965 research outputs found
Sort by
Spatial and temporal effects of land use on temperate grassland and forest ecosystems
No full textIn this thesis, I investigate the effect of land-use intensity on the spatial distribution of plant species (in grassland and forest), as well as on changes in species abundance over time within grasslands. This thesis contains five chapters. Chapter one gives a general introduction to the topic. Chapters two to four address three research questions, presenting the corresponding results and discussions in the format of scientific publications. In a final chapter, I resume the main findings and conclude the thesis.
In chapter two, I looked at the direct and indirect effects of land-use intensity on the species-area relationship in temperate grasslands. The effect of land-use intensity on species richness has been largely studied, but not its effect on plant distribution at small spatial scale. To measure the plants distribution in space, I used the species-area relationship. I analysed in 147 agricultural grasslands how the land-use intensity directly or indirectly (via species richness) affected the plant distribution using structural equation models. This modelling approach is ideally suited to distinguish between direct effects of a variable from variables acting indirectly via others. I also looked at effects of the different land-use components (mowing, grazing and fertilisation).
In chapter three, I studied the effects of forest management on the species-area relationship in temperate forests. Forest management affects plant communities, but the direct and indirect consequences of forest management effects on the species-area relationship in forests are still little known. Using structural equation models, I looked in 149 forest plots at the impact of forest management and forest features on direct and indirect effects via species richness on the species-area relationship. We also included diameter at breast height as a proxy of forest age and tree cover as an indicator of light availability on the forest floor.
In chapter four, I assessed whether plant species trends in grasslands over 14 years can be explained by land-use intensity. Times-series looked mainly at the species richness decline over time. However, few studies looked at the abundance changes over time, particularly in a context of land-use intensity gradients. I hypothesise that land-use intensity, biotic drivers and their interactions can explain species cover trends. I thus looked at the abundance changes over time of 232 species surveyed from 2008 to 2021; plant traits, functional groups and growth form were also taken into account.
Finally, in chapter five I summarised the main results found, and compared the effects of land-use intensity and forest management on the species-area relationship in forests and grasslands. I also discuss the results of our analysis on species abundance changes over time. To conclude, I have identified possible future research ideas in fields of species-area relationship in a land-use gradient as well as for further study on species abundance trends over time
Video-based identification of surrogate endpoints in experimental bacterial infections of rainbow trout (Oncorhynchus mykiss)
Full text linkTo identify visually perceptible clinical signs that would enable timely distinction between survivors and nonsurvivors in infection experiments requiring death as experimental endpoint, rainbow trout were recorded on video after being subjected to bacterial challenge with Aeromonas salmonicida and Yersinia ruckeri. Deviations from normal morphology, behaviour and movement patterns were analysed for their potential to predict death in infected animals kept in groups of 10 fish inside small volume holding tanks (15 l). It was found that clinical signs reflecting a highly debilitated physiological state, like inability to hold an upright position or being passively dragged by a current, offer high sensitivity and specificity, but are largely inefficient in reducing the overall time an animal spends inside the experiment. A change in body shape detected in fish infected with A. salmonicida, provided high sensitivity and earlier identification of nonsurvivors. Anorexia was identified as a promising death predictor in terms of sensitivity and timely identification, but its specificity was likely to be confounded by a high level of social aggression observed between the fish. As expression of early clinical signs in form of sickness behaviour might have been strongly influenced by experimental husbandry conditions, it is assumed that optimisation of those could present an effective approach for improving applicability of surrogate endpoints in this species
Essays on bank income diversification
Full text linkThis thesis investigates the effects of bank income diversification on bank performance and systemic stability in three independent but complementary empirical studies:
The first study reviews the Glass–Steagall Act and similar specialized banking systems from a historic and macroeconomic perspective. The goal is to assess whether past specialized banking systems were introduced for financial stability concerns and whether such regimes entailed positive effects on financial stability. The historic analysis of ten countries that formerly had such regimes in place shows that such regulations were not primarily motivated by financial stability. Based on a panel of thirty high-income jurisdictions between 1970 and 2011 the study further provides an assessment of the effects of such regimes on financial stability. The results do not support the popular belief that specialized banking systems are associated with decreased crisis probability. The analysis instead yields limited evidence of a positive relation. However, the results also indicate that specialized banking systems experience less severe banking crises than universal banking regimes.
