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Internet interventions have gained popularity and the idea is to use them to increase the availability of psychological treatment. Research suggests that internet interventions are effective for a number of psychological disorders with effect sizes comparable to those found in face-to-face treatment. However, when provided as an add-on to treatment as usual, internet interventions do not seem to provide additional benefit. Furthermore, adherence and dropout rates vary greatly between studies, limiting the generalizability of the findings. This underlines the need to further investigate differences between internet interventions, participating patients, and their usage of interventions. A stronger focus on the processes of change seems necessary to better understand the varying findings regarding outcome, adherence and dropout in internet interventions. Thus, the aim of this dissertation was to investigate change processes in internet interventions and the factors that impact treatment response. This could help to identify important variables that should be considered in research on internet interventions as well as in clinical settings that make use of internet interventions.
Study I (Chapter 5) investigated early change patterns in participants of an internet intervention targeting depression. Data from 409 participants were analyzed using Growth Mixture Modeling. Specifically a piecewise model was applied to model change from screening to registration (pretreatment) and early change (registration to week four of treatment). Three early change patterns were identified; two were characterized by improvement and one by deterioration. The patterns were predictive of treatment outcome. The results therefore indicated that early change should be closely monitored in internet interventions, as early change may be an important indicator of treatment outcome.
Study II (Chapter 6) picked up on the idea of analyzing change patterns in internet interventions and extended it by using the Muthen-Roy model to identify change-dropout patterns. A sligthly bigger sample of the dataset from Study I was analyzed (N = 483). Four change-dropout patterns emerged; high risk of dropout was associated with rapid improvement and deterioration. These findings indicate that clinicians should consider how dropout may depend on patient characteristics as well as symptom change, as dropout is associated with both deterioration and a good enough dosage of treatment.
Study III (Chapter 7) compared adherence and outcome in different participant groups and investigated the impact of adherence to treatment components on treatment outcome in an internet intervention targeting anxiety symptoms. 50 outpatient participants waiting for face- to-face treatment and 37 self-referred participants were compared regarding adherence to treatment components and outcome. In addition, outpatient participants were compared to a matched sample of outpatients, who had no access to the internet intervention during the waiting period. Adherence to treatment components was investigated as a predictor of treatment outcome. Results suggested that especially adherence may vary depending on participant group. Also using specific measures of adherence such as adherence to treatment components may be crucial to detect change mechanisms in internet interventions. Fostering adherence to treatment components in participants may increase the effectiveness of internet interventions.
Results of the three studies are discussed and general conclusions are drawn.
Implications for future research as well as their utility for clinical practice and decision- making are presented.
Background
In light of the current biodiversity crisis, DNA barcoding is developing into an essential tool to quantify state shifts in global ecosystems. Current barcoding protocols often rely on short amplicon sequences, which yield accurate identification of biological entities in a community but provide limited phylogenetic resolution across broad taxonomic scales. However, the phylogenetic structure of communities is an essential component of biodiversity. Consequently, a barcoding approach is required that unites robust taxonomic assignment power and high phylogenetic utility. A possible solution is offered by sequencing long ribosomal DNA (rDNA) amplicons on the MinION platform (Oxford Nanopore Technologies).
Findings
Using a dataset of various animal and plant species, with a focus on arthropods, we assemble a pipeline for long rDNA barcode analysis and introduce a new software (MiniBar) to demultiplex dual indexed Nanopore reads. We find excellent phylogenetic and taxonomic resolution offered by long rDNA sequences across broad taxonomic scales. We highlight the simplicity of our approach by field barcoding with a miniaturized, mobile laboratory in a remote rainforest. We also test the utility of long rDNA amplicons for analysis of community diversity through metabarcoding and find that they recover highly skewed diversity estimates.
Conclusions
Sequencing dual indexed, long rDNA amplicons on the MinION platform is a straightforward, cost-effective, portable, and universal approach for eukaryote DNA barcoding. Although bulk community analyses using long-amplicon approaches may introduce biases, the long rDNA amplicons approach signifies a powerful tool for enabling the accurate recovery of taxonomic and phylogenetic diversity across biological communities.
L’enseignement participatif
(2019)
L‘école est un lieu de socialisation des enfants et des jeunes. Les heures de cours de l‘enseignement des différentes matières sont un espace d‘expérimentation de cette socialisation. Elles marquent par leur durée dans la journée aussi bien le rôle fondamental de l‘école que l‘action et la perception à la fois des enseignant(e)s et des apprenant(e)s. Il apparaît donc d’autant plus important d’intégrer ces cours dans l’organisation d’une culture scolaire démocratique.
L’enseignement participatif, qui ne se résume pas à une participation vécue ponctuellement, comme l’écrit Charlotte Keuler dans l’article principal de ce carnet, est devenu indispensable à plusieurs égards en raison des défis auxquels nous confronte notre monde globalisé. La capacité à communiquer, les compétences interculturelles, la gestion des connaissances et d’autres « soft skills » sont les compétences clés du 21e siècle.
Finding behavioral parameterization for a 1-D water balance model by multi-criteria evaluation
(2019)
Evapotranspiration is often estimated by numerical simulation. However, to produce accurate simulations, these models usually require on-site measurements for parameterization or calibration. We have to make sure that the model realistically reproduces both, the temporal patterns of soil moisture and evapotranspiration. In this study, we combine three sources of information: (i) measurements of sap velocities; (ii) soil moisture; and (iii) expert knowledge on local runoff generation and water balance to define constraints for a “behavioral” forest stand water balance model. Aiming for a behavioral model, we adjusted soil moisture at saturation, bulk resistance parameters and the parameters of the water retention curve (WRC). We found that the shape of the WRC influences substantially the behavior of the simulation model. Here, only one model realization could be referred to as “behavioral”. All other realizations failed for a least one of our evaluation criteria: Not only transpiration and soil moisture are simulated consistently with our observations, but also total water balance and runoff generation processes. The introduction of a multi-criteria evaluation scheme for the detection of unrealistic outputs made it possible to identify a well performing parameter set. Our findings indicate that measurement of different fluxes and state variables instead of just one and expert knowledge concerning runoff generation facilitate the parameterization of a hydrological model.
Bewertungsprozesse in der Schule als Möglichkeit nutzen, um Schüler*innen bei der realistischen Einschätzung und Weiterentwicklung ihrer Lernprozesse und ihres Lernverhaltens zu unterstützen: Die partizipative Leistungsbewertung bietet verschiedene praxisnahe Ansätze zur Förderung von Lernmotivation, Selbstreflexion und demokratischem Verständnis.
Harvesting of silage maize in late autumn on waterlogged soils may result in several ecological problems such as soil compaction and may subsequently be a major threat to soil fertility in Europe. It was hypothesized that perennial energy crops might reduce the vulnerability for soil compaction through earlier harvest dates and improved soil stability. However, the performance of such crops to be grown on soil that are periodically waterlogged and implications for soil chemical and microbial properties are currently an open issue. Within the framework of a two-year pot experiment we investigated the potential of the cup plant (Silphium perfoliatum L.), Jerusalem artichoke (Helianthus tuberosus), giant knotweed (Fallopia japonicum X bohemica), tall wheatgrass (Agropyron elongatum), and reed canary grass (Phalaris arundinacea) for cultivation under periodically waterlogged soil conditions during the winter half year and implications for soil chemical and biological properties. Examined perennial energy crops coped with periodical waterlogging and showed yields 50% to 150% higher than in the control which was never faced with waterlogging. Root formation was similar in waterlogged and non-waterlogged soil layers. Soil chemical and microbial properties clearly responded to different soil moisture treatments. For example, dehydrogenase activity was two to four times higher in the periodically waterlogged treatment compared to the control. Despite waterlogging, aerobic microbial activity was significantly elevated indicating morphological and metabolic adaptation of the perennial crops to withstand waterlogged conditions. Thus, our results reveal first evidence of a site-adapted biomass production on periodical waterlogged soils through the cultivation of perennial energy crops and for intense plant microbe interactions.
A satellite-based climatology of wind-induced surface temperature anomalies for the Antarctic
(2019)
It is well-known that katabatic winds can be detected as warm signatures in the surface temperature over the slopes of the Antarctic ice sheets. For appropriate synoptic forcing and/or topographic channeling, katabatic surges occur, which result in warm signatures also over adjacent ice shelves. Moderate Resolution Imaging Spectroradiometer (MODIS) ice surface temperature (IST) data are used to detect warm signatures over the Antarctic for the winter periods 2002–2017. In addition, high-resolution (5 km) regional climate model data is used for the years of 2002 to 2016. We present a case study and a climatology of wind-induced IST anomalies for the Ross Ice Shelf and the eastern Weddell Sea. The IST anomaly distributions show maxima around 10–15K for the slopes, but values of more than 25K are also found. Katabatic surges represent a strong climatological signal with a mean warm anomaly of more than 5K on more than 120 days per winter for the Byrd Glacier and the Nimrod Glacier on the Ross Ice Shelf. The mean anomaly for the Brunt Ice Shelf is weaker, and exceeds 5K on about 70 days per winter. Model simulations of the IST are compared to the MODIS IST, and show a very good agreement. The model data show that the near-surface stability is a better measure for the response to the wind than the IST itself.
This doctoral thesis includes five studies that deal with the topics work, well-being, and family formation, as well as their interaction. The studies aim to find answers to the following questions: Do workers’ personality traits determine whether they sort into jobs with performance appraisals? Does job insecurity result in lower quality and quantity of sleep? Do public smoking bans affect subjective well-being by changing individuals’ use of leisure time? Can risk preferences help to explain non-traditional family forms? And finally, are differences in out-of-partnership birth rates between East and West Germany driven by cultural characteristics that have evolved in the two separate politico-economic systems? To answer these questions, the following chapters use basic economic subjects such as working conditions, income, and time use, but also employ a range of sociological and psychological concepts such as personality traits and satisfaction measures. Furthermore, all five studies use data from the German Socio-Economic Panel (SOEP), a representative longitudinal panel of private households in Germany, and apply state-of-the-art microeconometric methods. The findings of this doctoral thesis are important for individuals, employers, and policymakers. Workers and employers benefit from knowing the determinants of occupational sorting, as vacancies can be filled more accurately. Moreover, knowing which job-related problems lead to lower well-being and potentially higher sickness absence likely increases efficiency in the workplace. The research on smoking bans and family formation in chapters 4, 5, and 6 is particularly interesting for policymakers. The results on the effects of smoking bans on subjective well-being presented in chapter 4 suggest that the impacts of tobacco control policies could be weighed more carefully. Additionally, understanding why women are willing to take the risks associated with single motherhood can help to improve policies targeting single mothers.
Participer à l’enseignement dès le plus jeune âge – est-ce possible ? Les discussions et les processus de négociation et de décision ne nécessitent-ils pas une certaine maturité dont les enfants de trois ans ne disposent pas encore ? L’équipe mateneen s’est fait une idée du travail avec des enfants préscolaires et a constaté : que c’était tout à fait possible !
Le feedback à l’école ? Il s’agit souvent d’un simple retour d’informations des enseignant(e)s sur le travail des élèves en classe. Cependant, une culture du feedback solide en classe offre de nombreuses possibilités pour pratiquer l’action démocratique et améliorer la qualité de l’enseignement, tout en faisant participer enseignant(e)s et apprenant(e)s.
Considérer les processus d’évaluation à l’école comme une possibilité pour soutenir les élèves dans l’évaluation réaliste et le développement de leurs processus et leur comportement d’apprentissage : l’évaluation participative des performances offre différentes possibilités pratiques pour favoriser la motivation d’apprendre, l’autoréflexion et la compréhension démocratique.
La participation des élèves ne devrait pas se limiter à l’implication dans l’organisation et l’évaluation des cours. Une culture de tâches participative offre de nombreuses possibilités pour pratiquer et analyser la participation démocratique à l’aide d’actions réelles ou simulées dans l’apprentissage technique.
Many combinatorial optimization problems on finite graphs can be formulated as conic convex programs, e.g. the stable set problem, the maximum clique problem or the maximum cut problem. Especially NP-hard problems can be written as copositive programs. In this case the complexity is moved entirely into the copositivity constraint.
Copositive programming is a quite new topic in optimization. It deals with optimization over the so-called copositive cone, a superset of the positive semidefinite cone, where the quadratic form x^T Ax has to be nonnegative for only the nonnegative vectors x. Its dual cone is the cone of completely positive matrices, which includes all matrices that can be decomposed as a sum of nonnegative symmetric vector-vector-products.
The related optimization problems are linear programs with matrix variables and cone constraints.
