Evidence-Based Veterinary Medicine (EBVM) is a relatively new field in veterinary curricula and veterinary practice. The aim of EBVM is to base clinical decisions regarding diagnostic procedures and treatments on recent, valid, clinically relevant research data. Veterinary practitioners and clinicians should use optimal diagnostics, interventions and medications to examine and to treat their patients. Therefore, they should assess the topicality of their procedures and therapies to treat their patients as best as possible. This means clinicians need skills in observation, manual dexterity, and also other skills such as communication and empathy for patients and owners. Specifically, the EBVM concepts should be incorporated into preclinical and clinical courses. For the realization of an evidence- based patient care, it is important to know core concepts of EBVM and to be skilled in five steps: formulation of a clinical question, searching for literature, assessing the validity and applicability, the implementation into practice and finally an assessment of whether the new findings have improved clinical practice. Rather than merely transferring information, veterinary education should stimulate and motivate students and let them think critically. Frontal teaching, however, is still applied frequently in veterinary education which only rarely stimulates student interaction, besides it does not support independent thinking and critical questioning. In addition to the concept of EBVM, the critical thinking, and also the rapid development of new communication technologies has influenced veterinary education already. One helpful tool to facilitate the access to research results and thereby the implementation of Evidence-Based Medicine (EBM) is a Critically Appraised Topic (CAT). A CAT is a standardized summary of research evidence evolved around a clinical question, generated from a specific patient situation or problem. The overall objective of the conducted studies was to survey possibilities to include EBVM concepts in veterinary education. For this purpose three studies were conducted: 1\. In the first study the research question was, if fourth-year students consider in-course discussion useful and if sufficient possibilities for discussion are provided and supported by their lecturers. The majority agreed or strongly agreed that clinical topics should be discussed during class time. Frequently stated reasons were improved learning and the opportunity to look at topics from different perspectives. In conclusion, a considerable absence of and request for discussion within veterinary education was found. In light of these findings, we emphasize the need for new teaching strategies that promote independent thinking and critical questioning. That suggested the implementation of more discussion opportunities in well considered and moderated settings in veterinary teaching. 2\. The research question of the second study was to determine adoption and use of mobile devices and online services of veterinary students. According to their answers the majority used a smartphone as mobile device. The data suggested, that most students are familiar with mobile devices and the use of social media, so that new learning strategies could be developed and applied that encompass mobile online learning. These strategies could help to better address different learning types, provide sufficient interactivity and feedback. However, despite promising results reporting a positive educational effect, these perceptions need to be validated in further research. 3\. The objective of the third study was the development, the use and an evaluation of a German language database for Critically Appraised Topics (CATs). Experts of the European Board of Veterinary Specialization were asked to appraise CATs written by students. A total of 153 veterinary medicine students in their fifth year developed 21 CATs. The majority of the students stated that writing CATs is a good exercise and that it is important to train the assessment of scientific information. Nine out of 13 CATs were graded as ´good`. In conclusion veterinary medicine should in general be more responsive to the integration of recent literature and to a critical approach of information. Specifically, the development of a CAT by students is a good approach to teach the concepts of EBVM. In consideration of new technologies, the CAT-database can be used by German veterinary students and in the future by practitioners.Weniger anzeigen
Most people are not aware of the potential health risks associated with the ingredients of daily used polymeric consumer products. The application range is as diverse as the composition of the materials. Polymeric material is exemplarily used in tool handles, food contact materials and toys. It is thus even more important that the final product is harmless to health and ensures safe usage over the entire product life cycle. Analyzing the composition, intentionally added substances need to be distinguished from non-intentionally added substances. Unlike substances that were added for a defined purpose (e.g. plasticizers, antioxidants or processing aids), non-intentionally added substances are present as a result of material aging or inappropriate manufacturing processes (e.g. contaminants, decomposition or reaction products). In this thesis, the focus was on polymeric consumer products that are designated for skin contact. Besides the oral and inhalative route, the dermal path of exposure may pose a major route for xenobiotics to enter the organism. This is of special concern in case of toxicological relevant xenobiotics like polycyclic aromatic hydrocarbons (PAHs), aminobenzene- or cresol-derivatives. There is an EU-wide restriction on 8 PAHs that are classified as presumed to have carcinogenic potential to humans in toys and consumer products effective since 2015 (REACH EG No. 1907/2006, EU No. 1272/2013). Articles shall not be placed on the market if any of their rubber or plastic components that come into direct as well as prolonged or short-term repetitive contact with the human skin contain more than 0.5 mg/kg or 1 mg/kg respectively. The limits set refer to the PAHs content in the material and do not mirror the actual dermal exposure of consumers. Therefore, it is crucial to study the real dermal PAH load in order to generate data for a reliable assessment of potential health risks. In this thesis, dermal exposure to leachables of rubber and elastomers was investigated consequently using excised human skin in the Franz diffusion cell (FDC)-assay. Basing on this reference data, an alternative testing method was developed for dermal exposure assessment of PAHs. It uses a simulant suitable for the lipophilic PAHs and it realistically mirrors the combined permeation and migration of PAHs. Exposure data basing on this method was provided for the European Commission in order to review the limit values of PAHs in consumer products and toys. The skin permeation was visualized at the example of the procarcinogen N-phenyl-2-naphthylamine. Human skin was exposed ex vivo to a polyolefin entailing this antioxidant and a depth profile generated applying ATR-FTIR-microscopy. It was shown by this very graphic evaluation, that numerous polymer additives with in part toxicological relevance might migrate, overcome the skin barrier and ultimately lead to a potential health risk. A detailed characterization of the polymeric material was conducted using broad analytics. The development of multi-analyte-methods allowed quantification of 21 additives, 5 degradation products and 28 PAHs. The polymers were identified applying pyrolysis coupled online to gas chromatography and mass-spectrometric detection. Furthermore, additives were tested in different aging protocols to identify potential degradation products of toxicological relevance. It was shown, that cresol-derivatives are formed as a consequence of degradation of phenolic antioxidants and phthalates are formed by degradation of a phthalate substitute plasticizer. The results of this work can be useful to improve risk identification and to prioritize leachables of elastomers and rubber for risk assessment.Weniger anzeigen
