Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases
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Investigating the Influence of Self-Control on Rule-breaking: Advancing Empirical Tests on Situational Action Theory Through Rigorous Operationalizations and Experimental Designs
No full textThis dissertation tackles a core problem in Situational Action Theory (SAT): the mismatch between SAT’s concept of self-control ability and the indicators commonly used to measure it. Prior SAT studies have primarily relied on the Low Self-Control Scale (LSCS), a tool developed for Gottfredson and Hirschi’s Self-Control Theory, not SAT. Because SAT defines self-control ability as a situational capacity, or the ability to adhere to personal morality when facing external pressures, using a trait-based LSCS produces a concept–indicator discrepancy. This misalignment limits empirical validity, creates distorted findings, and reinforces the broader “jingle problem,” where superficially identical terms mask fundamentally different concepts.
To resolve this, the dissertation argues that SAT research needs a new measure consistent with SAT’s micro-level action theory. Because SAT explains behavior through the convergence of person, setting, and moment, valid measurement requires designs that assess how individuals act in specific situations. This micro-situational perspective is often not captured through standard surveys that ask about general tendencies or retrospective behaviors detached from their settings. Instead, SAT requires designs that approximate or manipulate situational conditions while observing individual decision-making in those contexts.
The dissertation, therefore, develops a new Self-Control Ability Scale tailored to SAT’s conceptualization and tests it using research designs that create spatiotemporal convergence. These include factorial survey vignettes that systematically vary moral norms within concrete scenarios, and behavioral experiments that observe real rule-breaking opportunities. Such designs allow SAT’s action-generating mechanism to be examined under controlled situational conditions, making it possible to test when and how self-control ability matters. Through this combined measurement and design strategy, the dissertation advances a conceptually consistent and empirically rigorous approach to studying self-control within SAT
Cognitive Stimulation Therapy in mild to moderate Alzheimer’s Disease: an MRI study
Full text linkThis research endeavor aimed at understanding the mechanisms behind the effectiveness of Cognitive Stimulation Therapy (CST) in addressing cognitive challenges in Alzheimer's disease (AD) patients. The study, conducted at the Neurology Department of Cologne University Hospital, involved mild to moderate AD patients undergoing CST. Utilizing MRI, our goal was to uncover neural transformations underlying cognitive benefits observed in CST participants, thus advancing understanding of CST's therapeutic potential.
Brain plasticity refers to the brain's ability to adapt and reorganize itself in response to experiences and injuries. This process allows for the formation of new neural connections, supporting the development of new skills and improving cognitive function. CST is designed to enhance brain plasticity and promote compensatory mechanisms in individuals with cognitive decline. Building on knowledge of neuroplasticity's role in CST and its manifestation as compensatory effects in brain imaging, our study established a framework to detect resting-state compensatory effects in healthy aging and Mild Cognitive Impairment (MCI). Using graph theory analysis of resting-state functional MRI data and volumetric analyses of structural MRI, we identified compensatory regions in the brain associated with cognitive performance. Our analysis revealed increased connectivity in certain brain regions despite atrophy, suggesting a compensatory mechanism to counter cognitive decline.
These findings align with existing models of compensation in aging and neurodegeneration. Specifically, we identified regions such as the prefrontal cortex and parietal lobe showing successful compensation in MCI patients, with similarity to patterns observed in task-based compensational effect, suggesting that these regions may serve as targets for non-invasive stimulation techniques to enhance neuronal performance.
With evidence of brain plasticity-driven compensation in healthy aging and MCI, our study then focused on CST's capacity to mitigate cognitive decline in mild to moderate AD, using an eight-week CST program on patients with mild to moderate AD compared to a control group with no intervention. We evaluated changes in cognition, quality of life (QoL), and brain connectivity immediately after the intervention period and at a three-month follow-up. CST was found to significantly improve cognitive function, QoL, and neuropsychiatric measures in the intervention group compared to the control group.
Furthermore, our study examined the role of cognitive reserve in predicting response to CST, finding a significant correlation between improvement in cognition and years of education as a proxy measure for cognitive reserve. However, baseline total brain volume did not correlate with CST outcomes, suggesting that CST efficacy is not dependent on brain reserve in patients with mild to moderate AD.
Analysis of brain connectivity using functional MRI revealed enhanced connectivity between the hippocampus and memory-related regions, suggesting neuroplastic changes induced by CST. Additionally, increased connectivity in the parietal lobes is observed, consistent with compensatory mechanisms in healthy aging and prodromal AD.
