Vergessen über das Erinnern zum Ansprechen und anschließenden Überwinden seiner Traumata gelangt – und damit beispielhaft die Strukturen von Machtmissbrauch durchbricht.
Functional traits determine biomass dynamics, coexistence and energetics in plankton food webs
(2022)
Plankton food webs are the basis of marine and limnetic ecosystems. Especially aquatic ecosystems of high biodiversity provide important ecosystem services for humankind as providers of food, coastal protection, climate regulation, and tourism. Understanding the dynamics of biomass and coexistence in these food webs is a first step to understanding the ecosystems. It also lays the foundation for the development of management strategies for the maintenance of the marine and freshwater biodiversity despite anthropogenic influences.
Natural food webs are highly complex, and thus often equally complex methods are needed to analyse and understand them well. Models can help to do so as they depict simplified parts of reality. In the attempt to get a broader understanding of the complex food webs, diverse methods are used to investigate different questions.
In my first project, we compared the energetics of a food chain in two versions of an allometric trophic network model. In particular, we solved the problem of unrealistically high trophic transfer efficiencies (up to 70%) by accounting for both basal respiration and activity respiration, which decreased the trophic transfer efficiency to realistic values of ≤30%. Next in my second project I turned to plankton food webs and especially phytoplankton traits. Investigating a long-term data set from Lake Constance we found evidence for a trade-off between defence and growth rate in this natural phytoplankton community. I continued working with this data set in my third project focusing on ciliates, the main grazer of phytoplankton in spring. Boosted regression trees revealed that temperature and predators have the highest influence on net growth rates of ciliates. We finally investigated in my fourth project a food web model inspired by ciliates to explore the coexistence of plastic competitors and to study the new concept of maladaptive switching, which revealed some drawbacks of plasticity: faster adaptation led to higher maladaptive switching towards undefended phenotypes which reduced autotroph biomass and coexistence and increased consumer biomass.
It became obvious that even well-established models should be critically questioned as it is important not to forget reality on the way to a simplistic model. The results showed furthermore that long-term data sets are necessary as they can help to disentangle complex natural processes. Last, one should keep in mind that the interplay between models and experiments/ field data can deliver fruitful insights about our complex world.
Proteine sind an praktisch allen Prozessen in lebenden Zellen maßgeblich beteiligt. Auch in der Biotechnologie werden Proteine in vielfältiger Weise eingesetzt.
Ein Protein besteht aus einer Kette von Aminosäuren. Häufig lagern sich mehrere dieser Ketten zu größeren Strukturen und Funktionseinheiten, sogenannten Proteinkomplexen,
zusammen. Kürzlich wurde gezeigt, dass eine Proteinkomplexbildung bereits während der Biosynthese der Proteine (co-translational) stattfinden kann
und nicht stets erst danach (post-translational) erfolgt. Da Fehlassemblierungen von Proteinen zu Funktionsverlusten und adversen Effekten führen, ist eine präzise und verlässliche Proteinkomplexbildung sowohl für zelluläre Prozesse als auch für biotechnologische Anwendungen essenziell. Mit experimentellen Methoden lassen sich zwar u.a. die Stöchiometrie und die Struktur von Proteinkomplexen bestimmen,
jedoch bisher nicht die Dynamik der Komplexbildung auf unterschiedlichen Zeitskalen. Daher sind grundlegende Mechanismen der Proteinkomplexbildung noch nicht vollständig verstanden. Die hier vorgestellte, auf experimentellen Erkenntnissen aufbauende, computergestützte Modellierung der Proteinkomplexbildung erlaubt eine umfassende Analyse des Einflusses physikalisch-chemischer Parameter
auf den Assemblierungsprozess. Die Modelle bilden möglichst realistisch die experimentellen Systeme der Kooperationspartner (Bar-Ziv, Weizmann-Institut, Israel; Bukau und Kramer, Universität Heidelberg) ab, um damit die Assemblierung von Proteinkomplexen einerseits in einem quasi-zweidimensionalen synthetischen Expressionssystem (in vitro) und andererseits im Bakterium Escherichia coli (in vivo) untersuchen zu können. Mit Hilfe eines vereinfachten Expressionssystems, in dem die Proteine nur an die Chip-Oberfläche, aber nicht aneinander binden können, wird das theoretische Modell parametrisiert. In diesem vereinfachten in-vitro-System durchläuft die Effizienz der Komplexbildung drei Regime – ein bindedominiertes Regime, ein Mischregime und ein produktionsdominiertes Regime. Ihr Maximum erreicht die Effizienz dabei kurz nach dem Übergang vom bindedominierten ins Mischregime und fällt anschließend monoton ab. Sowohl im nicht-vereinfachten in-vitro- als auch im in-vivo-System koexistieren je zwei konkurrierende Assemblierungspfade: Im in-vitro-System erfolgt die Komplexbildung entweder spontan in wässriger Lösung (Lösungsassemblierung) oder aber in einer definierten Schrittfolge an der Chip-Oberfläche (Oberflächenassemblierung); Im in-vivo-System konkurrieren hingegen die co- und die post-translationale Komplexbildung. Es zeigt sich, dass die Dominanz der Assemblierungspfade im in-vitro-System zeitabhängig ist und u.a. durch die Limitierung und Stärke der Bindestellen auf der Chip-Oberfläche beeinflusst werden kann. Im in-vivo-System hat der räumliche Abstand zwischen den Syntheseorten der beiden Proteinkomponenten nur dann einen Einfluss auf die Komplexbildung, wenn die Untereinheiten schnell degradieren. In diesem Fall dominiert die co-translationale Assemblierung auch auf kurzen Zeitskalen deutlich, wohingegen es bei stabilen Untereinheiten zu einem Wechsel von der Dominanz der post- hin zu einer geringen Dominanz der co-translationalen Assemblierung kommt. Mit den in-silico-Modellen lässt sich neben der Dynamik u.a. auch die Lokalisierung der Komplexbildung und -bindung darstellen, was einen Vergleich der theoretischen Vorhersagen mit experimentellen Daten und somit eine Validierung der Modelle ermöglicht. Der hier präsentierte in-silico Ansatz ergänzt die experimentellen Methoden, und erlaubt so, deren Ergebnisse zu interpretieren und neue Erkenntnisse davon abzuleiten.
