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Using magneto-optical Faraday and Kerr measurements, we investigate the magnetic and magnetooptical properties of a thick Bi-substituted gadolinium iron garnet film over a broad range of wavelengths (250-850 nm) and temperatures (150-300 K), including the magnetization compensation point, TM. We observe an exchange-bias-like effect in the vicinity of TM. By slightly changing the sample temperature, we can precisely tune the bias field, which reaches a magnitude 6 times higher than the coercive field. We explain this phenomenon by considering the short-range superexchange interaction and a change in the magnetic behavior when moving from the surface to the bulk of the film. This finding may lead to the development of single-film magneto-optical devices based on the exchange-bias effect.
This study deals with the facile synthesis of Fe1-xS nanoparticle-containing nitrogen-doped porous carbon membranes (denoted as Fe1-xS/N-PCMs) via vacuum carbonization of hybrid porous poly(ionic liquid) (PIL) membranes, and their successful use as a sulfur host material to mitigate the shuttle effect in lithium-sulfur (Li-S) batteries. The hybrid porous PIL membranes as the sacrificial template were prepared via ionic crosslinking of a cationic PIL with base-neutralized 1,1 '-ferrocenedicarboxylic acid, so that the iron source was molecularly incorporated into the template. The carbonization process was investigated in detail at different temperatures, and the chemical and porous structures of the carbon products were comprehensively analyzed. The Fe1-xS/N-PCMs prepared at 900 degrees C have a multimodal pore size distribution with a satisfactorily high surface area and well-dispersed iron sulfide nanoparticles to physically and chemically confine the LiPSs. The sulfur/Fe1-xS/N-PCM composites were then tested as electrodes in Li-S batteries, showing much improved capacity, rate performance and cycle stability, in comparison to iron sulfide-free, nitrogen-doped porous carbon membranes.
Psychometric evaluation of the German version of the Variety Seeking Tendency Scale (VARSEEK)
(2021)
As part of a healthy diet, guidelines recommend eating a variety of foods to reduce risks associated with malnutrition. However, whether people follow this recommendation substantially depends on their willingness to try unfamiliar foods, also referred to as food neophilia. This study aimed at comprehensively validating the German version of the Variety Seeking Tendency Scale (VARSEEK), a common instrument to assess food neophilia. Two independent sub-studies were conducted to examine the German VARSEEK's psychometric properties. Study 1 (N = 532, aged 18-91 years) and Study 2 (N = 468, aged 18-73 years) each comprised a German community sample. Data were collected both online and via a paper-pencil version. Whereas Study 1 included an EFA, Study 2 comprised a CFA, analyses of the VARSEEK's reliability and construct validity, and different explorative group comparisons. EFA and CFA results supported the original scale's unidimensionality. Internal consistency (alpha = .93) and test-retest reliability (r = .87) of the scale were high. VARSEEK scores were positively associated with openness, sensation seeking, and extraversion and negatively associated with food neophobia, general neophobia, and trait anxiety. Construct validity was further established by showing positive associations with ratings of familiarity with and willingness to try familiar and unfamiliar foods. Whereas group comparisons revealed no significant differences for sex, age, and weight status, analyses showed that people who belonged to the upper class were more food neophilic than those assigned to the lower and middle class. Findings further underscore that the German VARSEEK is a reliable and valid instrument for the assessment of food neophilia in the German population.
Vibrational relaxation of adsorbates is a sensitive tool to probe energy transfer at gas/solid and liquid/solid interfaces. The most direct way to study relaxation dynamics uses time-resolved spectroscopy. Here we report on a non-equilibrium ab initio molecular dynamics (NE-AIMD) methodology to model vibrational relaxation of OH vibrations on a hydroxylated, water-covered alpha-Al2O3(0001) surface. In our NE-AIMD approach, after exciting selected O-H bonds their coupling to surface phonons and to the water adlayer is analyzed in detail, by following both the energy flow in time, as well as the time-evolution of Vibrational Density of States (VDOS) curves. The latter are obtained from Time-dependent Correlation Functions (TCFs) and serve as prototypical, generic representatives of time-resolved vibrational spectra. As most important results, (i) we find a few-picosecond lifetime of the excited modes and (ii) identify both hydrogen-bonded aluminols and water molecules in the adsorbed water layer as main dissipative channels, while the direct coupling to Al2O3 surface phonons is of minor importance on the timescales of interest. Our NE-AIMD/TCF methodology is powerful for complex adsorbate systems, in principle even reacting ones, and opens a way towards time-resolved vibrational spectroscopy.
Elucidation of the reaction mechanism for the synthesis of ZnGeN2 through Zn2GeO4 ammonolysis
(2021)
Ternary II-IV-N-2 materials have been considered as a promising class of materials that combine photovoltaic performance with earth-abundance and low toxicity. When switching from binary III-V materials to ternary II-IV-N-2 materials, further structural complexity is added to the system that may influence its optoelectronic properties. Herein, we present a systematic study of the reaction of Zn2GeO4 with NH3 that produces zinc germanium oxide nitrides, and ultimately approach stoichiometric ZnGeN2, using a combination of chemical analyses, X-ray powder diffraction and DFT calculations. Elucidating the reaction mechanism as being dominated by Zn and O extrusion at the later reaction stages, we give an insight into studying structure-property relationships in this emerging class of materials.
Phase equilibria that are relevant for the growth of Bi2MO4 have been studied experimentally, and the ternary phase diagrams of Bi2O3-PdO2-Pd and Bi2O3-Cu2O-CuO and its isopleth section Bi2O3-CuO were redetermined. It is shown that every melting and crystallization process is always accompanied by a redox process at the phase boundary and that for both title compounds, the valence of the transition metal is lowered during melting. Vice versa, during crystal growth, O-2 must be transported through the melt to the phase boundary. Based on these new insights provided by our thermodynamic studies, Bi2CuO4 single crystals with a length of up to 7 cm and a diameter of 6 mm were grown by the OFZ technique to be used for investigations of magnetic, electronic and thermal transport properties. The grown crystals were characterized by powder X-ray diffraction, Laue, magnetization and specific heat measurements.
Demokratie und politische Bildung stehen in einem sich zugewandten Verhältnis. Doch folgt daraus, dass politische Urteile stets demokratisch sein müssen? Der Beitrag diskutiert diese Frage vor dem Hintergrund der derzeitigen Debatte um antidemokratische Bewegungen in der Gesellschaft, der Rolle politischer Bildung als Förderin von Demokratie und der individuellen Herausforderung für Lehrpersonen in der Unterrichtspraxis.
Qualitative Inhaltsanalyse
(2021)
Die qualitative Inhaltsanalyse dient als Auswertungsinstrument für Textmaterial, kann aber auch für die Analyse von Ton- und Bildmaterial genutzt werden. Anders als die quantitative Inhaltsanalyse zielt sie darauf ab, dem Material auch Informationen zu entnehmen, auf die ausschließlich interpretativ geschlossen werden kann. Die qualitative Inhaltsanalyse knüpft an die hermeneutische Tradition des Verstehens an. Der Verstehensprozess wird jedoch in einen vordefinierten, theorie- und regelgeleiteten Forschungsablauf gebettet, um dem wissenschaftlichen Anspruch an Systematik und Intersubjektivität nachzukommen.
Background
Building on the Realistic Accuracy Model, this paper explores whether it is easier for teachers to assess the achievement of some students than others. Accordingly, we suggest that certain individual characteristics of students, such as extraversion, academic self-efficacy, and conscientiousness, may guide teachers' evaluations of student achievement, resulting in more appropriate judgements and a stronger alignment of assigned grades with students' actual achievement level (as measured using standardized tests).
Aims
We examine whether extraversion, academic self-efficacy, and conscientiousness moderate the relations between teacher-assigned grades and students' standardized test scores in mathematics.
Sample
This study uses a representative sample of N = 5,919 seventh-grade students in Germany (48.8% girls; mean age: M = 12.5, SD = 0.62) who participated in a national, large-scale assessment focusing on students' academic development.
Methods
We specified structural equation models to examine the inter-relations of teacher-assigned grades with students' standardized test scores in mathematics, Big Five personality traits, and academic self-efficacy, while controlling for students' socioeconomic status, gender, and age.
Results
The correlation between teacher-assigned grades and standardized test scores in mathematics was r = .40. Teacher-assigned grades more closely related to standardized test scores when students reported higher levels of conscientiousness (beta = .05, p = .002). Students' extraversion and academic self-efficacy did not moderate the relationship between teacher-assigned grades and standardized test scores.
Conclusions
Our findings indicate that students' conscientiousness is a personality trait that seems to be important when it comes to how closely mathematics teachers align their grades to standardized test scores.
Künstliche Intelligenz (KI) ist eine Dual-Use-Technologie: Einerseits kann sie zur Erhöhung der Cybersicherheit eingesetzt werden, andererseits können feindliche Angriffe mittels KI effektiver durchgeführt werden. KI-Systeme und Roboter können darüber hinaus Gegenstand neuartiger Angriffe werden.
Dies wirft eine Reihe neuer Rechtsfragen auf, die das Werk eingehend behandelt, etwa:
Welche Vorgaben trifft das deutsche IT-Sicherheitsrecht spezifisch für KI-Systeme sowie smarte Robotik?
Welche Gewährleistungsrechte bestehen bei IT-Sicherheitsmängeln von Robotern bzw. KI-Systemen?
Wer haftet wann bei der Verwendung smarter Robotik oder von KI-Anwendungen, sofern es zur Verletzung von IT-Sicherheitsstandards kommt?
Auch und gerade in der Finanzwirtschaft gelten Blockchain-Anwendungen als taugliches Instrument zur Transaktionsabsicherung sowie Effizienzsteigerung. Wegen ihrer technischen Ausgestaltung, die – zumindest im Ausgangspunkt – eine dezentrale Struktur aufweist und rückwirkende Änderungen sowie v. a. Löschungen grundsätzlich nicht zulässt, was jeweils vertrauensschaffende Wirkungen zeitigen kann, ergeben sich jedoch kaum lösbare Friktionen mit datenschutzrechtlichen Vorgaben. Dies gilt zumindest dann, wenn man die Vorzüge der Blockchain nicht aufgeben bzw. ihr technisches Design nicht stark aufweichen möchte. Die Problematik gipfelt letztendlich in der grundlegenden Frage, ob Recht vor bestimmten Technologien, welche die normativen Vorgaben qua Design nicht umsetzen können, kapitulieren sollte. Damit im engen Zusammenhang steht der noch zu selten diskutierte Aspekt, dass es den bisher erwogenen Anwendungsfällen der Blockchain (v. a. außerhalb von FinTech-Szenarien) womöglich an substantiellem Mehrwert mangelt, der es rechtfertigen würde, etwa bei datenschutzrechtlichen Vorgaben de lege lata und de lege ferenda Milde walten zu lassen.
Das EU-Datenwirtschaftsrecht nimmt langsam Form an. Dabei gilt es sich zu vergegenwärtigen, dass sich dieses neue Teilrechtsgebiet letztlich auf „digitalisierte Informationen“ bezieht (I.). Es gesellt sich – mit einigen Schnittmengen – „neben“ das Datenschutzrecht (II.). Nachdem sich zunächst v. a. die Rechtswissenschaft mit Fragen zur besseren Nutzbarkeit, Zugänglichkeit und Handelbarkeit von Daten mit oder ohne Personenbezug beschäftigt hat, ist insofern nunmehr insbesondere der EU-Gesetzgeber als Treiber der Materie auszumachen (III.). Dies unterstreicht die Praxisrelevanz der zugrundeliegenden Fragen.
On 21 April 2021, the European Commission presented its long-awaited proposal for a Regulation “laying down harmonized rules on Artificial Intelligence”, the so-called “Artificial Intelligence Act” (AIA). This article takes a critical look at the proposed regulation. After an introduction (1), the paper analyzes the unclear preemptive effect of the AIA and EU competences (2), the scope of application (3), the prohibited uses of Artificial Intelligence (AI) (4), the provisions on high-risk AI systems (5), the obligations of providers and users (6), the requirements for AI systems with limited risks (7), the enforcement system (8), the relationship of the AIA with the existing legal framework (9), and the regulatory gaps (10). The last section draws some final conclusions (11).
Dass Technologien wie Machine Learning-Anwendungen oder Big bzw. Smart Data- Verfahren unbedingt Daten in ausreichender Menge und Güte benötigen, erscheint inzwischen als Binsenweisheit. Vor diesem Hintergrund hat insbesondere der EU-Gesetzgeber für sich zuletzt ein neues Betätigungsfeld entdeckt, indem er versucht, auf unterschiedlichen Wegen Anreize zum Datenteilen zu schaffen, um Innovation zu kreieren. Hierzu zählt auch eine geradezu wohltönend mit ,,Datenaltruismus‘‘ verschlagwortete Konstellation. Der Beitrag stellt die diesbezüglichen Regulierungserwägungen auf supranationaler Ebene dar und nimmt eine erste Analyse vor.
This study is trying to understand the pre-eruptive magma storage and crystallization conditions of the Middle Miocene aged, silica-saturated trachytic rocks of the Afyon Volcanic Complex (AVC) in Western Anatolia, Turkey. Those rocks can be divided by their high K2O, K2O/Na2O ratio and Mg# into two groups, namely the intermediate-potassic (IPG) and the ultrapotassic (UPG). Here we are comparing calculated pressure (P) - temperature (T) conditions derived from geothermobarometric calculations of natural samples with results of high-pressure, high-temperature phase equilibria experiments. IPG samples are richer in silica (57-64 wt% SiO2), whereas UPG samples show intermediate SiO2 contents of 56-58 wt%. UPG are having high K2O contents ((>)9 wt %), K2O/Na2O ratios ((>)10 wt%) and Mg# values (75-77). IPG phenocrysts comprise plagioclase + biotite + amphibole + clinopyroxene +/- orthopyroxene +/- sanidine +/- phlogopite and oxides, while UPG mineralogical assemblage consists of amphibole + phlogopite + clinopyroxene + olivine + sanidine and oxides. IPG and UPG are enriched in Large-Ion Lithophile Elements (LILE), and both have negative anomalies in Nb, Sr, Zr and Ti elements. Additionally, IPG shows positive anomalies in Pb. Both IPG and UPG display enrichment in Light Rare Earth Elements (LREE), while IPG shows a more significant negative anomaly in Eu when compared to UPG. Plagioclase fractionation may play a role in magma generation. In IPG samples Ni and Cr values range between (3.3-18.8 ppm) and (2.6-27.8 ppm), respectively; whereas UPG samples have (119.1-120.7 ppm) Ni and (212.1-219.9 ppm) Cr. Dy/Yb ratios of IPG and UPG are higher than 2 and may indicate that garnet was present in the source. Geothermobarometric calculations for natural IPG clinopyroxene-melt pairs imply higher PT conditions (Dogan-Kulahci et al., 2015), while in this study high-pressure/high-temperature (HP/HT) phase equilibria experiments recreated the natural mineral assemblage at 2-4 kbar, 6-9 km and c. 900 degrees C. New plagioclase-melt calculations have confirmed lower mean magma storage temperatures, which are closer to the experimental results but still slightly elevated. Thus, trace element results of the natural rocks and experimental data may imply that a deep garnet-bearing magma source mixed with shallower magmas (IPG) was feeding the volcanic eruption.
Clubs of autocrats
(2021)
While scholars have argued that membership in Regional Organizations (ROs) can increase the likelihood of democratization, we see many autocratic regimes surviving in power albeit being members of several ROs. This article argues that this is the case because these regimes are often members in "Clubs of Autocrats" that supply material and ideational resources to strengthen domestic survival politics and shield members from external interference during moments of political turmoil. The argument is supported by survival analysis testing the effect of membership in autocratic ROs on regime survival between 1946 to 2010. It finds that membership in ROs composed of more autocratic member states does in fact raise the likelihood of regime survival by protecting incumbents against democratic challenges such as civil unrest or political dissent. However, autocratic RO membership does not help to prevent regime breakdown due to autocratic challenges like military coups, potentially because these types of threats are less likely to diffuse to other member states. The article thereby adds to our understanding of the limits of democratization and potential reverse effects of international cooperation, and contributes to the literature addressing interdependences of international and domestic politics in autocratic regimes.