Photosynthesis is one of the most fundamental processes on Earth fuelling life by providing food and energy. Moreover, terrestrial vegetation is a key element in the climate system as it importantly affects exchange processes of carbon, water and energy between the land surface and the atmosphere. In times of a changing climate there is urgent need for detailed knowledge on the factors driving plant activity and for reliable observational systems of the terrestrial vegetation. Satellite remote sensing is the only means to obtain measurements with global coverage, including remote and inaccessible regions, in a spatially and temporally continuous manner. This thesis presents an assess- ment of our current observational capabilities of vegetation dynamics from space. Three complementary approaches of spaceborne ecosystem monitoring are inter-compared: 1) Spectral measurements of the land surface reflectance in the optical range give an indica- tion of the amount of green biomass (as an integrative signal of leaf quantity and quality) and hence of the potential to perform photosynthesis. 2) In the red and far-red spectral regions, satellite instruments register a very small additive signal to the reflected radiance which originates from photosynthetically active chlorophyll pigments, termed sun-induced chlorophyll fluorescence (SIF). 3) Carbon fluxes measured in-situ are upscaled to a global data set of model gross photosynthetic carbon uptake (known as GPP - gross primary production) using empirical relationships with remotely sensed land surface and environ- mental variables. Three case studies focus i) on the spring phenology in boreal forests, ii) on the peak growing season in circumpolar treeless regions, and iii) on phenological changes in ecosystems with varying abundances of trees globally in times of fluctuations in soil moisture availability. The results of all three case studies highlight the intrinsic differences between greenness on the one hand and photosynthetic activity on the other hand. Specifically – for the first time on synoptic scales – a decoupling of photosynthesis (as indicated by SIF and model GPP) and greenness (approximated by various indices derived from spectral reflectance measurements) could be observed in evergreen needleleaf forests during spring recovery. Similarly, a temporal mismatch occurs in northern hemi- sphere forests during the growing season. There, changes in incoming light co-vary with soil moisture and immediately affect photosynthetic performance but barely greenness. Moreover, it has emerged that the timing of peak photosynthesis and peak greenness are asynchronous in tundra areas, which is indicative of differing dynamics. Conversely, there is high consistency between the three approaches regarding the length of growing season in deciduous forests and moisture-related phenological shifts in non-forested ecosystems. The work in this thesis demonstrates that SIF represents an asset for the monitoring of the dynamics of photosynthesis and carbon uptake compared to greenness-based ap- proaches. There are further indications of SIF to track changes in photosynthetic yields. However, despite these promising results for the accurate tracking of photosynthesis from space, further research is required to provide higher resolution data sets with clearer sig- nals. Further, ground-based validation efforts are necessary to improve our mechanistic understanding of physiological and radiative transfer processes controlling the SIF signal.Weniger anzeigen
When investigating the evolution of language, scientists often approach one prominent question: What makes humans human? While researchers might share a common question that motivates them to investigate the origin of language, they do not share a common definition of that original term. The current dissertation hypothesises that definitions of language are ever-changing, temporary constructions which are implicitly informed by historical and social values. By utilising a mixed-methods approach, which combines socio-historical research with quantitative strategies, three examples are investigated: (i) Language defined as speech (oral norm); (ii) Language defined as highest evolutionary achievement (Scala Naturae); (iii) Language defined from its external structure (Behaviourism). The dissertation reveals and illustrates that each of the historical constructions has its problems. Regarding (i), a historical argument from analogy to the deaf discourse reveals prejudices towards nonverbal forms of communication. Addressing (ii), a quantitative text analysis on 915 articles from a time span of 10 years testifies the use of value-laden adjectives in some publications. Analysing (iii), a citation network on 653 articles, published over the time of 69 years, illustrates how the term intention enters a discourse that originates from a behaviouristic era and turned into a cognitive one. The quantitative evidence revealed by the dissertation demonstrates: Science is not, never was and likely never will be free from social and historical influences. That is not a problem. It is a problem, however, to neglect or ignore those influences. The current meta-analysis points to them in order to enable the reader to develop a critical standpoint in relation to the current and past language origin discourse. Hence, providing evidence by systematic investigation of these values is an active contribution to scientific self-correction.Weniger anzeigen
Small rodents and their nests are fascinating and existential biotopes for numerous arthropod, helminth and protozoan animals. On the other side, some of the parasite species can cause disease in humans and companion animals and wild mice and voles are reservoir hosts for many tick-borne pathogens. Despite that, the biodiversity and quantitative occurrence of many wild rodent parasites and their zoonotic potential is largely unknown. Six rodent species from the genera Apodemus, Myodes and Microtus are presumably the most abundant non-commensal rodent species in Europe and also among the most important hosts for immature life stages of ticks in urban areas like Berlin. In the first instance, the present thesis therefore reviewed for the first time all the 460 invertebrate and 69 protozoan species which were reported from these six rodent species in Europe and gave a brief overview about the taxonomy, major morphological characteristics, life cycles and zoonotic potential of the macroparasites and intestinal Coccidia associated with these rodents. In a longitudinal field study, 257 rodents of these six species were trapped at four study sites in Berlin and examined for intestinal Coccidia, macroparasites and other invertebrates. The ectoparasites, as well as phoretic and non-parasitic arthropods detected in the fur and on the skin of the rodents were covered in manuscript 1, while helminths and intestinal Coccidia were addressed in manuscript 2. A high taxon richness of at least 84 species, comprising 63 arthropod, 20 helminth and one higher coccidian taxon was observed on/in the rodents in Berlin and no rodent individual was free of parasite infections. The tick Ixodes ricinus was the most frequent species with 56% prevalence and a mean intensity of 9.4 ticks per rodent host. Eight mite and one nematode species represent new records for the fauna of Germany. Rodent species, trapping location and season were clearly associated with the quantitative occurrence of most parasite groups. Mice were more often parasitised by digenean flukes, hymenlepidid tapeworms, the nematode Heterakis spumosa, lice and listrophorid mites but less often by anoplocephalid tapeworms, trombiculid and myocoptid mites than voles. In non-metric multidimensional scaling, host species even appeared to be more important than trapping location, since rodent individuals could mostly be allocated to one of three host taxon groups, only according to the parasite taxa they harboured. However, the different degrees of urbanisation between the trapping locations affected not only the presence and abundance of the rodent species, but also the species richness of rodent parasites. Compared to rural areas, mice and voles in Berlin carried less arthropod species with low host dependence and host specifity, such as fleas, trombiculid and non-parasitic gamasid mites. Furthermore, ecto- and endoparasites with lower host adaptation and high dependence on intermediate hosts or other external factors were decreasingly diverse, prevalent and/or numerous with increasing degree of urbanisation from periurban to urban sites. Endoparasites without host change (monoxenous) and stationary ectoparasites, in contrast, were more prevalent and/or numerous at urban sites. Apart from ticks, the parasites detected on the six peridomestic rodent species in Berlin only pose a minor zoonotic risk of infection for people, since species causing severe diseases, such as Echinococcus multilocularis were absent. In contrast, the role of these hosts in the urban life cycle of ticks is important and they most