In der fortwährenden Diskussion zur Familienbesteuerung bewertet der Autor vor dem Hintergrund des deutschen Verfassungsrechts die geltenden Regelungen und mögliche Reformmodelle rechtlich, steuerpolitisch und ökonomisch. Unter dem besonderen Blickwinkel eines seit mehr als 20 Jahren tätigen Steuerberaters kann der Autor die Wirkung des Splittingtarifs und deren Alternativen ökonomisch gut durchdringen.
Die Ehe und Familie stehen unter dem besonderen Schutz der deutschen staatlichen Ordnung. Diese Schutzpflicht aus Art. 6 Abs. 1 GG geht deutlich über ein Abwehrrecht hinaus. Sie gebietet es, die Ehe zu schützen, ihr einen grundsätzlich unantastbaren Kernbereich privater Lebensführung zu gewähren und innerfamiliär staatlicherseits keine bestimmte innereheliche Arbeits- und Aufgabenverteilung vorzuschreiben.
Die Ehe wird häufig als „Keimzelle“ jeglicher menschlichen Gesellschaft bezeichnet. Das erscheint folgerichtig und historisch bedeutsam. Im heutigen Zeitalter jedoch ist sie mehr oder weniger eine Erwerbs-, Konsum- und Verantwortungsgemeinschaft. Insofern stellt sich vornehmlich die Frage nach einer genügenden Rechtfertigung für die Gewährung eines Splittingtarifs.
Ausgangspunkt der umfassenden systematischen Darstellung ist die historischen Entwicklung in Deutschland und den angrenzenden Staaten; insbesondere der heutigen Europäischen Union. Denn in anderen Staaten werden bereits unterschiedliche Modelle wie beispielsweise die Einzel- oder Familienbesteuerung angewendet.
Verfassungsrechtlich hat der Gesetzgeber Veränderungen der gesellschaftlichen Rahmenbedingungen in und für die Familie in seine gesetzgeberischen Entscheidungen zwingend einzubeziehen. Es stellt sich demnach die Frage, ob beispielsweise seit der Entscheidung des Bundesverfassungsgerichts zum Ehegattensplitting im Jahr 1957 relevante Veränderungen eingetreten sind, die eine Änderung der Familienbesteuerung rechtfertigen oder gar erfordern. Die zwischenzeitliche Anerkennung von Lebenspartnerschaften und die Ehe für alle sind Ausdruck einer solchen Veränderung. Sie implizieren die bereits eingetretenen Veränderungen der Lebensverhältnisse. Daher ist die politische Diskussion für eine Veränderung nachvollziehbar. Ob jedoch Alternativen vorzugswürdig sind, wird ausführlich dargestellt.
This paper examines the function that cross-cultural competence (3C) has for NATO in a military context while focusing on two member states and their armed forces: the United States and Germany. Three dimensions were established to analyze 3C internally and externally: dimension A, dealing with 3C within the military organization; dimension B, focusing on 3C in a coalition environment/multicultural NATO contingent, for example while on a mission/training exercise abroad; and dimension C, covering 3C and NATO missions abroad with regard to interaction with the local population.
When developing the research design, the cultural studies-based theory of hegemony constructed by Antonio Gramsci was applied to a comprehensive document analysis of 3C coursework and regulations as well as official documents in order to establish a typification for cross-cultural competence.
As the result, 3C could be categorized as Type I – Ethical 3C, Type II – Hegemonic 3C, and Type III – Dominant 3C. Attributes were assigned according to each type. To validate the established typification, qualitative surveys were conducted with NATO (ACT), the U.S. Armed Forces (USCENTCOM), and the German Armed Forces (BMVg). These interviews validated the typification and revealed a varied approach to 3C in the established dimensions. It became evident that dimensions A and B indicated a prevalence of Type III, which greatly impacts the work atmosphere and effectiveness for NATO (ACT). In contrast, dimension C revealed the use of postcolonial mechanisms by NATO forces, such as applying one’s value systems to other cultures and having the appearance of an occupying force when 3C is not applied (Type I-II). In general, the function of each 3C type in the various dimensions could be determined.