The sharing economy gains momentum and develops a major economic impact on traditional markets and firms. However, only rudimentary theoretical and empirical insights exist on how sharing networks, i.e., focal firms, shared goods providers and customers, create and capture value in their sharing-based business models. We conduct a qualitative study to find key differences in sharing-based business models that are decisive for their value configurations. Our results show that (1) customization versus standardization of shared goods and (2) the centralization versus particularization of property rights over the shared goods are two important dimensions to distinguish value configurations. A second, quantitative study confirms the visibility and relevance of these dimensions to customers. We discuss strategic options for focal firms to design value configurations regarding the two dimensions to optimize value creation and value capture in sharing networks. Firms can use this two-dimensional search grid to explore untapped opportunities in the sharing economy.
The sharing economy gains momentum and develops a major economic impact on traditional markets and firms. However, only rudimentary theoretical and empirical insights exist on how sharing networks, i.e., focal firms, shared goods providers and customers, create and capture value in their sharing-based business models. We conduct a qualitative study to find key differences in sharing-based business models that are decisive for their value configurations. Our results show that (1) customization versus standardization of shared goods and (2) the centralization versus particularization of property rights over the shared goods are two important dimensions to distinguish value configurations. A second, quantitative study confirms the visibility and relevance of these dimensions to customers. We discuss strategic options for focal firms to design value configurations regarding the two dimensions to optimize value creation and value capture in sharing networks. Firms can use this two-dimensional search grid to explore untapped opportunities in the sharing economy.
Effects of manganese on genomic integrity in the multicellular model organism Caenorhabditis elegans
(2021)
Although manganese (Mn) is an essential trace element, overexposure is associated with Mn-induced toxicity and neurological dysfunction. Even though Mn-induced oxidative stress is discussed extensively, neither the underlying mechanisms of the potential consequences of Mn-induced oxidative stress on DNA damage and DNA repair, nor the possibly resulting toxicity are characterized yet. In this study, we use the model organism Caenorhabditis elegans to investigate the mode of action of Mn toxicity, focusing on genomic integrity by means of DNA damage and DNA damage response. Experiments were conducted to analyze Mn bioavailability, lethality, and induction of DNA damage. Different deletion mutant strains were then used to investigate the role of base excision repair (BER) and dePARylation (DNA damage response) proteins in Mn-induced toxicity. The results indicate a dose- and time-dependent uptake of Mn, resulting in increased lethality. Excessive exposure to Mn decreases genomic integrity and activates BER. Altogether, this study characterizes the consequences of Mn exposure on genomic integrity and therefore broadens the molecular understanding of pathways underlying Mn-induced toxicity. Additionally, studying the basal poly(ADP-ribosylation) (PARylation) of worms lacking poly(ADP-ribose) glycohydrolase (PARG) parg-1 or parg-2 (two orthologue of PARG), indicates that parg-1 accounts for most of the glycohydrolase activity in worms.
Research on corporate entrepreneurship—venturing activities by established corporations—has received increasing scholarly attention. We employ bibliometric methods to analyze the literature on corporate entrepreneurship published over the last five decades. Based on the results of citation and co-citation analyses, we reveal central works in the field and how they are interconnected. We investigate the underlying intellectual structure of the field. Our findings provide evidence of the growing maturity and interdisciplinarity of corporate entrepreneurship and provide insight into research themes. We find that resource-based view and its extensions still remain the predominant theoretical perspectives in the field. Drawing on these findings, we suggest directions for future research.
Uruguay River is the most important river in western Rio Grande do Sul, separating Brazil from Argentina and Uruguay. However, its pollution is of great concern due to agricultural activities in the region and the extensive use of pesticides. In a long term, this practice leads to environmental pollution, especially to the aquatic system. The objective of this study was to analyze the physicochemical characteristics, metals and pesticides levels in water samples obtained before and after the planting and pesticides' application season from three sites: Uruguay River and two minor affluents, Mezomo Dam and Salso Stream. For biomonitoring, the free-living nematode Caenorhabditis elegans was used, which were exposed for 24 h. We did not find any significant alteration in physicochemical parameters. In the pre- and post-pesticides' samples we observed a residual presence of three pesticides (tebuconazole, imazethapyr, and clomazone) and metals which levels were above the recommended (As, Hg, Fe, and Mn). Exposure to both pre- and post-pesticides' samples impaired C. elegans reproduction and post-pesticides samples reduced worms' survival rate and lifespan. PCA analysis indicated that the presence of metals and pesticides are important variables that impacted C. elegans biological endpoints. Our data demonstrates that Uruguay River and two affluents are contaminated independent whether before or after pesticides' application season. In addition, it reinforces the usefulness of biological indicators, since simple physicochemical analyses are not sufficient to attest water quality and ecological safety.
Prosodic boundaries can be used to disambiguate the syntactic structure of coordinated name sequences (coordinates). To answer the question whether disambiguating prosody is produced in a situationally dependent or independent manner and to contribute to our understanding of the nature of the prosody-syntax link, we systematically explored variability in the prosody of boundary productions of coordinates evoked by different contextual settings in a referential communication task. Our analysis focused on prosodic boundaries produced to distinguish sequences with different syntactic structures (i.e., with or without internal grouping of the constituents). In German, these prosodic boundaries are indicated by three major prosodic cues: f0-range, final lengthening, and pause. In line with the Proximity/Anti-Proximity principle of the syntax-prosody model by Kentner and Fery (2013), speakers clearly use all three cues for constituent grouping and prosodically mark groups within and at their right boundary, indicating that prosodic phrasing is not a local phenomenon. Intra-individually, we found a rather stable prosodic pattern across contexts. However, inter-individually speakers differed from each other with respect to the prosodic cue combinations that they (consistently) used to mark the boundaries. Overall, our data speak in favour of a close link between syntax and prosody and for situational independence of disambiguating prosody.
Human infants can segment action sequences into their constituent actions already during the first year of life. However, work to date has almost exclusively examined the role of infants' conceptual knowledge of actions and their outcomes in driving this segmentation. The present study examined electrophysiological correlates of infants' processing of lower-level perceptual cues that signal a boundary between two actions of an action sequence. Specifically, we tested the effect of kinematic boundary cues (pre-boundary lengthening and pause) on 12-month-old infants' (N = 27) processing of a sequence of three arbitrary actions, performed by an animated figure. Using the Event-Related Potential (ERP) approach, evidence of a positivity following the onset of the boundary cues was found, in line with previous work that has found an ERP positivity (Closure Positive Shift, CPS) related to boundary processing in auditory stimuli and action sequences in adults. Moreover, an ERP negativity (Negative Central, Nc) indicated that infants' encoding of the post-boundary action was modulated by the presence or absence of prior boundary cues. We therefore conclude that 12-month-old infants are sensitive to lower-level perceptual kinematic boundary cues, which can support segmentation of a continuous stream of movement into individual action units.
Scaling agriculture to the globally rising population demands new approaches for future crop production such as multilayer and multitrophic indoor farming. Moreover, there is a current trend towards sustainable local solutions for aquaculture and saline agriculture. In this context, halophytes are becoming increasingly important for research and the food industry. As Salicornia europaea is a highly salt-tolerant obligate halophyte that can be used as a food crop, indoor cultivation with saline water is of particular interest. Therefore, finding a sustainable alternative to the use of seawater in non-coastal regions is crucial. Our goal was to determine whether natural brines, which are widely distributed and often available in inland areas, provide an alternative water source for the cultivation of saline organisms. This case study investigated the potential use of natural brines for the production of S. europaea. In the control group, which reflects the optimal growth conditions, fresh weight was increased, but there was no significant difference between the treatment groups comparing natural brines with artificial sea water. A similar pattern was observed for carotenoids and chlorophylls. Individual components showed significant differences. However, within treatments, there were mostly no changes. In summary, we showed that the influence of the different chloride concentrations was higher than the salt composition. Moreover, nutrient-enriched natural brine was demonstrated to be a suitable alternative for cultivation of S. europaea in terms of yield and nutritional quality. Thus, the present study provides the first evidence for the future potential of natural brine waters for the further development of aquaculture systems and saline agriculture in inland regions.
Das Angebot digitaler Plattformen ist mittlerweile auch im Maschinen- und Anlagenbau weit verbreitet. Dabei konnte in den letzten Jahren der Trend verzeichnet werden, dass die Herstellerunternehmen von Maschinen und Anlagen nicht mehr ausschließlich physische Produkte veräußern, sondern zusätzliche auf das Produkt abgestimmte Dienstleistungen, wie bspw. digitale Services. Dieser Wandel kann einen großen Einfluss auf die Veränderung des Geschäftsmodells haben und je nach Komplexität der digitalen Plattformen unterschiedliche Ausmaße annehmen, die auch strategische Entscheidungen bestimmen können. In diesem Beitrag wird eine Klassifizierung der digitalen Plattformen im deutschen Maschinen- und Anlagenbau vorgenommen, mithilfe derer unterschiedliche Plattformtypen auf Grundlage ihrer Funktionszusammensetzung identifiziert werden. Demnach können bspw. Plattformen, über die lediglich grundlegende Funktionen wie die Verwaltung von Maschinen angeboten werden, von umfangreicheren Plattformen unterschieden werden, die eine höhere Komplexität aufweisen und somit einen größeren Einfluss auf die Veränderung des Geschäftsmodells haben. Diese Einteilung unterschiedlicher Plattformtypen kann Unternehmen im Maschinen- und Anlagenbau dabei unterstützen, strategische Entscheidungen bezüglich der Entwicklung und des Angebots digitaler Plattformen zu treffen und eine Einordnung ihrer digitalen Plattform im Wettbewerb vorzunehmen.
Humans are frequently exposed to a variety of endocrine disrupting chemicals (EDCs), which can cause harmful effects, e.g. disturbance of growth, development and reproduction, and cancer (UBA, 2016). EDCs are often components of synthetically manufactured products. Materials made of plastics, building materials, electronic items, textiles or cosmetic products can be particularly contaminated (Ain et al., 2021). One group of EDCs that has gained increased interest in recent years is phthalates. They are used as plasticizers in plastic materials to which people are daily exposed to. Phthalate plasticizers exert their harmful effects among others via activation of the estrogen receptor α (ERα), the estrogen receptor β (ERβ) and via inhibition of the androgen receptor (AR). Some phthalates have already been classified by the EU as Cancerogenic-, Mutagenic-, Reprotoxic- (CMR) substances and their use in industry has been restricted. After oral ingestion, phthalates are metabolized and are finally excreted with the urine. Numerous toxicological studies exist on phthalates, but mainly with the parent substances, not with their primary and secondary metabolites. In the course of the restriction of phthalates by the EU, the phthalate-free plasticizer di-isononylcyclohexane-1,2-dicarboxylate (DINCH®), was introduced to the market. So far, almost no toxicologically relevant properties have been identified for DINCH®. However, the effects of DINCH® have only been studied in animal experiments and, as with phthalates, almost exclusively with the parent substance. However, toxic effects of a particular compound may be induced by its metabolites and not by the parent compound itself. Therefore, potential endocrine effects of 15 phthalates, 19 phthalate metabolites, DINCH®, and five of its metabolites were investigated using reporter gene assays on the ERα, ERβ, and the AR. In addition, studies of the influence of some selected plasticizers on peroxisome proliferator-activated receptor α (PPARα) and peroxisome proliferator-activated receptor γ (PPARγ) activity were performed. Furthermore, a H295R steroidogenesis assay was performed to determine the influence of DINCH® and its metabolites on estradiol or testosterone synthesis. Analysis of the experiments shows that the phthalates either stimulated or inhibited ERα and ERβ activity and inhibited AR activity, whereas the phthalate metabolites did not affect the activity of these human hormone receptors. In contrast, metabolites of di-(2-ethylhexyl) phthalate (DEHP) stimulated transactivation of the human PPARα and PPARγ in analogous reporter gene assays, although DEHP itself did not activate these nuclear receptors. Therefore, primary and secondary phthalate metabolites appear to exert different effects at the molecular level compared to the parent compounds. Similarly, the results showed that the phthalate-free plasticizer DINCH® itself did not affect the activity of ERα, ERβ, AR, PPARα and PPARγ, while the DINCH® metabolites were shown to activate all these receptors. In the case of AR, DINCH® metabolites mainly enhanced AR activity stimulated by dihydrotestosterone (DHT). In the H295R steroidogenesis assay, neither DINCH® nor any of its metabolites affected estradiol or testosterone synthesis. Primary and secondary metabolites of DINCH® thus exert different effects at the molecular level than DINCH® itself. However, all these in vitro effects of DINCH® metabolites were observed only at high concentrations, which were about three orders of magnitude higher than the reported DINCH® metabolite concentrations in human urine. Therefore, the in vitro data does not support the assumption that DINCH® or any of the metabolites studied could have significant endocrine effects in vivo at relevant exposure levels in humans. Following the demonstration of direct and indirect endocrine effects of the studied plasticizers, a new effect-based in vitro 3D screening tool for toxicity assays of non-genotoxic carcinogens was developed using estrogen receptor-negative (ER-) MCF10-A cells and estrogen receptor-positive (ER+) MCF-12A cells. This arose from the background that breast cancer is the most common cancer occurring in women and estrogenic substances, such as phthalates, can probably influence the disease. The human mammary epithelial cell lines MCF-10A and MCF-12A form well-differentiated acini-like structures when cultured in three-dimensional Matrigel culture for a period of 20 days. The model should make it possible to detect substance effects on cell differentiation and growth, on mammary cell acini, and to differentiate between estrogenic and non-estrogenic effects at the same time. In the present study, both cell lines were tested for their suitability as an effect-based in vitro assay system for non-genotoxic carcinogens. An Automated Acinus Detection And Morphological Evaluation (ADAME) software solution has been developed for automatic acquisition of acinus images and determination of morphological parameters such as acinus size, lumen size, and acinus roundness. Several test substances were tested for their ability to affect acinus formation and cellular differentiation. Human epithelial growth factor (EGF) stimulated acinus growth for both cell lines, while all trans retinoic acid (RA) inhibited acinar growth. The potent estrogen 17β-estradiol had no effect on acinus formation of MCF-10A cells but resulted in larger MCF-12A acini. Thus, the parallel use of both cell lines together with the developed high content screening and evaluation tool allows the rapid identification of the estrogenic and cancerogenic properties of a given test compound. The morphogenesis of the acini was only slightly affected by the test substances. On the one hand, this suggests a robust test system, on the other hand, it probably cannot detect low-potent estrogenic compounds such as phthalates or DINCH®. The advantage of the robustness of the system, however, may be that vast numbers of "positive" results with questionable biological relevance could be avoided, such as those observed in sensitive reporter gene assays.
Biological maturation has been shown to affect male youths' responses to plyometric training (PT). However, to date, no researcher has examined the effect of maturation on the effects of PT in female youth. We undertook the first controlled intervention study to examine this, focusing on adaptive responses to countermovement jump (CMJ), reactive strength index (RSI), and change of direction (COD) performance in groups of female youth divided by maturation status (years from peak height velocity [PHV]). The training program lasted 7 weeks with subjects undertaking 2 sessions of PT per week. In the mid-PHV group, there was a small increase (effect size; 90% confidence interval = 0.40; -0.23 to 1.03) in CMJ performance. No changes were observed in the post-PHV group (0.02; -0.68 to 0.72). For RSI, there was a moderate increase in the mid-PHV group (0.94; 0.29-1.59) with only a trivial increase in the post-PHV group (0.06; -0.65 to 0.76). The intervention exerted no positive effect on COD performance in any group. Plyometric training seems to enhance CMJ and RSI in female youth, although the magnitude of adaptation could be affected by maturation status. A twice-per-week program of multidirectional jumping and hopping, with bilateral and unilateral components, can be used as a preparatory precursor to physical education classes or recreational sport.
Violence in adolescent relationships is a common problem with numerous negative short- and long-term consequences. Because most of the evidence on teen dating violence (TDV) synthesized in reviews comes from North American studies, this review aimed to compile evidence on prevalence rates of TDV based on studies identified for Europe only. Specifically, we considered different forms of TDV victimization and perpetration, gender differences, and its measurement. A systematic literature search of the most popular databases Ebsco and PubMed yielded a total of N = 34 studies, with most of the studies identified for Spain, and only a few studies in other European countries. In sum, the results revealed a great variability in prevalence rates across and within the European countries, a common pattern of gender differences, and a wide range of applied measures, corresponding with the evidence from the North American studies. Implications for future research and policy were discussed.
