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Protected cultivation in greenhouses or polytunnels offers the potential for sustainable production of high-yield, high-quality vegetables. This is related to the ability to produce more on less land and to use resources responsibly and efficiently. Crop yield has long been considered the most important factor. However, as plant-based diets have been proposed for a sustainable food system, the targeted enrichment of health-promoting plant secondary metabolites should be addressed. These metabolites include carotenoids and flavonoids, which are associated with several health benefits, such as cardiovascular health and cancer protection.
Cover materials generally have an influence on the climatic conditions, which in turn can affect the levels of secondary metabolites in vegetables grown underneath. Plastic materials are cost-effective and their properties can be modified by incorporating additives, making them the first choice. However, these additives can migrate and leach from the material, resulting in reduced service life, increased waste and possible environmental release. Antifogging additives are used in agricultural films to prevent the formation of droplets on the film surface, thereby increasing light transmission and preventing microbiological contamination.
This thesis focuses on LDPE/EVA covers and incorporated antifogging additives for sustainable protected cultivation, following two different approaches. The first addressed the direct effects of leached antifogging additives using simulation studies on lettuce leaves (Lactuca sativa var capitata L). The second determined the effect of antifog polytunnel covers on lettuce quality. Lettuce is usually grown under protective cover and can provide high nutritional value due to its carotenoid and flavonoid content, depending on the cultivar.
To study the influence of simulated leached antifogging additives on lettuce leaves, a GC-MS method was first developed to analyze these additives based on their fatty acid moieties. Three structurally different antifogging additives (reference material) were characterized outside of a polymer matrix for the first time. All of them contained more than the main fatty acid specified by the manufacturer. Furthermore, they were found to adhere to the leaf surface and could not be removed by water or partially by hexane.
The incorporation of these additives into polytunnel covers affects carotenoid levels in lettuce, but not flavonoids, caffeic acid derivatives and chlorophylls. Specifically, carotenoids were higher in lettuce grown under polytunnels without antifog than with antifog. This has been linked to their effect on the light regime and was suggested to be related to carotenoid function in photosynthesis.
In terms of protected cultivation, the use of LDPE/EVA polytunnels affected light and temperature, and both are closely related. The carotenoid and flavonoid contents of lettuce grown under polytunnels was reversed, with higher carotenoid and lower flavonoid levels. At the individual level, the flavonoids detected in lettuce did not differ however, lettuce carotenoids adapted specifically depending on the time of cultivation. Flavonoid reduction was shown to be transcriptionally regulated (CHS) in response to UV light (UVR8). In contrast, carotenoids are thought to be regulated post-transcriptionally, as indicated by the lack of correlation between carotenoid levels and transcripts of the first enzyme in carotenoid biosynthesis (PSY) and a carotenoid degrading enzyme (CCD4), as well as the increased carotenoid metabolic flux. Understanding the regulatory mechanisms and metabolite adaptation strategies could further advance the strategic development and selection of cover materials.
Relativistic pair beams produced in the cosmic voids by TeV gamma rays from blazars are expected to produce a detectable GeV-scale cascade emission missing in the observations. The suppression of this secondary cascade implies either the deflection of the pair beam by intergalactic magnetic fields (IGMFs) or an energy loss of the beam due to the electrostatic beam-plasma instability. IGMF of femto-Gauss strength is sufficient to significantly deflect the pair beams reducing the flux of secondary cascade below the observational limits. A similar flux reduction may result in the absence of the IGMF from the beam energy loss by the instability before the inverse Compton cooling. This dissertation consists of two studies about the instability role in the evolution of blazar-induced beams.
Firstly, we investigated the effect of sub-fG level IGMF on the beam energy loss by the instability. Considering IGMF with correlation lengths smaller than a few kpc, we found that such fields increase the transverse momentum of the pair beam particles, dramatically reducing the linear growth rate of the electrostatic instability and hence the energy-loss rate of the pair beam. Our results show that the IGMF eliminates beam plasma instability as an effective energy-loss agent at a field strength three orders of magnitude below that needed to suppress the secondary cascade emission by magnetic deflection. For intermediate-strength IGMF, we do not know a viable process to explain the observed absence of GeV-scale cascade emission and hence can be excluded.
Secondly, we probed how the beam-plasma instability feeds back on the beam, using a realistic two-dimensional beam distribution. We found that the instability broadens the beam opening angles significantly without any significant energy loss, thus confirming a recent feedback study on a simplified one-dimensional beam distribution. However, narrowing diffusion feedback of the beam particles with Lorentz factors less than 1e6 might become relevant even though initially it is negligible. Finally, when considering the continuous creation of TeV pairs, we found that the beam distribution and the wave spectrum reach a new quasi-steady state, in which the scattering of beam particles persists and the beam opening angle may increase by a factor of hundreds. This new intrinsic scattering of the cascade can result in time delays of around ten years, thus potentially mimicking the IGMF deflection. Understanding the implications on the GeV cascade emission requires accounting for inverse Compton cooling and simulating the beam-plasma system at different points in the IGM.
The present dissertation investigates changes in lingual coarticulation across childhood in German-speaking children from three to nine years of age and adults. Coarticulation refers to the mismatch between the abstract phonological units and their seemingly commingled realization in continuous speech. Being a process at the intersection of phonology and phonetics, addressing its changes across childhood allows for insights in speech motor as well as phonological developments. Because specific predictions for changes in coarticulation across childhood can be derived from existing speech production models, investigating children’s coarticulatory patterns can help us model human speech production.