Our results are suggestive of CST-induced neuronal activity, promoting compensatory neuroplasticity, particularly in regions associated with memory and self-representation. Autobiographical recall and narrative tasks incorporated into the CST program may contribute to memory enhancement and restoration of self-continuity.
Finally, we discussed the potential of Maintenance Cognitive Stimulation Therapy (MCST) as a longer-term intervention to maintain cognitive gains and prevent further decline in individuals with dementia. Overall, our findings highlight the effectiveness of CST in improving cognition, QoL, and brain connectivity in patients with mild to moderate AD, and provide further evidence for the broad recommendation of CST as a cost-effective non-pharmacological treatment approach for AD and emphasizes the need for its widespread accessibility in various settings, while underscoring the importance of further research to refine intervention strategies and understand underlying mechanisms
Assessing water vapour from state-of-the-art observations and models in the central Arctic and the impact of inversions on downwelling longwave radiation
Full text linkObservations have revealed that the rapidly warming Arctic is also moistening in certain regions and seasons. As water vapour is the strongest greenhouse gas, it contributes to the enhanced warming of the Arctic via the water vapour feedback. Water vapour estimates are uncertain in the Arctic due to the low amount of ground stations and challenges in satellite remote sensing. Thus, it is not surprising to see uncertainties in water vapour trends across reanalyses, which use these observations. In contrast to lower latitudes, Arctic humidity profiles feature inversions where the specific humidity increases with height. The representation of humidity inversions in current models and satellite products and the radiative effect of humidity inversions is poorly studied. Furthermore, the ability of ground-based microwave radiometers (MWRs) to capture humidity inversions has yet to be analyzed. The year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in the Arctic Ocean provides excellent reference water vapour observations to evaluate the water vapour products of models and satellites. Radiosonde observations are complemented by two MWRs with complementary water vapour sensitivity. The first part of this thesis includes two studies to quantify the benefit of the synergy of the two MWRs for water vapour products compared to the use of single MWRs. In the first study, the measurements of each MWR were quality controlled and atmospheric parameters, including coarse humidity profiles and integrated water vapour (IWV), were retrieved using regression and Neural Networks. The single MWR retrievals were evaluated with the MOSAiC radiosondes. In the second study, measurements from both MWRs were combined in a Neural Network approach to exploit their complementary moisture sensitivity. The synergy benefit was determined by comparing the errors computed in the synergy evaluation to those of the single MWR retrievals. The synergy reduces lower tropospheric specific humidity errors by 50 % and the root mean squared error of IWV by 15 % over a wide atmospheric moisture range. Additionally, the vertical resolution of the specific humidity profile is improved by a factor of two in the lower troposphere. In the second part of the thesis, the water vapour products from the MWR synergy and the radiosondes were used as reference to evaluate the water vapour from four state-of-the-art models (two global reanalyses, a regional and a global weather forecast model) and two satellite products. A particular focus was on analyzing the representation of humidity inversions with respect to radiosondes. Strong negative IWV and specific humidity biases in moist conditions were found for the satellite data. The models underestimate the lower tropospheric specific humidity in the cold seasons, except for the lowest 100 m. The presence of surface-based inversions is well captured by the models and the MWR synergy but not by the satellite observations. Elevated inversions are missed by both the MWR synergy and satellite observations. Additionally, all tested data sets tend to underestimate the number of inversions per profile and the inversion strength but overestimate the vertical extent (depth) of inversions. Then, radiative transfer simulations for clear sky cases were used to analyze the sensitivity of downwelling longwave radiation (DLR) to water vapour within humidity inversions. Therefore, the radiative effect of humidity inversions was also quantified. The sensitivity tests with artificial humidity inversion strength modifications revealed that in most cases the radiation emitted from water vapour within an inversion only has a notable impact on DLR when the inversion is located in the lower troposphere. In most of the clear sky cases, the surface-based inversion contributed 60-100 % to the total radiative effect of humidity inversions, which can reach up to 16 W m-2. Additionally, we quantified DLR deviations resulting from using specific humidity profiles of the different models and observations (ground- and space-based) as input to the radiative transfer simulations. With the DLR based on the radiosonde profiles as reference, DLR deviations exceed 5 W m-2 in some cases but are mostly lower. The humidity profiles of the MWR synergy resulted in one of the smallest DLR deviations, demonstrating the high quality of the MWR humidity profiles. The deviations could be equally attributed to differences in lower tropospheric specific humidity and IWV. The results suggest that the IWV and the lower tropospheric specific humidity, and therefore the near-surface humidity inversions, are equally important for accurate DLR calculations
Moss-derived complement factor H variants attenuate light-induced retinal degeneration
Full text linkAge related macular degeneration (AMD) is one of the leading causes of vision loss. Various factors are
part of the complex disease etiology including genetic risk factors. Polymorphisms in the Complement
factor H (CFH) gene are the most prevalent genetic factors for increased AMD risk. CFH is an important
regulator of the alternative complement pathway, which is part of the innate immune response. A miss
regulation of the complement system is also related to other diseases, like atypical hemolytic
syndrome, that were already successfully treated with CFH supplementation.