certainly participate in the maintenance of well-known and emerging tick-borne pathogens in Berlin. Hence, regression analyses were performed to assess the influence of co-infections on tick abundance on the rodent host. Considering several confounding factors, the abundance of I. ricinus larvae was negatively associated with the abundance of nematodes from the superfamily Heligmosomoidea and Syphacia sp., as well as of gamasid mite parasites from the family Laelapidae, while that of hymenolepidid tapeworms was positively associated. To verify a relationship of cause and effect, laboratory co-infection experiments were conducted and published in manuscript 3. Mice simultaneously infected with Heligmosomoides polygyrus nematodes as well as with larval or nymphal I. ricinus ticks exhibited substantially higher systemic type 2 T helper cell (Th2) responses, based on interleukin 13 and GATA 3 expression compared to single-infected mice. However, the development of partial immunity and the Th2 reactivity towards ticks were unaffected by the nematode infection during repeated larval tick infestations. Co-infections with H. polygyrus were also unable to affect the susceptibility for tick-transmitted Borrelia afzelii Lyme disease spirochetes and their replication, dissemination and induction of signs of pathology in the rodent host. The negative association between heligmosomoid nematodes and ticks in wild rodents could not be confirmed in laboratory mice. However, the observed negative effect of laelapid mites on tick abundance, which may be caused by predation, should be further investigated. These mites have the potential to affect feeding success of ticks and therefore the transmission of many tick-borne pathogens. The present field study constitutes a current basis for studies on parasite diversity, arthropod vector competence and natural co-infections.Weniger anzeigen
Imaging of the rupture process of an earthquake produces valuable insights on the kinematics of earthquakes. In earthquake seismology rupture propagation imaging has been applied impressively to many megathrust events to visualize the rupture process and path. This can help to comprehend the cascade of processes within an ongoing earthquake and consequently it may help to improve hazard mitigation measures. As the coverage of seismic stations and the quality of the instruments has been increasing rapidly in the last years, there is a growing potential to apply similar imaging approaches to medium-sized and small earthquakes, too. In this thesis, I implement and apply three different rupture imaging techniques to infer rupture properties from events at local and at microseismic scales covering magnitudes of 1 ≤ M ≤ 8: the back projection imaging, the empirical Green’s function analysis, and the P wave polarization stacking. I examine two different data sets: the fluid-induced microseismicity from the enhanced geothermal system in Basel, 2006, and the natural occurring seismicity in the vicinity of the rupture area of the 2014 MW 8.1 Iquique earthquake in northern Chile. In a first study, I carefully adjust, numerically test, and apply the back projection technique in the microseismic reservoir at the Basel EGS. The results demonstrate for the first time that back projection imaging is capable of illuminating the rupture process at scales where events have rupture lengths of only a few hundred meters. To complement this study, I perform a second study based on empirical Green’s function analysis in combination with directivity measurements for the smaller magnitude events at this site to estimate corresponding rupture orientations and directions. Based on the combination of the two imaging approaches, I find valuable results for a larger amount of events which cover a broader spectrum of magnitudes compared to a single method approach. The combined results indicate that the rupture behavior at the Basel reservoir appears to be magnitude-dependent and it is strongly influenced by the induced pressure-field from the injection. At the northern Chilean subduction zone, numerous foreshocks and aftershocks of the 2014 MW 8.1 Iquique event were recorded by the Integrated Plate boundary Observatory Chile, which I use to perform P wave polarization stacking to find rupture orientations of 5 ≤ M ≤ 8 events. Although applied to huge teleseismic events before, this is the first successful application of this technique at local scale. My estimated directions are in good agreement with independent back projection studies for the Iquique event itself and its largest foreshock and aftershock. In a second study, I apply empirical Green’s function analysis at the same site for events with 2.6 ≤ M ≤ 5.3. Again, the combination of the results of the two methods yields important findings: the distribution of orientations of rupture directions shows a preferred direction towards east, which is the down-dip direction. It is less sharp for the larger magnitude events and it led to the hypothesis that a bimaterial effect at the plate interface could be responsible for the observed preferred rupture direction. The effect appears to be stronger pronounced for smaller events which are not capable to overcome the barriers of the asperity of their nucleation. In this thesis, three rupture propagation imaging approaches were adjusted in a way that it became possible to analyze events of significantly smaller scale than previously feasi- ble. This thesis shows that the integration of multiple imaging approaches can produce enhanced results for the same data set and how to achieve them. For the further study of the physics of earthquake rupture processes, we need more comprehensive data on the rupture behavior.Weniger anzeigen
„Der Lebenszyklus eines dPon in den konföderierten Stammesgesellschaften von Nangchen vor 1959“ ist eine ethnologische und tibetologische Monographie über den Lebenszyklus der dPon genannten Führungspersonen der vereinten Nangchen-Stämme mit dem Ziel der Bewahrung kultureller Kenntnisse. Das einstige Königreich Nangchen im Nordosten des tibetischen Plateaus beruhte auf einer Stammeskonföderation. Gegenwärtig wird das Gebiet „Yushu Tibetische Autonome Präfektur“ genannt und liegt im Süden der chinesischen Provinz Qinghai. Nangchen war eines der Länder, die vor 1950 zwischen Tibet und China lagen. Die Ortsbezeichnung „Nangchen“ tritt in zwei Bedeutungen auf: für das Territorium der vereinten Nangchen-Stämme mit 188.794 km2, auch als „Königreich Nangchen“ benannt, sowie als das darin gelegene Land Nangchen mit einer Fläche von 12.741 km2. Der Untersuchungszeitraum erstreckt sich von ca. 1918 bis 1959. Die Darstellung des Lebenszyklus beginnt mit der pränatalen Phase und geht über die Lebenszeit der dPon hinaus bis zur Amtsübernahme der Nachfolger. In der Position des dPon gab es die Ränge Behu und Becang. Verständlich wird das Handeln der dPon erst unter Einbeziehung ihrer Welt- und Wertvorstellungen, der Kategorien des Denkens und Empfindens, religiöser Einflüsse und der Lebensumstände in der adligen Oberschicht im Vergleich zur übrigen Bevölkerung. Die Eigenschaften eines vorbildlichen dPon repräsentierte Khra rGan aus dem Gesar-Epos. Nachfolger seines Stammes sMug-po gDong (Schreibvariante: sMug-po lDong) lebten in Nangchen. Die Darstellung zeigt Anschauungen der Bevölkerung aus verschiedenen gesellschaftlichen Schichten und Gruppen unter Einbeziehung authentischer Fallschilderungen und Sprichwörter und eingebettet in die historische Entwicklung vor und nach dem Einmarsch der Volksbefreiungsarmee (PLA) der VR China (PRC) und bezugnehmend auf Entwicklungen im Exil. Das politische Handeln war durch die geopolitische Lage zwischen weitaus mächtigeren Reichen bestimmt in dem Bestreben, die Souveränität Nangchens zu bewahren. Beschrieben sind unter anderem die Rekonstruktion der politischen und administrativen Organisation, das Amt der dPon: Aufgabenbereiche und Arbeitsweisen, Rechtsformen, juristische Strategien, Konflikte und Lösungsmethoden, weitere berufliche Tätigkeiten, Mitarbeiter des dPon, die Gesellschaft, Kindheit und Jugend, Verwandtschaftsterminologie, der Einfluss des Klerus, die Situation von Frauen, gesellschaftliche Randgruppen, Kategorien von Freundschaft und Formen der Ehe. Themenbezogen wurden soziale und ökonomische Strukturen rekonstruiert und die materielle Kulturausstattung. Das gehäufte Auftreten vieler scheinbar metaphysischer Phänomene in der Literatur, in Erzählungen und Berichten wird erklärt, darunter die „Wiederaufgestandenen Toten“ (tibetisch: Ro-langs) und der Yetis (tibetisch: ‘Dre-mong). Viele kulturelle Phänomene werden erstmals aus der emischen Perspektive beschrieben, so dass die Kultur aus der Innensicht verständlich wird.Weniger anzeigen