Prevalence of sexual aggression victimization and perpetration in a German university student sample
(2021)
This study examined the prevalence of sexual aggression perpetration and victimization in a sample of 1,172 students (755 female, 417 male) from four universities in Germany. All participants were asked about both victimization by, and perpetration of, sexual aggression since the age of 14 years, using the Sexual Aggression and Victimization Scale (SAV-S). Prevalence rates were established for different coercive strategies, sexual acts, and victim-perpetrator relationships. Both same-sex and opposite-sex victim-perpetrator constellations were examined. The overall victimization rate was 62.1% for women and 37.5% for men. The overall perpetration rate was 17.7% for men and 9.4% for women. Prevalence rates of both victimization and perpetration were higher for participants who had sexual contacts with both opposite-sex and same-sex partners than for participants with exclusively opposite-sex partners. Significant overlap was found between victim and perpetrator status for men and women as well as for participants with only opposite-sex and both opposite-sex and same-sex partners. A disparity between (higher) victimization and (lower) perpetration reports was found for both men and women, suggesting a general underreporting of perpetration rather than a gendered explanation in terms of social desirability or the perception of consent cues. The findings are placed in the international research literature on the prevalence of sexual aggression before and after the #metoo campaign, and their implications for prevention efforts are discussed.
The ubiquitin-proteasome-system (UPS) is a cellular cascade involving three enzymatic steps for protein ubiquitination to target them to the 26S proteasome for proteolytic degradation. Several components of the UPS have been shown to be central for regulation of defense responses during infections with phytopathogenic bacteria. Upon recognition of the pathogen, local defense is induced which also primes the plant to acquire systemic resistance (SAR) for enhanced immune responses upon challenging infections. Here, ubiquitinated proteins were shown to accumulate locally and systemically during infections with Psm and after treatment with the SAR-inducing metabolites salicylic acid (SA) and pipecolic acid (Pip). The role of the 26S proteasome in local defense has been described in several studies, but the potential role during SAR remains elusive and was therefore investigated in this project by characterizing the Arabidopsis proteasome mutants rpt2a-2 and rpn12a-1 during priming and infections with Pseudomonas. Bacterial replication assays reveal decreased basal and systemic immunity in both mutants which was verified on molecular level showing impaired activation of defense- and SAR-genes. rpt2a-2 and rpn12a-1 accumulate wild type like levels of camalexin but less SA. Endogenous SA treatment restores local PR gene expression but does not rescue the SAR-phenotype. An RNAseq experiment of Col-0 and rpt2a-2 reveal weak or absent induction of defense genes in the proteasome mutant during priming. Thus, a functional 26S proteasome was found to be required for induction of SAR while compensatory mechanisms can still be initiated.
E3-ubiquitin ligases conduct the last step of substrate ubiquitination and thereby convey specificity to proteasomal protein turnover. Using RNAseq, 11 E3-ligases were found to be differentially expressed during priming in Col-0 of which plant U-box 54 (PUB54) and ariadne 12 (ARI12) were further investigated to gain deeper understanding of their potential role during priming.
PUB54 was shown to be expressed during priming and /or triggering with virulent Pseudomonas. pub54 I and pub54-II mutants display local and systemic defense comparable to Col-0. The heavy-metal associated protein 35 (HMP35) was identified as potential substrate of PUB54 in yeast which was verified in vitro and in vivo. PUB54 was shown to be an active E3-ligase exhibiting auto-ubiquitination activity and performing ubiquitination of HMP35. Proteasomal turnover of HMP35 was observed indicating that PUB54 targets HMP35 for ubiquitination and subsequent proteasomal degradation. Furthermore, hmp35-I benefits from increased resistance in bacterial replication assays. Thus, HMP35 is potentially a negative regulator of defense which is targeted and ubiquitinated by PUB54 to regulate downstream defense signaling. ARI12 is transcriptionally activated during priming or triggering and hyperinduced during priming and triggering. Gene expression is not inducible by the defense related hormone salicylic acid (SA) and is dampened in npr1 and fmo1 mutants consequently depending on functional SA- and Pip-pathways, respectively. ARI12 accumulates systemically after priming with SA, Pip or Pseudomonas. ari12 mutants are not altered in resistance but stable overexpression leads to increased resistance in local and systemic tissue. During priming and triggering, unbalanced ARI12 levels (i.e. knock out or overexpression) leads to enhanced FMO1 activation indicating a role of ARI12 in Pip-mediated SAR. ARI12 was shown to be an active E3-ligase with auto-ubiquitination activity likely required for activation with an identified ubiquitination site at K474. Mass spectrometrically identified potential substrates were not verified by additional experiments yet but suggest involvement of ARI12 in regulation of ROS in turn regulating Pip-dependent SAR pathways.
Thus, data from this project provide strong indications about the involvement of the 26S proteasome in SAR and identified a central role of the two so far barely described E3-ubiquitin ligases PUB54 and ARI12 as novel components of plant defense.
Land Brandenburg
(2021)
Das über 860 Jahre alte deutsche Land BB liegt im Nordosten Ds zwischen Elbe und Oder. Es umschließt die Bundeshauptstadt BE, die als Einheitsgemeinde zugleich ein eigenes Land bildet. Potsdam als Landeshauptstadt ist mit 176.000 E. die größte Stadt in BB. Mit 29.482 qkm (8,3 % von D) zählt die Mark zu den flächenreichsten Bundesländern.
Angepasste Pathogene besitzen eine Reihe von Virulenzmechanismen, um pflanzliche Immunantworten unterhalb eines Schwellenwerts der effektiven Resistenz zu unterdrücken. Dadurch sind sie in der Lage sich zu vermehren und Krankheiten auf einem bestimmten Wirt zu verursachen. Eine essentielle Virulenzstrategie Gram-negativer Bakterien ist die Translokation von sogenannten Typ-III Effektorproteinen (T3Es) direkt in die Wirtszelle. Dort stören diese die Immunantwort des Wirts oder fördern die Etablierung einer für das Pathogen günstigen Umgebung. Eine kritische Komponente der Pflanzenimmunität gegen eindringende Pathogene ist die schnelle transkriptionelle Umprogrammierung der angegriffenen Zelle. Viele adaptierte bakterielle Pflanzenpathogene verwenden T3Es, um die Induktion Abwehr-assoziierter Gene zu stören. Die Aufklärung von Effektor-Funktionen, sowie die Identifikation ihrer pflanzlichen Zielproteine sind für das Verständnis der bakteriellen Pathogenese essentiell. Im Rahmen dieser Arbeit sollte das Typ-III Effektorprotein XopS aus Xanthomonas campestris pv. vesicatoria (Xcv) funktionell charakterisiert werden. Zudem lag hier ein besonderer Fokus auf der Untersuchung der Wechselwirkung zwischen XopS und seinem in Vorarbeiten identifizierten pflanzlichen Interaktionspartner WRKY40, einem transkriptionellen Regulator der Abwehr-assoziierten Genexpression. Es konnte gezeigt werden, dass XopS ein essentieller Virulenzfaktor des Phytopathogens Xcv während der präinvasiven Immunantwort ist. So zeigten xopS-defiziente Xcv Bakterien bei einer Inokulation der Blattoberfläche suszeptibler Paprika Pflanzen eine deutlich reduzierte Virulenz im Vergleich zum Xcv Wildtyp. Die Translokation von XopS durch Xcv, sowie die ektopische Expression von XopS in Arabidopsis oder N. benthamiana verhinderte das Schließen von Stomata als Reaktion auf Bakterien bzw. einem Pathogen-assoziierten Stimulus, wobei zudem gezeigt werden konnte, dass dies in einer WRKY40-abhängigen Weise geschieht. Weiter konnte gezeigt werden, dass XopS in der Lage ist, die Expression Abwehr-assoziierter Gene zu manipulieren. Dies deutet darauf hin, dass XopS sowohl in die prä-als auch in die postinvasive, apoplastische Abwehr eingreift. Phytohormon-Signalnetzwerke spielen während des Aufbaus einer effizienten pflanzlichen Immunantwort eine wichtige Rolle. Hier konnte gezeigt werden, dass XopS mit genau diesen Signalnetzwerken zu interferieren scheint. Eine ektopische Expression des Effektors in Arabidopsis führte beispielsweise zu einer signifikanten Induktion des Phytohormons Jasmonsäure (JA), während eine Infektion von suszeptiblen Paprika Pflanzen mit einem xopS-defizienten Xcv Stamm zu einer ebenfalls signifikanten Akkumulation des Salicylsäure (SA)-Gehalts führte.
So kann zu diesem Zeitpunkt vermutet werden, dass XopS die Virulenz von Xcv fördert, indem JA-abhängige Signalwege induziert werden und es gleichzeitig zur Unterdrückung SA-abhängiger Signalwege kommt. Die Virus-induzierte Genstilllegung des XopS Interaktionspartners WRKY40a in Paprika erhöhte die Toleranz der Pflanze gegenüber einer Xcv Infektion, was darauf hindeutet, dass es sich bei diesem Protein um einen transkriptionellen Repressor pflanzlicher Immunantworten handelt. Die Hypothese, dass WRKY40 die Abwehr-assoziierte Genexpression reprimiert, konnte hier über verschiedene experimentelle Ansätze bekräftigt werden. So wurde beispielsweise gezeigt, dass die Expression von verschiedenen Abwehrgenen einschließlich des SA-abhängigen Gens PR1 und die des Negativregulators des JA-Signalwegs JAZ8 von WRKY40 gehemmt wird. Um bei einem Pathogenangriff die Abwehr-assoziierte Genexpression zu gewährleisten, muss WRKY40 als Negativregulator abgebaut werden. Vorarbeiten zeigten, dass WRKY40 über das 26S Proteasom abgebaut wird. In der hier vorliegenden Studie konnte weiter bestätigt, dass der T3E XopS zu einer Stabilisierung des WRKY40 Proteins führt, indem er auf bislang ungeklärte Weise dessen Abbau über das 26S Proteasom verhindert. Die Ergebnisse aus der hier vorliegenden Arbeit lassen die Vermutung zu, dass die Stabilisierung des Negativregulators der Immunantwort WRKY40 seitens XopS dazu führt, dass eine darüber vermittelte Manipulation der Abwehr-assoziierten Genexpression, sowie eine Umsteuerung phytohormoneller Wechselwirkungen die Ausbreitung von Xcv auf suszeptiblen Paprikapflanzen fördert. Ein weiteres Ziel dieser Arbeit war es, weitere potentielle in planta Interaktionspartner von XopS zu identifizieren die für seine Interaktion mit WRKY40 bzw. für die Aufschlüsselung seines Wirkmechanismus relevant sein könnten. So konnte die Deubiquitinase UBP12 als weiterer pflanzlicher Interaktionspartner sowohl von XopS als auch von WRKY40 gefunden werden. Dieses Enzym ist in der Lage, die Ubiquitinierung von Substratproteinen zu modifizieren und seine Funktion könnte somit ein Bindeglied zwischen XopS und dessen Interferenz mit dem proteasomalen Abbau von WRKY40 sein. Während einer kompatiblen Xcv-Wirtsinteraktion führte die Virus-induzierte Genstilllegung von UBP12 zu einer reduzierten Resistenz der Pflanze gegenüber des Pathogens Xcv, was auf dessen positiv-regulatorische Wirkung während der Immunantwort hindeutet. Zudem zeigten Western Blot Analysen, dass das Protein WRKY40 bei einer Herunterregulierung von UBP12 akkumuliert und dass diese Akkumulation von der Anwesenheit des T3Es XopS zusätzlich verstärkt wird. Weiterführende Analysen zur biochemischen Charakterisierung der XopS/WRKY40/UBP12 Interaktion sollten in Zukunft durchgeführt werden, um den genauen Wirkmechanismus des XopS T3Es weiter aufzuschlüsseln.
COVID-19
(2021)
We investigate how the economic consequences of the pandemic and the government-mandated measures to contain its spread affect the self-employed — particularly women — in Germany. For our analysis, we use representative, real-time survey data in which respondents were asked about their situation during the COVID-19 pandemic. Our findings indicate that among the self-employed, who generally face a higher likelihood of income losses due to COVID-19 than employees, women are about one-third more likely to experience income losses than their male counterparts. We do not find a comparable gender gap among employees. Our results further suggest that the gender gap among the self-employed is largely explained by the fact that women disproportionately work in industries that are more severely affected by the COVID-19 pandemic. Our analysis of potential mechanisms reveals that women are significantly more likely to be impacted by government-imposed restrictions, e.g., the regulation of opening hours. We conclude that future policy measures intending to mitigate the consequences of such shocks should account for this considerable variation in economic hardship.
Transitioning German road transport partially to hydrogen energy is among the possibilities being discussed to help meet national climate targets. This study investigates impacts of a hypothetical, complete transition from conventionally-fueled to hydrogen-powered German transport through representative scenarios. Our results show that German emissions change between -179 and +95 MtCO(2)eq annually, depending on the scenario, with renewable-powered electrolysis leading to the greatest emissions reduction, while electrolysis using the fossilintense current electricity mix leads to the greatest increase. German energy emissions of regulated pollutants decrease significantly, indicating the potential for simultaneous air quality improvements. Vehicular hydrogen demand is 1000 PJ annually, requiring 446-525 TWh for electrolysis, hydrogen transport and storage, which could be supplied by future German renewable generation, supporting the potential for CO2-free hydrogen traffic and increased energy security. Thus hydrogen-powered transport could contribute significantly to climate and air quality goals, warranting further research and political discussion about this possibility.
Reacting, fast and slow
(2021)
The COVID-19 pandemic created extraordinary challenges for governments to safeguard the well-being of their people. To what extent has leaders' reliance on scientific advice shaped government responses to the COVID-19 outbreak? We argue that leaders who tend to orient themselves on expert advice realized the extent of the crisis earlier. Consequently, these governments would adopt containment measures relatively quickly, despite the high uncertainty they faced. Over time, differences in government responses based on the use of science would dissipate due to herding effects. We test our argument on data combining 163 government responses to the pandemic with national- and individual-level characteristics. Consistent with our argument, we find that countries governed by politicians with a stronger technocratic mentality, approximated by holding a PhD, adopted restrictive containment measures faster in the early, but not in the later, stages of the crisis. This importance of expert-based leadership plausibly extends to other large-scale societal crises.
A detailed investigation of the energy levels of perylene-3,4,9,10-tetracarboxylic tetraethylester as a representative compound for the whole family of perylene esters was performed. It was revealed via electrochemical measurements that one oxidation and two reductions take place. The bandgaps determined via the electrochemical approach are in good agreement with the optical bandgap obtained from the absorption spectra via a Tauc plot. In addition, absorption spectra in dependence of the electrochemical potential were the basis for extensive quantum-chemical calculations of the neutral, monoanionic, and dianionic molecules. For this purpose, calculations based on density functional theory were compared with post-Hartree-Fock methods and the CAM-B3LYP functional proved to be the most reliable choice for the calculation of absorption spectra. Furthermore, spectral features found experimentally could be reproduced with vibronic calculations and allowed to understand their origins. In particular, the two lowest energy absorption bands of the anion are not caused by absorption of two distinct electronic states, which might have been expected from vertical excitation calculations, but both states exhibit a strong vibronic progression resulting in contributions to both bands.
Donors of development assistance for health typically provide funding for a range of disease focus areas, such as maternal health and child health, malaria, HIV/AIDS, and other infectious diseases. But funding for each disease category does not match closely its contribution to the disability and loss of life it causes and the cost-effectiveness of interventions. We argue that peer influences in the social construction of global health priorities contribute to explaining this misalignment. Aid policy-makers are embedded in a social environment encompassing other donors, health experts, advocacy groups, and international officials. This social environment influences the conceptual and normative frameworks of decision-makers, which in turn affect their funding priorities. Aid policy-makers are especially likely to emulate decisions on funding priorities taken by peers with whom they are most closely involved in the context of expert and advocacy networks. We draw on novel data on donor connectivity through health IGOs and health INGOs and assess the argument by applying spatial regression models to health aid disbursed globally between 1990 and 2017. The analysis provides strong empirical support for our argument that the involvement in overlapping expert and advocacy networks shapes funding priorities regarding disease categories and recipient countries in health aid.