While coarticulatory changes may shed light on some of the central questions of speech production development, previous studies on the topic were sparse and presented a puzzling picture of conflicting findings. One of the reasons for this lack is the difficulty in articulatory data acquisition in a young population. Within the research program this dissertation is embedded in, we accepted this challenge and successfully set up the hitherto largest corpus of articulatory data from children using ultrasound tongue imaging. In contrast to earlier studies, a high number of participants in tight age cohorts across a wide age range and a thoroughly controlled set of pseudowords allowed for statistically powerful investigations of a process known as variable and complicated to track.
The specific focus of my studies is on lingual vocalic coarticulation as measured in the horizontal position of the highest point of the tongue dorsum. Based on three studies on a) anticipatory coarticulation towards the left, b) carryover coarticulation towards the right side of the utterance, and c) anticipatory coarticulatory extent in repeated versus read aloud speech, I deduct the following main theses:
1. Maturing speech motor control is responsible for some developmental changes in coarticulation.
2. Coarticulation can be modeled as the coproduction of articulatory gestures.
3. The developmental change in coarticulation results from a decrease of vocalic activation width.
Èto-clefts are Russian focus constructions with the demonstrative pronoun èto ‘this’ at the beginning: “Èto Mark vyigral gonku” (“It was Mark who won the race”). They are often being compared with English it-clefts, German es-clefts, as well as the corresponding focus-background structures in other languages.
In terms of semantics, èto-clefts have two important properties which are cross-linguistically typical for clefts: existence presupposition (“Someone won the race”) and exhaustivity (“Nobody except Mark won the race”). However, the exhaustivity effects are not as strong as exhaustivity effects in structures with the exclusive only and require more research.
At the same time, the question if the syntactic structure of èto-clefts matches the biclausal structure of English and German clefts, remains open. There are arguments in favor of biclausality, as well as monoclausality. Besides, there is no consistency regarding the status of èto itself.
Finally, the information structure of èto-clefts has remained underexplored in the existing literature.
This research investigates the information-structural, syntactic, and semantic properties of Russian clefts, both theoretically (supported by examples from Russian text corpora and judgments from native speakers) and experimentally. It is determined which desired changes in the information structure motivate native speakers to choose an èto-cleft and not the canonical structure or other focus realization tools. Novel syntactic tests are conducted to find evidence for bi-/monoclausality of èto-clefts, as well as for base-generation or movement of the cleft pivot. It is hypothesized that èto has a certain important function in clefts, and its status is investigated. Finally, new experiments on the nature of exhaustivity in èto-clefts are conducted. They allow for direct cross-linguistic comparison, using an incremental-information paradigm with truth-value judgments.
In terms of information structure, this research makes a new proposal that presents èto-clefts as structures with an inherent focus-background bipartitioning. Even though èto-clefts are used in typical focus contexts, evidence was found that èto-clefts (as well as Russian thetic clefts) allow for both new information focus and contrastive focus. Èto-clefts are pragmatically acceptable when a singleton answer to the implied question is expected (e.g. “It was Mark who won the race” but not “It was Mark who came to the party”). Importantly, èto in Russian clefts is neither dummy, nor redundant, but is a topic expression; conveys familiarity which triggers existence presupposition; refers to an instantiated event, or a known/perceivable situation; finally, èto plays an important role in the spoken language as a tool for speech coherency and a focus marker.
In terms of syntax, this research makes a new monoclausal proposal and shows evidence that the cleft pivot undergoes movement to the left peripheral position. Èto is proposed to be TopP.
Finally, in terms of semantics, a novel cross-linguistic evaluation of Russian clefts is made. Experiments show that the exhaustivity inference in èto-clefts is not robust. Participants used different strategies in resolving exhaustivity, falling into 2 groups: one group considered èto-clefts exhaustive, while another group considered them non-exhaustive. Hence, there is evidence for the pragmatic nature of exhaustivity in èto-clefts. The experimental results for èto-clefts are similar to the experimental results for clefts in German, French and Akan. It is concluded that speakers use different tools available in their languages to produce structures with similar interpretive properties.
Development of a CRISPR/Cas gene editing technique for the coccolithophore Chrysotila carterae
(2024)
Dentro de la cuenca intermontana de Quito-Guay llabamba de Ecuador, se han identificado y analizado en este estudio, cinco depósitos coluviales inusualmente grandes de antiguos deslizamientos. El gran deslizamiento rotacional MM-5 Guayllabamba es el más extenso, con un volumen de 1183 millones de m3. Las mega avalanchas de escombros MM-1 Conocoto, MM-3 Oyacoto, y MM-4 San Francisco fueron desencadenadas originalmente por una ruptura inicial que estuvo asociada a un deslizamiento rotacional, los depósitos correspondientes tienen volúmenes entre 399 a 317 millones de m3. Finalmente, el depósito de menor volumen, el deslizamiento rotacional y caída de detritos MM-2 Batán, tiene un volumen de 8,7 millones de m3. En esta tesis, se realizó un estudio detallado de estos grandes movimientos en masa utilizando métodos neotectónicos y lito-tefrostratigráficos para comprender las condiciones geológicas y geomorfológicas de contorno que podrían ser relevantes para desencadenar estos movimientos en masa. La parte neotectónica del estudio se basó en el análisis geomorfológico cualitativo y cuantitativo de estos grandes depósitos de movimientos en masa, a través de la caracterización estructural de anticlinales ubicados