However, some optimization problems can be formulated as combinatorial problems on infinite graphs. For example, the kissing number problem can be formulated as a stable set problem on a circle.
In this thesis we will discuss how the theory of copositive optimization can be lifted up to infinite dimension. For some special cases we will give applications in combinatorial optimization.
An Grundschulen bietet der Klassenrat eine Möglichkeit für Schüler*innen, erste Schritte demokratischen Umgangs zu erlernen oder auch zu vertiefen. Hier lernen sie in einem geschützten Raum sich zu verschiedensten Themen zu äußern, Konflikte lösungsorientiert zu verarbeiten und Verantwortung zu übernehmen. Die hier vorgestellten Materialien sollen bei der Einführung und Durchführung des Klassenrats helfen.
Background: Increasing exposure to engineered inorganic nanoparticles takes actually place in both terrestric and aquatic ecosystems worldwide. Although we already know harmful effects of AgNP on the soil bacterial community, information about the impact of the factors functionalization, concentration, exposure time, and soil texture on the AgNP effect expression are still rare. Hence, in this study, three soils of different grain size were exposed for up to 90 days to bare and functionalized AgNP in concentrations ranging from 0.01 to 1.00 mg/kg soil dry weight. Effects on soil microbial community were quantified by various biological parameters, including 16S rRNA gene, photometric, and fluorescence analyses.
Results: Multivariate data analysis revealed significant effects of AgNP exposure for all factors and factor combinations investigated. Analysis of individual factors (silver species, concentration, exposure time, soil texture) in the unifactorial ANOVA explained the largest part of the variance compared to the error variance. In depth analysis of factor combinations revealed even better explanation of variance. For the biological parameters assessed in this study, the matching of soil texture and silver species, and the matching of soil texture and exposure time were the two most relevant factor combinations. The factor AgNP concentration contributed to a lower extent to the effect expression compared to silver species, exposure time and physico–chemical composition of soil.
Conclusions: The factors functionalization, concentration, exposure time, and soil texture significantly impacted the effect expression of AgNP on the soil microbial community. Especially long-term exposure scenarios are strongly needed for the reliable environmental impact assessment of AgNP exposure in various soil types.
When do anorexic patients perceive their body as too fat? Aggravating and ameliorating factors
(2019)
Objective
Our study investigated body image representations in female patients with anorexia nervosa
and healthy controls using a size estimation with pictures of their own body. We also
explored a method to reduce body image distortions through right hemispheric activation.
Method
Pictures of participants’ own bodies were shown on the left or right visual fields for 130 ms
after presentation of neutral, positive, or negative word primes, which could be self-relevant
or not, with the task of classifying the picture as “thinner than”, “equal to”, or “fatter than”
one’s own body. Subsequently, activation of the left- or right hemispheric through right- or
left-hand muscle contractions for 3 min., respectively. Finally, participants completed the
size estimation task again.
Results
The distorted “fatter than” body image was found only in patients and only when a picture of
their own body appeared on the right visual field (left hemisphere) and was preceded by
negative self-relevant words. This distorted perception of the patients’ body image was
reduced after left-hand muscle contractions (right hemispheric activation).
Discussion
To reduce body image distortions it is advisable to find methods that help anorexia nervosa
patients to increase their self-esteem. The body image distortions were ameliorated after
right hemispheric activation. A related method to prevent distorted body-image representations
in these patients may be Eye Movement Desensitization and Reprocessing (EMDR)
therapy.
Because EU water quality policy can result in infrastructure creation or adaptation at the local level across member states, compliance cases are worth examining critically from a sustainable spatial planning perspective. In this study, the 2000 EU Water Framework Directive’s (WFD) reach to local implementation efforts in average towns and cities is shown through the case study of nonconforming household wastewater infrastructure in the German state of Rhineland Palatinate. Seeing wastewater as a socio-technical infrastructure, we ask how the WFD implementation can be understood in the context of local infrastructure development, sustainability, and spatial planning concepts. In particular, this study examines what compliance meant for the centralization or decentralization of local wastewater infrastructure systems—and the sustainability implications for cities
from those choices.
Die Implementierung eines Klassenrats ist mit der Hoffnung verbunden, die demokratischen Kompetenzen von Schüler*innen zu stärken. Welche Kompetenzen die Teilnehmer*innen mithilfe dieser demokratiepädagogischen Methode tatsächlich erwerben und wie sich der Klassenrat auf die Klassengemeinschaft auswirkt, hat eine empirische Studie1 am Lycée Nic Biever in Dudelange untersucht.
In this thesis, we consider the solution of high-dimensional optimization problems with an underlying low-rank tensor structure. Due to the exponentially increasing computational complexity in the number of dimensions—the so-called curse of dimensionality—they present a considerable computational challenge and become infeasible even for moderate problem sizes.
Multilinear algebra and tensor numerical methods have a wide range of applications in the fields of data science and scientific computing. Due to the typically large problem sizes in practical settings, efficient methods, which exploit low-rank structures, are essential. In this thesis, we consider an application each in both of these fields.
Tensor completion, or imputation of unknown values in partially known multiway data is an important problem, which appears in statistics, mathematical imaging science and data science. Under the assumption of redundancy in the underlying data, this is a well-defined problem and methods of mathematical optimization can be applied to it.
Due to the fact that tensors of fixed rank form a Riemannian submanifold of the ambient high-dimensional tensor space, Riemannian optimization is a natural framework for these problems, which is both mathematically rigorous and computationally efficient.
We present a novel Riemannian trust-region scheme, which compares favourably with the state of the art on selected application cases and outperforms known methods on some test problems.
Optimization problems governed by partial differential equations form an area of scientific computing which has applications in a variety of areas, ranging from physics to financial mathematics. Due to the inherent high dimensionality of optimization problems arising from discretized differential equations, these problems present computational challenges, especially in the case of three or more dimensions. An even more challenging class of optimization problems has operators of integral instead of differential type in the constraint. These operators are nonlocal, and therefore lead to large, dense discrete systems of equations. We present a novel solution method, based on separation of spatial dimensions and provably low-rank approximation of the nonlocal operator. Our
approach allows the solution of multidimensional problems with a complexity which is only slightly larger than linear in the univariate grid size; this improves the state of the art for a particular test problem problem by at least two orders of magnitude.
Petits pays ayant d’importants besoins de main-d’œuvre, le Luxembourg et la Suisse attirent tous deux un grand nombre de travailleurs frontaliers. C’est dans une perspective comparative que les 19 auteurs impliqués dans ce Cahier Thématique analysent la situation des travailleurs frontaliers dans les principaux pôles d’emploi transfrontaliers (Luxembourg, Bâle, Genève), mais également au Tessin. En tenant compte des éléments contextuels et méthodologiques, géographes, économistes, sociologues et politologues se focalisent sur les questions d’emploi, le quotidien transfrontalier et les perceptions des frontaliers par la société. Cette approche collective et pluridisciplinaire est résumée par les éditeurs en identifiant des enjeux communs pour le Luxembourg et la Suisse.
Die Praxishefte Demokratische Schulkultur erscheinen halbjährlich und bieten Schulleitungen und Schulpersonal theoretische Grundlagen und praxisorientierte Anleitungen zur demokratiepädagogischen Schulentwicklung. Jedes Themenheft ist jeweils einer demokratiepädagogischen Bauform oder strategischen Frage der Schulentwicklung gewidmet. Die Praxishefte werden allen Luxemburger Schulen als Printausgabe zur Verfügung gestellt und online mit zusätzlichen Materialien und in französischer Fassung vorgehalten.
Demokratie lebt von der Beteiligung engagierter Bürger*innen. Hierzu ist es notwendig, Kinder und Jugendliche frühzeitig an demokratische Handlungsweisen heranzuführen. Der demokratiepädagogische Klassenrat bietet vielfältige Chancen, Schüler*innen Partizipationserfahrungen zu eröffnen und ihre demokratischen Kompetenzen zu stärken.
C’est la participation des citoyen(ne)s engagé(e)s qui fait vivre la démocratie. À cette fin, il est nécessaire de familiariser le plus tôt possible les enfants et les adolescents aux méthodes démocratiques. Le conseil de coopération est un outil d’éducation à la démocratie qui offre aux élèves de nombreuses possibilités pour expérimenter la participation et renforcer leurs compétences démocratiques.
Den Klassenrat einführen
(2019)
Bevor eine Einführung des Klassenrats in einer Schulklasse erfolgen kann, sind organisatorische, inhaltliche und methodische Vorbereitungen erforderlich. Der Beitrag gibt Hinweise zur Einführung des Klassenrats und bietet konkrete Methoden, die eine erfolgreiche Implementierung in einer Schulklasse unterstützen.
La mise en œuvre d’un conseil de coopération est liée à l’espoir de renforcer les compétences démocratiques des élèves. Une étude empirique1 réalisée au Lycée Nic Biever de Dudelange a analysé les compétences réellement acquises par les participant(e)s grâce à cette méthode d’éducation à la démocratie ainsi que l’impact du conseil de coopération sur la classe.
Auch in Sekundarschulen bietet der Klassenrat den Schüler*innen Raum, um ihre Anliegen zu artikulieren und in einem demokratischen Prozess Verbesserungspotenziale für die Klasse und Schule auszuloten. Die vorliegenden Materialien helfen dabei, die Sitzungen eigenverantwortlich vorzubereiten und durchzuführen.
Die Großregion gilt als eine der wichtigsten Regionen der grenzüberschreitenden Zusammenarbeit in der Europäischen Union. Nach Beginn der Zusammenarbeit in den siebziger Jahren entwickelte sich die Koope-ration im Bereich der Raumplanung zu einer wichtigen Säule. Dennoch sind konkrete Nachweise, die die hohe Bedeutung einer grenzüberschreitenden Raumplanung bestätigen eher selten zu finden. Aufgegriffen wird diese Thematik meist nur in Bezug auf den gesetzlichen und institutionellen Rahmen.
Das vorliegende Strategiepapier setzt voraus, dass die grenzüberschreitende Raumplanung über die Ge-setze, Pläne und Konzepte hinaus auch aus Planungspraktiken resultiert, die darauf abzielen gesellschaftli-che Bedürfnisse an den Raum langfristig zu berücksichtigen.
Nach einer kurzen Präsentation der wichtigsten Meilensteine der Zusammenarbeit im Bereich der grenz-überschreitenden Raumplanung in der Großregion, stellt dieses Strategiepapier die Ergebnisse eines expe-rimentellen Workshops (Planspiel) vor, der im Jahr 2017 stattfand und bei dem sowohl Forscher als auch Planungspraktiker involviert waren. Abschließend stellt das Dokument eine Reihe von Empfehlungen vor, die auf der Analyse des Forschungsmaterials basieren.
Dans les écoles secondaires, le conseil de coopération offre aussi aux élèves un espace pour exprimer leurs demandes et explorer, dans un processus démocratique, les potentiels d’amélioration pour la classe et l’école. Les supports ci-dessous vous aideront à préparer et à mener les réunions de manière autonome.
Faut-il interdire les emballages en plastique ? Quels arguments s’opposent au droit de vote à partir de 14 ans ? Quelles sont les conséquences du Brexit sur l’Europe ? – Ce type de questions a toute sa place en conseil de coopération, car leur discussion offre des possibilités d’apprentissage des processus démocratiques.
Sollten Plastikverpackungen verboten werden? Was spricht gegen eine Wahlberechtigung ab 14 Jahren? Wie sollte die EU mit möglichen Auswirkungen des Brexits umgehen? – Auch solche Fragen haben im Klassenrat ihre Berechtigung, denn ihre Diskussion bietet besondere Chancen für demokratische Lernprozesse.
Les carnets paraissent biannuellement et offrent aux dirigeant(e)s des écoles ainsi qu’au personnel des fondements théoriques et du matériel pratique pour la mise en œuvre d’un développement scolaire démocratique. Chaque publication traite d’une méthode de l’éducation à la démocratie ou d’une question stratégique du développement scolaire. Les carnets en langue allemande sont mis à disposition des écoles luxembourgeoises en version imprimée. Tous le matériel ainsi que la version en langue française sont disponibles en ligne.
Dans les écoles fondamentales, le conseil de coopération offre aux élèves la possibilité d’apprendre et d’approfondir les premières étapes de la gestion démocratique. Dans un espace protégé, ils / elles apprennent à s’exprimer sur les thèmes les plus divers, à résoudre les conflits en se concentrant sur les solutions et à prendre des responsabilités. Les supports présentés ici ont pour objectif de vous aider à mettre en place et à mener à bien le conseil de coopération.