Die vorliegende Studie geht von einem in mehrfacher Hinsicht „außergewöhnlich normalen“ Kindsmordprozess aus, der in den Jahren 1760-66 im gemeinschaftlich regierten Assenheim stattfand. Die soziale und kulturelle Komponente bei den institutionellen und diskursiven Vorgängen rund um die gerichtliche Untersuchung wird durch eine umfassende Kontextualisierung des Falles um Maria Magdalena Kaus herausgearbeitet. Durch ein akteurszentriertes Vorgehen, welches auf den Vorgaben der überlieferten Quellen basiert, werden gleichzeitige, sich überlagernde Netzwerke, Klientel- und Verwandtschaftsverhältnisse innerhalb der Kleinstadt sichtbar und somit wichtige Rückschlüsse auf Handlungsoptionen der historischen Akteurinnen und Akteure geliefert. Die Herrschafts- und Gerichtspraxis innerhalb Assenheims wurde durch das Kondominat, d. h. die gemeinsame Landes- und Kirchenherrschaft, der Grafen von Solms-Rödelheim und Assenheim, Ysenburg-Büdingen-Wächtersbach und Hanau bestimmt. Während sich der Besitzanteil an der Stadt im Falle der beiden ersteren und kleineren Herrschaften auf 5/12 belief, verfügte das größere Hanau lediglich über 2/12. Doch machtpolitische Gegebenheiten außerhalb des Kondominiums spielten bei der alltäglichen herrschaftlichen Praxis in Assenheim eine untergeordnete Rolle. Auch die Konfessionsunterschiede zwischen der evangelisch-lutherischen Mehrheit aus Solms-Rödelheim-Assenheim und Hanau und dem reformierten Ysenburg-Büdingen-Wächtersbach bedingten abgesehen von kirchlichen Angelegenheiten keine vorgegebene Positionierung gegenüber den beiden verbleibenden Kondomini. Das Verhältnis der drei Herrschaften untereinander kann folglich zumindest für die Zeit von 1740 bis 1790 nicht verallgemeinernd beschrieben werden: es handelte sich vielmehr um eine komplexe Beziehung, die sich je nach Angelegenheit und jeweiligen Interessen figurierte. Zugleich und vermutlich auch aufgrund dieses Handelns, das in erster Line von machtpolitischen Eigeninteressen vorgegeben wurde, kann jedoch im Falle aller drei Herrschaften von einer latenten Atmosphäre des Misstrauens gegenüber den Mitherrschaften gesprochen werden. Dies traf insbesondere auf Hanau zu, welches vor allem aufgrund seiner geringeren Besitzanteile fürchtete, von den beiden übrigen Grafschaften übervorteilt zu werden. Dass die kondominatorische Herrschaft gegebenenfalls auch zusätzliche Handlungsoptionen für die AssenheimerInnen in Form einer gezielten Instrumentalisierung des Herrschaftsverhältnisses eröffnete, zeigt sich beispielhaft an einer Supplikation des Ehepaares Kaus, das die Kondomini durch den Verweis auf einen Beschluss Hanaus unter Druck zu setzen versuchte. Da die gemeinsame Landesherrschaft ein einstimmiges Urteil voraussetzte, konnte eine schon bestehende Entscheidung möglicherweise auch das Urteil der beiden anderen Parteien beeinflussen. Der Abschluss des Prozesses gegen Maria Magdalena Kaus zeigt hingegen, dass das Einstimmigkeitsprinzip auch zu einem für die/den Supplizierende/n ungünstigen Entscheid führen konnte. Insgesamt erscheint die Bestrafung der jungen Kausin „traditionell“. Ansätze einer von den unteren Gerichtsinstanzen ausgehenden Humanisierung, wie sie Helfried Valentinitsch bereits in der zweiten Hälfte des 17. Jahrhunderts in den innerösterreichischen Ländern bei einer Betrachtung von Kindsmorden ausmachen konnte, lassen sich bei einer genauen Analyse des Prozesses gegen Maria Magdalena Kaus nicht erkennen. Während sich das Strafmaß im Fall Kaus aus Ermangelung eigener neuerer Gesetzestexte weitgehend an der Peinlichen Halsgerichtsordnung Kaiser Karls V. aus dem Jahr 1532 und deren Kommentatoren bemaß, wurde den sozialen Umständen oder möglichen Motiven der Angeklagten kein Interesse im Verlauf der gerichtlichen Untersuchung entgegengebracht. Von Beginn an wurde Maria Magdalena Kaus von obrigkeitlicher, medizinischer und juristischer Seite mit Ausnahme ihres Defensors, der sie als „unschuldiges einfältiges Mädgen“ zeichnete gemäß der Figur der „boshaften Kindsmörderin“ konstruiert. Dabei griffen die männlichen Richter und Gutachter auf zeitgenössische Geschlechterstereotype zurück, welche so reproduziert und gefestigt wurden. Vor dem Hintergrund der bürgerlichen Moral, die außereheliche Sexualität unter Strafe stellte, wurde Maria Magdalena Kaus im Verlauf der gerichtlichen Untersuchung stigmatisiert und degradiert. Zugleich zeigt die Betrachtung des Prozesses und seines Kontextes die allgegenwärtige Diskrepanz von kodifizierter Norm und Praxis im frühneuzeitlichen Assenheim, u. a. im Bereich des außer- bzw. vorehelichen sexuellen Verkehrs. Denn obwohl allein die Ehe im 18. Jahrhundert den sexuellen Verkehr legitimierte und eine Schwangerschaft vor diesem Hintergrund ein untrügliches Zeichen eines vorangegangenen Unzuchtdelikts darstellte, machte ein beträchtlicher Teil der AssenheimerInnen unabhängig von seinem sozialen Status außereheliche sexuelle Erfahrungen. Innerhalb des Dreiecksverhältnisses zwischen Landesherren, Verwaltungen und Bevölkerung verfügten alle Akteurinnen und Akteure über Möglichkeiten, die lokale Herrschaftspraxis zu beeinflussen. Durch die gemeinschaftliche Landes- und Kirchenherrschaft ergaben sich dabei auf allen drei Ebenen eingeschränkte, aber auch erweiterte Handlungsfreiräume. Insgesamt wurden diese Handlungsspielräume sowohl auf Seiten der Grafen und Regierungen, der lokalen Funktionsträger und der Bevölkerung nicht von Koalitionen oder Rivalitäten, sondern von (machtpolitischen) Einzelinteressen bestimmt und stellten sich dementsprechend variabel dar.Weniger anzeigen
Layered intrusions are stratified igneous bodies, which are of outstanding scientific and economic interest. They form due to accumulation of crystals on a solidifying crystal mush and represent ‘natural laboratories’ providing direct insights into fundamental petrological concepts like crystal accumulation or magma differentiation. In addition to their petrological significance, they host some of the world’s most important reserves of base and precious metals, including the platinum-group elements. Among the most prominent, but also most enigmatic, examples of magmatic layers in layered intrusions are Cr-spinel seams or chromitites. Despite the wealth of studies and the long history of research, spanning several decades, the petrogenesis of Cr-spinel layers, i.e. the processes of accumulation and possible subsequent modification, is still incompletely understood and riddles the scientific community till today. This thesis aims to shed some light on this active debate to advance our knowledge and understanding on the petrogenesis of these layers. Therefore, Cr-spinel seams in two case studies, the Bushveld Complex, South Africa and the Rum Layered Intrusion, NW Scotland, were investigated by detailed field observations and micro-analytical examination of the textural and mineral chemical character of the accumulated crystals. These observations were used to elucidate the processes of initial Cr-spinel accumulation and post-cumulus processes, which subsequently modified the primary chemistry and texture.
Post-cumulus processes that modify the original composition or texture of crystals within the crystal mush are known for a long time. Several studies have emphasised the added uncertainty in the interpretation of potentially modified textures and compositions. Thus, this thesis aims to assess post-cumulus changes within the seams to understand the involved mechanism and deduce the original characteristics of cumulus Cr-spinel. Micro-textural analyses of Crspinel in the Bushveld Complex reveal two typical textural types, one characterised by small grains, commonly entrapped in oikocrysts and the other by massive, coarse-grained Cr-spinel. While the former kept its original texture due to the protecting oikocrysts, the latter was modified by adcumulus growth and subsequent textural equilibration. In addition, geochemical observations of the oikocrysts reveal that the Cr-spinel layer was an open system, which was infiltrated by a trace element enriched interstitial melt re-equilibrating with the orthopyroxene oikocrysts. Contrary to the layers of the Bushveld Complex, the investigated seams of the Rum Layered Intrusion retained a more primary texture, indicating less adcumulus growth and textural equilibration. Here it is demonstrated that careful examination of Cr-spinel offers a thorough understanding of the processes involved in post-cumulus modifications, which therefore can be used to identify and deduce the primary characteristics of accumulated crystals.