al este de la subcuenca de Quito y sus flancos colapsados que constituyen las áreas de ruptura. Esta parte del análisis fue además apoyada por la aplicación de diferentes índices morfométricos para revelar procesos de evolución del paisaje forzados tectónicamente que pueden haber contribuido a la generación de movimientos en masa. La parte lito-tefrostratigráfica del estudio se basó en el análisis de las características petrográficas, geoquímicas y geocronológicas de los horizontes del suelo y de las cenizas volcánicas intercaladas, con el objetivo de restringir la cronología de los eventos individuales de movimientos en masa y su posible de correlación. Los resultados se integraron en esquemas cronoestratigráficos utilizando superficies de ruptura, relaciones transversales y de superposición de depósitos de deslizamiento y estratos posteriores para comprender los movimientos en masa en el contexto tectónico y temporal del entorno de la cuenca intermontana, así como para identificar los mecanismos desencadenantes de cada evento. El movimiento en masa MM-5 Guayllabamba es el resultado del colapso de la ladera suroeste del volcán Mojanda y fue desencadenado por la interacción de condiciones geológicas y morfológicas hace aproximadamente 0,81 Ma. El primer episodio de avalancha de escombros de los movimientos en masa MM-3 Oyacoto y MM-4 San Francisco podría estar relacionado con condiciones tanto geológicas como morfológicas, dadas las rocas altamente fracturadas y el levantamiento del anticlinal Bellavista-Catequilla que posteriormente fue inciso al pie de la ladera por la erosión fluvial. Este primer episodio de colapso probablemente ocurrió alrededor de los 0,8 Ma. El movimiento en masa MM-2 Batán posiblemente también fue desencadenado por una combinación de condiciones geológicas y morfológicas, asociadas a una reducción de los esfuerzos litostáticos que afectaron a las formaciones Chiche y Machángara y a un aumento de los esfuerzos de cizalla durante procesos de socavación fluvial lateral en los flancos de las áreas de origen. Esto apunta a un proceso vinculado entre la erosión fluvial y los procesos de levantamiento asociados a la evolución del anticlinal El Batán-La Bota que podría haber ocurrido entre 0,5 y 0,25 Ma. La voluminosa avalancha de escombros MM-1 Conocoto, así como el segundo episodio de avalancha de escombros que generó los movimientos en masa MM-3 Oyacoto y MM-4 San Francisco, fueron provocados por el colapso gravitacional de las formaciones Mojanda y Cangahua que se caracterizan por la intercalación de cenizas volcánicas. La falla del flanco oriental de los anticlinales probablemente estuvo asociada al incremento de la humedad disponible relacionada con las variaciones climáticas regionales del Holoceno. Los resultados de la cronología de los paleosuelos combinados con los datos cronoestratigráficos y paleoclimáticos regionales sugieren que estas avalanchas de escombros se desencadenaron entre 5 y 4 ka.
La tectónica activa ha modelado los rasgos morfológicos de la cuenca intermontana Quito-Guayllabamba. El desencadenamiento de movimientos en masa en este ambiente está asociado a rupturas en litologías del Pleistoceno (sedimentos lacustres, depósitos aluviales y volcánicos) sometidas a procesos de deformación, actividad sísmica y episodios superpuestos de variabilidad climática. El Distrito Metropolitano de Quito es parte integral de este complejo entorno y de las condiciones geológicas, climáticas y topográficas que continúan influyendo en el espacio geográfico urbano dentro de esta cuenca intermontana. La ciudad de Quito comprende el área de mayor consolidación urbana incluyendo las subcuencas de Quito y San Antonio, con una población de 2,872 millones de habitantes, lo que refleja la importancia del estudio de las amenazas geológicas y climáticas inherentes a esta región.
Optimizing power analysis for randomized experiments: Design parameters for student achievement
(2024)
Randomized trials (RTs) are promising methodological tools to inform evidence-based reform to enhance schooling. Establishing a robust knowledge base on how to promote student achievement requires sensitive RT designs demonstrating sufficient statistical power and precision to draw conclusive and correct inferences on the effectiveness of educational programs and innovations. Proper power analysis is therefore an integral component of any informative RT on student achievement. This venture critically hinges on the availability of reasonable input variance design parameters (and their inherent uncertainties) that optimally reflect the realities around the prospective RT—precisely, its target population and outcome, possibly applied covariates, the concrete design as well as the planned analysis. However, existing compilations in this vein show far-reaching shortcomings.
The overarching endeavor of the present doctoral thesis was to substantively expand available resources devoted to tweak the planning of RTs evaluating educational interventions. At the core of this thesis is a systematic analysis of design parameters for student achievement, generating reliable and versatile compendia and developing thorough guidance to support apt power analysis to design strong RTs. To this end, the thesis at hand bundles two complementary studies which capitalize on rich data of several national probability samples from major German longitudinal large-scale assessments.
Study I applied two- and three-level latent (covariate) modeling to analyze design parameters for a wide spectrum of mathematical-scientific, verbal, and domain-general achievement outcomes. Three vital covariate sets were covered comprising (a) pretests, (b) sociodemographic characteristics, and (c) their combination. The accumulated estimates were additionally summarized in terms of normative distributions.
Study II specified (manifest) single-, two-, and three-level models and referred to influential psychometric heuristics to analyze design parameters and develop concise selection guidelines for covariate (a) types of varying bandwidth-fidelity (domain-identical, cross-domain, fluid intelligence pretests; sociodemographic characteristics), (b) combinations quantifying incremental validities, and (c) time lags of 1- to 7-year-lagged pretests scrutinizing validity degradation. The estimates for various mathematical-scientific and verbal achievement outcomes were meta-analytically integrated and employed in precision simulations.