A huge number of clinical studies and meta-analyses have shown that psychotherapy is effective on average. However, not every patient profits from psychotherapy and some patients even deteriorate in treatment. Due to this result and the restricted generalization of clinical studies to clinical practice, a more patient-focused research strategy has emerged. The question whether a particular treatment works for an individual case is the focus of this paradigm. The use of repeated assessments and the feedback of this information to therapists is a major ingredient of patient-focused research. Improving patient outcomes and reducing dropout rates by the use of psychometric feedback seems to be a promising path. Therapists seem to differ in the degree to which they make use of and profit from such feedback systems. This dissertation aims to better understand therapist differences in the context of patient-focused research and the impact of therapists on psychotherapy. Three different studies are included, which focus on different aspects within the field:
Study I (Chapter 5) investigated how therapists use psychometric feedback in their work with patients and how much therapists differ in their usage. Data from 72 therapists treating 648 patients were analyzed. It could be shown that therapists used the psychometric feedback for most of their patients. Substantial variance in the use of feedback (between 27% and 52%) was attributable to therapists. Therapists were more likely to use feedback when they reported being satisfied with the graphical information they received. The results therefore indicated that not only patient characteristics or treatment progress affected the use of feedback.
Study II (Chapter 6) picked up on the idea of analyzing systematic differences in therapists and applied it to the criterion of premature treatment termination (dropout). To answer the question whether therapist effects occur in terms of patients’ dropout rates, data from 707 patients treated by 66 therapists were investigated. It was shown that approximately six percent of variance in dropout rates could be attributed to therapists, even when initial impairment was controlled for. Other predictors of dropout were initial impairment, sex, education, personality styles, and treatment expectations.
Study III (Chapter 7) extends the dissertation by investigating the impact of a transfer from one therapist to another within ongoing treatments. Data from 124 patients who agreed to and experienced a transfer during their treatment were analyzed. A significant drop in patient-rated as well as therapist-rated alliance levels could be observed after a transfer. On average, there seemed to be no difficulties establishing a good therapeutic alliance with the new therapist, although differences between patients were observed. There was no increase in symptom severity due to therapy transfer. Various predictors of alliance and symptom development after transfer were investigated. Impacts on clinical practice were discussed.
Results of the three studies are discussed and general conclusions are drawn. Implications for future research as well as their utility for clinical practice and decision-making are presented.
Die Partizipationskompetenz von Schülerinnen und Schülern sollte nicht nur durch eine Beteiligung an der formalen Gestaltung und Bewertung des Unterrichts gefördert werden. Vielmehr bietet eine entsprechende Aufgabenkultur vielfältige Möglichkeiten, demokratische Partizipation durch simulatives oder reales Handeln im fachlichen Lernen zu üben und zu reflektieren.
In this thesis, we aim to study the sampling allocation problem of survey statistics under uncertainty. We know that the stratum specific variances are generally not known precisely and we have no information about the distribution of uncertainty. The cost of interviewing each person in a stratum is also a highly uncertain parameter as sometimes people are unavailable for the interview. We propose robust allocations to deal with the uncertainty in both stratum specific variances and costs. However, in real life situations, we can face such cases when only one of the variances or costs is uncertain. So we propose three different robust formulations representing these different cases. To the best of our knowledge robust allocation in the sampling allocation problem has not been considered so far in any research.
The first robust formulation for linear problems was proposed by Soyster (1973). Bertsimas and Sim (2004) proposed a less conservative robust formulation for linear problems. We study these formulations and extend them for the nonlinear sampling allocation problem. It is very unlikely to happen that all of the stratum specific variances and costs are uncertain. So the robust formulations are in such a way that we can select how many strata are uncertain which we refer to as the level of uncertainty. We prove that an upper bound on the probability of violation of the nonlinear constraints can be calculated before solving the robust optimization problem. We consider various kinds of datasets and compute robust allocations. We perform multiple experiments to check the quality of the robust allocations and compare them with the existing allocation techniques.
Cet article analyse les pratiques quotidiennes des habitants de Sarre, de Lorraine, du Luxembourg, de Rhénanie-Palatinat et de Wallonie effectuées dans les régions voisines. L’hypothèse est l’existence d’une réalité de vie transfrontalière dans la Grande Région à partir des pratiques transfrontalières de ses habitants. Dans une telle perspective socio-constructiviste, on ne demande pas ce qu'est la Grande Région SaarLorLux, mais comment elle est constituée ou comment elle se manifeste dans la vie quotidienne de ses habitants. Pour donner des éléments de réponse, seront analysées les pratiques transfrontalières les plus courantes, notamment le fait de faire des achats et du shopping, se détendre dans la nature/faire du tourisme, fréquenter des manifestations culturelles et rendre visite à des amis et à la famille. Les considérations se basent sur trois études empiriques récentes dans l’espace d'analyse, qui sont mises en rapport et contextualisées socio-culturellement et socio-économiquement dans le but de relever l'organisation spatiale, les motivations ainsi que d'autres facteurs contextuels des pratiques transfrontalières dans la Grande Région SaarLorLux. Dans cette approche, les flux de mobilité et les préférences spatiales sont reconstruits à partir des pratiques quotidiennes qui donnent un aperçu des réalités de vie transfrontalière dans la Grande Région SaarLorLux.
In dem Beitrag wird ein praxissoziologischer Ansatz für die Beschreibung und Analyse der grenzüberschreitenden Zusammenarbeit vorgestellt. Dafür wird zunächst die Entwicklung der Kooperationsforschung, ihre charakteristischen Orientierungen sowie die Grundzüge praxistheoretischen Denkens skizziert. Darauf aufbauend wird die heuristische Denkfigur der grenzüberschreitenden Praxisformation erarbeitet, die mit Prämissen herkömmlicher Kooperationsforschung bricht. Sie wird am Beispiel von vier Herausforderungen der grenzüberschreitenden Zusammenarbeit weiter ausdifferenziert, um schließlich zu einer alternativen Perspektivierung der grenzüberschreitenden Zusammenarbeit zu gelangen. Es folgt ein Ausblick, der auf die forschungspraktischen Besonderheiten des vorgestellten Ansatzes eingeht mit Blick auf eine künftige praxissoziologische und multidisziplinär anschlussfähige Kooperationsforschung.
Fachunterricht ist der zentrale Erfahrungsraum im Sozialisationsumfeld Schule. Er prägt schon allein aufgrund seines hohen zeitlichen Anteils im Tagesverlauf und der grundlegenden Funktion von Schule Handeln und Wahrnehmung von Lehrpersonen und Lernenden. Umso wichtiger ist es, ihn in die Gestaltung einer demokratischen Schulkultur einzubeziehen.
Partizipativer Unterricht, der nicht nur aus punktuell erlebter Teilnahme besteht, ist — wie Charlotte Keuler es im Leitartikel des vorliegenden Heftes formuliert — durch die Herausforderungen, vor die uns unsere globalisierte Welt stellt, in vielerlei Hinsicht unabdingbar geworden. Kommunikationsfähigkeit, interkulturelle Kompetenz, Wissensmanagement und andere oft zitierte „soft skills“ sind Schlüsselkompetenzen des 21. Jahrhunderts.
Partizipation im Unterricht von klein auf – geht das? Braucht man für Diskussionen, Aushandlungs-und Entscheidungsprozesse nicht eine bestimmte Reife, über die Dreijährige noch gar nicht verfügen? Das mateneen-Team hat sich auf Limpertsberg ein Bild von der Arbeit mit Vorschulkindern gemacht und festgestellt: das geht sehr wohl!
Feedback in der Schule? Das bedeutet häufig eine kurze Rückmeldung der Lehrer*innen an die Schüler*innen zu deren Mitarbeit. Dabei bietet eine etablierte Feedbackkultur im Unterricht breite Möglichkeiten, demokratisches Handeln zu üben und die Unterrichtsqualität zu verbessern, und muss keineswegs nur einseitig ausfallen.
Die Praxishefte Demokratische Schulkultur erscheinen halbjährlich und bieten Schulleitungen und Schulpersonal theoretische Grundlagen und praxisorientierte Anleitungen zur demokratiepädagogischen Schulentwicklung. Jedes Themenheft ist jeweils einer demokratiepädagogischen Bauform oder strategischen Frage der Schulentwicklung gewidmet. Die Praxishefte werden allen Luxemburger Schulen als Printausgabe zur Verfügung gestellt und online mit zusätzlichen Materialien und in französischer Fassung vorgehalten.
Forschungsprozessspezifische Kompetenzmatrix für die Einführung des Forschungsdatenmanagements (FDM)
(2019)
Die forschungsprozessspezifische Kompetenzmatrix stellt einen Baustein im Rahmen des durch das BMBF geförderten Forschungsprojektes „Prozessorientierte Entwicklung von Managementinstrumenten für Forschungsdaten im Lebenszyklus“ (PODMAN) dar. Im Rahmen des PODMAN-Projektes soll ein Referenzmodell und ein zugehöriges prozessorientiertes Benchmarking-Verfahren zur Implementierung des Forschungsdatenmanagements an Hochschulen und außeruniversitären Forschungseinrichtungen entwickelt werden. Darüber soll den Hochschulen und außeruniversitären Forschungseinrichtungen ein Orientierungsrahmen bereitgestellt werden, den sie flexibel zur Umsetzung eigener Datenmanagementstrategien nutzen können. In diesem Zusammenhang sollen Instrumente entwickelt werden, welche eine erfolgreiche Organisation der Zusammenarbeit und Kommunikation sowie der Qualifizierung aller am Forschungsdatenmanagementprozess beteiligten Akteure erlauben. Die forschungsprozessspezifische Kompetenzmatrix hat als eines dieser Instrumente zwei Funktionen: Erstens definiert sie die zur Implementierung eines umfassenden institutionellen FDM-Konzeptes notwendigen Aufgaben und zweitens die damit verbundenen Kompetenzen der ausführenden Akteure.
Ziel der hier bereitgestellten Anforderungskataloge ist es, einen Überblick über die Anforderungen zu geben, welche an FDM-Services in den Geisteswissenschaften und in der Psychologie gestellt werden. Dies soll Hochschulen und außeruniversitären Forschungseinrichtungen die Möglichkeit geben, ihre eigenen Servicekataloge um FDM-Services zu erweitern, welche auf die spezifischen Bedarfe der Forschenden in diesen Disziplinen abgestimmt sind. Zudem sollen diese Anforderungskataloge als Vorlage für die Entwicklung weiterer Anforderungskataloge dienen, welche die fachspezifischen FDM-Services in anderen Fachdisziplinen spezifizieren.
This thesis discusses revue as a significantly inter-cultural genre in the history of global theatre. During the ‘modernisation’ period in Europe, America and Japan, most major urban cities experienced a boom in revue venues and performances. Few studies about revue have yet been done in theatre studies or in urban cultural studies. My thesis will attempt to reevaluate and redefine revue as a highly intercultural theatre genre by using the concept of liminality. In other words, the aim is to examine revue as a genre built on ‘modern composition of betweenness’, bridging seemingly opposing elements, such as the foreign and the domestic, the classic and the innovative, the traditional and the modern, the professional and the amateur, high and low culture, and the feminine and the masculine. The goal is to regard revue as a liminal genre constructed amidst the negotiations between these binaries, existing in a state of constant flux.
The purpose of this approach is to capture revue as a transitory phenomena in five dimensions: conceptual, spatial, temporal, categorical and physical. Over the course of six chapters, this
inter-disciplinary discussion will reveal the reasons why and the ways by which revue came to establish its prominent position in the Japanese theatre industry. The whole structure is also an attempt to provide plausible ways to apply sociological considerations to theatre studies.
Les carnets paraissent deux fois par an et offrent aux dirigeant(e)s des écoles ainsi qu’au personnel des fondements théoriques et du matériel pratique pour la mise en oeuvre d’un développement scolaire démocratique. Chaque publication traite d’une méthode de l’éducation à la démocratie ou d’une question stratégique du développement scolaire. Les carnets en langue allemande sont mis à la disposition des écoles luxembourgeoises en version imprimée. Tout le matériel ainsi que la version en langue française sont disponibles en ligne.
Competitive analysis is a well known method for analyzing online algorithms.
Two online optimization problems, the scheduling problems and the list accessing problems, are considered in the thesis of Yida Zhu in the respect of this method.
For both problems, several existing online and offline algorithms are studied. Their performances are compared with the performances of corresponding offline optimal algorithms.
In particular, the list accessing algorithm BIT is carefully reviewed.