A huge variety of contrasting petrological models are currently discussed to account for almost monomineralic Cr-spinel seams among them are changes in parameter (e.g. change pressure, oxygen fugacity, composition due to mixing, etc.) or mechanical enrichment processes. In this thesis, micro-analytical measurements of Cr-spinel seams were utilised to trace vertical variations across Cr-spinel seams of the Bushveld Complex and lateral variations in the Rum Layered Intrusion. The compiled data suggest that Cr-spinel accumulation was controlled in both case studies by physico-chemical processes and not by mechanical ones, i.e. neither large-scale crystal settling nor cumulate mobilisation due to Cr-spinel-rich slurries can account for the reported mineral chemistry and texture. Moreover, lateral variations in seam structure and Cr-spinel composition were observed along strike in the Rum Layered Intrusions and to a certain extent in the Bushveld Complex. These variations suggest that the accumulation process was closely linked to repeated influxes of new, primitive magma. These repeated replenishing events within single layers were followed by assimilation of the underlying crystal mush and subsequent fractionation, resulting in the observed lateral and vertical variations.Weniger anzeigen
„Media Capture“ findet statt, wenn Eliten (in-)direkte Strategien aufwenden, um vorteilhafte Informationen zu verbreiten oder unvorteilhafte Informationen zu unterdrücken (Besley & Prat, 2006; Corneo, 2006). Die Bedeutung von „Media Capture“ zu kritischen Zeitpunkten, wie beispielsweise Wahlperioden, hatte bereits entscheidende Auswirkungen in der Vergangenheit. Im Fall von „Media Capture“ ist die Wahlentscheidung von Individuen durch die Informationen die diese beziehen, beeinflusst (Besley & Prat, 2006a, p. 721; Enikolopov et al., 2011). Dies ist insbesondere in Zentralamerika relevant, wo der Großteil der ohnehin eingeschränkten Informationen der Menschen im Hinblick auf politische Parteien, Ideologien und Politik im Allgemeinen, aus den Medien stammen (Besley & Prat, 2006a, p. 721; Enikolopov et al., 2011). Bestehende Fachliteratur zu Eliten zeigt die essentielle Bedeutung politischer Wahlen in den Strategien der Wirtschaftselite, insbesondere wenn diese sehr abhängig davon ist, das Land zu kontrollieren (Acemoglu & Robinson, 2006; Bull, 2014; Durand, 2016). Daher ist „Media Capture“ besonders wesentlich für Eliten, wenn politische Wahlen anstehen, da zu dieser Zeit ihr Einfluss unter Umständen bedroht wird. Diese Forschungsarbeit analysiert und erforscht wie, und zu welchem Ausmaß, Eliten „Media Capture“ betreiben, wenn sie sich bedroht fühlen, am Beispiel der Präsidentschaftswahlen 2014 in Costa Rica und El Salvador. Diese Studie bietet eine frische Perspektive auf Eliten und deren Strategien sowie auf Anti-Eliten und Mediennetzwerke. In diesem Forschungsprojekt zeige und argumentiere ich, dass Eliten bezüglich „Media Capture“ verschiedene Strategien in ihrem Repertoire haben und dass ihre Erfolgschancen sich verändern und drastisch erhöhen, sobald sie vereint vorgehen, und wenn es eine Art Netzwerk gibt, welches Gegenstimmen einschränkt. Dies wiederum erweitert drastisch ihre Kapazitäten, die Gesellschaft zu beeinflussen. Wie der Fall von Costa Rica zeigt, findet koordinierte „Media Capture“ statt, wenn Eliten sich vereinigen und wenn die Art von Netzwerk zwischen Eliten und Medien elitär ist. Auf der anderen Seite hat die Fragmentierung der Elite in El Salvador „Media Capture“ in eine Arena der Auseinandersetzung zwischen Eliten und Anti-Eliten verwandelt. Diese Forschungsarbeit wendet eine Vorgehensweise gemischter Methoden an, mit dem primären Ziel, auf diesen gegenseitig aufzubauen und zu komplementieren. Methoden der Datenerhebung beinhalten direkte Befragungen von Eliten sowie Aufzeichnungen. Diese Studie bietet tiefe Einblicke im Hinblick auf Faktoren, welche „Media Capture“ vereinfachen und auf die Art von Strategien und Maßnahmen, die Eliten ergreifen, um vorhandene Informationen zu verändern oder zu unterdrücken.Weniger anzeigen
The kingdom of fungi comprises an enormous range of live styles and genetic variability. Different genomics approaches offer possibilities to investigate species diversity and ecological function of fungi. In this thesis I present improvements of metabarcoding methods for aquatic fungi and the application of whole genome sequencing and transcriptome sequencing to an exclusively aquatic fungus. Beside the standard metabarcoding marker for fungi, the ITS (internal transcribed spacer) region, the eukaryotic rRNA operon contains two other markers, the SSU (small subunit) and LSU (large subunit), that are also often used for metabarcoding. When choosing a metabarcode there is a tradeoff between high variability for fine grain species delineation and high conservation for good primer binding and high level classification of novel species, which are not represented in reference databases. In the work presented in chapter III, we investigated the possibility to use the information from the more conserved 5.8S sequence, that is part of many amplicons used for ITS2 sequencing. It is normally discarded, but we used it as a complementary marker to ITS2 and showed that it can improve classification of novel species with an incomplete reference database. In chapter IV this is taken one step further by using third generation sequencing to sequence the full ITS region together with the more conserved SSU and LSU in the same amplicon. This gives us the option to use different markers with different databases for classification in parallel and to circumvent the trade-off between high variability and high conservation. Fungi are ecologically very important decomposers of lignocellulose from plant biomass. The occurrence and expression of gene families for the degradation of lignin from lignocellulose has been extensively studied with whole genome and transcriptome sequencing in terrestrial, but not in aquatic fungi. In the work presented in chapter V, we used whole genome and transcriptome sequencing to investigate differential gene expression in the exclusively aquatic fungus Clavariopsis aquatica when grown on media with more and less lignin rich carbon sources and investigated the expression patterns of peroxidases, laccases and other protein families involved in plant biomass degradation. This observed up-regulation of laccases, peroxidases and genes from the cytochrome P450 super-family, as well as other gene families involved in cellulose and hemicellulose degradation, strongly suggests that C. aquatica is able to modify lignin to some extent; perhaps in order to facilitate the utilization of lignocellulose as a carbon and energy source.Weniger anzeigen
The rumen of cattle and sheep is a large fermentation chamber where symbiotic microbiota break down otherwise indigestible fibrous components of feed to short chain fatty acids (SCFA), which represent the most important energy source for ruminants. To obtain optimal conditions for ruminal fermentation, ruminal fluid needs to be buffered sufficiently to avoid acidic conditions, which involves buffering by bicarbonate (HCO3-) entering the rumen with saliva. Surprisingly, however, the buffering constants of the bicarbonate system have never been determined in ruminal fluid, compromising the ability to estimate the contribution of this system to ruminal buffering. Furthermore, ammonia can accumulate to toxic levels in the rumen due to fermentational deamination of protein and non-protein nitrogen. In part, this ammonia can be incorporated into high-grade microbial protein, but amounts exceeding microbial capacity must be absorbed from the rumen, hepatically detoxified and renally excreted, with detrimental consequences both for the protein efficiency of the ruminant and for the environment. Therefore, interest in identifying and characterizing the efflux pathway for ammonia from the rumen is considerable and enhanced by the fact that ruminal efflux of ammonia has long been known to involve absorption of the ionic form (NH4+) through a cation channel, thus contributing to elimination of protons and ruminal pH homeostasis. The present thesis aimed to answer two unsolved questions regarding to ruminal buffering: 1. What are the buffering constants for the bicarbonate buffering system in ruminal fluid? 