In doing so, Studies I and II addressed essential gaps identified in previous repertoires in six major dimensions: Taken together, this thesis accumulated novel design parameters and deliberate guidance for RT power analysis (1) tailored to four German student (sub)populations across the entire school career from Grade 1 to 12, (2) matched to 21 achievement (sub)domains, (3) adjusted for 11 covariate sets enriched by empirically supported guidelines, (4) adapted to six RT designs, (5) suitable for latent and manifest analysis models, (6) which were cataloged along with quantifications of their associated uncertainties. These resources are complemented by a plethora of illustrative application examples to gently direct psychological and educational researchers through pivotal steps in the process of RT design.
The striking heterogeneity of the design parameter estimates across all these dimensions constitutes the overall, joint key result of Studies I and II. Hence, this work convincingly reinforces calls for a close match between design parameters and the specific peculiarities of the target RT’s research context.
All in all, the present doctoral thesis offers a—so far unique—nuanced and extensive toolkit to optimize power analysis for sound RTs on student achievement in the German (and similar) school context. It is of utmost importance that research does not tire to spawn robust evidence on what actually works to improve schooling. With this in mind, I hope that the emerging compendia and guidance contribute to the quality and rigor of our randomized experiments in psychology and education.
It is a common finding that preschoolers have difficulties in identifying who is doing what to whom in non-canonical sentences, such as (object-verb-subject) OVS and passive sentences in German. This dissertation investigates how German monolingual and German-Italian simultaneous bilingual children process German OVS sentences in Study 1 and German passives in Study 2. Offline data (i.e., accuracy data) and online data (i.e., eye-gaze and pupillometry data) were analyzed to explore whether children can assign thematic roles during sentence comprehension and processing. Executive functions, language-internal and -external factors were investigated as potential predictors for children’s sentence comprehension and processing.
Throughout the literature, there are contradicting findings on the relation between language and executive functions. While some results show a bilingual cognitive advantage over monolingual speakers, others suggest there is no relationship between bilingualism and executive functions. If bilingual children possess more advanced executive function abilities than monolingual children, then this might also be reflected in a better performance on linguistic tasks. In the current studies monolingual and bilingual children were tested by means of two executive function tasks: the Flanker task and the task-switching paradigm. However, these findings showed no bilingual cognitive advantages and no better performance by bilingual children in the linguistic tasks. The performance was rather comparable between bilingual and monolingual children, or even better for the monolingual group. This may be due to cross-linguistic influences and language experience (i.e., language input and output). Italian was used because it does not syntactically overlap with the structure of German OVS sentences, and it only overlapped with one of the two types of sentence condition used for the passive study - considering the subject-(finite)verb alignment. The findings showed a better performance of bilingual children in the passive sentence structure that syntactically overlapped in the two languages, providing evidence for cross-linguistic influences.
Further factors for children’s sentence comprehension were considered. The parents’ education, the number of older siblings and language experience variables were derived from a language background questionnaire completed by parents. Scores of receptive vocabulary and grammar, visual and short-term memory and reasoning ability were measured by means of standardized tests. It was shown that higher German language experience by bilinguals correlates with better accuracy in German OVS sentences but not in passive sentences. Memory capacity had a positive effect on the comprehension of OVS and passive sentences in the bilingual group. Additionally, a role was played by executive function abilities in the comprehension of OVS sentences and not of passive sentences. It is suggested that executive function abilities might help children in the sentence comprehension task when the linguistic structures are not yet fully mastered.
Altogether, these findings show that bilinguals’ poorer performance in the comprehension and processing of German OVS is mainly due to reduced language experience in German, and that the different performance of bilingual children with the two types of passives is mainly due to cross-linguistic influences.
Actin is one of the most highly conserved proteins in eukaryotes and distinct actin-related proteins with filament-forming properties are even found in prokaryotes. Due to these commonalities, actin-modulating proteins of many species share similar structural properties and proposed functions. The polymerization and depolymerization of actin are critical processes for a cell as they can contribute to shape changes to adapt to its environment and to move and distribute nutrients and cellular components within the cell. However, to what extent functions of actin-binding proteins are conserved between distantly related species, has only been addressed in a few cases. In this work, functions of Coronin-A (CorA) and Actin-interacting protein 1 (Aip1), two proteins involved in actin dynamics, were characterized. In addition, the interchangeability and function of Aip1 were investigated in two phylogenetically distant model organisms. The flowering plant Arabidopsis thaliana (encoding two homologs, AIP1-1 and AIP1-2) and in the amoeba Dictyostelium discoideum (encoding one homolog, DdAip1) were chosen because the functions of their actin cytoskeletons may differ in many aspects. Functional analyses between species were conducted for AIP1 homologs as flowering plants do not harbor a CorA gene.
In the first part of the study, the effect of four different mutation methods on the function of Coronin-A protein and the resulting phenotype in D. discoideum was revealed in two genetic knockouts, one RNAi knockdown and a sudden loss-of-function mutant created by chemical-induced dislocation (CID). The advantages and disadvantages of the different mutation methods on the motility, appearance and development of the amoebae were investigated, and the results showed that not all observed properties were affected with the same intensity. Remarkably, a new combination of Selection-Linked Integration and CID could be established.
In the second and third parts of the thesis, the exchange of Aip1 between plant and amoeba was carried out. For A. thaliana, the two homologs (AIP1-1 and AIP1-2) were analyzed for functionality as well as in D. discoideum. In the Aip1-deficient amoeba, rescue with AIP1-1 was more effective than with AIP1-2. The main results in the plant showed that in the aip1-2 mutant background, reintroduced AIP1-2 displayed the most efficient rescue and A. thaliana AIP1-1 rescued better than DdAip1. The choice of the tagging site was important for the function of Aip1 as steric hindrance is a problem. The DdAip1 was less effective when tagged at the C-terminus, while the plant AIP1s showed mixed results depending on the tag position. In conclusion, the foreign proteins partially rescued phenotypes of mutant plants and mutant amoebae, despite the organisms only being very distantly related in evolutionary terms.