The classical proof of its worst case performance get simplified by adapting the knowledge about the optimal offline algorithm.
With regard to average case analysis, a new closed formula is developed to determine the performance of BIT on specific class of instances.
All algorithm considered in this thesis are also implemented in Julia.
Their empirical performances are studied and compared with each other directly.
Thema dieser Dissertation ist das deutsche Selbstbildnis im 17. Jahrhundert. Ziel der Arbeit war es, das deutsche Selbstbildnis als eigene Gattung zu etablieren. Hierzu wurden die Selbstbildnisse deutscher Maler des 17. Jahrhunderts ausgewählt, gilt doch diese Zeit noch immer als ‚totes Jahrhundert‘. Grundlage der Untersuchung war eine Sammlung von 148 Objekten, die einer grundlegenden Analyse unterzogen wurden. Das früheste Selbstbildnis in dieser Sammlung stammt von 1600, das späteste wurde um 1700 angefertigt. Künstler aus dem gesamten Alten Reich, ob aus Schlesien und Böhmen, Nord-oder Süddeutschland oder aus den österreichischen wie schweizerischen Landen sind hier vertreten. Die Selbstbildnisse stammen von Malern in der gesamten breite ihrer Karriere. So sind gleichermaßen Selbstbildnisse von Gesellen wie Meistern, von Hofmalern bis hin zu Freimeistern vertreten. Besonders wichtig war es, nicht nur Selbstbildnisse im Gemälde oder Kupferstich in die Untersuchung aufzunehmen, sondern auch Stammbucheinträge.
Die ausführliche Betrachtung und Gegenüberstellung der deutschen Selbstbildnisse mit denen ihrer europäischen Kollegen hat gezeigt, dass auch deutsche Maler den gängigen Darstellungstypen wie etwa dem virtuoso folgten. Aber die deutschen Maler imitierten nicht nur, sondern experimentierten und gingen mit ihren Vorbildern spielerisch um. Daneben folgten sie natürlich auch den Trends der Selbstinszenierung. Sie drückten in ihren Selbstbildnissen ihren Wunsch nach sozialer und gesellschaftlicher Emanzipation des gesamten Berufsstandes aus. So war das deutsche Selbstbildnis eigenständiger Ausdruck des Aufbruches deutscher Künstler in eine neue Zeit.
This dissertation investigates corporate acquisition decisions that represent important corporate development activities for family and non-family firms. The main research objective of this dissertation is to generate insights into the subjective decision-making behavior of corporate decision-makers from family and non-family firms and their weighting of M&A decision-criteria during the early pre-acquisition target screening and selection process. The main methodology chosen for the investigation of M&A decision-making preferences and the weighting of M&A decision criteria is a choice-based conjoint analysis. The overall sample of this dissertation consists of 304 decision-makers from 264 private and public family and non-family firms from mainly Germany and the DACH-region. In the first empirical part of the dissertation, the relative importance of strategic, organizational and financial M&A decision-criteria for corporate acquirers in acquisition target screening is investigated. In addition, the author uses a cluster analysis to explore whether distinct decision-making patterns exist in acquisition target screening. In the second empirical part, the dissertation explores whether there are differences in investment preferences in acquisition target screening between family and non-family firms and within the group of family firms. With regards to the heterogeneity of family firms, the dissertation generated insights into how family-firm specific characteristics like family management, the generational stage of the firm and non-economic goals such as transgenerational control intention influences the weighting of different M&A decision criteria in acquisition target screening. The dissertation contributes to strategic management research, in specific to M&A literature, and to family business research. The results of this dissertation generate insights into the weighting of M&A decision-making criteria and facilitate a better understanding of corporate M&A decisions in family and non-family firms. The findings show that decision-making preferences (hence the weighting of M&A decision criteria) are influenced by characteristics of the individual decision-maker, the firm and the environment in which the firm operates.
Understanding the mechanisms that shape access to the fisheries ecosystem service in Tsokomey, Accra
(2019)
Questions of access to ecosystem services remain largely unaddressed. Yet, in the coming decades, addressing access to services and securing them for livelihoods and well-being of people will likely gain importance, especially to guide according policies at the local scale. Through a qualitative approach, this paper addresses the mechanisms that shape access to the fisheries eco- system service in Accra, Ghana. The analysis uses a framework that focuses on access to land, tools and technology, knowledge and information, capital and credit, as well as labor. This research reveals how access is organized across the different categories of this framework and how people’s well-being is shaped. Moreover, it helps to further our understanding of what regulates the access to ecosystem services and how to address future shocks and capacity in terms of production of ecosystem services.
In der kleinen ostfriesischen Kirchengemeinde W. hat sich im Jahr 1969 ein plötzlicher Todesfall ereignet. Fremdverschulden wird ausgeschlossen. Jemand, der die Hintergründe des Todesfalls aufklären will, stößt allenthalben auf – bisweilen gar aggressives – Schweigen. Eine Geschichte über individuelle und kollektive Schuld, lutherische Kirchenmusik und den Wert, den wir der Kultur und der Tradition beimessen.
Ausgezeichnet mit dem Borsla-Preis 2019.
In order to discuss potential sustainability issues of expanding silage maize cultivation in Rhineland-Palatinate, spatially explicit monitoring is necessary. Publicly available statistical records are often not a sufficient basis for extensive research, especially on soil health, where risk factors like erosion and compaction depend on variables that are specific to every site, and hard to generalize for larger administrative aggregates. The focus of this study is to apply established classification algorithms to estimate maize abundance for each independent pixel, while at the same time accounting for their spatial relationship. Therefore, two ways to incorporate spatial autocorrelation of neighboring pixels are combined with three different classification models. The performance of each of these modeling approaches is analyzed and discussed. Finally, one prediction approach is applied to the imagery, and the overall predicted acreage is compared to publicly available data. We were able to show that Support Vector Machine (SVM) classification and Random Forests (RF) were able to distinguish maize pixels reliably, with kappa values well above 0.9 in most cases. The Generalized Linear Model (GLM) performed substantially worse. Furthermore, Regression Kriging (RK) as an approach to integrate spatial autocorrelation into the prediction model is not suitable in use cases with millions of sparsely clustered training pixels. Gaussian Blur is able to improve predictions slightly in these cases, but it is possible that this is only because it smoothes out impurities of the reference data. The overall prediction with RF classification combined with Gaussian Blur performed well, with out of bag error rates of 0.5% in 2009 and 1.3% in 2016. Despite the low error rates, there is a discrepancy between the predicted acreage and the official records, which is 20% in 2009 and 27% in 2016.
For grape canopy pixels captured by an unmanned aerial vehicle (UAV) tilt-mounted RedEdge-M multispectral sensor in a sloped vineyard, an in situ Walthall model can be established with purely image-based methods. This was derived from RedEdge-M directional reflectance and a vineyard 3D surface model generated from the same imagery. The model was used to correct the angular effects in the reflectance images to form normalized difference vegetation index (NDVI)orthomosaics of different view angles. The results showed that the effect could be corrected to a certain scope, but not completely. There are three drawbacks that might restrict a successful angular model construction and correction: (1) the observable micro shadow variation on the canopy enabled by the high resolution; (2) the complexity of vine canopies that causes an inconsistency between reflectance and canopy geometry, including effects such as micro shadows and near-infrared (NIR) additive effects; and (3) the resolution limit of a 3D model to represent the accurate real-world optical geometry. The conclusion is that grape canopies might be too inhomogeneous for the tested method to perform the angular correction in high quality.
The forward testing effect refers to the finding that retrieval practice of previously studied information enhances learning and retention of subsequently studied other information. While most of the previous research on the forward testing effect examined group differences, the present study took an individual differences approach to investigate this effect. Experiment 1 examined whether the forward effect has test-retest reliability between two experimental sessions. Experiment 2 investigated whether the effect is related to participants’ working memory capacity. In both experiments (and each session of Experiment 1), participants studied three lists of items in anticipation of a final cumulative recall test. In the testing condition, participants were tested immediately on lists 1 and 2, whereas in the restudy condition, they restudied lists 1 and 2. In both conditions, participants were tested immediately on list 3. On the group level, the results of both experiments demonstrated a forward testing effect, with interim testing of lists 1 and 2 enhancing immediate recall of list 3. On the individual level, the results of Experiment 1 showed that the forward effect on list 3 recall has moderate test-retest reliability between two experimental sessions. In addition, the results of Experiment 2 showed that the forward effect on list 3 recall does not depend on participants’ working memory capacity. These findings suggest that the forward testing effect is reliable at the individual level and affects learners at a wide range of working memory capacities alike. The theoretical and practical implications of the findings are discussed.
Der Photograph Willi Huttig
(2019)
Auf der Grundlage einer Fragebogenstudie wurden unterschiedliche Elemente eines förderlichen Umgangs mit Gesundheitsinformationen betrachtet und ihre Zusammenhänge mit personspezifischen Merkmalen analysiert. Als zentrale Aspekte der Informationsprozesse wurden die drei Elemente Gesundheitsinformationskompetenz, Gesundheitsinteresse und gesundheitsspezifische Informationsgewohnheiten konzeptuell voneinander getrennt. Auf der Basis des bisherigen Forschungsstands wurde zunächst ein theoretisches Modell des Umgangs mit Gesundheitsinformationen entwickelt, das die Bedeutung der Kompetenz und des Interesses für gesundheitsbezogene Informationsgewohnheiten hervorhebt, individuelle Ausprägungen dieser drei Elemente mit soziodemografischen Faktoren, Persönlichkeitseigenschaften, Überzeugungen und dem Gesundheitszustand in Beziehung setzt sowie Verbindungen zu gesundheitsrelevanten Verhaltensweisen beschreibt. Dieses Modell wurde anschließend an einer Stichprobe von 352 Berufsschülerinnen und -schülern aus drei Berufsbereichen (Wirtschaft/Verwaltung, Technik und Gesundheit) empirisch überprüft. Über multiple Regressionsanalysen wurden bedeutsame Prädiktoren für die drei Hauptelemente Kompetenz, Interesse und Informationsgewohnheiten identifiziert, über logistische Regressionen und Korrelationen ihre Zusammenhänge mit dem Gesundheitsverhalten überprüft. Darüber hinaus wurden lineare Strukturgleichungsmodelle zur Vorhersage des Informationsverhaltens entwickelt. Die Ergebnisse bestätigen die konzeptionelle Trennung der drei Faktoren, die jeweils mit unterschiedlichen Prädiktoren verbunden waren. Auf der Basis der Befunde werden Ansatzpunkte für die weitere Forschung und die Förderung eines kompetenten Umgangs mit Gesundheitsinformationen diskutiert.
We consider a linear regression model for which we assume that some of the observed variables are irrelevant for the prediction. Including the wrong variables in the statistical model can either lead to the problem of having too little information to properly estimate the statistic of interest, or having too much information and consequently describing fictitious connections. This thesis considers discrete optimization to conduct a variable selection. In light of this, the subset selection regression method is analyzed. The approach gained a lot of interest in recent years due to its promising predictive performance. A major challenge associated with the subset selection regression is the computational difficulty. In this thesis, we propose several improvements for the efficiency of the method. Novel bounds on the coefficients of the subset selection regression are developed, which help to tighten the relaxation of the associated mixed-integer program, which relies on a Big-M formulation. Moreover, a novel mixed-integer linear formulation for the subset selection regression based on a bilevel optimization reformulation is proposed. Finally, it is shown that the perspective formulation of the subset selection regression is equivalent to a state-of-the-art binary formulation. We use this insight to develop novel bounds for the subset selection regression problem, which show to be highly effective in combination with the proposed linear formulation.
In the second part of this thesis, we examine the statistical conception of the subset selection regression and conclude that it is misaligned with its intention. The subset selection regression uses the training error to decide on which variables to select. The approach conducts the validation on the training data, which oftentimes is not a good estimate of the prediction error. Hence, it requires a predetermined cardinality bound. Instead, we propose to select variables with respect to the cross-validation value. The process is formulated as a mixed-integer program with the sparsity becoming subject of the optimization. Usually, a cross-validation is used to select the best model out of a few options. With the proposed program the best model out of all possible models is selected. Since the cross-validation is a much better estimate of the prediction error, the model can select the best sparsity itself.
The thesis is concluded with an extensive simulation study which provides evidence that discrete optimization can be used to produce highly valuable predictive models with the cross-validation subset selection regression almost always producing the best results.