2. What is the molecular identity of the transport protein that mediates the absorption of NH4+ from the rumen? The first part of the thesis focussed on the determination of the buffering constants of the bicarbonate system in ruminal fluid (Paper 1, Hille et al., 2016). In this open buffer system, ruminal protons are mainly buffered by HCO3- that enters the rumen with saliva or via secretion of the ruminal epithelium. To calculate the buffer capacity of ruminal fluid, the solubility of CO2 (α) and the equilibrium constant of CO2/HCO3- (pK) needed to be known, neither of which have previously been determined for ruminal fluid. Accordingly, ruminal fluid from cattle fed either hay or concentrate diets was investigated using both the classical Astrup technique and a newly developed titration technique. In both feeding scenarios, values were found to be similar to the values known for Ringer solution and human blood. The data show that SCFA- and HCO3- are the primary buffers in ruminal fluid and that at physiological levels of ruminal pH, HCO3- is almost completely converted to CO2, which leaves with eructation. This mechanism ensures both an efficient elimination of protons from the rumen, and the maintenance of the concentration gradient driving HCO3- secretion across the ruminal epithelium. Finally, the concept of base excess was introduced for ruminal fluid for the first time. The purpose of the second part of the present thesis was to identify and characterize possible transport proteins mediating the absorption of ammonium by the ruminal epithelium. Recent work shows that in vitro, ruminal transport of Na+ and NH4+ can be stimulated by certain agonists of the transient receptor potential family (TRP), and that the ruminal epithelium expresses mRNA for the bovine analogue of TRPV3 (bTRPV3) as a suitable candidate gene. The current thesis demonstrates that these modulators also stimulate the absorption of the essential nutrient Ca2+ in isolated ruminal epithelium in a dose dependent manner (Paper 2, Rosendahl et al., 2016). In a second step, the bTRPV3 channel was overexpressed in HEK-293 cells and characterized via the whole cell and single channel configuration of the patch clamp technique and via intracellular calcium imaging (Paper 3, Schrapers et al., 2018). It emerged that this channel reflects the properties of the conductance found in the native ruminal epithelium: the bTRPV3 conducts various cations, and the conductance of monovalent cations is modulated by the divalent cations and by TRPV3 agonists such as menthol and thymol. The conductance of different cations was measured using both the whole cell and single channel patch clamp technique, which revealed decreasing permeabilities in the order of NH4+ > Na+ > Mg2+ > Ca2+ > NMDG+. Furthermore, the application of various TRPV3 agonists increased Na+, NH4+ and K+ currents in the whole cell patch clamp configuration. Using intracellular calcium imaging, an increase in calcium influx after the addition of menthol could subsequently be found. The bovine TRPV3 should thus play an important role in mediating the ruminal transport of physiologically relevant cations such as Na+, K+, NH4+ and Ca2+. In summary, this thesis - determined the buffering constants for the bicarbonate buffer system in ruminal fluid for the first time, - demonstrated that TRP channel agonists can stimulate transport of Ca2+ across the native ruminal epithelium in vitro and - characterized the bovine representative of TRPV3 as an ion channel suitable for mediating the transport of Na+, K+ and NH4+ and Ca2+ across the rumen.Weniger anzeigen
The major aims of this thesis were to describe how arbuscular mycorrhizal (AM) fungal communities vary with depth in agricultural land, and to gain insights into AM fungal community assemblage processes in subsoil. In chapter 1 I introduce basic aspects of AM fungal biology, review existing literature on the topic of this thesis and introduce the molecular methodology used in my studies. Chapter 2 and its appendices provide highthroughput sequencing evidence for the differences in AM fungal community composition in top- and subsoil, such as for the existence of phylotypes exclusively found in subsoil. As compared to topsoil, studied subsoil communities are less species rich, less even and have higher community turnover. However, they are not just a subset of topsoil communities and harbor unique taxa. In chapter 3 a top- subsoil mixing event is studied to trace the fate of subsoil phylotypes in topsoil. Here we observe the inability of these subsoil phylotypes to persist in topsoil, and interpret this as evidence for subsoil specialization in certain AM fungal taxa. Chapter 4 discusses the potential roles of subsoil AM fungi in agriculture, with a focus on sustainability and climate smart approaches. The major potential roles identified concern the access to greater nutrient and water pools, the resistance of the system to unfavorable conditions in topsoil, and the avoidance of nutrient leaching and greenhouse gas emissions. We also point out future research needs in this field. Chapter 5 puts the results of this thesis in the broader context of the literature, summarizing the conclusions 97 of previous chapters. In this chapter I also introduce ideas on AM fungal growth strategies and implications of subsoil AM fungi for the understanding of AM fungal biogeography.Weniger anzeigen
Floral nectar offers a unique niche as habitat for microorganisms. The fluid nectar environment is characterized by a high sugar-concentration, a short flower lifetime and regular nectar depletion and replenishment caused by nectar-foraging pollinators. Microorganisms that live in floral nectar must resist high osmotic pressure, adapt quickly to new environmental conditions, have fast growth rates and manage frequent dispersal to new habitats. Besides generalist bacterial and fungal species that are also known from other sources, there are three yeast species that are almost exclusively found in floral nectar and which are called nectar yeasts: Metschnikowia reukaufii, M. gruessii and Candida rancensis. They can affect their environment by changing nectar chemistry, scent, flower temperature and, as a result, even pollinator behavior. The ecology of nectar yeasts is of interest because of their application as a microbial model system for ecological questions and their potential to change nectar quality and pollinator behavior. The pollinator has a very special role in the ecology of nectar yeasts as it collects nectar, but also triggers the production of fresh nectar, acts as dispersal pathway for microorganisms and is most likely an unintentional predator when yeasts are swallowed with nectar. The interaction between nectar yeasts and pollinators includes the effects of yeasts on pollinators and vice versa and their dependencies. This thesis focusses on the effects of pollinators on nectar yeasts, mainly by the mechanism of passive dispersal. To understand local population dynamics of nectar yeasts in single flowers and their stepwise dispersal from flower to pollinator and back to flower, I conducted laboratory experiments with honeybees and artificial flowers and applied an ecological modelling approach (Chapter 1). In the second chapter I describe my investigation of yeast dispersal and metacommunity characteristics under natural conditions in the Uckermark region (Brandenburg, Germany). Finally, I targeted the open question about the overwintering strategy of nectar yeasts in my last chapter, where I tested if yeasts can overwinter with bees (Chapter 3). In chapter one I attempted to elucidate the conditions under which nectar yeasts reach cell densities with ecological effects. My first finding was that pollination frequency must be in a beneficial range: too few pollination events reduce yeast inoculation rate and too many strongly reduce local yeast population size. Second, nectar yeasts need traits that ensure at least an intermediate growth rate and an intermediate fraction of yeasts remaining in the flower to compensate for frequent decimation events. Furthermore, I measured that only one out of a thousand cells from a local yeast population reaches the next flower with a pollinator. Those findings suggest that in systems with frequent disturbances, a trait combination of an intermediate persistence ability and intermediate growth rate is optimal rather than maximizing either trait alone. Investigations of pollinators and flowers from three common tree species in the Uckermark region (Chapter 2) revealed that floral yeast species composition was similar to yeasts dispersed by social insects and dissimilar to yeasts dispersed by solitary insects. Bumblebees and honeybees transported the most nectar-yeasts, wild bees and wasps the most insect-associated yeast species, and sawflies the most transient yeast species. I found strong decrease for yeasts specialized on insects and their nests from pollinator to flower. The results show that the flower visit frequency of the pollinator community plays an important role in determining the species richness and the overall species abundance of the yeasts in flowers, whereas local processes like environmental filtering effects mainly shape the yeast species composition. This approach offers new insights into the role of ecological filters during the dispersal and colonization processes of metacommunities and shows that nectar yeasts offer a unique model system to study the passive dispersal of communities. In the overwintering experiments with bees I did not find any isolates of specialized nectar yeast species after winter (Chapter 3). However, we found other fungi and yeast species which are known to colonize nectar but are not restricted to the nectar habitat. Some of those occur in very high abundance in floral nectar and are strong competitors with nectar yeasts in floral nectar. Thus, the question of where nectar yeasts overwinter remains open, but we can exclude bees as main vector. Instead, bees offer an overwintering pathway for competitors of nectar yeasts. This thesis contributes to our fundamental knowledge about nectar yeast ecology and offers insights into several biotic interactions between pollinating insects and yeasts living in floral nectar. I show here that nectar yeasts, from local populations to metacommunities, are strongly regulated by the density and species composition of the pollinator community.Weniger anzeigen