The Central Andean region is characterized by diverse climate zones with sharp transitions between them. In this work, the area of interest is the South-Central Andes in northwestern Argentina that borders with Bolivia and Chile. The focus is the observation of soil moisture and water vapour with Global Navigation Satellite System (GNSS) remote-sensing methodologies. Because of the rapid temporal and spatial variations of water vapour and moisture circulations, monitoring this part of the hydrological cycle is crucial for understanding the mechanisms that control the local climate. Moreover, GNSS-based techniques have previously shown high potential and are appropriate for further investigation. This study includes both logistic-organization effort and data analysis. As for the prior, three GNSS ground stations were installed in remote locations in northwestern Argentina to acquire observations, where there was no availability of third-party data.
The methodological development for the observation of the climate variables of soil moisture and water vapour is independent and relies on different approaches. The soil-moisture estimation with GNSS reflectometry is an approximation that has demonstrated promising results, but it has yet to be operationally employed. Thus, a more advanced algorithm that exploits more observations from multiple satellite constellations was developed using data from two pilot stations in Germany. Additionally, this algorithm was slightly modified and used in a sea-level measurement campaign. Although the objective of this application is not related to monitoring hydrological parameters, its methodology is based on the same principles and helps to evaluate the core algorithm. On the other hand, water-vapour monitoring with GNSS observations is a well-established technique that is utilized operationally. Hence, the scope of this study is conducting a meteorological analysis by examining the along-the-zenith air-moisture levels and introducing indices related to the azimuthal gradient.
The results of the experiments indicate higher-quality soil moisture observations with the new algorithm. Furthermore, the analysis using the stations in northwestern Argentina illustrates the limits of this technology because of varying soil conditions and shows future research directions. The water-vapour analysis points out the strong influence of the topography on atmospheric moisture circulation and rainfall generation. Moreover, the GNSS time series allows for the identification of seasonal signatures, and the azimuthal-gradient indices permit the detection of main circulation pathways.
Die Arbeit „Die Bekämpfung transnationaler Kriminalität im Kontext fragiler Staatlichkeit“ widmet sich dem Phänomen grenzüberschreitend tätiger Akteure der organisierten Kriminalität die den Umstand ausnutzen, dass einige international anerkannte Regierungen nur eine unzureichende Kontrolle über Teile ihres Staatsgebietes ausüben. Es wird untersucht, weshalb der durch die internationale Staatengemeinschaft geschaffene Rechtsrahmen, zur Bekämpfung transnationaler Kriminalitätsphänomene im Kontext dieser fragilen Staaten, nicht oder nur defizitär dazu beiträgt die Kriminalitätsphänomene zu bekämpfen.
Nachdem zunächst erörtert wird, was im Rahmen der Untersuchung unter dem Begriff der transnationalen Kriminalität verstanden wird, wird der internationale Rechtsrahmen zur Bekämpfung anhand von fünf beispielhaft ausgewählten transnationalen Kriminalitätsphänomenen beschrieben. Im darauffolgenden Hauptteil der Untersuchung wird der Frage nachgegangen, weshalb dieser durch die internationale Staatengemeinschaft geschaffene Rechtsrahmen, gerade in fragilen Staaten, kaum einen Beitrag dazu leistet solchen Kriminalitätsphänomenen effektiv zu begegnen. Dabei wird festgestellt, dass die Genese des internationalen Rechtsrahmens zu einem Legitimitätsdefizit desselbigen führt. Auch die mangelhafte Berücksichtigung der speziellen Lebensrealitäten, die in vielen fragilen Staaten vorzufinden sind, wirkt sich negativ auf die Durchsetzbarkeit des internationalen Rechtsrahmens aus. Es wird dargelegt, dass unterschiedlich hohe menschenrechtliche Schutzstandards zu Normenkollisionen bei der internationalen Zusammenarbeit der Staaten führen, insbesondere im Rahmen der internationalen Rechtshilfe. Da gerade fragile Staaten häufig durch eine defizitäre menschenrechtliche Situation gekennzeichnet sind, stellt dies konsolidierte Staaten im Rahmen der Zusammenarbeit mit fragilen Staaten öfters vor Herausforderungen. Schließlich wird aufgezeigt, dass auch die extraterritoriale Jurisdiktion und somit die strafrechtliche Verfolgung transnationaler Straftaten durch Drittstaaten mit rechtlichen und praktischen Problemen einhergeht.
In einem letzten Kapitel der Arbeit wird der Frage nachgegangen, ob nicht ein alternativer Strafverfolgungsmechanismus geschaffen werden sollte, um transnationale Kriminalitätsphänomene zu verfolgen, die aus fragilen Staaten heraus begangen werden und wie ein solch alternativer Strafverfolgungsmechanismus konkret ausgestaltet sein sollte.
This study focuses on William Faulkner, whose works explore the demise of the slavery-based Old South during the Civil War in a highly experimental narrative style. Central to this investigation is the analysis of the temporal dimensions of both individual and collective guilt, thus offering a new approach to the often-discussed problem of Faulkner’s portrayal of social decay. The thesis examines how Faulkner re-narrates the legacy of the Old South as a guilt narrative and argues that Faulkner uses guilt in order to corroborate his concept of time and the idea of the continuity of the past. The focus of the analysis is on three of Faulkner’s arguably most important novels: The Sound and the Fury, Absalom, Absalom!, and Go Down, Moses. Each of these novels features a main character deeply overwhelmed by the crimes of the past, whether private, familial, or societal. As a result, guilt is explored both from a domestic as well as a social perspective. In order to show how Faulkner blends past and present by means of guilt, this work examines several methods and motifs borrowed from different fields and genres with which Faulkner narratively negotiates guilt. These include religious notions of original sin, the motif of the ancestral curse prevalent in the Southern Gothic genre, and the psychological concept of trauma. Each of these motifs emphasizes the temporal dimensions of guilt, which are the core of this study, and makes clear that guilt in Faulkner’s work is primarily to be understood as a temporal rather than a moral problem.