This dissertation deals with consistent estimates in household surveys. Household surveys are often drawn via cluster sampling, with households sampled at the first stage and persons selected at the second stage. The collected data provide information for estimation at both the person and the household level. However, consistent estimates are desirable in the sense that the estimated household-level totals should coincide with the estimated totals obtained at the person-level. Current practice in statistical offices is to use integrated weighting. In this approach consistent estimates are guaranteed by equal weights for all persons within a household and the household itself. However, due to the forced equality of weights, the individual patterns of persons are lost and the heterogeneity within households is not taken into account. In order to avoid the negative consequences of integrated weighting, we propose alternative weighting methods in the first part of this dissertation that ensure both consistent estimates and individual person weights within a household. The underlying idea is to limit the consistency conditions to variables that emerge in both the personal and household data sets. These common variables are included in the person- and household-level estimator as additional auxiliary variables. This achieves consistency more directly and only for the relevant variables, rather than indirectly by forcing equal weights on all persons within a household. Further decisive advantages of the proposed alternative weighting methods are that original individual rather than the constructed aggregated auxiliaries are utilized and that the variable selection process is more flexible because different auxiliary variables can be incorporated in the person-level estimator than in the household-level estimator.
In the second part of this dissertation, the variances of a person-level GREG estimator and an integrated estimator are compared in order to quantify the effects of the consistency requirements in the integrated weighting approach. One of the challenges is that the estimators to be compared are of different dimensions. The proposed solution is to decompose the variance of the integrated estimator into the variance of a reduced GREG estimator, whose underlying model is of the same dimensions as the person-level GREG estimator, and add a constructed term that captures the effects disregarded by the reduced model. Subsequently, further fields of application for the derived decomposition are proposed such as the variable selection process in the field of econometrics or survey statistics.
Nonlocal operators are used in a wide variety of models and applications due to many natural phenomena being driven by nonlocal dynamics. Nonlocal operators are integral operators allowing for interactions between two distinct points in space. The nonlocal models investigated in this thesis involve kernels that are assumed to have a finite range of nonlocal interactions. Kernels of this type are used in nonlocal elasticity and convection-diffusion models as well as finance and image analysis. Also within the mathematical theory they arouse great interest, as they are asymptotically related to fractional and classical differential equations.
The results in this thesis can be grouped according to the following three aspects: modeling and analysis, discretization and optimization.
Mathematical models demonstrate their true usefulness when put into numerical practice. For computational purposes, it is important that the support of the kernel is clearly determined. Therefore nonlocal interactions are typically assumed to occur within an Euclidean ball of finite radius. In this thesis we consider more general interaction sets including norm induced balls as special cases and extend established results about well-posedness and asymptotic limits.
The discretization of integral equations is a challenging endeavor. Especially kernels which are truncated by Euclidean balls require carefully designed quadrature rules for the implementation of efficient finite element codes. In this thesis we investigate the computational benefits of polyhedral interaction sets as well as geometrically approximated interaction sets. In addition to that we outline the computational advantages of sufficiently structured problem settings.
Shape optimization methods have been proven useful for identifying interfaces in models governed by partial differential equations. Here we consider a class of shape optimization problems constrained by nonlocal equations which involve interface-dependent kernels. We derive the shape derivative associated to the nonlocal system model and solve the problem by established numerical techniques.
Mit diesem Territorial Science Echo werden wesentliche Facetten von Governance beleuchtet, die sich für die künftige Entwicklung der Großregion als relevant erweisen können. Es wird insbesondere dargestellt, wie thematische Kooperationen und Konflikte zur der Etablierung von Governance Strukturen beitragen. Das Paper setzt sich mit den Themen Governance im Allgemeinen, Partizipation und Wohnen sowie den Außenbeziehungen der Großregion auseinander, formuliert wesentliche Herausforderungen und Empfehlungen, und ist somit als Anregung im fachlichen Diskurs um die weitere Gestaltung des Raumentwicklungskonzeptes der Großregion zu verstehen.
Der vorliegende Sammelband geht auf die UniGR-Fachtagung Edu.GR - Europa leben lernen / Edu.GR - Apprendre à vivre l’Europe zurück, die am 20. September 2018 an der Universität Trier stattfand. Die Beiträge befassen sich aus unterschiedlichen Perspektiven – so aus Sicht der Bildungswissenschaften, der Fachdidaktiken, der Sozialwissenschaften und der Bildungspraxis – mit der Frage der Gestaltung Europas am Beispiel der Großregion. Vorgestellt und diskutiert werden neben Konzepten transnationaler Bildung auch empirische Analysen des Denkens und Handelns der Beteiligten in grenzregionalen (Aus-)Bildungskontexten sowie ausgewählte Beispiele transnationaler Bildungspraxis.
Abstract: Thermal infrared (TIR) multi-/hyperspectral and sun-induced fluorescence (SIF) approaches together with classic solar-reflective (visible, near-, and shortwave infrared reflectance (VNIR)/SWIR) hyperspectral remote sensing form the latest state-of-the-art techniques for the detection of crop water stress. Each of these three domains requires dedicated sensor technology currently in place for ground and airborne applications and either have satellite concepts under development (e.g., HySPIRI/SBG (Surface Biology and Geology), Sentinel-8, HiTeSEM in the TIR) or are subject to satellite missions recently launched or scheduled within the next years (i.e., EnMAP and PRISMA (PRecursore IperSpettrale della Missione Applicativa, launched on March 2019) in the VNIR/SWIR, Fluorescence Explorer (FLEX) in the SIF). Identification of plant water stress or drought is of utmost importance to guarantee global water and food supply. Therefore, knowledge of crop water status over large farmland areas bears large potential for optimizing agricultural water use. As plant responses to water stress are numerous and complex, their physiological consequences affect the electromagnetic signal in different spectral domains. This review paper summarizes the importance of water stress-related applications and the plant responses to water stress, followed by a concise review of water-stress detection through remote sensing, focusing on TIR without neglecting the comparison to other spectral domains (i.e., VNIR/SWIR and SIF) and multi-sensor approaches. Current and planned sensors at ground, airborne, and satellite level for the TIR as well as a selection of commonly used indices and approaches for water-stress detection using the main multi-/hyperspectral remote sensing imaging techniques are reviewed. Several important challenges are discussed that occur when using spectral emissivity, temperature-based indices, and physically-based approaches for water-stress detection in the TIR spectral domain. Furthermore, challenges with data processing and the perspectives for future satellite missions in the TIR are critically examined. In conclusion, information from multi-/hyperspectral TIR together with those from VNIR/SWIR and SIF sensors within a multi-sensor approach can provide profound insights to actual plant (water) status and the rationale of physiological and biochemical changes. Synergistic sensor use will open new avenues for scientists to study plant functioning and the response to environmental stress in a wide range of ecosystems.
Die publikationsbasierte Dissertation untersucht die Bedeutung sozialer Bewegungen für die Entwicklung der Sozialen Arbeit am Ende des 19. und den ersten Jahrzehnten des 20. Jahrhunderts als Profession und Disziplin in den USA und in Deutschland. Dabei wird die entstehende Soziale Arbeit als ‚Formbildung‘ sozialer Bewegungen verstanden und gefragt, wie sich die Bewegungen in die sich etablierende und institutionalisierende Profession und Wissenschaft Soziale Arbeit einschreiben, welche Anliegen dabei verfolgt werden und wie dadurch Wissen in der Sozialen Arbeit auch über nationalstaatliche Grenzen hinweg zirkuliert.
Die Untersuchung konzentriert sich auf Prozesse der Pädagogisierung, also unterschiedliche ‚Formbildungen des Pädagogischen‘, die die Bewegungsanliegen zum Thema von Aufklärung, (Selbst)Bildung und Pädagogik machen, und auf solche der Verwissenschaftlichung, die sich auf den Aufbau einer Wissensgrundlage zur Bearbeitung von sozialen Problemen richten und dabei alternative Formen der Wissensproduktion ausbilden. Diese Prozesse werden in drei Teilstudien – zur Charity Organization Movement und der Settlement House Movement in den USA sowie der bürgerlichen Frauenbewegung in Deutschland – in sieben Einzelbeiträgen näher untersucht. Im Mittelpunkt stehen dabei die Handlungsmethoden und das Praxisverständnis sowie Forschungskonzepte und –projekte exemplarisch ausgewählter sozialbewegter Initiativen der Sozialen Arbeit. Dabei werden unter anderem nicht-intendierte Effekte untersucht, die zum Beispiel in Konservierungen normativer Vorstellungen und Ideologien in als demokratisierend angelegten Ansätzen, aber auch in ‚differenzverstärkenden‘ Effekten bestehen können.
Ziel der Dissertation ist es, den Hochwasserschutz und das Management extremer Hoch-wasser für das Einzugsgebiet der Isar zu verbessern mit Hinblick darauf, wie sich vorhandene und neu zu schaffende Retentionsräume mit optimaler Wirkung für das gesamte Flusssystem einsetzen lassen. Dafür sind Kenntnisse über extreme Ereignisse und deren Auswirkung auf die betrachteten Einzugsgebiete notwendig. Großskalige Niederschläge in Mitteleuropa werden überwiegend durch Vb-artige Zugbahnen ausgelöst. Die Relevanz für Bayern zeigt die Auswertung des neuesten Kataloges der Vb-Zugbahnen für den Zeitraum 1959 bis 2015. In den Monaten April bis Oktober haben Vb-Zugbahnen zu ca. 30 % der beobachten Hochwasser beigetragen. Im Sommer führt sogar jedes zweite Vb-Tief zu Hochwasser. Im Donaueinzugsgebiet können 50 % der 20 größten Hochwasser direkt auf Vb-Zugbahnen zurückgeführt werden, weitere 25 % durch ähnliche Zugbahnen oder auf eine Vb aktiven Phase. Über die Hälfe der größten Hochwasser traten dabei in Bezug zu einer Serie von Vb-Tiefs auf. 60 % der Vb-Zugbahnen sind Teil einer Serie von Vb-Tiefs. Aus wiederkehrenden Niederschlägen persistenter Zugbahnen resultieren mehrgipflige Hochwasserwellen, die insbesondere für Rückhalteräume betrachtet werden müssen (DIN 19700). Die Detailuntersuchung erfolgt unter besonderer Beachtung der Untersuchungen zu den Vb-Zugbahnen. Das Isareinzugsgebiet mit 8900 km-² besitzt mit den Seen im Voralpenland große natürliche Retentionsräume und mit dem Sylvensteinspeicher im alpinen Einzugsgebiet den größten staatlichen Speicher Bayerns. Für die Wirkungsanalyse von gekoppelten Hoch-wasserrückhalteräumen in komplexen Einzugsgebieten müssen Ganglinien mit einem Nie-derschlag-Abfluss-Modell generiert werden, die den Wellenablauf des Hochwassers im ge-samten Einzugsgebiet repräsentieren. Die Dissertation analysiert, wie sich der Einsatz ver-schiedener Verfahren zur Vorgabe der Eingangsniederschläge auswirkt. Dabei liegt der Schwerpunkt der Untersuchung auf dem Niederschlagsverlauf. Es wird ein Verfahren zur Ableitung von Ganglinien aus standardisierten beobachteten Niederschlagsverläufen entwi-ckelt. Die Hochwasserganglinien, generiert aus synthetischen Niederschlagsverläufen der Bemessung, werden am Beispiel des Sylvensteinspeichers mit den drei größten abgelaufe-nen Hochwasserereignissen verglichen und diskutiert, ob mit dem neuen Verfahren die Cha-rakteristik der beobachten Hochwasser besser wiedergeben wird. Der Fokus liegt dabei auf der Wellenüberlagerung. Es kann für das ganze Gebiet gezeigt werden, dass die mit der neuen Methode standardisierten beobachteten Niederschlagsverläufe besser geeignet sind, die Wellenüberlagerung wiederzugeben, da zeitliche Unterschiede durch die Staueffekte an den Alpen berücksichtigt werden, wie sie bei Vb-Zugbahn geprägten Niederschlägen entste-hen. Es kann daher bei ähnlichen Fragestellungen empfohlen werden, diese Methode in der Praxis als Variante hinzuzuziehen, um die natürlichen Prozesse repräsentativer zu beschrei-ben. Für die Simulation mit dem N-A-Modell LARSIM werden die Unsicherheiten durch Varianten-rechnungen gezeigt. Es hat sich herausgestellt, dass nicht nur der Niederschlagsverlauf und die Vorbedingungen des Ereignisses eine große Auswirkung auf die Kalibrierung der Ab-flussbeiwerte im N-A-Modell haben, sondern auch das gewählte Flood-Routing-Verfahren und die Gerinnerauheit. Schließlich wird die Bewertung der potenziellen Standorte durchgeführt. Es wird berechnet, wo das Hochwasser zurückgehalten werden muss, um sowohl eine lokale Reduktion des Hochwasserscheitels, als auch gleichzeitig eine möglichst große Schutzwirkung für das Ge-samtsystem zu ermöglichen. Priorisiert werden Rückhaltestandorte, die praktisch umsetzbar sind und den größten Nutzen haben. Die Untersuchung einer Doppelwelle, die durch eine Serie von Vb-Zugbahnen entstehen kann, zeigt, wie die Einschätzung potenzieller Standorte verändern kann. Der alpine und zum Teil der voralpine Raum reagieren mit kurzen steilen Ganglinien und sind gegenüber Doppelwellen weniger sensitiv, weil kaum Wellenüberlagerung entsteht. Für den Sylvensteinspeicher, der im alpinen Raum liegt, können daher kurze Niederschlagspausen für eine schnelle Entlastung des Speicherraumes genutzt werden. Un-terhalb von Seen mit einem großen Retentionsvermögen erzeugen Doppelwellen aufgrund der langen Retentionsäste durch die Wellenüberlagerung deutlich höhere Abflüsse als Ein-zelwellen. Rückhalt an der oberen Isar ist unter diesen Kriterien am optimalsten. Empfohlene Maßnahmen - ohne Bauaufwand - konnten bereits umgesetzt werden und verbessern den Hochwasserschutz und das Hochwassermanagement an der Isar. Die Auswertungen zeigen, dass in den Monaten April, Mai, September und Oktober die Hochwasserereignisse in Folge von Vb-Zugbahnen im Zuge der Klimaveränderung häufiger und in den Sommermonaten extremer werden könnten.