Presynaptic membranes are covered by protein scaffolds that are formed from few conserved families of extended proteins: ELKS/Bruchpilot family, RIM-BP, (M)Unc13, Liprin-α, Syd-1 and the RIM-superfamily including the mammalian proteins Piccolo, Bassoon. These scaffolds regulate the docking and priming of synaptic vesicles at the active zones (AZ) and thus control information transfer. Scaffold components must be safely transported along the axon before being integrated into the scaffold upon their arrival at active zone membranes. In an “early” assembly the scaffold proteins Syd-1 and Liprin-α predefine the synaptic vesicle release sites together with Neurexin and recruit the “late” scaffold components, particularly Bruchpilot and RIM-BP, to assemble the mature AZ scaffold. Neither the structural rules, by which these AZ scaffolds are transported and assembled, nor how the scaffolds exactly support AZ functions are presently well understood. In Drosophila, the integrity of the active zone scaffold depends particularly on the large core scaffold proteins Bruchpilot and RIM-BP. During my PhD work, I conducted a comprehensive yeast-two hybrid (Y2H) analysis that covered 135 constructs of 35 known AZ proteins. The protein-protein interaction network generated from these data provide a profound basis on interacting domains/ regions within the AZ scaffold. Based on the Y2H results, I identified specific serine residues in the N-terminus of Bruchpilot as a substrate of the SRPK79D kinase. In vivo analysis of site specific mutations by the Sigrist group confirmed that phosphorylation of these serine residues acts as a master switch in the transport of the “late” scaffold components Bruchpilot, RIM-BP and Unc13A. Furthermore, the Y2H approach provides evidence on the interaction of the major scaffold proteins Bruchpilot and RIM-BP and explains the isoform specific co-localization of Unc13A to the “late” scaffold while Unc13B co-localize with the “early” scaffold. I characterized important domains and interactions of the large scaffold protein RIM BP at a molecular level by solving corresponding crystal structures. The C-terminal SH3-II and SH3-III domains in RIM-BP bind several PXXP motifs in other AZ proteins while no interactions were identified for SH3-I. SH3-II and SH3-III binding to the transport adaptor Aplip1 is several fold stronger compared to other interactions and is of utmost importance for the transport of the “late” scaffold components. The crystal structure of the central FN-III array in RIM-BP suggests a potential hinge region or a preformed binding site by the three FN-III domains. Furthermore, I crystallized and characterized the binding of Spinophilin and the “early” scaffold component Syd-1 to the transmembrane protein Nrx-1. The Interaction of Spinophilin and Syd-1 with Nrx-1 regulates the assembly and proper localization of the mature AZ scaffold at the synaptic terminal.Weniger anzeigen
Seit 2003 wurde den Ländern in Form der Bildungsstandards für bestimmte Fächer (beispielsweise Mathematik, Deutsch) ein bundesweit einheitlicher Referenzrahmen zur Verfügung gestellt um die Leistungen ihrer Schülerinnen und Schüler einzuordnen (KMK, 2016). Insbesondere bildungsstandardbasierte Tests ‒ in Form der Vergleichsarbeiten (VERA) ‒ sind an Schulen weit verbreitet. So sind Lehrkräfte der 3. und 8. Jahrgangsstufe öffentlicher Schulen in Deutschland dazu verpflichtet, jährlich in mindestens einem Fach die VERA Tests für ihre insgesamt etwa 1.4 Millionen Schülerinnen und Schüler durchzuführen (KMK, 2012 Fassung von 2018; Statistisches Bundesamt, 2017). Auf der Grundlage der VERA-Tests erhalten Lehrkräfte Leistungsinformationen auf der Schul-, Klassen- und Individualebene, welche primär für die Unterrichts- und Schulentwicklung genutzt werden sollen (KMK, 2015). Die Bildungsstandards sollen „fachliche und fachübergreifende Basisqualifikationen [formulieren], die für die weitere schulische und berufliche Ausbildung von Bedeutung sind und die anschlussfähiges Lernen ermöglichen.“ (KMK, 2004, S. 7). Dieser Anspruch impliziert, dass auf Grundlage der Testergebnisse zentrale Kriterien des Schulerfolgs vorhersagbar sein sollten. Es existierte lediglich eine Studie (Graf, Harych, Wendt, Emmrich & Brunner, 2016), die die Prognosegüte bildungsstandardbasierter Tests explizit untersucht hat.
Infolge dessen wurde die übergreifende Forschungsfrage untersucht, inwiefern bildungsstandardbasierte Mathematik- und Deutschtests (im Lesen) geeignet sind, den zukünftigen schulischen Erfolg von Schülerinnen und Schüler – fokussiert auf spätere Schulhalbjahresnoten und bildungsstandardbasierte Testleistungen im selben Fach – vorherzusagen.
Die zentralen Befunde der vorliegenden Dissertation lassen sich wie folgt zusammenfassen: (1) Die Prognosegüte auf bis zu 5 Jahre spätere Testleistungen und Noten ist vergleichbar mit jener für kommerziell erhältliche Schulleistungstests. (2) Bildungsstandardbasierte Tests haben einen inkrementellen prognostischen Mehrwert gegenüber Schulhalbjahresnoten auf bis zu 5 Jahre spätere Testleistungen und Noten. (3) Die Ausprägung der Prognosegüte bildungsstandardbasierter Tests und deren inkrementeller prognostischer Mehrwert variiert zum Teil zwischen den Schulen. An den meisten Schulen liefern die bildungsstandardbasierten Tests jedoch einen Informationsgewinn zur Prognose. (4) Bildungsstandardbasierte Tests können im Sinne eines Screenings eingesetzt werden, um die Identifikation von Schülerinnen und Schüler zu verbessern, die bis zu 5 Jahre spätere Bildungsergebnisse in Form von bildungsstandardbasierten Testleistungen und Noten verfehlen.
Damit wird ein Beitrag zu bestehenden Forschungsdesideraten in Deutschland geleistet, die nicht nur für bildungsstandardbasierte Tests bestehen sondern ebenso für standardisierte Schulleistungstests im Allgemeinen. Darüber hinaus werden verschiedene Ansätze diskutiert, anhand derer zukünftig die Validierung und Implementierung von VERA Tests im Sinne einer formativen Leistungsmessung an Schulen gefördert werden könnte.Weniger anzeigen
Rivers and their adjacent riparian zones are locations of high levels of biodiversity and are well known for their enhanced rates of important biogeochemical processes. Despite their small total area, rivers contribute disproportionally to regional carbon fluxes and riparian zones are hotspots of terrestrial denitrification. Microorganisms drive these biogeochemical processes as well as serve as the basis of brown food webs and contribute to physical processes such as sediment flocculation and soil aggregation. Despite the importance of microbial communities in rivers and riparian systems, they are relatively understudied in comparison to other riverine organisms. This doctoral work investigates microbial community structure and function at the aquatic/terrestrial interface. First, a theoretical work based on the newly proposed concept of microbial community coalescence explores the potential consequences of environmental mixing on lotic and riparian microbial community structure. This work takes a catchment-scale perspective of microbial community assembly across ecosystem boundaries. Next, results of a field study conducted across nine rivers in the UK are presented, providing insight about the influence of chemical, hydrological and spatial drivers on sediment fungal community structure. This provides a sub-catchment scale view of lotic fungal diversity. The final chapter details results of an experimental study investigating the influence of collembolans, ubiquitous soil organisms, on the production of the greenhouse gas N2O. This work explores the effects of biotic-scale processes on ecosystem functioning. We reviewed field studies investigating environmental mixing processes and found evidence that environmental mixing influences microbial community structure in some compartments, such as headwaters and estuaries. The application of the microbial community coalescence concept in rivers may increase the amount of variance explained between observed local communities. Despite a rich body of literature about lotic fungal decomposer communities inhabiting leaf litter, very few studies investigated general fungal diversity. Our investigation of sediment fungal communities revealed highly diverse communities that were differentiated by underlying geology. Hydrological and chemical variables explained some of the differences between microbial communities, while spatial variables were less important. Finally, we conducted an experimental study to investigate the microbial-driven process of denitrification – an anaerobic nitrogen cycling process that produces N2 and N2O, a greenhouse gas. We found the different species of the ubiquitous soil organism Collembola affect the proportion of N2O that is produced as an end-product of denitrification and that this is related to shifts in soil nitrate concentrations. Together, this work reports findings from several under-investigated areas of microbial structure and functioning in rivers, soils and across their interface at three different scales. Our results provide insight about patterns of riverine microbial biodiversity through application of a new conceptual framework that may improve explanatory power and through a field investigation that reveals the relative importance of spatial and environmental drivers. Our field investigation was one of the first studies in Europe to apply next-generation sequencing to general fungal communities in rivers. We also provide evidence that denitrification is impacted by the presence of soil microarthropods, organisms with highly diverse communities in riparian zones. As riverine systems are simultaneously vital for ecosystem function and highly threatened by anthropogenic activity, there is an urgent need for fundamental knowledge of lotic biodiversity patterns and their relationship with function to inform conservation and restoration efforts.Weniger anzeigen
Shale is a complex medium composed of clay, other mineral phases and pore space. The combined elastic properties of these components control the effective (anisotropic) properties of the composite solid. Deformation of the compliant porosity (e.g. micro-cracks, joints, grain boundary domains, faults) impacts the relationship between effective stress and rock elasticity. This leads to nonlinear stress dependency of seismic velocities and seismic anisotropy. Such phenomenon is often observed for brittle and semi-brittle rocks like shales or other siliciclastic sediments. Description and understanding of this relationship is important for any time-lapse geophysical or geo-hazard modelling.