Mechanical behaviors of granite after thermal treatment under loading and unloading conditions
(2021)
Understanding the mechanical behaviors of granite after thermal treatment under loading and unloading conditions is of utmost relevance to deep geothermal energy recovery. In the present study, a series of loading and unloading triaxial compression tests (20, 40 and 60 MPa) on granite specimens after exposure to different temperatures (20, 200, 300, 400, 500 and 600 degrees C) was carried out to quantify the combined effects of thermal treatment and loading/unloading stress conditions on granite strength and deformation. Changes in the microstructure of granite exposed to high temperatures were revealed by optical microscopy. The experimental results indicate that both, thermal treatment and loading/unloading stress conditions, degrade the mechanical behaviors and further decrease the carrying capacity of granite. The gradual degradation of the mechanical characteristics of granite after thermal treatment is mainly associated with the evolution of thermal micro-cracks based on optical microscopy observations. The unloading stress state induces the extension of tension cracks parallel to the axial direction, and thus, the mechanical properties are degraded. Temperatures above 400 degrees C have a more significant influence on the mechanical characteristics of granite than the unloading treatment, whereby 400 degrees C can be treated as a threshold temperature for the delineation of significant deterioration. This study is expected to support feasibility and risk assessments by means of providing data for analytical calculations and numerical simulations on granite exposed to high temperatures during geothermal energy extraction.
This paper starts from the premise that Western states are connected to some of the harms refugees suffer from. It specifically focuses on the harm of acts of misrecognition and its relation to epistemic injustice that refugees suffer from in refugee camps, in detention centers, and during their desperate attempts to find refuge. The paper discusses the relation between hermeneutical injustice and acts of misrecognition, showing that these two phenomena are interconnected and that acts of misrecognition are particularly damaging when (a) they stretch over different contexts, leaving us without or with very few safe spaces, and (b) they dislocate us, leaving us without a community to turn to. The paper then considers the ways in which refugees experience acts of misrecognition and suffer from hermeneutical injustice, using the case of unaccompanied children at the well-known and overcrowded camp Moria in Greece, the case of unsafe detention centers in Libya, and the case of the denial to assistance on the Mediterranean and the resulting pushbacks from international waters to Libya as well as the preventable drowning of refugees in the Mediterranean to illustrate the arguments. Finally, the paper argues for specific duties toward refugees that result from the prior arguments on misrecognition and hermeneutical injustice.
Both ground- and satellite-based airglow imaging have significantly contributed to understanding the low-latitude ionosphere, especially the morphology and dynamics of the equatorial ionization anomaly (EIA). The NASA Global-scale Observations of the Limb and Disk (GOLD) mission focuses on far-ultraviolet airglow images from a geostationary orbit at 47.5 degrees W. This region is of particular interest at low magnetic latitudes because of the high magnetic declination (i.e., about -20 degrees) and proximity of the South Atlantic magnetic anomaly. In this study, we characterize an exciting feature of the nighttime EIA using GOLD observations from October 5, 2018 to June 30, 2020. It consists of a wavelike structure of a few thousand kilometers seen as poleward and equatorward displacements of the EIA-crests. Initial analyses show that the synoptic-scale structure is symmetric about the dip equator and appears nearly stationary with time over the night. In quasi-dipole coordinates, maxima poleward displacements of the EIA-crests are seen at about +/- 12 degrees latitude and around 20 and 60 degrees longitude (i.e., in geographic longitude at the dip equator, about 53 degrees W and 14 degrees W). The wavelike structure presents typical zonal wavelengths of about 6.7 x 10(3) km and 3.3 x 10(3) km. The structure's occurrence and wavelength are highly variable on a day-to-day basis with no apparent dependence on geomagnetic activity. In addition, a cluster or quasi-periodic wave train of equatorial plasma depletions (EPDs) is often detected within the synoptic-scale structure. We further outline the difference in observing these EPDs from FUV images and in situ measurements during a GOLD and Swarm mission conjunction.
Selenium (Se) is known to contribute to several vital physiological functions in mammals: antioxidant defense, fertility, thyroid hormone metabolism, and immune response. Growing evidence indicates the crucial role of Se and Se-containing selenoproteins in the brain and brain function. As for the other essential trace elements, dietary Se needs to reach effective concentrations in the central nervous system (CNS) to exert its functions. To do so, Se-species have to cross the blood-brain barrier (BBB) and/or blood-cerebrospinal fluid barrier (BCB) of the choroid plexus. The main interface between the general circulation of the body and the CNS is the BBB. Endothelial cells of brain capillaries forming the so-called tight junctions are the primary anatomic units of the BBB, mainly responsible for barrier function. The current review focuses on Se transport to the brain, primarily including selenoprotein P/low-density lipoprotein receptor-related protein 8 (LRP8, also known as apolipoprotein E receptor-2) dependent pathway, and supplementary transport routes of Se into the brain via low molecular weight Se-species. Additionally, the potential role of Se and selenoproteins in the BBB, BCB, and neurovascular unit (NVU) is discussed. Finally, the perspectives regarding investigating the role of Se and selenoproteins in the gut-brain axis are outlined.
To systematically add functionality to nanoscale polymer switches, an understanding of their responsive behavior is crucial. Herein, solvent vapor stimuli are applied to thin films of a diblock copolymer consisting of a short poly(methyl methacrylate) (PMMA) block and a long poly(N-isopropylmethacrylamide) (PNIPMAM) block for realizing ternary nanoswitches. Three significantly distinct film states are successfully implemented by the combination of amphiphilicity and co-nonsolvency effect. The exposure of the thin films to nitrogen, pure water vapor, and mixed water/acetone (90 vol%/10 vol%) vapor switches the films from a dried to a hydrated (solvated and swollen) and a water/acetone-exchanged (solvated and contracted) equilibrium state. These three states have distinctly different film thicknesses and solvent contents, which act as switch positions "off," "on," and "standby." For understanding the switching process, time-of-flight neutron reflectometry (ToF-NR) and spectral reflectance (SR) studies of the swelling and dehydration process are complemented by information on the local solvation of functional groups probed with Fourier-transform infrared (FTIR) spectroscopy. An accelerated responsive behavior beyond a minimum hydration/solvation level is attributed to the fast build-up and depletion of the hydration shell of PNIPMAM, caused by its hydrophobic moieties promoting a cooperative hydration character.
Accurate and precise characterization of cirrus cloud geometrical and optical properties is essential for better constraining their radiative footprint. A lidar-based retrieval scheme is proposed here, with its performance assessed on fine spatio-temporal observations over the Arctic site of Ny-Alesund, Svalbard. Two contributions related to cirrus geometrical (dynamic Wavelet Covariance Transform (WCT)) and optical properties (constrained Klett) are reported. The dynamic WCT rendered cirrus detection more robust, especially for thin cirrus layers that frequently remained undetected by the classical WCT method. Regarding optical characterization, we developed an iterative scheme for determining the cirrus lidar ratio (LRci) that is a crucial parameter for aerosol - cloud discrimination. Building upon the Klett-Fernald method, the LRci was constrained by an additional reference value. In established methods, such as the double-ended Klett, an aerosol-free reference value is applied. In the proposed constrained Klett, however, the reference value was approximated from cloud-free or low cloud optical depth (COD up to 0.2) profiles and proved to agree with independent Raman estimates. For optically thin cirrus, the constrained Klett inherent uncertainties reached 50% (60-74%) in terms of COD (LRci). However, for opaque cirrus COD (LRci) uncertainties were lower than 10% (15%). The detection method discrepancies (dynamic versus static WCT) had a higher impact on the optical properties of low COD layers (up to 90%) compared to optically thicker ones (less than 10%). The constrained Klett presented high agreement with two established retrievals. For an exemplary cirrus cloud, the constrained Klett estimated the COD355 (LRci355) at 0.28 +/- 0.17 (29 +/- 4 sr), the double-ended Klett at 0.27 +/- 0.15 (32 +/- 4 sr) and the Raman retrievals at 0.22 +/- 0.12 (26 +/- 11 sr). Our approach to determine the necessary reference value can also be applied in established methods and increase their accuracy. In contrast, the classical aerosol-free assumption led to 44 sr LRci overestimation in optically thin layers and 2-8 sr in thicker ones. The multiple scattering effect was corrected using Eloranta (1998) and accounted for 50-60% extinction underestimation near the cloud base and 20-30% within the cirrus layers.
"Water-in-salt" (WIS) electrolytes have emerged as an excellent superconcentrated ionic medium for high-power energy storage systems such as supercapacitors due to their extended working potential compared to the conventional dilute aqueous electrolyte. In this work, we have investigated the performance of WIS supercapacitors using hollow carbon nanoplates as electrodes and compared it to that based on the conventional "salt-in-water" electrolytes. Moreover, the potentiostatic electrochemical impedance spectroscopy has been employed to provide an insightful look into the charge transport properties, which also, for the first time, reveals the formation of a solid-electrolyte interphase (SEI and their temperature-dependent impedance for charge transfer and adsorption. Furthermore, the effect of temperature on the electrochemical performance of the WIS supercapacitors in the temperature range from 15 to 60 degrees C has been studied, which presents a gravimetric capacitance of 128 F g(-1) and a volumetric capacitance of 197.12 F cm(-3) at 55 degrees C compared to 87.5 F g(-1) and 134.75 F cm(-3) at 15 degrees C. The in-depth understanding about the formation of SEI layer and the electrochemical performance at different temperatures for WIS supercapacitors will assist the efforts toward designing better aqueous electrolytes for supercapacitors.
Feminismus - das ist nicht nur für Männer, sondern auch für einige Frauen immer noch ein bedrohliches Wort, selbst oder gerade in Zeiten von #MeToo. Liegt das daran, dass viele gar nicht wissen, was Feminismus ist und worauf er hinarbeitet? Gibt es den einen Feminismus? Was hat Feminismus eigentlich mit Sexismus zu tun? Und was mit unseren Beziehungen? Offener Frauenhass ist in unserer Gesellschaft mittlerweile weitgehend geächtet. Aber auch nach über fünfzehn Jahren mit einer Frau an der Regierungsspitze sind wir noch längst nicht in der Gleichberechtigung angekommen. Im Gegenteil: Weiterhin strukturiert Sexismus geschlechtsspezifische Alltagserfahrungen, bis hinein in unsere Intimbeziehungen, wo die Grenzen zwischen Lust und sexueller Gewalt schnell verschwimmen. Die Philosophin und Schriftstellerin Hilkje Hänel deckt die Mechanismen sexueller Objektifizierung und männlichen Anspruchsdenkens auf. Sie zeigt, wie Frauen oft in die sexistischen Alltagsstrukturen verstrickt sind, an denen auch viele Männer leiden. Ihr zugängliches Buch ist das Plädoyer für einen Feminismus, von dem alle etwas haben - und vor dem niemand Angst haben muss.
The digitalization of public administration is increasingly moving forward. This systematic literature review analyzes empirical studies that explore the impacts of digitalization projects (n=93) in the public sector. Bibliometrically, only a few authors have published several times on this topic so far. Most studies focusing on impact come from the US or China, and are related to Computer Science. In terms of content, the majority of examined articles studies services to citizens, and therefore consider them when measuring impact. A classification of the investigated effects by dimensions of public value shows that the analysis of utilitarian-instrumental values, such as efficiency or performance, is prevalent. More interdisciplinary cooperation is needed to research the impact of digitalization in the public sector. The different dimensions of impact should be linked more closely. In addition, research should focus more on the effects of digitalization within administration.
Background: Chronic ankle instability, developing from ankle sprain, is one of the most common sports injuries. Besides it being an ankle issue, chronic ankle instability can also cause additional injuries. Investigating the epidemiology of chronic ankle instability is an essential step to develop an adequate injury prevention strategy. However, the epidemiology of chronic ankle instability remains unknown. Therefore, the purpose of this study was to investigate the epidemiology of chronic ankle instability through valid and reliable self-reported tools in active populations.
Methods: An electronic search was performed on PubMed and Web of Science in July 2020. The inclusion criteria for articles were peer-reviewed, published between 2006 and 2020, using one of the valid and reliable tools to evaluate ankle instability, determining chronic ankle instability based on the criteria of the International Ankle
Consortium, and including the outcome of epidemiology of chronic ankle instability. The risk of bias of the included studies was evaluated with an adapted tool for the sports injury review method.
Results: After removing duplicated studies, 593 articles were screened for eligibility. Twenty full-texts were screened and finally nine studies were included, assessing 3804 participants in total. The participants were between 15 and 32 years old and represented soldiers, students, athletes and active individuals with a history of ankle sprain. The prevalence of chronic ankle instability was 25%, ranging between 7 and 53%. The prevalence of chronic ankle instability within participants with a history of ankle sprains was 46%, ranging between 9 and 76%. Five included studies identified chronic ankle instability based on the standard criteria, and four studies applied adapted exclusion criteria to conduct the study. Five out of nine included studies showed a low risk of bias.
Conclusions: The prevalence of chronic ankle instability shows a wide range. This could be due to the different exclusion criteria, age, sports discipline, or other factors among the included studies. For future studies, standardized criteria to investigate the epidemiology of chronic ankle instability are required. The epidemiology of
CAI should be prospective. Factors affecting the prevalence of chronic ankle instability should be investigated and clearly described.
The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p=0.001, r=0.43) and for the amplitude variation (p=0.003, r=0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p=0.013, r=0.42) and MMGbra (p=0.048, r=0.39) as well as regarding the mean frequency (p=0.004, r=0.48) and amplitude variation of MMGpect (p=0.033, r=0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p=0.022, r=0.33; CV: p=0.004, r=0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.
The rising standard language in Early New High German (1350–1650) provides particularly interesting cases for the question of missing heads on all levels of language structure. A well-known example are subordinate clauses lacking a finite auxiliary verb, traditionally called Afinite Constructions. Based on new data, drawn from two treebanks of Early New High German, the present paper will briefly sketch the distribution of ACs, before establishing that they are in fact a type of ellipsis and do not cluster with other non-finite clauses in German. The remainder of the paper addresses the question what kind of information is missing in ACs and how this information is retrieved. Obviously, auxiliary drop in ENHG represents a type of ellipsis rarely attested in present-day German.
Development of chronic pain after a low back pain episode is associated with increased pain sensitivity, altered pain processing mechanisms and the influence of psychosocial factors. Although there is some evidence that multimodal therapy (such as behavioral or motor control therapy) may be an important therapeutic strategy, its long-term effect on pain reduction and psychosocial load is still unclear. Prospective longitudinal designs providing information about the extent of such possible long-term effects are missing. This study aims to investigate the long-term effects of a homebased uni- and multidisciplinary motor control exercise program on low back pain intensity, disability and psychosocial variables. 14 months after completion of a multicenter study comparing uni- and multidisciplinary exercise interventions, a sample of one study center (n = 154) was assessed once more. Participants filled in questionnaires regarding their low back pain symptoms (characteristic pain intensity and related disability), stress and vital exhaustion (short version of the Maastricht Vital Exhaustion Questionnaire), anxiety and depression experiences (the Hospital and Anxiety Depression Scale), and pain-related cognitions (the Fear Avoidance Beliefs Questionnaire). Repeated measures mixed ANCOVAs were calculated to determine the long-term effects of the interventions on characteristic pain intensity and disability as well as on the psychosocial variables. Fifty four percent of the sub-sample responded to the questionnaires (n = 84). Longitudinal analyses revealed a significant long-term effect of the exercise intervention on pain disability. The multidisciplinary group missed statistical significance yet showed a medium sized long-term effect. The groups did not differ in their changes of the psychosocial variables of interest. There was evidence of long-term effects of the interventions on pain-related disability, but there was no effect on the other variables of interest. This may be partially explained by participant's low comorbidities at baseline. Results are important regarding costless homebased alternatives for back pain patients and prevention tasks. Furthermore, this study closes the gap of missing long-term effect analysis in this field.