Assessing the impact of global change on hydrological systems is one of the greatest hydrological challenges of our time. Changes in land cover, land use, and climate have an impact on water quantity, quality, and temporal availability. There is a widespread consensus that, given the far-reaching effects of global change, hydrological systems can no longer be viewed as static in their structure; instead, they must be regarded as entire ecosystems, wherein hydrological processes interact and coevolve with biological, geomorphological, and pedological processes. To accurately predict the hydrological response under the impact of global change, it is essential to understand this complex coevolution. The knowledge of how hydrological processes, in particular the formation of subsurface (preferential) flow paths, evolve within this coevolution and how they feed back to the other processes is still very limited due to a lack of observational data.
At the hillslope scale, this intertwined system of interactions is known as the hillslope feedback cycle. This thesis aims to enhance our understanding of the hillslope feedback cycle by studying the coevolution of hillslope structure and hillslope hydrological response. Using chronosequences of moraines in two glacial forefields developed from siliceous and calcareous glacial till, the four studies shed light on the complex coevolution of hydrological, biological, and structural hillslope properties, as well as subsurface hydrological flow paths over an evolutionary period of 10 millennia in these two contrasting geologies. The findings indicate that the contrasting properties of siliceous and calcareous parent materials lead
to variations in soil structure, permeability, and water storage. As a result, different plant species and vegetation types are favored on siliceous versus calcareous parent material, leading to diverse ecosystems with distinct hydrological dynamics. The siliceous parent material was found to show a higher activity level in driving the coevolution. The soil pH resulting from parent material weathering emerges as a crucial factor, influencing vegetation development, soil formation, and consequently, hydrology. The acidic weathering of the siliceous parent material favored the accumulation of organic matter, increasing the soils’ water storage capacity and attracting acid-loving shrubs, which further promoted organic matter accumulation and ultimately led to podsolization after 10 000 years. Tracer experiments revealed that the subsurface flow path evolution was influenced by soil and vegetation development, and vice versa. Subsurface flow paths changed from vertical, heterogeneous matrix flow to finger-like flow paths over a few hundred years, evolving into macropore flow, water storage, and lateral subsurface flow after several thousand years. The changes in flow paths among younger age classes were driven by weathering processes altering soil structure, as well as by vegetation development and root activity. In the older age
class, the transition to more water storage and lateral flow was attributed to substantial organic matter accumulation and ongoing podsolization. The rapid vertical water transport in the finger-like flow paths, along with the conductive sandy material, contributed to podsolization and thus to the shift in the hillslope hydrological response.
In contrast, the calcareous site possesses a high pH buffering capacity, creating a neutral to basic environment with relatively low accumulation of dead organic matter, resulting in a lower water storage capacity and the establishment of predominantly grass vegetation. The coevolution was found to be less dynamic over the millennia. Similar to the siliceous site, significant changes in subsurface flow paths occurred between the young age classes. However, unlike the siliceous site, the subsurface flow paths at the calcareous site only altered in shape and not in direction. Tracer experiments showed that flow paths changed from vertical, heterogeneous matrix flow to vertical, finger-like flow paths after a few hundred to thousands of years, which was driven by root activities and weathering processes. Despite having a finer soil texture, water storage at the calcareous site was significantly lower than at the siliceous site, and water transport remained primarily rapid and vertical, contributing to the flourishing of grass vegetation.
The studies elucidated that changes in flow paths are predominantly shaped by the characteristics of the parent material and its weathering products, along with their complex interactions with initial water flow paths and vegetation development. Time, on the other hand, was not found to be a primary factor in describing the evolution of the hydrological response. This thesis makes a valuable contribution to closing the gap in the observations of the coevolution of hydrological processes within the hillslope feedback cycle, which is important to improve predictions of hydrological processes in changing landscapes. Furthermore, it emphasizes the importance of interdisciplinary studies in addressing the hydrological challenges arising from global change.