This thesis presents the experimental measurements and the theoretical modelling of the stress-dependent elasticity. Such a combination enables a direct comparison and validation of the theoretical approach. The porosity deformation approach is used for a physical interpretation of the stress-dependent seismic velocities. The main objective of this thesis was to validate the applicability of the theoretical approach on the experimentally obtained data. This includes analysis of the special role of the compliant porosity and its influence on the stress-dependent elasticity. For this purpose were studied various shale samples under uniaxial and triaxial stress conditions. Two of the studied samples were saturated and measured under drained loading conditions. The samples have either vertical transverse isotropy or initial horizontal transverse isotropy, and one of the samples was initially orthorhombic. These samples were loaded and their elastic properties were measured during the loading. The strain gauges measured the deformation and the piezoelements simultaneously measured the ultrasonic velocities. Thirteen conducted experiments provide a comprehensive data bank of the elastic parameters. The value of this data bank is enhanced by the mineralogical description of studied samples, including the thin section analysis and the density measurements.
The first part of the thesis introduces the theoretical background and the theoretical approaches, which were applied in the frame of this work. The second part of the thesis includes experiments under the uniaxial loading conditions and application of the theory on the obtained data sets. In this part were studied four anisotropic samples. Finally, the third part presents results of experiments under the triaxial loading conditions and an example of the application of the theory on the obtained data set. Five triaxially loaded samples include dry and saturated rocks with different initial anisotropy.
The interpretation and analysis of the laboratory measurements initiated development of additional theoretical approaches. One of them is the constant anellipticity approach and it is used for the estimation of the off-axis (under an inclination to the symmetry axis) velocity depending on the stress. Another approach is called: "orthorhombic anisotropy due to an imperfect disorder" and it is a qualitative explanation of the orthorhombic stiffness tensor observed for a visually layered sample. Application of these approaches completed the experimentally obtained data sets.
The collection of the experimental data bank with contribution of the theoretical estimations made possible application of the porosity deformation approach. This approach formulates stress-dependence of the velocities via stress-induced deformation of the pore space. The closure of the compliant (crack-like) porosity impacts the stress sensitivity of the velocities, and the shape of this stress-dependence is nonlinear. Hereby, the physical non-linearity is assumed to be controlled by the compliant pore space deformation and the geometrical non-linearity is considered to be negligible. The key parameters within the theory are the porosity tensor and the tensor of stress sensitivity. The former is anisotropic and the latter is assumed to be isotropic (according to the latest extension of the theory).
In the frame of this study, the theoretical modelling validates the applicability of the porosity deformation approach, and developed further understanding of the key parameters, their influence on the stress-dependency and their mutual relations. It was shown, that the uniaxial stress changes the anisotropy, but does not impact the anellipticity parameter. The study demonstrates the distinct influence of stiff and compliant porosities on the stress-sensitivity of the elastic properties. Particularly, the modelling of the uniaxial experiments validate the different deformation mechanisms for the stiff and compliant porosities, depending on the direction of the stress application. The modelling of the triaxial data set approved universality of proposed theoretical description and provides an opportunity for a prediction of the stress-dependent elasticity.Weniger anzeigen
Zusammenfassung: Vorliegende Arbeit untersucht Einsatz und Wirken der Allegorie im filmischen Werk Pier Paolo Pasolinis und legt dabei besonderes Augenmerk auf das Wechselspiel von textueller Abstraktion und filmischer Konkretion. In der kritischen Literatur zu Pasolinis filmischem Werk fällt der Begriff der Allegorie häufig. Doch obwohl die Allegorie als eine von Pasolinis grundlegenden poetischen Figuren erkannt wird, werden Begriff und Einsatz der Allegorie kaum näher analysiert. Dies holt diese Arbeit nach und setzt damit zugleich an jenem Aspekt von Pasolinis Filmen an, der nach wie vor als einer der interessantesten seines Werkes gilt: Pasolinis außergewöhnliche Zusammenführung einer überladenen, exponierten Zeichenhaftigkeit auf der einen Seite mit einer irreduziblen und emphatischen Körperlichkeit auf der anderen. Ausgehend von einem Überblick über die Geschichte der Allegorie und ihrer kontroversen Bestimmungen in Kunst-, Literatur- und Filmwissenschaften, arbeite ich im ersten Kapitel ein für den Film geeigneten Allegoriebegriff heraus. Darauf folgt eine Untersuchung von Pasolinis filmtheoretischen Schriften nach Anschlusspunkten für eine allegorische Praxis. Detaillierte Analysen der Filme Accattone (1961), Uccellacci e Uccellini (1966) und Porcile (1969) zeigen anschließend die Konsistenz, mit der sich Pasolini der Allegorie bedient hat, und geben zugleich Einblick in die Bandbreite, in der die Allegorie im Film wirken kann.
Abstract: This dissertation examines the allegorical practice in the films of Pier Paolo Pasolini, paying special attention to the question of textual abstraction and filmic concreteness. While critics often use the term allegory or allegorical when discussing Pasolini’s films, and even acknowledge the fundamentally allegorical nature of his poetical outlook in general, they rarely engage further in what this actually means. The allegorical mode more often than not is taken as a known term or, when explained further, reduced to only some of its aspects. In the following, I will start with a historical overview of the practice and aesthetic discussions of allegory and distill from it a definition of allegorical practice suited particularly to film. I will then analyze to what extent Pasolini’s own writings on cinema can be seen to reflect his allegorical practice. Detailed analyses of the films Accattone (1961), Uccellacci e Uccellini (1966) und Porcile (1969) subsequently show how consistently Pasolini employed allegory, and how differently it can be put into filmic play.Weniger anzeigen
This dissertation addresses the self of people with everyday multiple language use. As the self arises from the social interactions of everyday life, we assume that everyday multiple language use is reflected in the representation of the self. Conducting five empirical studies, we investigate our theoretical assumptions about a language-dependent self-representation and its positive emotional and motivational consequences. In Study 1 and Study 2, we conducted secondary analyses of existing data on bilingual immigrant school students in Germany to investigate the impact of everyday multiple language use on spontaneous accessibility of self-knowledge. Findings from Study 1 showed that for students who typically speak German only when at school but not when at home, self-knowledge bound to the school-context was more easily accessible and self-knowledge bound to the home-context less easily accessible than for students speaking German across contexts. Analogously, findings from Study 2 showed that students who typically speak German only when at school accessed two more distinguishable sources of self-esteem, in terms of affective components of self-knowledge related to the school and family context, than students who speak German also when at home, when asked in the German-speaking context of the school. In order to more directly assess the extent to which individuals’ different self-aspects are represented in different languages, i.e. compartmentalized along language lines, we introduce a newly developed bilingual version of a self-descriptive trait sorting task which we test with school students speaking English and Norwegian in Study 3. Applying the newly introduced procedure in Study 4, we assess the extent of compartmentalization along language lines in international university students who due to staying abroad currently used multiple languages in everyday life and examined the relation to their affective response towards negative bogus feedback. Findings revealed that participants’ variation in self-esteem was small when participants had chosen traits in both of their languages for their self-description in comparison to participants who had used traits in one language only in the bilingual trait sorting task. Findings from an experiment presented in Study 5, showed how accessing self-knowledge in an open self-description task in a language other than German helped participants of an online survey to buffer self-esteem threats caused by negative bogus feedback and, consequently, showed higher levels of self-esteem and more motivation to work on a second test than participants who described themselves in German after having received negative feedback in German. Taken together, our findings indicate that language offers an organizing principle for self-knowledge representation, which positively effects emotion and motivation in self-threatening situations. Based on our findings, we propose that everyday multiple language use should be considered as a potential resource for the self and discuss possible implications of our conclusion regarding theory and practice.Weniger anzeigen