Mechanotendography
(2021)
The mechanotendography (MTG) is a method for analyzing the mechanical oscillations of tendons during muscular actions. The aim of this investigation was to evaluate the technical reliability of a piezo-based measurement system used for MTG. The reliability measurements were performed by using audio samples played by a subwoofer. The thereby generated pressure waves were recorded by a piezo-based measurement system. An audio of 40 Hz sine oscillations and four different formerly in vivo recorded MTG-signals were converted into audio files and were used as test signals. Five trials with each audio were performed and one audio was used for repetition trials on another day. The signals’ correlation was estimated by Spearman (MCC) and intraclass correlation coefficients (ICC(3,1)), Cronbach’s alpha (CA) and by mean distances (MD). All parameters were compared between repetition and randomized matched signals. The repetition trials show high correlations (MCC: 0.86 ± 0.13, ICC: 0.89 ± 0.12, CA: 0.98 ± 0.03), low MD (0.03 ± 0.03V) and differ significantly from the randomized matched signals (MCC: 0.15 ± 0.10, ICC: 0.17 ± 0.09, CA: 0.37 ± 0.16, MD: 0.19 ± 0.01V) (p = 0.001 – 0.043). This speaks for an excellent reliability of the measurement system. Presuming the skin above superficial tendons oscillates adequately, we estimate this tool as valid for the application in musculoskeletal system.
The olfactomotor system is especially investigated by examining the sniffing in reaction to olfactory stimuli. The motor output of respiratory-independent muscles was seldomly considered regarding possible influences of smells. The Adaptive Force (AF) characterizes the capability of the neuromuscular system to adapt to external forces in a holding manner and was suggested to be more vulnerable to possible interfering stimuli due to the underlying complex control processes. The aim of this pilot study was to measure the effects of olfactory inputs on the AF of the hip and elbow flexors, respectively. The AF of 10 subjects was examined manually by experienced testers while smelling at sniffing sticks with neutral, pleasant or disgusting odours. The reaction force and the limb position were recorded by a handheld device. The results show, inter alia, a significantly lower maximal isometric AF and a significantly higher AF at the onset of oscillations by perceiving disgusting odours compared to pleasant or neutral odours (p < 0.001). The adaptive holding capacity seems to reflect the functionality of the neuromuscular control, which can be impaired by disgusting olfactory inputs. An undisturbed functioning neuromuscular system appears to be characterized by a proper length tension control and by an earlier onset of mutual oscillations during an external force increase. This highlights the strong connection of olfaction and motor control also regarding respiratory-independent muscles.
The high solids semicontinuous emulsion polymerization of polyvinyl acetate using poly (vinyl alcohol-co-vinyl acetate) as protective colloid is investigated by optical spectroscopy. The suitability of Photon Density Wave (PDW) spectroscopy as inline Process Analytical Technology (PAT) for emulsion polymerization processes at high solid contents (>40% (w/w)) is studied and evaluated. Inline data on absorption and scattering in the dispersion is obtained in real-time. The radical polymerization of vinyl acetate to polyvinyl acetate using ascorbic acid and sodium persulfate as redox initiator system and poly (vinyl alcohol-co-vinyl acetate) as protective colloid is investigated. Starved-feed radical emulsion polymerization yielded particle sizes in the nanometer size regime. PDW spectroscopy is used to monitor the progress of polymerization by studying the absorption and scattering properties during the synthesis of dispersions with increasing monomer amount and correspondingly decreasing feed rate of protective colloid. Results are compared to particle sizes determined with offline dynamic light scattering (DLS) and static light scattering (SLS) during the synthesis.
Religious Mapping Erbil (RME) is a joint project of teams from the Catholic University in Erbil (CUE), Salahaddin University-Erbil (SUE) and Tishk International University (TIU) under the guidance of the University of Potsdam (UP). From 2018 to 2022, the project was financed by the German Academic Exchange Service (DAAD).
This project involves scholars of various disciplines including religious studies, Islamic studies, English language, applied computing, and computer engineering. The research is a cooperation of students, PhD candidates and advanced scholars.
The project attempts to display the religious diversity in Erbil, the fast-changing capital of Iraqi Kurdistan. Unlike a census or a survey, which focuses on individuals, RME presents the locations (mosques, churches, synagogues, temples and other venues) together with the history and social profiles of the congregations meeting there. [insert tiny map or part of it]
The data were obtained by visiting the locations, observing their services, interviewing community leaders (mostly imams and priests), evaluating information from the Ministry of Endowment and Religious Affairs, and by consulting websites. All investigations followed the same pattern, consisting of (I) spatiotemporal and (III) social dimensions, framed by (II) religious performance.
Adaptive Force (AF) reflects the capability of the neuromuscular system to adapt adequately to external forces with the intention of maintaining a position or motion. One specific approach to assessing AF is to measure force and limb position during a pneumatically applied increasing external force. Through this method, the highest (AFmax), the maximal isometric (AFisomax) and the maximal eccentric Adaptive Force (AFeccmax) can be determined. The main question of the study was whether the AFisomax is a specific and independent parameter of muscle function compared to other maximal forces. In 13 healthy subjects (9 male and 4 female), the maximal voluntary isometric contraction (pre- and post-MVIC), the three AF parameters and the MVIC with a prior concentric contraction (MVICpri-con) of the elbow extensors were measured 4 times on two days. Arithmetic mean (M) and maximal (Max) torques of all force types were analyzed. Regarding the reliability of the AF parameters between days, the mean changes were 0.31–1.98 Nm (0.61%–5.47%, p = 0.175–0.552), the standard errors of measurements (SEM) were 1.29–5.68 Nm (2.53%–15.70%) and the ICCs(3,1) = 0.896–0.996. M and Max of AFisomax, AFmax and pre-MVIC correlated highly (r = 0.85–0.98). The M and Max of AFisomax were significantly lower (6.12–14.93 Nm; p ≤ 0.001–0.009) and more variable between trials (coefficient of variation (CVs) ≥ 21.95%) compared to those of pre-MVIC and AFmax (CVs ≤ 5.4%). The results suggest the novel measuring procedure is suitable to reliably quantify the AF, whereby the presented measurement errors should be taken into consideration. The AFisomax seems to reflect its own strength capacity and should be detected separately. It is suggested its normalization to the MVIC or AFmax could serve as an indicator of a neuromuscular function.
In sports and movement sciences isometric muscle function is usually measured by pushing against a stable resistance. However, subjectively one can hold or push isometrically. Several investigations suggest a distinction of those forms. The aim of this study was to investigate whether these two forms of isometric muscle action can be distinguished by objective parameters in an interpersonal setting. 20 subjects were grouped in 10 same sex pairs, in which one partner should perform the pushing isometric muscle action (PIMA) and the other partner executed the holding isometric muscle action (HIMA). The partners had contact at the distal forearms via an interface, which included a strain gauge and an acceleration sensor. The mechanical oscillations of the triceps brachii (MMGtri) muscle, its tendon (MTGtri) and the abdominal muscle (MMGobl) were recorded by a piezoelectric-sensor-based measurement system. Each partner performed three 15s (80% MVIC) and two fatiguing trials (90% MVIC) during PIMA and HIMA, respectively. Parameters to compare PIMA and HIMA were the mean frequency, the normalized mean amplitude, the amplitude variation, the power in the frequency range of 8 to 15 Hz, a special power-frequency ratio and the number of task failures during HIMA or PIMA (partner who quit the task). A “HIMA failure” occurred in 85% of trials (p < 0.001). No significant differences between PIMA and HIMA were found for the mean frequency and normalized amplitude. The MMGobl showed significantly higher values of amplitude variation (15s: p = 0.013; fatiguing: p = 0.007) and of power-frequency-ratio (15s: p = 0.040; fatiguing: p = 0.002) during HIMA and a higher power in the range of 8 to 15 Hz during PIMA (15s: p = 0.001; fatiguing: p = 0.011). MMGtri and MTGtri showed no significant differences. Based on the findings it is suggested that a holding and a pushing isometric muscle action can be distinguished objectively, whereby a more complex neural control is assumed for HIMA.
Adaptive Force (AF) reflects the capability of the neuromuscular system to adapt adequately to external forces with the intention of maintaining a position or motion. One specific approach to assessing AF is to measure force and limb position during a pneumatically applied increasing external force. Through this method, the highest (AFmax), the maximal isometric (AFisomax) and the maximal eccentric Adaptive Force (AFeccmax) can be determined. The main question of the study was whether the AFisomax is a specific and independent parameter of muscle function compared to other maximal forces. In 13 healthy subjects (9 male and 4 female), the maximal voluntary isometric contraction (pre- and post-MVIC), the three AF parameters and the MVIC with a prior concentric contraction (MVICpri-con) of the elbow extensors were measured 4 times on two days. Arithmetic mean (M) and maximal (Max) torques of all force types were analyzed. Regarding the reliability of the AF parameters between days, the mean changes were 0.31–1.98 Nm (0.61%–5.47%, p = 0.175–0.552), the standard errors of measurements (SEM) were 1.29–5.68 Nm (2.53%–15.70%) and the ICCs(3,1) = 0.896–0.996. M and Max of AFisomax, AFmax and pre-MVIC correlated highly (r = 0.85–0.98). The M and Max of AFisomax were significantly lower (6.12–14.93 Nm; p ≤ 0.001–0.009) and more variable between trials (coefficient of variation (CVs) ≥ 21.95%) compared to those of pre-MVIC and AFmax (CVs ≤ 5.4%). The results suggest the novel measuring procedure is suitable to reliably quantify the AF, whereby the presented measurement errors should be taken into consideration. The AFisomax seems to reflect its own strength capacity and should be detected separately. It is suggested its normalization to the MVIC or AFmax could serve as an indicator of a neuromuscular function.
In sports and movement sciences isometric muscle function is usually measured by pushing against a stable resistance. However, subjectively one can hold or push isometrically. Several investigations suggest a distinction of those forms. The aim of this study was to investigate whether these two forms of isometric muscle action can be distinguished by objective parameters in an interpersonal setting. 20 subjects were grouped in 10 same sex pairs, in which one partner should perform the pushing isometric muscle action (PIMA) and the other partner executed the holding isometric muscle action (HIMA). The partners had contact at the distal forearms via an interface, which included a strain gauge and an acceleration sensor. The mechanical oscillations of the triceps brachii (MMGtri) muscle, its tendon (MTGtri) and the abdominal muscle (MMGobl) were recorded by a piezoelectric-sensor-based measurement system. Each partner performed three 15s (80% MVIC) and two fatiguing trials (90% MVIC) during PIMA and HIMA, respectively. Parameters to compare PIMA and HIMA were the mean frequency, the normalized mean amplitude, the amplitude variation, the power in the frequency range of 8 to 15 Hz, a special power-frequency ratio and the number of task failures during HIMA or PIMA (partner who quit the task). A “HIMA failure” occurred in 85% of trials (p < 0.001). No significant differences between PIMA and HIMA were found for the mean frequency and normalized amplitude. The MMGobl showed significantly higher values of amplitude variation (15s: p = 0.013; fatiguing: p = 0.007) and of power-frequency-ratio (15s: p = 0.040; fatiguing: p = 0.002) during HIMA and a higher power in the range of 8 to 15 Hz during PIMA (15s: p = 0.001; fatiguing: p = 0.011). MMGtri and MTGtri showed no significant differences. Based on the findings it is suggested that a holding and a pushing isometric muscle action can be distinguished objectively, whereby a more complex neural control is assumed for HIMA.
The spread of shrubs in Namibian savannas raises questions about the resilience of these ecosystems to global change. This makes it necessary to understand the past dynamics of the vegetation, since there is no consensus on whether shrub encroachment is a new phenomenon, nor on its main drivers. However, a lack of long-term vegetation datasets for the region and the scarcity of suitable palaeoecological archives, makes reconstructing past vegetation and land cover of the savannas a challenge.
To help meet this challenge, this study addresses three main research questions: 1) is pollen analysis a suitable tool to reflect the vegetation change associated with shrub encroachment in savanna environments? 2) Does the current encroached landscape correspond to an alternative stable state of savanna vegetation? 3) To what extent do pollen-based quantitative vegetation reconstructions reflect changes in past land cover?
The research focuses on north-central Namibia, where despite being the region most affected by shrub invasion, particularly since the 21st century, little is known about the dynamics of this phenomenon.
Field-based vegetation data were compared with modern pollen data to assess their correspondence in terms of composition and diversity along precipitation and grazing intensity gradients. In addition, two sediment cores from Lake Otjikoto were analysed to reveal changes in vegetation composition that have occurred in the region over the past 170 years and their possible drivers. For this, a multiproxy approach (fossil pollen, sedimentary ancient DNA (sedaDNA), biomarkers, compound specific carbon (δ13C) and deuterium (δD) isotopes, bulk carbon isotopes (δ13Corg), grain size, geochemical properties) was applied at high taxonomic and temporal resolution. REVEALS modelling of the fossil pollen record from Lake Otjikoto was run to quantitatively reconstruct past vegetation cover. For this, we first made pollen productivity estimates (PPE) of the most relevant savanna taxa in the region using the extended R-value model and two pollen dispersal options (Gaussian plume model and Lagrangian stochastic model). The REVEALS-based vegetation reconstruction was then validated using remote sensing-based regional vegetation data.
The results show that modern pollen reflects the composition of the vegetation well, but diversity less well. Interestingly, precipitation and grazing explain a significant amount of the compositional change in the pollen and vegetation spectra. The multiproxy record shows that a state change from open Combretum woodland to encroached Terminalia shrubland can occur over a century, and that the transition between states spans around 80 years and is characterized by a unique vegetation composition. This transition is supported by gradual environmental changes induced by management (i.e. broad-scale logging for the mining industry, selective grazing and reduced fire activity associated with intensified farming) and related land-use change. Derived environmental changes (i.e. reduced soil moisture, reduced grass cover, changes in species composition and competitiveness, reduced fire intensity) may have affected the resilience of Combretum open woodlands, making them more susceptible to change to an encroached state by stochastic events such as consecutive years of precipitation and drought, and by high concentrations of pCO2. We assume that the resulting encroached state was further stabilized by feedback mechanisms that favour the establishment and competitiveness of woody vegetation.
The REVEALS-based quantitative estimates of plant taxa indicate the predominance of a semi-open landscape throughout the 20th century and a reduction in grass cover below 50% since the 21st century associated with the spread of encroacher woody taxa. Cover estimates show a close match with regional vegetation data, providing support for the vegetation dynamics inferred from multiproxy analyses. Reasonable PPEs were made for all woody taxa, but not for Poaceae.
In conclusion, pollen analysis is a suitable tool to reconstruct past vegetation dynamics in savannas. However, because pollen cannot identify grasses beyond family level, a multiproxy approach, particularly the use of sedaDNA, is required. I was able to separate stable encroached states from mere woodland phases, and could identify drivers and speculate about related feedbacks. In addition, the REVEALS-based quantitative vegetation reconstruction clearly reflects the magnitude of the changes in the vegetation cover that occurred during the last 130 years, despite the limitations of some PPEs.
This research provides new insights into pollen-vegetation relationships in savannas and highlights the importance of multiproxy approaches when reconstructing past vegetation dynamics in semi-arid environments. It also provides the first time series with sufficient taxonomic resolution to show changes in vegetation composition during shrub encroachment, as well as the first quantitative reconstruction of past land cover in the region. These results help to identify the different stages in savanna dynamics and can be used to calibrate predictive models of vegetation change, which are highly relevant to land management.
The survey of the prevalence of chronic ankle instability in elite Taiwanese basketball athletes
(2021)
BACKGROUND: Ankle sprains are common in basketball. It could develop into Chronic Ankle Instability (CAI) causing decreased quality of life, functional performance, early osteoarthritis, and increased risk of other injuries. To develop a strategy of CAI prevention, localized epidemiology data and a valid/reliable tool are essential. However, the epidemiological data of CAI is not conclusive from previous studies and the prevalence of CAI in Taiwanese basketball athletes are not clear. In addition, a valid and reliable tool among the Taiwan-Chinese version to evaluate ankle instability is missing.
PURPOSE: The aims were to have an overview of the prevalence of CAI in sports population using a systematic review, to develop a valid and reliable cross-cultural adapted Cumberland Ankle Instability Tool Questionnaire (CAIT) in Taiwan-Chinese (CAIT-TW), and to survey the prevalence of CAI in elite basketball athletes in Taiwan using CAIT-TW.
METHODS: Firstly, a systematic search was conducted. Research articles applying CAI related questionnaires in order to survey the prevalence of CAI were included in the review. Second, the English version of CAIT was translated and cross-culturally adapted into the CAIT-TW. The construct validity, test-retest reliability, internal consistency, and cutoff score of CAIT-TW were evaluated in an athletic population (N=135). Finally, the cross-sectional data of CAI prevalence in 388 elite Taiwanese basketball athletes were presented. Demographics, presence of CAI, and difference of prevalence between gender, different competitive levels and play positions were evaluated.