In contrast to the macro literature, a large body of empirical micro literature on the effects of bank income diversifcation exists. However, this literature provides mixed results. The second study therefore presents a meta-regression analysis on this literature, including thirty-four studies with a total of 932 regressions. The results indicate some evidence for underlying genuine effects: Diversification is generally associated with reduced risk; this includes diversification from interest income towards fee income. Diversification towards trading tends to increase profitability but decreases risk-adjusted profitability. However, the clearest result is that the findings of existing studies crucially depend on research design. The discord in the literature can partially be explained by studies not accounting for endogeneity, thus underestimating the riskiness of trading business. Furthermore, studies focusing on countries that used to separate commercial banking from investment banking tend to find a less positive relation between fee-generating activities and profitability and a more positive relation between trading and profitability. Also, samples with larger banks tend to yield more positive effects from fee-generating and trading activities on profits.
The last study analyses the effects of income diversification on large banks. The analysis is based on a panel of ninety large listed international banks from 2005 to 2015. For additional details on banks’ income structure, the data set combines information on fee and trading income, assets under management, and investment banking deal volumes. The results indicate that more diversified large banks are generally less risky and more profitable. The detailed analysis of individual bank activities indicates that fee income outside investment banking and asset management (i.e. retail fees) reduces the risk and increases the profitability of banks. The results further provide some evidence that diversification towards trading and syndicated loans underwriting decreases risk and increases profitability. In contrast, equity underwriting increases risk and decreases profitability and risk-adjusted profitability of banks.
In combination, these three studies do not support the hypothesis of specialized banking improving financial stability. Instead, the three studies give a slight indication of universal banking improving the stability of individual banks or the financial system. Overall, the results do not support limiting the business model of universal banks by legally separating commercial banking and investment banking
Soziale Integration von Menschen mit Migrationshintergrund im organisierten Vereinssport
Full text linkDie soziale Integration von Menschen mit Migrationshintergrund in den organisierten Vereinssport gilt als Schlüssel für die Einbindung in eine vielfältige Sportlandschaft und in aussersportliche Gesellschaftsbereiche. Allerdings indizieren Erkenntnisse aus zahlreichen Studien im (inter)nationalen Raum, dass die Integration von Migranten und Migrantinnen nicht per se funktioniert, sondern bestimmte Voraussetzungen erfordert. Gegenwärtig bestehen diverse Forschungslücken zu dieser Thematik. Dies betrifft insbesondere unzureichende Kenntnisse darüber, (1) welche Art von ein- und ausgrenzenden Praktiken bei Migrantinnen hinsichtlich des Zugangs zum organisierten Vereinssport auftreten; (2) wie die Vereinsmitgliedschaft von Migranten überhaupt charakterisiert ist, d.h. die sozial-integrative Einbindung in Sportvereinen; und (3) welche Bedingungsfaktoren für eine gelingende soziale Integration eine Rolle spielen. Kenntnisse hierzu wären vielversprechend, damit Akteure der Sport- und Integrationspraxis Integrationsmassnahmen zielgerichteter ansetzen bzw. weiterentwickeln können. Entsprechend ging die Dissertation in einer qualitativen Teilstudie Praktiken sozialer Grenzziehung von Migrantinnen beim Zugang zum Sport in einem interkulturellen Verein nach. Im Rahmen der quantitativen Teilstudie wurde zunächst ein theoriegeleitetes, differenziertes Messinstrument zur Erfassung der sozialen Integration im Sportvereinskontext entwickelt. Hiermit wurde das Ausmass der sozialen Integration von einheimischen und immigrierten Mitgliedern verschiedener Migrationsgenerationen untersucht, um ein besseres Verständnis über Unterschiede und Gemeinsamkeiten zu gewinnen. Parallel wurde die Rolle vielfältiger individueller sowie teilweise struktureller Merkmale für die soziale Integration immigrierter Vereinsmitglieder überprüft. Basierend auf einem Mehrebenendesign erfolgten auf interaktionaler Ebene zehn Interviews und eine Gruppendiskussion in einem interkulturellen Verein bei Bern. Auf Individuums- und Organisationsebene erfolgten standardisierte, schriftliche Befragungen mit Vereinspräsidenten von 50 Sportvereinen der Deutschschweiz und 780 Sportvereinsmitgliedern (MAlter = 20.62; 37.5 % weiblich; 38.2 % mit Migrationshintergrund).