Food Neophilie
(2023)
Trotz der eindeutigen Vorteile einer ausgewogenen Ernährung halten sich viele Menschen weltweit nicht an entsprechende Ernährungsrichtlinien. Um angemessene Strategien zur Unterstützung einer gesundheitsfördernden Ernährung zu entwickeln, ist ein Verständnis der zugrunde liegenden Faktoren unerlässlich. Insbesondere die Gruppe der älteren Erwachsenen stellt dabei eine wichtige Zielgruppe für ernährungsbezogene Präventions- und Interventionsansätze dar. Einer der vielen Faktoren, die als Determinanten einer gesundheitsfördernden Ernährung diskutiert werden, ist die Food Neophilie, also die Bereitschaft, neue und unbekannte Lebensmittel auszuprobieren. Aktuelle Forschungsergebnisse legen nahe, dass die Food Neophilie positiv mit einer gesundheitsfördernden Ernährung in Verbindung steht, allerdings ist die bisherige Forschung in diesem Bereich äußerst begrenzt. Das Ziel der Dissertation war es, das Konstrukt der Food Neophilie sowie seine Beziehung zu gesundheitsförderndem Ernährungsverhalten im höheren Erwachsenenalter grundlegend zu erforschen, um das Potenzial der Food Neophilie für die Gesundheitsförderung älterer Erwachsener besser zu verstehen. Dabei wurde im Rahmen der ersten Publikation zunächst untersucht, wie sich das Konstrukt der Food Neophilie reliabel und valide erfassen lässt, um weiterführende Untersuchungen der Food Neophilie zu ermöglichen. Die psychometrische Validierung der deutschen Version der Variety Seeking Tendency Scale (VARSEEK) basierte auf zwei unabhängigen Stichproben mit insgesamt N = 1000 Teilnehmenden und bestätigte, dass es sich bei der Skala um ein reliables und valides Messinstrument zur Erfassung der Food Neophilie handelt. Darauf aufbauend wurde im Rahmen der zweiten Publikation die Beziehung der Food Neophilie und der Ernährungsqualität über die Zeit hinweg analysiert. Die prospektive Untersuchung von N = 960 Teilnehmenden des höheren Erwachsenenalters (M = 63.4 Jahre) anhand einer Cross-Lagged-Panel-Analyse ergab hohe zeitliche Stabilitäten der Food Neophilie und der Ernährungsqualität über einen Zeitraum von drei Jahren. Es zeigte sich zudem ein positiver querschnittlicher Zusammenhang zwischen der Food Neophilie und der Ernährungsqualität, jedoch wurde die Food Neophilie nicht als signifikante Determinante der Ernährungsqualität über die Zeit hinweg identifiziert. In der dritten Publikation wurden schließlich nicht nur die individuellen Auswirkungen der Food Neophilie auf die Ernährungsqualität betrachtet, sondern auch potenzielle dynamische Wechselwirkungen innerhalb von Partnerschaften einbezogen. Hierzu erfolgte mittels eines Actor-Partner-Interdependence-Modells eine Differenzierung potenzieller intra- und interpersoneller Einflüsse der Food Neophilie auf die Ernährungsqualität. Im Rahmen der dyadischen Analyse zeigte sich bei N = 390 heterosexuellen Paaren im höheren Erwachsenenalter (M = 64.0 Jahre) ein Dominanzmuster: Während die Food Neophilie der Frauen positiv mit ihrer eigenen Ernährungsqualität und der ihrer Partner zusammenhing, war die Food Neophilie der Männer nicht mit der Ernährungsqualität des Paares assoziiert. Insgesamt leistet die vorliegende Dissertation einen wertvollen Beitrag zum umfassenden Verständnis der Food Neophilie sowie ihrer Rolle im Kontext der Ernährungsgesundheit älterer Erwachsener. Trotz fehlender Vorhersagekraft über die Zeit hinweg deutet der positive Zusammenhang zwischen Food Neophilie und Ernährungsqualität darauf hin, dass die Fokussierung auf eine positive und neugierige Einstellung gegenüber Lebensmitteln eine innovative Perspektive für Präventions- und Interventionsansätze zur Unterstützung einer gesundheitsfördernden Ernährung älterer Erwachsener bieten könnte.
Die umfangreiche rechtswissenschaftliche Studie befasst sich mit den preußischen Staatskirchenverträgen aus der Zeit der Weimarer Republik. Diese Verträge waren Höhepunkte einer Entwicklung in Richtung größerer Freiheit und Unabhängigkeit der Kirchen vom Staat, die den Vorgängen im Reich und in anderen deutschen Ländern teils entsprach, teils zuwiderlief. Die Entwicklung folgte keiner unverrückbaren Idealvorstellung über das Verhältnis von Staat und Kirche, sondern stellte sich stets als pragmatische Reaktion auf realpolitische Probleme dar. Die Staatskirchenverträge selbst prägten die weiteren Entwicklungen in Ost und West bis zur Gegenwart.
The increasing number of known exoplanets raises questions about their demographics and the mechanisms that shape planets into how we observe them today. Young planets in close-in orbits are exposed to harsh environments due to the host star being magnetically highly active, which results in high X-ray and extreme UV fluxes impinging on the planet. Prolonged exposure to this intense photoionizing radiation can cause planetary atmospheres to heat up, expand and escape into space via a hydrodynamic escape process known as photoevaporation. For super-Earth and sub-Neptune-type planets, this can even lead to the complete erosion of their primordial gaseous atmospheres. A factor of interest for this particular mass-loss process is the activity evolution of the host star. Stellar rotation, which drives the dynamo and with it the magnetic activity of a star, changes significantly over the stellar lifetime. This strongly affects the amount of high-energy radiation received by a planet as stars age. At a young age, planets still host warm and extended envelopes, making them particularly susceptible to atmospheric evaporation. Especially in the first gigayear, when X-ray and UV levels can be 100 - 10,000 times higher than for the present-day sun, the characteristics of the host star and the detailed evolution of its high-energy emission are of importance.
In this thesis, I study the impact of stellar activity evolution on the high-energy-induced atmospheric mass loss of young exoplanets. The PLATYPOS code was developed as part of this thesis to calculate photoevaporative mass-loss rates over time. The code, which couples parameterized planetary mass-radius relations with an analytical hydrodynamic escape model, was used, together with Chandra and eROSITA X-ray observations, to investigate the future mass loss of the two young multiplanet systems V1298 Tau and K2-198. Further, in a numerical ensemble study, the effect of a realistic spread of activity tracks on the small-planet radius gap was investigated for the first time. The works in this thesis show that for individual systems, in particular if planetary masses are unconstrained, the difference between a young host star following a low-activity track vs. a high-activity one can have major implications: the exact shape of the activity evolution can determine whether a planet can hold on to some of its atmosphere, or completely loses its envelope, leaving only the bare rocky core behind. For an ensemble of simulated planets, an observationally-motivated distribution of activity tracks does not substantially change the final radius distribution at ages of several gigayears. My simulations indicate that the overall shape and slope of the resulting small-planet radius gap is not significantly affected by the spread in stellar activity tracks. However, it can account for a certain scattering or fuzziness observed in and around the radius gap of the observed exoplanet population.