RESULTS: The prevalence of CAI was 25%, ranging between 7% and 53%. The prevalence of CAI among participants with a history of ankle sprains was 46%, ranging between 9% and 76%. In addition, the cross-cultural adapted CAIT-TW showed a moderate to strong construct validity, an excellent test-retest reliability, a good internal consistency, and a cutoff score of 21.5 for the Taiwanese athletic population. Finally, 26% of Taiwanese basketball athletes had unilateral CAI while 50% of them had bilateral CAI. In addition, women athletes in the investigated cohort had a higher prevalence of CAI than men. There was no difference in prevalence between competitive levels and among play positions.
CONCLUSION: The systematic review shows that the prevalence of CAI has a wide range among included studies. This could be due to the different exclusion criteria, age, sports discipline, or other factors among the included studies. For future studies, standardized criteria to investigate the epidemiology of CAI are required. The CAI epidemiological study should be prospective. Factors affecting the prevalence of CAI ability should be investigated and described. The translated CAIT-TW is a valid and reliable tool to differentiate between stable and unstable ankles in athletes and may further apply for research or daily practice in Taiwan. In the Taiwanese basketball population, CAI is highly prevalent. This might relate to the research method, preexisting ankle instability, and training-related issues. Women showed a higher prevalence of CAI than men. When applying the preventive measure, gender should be taken into consideration.
Background: The relationship between exercise-induced intratendinous blood flow (IBF) and tendon pathology or training exposure is unclear.
Objective: This study investigates the acute effect of running exercise on sonographic detectable IBF in healthy and tendinopathic Achilles tendons (ATs) of runners and recreational participants.
Methods: 48 participants (43 ± 13 years, 176 ± 9 cm, 75 ± 11 kg) performed a standardized submaximal 30-min constant load treadmill run with Doppler ultrasound “Advanced dynamic flow” examinations before (Upre) and 5, 30, 60, and 120 min (U5-U120) afterward. Included were runners (>30 km/week) and recreational participants (<10 km/week) with healthy (Hrun, n = 10; Hrec, n = 15) or tendinopathic (Trun, n = 13; Trec, n = 10) ATs. IBF was assessed by counting number [n] of intratendinous vessels. IBF data are presented descriptively (%, median [minimum to maximum range] for baseline-IBF and IBF-difference post-exercise). Statistical differences for group and time point IBF and IBF changes were analyzed with Friedman and Kruskal-Wallis ANOVA (α = 0.05).
Results: At baseline, IBF was detected in 40% (3 [1–6]) of Hrun, in 53% (4 [1–5]) of Hrec, in 85% (3 [1–25]) of Trun, and 70% (10 [2–30]) of Trec. At U5 IBF responded to exercise in 30% (3 [−1–9]) of Hrun, in 53% (4 [−2–6]) of Hrec, in 70% (4 [−10–10]) of Trun, and in 80% (5 [1–10]) of Trec. While IBF in 80% of healthy responding ATs returned to baseline at U30, IBF remained elevated until U120 in 60% of tendinopathic ATs. Within groups, IBF changes from Upre-U120 were significant for Hrec (p < 0.01), Trun (p = 0.05), and Trec (p < 0.01). Between groups, IBF changes in consecutive examinations were not significantly different (p > 0.05) but IBF-level was significantly higher at all measurement time points in tendinopathic versus healthy ATs (p < 0.05).
Conclusion: Irrespective of training status and tendon pathology, running leads to an immediate increase of IBF in responding tendons. This increase occurs shortly in healthy and prolonged in tendinopathic ATs. Training exposure does not alter IBF occurrence, but IBF level is elevated in tendon pathology. While an immediate exercise-induced IBF increase is a physiological response, prolonged IBF is considered a pathological finding associated with Achilles tendinopathy.
Background
The anterior cruciate ligament (ACL) rupture can lead to impaired knee function. Reconstruction decreases the mechanical instability but might not have an impact on sensorimotor alterations.
Objective
Evaluation of the sensorimotor function measured with the active joint position sense (JPS) test in anterior cruciate ligament (ACL) reconstructed patients compared to the contralateral side and a healthy control group.
Methods
The databases MEDLINE, CINAHL, EMBASE, PEDro, Cochrane Library and SPORTDiscus were systematically searched from origin until April 2020. Studies published in English, German, French, Spanish or Italian language were included. Evaluation of the sensorimotor performance was restricted to the active joint position sense test in ACL reconstructed participants or healthy controls. The Preferred Items for Systematic Reviews and Meta-Analyses guidelines were followed. Study quality was evaluated using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Data was descriptively synthesized.
Results
Ten studies were included after application of the selective criteria. Higher angular deviation, reaching significant difference (p < 0.001) in one study, was shown up to three months after surgery in the affected limb. Six months post-operative significantly less error (p < 0.01) was found in the reconstructed leg compared to the contralateral side and healthy controls. One or more years after ACL reconstruction significant differences were inconsistent along the studies.
Conclusions
Altered sensorimotor function was present after ACL reconstruction. Due to inconsistencies and small magnitudes, clinical relevance might be questionable. JPS testing can be performed in acute injured persons and prospective studies could enhance knowledge of sensorimotor function throughout the rehabilitative processes.
Seed traits matter
(2021)
Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.
Analysis of protrusion dynamics in amoeboid cell motility by means of regularized contour flows
(2021)
Amoeboid cell motility is essential for a wide range of biological processes including wound healing, embryonic morphogenesis, and cancer metastasis. It relies on complex dynamical patterns of cell shape changes that pose long-standing challenges to mathematical modeling and raise a need for automated and reproducible approaches to extract quantitative morphological features from image sequences. Here, we introduce a theoretical framework and a computational method for obtaining smooth representations of the spatiotemporal contour dynamics from stacks of segmented microscopy images. Based on a Gaussian process regression we propose a one-parameter family of regularized contour flows that allows us to continuously track reference points (virtual markers) between successive cell contours. We use this approach to define a coordinate system on the moving cell boundary and to represent different local geometric quantities in this frame of reference. In particular, we introduce the local marker dispersion as a measure to identify localized membrane expansions and provide a fully automated way to extract the properties of such expansions, including their area and growth time. The methods are available as an open-source software package called AmoePy, a Python-based toolbox for analyzing amoeboid cell motility (based on time-lapse microscopy data), including a graphical user interface and detailed documentation. Due to the mathematical rigor of our framework, we envision it to be of use for the development of novel cell motility models. We mainly use experimental data of the social amoeba Dictyostelium discoideum to illustrate and validate our approach. <br /> Author summary Amoeboid motion is a crawling-like cell migration that plays an important key role in multiple biological processes such as wound healing and cancer metastasis. This type of cell motility results from expanding and simultaneously contracting parts of the cell membrane. From fluorescence images, we obtain a sequence of points, representing the cell membrane, for each time step. By using regression analysis on these sequences, we derive smooth representations, so-called contours, of the membrane. Since the number of measurements is discrete and often limited, the question is raised of how to link consecutive contours with each other. In this work, we present a novel mathematical framework in which these links are described by regularized flows allowing a certain degree of concentration or stretching of neighboring reference points on the same contour. This stretching rate, the so-called local dispersion, is used to identify expansions and contractions of the cell membrane providing a fully automated way of extracting properties of these cell shape changes. We applied our methods to time-lapse microscopy data of the social amoeba Dictyostelium discoideum.
In this study, we reassessed the taxonomic position of Typhlomys (Rodentia: Platacanthomyidae) from Huangshan, Anhui, China, based on morphological and molecular evidence. Results suggested that Typhlomys is comprised of up to six species, including four currently recognized species ( Typhlomys cinereus, T. chapensis, T. daloushanensis, and T. nanus), one unconfirmed candidate species, and one new species ( Typhlomys huangshanensis sp. nov.). Morphological analyses further supported the designation of the Huangshan specimens found at mid-elevations in the southern Huangshan Mountains (600 m to 1 200 m a.s.l.) as a new species.
The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson’s disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.
forum:logopädie 35.2021, 1
(2021)
Permafrost is warming globally, which leads to widespread permafrost thaw and impacts the surrounding landscapes, ecosystems and infrastructure. Especially ice-rich permafrost is vulnerable to rapid and abrupt thaw, resulting from the melting of excess ground ice. Local remote sensing studies have detected increasing rates of abrupt permafrost disturbances, such as thermokarst lake change and drainage, coastal erosion and RTS in the last two decades. All of which indicate an acceleration of permafrost degradation.
In particular retrogressive thaw slumps (RTS) are abrupt disturbances that expand by up to several meters each year and impact local and regional topographic gradients, hydrological pathways, sediment and nutrient mobilisation into aquatic systems, and increased permafrost carbon mobilisation. The feedback between abrupt permafrost thaw and the carbon cycle is a crucial component of the Earth system and a relevant driver in global climate models. However, an assessment of RTS at high temporal resolution to determine the dynamic thaw processes and identify the main thaw drivers as well as a continental-scale assessment across diverse permafrost regions are still lacking.
In northern high latitudes optical remote sensing is restricted by environmental factors and frequent cloud coverage. This decreases image availability and thus constrains the application of automated algorithms for time series disturbance detection for large-scale abrupt permafrost disturbances at high temporal resolution. Since models and observations suggest that abrupt permafrost disturbances will intensify, we require disturbance products at continental-scale, which allow for meaningful integration into Earth system models.
The main aim of this dissertation therefore, is to enhance our knowledge on the spatial extent and temporal dynamics of abrupt permafrost disturbances in a large-scale assessment. To address this, three research objectives were posed:
1. Assess the comparability and compatibility of Landsat-8 and Sentinel-2 data for a combined use in multi-spectral analysis in northern high latitudes.
2. Adapt an image mosaicking method for Landsat and Sentinel-2 data to create combined mosaics of high quality as input for high temporal disturbance assessments in northern high latitudes.
3. Automatically map retrogressive thaw slumps on the landscape-scale and assess their high temporal thaw dynamics.
We assessed the comparability of Landsat-8 and Sentinel-2 imagery by spectral comparison of corresponding bands. Based on overlapping same-day acquisitions of Landsat-8 and Sentinel-2 we derived spectral bandpass adjustment coefficients for North Siberia to adjust Sentinel-2 reflectance values to resemble Landsat-8 and harmonise the two data sets. Furthermore, we adapted a workflow to combine Landsat and Sentinel-2 images to create homogeneous and gap-free annual mosaics. We determined the number of images and cloud-free pixels, the spatial coverage and the quality of the mosaic with spectral comparisons to demonstrate the relevance of the Landsat+Sentinel-2 mosaics. Lastly, we adapted the automatic disturbance detection algorithm LandTrendr for large-scale RTS identification and mapping at high temporal resolution. For this, we modified the temporal segmentation algorithm for annual gradual and abrupt disturbance detection to incorporate the annual Landsat+Sentinel-2 mosaics. We further parametrised the temporal segmentation and spectral filtering for optimised RTS detection, conducted further spatial masking and filtering, and implemented a binary object classification algorithm with machine-learning to derive RTS from the LandTrendr disturbance output. We applied the algorithm to North Siberia, covering an area of 8.1 x 106 km2.
The spectral band comparison between same-day Landsat-8 and Sentinel-2 acquisitions already showed an overall good fit between both satellite products. However, applying the acquired spectral bandpass coefficients for adjustment of Sentinel-2 reflectance values, resulted in a near-perfect alignment between the same-day images. It can therefore be concluded that the spectral band adjustment succeeds in adjusting Sentinel-2 spectral values to those of Landsat-8 in North Siberia.
The number of available cloud-free images increased steadily between 1999 and 2019, especially intensified after 2016 with the addition of Sentinel-2 images. This signifies a highly improved input database for the mosaicking workflow. In a comparison of annual mosaics, the Landsat+Sentinel-2 mosaics always fully covered the study areas, while Landsat-only mosaics contained data-gaps for the same years. The spectral comparison of input images and Landsat+Sentinel-2 mosaic showed a high correlation between the input images and the mosaic bands, testifying mosaicking results of high quality. Our results show that especially the mosaic coverage for northern, coastal areas was substantially improved with the Landsat+Sentinel-2 mosaics. By combining data from both Landsat and Sentinel-2 sensors we reliably created input mosaics at high spatial resolution for comprehensive time series analyses.
This research presents the first automatically derived assessment of RTS distribution and temporal dynamics at continental-scale. In total, we identified 50,895 RTS, primarily located in ice-rich permafrost regions, as well as a steady increase in RTS-affected areas between 2001 and 2019 across North Siberia. From 2016 onward the RTS area increased more abruptly, indicating heightened thaw slump dynamics in this period. Overall, the RTS-affected area increased by 331 % within the observation period. Contrary to this, five focus sites show spatiotemporal variability in their annual RTS dynamics, alternating between periods of increased and decreased RTS development. This suggests a close relationship to varying thaw drivers. The majority of identified RTS was active from 2000 onward and only a small proportion initiated during the assessment period. This highlights that the increase in RTS-affected area was mainly caused by enlarging existing RTS and not by newly initiated RTS.
Overall, this research showed the advantages of combining Landsat and Sentinel-2 data in northern high latitudes and the improvements in spatial and temporal coverage of combined annual mosaics. The mosaics build the database for automated disturbance detection to reliably map RTS and other abrupt permafrost disturbances at continental-scale. The assessment at high temporal resolution further testifies the increasing impact of abrupt permafrost disturbances and likewise emphasises the spatio-temporal variability of thaw dynamics across landscapes. Obtaining such consistent disturbance products is necessary to parametrise regional and global climate change models, for enabling an improved representation of the permafrost thaw feedback.
The Arctic is greatly impacted by climate change. The increase in air temperature drives the thawing of permafrost and an increase in coastal erosion and river discharge. This leads to a greater input of sediment and organic matter into coastal waters, which substantially impacts the ecosystems by reducing light transmission through the water column and altering the biogeochemistry, but also the subsistence economy of local people, and changes in climate because of the transformation of organic matter into greenhouse gases. Yet, the quantification of suspended sediment in Arctic coastal and nearshore waters remains unsatisfactory due to the absence of dedicated algorithms to resolve the high loads occurring in the close vicinity of the shoreline. In this study we present the Arctic Nearshore Turbidity Algorithm (ANTA), the first reflectance-turbidity relationship specifically targeted towards Arctic nearshore waters that is tuned with in-situ measurements from the nearshore waters of Herschel Island Qikiqtaruk in the western Canadian Arctic. A semi-empirical model was calibrated for several relevant sensors in ocean color remote sensing, including MODIS, Sentinel 3 (OLCI), Landsat 8 (OLI), and Sentinel 2 (MSI), as well as the older Landsat sensors TM and ETM+. The ANTA performed better with Landsat 8 than with Sentinel 2 and Sentinel 3. The application of the ANTA to Sentinel 2 imagery that matches in-situ turbidity samples taken in Adventfjorden, Svalbard, shows transferability to nearshore areas beyond Herschel Island Qikiqtaruk.
Der Zugang zu einem Asylverfahren in der EU ist ein umkämpftes soziales Gut. Die Studie zeichnet ein komplexes Bild von Ausschließungs- und Usurpationsstrategien im Feld der europäischen und speziell der italienischen und deutschen Asylverwaltung zwischen 2015 und 2018. (Supra-)nationale Verwaltungs- und Vollzugsorganisationen versuchen Flüchtende von dem Verwaltungsakt abzuhalten und entwickeln territoriale und administrative Exklusionsstrategien, um Fluchtmobilität und Asyl zu verwehren. Gleichzeitig erkämpfen Seenotrettungs- und Kirchenorganisationen den Zugang zum Asylverfahren, indem sie sich mit Flüchtenden solidarisieren und diesen eine Partizipation an öffentlichen Gütern und Rechten der Aufnahmegesellschaft ermöglichen. Für Flüchtende wird der formale Zugang zu und die temporäre Mitgliedschaft in einer Aufnahmegesellschaft in konfliktreichen und inter-organisationalen Entscheidungen ausgehandelt. Die formale Organisation wird zum Ort der Schließungskämpfe, indemsie als Schließungsakteur und zwischengesellschaftliches Schließungssystem formale Interaktionen zwischen Geflüchteten und Aufnahmegesellschaft ermöglicht oder verhindert. Die Synthese von schließungs- und organisationstheoretischen Perspektiven trägt dazu bei, dass gesellschaftliche Ordnungsbildung organisationssoziologisch erklärbar wird.