Die Resultate der Fallstudie indizierten vielfältige veränderliche, durchlässige und miteinander verwobene Grenzziehungsprozesse. Diese können jedoch durch bedarfsgerechte Angebotsstrukturen und eine integrationsfördernde Kultur im Verein reduziert werden. Weiter lieferte eine konfirmatorische Faktorenanalyse für das entwickelte Messinstrument mit vier Integrationsdimensionen zufriedenstellende Ergebnisse (χ2/df = 2.19, RMSEA = .06, SRMR = .07, CFI = .92), sodass es vorerst angewendet werden kann. Einfaktorielle Varianzanalysen zeigten auf, dass Vereinsmitglieder der ersten Migrationsgeneration entlang dreier Integrationsdimensionen weniger stark integriert sind als einheimische und immigrierte Mitglieder der zweiten bzw. dritten Generation. Multiple lineare Regressionsanalysen verdeutlichten, dass einige individuelle Merkmale signifikant mit den Integrationsdimensionen zusammenhängen (Mitgliedschaftsdauer, elterliche Sportvereinsaktivität, Wertorientierung, bikulturelle Integrationseinstellung) und somit relevanter für die soziale Integration sind als andere (Identität, Nationalität). Die Dissertation leistet einen wertvollen methodischen und empirischen Beitrag für die Sportorganisations- und sportbezogene Migrationsforschung. Sowohl Sportvereine als auch interkulturelle Vereine stellen chancenreiche Integrationssettings des organisierten Vereinssports dar. Gleichwohl ist es für Akteure der Sport- und Integrationspraxis wegweisend, bei Integrationsmassnahmen spezifische individuelle und strukturelle Merkmale im jeweiligen Vereinskontext zu berücksichtige
Underestimated Risks? Four Studies on the Availability of Resources after Partnership Separation in Switzerland
Full text linkEthnic Conflict Management and Deliberative Transformative Moments in Srebrenica, Bosnia and Herzegovina
Full text linkThe dissertation of Simona Mameli explores the potential for deliberation in deeply divided societies by applying the innovative concept of Deliberative Transformative Moments (DTM) to discussions between conflicting groups - Serbs and Bosnjaks - in the war-torn town of Srebrenica, Bosnia and Herzegovina. The concept of DTM is used to analyze and measure the ups and downs in the level of deliberation of citizens’ discussion about political issues, getting at the internal deliberative dynamics of group discussions and shedding new light on deliberative potential of citizens of deeply divided societies
Die funktionelle Nah-Infrarot-Spektroskopie (fNIRS) und das visuell-räumliche Arbeitsgedächtnis: Experimentelle Befunde zur Sensitivität und Spezifität der Methode und zu intelligenzbedingten, interindividuellen Unterschieden der funktionellen Hirnaktivität
Full text linkMit den beiden vorliegenden Studien (Witmer et al., 2018a, 2018b) konnte gezeigt werden, dass fNIRS ausreichend sensitiv ist, um spezifische visuell-räumliche Arbeitsgedächtnisprozesse in einem für die ebendiese Arbeitsgedächtnisprozesse wichtigen frontalen Hirnareal (Brodmann Areal 8) nachzuweisen. Des Weiteren war es mittels fNIRS möglich, intelligenzbedingte Unterschiede der funktionellen Hirnaktivität zu messen. Bei Kindern im Alter zwischen 11 und 13 Jahren und jungen Erwachsenen im Alter zwischen 18 und 24 Jahren konnte gezeigt werden, dass Personen niedrigerer Intelligenz im Vergleich zu Personen höherer Intelligenz eine stärkere funktionelle Hirnaktivität während der Bearbeitung einer subjektiv einfachen, visuell-räumlichen Arbeitsgedächtnisaufgabe aufweisen
Von der Evaluation zur Implementation: Vier Studien zu internetbasierter Selbsthilfe im Kontext psychischer Gesundheit
Full text linkIn der vorliegenden Dissertation werden vier Artikel vorgestellt, welche nach dem Model of Assessment of Telemedicine applications (MAST)-Konzept kategorisiert wurden. Das MAST-Konzept stellt ein gut fundiertes Modell dar, um die Implementierung von digitalen Behandlungen zu strukturieren und multidisziplinär zu evaluieren.