In this study, two moss-derived human CFH variants were tested in a light-induced mouse model of
retinal degeneration that is reproducing important aspects of AMD. Two different variants, CPV-101
and CPV-104, which differ in their glycosylation were injected intravitreal one day prior light exposure.
The mice were exposed to bright white light for 30 min with an intensity of 10.000 lux.
Both variants were capable of reducing the complement pathway activity, resulting in less formation
of membrane attack complex. Additionally microgliosis and Müller cell reactivity was reduced, leading
to less pro inflammatory cytokine and chemokine signaling. Finally, the number of TUNEL positive cells
as well as the retinal thinning was attenuated in mice treated with CPV-101 or CPV-104. This is a
promising outcome for a possible future use of moss derived CFH as a therapeutic strategy
Skalendokumentation Überzeugungen zur Inklusion (InkÜ)
Full text linkProfessionelle Überzeugungen zur inklusiven Bildung von (angehenden) Lehrpersonen stellen einen zentralen Bestandteil ihrer professionellen Kompetenz dar und sind wesentlich für die Umsetzung von Inklusion, bzw. für den Erfolg der gemeinsamen Beschulung aller Schüler*innen. Das Skaleninventar Überzeugungen zur inklusiven Bildung (InkÜ) besteht aus sieben Skalen zu unterschiedlichen Inhalts- und Anforderungsbereichen inklusiven Unterrichts. Zugrunde liegt ein Rahmenmodell mit dem verschiedene Ebenen der Begriffsdefinition von Inklusion mit professionellen Anforderungen an Lehrkräfte im Bereich inklusiver Bildung verknüpft werden. Die Skalen wurden bereits für unterschiedliche Stichproben von angehenden bis zu berufstätigen Lehrkräften verschiedener Lehramtstypen erfolgreich eingesetzt
Schrift-Bild-Lesen. Ausgangspunkte, Theorien und Modelle
No full textLesen ist ein komplexes Phänomen, das gilt in besonderem Maße für das Lesen von Texten, die Schrift und Bild miteinander kombinieren. In der gegenwärtigen multimodal dominierten, digitalen Medienkultur vollzieht sich ein Wandel des Lesens auf mehreren Ebenen: Es erweitern sich nicht nur das Spektrum der Lesemedien (neben Print- treten Digitalmedien) und die Texte selbst (multimodale Kommunikate als Regelfall, insbesondere Schrift-Bild-Kombinationen), sondern auch rezeptionsseitig Lesemodalitäten und Lesekontexte. Für die Leseforschung und Literacy-Forschung stellt sich in diesem Zusammenhang die Frage, wie die veränderten Leseprozesse und die neuen Lesepraktiken im Rahmen der Theoriebildung und Lesekompetenz-Modellierung eine adäquate Berücksichtigung finden können. Im Fokus dieses Einführungsbeitrags steht die Frage, wie Texte gelesen werden, die Schrift und Bild kombinieren. Der Beitrag formuliert Problemstellungen des Schrift-Bild-Lesens und gibt einen Überblick über grundlegende Begriffe und ausgewählte Theorien, die sich als Grundlage und Ausgangspunkt für eine Modellierung des Schrift-Bild-Lesens anbieten. Im Fokus stehen hierbei sprach-, literatur- und medienwissenschaftliche Perspektiven sowie pädagogisch-didaktische Implikationen
Integrated (acute) Health Care in rural Long-Term Care Facilities
Full text linkThe demographic ageing of the population constitutes a major societal and healthcare challenge, particularly in rural regions where demographic shifts are more pronounced and healthcare infrastructures are often under-resourced. Long-term care facility (LTCF) residents, who are typically characterised by multimorbidity, frailty, and complex care needs, require continuous, coordinated, and high-quality medical attention. However, rural healthcare systems frequently face significant structural barriers, including shortages of primary and specialist care providers, limited emergency service capacity, and geographic isolation—factors that collectively exacerbate the risk of care discontinuities and inappropriate hospital transfers.