This thesis is focused on improving the knowledge on a group of threatened species, the European cave salamanders (genus Hydromantes). There are three main sections gathering studies dealing with different topics: Ecology (first part), Life traits (second part) and Monitoring methodologies (third part). First part starts with the study of the response of Hydromantes to the variation of climatic conditions, analysing 15 different localities throughout a full year (CHAPTER I; published in PEERJ in August 2015). After that, the focus moves on identify which is the operative temperature that these salamander experience, including how their body respond to variation of environmental temperature. This study was conducted using one of the most advanced tool, an infrared thermocamera, which gave the opportunity to perform detailed observation on salamanders body (CHAPTER II; published in JOURNAL OF THERMAL BIOLOGY in June 2016). In the next chapter we use the previous results to analyse the ecological niche of all eight Hydromantes species. The study mostly underlines the mismatch between macro- and microscale analysis of ecological niche, showing a weak conservatism of ecological niches within the evolution of species (CHAPTER III; unpublished manuscript). We then focus only on hybrids, which occur within the natural distribution of mainland species. Here, we analyse if the ecological niche of hybrids shows divergences from those of parental species, thus evaluating the power of hybrids adaptation (CHAPTER IV; unpublished manuscript). Considering that hybrids may represent a potential threat for parental species (in terms of genetic erosion and competition), we produced the first ecological study on an allochthonous mixed population of Hydromantes, analysing population structure, ecological requirements and diet. The interest on this particular population mostly comes by the fact that its members are coming from all three mainland Hydromantes species, and thus it may represent a potential source of new hybrids (CHAPTER V; accepted in AMPHIBIA-REPTILIA in October 2017). The focus than moves on how bioclimatic parameters affect species within their distributional range. Using as model species the microendemic H. flavus, we analyse the relationship between environmental suitability and local abundance of the species, also focusing on all intermediate dynamics which provide useful information on spatial variation of individual fitness (CHAPTER VI; submitted to SCIENTIFIC REPORTS in November 2017). The first part ends with an analysis of the interaction between Hydromantes and Batracobdella algira leeches, the only known ectoparasite for European cave salamanders. Considering that the effect of leeches on their hosts is potentially detrimental, we investigated if these ectoparasites may represent a further threat for Hydromantes (CHAPTER VII; submitted to INTERNATIONAL JOURNAL FOR PARASITOLOGY: PARASITES AND WILDLIFE in November 2017). The second part is related to the reproduction of Hydromantes. In the first study we perform analyses on the breeding behaviour of several females belonging to a single population, identifying differences and similarities occurring in cohorting females (CHAPTER VIII; published in NORTH-WESTERN JOURNAL OF ZOOLOGY in December 2015). In the second study we gather information from all Hydromantes species, analysing size and development of breeding females, and identifying a relationship between breeding time and climatic conditions (CHAPTER IX; submitted to SALAMANDRA in June 2017). In the last part of this thesis, we analyse two potential methods for monitoring Hydromantes populations. In the first study we evaluate the efficiency of the marking method involving Alpha tags (CHAPTER X; published in SALAMANDRA in October 2017). In the second study we focus on evaluating N-mixtures models as a methodology for estimating abundance in wild populations (CHAPTER XI; submitted to BIODIVERSITY & CONSERVATION in October 2017).
The dissertation deals with methods to improve design-based and model-assisted estimation techniques for surveys in a finite population framework. The focus is on the development of the statistical methodology as well as their implementation by means of tailor-made numerical optimization strategies. In that regard, the developed methods aim at computing statistics for several potentially conflicting variables of interest at aggregated and disaggregated levels of the population on the basis of one single survey. The work can be divided into two main research questions, which are briefly explained in the following sections.
First, an optimal multivariate allocation method is developed taking into account several stratification levels. This approach results in a multi-objective optimization problem due to the simultaneous consideration of several variables of interest. In preparation for the numerical solution, several scalarization and standardization techniques are presented, which represent the different preferences of potential users. In addition, it is shown that by solving the problem scalarized with a weighted sum for all combinations of weights, the entire Pareto frontier of the original problem can be generated. By exploiting the special structure of the problem, the scalarized problems can be efficiently solved by a semismooth Newton method. In order to apply this numerical method to other scalarization techniques as well, an alternative approach is suggested, which traces the problem back to the weighted sum case. To address regional estimation quality requirements at multiple stratification levels, the potential use of upper bounds for regional variances is integrated into the method. In addition to restrictions on regional estimates, the method enables the consideration of box-constraints for the stratum-specific sample sizes, allowing minimum and maximum stratum-specific sampling fractions to be defined.
In addition to the allocation method, a generalized calibration method is developed, which is supposed to achieve coherent and efficient estimates at different stratification levels. The developed calibration method takes into account a very large number of benchmarks at different stratification levels, which may be obtained from different sources such as registers, paradata or other surveys using different estimation techniques. In order to incorporate the heterogeneous quality and the multitude of benchmarks, a relaxation of selected benchmarks is proposed. In that regard, predefined tolerances are assigned to problematic benchmarks at low aggregation levels in order to avoid an exact fulfillment. In addition, the generalized calibration method allows the use of box-constraints for the correction weights in order to avoid an extremely high variation of the weights. Furthermore, a variance estimation by means of a rescaling bootstrap is presented.
Both developed methods are analyzed and compared with existing methods in extensive simulation studies on the basis of a realistic synthetic data set of all households in Germany. Due to the similar requirements and objectives, both methods can be successively applied to a single survey in order to combine their efficiency advantages. In addition, both methods can be solved in a time-efficient manner using very comparable optimization approaches. These are based on transformations of the optimality conditions. The dimension of the resulting system of equations is ultimately independent of the dimension of the original problem, which enables the application even for very large problem instances.
Gegenstand der Dissertation ist die Geschichte und Manifestation des Nationaltheaters in Japan, der Transfer einer europäischen Kulturinstitution nach und deren Umsetzungsprozess in Japan, welcher mit der Modernisierung Japans ab Mitte des 19. Jahrhunderts begann und erst hundert Jahre später mit der Eröffnung des ersten Nationaltheaters 1966 endete. Dazu werden theaterhistorische Entwicklungen, Veränderungen in der Theaterproduktion und -architektur in Bezug auf die Genese eines japanischen Nationaltheaters beleuchtet. Das Ergebnis zeigt, dass sich die Institution Nationaltheater in seiner japanischen kulturellen Translation bzw. Manifestation wesentlich von den vom Land selbst als Model anvisierten Pendants in Europa in Inhalt, Organisations- und Produktionsstruktur unterscheidet. Kulturell übersetzt wurde allein die Hülle der europäischen Institution. Das erste Nationaltheater in Japan manifestiert sich als eine von der Regierung im Rahmen des Denkmalschutzgesetztes initiierte und bestimmte, spezifisch japanische Variante eines Nationaltheaters, die unter dem Management von staatlichen Angestellten und Beamten den Erhalt traditioneller Künste in dafür ausgerichteten Bühnen zur Aufgabe hat. Nationaltheaterensemble gibt es nicht, die Produktionen werden mit Schauspielern kommerzieller Theaterunternehmen realisiert. Der lange Prozess dieser Genese liegt in der nicht vorhandenen Theaterförderung seitens der Regierung und der eher zurückhaltenden Haltung der Theaterwelt gegenüber einem staatlich betriebenen Theater begründet. Das Hüllen-Konzept des ersten Nationaltheaters diente, genau wie dessen Management durch Beamte, als Prototyp für die fünf weiteren bis 2004 eröffneten Nationaltheater in Japan, welche als Spartentheater der spezifisch japanischen Vielfalt an Theaterformen, auch in ihrer Bühnenarchitektur Rechnung tragen.
Die A4-Strategie versucht, eine Antwort auf die Frage zu geben, ob es in der modernen Medienlandschaft optimale und effiziente Kommunikationsstrategien gibt, deren Erfolg nicht von der Höhe des Budgets abhängig ist und die gleichzeitig eine hohe Kundenbindung bewirken und eine effiziente Auswahl der Kommunikationsinstrumente sichert. Dies ist gerade für KMUs von besonderer Bedeutung, die sich in einem komplexen und globalisierten Marktumfeld bewegen. Die Marketingkommunikation ist nicht nur ein unvermeidliches Werkzeug, um die Verkaufszahlen zu steigern. Sie bedarf heutzutage auch einer durchdachten Strategie. Denn es wird erst eine erfolgreiche Interaktion zwischen diesen Partnern (Unternehmen und Kunden) stattfinden, wenn sowohl ein optimaler Unternehmenswert als auch ein Kundenwert generiert wird. Die A4-Strategie hilft zugleich dabei, Antworten auf die für eine optimale Marketingkommunikation relevante Fragen zu finden: Wer kann einkaufen? Wer kauft tatsächlich ein? Was sind die relevanten Informationen über den, der tatsächlich einkauft? Anhand der Antworten auf diese Frage wird ermittelt, wo und wie die potentielle Kundschaft besser akquiriert und wo und wie die bestehende Kundschaft optimal betreut werden kann. Dieses Konzept bietet eine strukturierte Herangehensweise und Vorgehensweise, um eine Kommunikationsstrategie je nach Situation zu entwickeln. Sie ist somit keine fertige Lösung, sondern schafft sie Rahmen für ein methodisches Entscheidungsprozess. Sie hilft zudem situationsadäquat Entscheidungen zu treffen und Handlungen vorzunehmen, die diese Entscheidungen konsequent umzusetzen.
Leeches can parasitize many vertebrate taxa. In amphibians, leech parasitism often has potential detrimental effects including population decline. Most of studies on the host-parasite interactions involving leeches and amphibians focus on freshwater environments, while they are very scarce for terrestrial amphibians. In this work, we studied the relationship between the leech Batracobdella algira and the European terrestrial salamanders of the genus Hydromantes, identifying environmental features related to the presence of the leeches and their possible effects on the hosts. We performed observation throughout Sardinia (Italy), covering the distribution area of all Hydromantes species endemic to this island. From September 2015 to May 2017, we conducted >150 surveys in 26 underground environments, collecting data on 2629 salamanders and 131 leeches. Water hardness was the only environmental feature correlated with the presence of B. algira, linking this leech to active karstic systems. Leeches were more frequently parasitizing salamanders with large body size. Body Condition Index was not significantly different between parasitized and non-parasitized salamanders. Our study shows the importance of abiotic environmental features for host-parasite interactions, and poses new questions on complex interspecific interactions between this ectoparasite and amphibians.
Optimal Control of Partial Integro-Differential Equations and Analysis of the Gaussian Kernel
(2018)
An important field of applied mathematics is the simulation of complex financial, mechanical, chemical, physical or medical processes with mathematical models. In addition to the pure modeling of the processes, the simultaneous optimization of an objective function by changing the model parameters is often the actual goal. Models in fields such as finance, biology or medicine benefit from this optimization step.