Mental health problems remain among the main generators of costs within and beyond the health care system. Psychotherapy, the tool of choice in their treatment, is qualified by social interaction, and cooperation within the therapist-patient-dyad. Research into the factors influencing therapy success to date is neither exhaustive nor conclusive. Among many others, the quality of the relationship between therapist and patient stands out regardless of the followed psychotherapy school. Emerging research points to a connection between interpersonal synchronization within the sessions and therapy outcome. Consequently, it can be considered significant for the shaping of this relationship. The framework of Embodied Cognition assumes bodily and neuronal correlates of thinking. Therefore, the present paper reviews investigations on interpersonal, non-verbal synchrony in two domains: firstly, studies on interpersonal synchrony in psychotherapy are reviewed (synchronization of movement). Secondly, findings on neurological correlates of interpersonal synchrony (assessed with EEG, fMRI, fNIRS) are summarized in a narrative manner. In addition, the question is asked whether interpersonal synchrony can be achieved voluntarily on an individual level. It is concluded that there might be mechanisms which could give more insights into therapy success, but as of yet remain uninvestigated. Further, the framework of embodied cognition applies more to the current body of evidence than classical cognitivist views. Nevertheless, deeper research into interpersonal physical and neurological processes utilizing the framework of Embodied Cognition emerges as a possible route of investigation on the road to lower drop-out rates, improved and quality-controlled therapeutic interventions, thereby significantly reducing healthcare costs.
Mental health problems remain among the main generators of costs within and beyond the health care system. Psychotherapy, the tool of choice in their treatment, is qualified by social interaction, and cooperation within the therapist-patient-dyad. Research into the factors influencing therapy success to date is neither exhaustive nor conclusive. Among many others, the quality of the relationship between therapist and patient stands out regardless of the followed psychotherapy school. Emerging research points to a connection between interpersonal synchronization within the sessions and therapy outcome. Consequently, it can be considered significant for the shaping of this relationship. The framework of Embodied Cognition assumes bodily and neuronal correlates of thinking. Therefore, the present paper reviews investigations on interpersonal, non-verbal synchrony in two domains: firstly, studies on interpersonal synchrony in psychotherapy are reviewed (synchronization of movement). Secondly, findings on neurological correlates of interpersonal synchrony (assessed with EEG, fMRI, fNIRS) are summarized in a narrative manner. In addition, the question is asked whether interpersonal synchrony can be achieved voluntarily on an individual level. It is concluded that there might be mechanisms which could give more insights into therapy success, but as of yet remain uninvestigated. Further, the framework of embodied cognition applies more to the current body of evidence than classical cognitivist views. Nevertheless, deeper research into interpersonal physical and neurological processes utilizing the framework of Embodied Cognition emerges as a possible route of investigation on the road to lower drop-out rates, improved and quality-controlled therapeutic interventions, thereby significantly reducing healthcare costs.
The present work deals with the variation in the linearisation of German infinitival complements from a diachronic perspective. Based on the observation that in present-day German the position of infinitival complements is restricted by properties of the matrix verb (Haider, 2010, Wurmbrand, 2001), whereas this appears much more liberal in older stages of German (Demske, 2008, Maché and Abraham, 2011, Demske, 2015), this dissertation investigates the emergence of those restrictions and the factors that have led to a reduced, yet still existing variability. The study contrasts infinitival complements of two types of matrix verbs, namely raising and control verbs. In present-day German, these show different syntactic behaviour and opposite preferences as far as the position of the infinitive is concerned: while infinitival complements of raising verbs build a single clausal domain with the with the matrix verb and occur obligatorily intraposed, infinitive complements of control verbs can form clausal constituents and occur predominantly extraposed. This correlation is not attested in older stages of German, at least not until Early New High German.
Drawing on diachronic corpus data, the present work provides a description of the changes in the linearisation of infinitival complements from Early New High German to present-day German which aims at finding out when the correlation between infinitive type and word order emerged and further examines their possible causes. The study shows that word order change in German infinitival complements is not a case of syntactic change in the narrow sense, but that the diachronic variation results from the interaction of different language-internal and language-external factors and that it reflects, on the one hand, the influence of language modality on the emerging standard language and, on the other hand, a process of specialisation.
The regulation of oxygen and blood supply during isometric muscle actions is still unclear. Recently, two behavioral types of oxygen saturation (SvO2) and relative hemoglobin amount (rHb) in venous microvessels were described during a fatiguing holding isometric muscle action (HIMA) (type I: nearly parallel behavior of SvO2 and rHb; type II: partly inverse behavior). The study aimed to ascertain an explanation of these two regulative behaviors. Twelve subjects performed one fatiguing HIMA trial with each arm by weight holding at 60% of the maximal voluntary isometric contraction (MVIC) in a 90° elbow flexion. Six subjects additionally executed one fatiguing PIMA trial by pulling on an immovable resistance with 60% of the MVIC with each side and same position. Both regulative types mentioned were found during HIMA (I: n = 7, II: n = 17) and PIMA (I: n = 3, II: n = 9). During the fatiguing measurements, rHb decreased initially and started to increase in type II at an average SvO2-level of 58.75 ± 2.14%. In type I, SvO2 never reached that specific value during loading. This might indicate the existence of a threshold around 59% which seems to trigger the increase in rHb and could explain the two behavioral types. An approach is discussed to meet the apparent incompatibility of an increased capillary blood filling (rHb) despite high intramuscular pressures which were found by other research groups during isometric muscle actions.
The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson’s disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.
The regulation of oxygen and blood supply during isometric muscle actions is still unclear. Recently, two behavioral types of oxygen saturation (SvO2) and relative hemoglobin amount (rHb) in venous microvessels were described during a fatiguing holding isometric muscle action (HIMA) (type I: nearly parallel behavior of SvO2 and rHb; type II: partly inverse behavior). The study aimed to ascertain an explanation of these two regulative behaviors. Twelve subjects performed one fatiguing HIMA trial with each arm by weight holding at 60% of the maximal voluntary isometric contraction (MVIC) in a 90° elbow flexion. Six subjects additionally executed one fatiguing PIMA trial by pulling on an immovable resistance with 60% of the MVIC with each side and same position. Both regulative types mentioned were found during HIMA (I: n = 7, II: n = 17) and PIMA (I: n = 3, II: n = 9). During the fatiguing measurements, rHb decreased initially and started to increase in type II at an average SvO2-level of 58.75 ± 2.14%. In type I, SvO2 never reached that specific value during loading. This might indicate the existence of a threshold around 59% which seems to trigger the increase in rHb and could explain the two behavioral types. An approach is discussed to meet the apparent incompatibility of an increased capillary blood filling (rHb) despite high intramuscular pressures which were found by other research groups during isometric muscle actions.
Seed traits matter
(2021)
Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.
The effects of exercise interventions on unspecific chronic low back pain (CLBP) have been investigated in many studies, but the results are inconclusive regarding exercise types, efficiency, and sustainability. This may be because the influence of psychosocial factors on exercise induced adaptation regarding CLBP is neglected. Therefore, this study assessed psychosocial characteristics, which moderate and mediate the effects of sensorimotor exercise on LBP. A single-blind 3-arm multicenter randomized controlled trial was conducted for 12-weeks. Three exercise groups, sensorimotor exercise (SMT), sensorimotor and behavioral training (SMT-BT), and regular routines (CG) were randomly assigned to 662 volunteers. Primary outcomes (pain intensity and disability) and psychosocial characteristics were assessed at baseline (M1) and follow-up (3/6/12/24 weeks, M2-M5). Multiple regression models were used to analyze whether psychosocial characteristics are moderators of the relationship between exercise and pain, meaning that psychosocial factors and exercise interact. Causal mediation analysis were conducted to analyze, whether psychosocial characteristics mediate the exercise effect on pain. A total of 453 participants with intermittent pain (mean age = 39.5 ± 12.2 years, f = 62%) completed the training. It was shown, that depressive symptomatology (at M4, M5), vital exhaustion (at M4), and perceived social support (at M5) are significant moderators of the relationship between exercise and the reduction of pain intensity. Further depressive mood (at M4), social-satisfaction (at M4), and anxiety (at M5 SMT) significantly moderate the exercise effect on pain disability. The amount of moderation was of clinical relevance. In contrast, there were no psychosocial variables which mediated exercise effects on pain. In conclusion it was shown, that psychosocial variables can be moderators in the relationship between sensorimotor exercise induced adaptation on CLBP which may explain conflicting results in the past regarding the merit of exercise interventions in CLBP. Results suggest further an early identification of psychosocial risk factors by diagnostic tools, which may essential support the planning of personalized exercise therapy.
Level of Evidence: Level I.
Clinical Trial Registration: DRKS00004977, LOE: I, MiSpEx: grant-number: 080102A/11-14. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00004977.
Objective: This study investigated intraindividual differences of intratendinous blood flow (IBF) in response to running exercise in participants with Achilles tendinopathy.
Design: This is a cross-sectional study.
Setting: The study was conducted at the University Outpatient Clinic.
Participants: Sonographic detectable intratendinous blood flow was examined in symptomatic and contralateral asymptomatic Achilles tendons of 19 participants (42 ± 13 years, 178 ± 10 cm, 76 ± 12 kg, VISA-A 75 ± 16) with clinically diagnosed unilateral Achilles tendinopathy and sonographic evident tendinosis.
Intervention: IBF was assessed using Doppler ultrasound “Advanced Dynamic Flow” before (Upre) and 5, 30, 60, and 120 min (U5–U120) after a standardized submaximal constant load run.
Main Outcome Measure: IBF was quantified by counting the number (n) of vessels in each tendon.
Results: At Upre, IBF was higher in symptomatic compared with asymptomatic tendons [mean 6.3 (95% CI: 2.8–9.9) and 1.7 (0.4–2.9), p < 0.01]. Overall, 63% of symptomatic and 47% of asymptomatic Achilles tendons responded to exercise, whereas 16 and 11% showed persisting IBF and 21 and 42% remained avascular throughout the investigation. At U5, IBF increased in both symptomatic and asymptomatic tendons [difference to baseline: 2.4 (0.3–4.5) and 0.9 (0.5–1.4), p = 0.05]. At U30 to U120, IBF was still increased in symptomatic but not in asymptomatic tendons [mean difference to baseline: 1.9 (0.8–2.9) and 0.1 (-0.9 to 1.2), p < 0.01].
Conclusion: Irrespective of pathology, 47–63% of Achilles tendons responded to exercise with an immediate acute physiological IBF increase by an average of one to two vessels (“responders”). A higher amount of baseline IBF (approximately five vessels) and a prolonged exercise-induced IBF response found in symptomatic ATs indicate a pain-associated altered intratendinous “neovascularization.”
Eccentric exercise is discussed as a treatment option for clinical populations, but specific responses in terms of muscle damage and systemic inflammation after repeated loading of large muscle groups have not been conclusively characterized. Therefore, this study tested the feasibility of an isokinetic protocol for repeated maximum eccentric loading of the trunk muscles. Nine asymptomatic participants (5 f/4 m; 34±6 yrs; 175±13 cm; 76±17 kg) performed three isokinetic 2-minute all-out trunk strength tests (1x concentric (CON), 2x eccentric (ECC1, ECC2), 2 weeks apart; flexion/extension, 60°/s, ROM 55°). Outcomes were peak torque, torque decline, total work, and indicators of muscle damage and inflammation (over 168 h). Statistics were done using the Friedman test (Dunn’s post-test). For ECC1 and ECC2, peak torque and total work were increased and torque decline reduced compared to CON. Repeated ECC bouts yielded unaltered torque and work outcomes. Muscle damage markers were highest after ECC1 (soreness 48 h, creatine kinase 72 h; p<0.05). Their overall responses (area under the curve) were abolished post-ECC2 compared to post-ECC1 (p<0.05). Interleukin-6 was higher post-ECC1 than CON, and attenuated post-ECC2 (p>0.05). Interleukin-10 and tumor necrosis factor-α were not detectable. All markers showed high inter-individual variability. The protocol was feasible to induce muscle damage indicators after exercising a large muscle group, but the pilot results indicated only weak systemic inflammatory responses in asymptomatic adults.
Das Therapiemanagement bei Lipödem stellt auf Grund unzureichenden Wissensstandes in entscheidenden Aspekten eine besondere Herausforderung dar. Da die Pathogenese der Erkrankung nicht hinreichend geklärt ist und bislang kein pathognomonisches Diagnostikkriterium definiert wurde, beklagen viele Betroffene einen langjährigen Leidensweg bis zur Einleitung von Therapiemaßnahmen. Durch Steigerung der Awareness der Erkrankung in den letzten Jahren konnten die Intervalle bis zur korrekten Diagnose erfreulicherweise erheblich verkürzt werden. Obwohl die Zuordnung der Beschwerden zu einer klar definierten Erkrankung für viele Patientinnen eine Erleichterung ist, stellt die Erkenntnis über begrenzte Therapiemöglichkeiten häufig eine neuerliche Belastung dar.
Als Konsequenz der ungeklärten Pathogenese konnte bis dato keine kausale Therapie für das Lipödem definiert werden. Zu Beginn waren die Möglichkeiten konservativer Behandlungsstrategien nur eingeschränkt in den Rahmen eines allgemeingültigen Konzeptes involviert und insbesondere Limitationen nicht klar definiert. Obwohl in diversen Bereichen der Therapie weiterhin keine ausreichende Evidenz besteht, konnten durch eine systematische Aufarbeitung die grundsätzlichen Behandlungsoptionen in Relation zueinander gesetzt werden. Betroffene Patientinnen, sowie die verschiedenen in die Behandlung integrierte medizinische Disziplinen verfügen somit über einen grundsätzlichen Handlungsalgorithmus, deren Empfehlungen über einfache Rezeptierung von Lymphdrainage und Kompressionsbekleidung hinausgehen. Durch kritische Reflexion der geltenden Dogmata wurde ein interdisziplinärer Leitfaden vorgeschlagen, der auf nachvollziehbare Weise im Sinne eines Stufenschemas alle wesentlichen Therapiesäulen in einen allgemeingültigen Behandlungsplan einbindet.
Im vielschichten Management der Erkrankung verbleibt die operative Behandlung, die Liposuktion, allerdings häufig als „ultima ratio“ nach ausbleibender Linderung unter konservativen Therapiemaßnahmen. Die wesentliche Zielstellung der vorliegenden Arbeit konzentriert sich demnach auf die Optimierung des operativen Vorgehens in der Durchführung von Liposuktionen bei Patientinnen mit Lipödem und zeigt sowohl Grenzen der Indikationsstellung, als auch Potenzial des Behandlungserfolges im Langzeitverlauf auf. Langzeitergebnisse zeigen, dass die Liposuktion als sicherer Eingriff mit dem Potenzial einer nachhaltigen Symptomreduktion für Lipödem-Patientinnen angesehen werden kann. Betont werden soll zudem die Notwendigkeit der Verzahnung operativer Maßnahmen mit konservativen Therapien und somit die Integration der Liposuktion als sinnvolle Behandlungsalternative in ein klar umrissenes Therapiekonzept.
Methodisch greift die Arbeit auf insgesamt 10 Publikationen zurück. Die hier postulierte mehrzeitige Megaliposuktion zur Therapie des Lipödems, mit summierten Gesamtaspirationsvolumina über alle Eingriffe von bis zu 66.000 ml, konnte als evidenzbasiertes Therapieverfahren bestätigt und validiert werden. Die beschriebenen niedrigen Komplikationsraten sind unter Anderem Resultat einer differenzierten, individualisierten perioperativen Strategie. Neben der Berücksichtigung grundsätzlicher methodischer Prinzipien existieren allerdings vielfältige Variationen, deren Implikationen auf Komplikationsraten jeweils differenziert zu betrachten sind. Es existiert zwar kein Konsensus für ein allgemeingültiges Standardverfahren der Liposuktion, allerdings konnten zahlreiche Elemente im perioperativen Management definiert werden, die unabhängig von der verwendeten Operationstechnik einen potenziellen positiven Einfluss auf das Outcome haben. Obwohl die Liposuktion bei Lipödem somit zusammenfassend mittlerweile als sicheres Verfahren gelten kann, sind einige Aspekte weiterhin nicht abschließend geklärt. Hierbei stehen vor allem das Volumenmanagement und die standardisierte Festlegung des maximalen Aspirationsvolumens im Fokus.