Studie 1 untersucht im primären Versorgungsnetz die Wirksamkeit eines ungeleiteten Selbsthilfe-Programms in Kombination mit Care as Usual (CAU) bei verschiedenen Angststörungen. Studie 2 geht der Frage nach, ob eine internetbasierte, kognitiv-behaviorale Therapie (ICBT) als Ergänzung zu einer regulären Psychotherapie bei klinisch depressiven Personen einen zusätzlichen Nutzen liefert. Studie 3 evaluiert anhand halb-standardisierter Interviews bei depressiven Patienten, welche subjektiven Vor- als auch Nachteile einer kombinierten Therapie (blended treatment), bestehend aus internetbasierter Therapie und Face-to-Face (FtF)-Therapie, im sekundären Versorgungsnetz wahrgenommen werden. Studie 4 erhebt mittels einer Onlinebefragung innerhalb verschiedener europäischer Interessenvertreter den Stand des vorhandenen Wissens, der Empfehlungen und Erwartungen an internetbasierte Therapien sowie an Kombinationsbehandlungen für depressive Patienten.
Nach einer Einführung ins Themengebiet werden die einzelnen Artikel zusammenfassend dargestellt und kritisch reflektiert. Auf der Grundlage der Resultate der einzelnen Studien werden Möglichkeiten und Grenzen internetbasierter Interventionen im Gesundheitssystem diskutiert. In ihrer Gesamtheit liefern die Studien einen wichtigen Beitrag zur Frage der Effektivität und der Implementierung von internetbasierten Interventionen im Gesundheitswesen und zeigen auf, dass internetbasierte Ansätze eine vielversprechende Möglichkeit darstellen, die Gesundheitsversorgung zu ergänzen.The present doctoral thesis focuses on four articles, which were categorized on the basis of the Model of Assessment of Telemedicine applications (MAST). The MAST concept points out a profound concept to multidisciplinary evaluation and a structural implementation of digital treatments in mental health.
Study 1 investigated whether care as usual (CAU) plus unguided internet-based cognitive behavior therapy (ICBT) is effective for anxiety disorders compared to CAU only, when delivered in primary care. Study 2 examined the question of whether web-based interventions, when used as adjunctive treatment tools to regular psychotherapy, have an additional effect compared to regular psychotherapy for depression. Study 3 evaluates by means of a content analysis the perceived advantages and disadvantages of blended treatments in depression, a combination of ICBT and face-to-face (FtF) treatment, from the patients’ perspective in specialized mental health care in Switzerland. Study 4 evaluated in a survey aimed to exploring stakeholders’ knowledge, acceptance and expectations of digital treatments for depression.
After an introduction in the thematic field, the individual articles will be described and critically reflected in more detail. Possibilities and limits of ICBT in mental health care are discussed based on the results of the four presented articles. Taken together, the results of the studies provide an important contribution with regard to the effectiveness and the implementation of ICBT in healthcare and revealed that ICBT is a promising opportunity to complement mental healthcare
Geometric Structure Extraction and Reconstruction
Full text linkGeometric structure extraction and reconstruction is a long-standing problem in research communities including computer graphics, computer vision, and machine learning. Within different communities, it can be interpreted as different subproblems such as skeleton extraction from the point cloud, surface reconstruction from multi-view images, or manifold learning from high dimensional data. All these subproblems are building blocks of many modern applications, such as scene reconstruction for AR/VR, object recognition for robotic vision and structural analysis for big data. Despite its importance, the extraction and reconstruction of a geometric structure from real-world data are ill-posed, where the main challenges lie in the incompleteness, noise, and inconsistency of the raw input data. To address these challenges, three studies are conducted in this thesis: i) a new point set representation for shape completion, ii) a structure-aware data consolidation method, and iii) a data-driven deep learning technique for multi-view consistency. In addition to theoretical contributions, the algorithms we proposed significantly improve the performance of several state-of-the-art geometric structure extraction and reconstruction approaches, validated by extensive experimental results
Data sources:
BORIS Portal Bern Open Repository and I...BAF-Online: Proceedings of the Berner Al...HASBonline – Hefte zur Archäologie des M...Informationswissenschaft: Theorie, Metho...Jahrbuch Diakonie SchweizJournal of Eye Movement ResearchJournal of Radiation Oncology Informatic...BOP SerialsVersants. Revista suiza de literaturas r...
BORIS Theses
BORIS ThesesAccess Repository Dashboard
Do you manage BORIS Theses? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!