While many processes can be modeled using an ordinary differential equation (ODE), partial differential equations (PDEs) are needed to optimize heat conduction and flow characteristics, spreading of tumor cells in tissue as well as option prices. A partial integro-differential equation (PIDE) is a parital differential equation involving an integral operator, e.g., the convolution of the unknown function with a given kernel function. PIDEs occur for example in models that simulate adhesive forces between cells or option prices with jumps.
In each of the two parts of this thesis, a certain PIDE is the main object of interest. In the first part, we study a semilinear PIDE-constrained optimal control problem with the aim to derive necessary optimality conditions. In the second, we analyze a linear PIDE that includes the convolution of the unknown function with the Gaussian kernel.
The trophic niche is a life trait that identifies the consumer’s position in a local food web. Several factors, such as ontogeny, competitive ability and resource availability contribute in shaping species trophic niches. To date, information on the diet of European Hydromantes salamanders are only available for a limited number of species, no dietary studies have involved more than one species of the genus at a time, and there are limited evidences on how multiple factors interact in determining diet variation. In this study we examined the diet of multiple populations of six out of the eight European cave salamanders, providing the first data on the diet for five of them. In addition, we assessed whether these closely related generalist species show similar diet and, for each species, we tested whether season, age class or sex influence the number and the type of prey consumed. Stomach condition (empty/full) and the number of prey consumed were strongly related to seasonality and to the activity level of individuals. Empty stomachs were more frequent in autumn, in individuals far from cave entrance and in juveniles. Diet composition was significantly different among species. Hydromantes imperialis and H. supramontis were the most generalist species; H. flavus and H. sarrabusensis fed mostly on Hymenoptera and Coleoptera Staphylinidae, while H. genei and H. ambrosii mostly consumed Arachnida and Endopterygota larvae. Furthermore, we detected seasonal shifts of diet in the majority of the species examined. Conversely, within each species, we did not find diet differences between females, males and juveniles. Although being assumed to have very similar dietary habits, here Hydromantes species were shown to be characterized by a high divergence in diet composition and in the stomach condition of individuals.
Ziel der hier bereitgestellten Anforderungskataloge ist es, einen Überblick über die Anforderungen zu geben, welche an FDM-Services in den Geisteswissenschaften und in der Psychologie gestellt werden. Dies soll Hochschulen und außeruniversitären Forschungseinrichtungen die Möglichkeit geben, ihre eigenen Servicekataloge um FDM-Services zu erweitern, welche auf die spezifischen Bedarfe der Forschenden in diesen Disziplinen abgestimmt sind. Zudem sollen diese Anforderungskataloge als Vorlage für die Entwicklung weiterer Anforderungskataloge dienen, welche die fachspezifischen FDM-Services in anderen Fachdisziplinen spezifizieren.
In the context of accelerated global socio-environmental change, the Water-Energy-Food Nexus has received increasing attention within science and international politics by promoting integrated resource governance. This study explores the scientific nexus debates from a discourse analytical perspective to reveal knowledge and power relations as well as geographical settings of nexus research. We also investigate approaches to socio-nature relations that influence nexus research and subsequent political implications. Our findings suggest that the leading nexus discourse is dominated by natural scientific perspectives and a neo-Malthusian framing of environmental challenges. Accordingly, the promoted cross-sectoral nexus approach to resource governance emphasizes efficiency, security, future sustainability, and poverty reduction. Water, energy, and food are conceived as global trade goods that require close monitoring, management and control, to be achieved via quantitative assessments and technological interventions. Within the less visible discourse, social scientific perspectives engage with the social, political, and normative elements of the Water-Energy-Food Nexus. These perspectives criticize the dominant nexus representation for itsmanagerial, neoliberal, and utilitarian approach to resource governance. The managerial framing is critiqued for masking power relations and social inequalities, while alternative framings acknowledge the political nature of resource governance and socio-nature relations. The spatial dimensions of the nexus debate are also discussed. Notably, the nexus is largely shaped by western knowledge, yet applied mainly in specific regions of the Global South. In order for the nexus to achieve integrative solutions for sustainability, the debate needs to overcome its current discursive and spatial separations. To this end, we need to engage more closely with alternative nexus discourses, embrace epistemic pluralism and encourage multi-perspective debates about the socio-nature relations we actually intend to promote.
Background: The growing production and use of engineered AgNP in industry and private households make increasing concentrations of AgNP in the environment unavoidable. Although we already know the harmful effects of AgNP on pivotal bacterial driven soil functions, information about the impact of silver nanoparticles (AgNP) on the soil bacterial community structure is rare. Hence, the aim of this study was to reveal the long-term effects of AgNP on major soil bacterial phyla in a loamy soil. The study was conducted as a laboratory incubation experiment over a period of 1 year using a loamy soil and AgNP concentrations ranging from 0.01 to 1 mg AgNP/kg soil. Effects were quantified using the taxon-specific 16S rRNA qPCR.
Results: The short-term exposure of AgNP at environmentally relevant concentration of 0.01 mg AgNP/kg caused significant positive effects on Acidobacteria (44.0%), Actinobacteria (21.1%) and Bacteroidetes (14.6%), whereas beta-Proteobacteria population was minimized by 14.2% relative to the control (p ≤ 0.05). After 1 year of exposure to 0.01 mg AgNP/kg diminished Acidobacteria (p = 0.007), Bacteroidetes (p = 0.005) and beta-Proteobacteria (p = 0.000) by 14.5, 10.1 and 13.9%, respectively. Actino- and alpha-Proteobacteria were statistically unaffected by AgNP treatments after 1-year exposure. Furthermore, a statistically significant regression and correlation analysis between silver toxicity and exposure time confirmed loamy soils as a sink for silver nanoparticles and their concomitant silver ions.
Conclusions: Even very low concentrations of AgNP may cause disadvantages for the autotrophic ammonia oxidation (nitrification), the organic carbon transformation and the chitin degradation in soils by exerting harmful effects on the liable bacterial phyla.
Wie erleben Schüler*innen die vorhandenen demokratischen Mitgestaltungsmöglichkeiten im Unterricht? Welche Bereitschaft, den Entwicklungsprozess mitzutragen, gibt es in der Schulgemeinschaft? Welche Widerstände gilt es zu beachten und wo liegen bisher ungenutzte Potentiale und Ideen für die Innovation von Schule und Unterricht?
„Wie cool wäre es, wenn wir Schüler einen eigenen TV-Sender hätten?“, schwärmt Sophie. „Vielleicht lieber ein Webchannel, damit man unsere Berichte von überall sehen kann,“ ruft Max. „Auf jeden Fall sollte es um Themen gehen, die uns Schülern wichtig sind“, sind sich die beiden einig. Gemeinsam grübeln sie: Ist das rechtlich überhaupt möglich? Wer kann uns dabei helfen?...
Schule entwickeln – ohne feste Tagesordnung, ohne starres Rednerpodium mit festgelegten Beiträgen und alle Mitglieder der Schulgemeinschaft können frei entscheiden, was sie wann tun möchten und werden mit ihren Ideen und Anliegen gehört. Klingt das sowohl interessant, als auch ein wenig verrückt? Open Space als Werkzeug zur demokratischen Schulentwicklung macht es möglich.
External capital plays an important role in financing entrepreneurial ventures, due to limited internal capital sources. An important external capital provider for entrepreneurial ventures are venture capitalists (VCs). VCs worldwide are often confronted with thousands of proposals of entrepreneurial ventures per year and must choose among all of these companies in which to invest. Not only do VCs finance companies at their early stages, but they also finance entrepreneurial companies in their later stages, when companies have secured their first market success. That is why this dissertation focuses on the decision-making behavior of VCs when investing in later-stage ventures. This dissertation uses both qualitative as well as quantitative research methods in order to provide answer to how the decision-making behavior of VCs that invest in later-stage ventures can be described.
Based on qualitative interviews with 19 investment professionals, the first insight gained is that for different stages of venture development, different decision criteria are applied. This is attributed to different risks and goals of ventures at different stages, as well as the different types of information available. These decision criteria in the context of later-stage ventures contrast with results from studies that focus on early-stage ventures. Later-stage ventures possess meaningful information on financials (revenue growth and profitability), the established business model, and existing external investors that is not available for early-stage ventures and therefore constitute new decision criteria for this specific context.
Following this identification of the most relevant decision criteria for investors in the context of later-stage ventures, a conjoint study with 749 participants was carried out to understand the relative importance of decision criteria. The results showed that investors attribute the highest importance to 1) revenue growth, (2) value-added of products/services for customers, and (3) management team track record, demonstrating differences when compared to decision-making studies in the context of early-stage ventures.
Not only do the characteristics of a venture influence the decision to invest, additional indirect factors, such as individual characteristics or characteristics of the investment firm, can influence individual decisions. Relying on cognitive theory, this study investigated the influence of various individual characteristics on screening decisions and found that both investment experience and entrepreneurial experience have an influence on individual decision-making behavior. This study also examined whether goals, incentive structures, resources, and governance of the investment firm influence decision making in the context of later-stage ventures. This study particularly investigated two distinct types of investment firms, family offices and corporate venture capital funds (CVC), which have unique structures, goals, and incentive systems. Additional quantitative analysis showed that family offices put less focus on high-growth firms and whether reputable investors are present. They tend to focus more on the profitability of a later-stage venture in the initial screening. The analysis showed that CVCs place greater importance on product and business model characteristics than other investors. CVCs also favor later-stage ventures with lower revenue growth rates, indicating a preference for less risky investments. The results provide various insights for theory and practice.
Sample surveys are a widely used and cost effective tool to gain information about a population under consideration. Nowadays, there is an increasing demand not only for information on the population level but also on the level of subpopulations. For some of these subpopulations of interest, however, very small subsample sizes might occur such that the application of traditional estimation methods is not expedient. In order to provide reliable information also for those so called small areas, small area estimation (SAE) methods combine auxiliary information and the sample data via a statistical model.
The present thesis deals, among other aspects, with the development of highly flexible and close to reality small area models. For this purpose, the penalized spline method is adequately modified which allows to determine the model parameters via the solution of an unconstrained optimization problem. Due to this optimization framework, the incorporation of shape constraints into the modeling process is achieved in terms of additional linear inequality constraints on the optimization problem. This results in small area estimators that allow for both the utilization of the penalized spline method as a highly flexible modeling technique and the incorporation of arbitrary shape constraints on the underlying P-spline function.
In order to incorporate multiple covariates, a tensor product approach is employed to extend the penalized spline method to multiple input variables. This leads to high-dimensional optimization problems for which naive solution algorithms yield an unjustifiable complexity in terms of runtime and in terms of memory requirements. By exploiting the underlying tensor nature, the present thesis provides adequate computationally efficient solution algorithms for the considered optimization problems and the related memory efficient, i.e. matrix-free, implementations. The crucial point thereby is the (repetitive) application of a matrix-free conjugated gradient method, whose runtime is drastically reduced by a matrx-free multigrid preconditioner.
Die Vermittlung des Grauens
(2018)
Im Rahmen meiner zweiteiligen Dissertation „Die Vermittlung des Grauens“ untersuchte ich das Einsatzpotential von Multimedia-Technologien an museal aufbereiteten Originalschauplätzen des Opfergedenkens in Frankreich und Deutschland. Vordergründig stand die Klärung der Frage, ob die heute verfügbaren technischen Hilfsmittel die traditionelle Vermittlungsarbeit sinnvoll ergänzen können. Die Forts Douaumont und Vaux in Verdun und die Alte Synagoge Essen schienen mir aufgrund ihrer stark divergierenden Musealisierungen für eine dahingehende Analyse besonders geeignet. Vor Ort widmete ich mich zum einen dem Prozess der „Vergegenwärtigung der Vergangenheit am nahezu originalbelassenen Erinnerungsort durch Multimediaguides“ und begab mich ebenso auf „Spurensuche in der Alten Synagoge Essen“, da die Neukonzeptionierung der Stätte sämtliche Erinnerungen an das örtliche Geschehen im Nationalsozialismus überzeichnet hat. Diese Umstände wirken sich dementsprechend auch unterschiedlich auf die Authentizität des jeweiligen Ortes aus, worauf das dortige Konzept reagieren und für einen angemessenen Ausgleich sorgen muss. Um die Aussagekraft demgemäß zu fördern, bieten sich heutzutage insbesondere Technologien wie Audio- und Multimediaguides an, deren Potential anhand der genannten Objekte überprüft wurde. Neben diese mittlerweile schon traditionellen Maßnahmen, traten im Laufe der Zeit weitere Präsentationsmöglichkeiten wie die Touchscreen-, Virtual oder Augmented Reality-Technologien, der QR-Code, die Nahbereichskommunikation NFC und die sogenannten Museums-Apps, die ebenso zur Sprache kamen. Dieser Umstand trägt sich nicht zuletzt dadurch, dass bei der musealen Vermittlungsarbeit das Zusammenwirken von formalen Bildungsträgern und informellen Lernorten immer mehr an Bedeutung gewinnt. Die große Herausforderung hierbei ist die altersgerechte Darbietung der Inhalte.