Die vorliegende Arbeit untersucht Urlaubsfotografien bei Facebook und beschreibt, welche sozio-technischen Medienpraktiken sich innerhalb der Social-Media Plattform über die Fotografien vollziehen. Fotografische Praktiken sind durch aktive Handlungen und soziale Gebrauchsweisen bestimmt. Urlaubsfotografien tragen zum Beispiel zur Strukturierung von Reiserouten und Vorstellungen bei, indem genrespezifische Motive und Rahmungen mit Hilfe von Medien reproduziert und wiederholt werden. Praktiken des Zeigens, Teilens und Kommunizierens werden durch Social Plug-Ins (Like/Share Buttons) und Tagging-Funktionen auch in die Benutzeroberflächen von Facebook integriert. Dadurch werden Nutzer*innen Aktivitäten und technische Prozesse miteinander verbunden. Am Beispiel der automatischen Generierung von Urlaubsfotografien auf Geotagseiten wird gezeigt, dass Social-Tagging zur Entstehung und Aushandlung geographischer Räume und Ortsvorstellungen beiträgt. Mithilfe technischer Strukturierungen von Fotografien auf Taggingseiten werden genrespezifische Motive, fotografische Trends und Ästhetiken besonders sichtbar. Allerdings wird ihre Visualisierung auch durch algorithmische Priorisierung einzelner Inhalte mitbestimmt. Dadurch werden Urlaubsfotografien für ein fotografisches Profiling genutzt, da sie das algorithmische Erfassen und Auswerten von Nutzer*innen-Informationen ermöglichen. Die Arbeit zeigt, dass der Einsatz von Bilderkennungsverfahren und fotografischen Datenanalysen zu einer optimierten Informationsgewinnung und zu einer Standardisierung von Fotografien beiträgt.
Watershed management requires an understanding of key hydrochemical processes. The Pra Basin is one of the five major river basins in Ghana with a population of over 4.2 million people. Currently, water resources management faces challenges due to surface water pollution caused by the unregulated release of untreated household and industrial waste into aquatic ecosystems and illegal mining activities. This has increased the need for groundwater as the most reliable water supply. Our understanding of groundwater recharge mechanisms and chemical evolution in the basin has been inadequate, making effective management difficult. Therefore, the main objective of this work is to gain insight into the processes that determine the hydrogeochemical evolution of groundwater quality in the Pra Basin. The combined use of stable isotope, hydrochemistry, and water level data provides the basis for conceptualizing the chemical evolution of groundwater in the Pra Basin. For this purpose, the origin and evaporation rates of water infiltrating into the unsaturated zone were evaluated. In addition, Chloride Mass Balance (CMB) and Water Table Fluctuations (WTF) were considered to quantify groundwater recharge for the basin. Indices such as water quality index (WQI), sodium adsorption ratio (SAR), Wilcox diagram, and salinity (USSL) were used in this study to determine the quality of the resource for use as drinking water and for irrigation purposes. Due to the heterogeneity of the hydrochemical data, the statistical techniques of hierarchical cluster and factor analysis were applied to subdivide the data according to their spatial correlation. A conceptual hydrogeochemical model was developed and subsequently validated by applying combinatorial inverse and reaction pathway-based geochemical models to determine plausible mineral assemblages that control the chemical composition of the groundwater. The interactions between water and rock determine the groundwater quality in the Pra Basin. The results underline that the groundwater is of good quality and can be used for drinking water and irrigation purposes. It was demonstrated that there is a large groundwater potential to meet the entire Pra Basin’s current and future water demands. The main recharge area was identified as the northern zone, while the southern zone is the discharge area. The predominant influence of weathering of silicate minerals plays a key role in the chemical evolution of the groundwater. The work presented here provides fundamental insights into the hydrochemistry of the Pra Basin and provides data important to water managers for informed decision-making in planning and allocating water resources for various purposes. A novel inverse modelling approach was used in this study to identify different mineral compositions that determine the chemical evolution of groundwater in the Pra Basin. This modelling technique has the potential to simulate the composition of groundwater at the basin scale with large hydrochemical heterogeneity, using average water composition to represent established spatial groupings of water chemistry.
Advancing digitalization is changing society and has far-reaching effects on people and companies. Fundamental to these changes are the new technological possibilities for processing data on an ever-increasing scale and for various purposes. The availability of large and high-quality data sets, especially those based on personal data, is crucial. They are used either to improve the productivity, quality, and individuality of products and services or to develop new types of services. Today, user behavior is tracked more actively and comprehensively than ever despite increasing legal requirements for protecting personal data worldwide. That increasingly raises ethical, moral, and social questions, which have moved to the forefront of the political debate, not least due to popular cases of data misuse. Given this discourse and the legal requirements, today's data management must fulfill three conditions: Legality or legal conformity of use and ethical legitimacy. Thirdly, the use of data should add value from a business perspective. Within the framework of these conditions, this cumulative dissertation pursues four research objectives with a focus on gaining a better understanding of
(1) the challenges of implementing privacy laws,
(2) the factors that influence customers' willingness to share personal data,
(3) the role of data protection for digital entrepreneurship, and
(4) the interdisciplinary scientific significance, its development, and its interrelationships.