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Background
Identifying pain-related response patterns and understanding functional mechanisms of symptom formation and recovery are important for improving treatment.
Objectives
We aimed to replicate pain-related avoidance-endurance response patterns associated with the Fear-Avoidance Model, and its extension, the Avoidance-Endurance Model, and examined their differences in secondary measures of stress, action control (i.e., dispositional action vs. state orientation), coping, and health.
Methods
Latent profile analysis (LPA) was conducted on self-report data from 536 patients with chronic non-specific low back pain at the beginning of an inpatient rehabilitation program. Measures of stress (i.e., pain, life stress) and action control were analyzed as covariates regarding their influence on the formation of different pain response profiles. Measures of coping and health were examined as dependent variables.
Results
Partially in line with our assumptions, we found three pain response profiles of distress-avoidance, eustress-endurance, and low-endurance responses that are depending on the level of perceived stress and action control. Distress-avoidance responders emerged as the most burdened, dysfunctional patient group concerning measures of stress, action control, maladaptive coping, and health. Eustress-endurance responders showed one of the highest levels of action versus state orientation, as well as the highest levels of adaptive coping and physical activity. Low-endurance responders reported lower levels of stress as well as equal levels of action versus state orientation, maladaptive coping, and health compared to eustress-endurance responders; however, equally low levels of adaptive coping and physical activity compared to distress-avoidance responders.
Conclusions
Apart from the partially supported assumptions of the Fear-Avoidance and Avoidance-Endurance Model, perceived stress and dispositional action versus state orientation may play a crucial role in the formation of pain-related avoidance-endurance response patterns that vary in degree of adaptiveness. Results suggest tailoring interventions based on behavioral and functional analysis of pain responses in order to more effectively improve patients quality of life.
The visualization of relational data is at the heart of information visualization. The prevalence of visual representations for this kind of data is based on many real world examples spread over many application domains: protein-protein interaction networks in the field of bioinformatics, hyperlinked documents in the World Wide Web, call graphs in software systems, or co-author networks are just four instances of a rich source of relational datasets. The most common visual metaphor for this kind of data is definitely the node-link approach, which typically suffers from visual clutter caused by many edge crossings. Many sophisticated algorithms have been developed to layout a graph efficiently and with respect to a list of aesthetic graph drawing criteria. Relations between objects normally change over time. Visualizing the dynamics means an additional challenge for graph visualization researchers. Applying the same layout algorithms for static graphs to intermediate states of dynamic graphs may also be a strategy to compute layouts for an animated graph sequence that shows the dynamics. The major drawback of this approach is the high cognitive effort for a viewer of the animation to preserve his mental map. To tackle this problem, a sophisticated layout algorithm has to inspect the whole graph sequence and compute a layout with as little changes as possible between subsequent graphs. The main contribution and ultimate goal of this thesis is the visualization of dynamic compound weighted multi directed graphs as a static image that targets at visual clutter reduction and at mental map preservation. To achieve this goal, we use a radial space-filling visual metaphor to represent the dynamics in relational data. As a side effect the obtained pictures are very aesthetically appealing. In this thesis we firstly describe static graph visualizations for rule sets obtained by extracting knowledge from software archives under version control. In a different work we apply animated node-link diagrams to code-developer relationships to show the dynamics in software systems. An underestimated visualization paradigm is the radial representation of data. Though this kind of data has a long history back to centuries-old statistical graphics, only little efforts have been done to fully explore the benefits of this paradigm. We evaluated a Cartesian and a radial counterpart of a visualization technique for visually encoding transaction sequences and dynamic compound digraphs with both an eyetracking and an online study. We found some interesting phenomena apart from the fact that also laymen in graph theory can understand the novel approach in a short time and apply it to datasets. The thesis is concluded by an aesthetic dimensions framework for dynamic graph drawing, future work, and currently open issues.
In politics and economics, and thus in the official statistics, the precise estimation of indicators for small regions or parts of populations, the so-called Small Areas or domains, is discussed intensively. The design-based estimation methods currently used are mainly based on asymptotic properties and are thus reliable for large sample sizes. With small sample sizes, however, this design based considerations often do not apply, which is why special model-based estimation methods have been developed for this case - the Small Area methods. While these may be biased, they often have a smaller mean squared error (MSE) as the unbiased design based estimators. In this work both classic design-based estimation methods and model-based estimation methods are presented and compared. The focus lies on the suitability of the various methods for their use in official statistics. First theory and algorithms suitable for the required statistical models are presented, which are the basis for the subsequent model-based estimators. Sampling designs are then presented apt for Small Area applications. Based on these fundamentals, both design-based estimators and as well model-based estimation methods are developed. Particular consideration is given in this case to the area-level empirical best predictor for binomial variables. Numerical and Monte Carlo estimation methods are proposed and compared for this analytically unsolvable estimator. Furthermore, MSE estimation methods are proposed and compared. A very popular and flexible resampling method that is widely used in the field of Small Area Statistics, is the parametric bootstrap. One major drawback of this method is its high computational intensity. To mitigate this disadvantage, a variance reduction method for parametric bootstrap is proposed. On the basis of theoretical considerations the enormous potential of this proposal is proved. A Monte Carlo simulation study shows the immense variance reduction that can be achieved with this method in realistic scenarios. This can be up to 90%. This actually enables the use of parametric bootstrap in applications in official statistics. Finally, the presented estimation methods in a large Monte Carlo simulation study in a specific application for the Swiss structural survey are examined. Here problems are discussed, which are of high relevance for official statistics. These are in particular: (a) How small can the areas be without leading to inappropriate or to high precision estimates? (b) Are the accuracy specifications for the Small Area estimators reliable enough to use it for publication? (c) Do very small areas infer in the modeling of the variables of interest? Could they cause thus a deterioration of the estimates of larger and therefore more important areas? (d) How can covariates, which are in different levels of aggregation be used in an appropriate way to improve the estimates. The data basis is the Swiss census of 2001. The main results are that in the author- view, the use of small area estimators for the production of estimates for areas with very small sample sizes is advisable in spite of the modeling effort. The MSE estimates provide a useful measure of precision, but do not reach in all Small Areas the level of reliability of the variance estimates for design-based estimators.