This study examines to what extent a banking crisis and the ensuing potential liquidity shortage affect corporate cash holdings. Specifically, how do firms adjust their liquidity management prior to and during a banking crisis when they are restricted in their financing options? These restrictions might not result from firm-specific characteristics but also incorporate the effects of certain regulatory requirements. I analyse the real effects of indicators of a potential crisis and the occurrence of a crisis event on corporate cash holdings for both unregulated and regulated firms from 31 different countries. In contrast to existing studies, I perform this analysis on the basis of a long observation period (1997 to 2014 respectively 2003 to 2014) using multiple crisis indicators (early warning signals) and multiple crisis events. For regulated firms, this study makes use of a unique sample of country-specific regulatory information, which is collected by hand for 15 countries and converted into an ordinal scale based on the severity of the regulation. Regulated firms are selected from a single industry: Real Estate Investment Trusts. These firms invest in real estate properties and let these properties to third parties. Real Estate Investment Trusts that comply with the aforementioned regulations are exempt from income taxation and are punished for a breach, which makes this industry particularly interesting for the analysis of capital structure decisions.
The results for regulated and unregulated firms are mostly inconclusive. I find no convincing evidence that the degree of regulation affects the level of cash holdings for regulated firms before and during a banking crisis. For unregulated firms, I find strong evidence that financially constrained firms have higher cash holdings than unconstrained firms. Further, there is no real evidence that either financially constrained firms or unconstrained firms increase their cash holdings when observing an early warning signal. In case of a banking crisis, the results differ for univariate tests and in panel regressions. In the univariate setting, I find evidence that both types of firms hold higher levels of cash during a banking crisis. In panel regressions, the effect is only evident for financially unconstrained firms from the US, and when controlling for financial stress, it is also apparent for financially constrained US firms. For firms from Europe, the results are predominantly inconclusive. For banking crises that are preceded by an early warning signal, there is only evidence for an increase in cash holdings for unconstrained US firms when controlling for financial stress.
In the present study a non-motion-stabilized scanning Doppler lidar was operated on board of RV Polarstern in the Arctic (June 2014) and Antarctic (December 2015– January 2016). This is the first time that such a system measured on an icebreaker in the Antarctic. A method for a motion correction of the data in the post-processing is presented.
The wind calculation is based on vertical azimuth display (VAD) scans with eight directions that pass a quality control. Additionally a method for an empirical signal-tonoise ratio (SNR) threshold is presented, which can be calculated for individual measurement set-ups. Lidar wind profiles are compared to total of about 120 radiosonde profiles and also to wind measurements of the ship.
The performance of the lidar measurements in comparison with radio soundings generally shows small root mean square deviation (bias) for wind speed of around 1ms-1(0.1ms-1) and for wind direction of around 10 (1). The post-processing of the non-motion-stabilized data shows comparably high quality to studies with motion-stabilized systems.
Two case studies show that a flexible change in SNR threshold can be beneficial for special situations. Further the studies reveal that short-lived low-level jets in the atmospheric boundary layer can be captured by lidar measurements with a high temporal resolution in contrast to routine radio soundings. The present study shows that a non-motionstabilized Doppler lidar can be operated successfully on an
icebreaker. It presents a processing chain including quality control tests and error quantification, which is useful for further measurement campaigns.
Salivary alpha-amylase (sAA) influences the perception of taste and texture, features both relevant in acquiring food liking and, with time, food preference. However, no studies have yet investigated the relationship between basal activity levels of sAA and food preference. We collected saliva from 57 volunteers (63% women) who we assessed in terms of their preference for different food items. These items were grouped into four categories according to their nutritional properties: high in starch, high in sugar, high glycaemic index, and high glycaemic load. Anthropometric markers of cardiovascular risk were also calculated. Our findings suggest that sAA influences food
preference and body composition in women. Regression analysis showed that basal sAA activity is inversely associated with subjective but not self-reported behavioural preference for foods high in sugar. Additionally, sAA and subjective preference are associated with anthropometric markers of cardiovascular risk. We believe that this pilot study points to this enzyme as an interesting candidate to consider among the physiological factors that modulate eating behaviour.
Possibilités et opportunités d’une organisation démocratique du système scolaire luxembourgeois
(2018)
« Aujourd’hui, le socialisme et la démocratie ne sont plus de simples questions réservées aux partis politiques, ce sont des questions vitales. L’école et les enseignants devront s’en saisir (...) et donner au peuple de demain, par un enseignement solide, mais surtout par une éducation formatrice, les moyens de remplir sa mission principale : régner ensemble. » – ein luxemburger Schulfreund, 1920
« Lorsque l’on réfléchit aux perspectives du développement scolaire, notre action doit être guidée par la vision d’une école démocratique, d’une école vivante dans un État démocratique ainsi que par la conception de l’être humain à laquelle elle est associée. Dans ses processus de conception et dans sa vie quotidienne, l’école de demain doit elle-même être une mise en pratique de la démocratie. » (Hartmut Wenzel)
Comment les élèves vivent-ils les possibilités actuelles de participation démocratique dans l’enseignement ? La communauté scolaire est-elle prête à porter le processus de développement ? Quelles résistances faut-il prendre en compte et où se trouvent les potentiels et les idées inexploités pour innover dans l’école et dans l’enseignement ?
« Ce serait vraiment cool si les élèves avaient leur propre chaîne de télévision, non ? », s’extasie Sophie. « Peut-être plutôt une web TV, pour qu’on puisse voir nos reportages de partout dans le monde », s’exclame Max. « En tout cas, il faut que ça parle de sujets qui sont importants pour les élèves » : sur ce point, les deux collégiens sont d’accord. Ensemble, ils se creusent les méninges : pour commencer, est-ce possible juridiquement ? Qui peut nous aider ?
Développer l’école – sans ordre du jour fixe, sans tribune ni interventions programmées. Tous les membres de la communauté scolaire peuvent décider librement ce qu’ils veulent faire et quand ils veulent le faire. Leurs idées et leurs souhaits sont écoutés. Tout cela vous semble à la fois intéressant et un peu fou ? Grâce à la méthode du forum ouvert, outil de développement scolaire démocratique, c’est possible.
Die räumliche Entwicklung von Städten und Regionen wird durch Trends wie Klimawandel, demographische Veränderungen und Strukturwandel beeinflusst, welche nicht an Verwaltungsgrenzen aufhören, sondern die Entwicklung großflächiger Gebiete bestimmen. Außerdem weisen Grenzräume häufig funktionale und thematische Verflechtungen auf, die über die nationalen Grenzen hinweg bestehen. Damit verbunden sind ein regelmäßiger Austausch und Abhängigkeiten zwischen Grenzräumen und deren Bewohnern. Daher ist die Koordination der grenzüberschreitenden Raumentwicklung entscheidend für eine zukunftsorientierte und nachhaltige räumliche Entwicklung. Aufgrund seiner hohen Bedeutung wird dieses Thema von europäischen Wissenschaftlern in der ersten Ausgabe der Themenhefte Borders in Perspective aus verschiedenen Perspektiven beleuchtet.
Les carnets paraissent biannuellement et offrent aux dirigeant(e)s des écoles ainsi qu’au personnel des fondements théoriques et du matériel pratique pour la mise en oeuvre d’un développement scolaire démocratique. Chaque publication traite d’une méthode de l’éducation à la démocratie ou d’une question stratégique du développement scolaire. Les carnets en langue allemande sont mis à disposition des écoles luxembourgeoises en version imprimée. Tous le matériel ainsi que la version en langue française sont disponibles en ligne.
Academic achievement is a central outcome in educational research, both in and outside higher education, has direct effects on individual’s professional and financial prospects and a high individual and public return on investment. Theories comprise cognitive as well as non-cognitive influences on achievement. Two examples frequently investigated in empirical research are knowledge (as a cognitive determinant) and stress (as a non-cognitive determinant) of achievement. However, knowledge and stress are not stable, what raises questions as to how temporal dynamics in knowledge on the one hand and stress on the other contribute to achievement. To study these contributions in the present doctoral dissertation, I used meta-analysis, latent profile transition analysis, and latent state-trait analysis. The results support the idea of knowledge acquisition as a cumulative and long-term process that forms the basis for academic achievement and conceptual change as an important mechanism for the acquisition of knowledge in higher education. Moreover, the findings suggest that students’ stress experiences in higher education are subject to stable, trait-like influences, as well as situational and/or interactional, state-like influences which are differentially related to achievement and health. The results imply that investigating the causal networks between knowledge, stress, and academic achievement is a promising strategy for better understanding academic achievement in higher education. For this purpose, future studies should use longitudinal designs, randomized controlled trials, and meta-analytical techniques. Potential practical applications include taking account of students’ prior knowledge in higher education teaching and decreasing stress among higher education students.
A matrix A is called completely positive if there exists an entrywise nonnegative matrix B such that A = BB^T. These matrices can be used to obtain convex reformulations of for example nonconvex quadratic or combinatorial problems. One of the main problems with completely positive matrices is checking whether a given matrix is completely positive. This is known to be NP-hard in general. rnrnFor a given matrix completely positive matrix A, it is nontrivial to find a cp-factorization A=BB^T with nonnegative B since this factorization would provide a certificate for the matrix to be completely positive. But this factorization is not only important for the membership to the completely positive cone, it can also be used to recover the solution of the underlying quadratic or combinatorial problem.rnrnIn addition, it is not a priori known how many columns are necessary to generate a cp-factorization for the given matrix. The minimal possible number of columns is called the cp-rank of A and so far it is still an open question how to derive the cp-rank for a given matrix. Some facts on completely positive matrices and the cp-rank will be given in Chapter 2.rnrnMoreover, in Chapter 6, we will see a factorization algorithm, which, for a given completely positive matrix A and a suitable starting point, computes the nonnegative factorization A=BB^T. The algorithm therefore returns a certificate for the matrix to be completely positive. As introduced in Chapter 3, the fundamental idea of the factorization algorithm is to start from an initial square factorization which is not necessarily entrywise nonnegative, and extend this factorization to a matrix for which the number of columns is greater than or equal to the cp-rank of A. Then it is the goal to transform this generated factorization into a cp-factorization.rnrnThis problem can be formulated as a nonconvex feasibility problem, as shown in Section 4.1, and solved by a method which is based on alternating projections, as proven in Chapter 6.rnrnOn the topic of alternating projections, a survey will be given in Chapter 5. Here we will see how to apply this technique to several types of sets like subspaces, convex sets, manifolds and semialgebraic sets. Furthermore, we will see some known facts on the convergence rate for alternating projections between these types of sets. Considering more than two sets yields the so called cyclic projections approach. Here some known facts for subspaces and convex sets will be shown. Moreover, we will see a new convergence result on cyclic projections among a sequence of manifolds in Section 5.4.rnrnIn the context of cp-factorizations, a local convergence result for the introduced algorithm will be given. This result is based on the known convergence for alternating projections between semialgebraic sets.rnrnTo obtain cp-facrorizations with this first method, it is necessary to solve a second order cone problem in every projection step, which is very costly. Therefore, in Section 6.2, we will see an additional heuristic extension, which improves the numerical performance of the algorithm. Extensive numerical tests in Chapter 7 will show that the factorization method is very fast in most instances. In addition, we will see how to derive a certificate for the matrix to be an element of the interior of the completely positive cone.rnrnAs a further application, this method can be extended to find a symmetric nonnegative matrix factorization, where we consider an additional low-rank constraint. Here again, the method to derive factorizations for completely positive matrices can be used, albeit with some further adjustments, introduced in Section 8.1. Moreover, we will see that even for the general case of deriving a nonnegative matrix factorization for a given rectangular matrix A, the key aspects of the completely positive factorization approach can be used. To this end, it becomes necessary to extend the idea of finding a completely positive factorization such that it can be used for rectangular matrices. This yields an applicable algorithm for nonnegative matrix factorization in Section 8.2.rnNumerical results for this approach will suggest that the presented algorithms and techniques to obtain completely positive matrix factorizations can be extended to general nonnegative factorization problems.