In addition, a comparative study of the document analysis and the qualitative surveys resulted in a canon for culture-general skills. Regarding the determined lack of coherence in 3C correlating with a demonstrably negative impact on effectiveness and efficiency as well as interoperability, a NATO standard in the form of a standardization agreement (STANAG) was suggested based on the aforementioned findings, with a focus on: empathy, cross-cultural awareness, communication skills (including active listening), flexibility and adaptability, and interest. Moreover, tolerance of ambiguity and teachability, patience, observation skills, and perspective-taking could be considered significant. Suspending judgment and respect are also relevant skills here.
At the same time, the document analysis also revealed a lack of coherency and consistency in 3C education and interorganizational alignment. In particular, the documents examined for the U.S. Forces indicated divergent approaches. Furthermore, the interview analysis disclosed a large discrepancy in part between doctrine and actual implementation with regard to the NATO Forces.
Die vorliegende Bachelorarbeit beschäftigt sich mit dem Einfluss von Digitalisierung auf die öffentliche Verwaltung in Deutschland. Den konkreten Untersuchungsschwerpunkt bilden organisationale Routinen. Die Arbeit gibt einen konzeptionellen Überblick über die Begriffe Digitalisierung und organisationale Routinen und leitet daraus Arbeitsdefinitionen ab. Der theoretisch dargelegte Zusammenhang zwischen den beiden Phänomenen wird im Rahmen von drei teilstrukturierten Interviews mit Mitarbeitenden aus unterschiedlichen öffentlichen Verwaltungen untersucht. Die herausgearbeiteten Definitionen wurden den Interviewten vorgestellt und durch ein Repertoire an Fragen die Wahrnehmung des Digitalisierungsstandes i.V.m. Routinen abgefragt.
Die Ergebnisse zeigen, dass digitaler Wandel und Routinen in jedem der interviewten Fachbereiche zumindest unterbewusst wahrgenommen wird. Digitalisierung und organisationale Routinen stehen in Wechselwirkung zueinander, da die wiederholte routinierte Ausführung von Tätigkeiten die Implementierung von Digitalisierung begünstigt. Darüber hinaus führt digitaler Wandel zur Veränderung von Routinen, welche mit einem anfänglichen Mehraufwand verbunden ist. Störungen bei der Implementierung von Digitalisierung bringen eine Starrheit von Routinen mit sich u.A. durch eine fehlende Bereitschaft der Mitarbeitenden. Die grundlegend bestehende Wechselwirkung ist ausschlaggebend für die Schnittstellen zwischen Digitalisierung und organisationalen Routinen in der öffentlichen Verwaltung.
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-Dagmar Hülsenberg: Anwendung naturwissenschaftlicher und kameralistischer Erkenntnisse auf die Verarbeitung von Rohstoffen durch den jungen Alexander von Humboldt
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-Eberhard Schulz-Lüpertz: Alexander von Humboldt und Ulrich Jasper Seetzen – Auf den Spuren eines Helgoland-Briefs
-Ulrich Stottmeister: Der Mineraloge August Schmidt und die Entdeckung der Ural-Diamanten 1829 Teil II: Schmidts wissenschaftlicher Diamanten-Beweis und sein weiteres Schicksal im Ural
-Petra Werner: Ernste Kunst kann nicht gedeihen ohne Gunst. Mäzene und Unterstützer des Malers Albert Berg (1825 – 1884)
-Frank Holl: Hinweis zum Beitrag von Irene Prüfer Leske in HiN, Bd. 22, Nr. 43 (2021)
Der Autor untersucht das System des gerichtlichen Rechtsschutzes gegen beamtenrechtliche Personalauswahlentscheidungen im Hinblick auf dessen tatsächliche Wirksamkeit zur Durchsetzung des Grundrechts auf gleichen Zugang zu öffentlichen Ämtern aus Art. 33 Abs. 2 GG. Maßstab der Wirksamkeitsprüfung ist die Rechtsschutzgarantie aus Art. 19 Abs. 4 S. 1 GG. Berücksichtigt werden insbesondere die Modifikationen der etablierten Rechtsschutzdogmatik durch das Urteil des BVerwG vom 04.11.2010. Der Autor konstatiert, dass Bewerbern um ein öffentliches Amt nun zwar ein formell lückenloser Primärrechtsschutz eingeräumt wird. Dessen praktische Wirksamkeit ist jedoch durch zahlreiche prozessuale Besonderheiten und die Handhabung des dem Dienstherrn bei der Auswahlentscheidung zugebilligten weiten Beurteilungs- und Ermessensspielraums erheblich eingeschränkt. Der Autor folgert, dass der geforderte effektive gerichtliche Rechtsschutz nur durch eine rechtsschutzfreundliche Gestaltung des behördlichen Auswahlverfahrens gewährleistet werden kann, und leitet bestimmte organisatorische Mindestanforderungen an das Auswahlverfahren her.