Surveys play a major role in studying social and behavioral phenomena that are difficult to
observe. Survey data provide insights into the determinants and consequences of human
behavior and social interactions. Many domains rely on high quality survey data for decision
making and policy implementation including politics, health, business, and the social
sciences. Given a certain research question in a specific context, finding the most appropriate
survey design to ensure data quality and keep fieldwork costs low at the same time is a
difficult task. The aim of examining survey research methodology is to provide the best
evidence to estimate the costs and errors of different survey design options. The goal of this
thesis is to support and optimize the accumulation and sustainable use of evidence in survey
methodology in four steps:
(1) Identifying the gaps in meta-analytic evidence in survey methodology by a systematic
review of the existing evidence along the dimensions of a central framework in the
field
(2) Filling in these gaps with two meta-analyses in the field of survey methodology, one
on response rates in psychological online surveys, the other on panel conditioning
effects for sensitive items
(3) Assessing the robustness and sufficiency of the results of the two meta-analyses
(4) Proposing a publication format for the accumulation and dissemination of metaanalytic
evidence
Food waste is the origin of major social and environmental issues. In industrial societies, domestic households are the biggest contributors to this problem. But why do people waste food although they buy and value it? Answering this question is mandatory to design effective interventions against food waste. So far, however, many interventions have not been based on theoretical knowledge. Integrating food waste literature and ambivalence research, we propose that domestic food waste can be understood via the concept of ambivalence—the simultaneous presence of positive and negative associations towards the same attitude object. In support of this notion, we demonstrated in three pre-registered experiments that people experienced ambivalence towards non-perishable food products with expired best before dates. The experience of ambivalence was in turn associated with an increased willingness to waste food. However, two informational interventions aiming to prevent people from experiencing ambivalence did not work as intended (Experiment 3). We hope that the outlined conceptualization inspires theory-driven research on why and when people dispose of food and on how to design effective interventions.
People are increasingly concerned about how meat affects the environment, human health, and animal welfare, yet eating and enjoying meat remains a norm. Unsurprisingly, many people are ambivalent about meat—evaluating it as both positive and negative. Here, we propose that meat-related conflict is multidimensional and depends on people’s dietary group: Omnivores’ felt ambivalence relates to multiple negative associations that oppose a predominantly positive attitude towards meat, and veg*ans’ ambivalence relates to various positive associations that oppose a predominantly negative attitude. A qualitative study (N = 235; German) revealed that omnivores and veg*ans experience meat-related ambivalence due to associations with animals, sociability, sustainability, health, and sensory experiences. To quantify felt ambivalence in these domains, we developed the Meat Ambivalence Questionnaire (MAQ). We validated the MAQ in four pre-registered studies using self-report and behavioral data (N = 3,485; German, UK, representative US). Both omnivores and veg*ans reported meat-related ambivalence, but with differences across domains and their consequences for meat consumption. Specifically, ambivalence was associated with less meat consumption in omnivores (especially sensory-/animal-based ambivalence) and more meat consumption in veg*ans (especially sensory-/socially-based ambivalence). Network analyses shed further light on the nomological net of the MAQ while controlling for a comprehensive set of determinants of meat consumption. By introducing the MAQ, we hope to provide researchers with a tool to better understand how ambivalence accompanies behavior change and maintenance.
The cumulative and bidirectional groundwater-surface water (GW-SW) interaction along a stream is defined as hydrological turnover (HT) influencing solute transport and source water composition. However, HT proves to be highly variable, producing spatial exchange patterns influenced by local groundwater, geology, and topography. Hence, identifying factors controlling HT poses a challenge. We studied spatiotemporal HT variability at two reaches of a third order tributary of the river Mosel, Germany. Additionally, we sampled for silica concentrations in the stream and in the near-stream groundwater. Thus, creating snapshots of the boundary layer between ground- and surface water where HT occurs, driven by mixing processes in the hyporheic zone. We utilize an enhanced hydrograph separation method, unveiling reach differences in storage drainage based on aquifer dimension and connectivity. The data shows a site-specific negative correlation of HT with discharge, while hydraulic gradients correlate with HT only at the reach with faster catchment drainage behavior. Examining silica concentrations between stream and wells shows that silica variation increases significantly with the decrease of HT under low flow conditions at the slower draining reach. At the fast draining reach this relationship is seasonal. In Summary, our results show that stream discharge shapes the influence of HT on solute transport. Yet, reach drainage behavior shapes seasonal states of groundwater storages and can be an additional control of HT. Hence, concentration change of pollutants could be masked by HT. Thus, our findings contribute to the understanding of HT variability along streams and its ability of influencing physico-chemical stream water composition.