This dissertation investigates the implementation and potential of integrated care models as a strategy to address these challenges in rural LTCFs. Emphasising acute health risk situations, the study explores the experiences, needs, and decision-making processes of frontline healthcare professionals—specifically nurses and paramedics—who play a critical role in managing emergency care pathways. Through a multi-method approach, this research identifies the structural, organisational, and professional factors that influence emergency responses and examines how integrated care frameworks can be tailored to the rural LTCF context.
The central aim is to develop a theoretically grounded and empirically informed model of integrated care that enhances continuity, quality of care (QoC), and professional satisfaction while addressing the specific needs of rural healthcare systems. The findings offer valuable insights for the strategic development of sustainable, person-centred care structures and contribute to the broader discourse on ageing, rural health, and interprofessional collaboration in long-term care settings.
The dissertation was written as a cumulative work and consists of two research projects employing different methodologies to explore the topic. These projects resulted in two publications: the first, a systematic scoping review examines international models of integrated care in rural LTCFs. The second publication is based on interviews with professionals in rural LTCFs and discusses their perspectives on the requirements for integrated care.
The findings of this dissertation show that integrated (acute) care in rural LTCFs is a complex interplay of coordination, communication, and collaboration. It becomes clear that integrated models are still rarely implemented in practice, but offer significant potential for improving care quality and job satisfaction among healthcare professionals. The insights gained contribute to closing existing research gaps and provide valuable guidance for shaping a sustainable healthcare system in rural areas. They emphasize the need for a cultural shift towards more cross-sectoral and cooperative care, placing the needs of both residents and professionals at the center
Validierung der Totenscheindiagnosen durch klinische Obduktionen: Erkenntnisse und mögliche Konsequenzen
Full text linkDie seit langer Zeit sinkende Anzahl von klinischen Obduktionen stellt eine Gefahr für die klinische, sowie außerklinische Patienten dar. Es zeigt sich eine hohe Fehlerdiagnosenrate im Vergleich zu Totenscheindiagnose und klinischer Obduktion. Diese Dissertationschrift zeigt die häufigsten Fehldiagnosen und die zugrunde liegenden Erkrankungsbilder nicht nur von klinischen, sondern erstmals auch außerklinischem Patientengut dar. Auf mögliche Konsequenzen und deren Abwendung wird im 2. Abschnitt dieser Arbeit beschrieben
Optimizing Magnetotelluric Studies for Geothermal Exploration in Western Saudi Arabia: A Comprehensive Study of 3D Forward and Inverse Modeling Approaches
Full text linkWith its ambitious vision of 2030, Saudi Arabia has recognized the need to reduce its dependence on fossil-based energy and has taken concrete steps to diversify its energy sources. Among the priorities is the development of renewable energy, including geothermal resources. This thesis focuses on the application of Electromagnetic (EM) methods, specifically Magnetotellurics (MT) and Transient Electromagnetics (TEM), for the exploration of geothermal resources in the Al-Lith’s area, western Saudi Arabia, one of the most promising sites for geothermal development in Saudi Arabia. To comprehensively investigate and explore the prospect of geothermal resources in the area, broadband MT data covering a period range of 0.001–512 seconds were acquired at 50 locations, along with 13 TEM soundings. The phase tensor and its skew calculations revealed a complex subsurface conductivity structure, characterized by predominantly 1D/2D geoelectric behavior for short periods (< 2 sec) and a more complex 3D structure for longer periods. Prior to the inversion of the MT data, 3D MT synthetic modeling and inversion studies were carried out to assess the detectability of geothermal anomalies, optimize survey parameters, and evaluate the sensitivity of various parameter inputs applied in the 3D inversion. In order to ensure the robustness of the inversion results, extensive 3D MT inversion tests were performed. The resistivity model derived from TEM data was incorporated to optimize the 3D MT inversion. The final 3D resistivity model, with an RMS of 1.96, provides a high-resolution image of the geothermal system, delineating the heat source, convection pattern, and groundwater system. The geothermal reservoir is represented by deep elongated conductive bodies (< 20 Ωm) extending from 2.5 to over 8 km in depth. The individual protrusions above the reservoir indicate the pathways for geothermal fluids, forming convection cells from the reservoir to the surface or near the surface, potentially leading to an active geothermal surface manifestation (hot spring). The outcome of this study serves as the key input to understanding the complexity and characterization of the geothermal system of the Al-Lith region, confirming its potential for geothermal exploration and development efforts in Saudi Arabia