Die Analyse verschiedener Kovariablen auf die Linderung Lipödem-assoziierter Symptome nach Liposuktion zeigt, dass Alter, Body-Mass-Index (BMI) und präoperatives Stadium der Erkrankung einen signifikanten Einfluss auf das postoperative Ergebnis haben und in der Planung des mehrzeitigen operativen Vorgehens berücksichtigt werden müssen. BMI- oder körpergewichtsabhängige Zielgrößen der Absaugvolumina waren als Prognosefaktor für das postoperative Outcome dagegen nicht relevant. Inwieweit dies möglicherweise an der Überschreitung des „notwendigen“ Volumengrenzwerts für adäquate Symptomlinderung durch reguläre Durchführung von Megaliposuktionen liegen könnte, oder ob dieser Parameter tatsächlich keinen Einfluss auf das Ergebnis nach Operation besitzt, konnte nicht abschließend geklärt werden.
Weiterhin konnte ein positiver Nutzen auf assoziierte Begleiterkrankungen bei Lipödem nachgewiesen werden. Das Spektrum der Behandlungsmethoden kann durch reguläre Integration der Liposuktion in das Therapieschema somit um eine nachhaltige Alternative sinnvoll ergänzt werden. Im Unterschied zur alleinigen konservativen Therapie kann hierdurch ein wesentlicher Schritt weg von der alleinigen symptomatischen Therapie gemacht werden. Zudem die vielfältige Symptomatik der diversen assoziierten Komorbiditäten zu berücksichtigen. Als Konsequenz und für die Notwendigkeit eines ganzheitlichen, interdisziplinären Therapieansatzes wäre der Terminus „Lipödem-Syndrom“ möglicherweise treffender und wird zur Diskussion gestellt.
Für ein gesondertes Patientenklientel wurden zudem basale Grundsätze im perioperativen Vorgehen differenziert aufgearbeitet. Lipödem-Patientinnen mit begleitendem von-Willebrand-Syndrom stellen im Hinblick auf Blutungskomplikationen eine außerordentliche Herausforderung dar. Die vorliegenden evidenzbasierten Empfehlungen zum Therapiemanagement dieser Patientinnen bei Eingriffen ähnlicher Risikoklassifizierung wurden systematisch aufgearbeitet und in Bezug zu den speziellen Anforderungen bei Megaliposuktionen gebracht. Das dabei erarbeitete Therapieschema wird die präoperative Detektion von Koagulopathien im Allgemeinen, sowie die perioperative Komplikationsrate bei von-Willebrand-Patientinnen im Speziellen zukünftig erheblich verbessern.
Zusammenfassend konnte somit ein allgemeingültiger Algorithmus für die moderne und langfristig erfolgreiche Therapie von Lipödem-Patientinnen mit besonderem Fokus auf die Megaliposuktion erarbeitet werden. Bei adäquatem perioperativem Management und Berücksichtigung der großen Volumenverschiebungen kann der Eingriff komplikationsarm und sicher durchgeführt werden. Nicht abschließend geklärt ist derzeit die Pathophysiologie der Erkrankung wobei eine immunologische Genese sowie die primäre Pathologie des Lymphgefäßsystems bzw. der Fett(vorläufer)zellen als Erklärungmodelle favorisiert werden. Die Entwicklung diagnostischer Biomarker sollte dabei verfolgt werden.
Enhanced charge selectivity via anodic-C60 layer reduces nonradiative losses in organic solar cells
(2021)
Interfacial layers in conjunction with suitable charge-transport layers can significantly improve the performance of optoelectronic devices by facilitating efficient charge carrier injection and extraction.
This work uses a neat C-60 interlayer on the anode to experimentally reveal that surface recombination is a significant contributor to nonradiative recombination losses in organic solar cells.
These losses are shown to proportionally increase with the extent of contact between donor molecules in the photoactive layer and a molybdenum oxide (MoO3) hole extraction layer, proven by calculating voltage losses in low- and high-donor-content bulk heterojunction device architectures.
Using a novel in-device determination of the built-in voltage, the suppression of surface recombination, due to the insertion of a thin anodic-C-60 interlayer on MoO3, is attributed to an enhanced built-in potential.
The increased built-in voltage reduces the presence of minority charge carriers at the electrodes-a new perspective on the principle of selective charge extraction layers.
The benefit to device efficiency is limited by a critical interlayer thickness, which depends on the donor material in bilayer devices.
Given the high popularity of MoO3 as an efficient hole extraction and injection layer and the increasingly popular discussion on interfacial phenomena in organic optoelectronic devices, these findings are relevant to and address different branches of organic electronics, providing insights for future device design.
Starch is a natural storage carbohydrate in plants and algae. It consists of two relatively simple homo-biopolymers, amylopectin and amylose, with only alpha-1,4 and alpha-1,6 linked glucosyl units. Starch is an essential source of nutrition and animal food, as well as an important raw material for industry. However, despite increasing knowledge, detailed information about its structure and turnover are largely lacking. In the last decades, most data were generated using bulk experiments, a method which obviously presents limitations regarding a deeper understanding of the starch metabolism. Here, we discuss some unavoidable questions arising from the existing data. We focus on a few examples related to starch biosynthesis, degradation, and structure where these limitations strongly emerge. Closing these knowledge gaps will also be extremely important for taking the necessary steps in order to set up starch-providing crops for the challenges of the ongoing climate changes, as well as for increasing the usability of starches for industrial applications by biotechnology.
Das Gewichtsstigma und insbesondere das internalisierte Gewichtsstigma sind bei Kindern und Jugendlichen mit negativen Folgen für die physische und psychische Gesundheit assoziiert. Da die Befundlage in diesem Altersbereich jedoch noch unzureichend ist, war es das Ziel der Dissertation, begünstigende Faktoren und Folgen von gewichtsbezogener Stigmatisierung und internalisiertem Gewichtsstigma bei Kindern und Jugendlichen zu untersuchen. Die Analysen basierten auf zwei großen Stichproben, die im Rahmen der prospektiven PIER-Studie an Schulen rekrutiert wurden. Die erste Publikation bezieht sich auf eine Stichprobe mit Kindern und Jugendlichen im Alter zwischen 9 und 19 Jahren (49.2 % weiblich) und untersuchte den prospektiven bidirektionalen Zusammenhang zwischen erlebter Gewichtsstigmatisierung und Gewichtsstatus anhand eines latenten Strukturgleichungsmodells über drei Messzeitpunkte hinweg. Die anderen beiden Publikationen beziehen sich auf eine Stichprobe mit Kindern und Jugendlichen im Alter zwischen 6 und 11 Jahren (51.1 % weiblich). Die zweite Publikation analysierte anhand einer hierarchischen Regression, welche intrapersonalen Risikofaktoren das internalisierte Gewichtsstigma prospektiv prädizieren. Die dritte Publikation untersuchte anhand von ROC-Kurven, ab welchem Ausmaß das internalisierte Gewichtsstigma mit einem erhöhten Risiko für psychosoziale Auffälligkeit und gestörtes Essverhalten einhergeht. Im Rahmen der ersten Publikation zeigte sich, dass ein höherer Gewichtsstatus mit einer höheren späteren Gewichtsstigmatisierung einhergeht und umgekehrt die Gewichtsstigmatisierung auch den späteren Gewichtsstatus prädiziert. Die zweite Publikation identifizierte Gewichtsstatus, gewichtsbezogene Hänseleien, depressive Symptome, Körperunzufriedenheit, Relevanz der eigenen Figur sowie das weibliche Geschlecht und einen niedrigeren Bildungsabschluss der Eltern als Prädiktoren des internalisierten Gewichtsstigmas. Die dritte Publikation verdeutlichte, dass das internalisierte Gewichtsstigma bereits ab einem geringen Ausmaß mit einem erhöhten Risiko für gestörtes Essverhalten einhergeht und mit weiteren psychosozialen Problemen assoziiert ist. Insgesamt zeigte sich, dass sowohl das erlebte als auch das internalisierte Gewichtsstigma bei Kindern und Jugendlichen über alle Gewichtsgruppen hinweg relevante Konstrukte sind, die im Entwicklungsverlauf ein komplexes Gefüge bilden. Es wurde deutlich, dass es essentiell ist, bidirektionale Wirkmechanismen einzubeziehen. Die vorliegende Dissertation liefert erste Ansatzpunkte für die Gestaltung von Präventions- und Interventionsmaßnahmen, um ungünstige Entwicklungsverläufe in Folge von Gewichtsstigmatisierung und internalisiertem Gewichtsstigma zu verhindern.
Background: Aggression-related sexual fantasies (ASF) are considered an important risk factor for sexual aggression, but empirical knowledge is limited, in part because previous research has been based on predominantly male, North-American college samples, and limited numbers of questions. <br /> Aim: The present study aimed to foster the knowledge about the frequency and correlates of ASF, while including a large sample of women and a broad range of ASF. <br /> Method: A convenience sample of N = 664 participants from Germany including 508 (77%) women and 156 (23%) men with a median age of 25 (21-27) years answered an online questionnaire. Participants were mainly recruited via social networks (online and in person) and were mainly students. We examined the frequencies of (aggression-related) sexual fantasies and their expected factor structure (factors reflecting affective, experimental, masochistic, and aggression-related contents) via exploratory factor analysis. We investigated potential correlates (eg, psychopathic traits, attitudes towards sexual fantasies) as predictors of ASF using multiple regression analyses. Finally, we examined whether ASF would positively predict sexual aggression beyond other pertinent risk factors using multiple regression analysis. <br /> Outcomes: The participants rated the frequency of a broad set of 56 aggression-related and other sexual fantasies, attitudes towards sexual fantasies, the Big Five (ie, broad personality dimensions including neuroticism and extraversion), sexual aggression, and other risk factors for sexual aggression. <br /> Results: All participants reported non-aggression-related sexual fantasies and 77% reported at least one ASF in their lives. Being male, frequent sexual fantasies, psychopathic traits, and negative attitudes towards sexual fantasies predicted more frequent ASF. ASF were the strongest predictor of sexual aggression beyond other risk factors, including general aggression, psychopathic traits, rape myth acceptance, and violent pornography consumption. <br /> Clinical Translation: ASF may be an important risk factor for sexual aggression and should be more strongly considered in prevention and intervention efforts. <br /> Strengths and Limitations: The strengths of the present study include using a large item pool and a large sample with a large proportion of women in order to examine ASF as a predictor of sexual aggression beyond important control variables. Its weaknesses include the reliance on cross-sectional data, that preclude causal inferences, and not continuously distinguishing between consensual and non-consensual acts. <br /> Conclusion: ASF are a frequent phenomenon even in in the general population and among women and show strong associations with sexual aggression. Thus, they require more attention by research on sexual aggression and its prevention.
The life cycle of higher plants is based on recurring phases of growth and development based on repetitive sequences of cell division, cell expansion and cell differentiation. This dissertation deals with two projects, each of them investigating two different topics that are related to cell expansion. The first project is examining an Arabidopsis thaliana mutant exhibiting overall cell enlargement and the second project is analysing two naturally occurring floral morphs of Amsinckia spectabilis (Boraginaceae) differing (amongst others) in style length and anther heights due to differences in longitudinal cell elongation. The EMS-mutant eop1 was shown to exhibit a petal size increase of 26% caused by cell enlargement. Further phenotypes were detected, such as cotyledon size increase (based on larger cells) as well as increased carpel, sepal, leaf and pollen sizes. Plant height was shown to be increased and more highly branched trichomes explained the hairy eop1 phenotype. Fine mapping revealed the causal SNP to be a C to T transition at the last nucleotide of intron 7 of the INCURVATA11 (ICU11) gene, a 2-oxoglutarate /Fe(II)-dependant dioxygenase, and thus causing missplicing of the mRNA. Two T-DNA insertion lines (icu11-2 & icu11-4) confirmed ICU11 as causal gene by exhibiting increased petal size. A comparison of three icu11 alleles, which possessed different mutation-related changes, either overexpressing ICU11 or modified mRNAs, was the base for investigating the molecular mechanism that underlies the observed phenotype. Different approaches revealed contradictory results regarding ICU11 protein functionality in the icu11 mutants. A complementation assay proved the three mutants to be exchangeable and ICU11 overexpression in the wild-type led to an icu11-like phenotype, arguing for all three icu11 mutants to be GOF mutants. Contradicting this conclusion, the icu11-4 line could be rescued by a genomic ICU11 transgene. A model, based on the assumption that an overexpression of ICU11 is inhibiting the function of the protein, and thus causing the same effect as a LOF protein was proposed. Further, icu11-3 (eop1) mutants were shown to have an increased resistance towards paclobutrazol, a gibberellin (GA) inhibitor and an upregulation of AtGA20ox2, a main GA biosynthesis gene. Additionally, ICU11 subcellular localization was discovered to be cytoplasmic, supporting the assumption, that ICU11 affects GA biosynthesis and overall GA level, possibly explaining the observed (GA-overdose) phenotype.
The second project aimed to identify the genetic base of the S-locus in Amsinckia spectabilis, as the Amsinckia genus represents untypical characteristics for a heterostylous species, such as no obvious self-incompatibility (SI) and the repeated transition towards homostylous and fully selfing variants. The work was based on three Amsinckia spectabilis forms: a heterostylous form, consisting of two floral morphs with reciprocal positioning of sexual organs (S-morph: high anthers and a short style and L-morph: low anthers and a long style), and two homostylous forms, one large-flowered and partially selfing and the other small-flowered and fully selfing. The maintenance of the two floral morphs is genetically based on the S-locus region, containing genes that encode for the morph-specific traits, which are marked by a tight linkage due to suppressed recombination. Natural populations are found to possess a 1:1 S:L morph ratio, that can be explained by predominant disassortative mating of the two morphs, causing the occurrence of the dominant S-allele only in the heterozygous state (heterozygous (Ss) for the S-morph and homozygous recessive (ss) for the L-morph). Investigation of morph-specific phenotypes detected 56% elongated L-morph styles and 58% higher positioned S-morph anthers. Approximately 50% of the observed size differences were explained by an increase in cell elongation. Moreover, additional phenotypes were found, such as 21% enlarged S-morph pollen and no obvious SI, confirmed by hand pollinated seed counts, in vivo pollen tube growth and the development of homozygous dominant SS individuals via selfing. The Amsinckia spec. S-locus was assumed to at least consist of the G- (style length), the A- (anther height) and the P- (pollen size) locus. Comparative Transcriptomics of the two morphs revealed 22 differentially expressed markers that were found to be located within two contigs of a SS individual PacBio genome assembly, allowing the localization of the S-locus to be delimited to a region of approximately 23 Mb. Contradictory to revealed S-loci within the plant kingdom, no strong argument for a present hemizygous region was found to be causal for the suppressed recombination of the S-locus, so that an inversion was assumed to be the causal mechanism.
Recent research provides evidence that aggressive sexual fantasies predict aggressive sexual behavior in the general population. However, sexual fantasies including fantasies about the infliction of pain and humiliation, should be frequent and often consensually acted upon among individuals with sadomasochistic likings. The question arises whether sexual fantasies with aggressive content still predict presumably non-consensual aggressive sexual behavior in individuals with sadomasochistic likings, given that BDSM encounters are generally considered consensual. To investigate this question, we conducted a questionnaire survey of sexual fantasies, as sessing the frequency of seventy sexual fantasies involving non-aggressive, masochistic, and aggressive acts. Our sample (N = 182) contained 99 respondents who self-identified as sadist, masochist, or switcher; 44 reported no such identification. For respondents reporting BDSM identification, we replicated a factor structure for sexual fantasies similar to that previously found in the general population, including three factors reflecting fantasies about increasingly severe aggressive sexual acts. Fantasies about injuring a partner and/or using weapons and fantasies about sexual coercion predicted presumably non-consensual sexual behavior independently of other risk factors for aggressive sexual behavior and irrespective of BDSM identification. Hence, severely aggressive sexual fantasies may predispose to presumably non-consensual sexual behavior in both individuals with and without BDSM identification.