Although it has been demonstrated that nociceptive processing can be modulated by heterotopically and concurrently applied noxious stimuli, the nature of brain processes involved in this percept modulation in healthy subjects remains elusive. Using functional magnetic resonance imaging (fMRI) we investigated the effect of noxious counter-stimulation on pain processing. FMRI scans (1.5 T; block-design) were performed in 34 healthy subjects (median age: 23.5 years; range: 20-31 yrs.) during combined and single application (duration: 15 s; ISI=36 s incl. 6 s rating time) of noxious interdigital-web pinching (intensity range: 6-15 N) and contact-heat (45-49 -°C) presented in pseudo-randomized order during two runs separated by approx. 15 min with individually adjusted equi-intense stimuli. In order to control for attention artifacts, subjects were instructed to maintain their focus either on the mechanical or on the thermal pain stimulus. Changes in subjective pain intensity were computed as percent differences (∆%) in pain ratings between single and heterotopic stimulation for both fMRI runs, resulting in two subgroups showing a relative pain increase (subgroup P-IN, N=10) vs. decrease (subgroup P-DE, N=12). Second level and Region of Interest analysis conducted for both subgroups separately revealed that during heterotopic noxious counter-stimulation, subjects with relative pain decrease showed stronger and more widespread brain activations compared to subjects with relative pain increase in pain processing regions as well as a fronto-parietal network. Median-split regression analyses revealed a modulatory effect of prefrontal activation on connectivity between the thalamus and midbrain/pons, supporting the proposed involvement of prefrontal cortex regions in pain modulation. Furthermore, the mid-sagittal size of the total corpus callosum and five of its subareas were measured from the in vivo magnetic resonance imaging (MRI) recordings. A significantly larger relative truncus size (P=.04) was identified in participants reporting a relative decrease of subjective pain intensity during counter-stimulation, when compared to subjects experiencing a relative pain increase. The above subgroup differences observed in functional and structural imaging data are discussed with consideration of potential differences in cognitive and emotional aspects of pain modulation.
In her poems, Tawada constructs liminal speaking subjects – voices from the in-between – which disrupt entrenched binary thought processes. Synthesising relevant concepts from theories of such diverse fields as lyricology, performance studies, border studies, cultural and postcolonial studies, I develop ‘voice’ and ‘in-between space’ as the frameworks to approach Tawada’s multifaceted poetic output, from which I have chosen 29 poems and two verse novels for analysis. Based on the body speaking/writing, sensuality is central to Tawada’s use of voice, whereas the in-between space of cultures and languages serves as the basis for the liminal ‘exophonic’ voices in her work. In the context of cultural alterity, Tawada focuses on the function of language, both its effect on the body and its role in subject construction, while her feminist poetry follows the general development of feminist academia from emancipation to embodiment to queer representation. Her response to and transformation of écriture féminine in her verse novels transcends the concept of the body as the basis of identity, moving to literary and linguistic, plural self-construction instead. While few poems are overtly political, the speaker’s personal and contextual involvement in issues of social conflict reveal the poems’ potential to speak of, and to, the multiply identified citizens of a globalised world, who constantly negotiate physical as well as psychological borders.
The work of Japanese-German writer Yoko Tawada (Tawada Yōko) stands out as an example of ‘in-between’ writing. Instead of simply ‘translating’ Japanese into German and vice versa, Tawada blends both languages and cultures, often self-reflexively. As a result, poetic in-between spaces emerge, in which creative work, cultural translation, and social criticism can take place. The texts also construct in-between spaces on a formal level. For instance, the verse novels “Kasa no shitai to watashi no tsuma” (『傘の死体とわたしの妻』, 2006) and “Ein Balkonplatz für flüchtige Abende” (2016) feature both narrative progression and poetic devices (vivid imagery, association, and wordplay), defying categorization either as volumes of poetry or as novels. In addition, the in-between space of genres becomes visible in Tawada’s self-translations, which often amount to rewritings and lead to a change in genre – travel essay to novella, novel to drama, or poem to prose text. An example of this genre-transcending bilingualism as entryway to an in-between space are the texts „Die Orangerie“ (1997) and “Orenji-en nite” (「オレンジ園にて」, 1997/1998), which initially appear as a poem and its (apparently) prose translation. However, a number of textual peculiarities of both pieces point to the mutual influences between versions. Thus, I read all four examples as hybrid forms of poetry, which perform the mixing of genres, languages, and cultures that occurs in today’s world. In their cultural hybridity especially, the poems point to underlying social issues of homo- and xenophobia.