University of Konstanz
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Cytomegalovirus (CMV), oxidative stress, and inflammation : implications for immunosenescence and age-related diseases in the MARK-AGE population
No full textCytomegalovirus (CMV) drives immunosenescence, while its reactivation is associated with inflammation and oxidative stress. This study investigates the interplay between CMV, oxidative stress and inflammation in a cohort of 2065 age-stratified individuals randomly recruited from the general population (RASIG), as part of the MARK-AGE study, to better understand the role of CMV in immunosenescence and its potential impact on age-related diseases. CMV IgG titers were associated with oxidative stress, antioxidant, and inflammatory biomarkers. Stepwise-linear regression identified positive associations with age, BMI, apolipoprotein J (ApoJ/Clu), ceruloplasmin, α-2-macroglobulin, proteasome peptidase activity, and malondialdehyde, and negative associations with α-tocopherol, selenium, and vitamin D. Notably, the associations with ApoJ/Clu and proteasome peptidase activity represent novel findings that point to a potential involvement of proteostasis dysregulation and cellular stress responses in CMV-related immune alterations. Quartile-based analyses revealed significantly lower antioxidant levels (α-tocopherol, selenium, ascorbic acid and vitamin D) and higher oxidative stress markers (plasma 8-isoprostanes, malondialdehyde) in the highest quartile (Q4) compared to lower quartiles. Inflammatory markers (homocysteine, ceruloplasmin and α-2-macroglobulin) ApoJ/Clu and proteasome peptidase activity were elevated in Q4. This group also exhibited a higher prevalence of cardiovascular diseases, hypertension, and diabetes. This study highlights a link between CMV IgG titers, oxidative stress, inflammation, and the prevalence of cardiovascular and metabolic diseases. Our findings suggest that CMV may contribute to immunosenescence through mechanisms involving redox imbalance and dysregulation of protein degradation pathways. Further research is needed to explore the role of CMV reactivation in aging, and its impact on age-related metabolic and cardiovascular diseases.publishe
The effect of social structure on vocal flexibility in monk parakeets
No full textThe social complexity hypothesis argues that communicative complexity arises as a result of social complexity, with this occurring through mechanisms including plasticity and selection. Most research to date has focused on ultimate drivers of repertoire size, for example finding that cooperative breeding species exhibit larger repertoires. Until this date, to our knowledge, no study has focused on individual-level drivers of vocal diversity. Here, we examine social networks and vocalizations in wild colonial-nesting monk parakeets (Myiopsitta monachus). We recorded social networks for 337 individuals, relatedness for 100 individuals and matched these with 5599 vocalizations from 229 individuals over 2 years. Overall, we found that all individuals exhibited high contact-call diversity; however, individual-level diversity increased with age in 2020 and with number of nest mates in 2021. Call similarity was not predicted by relatedness, but individuals with stronger affiliative bonds had more dissimilar calls, suggesting an active process to sound unique among close associates. Finally, females had more diverse repertoires, producing relatively fewer contact calls across years and individuals living in larger groups had more diverse repertoires in 2021. Our results demonstrate a multi-faceted social influence on call content, diversity and repertoire diversity, exhibiting how fine-scale variation in social structure can influence expressed vocal complexity.publishe
Exploring Laypersons’ Experiences With a Mobile Symptom Checker App as an Interface Between eHealth Literacy, Health Literacy, and Health-Related Behavior : Qualitative Interview Study
No full textBackground: Symptom checkers aim to help users recognize medical symptoms and recommend actions. However, they are not yet reliable for self-triage or diagnostics. Health literacy plays a role in their use, but the process from symptom recognition to health care consultation remains unclear.
Objective: This qualitative observatory study explored how laypersons use symptom checkers, focusing on the process of use, entry points and outcomes, and the role of health literacy. Laypersons are defined as individuals who are neither medical professionals nor developers of such apps. Three research questions were addressed: (1) How do such users describe the process of using symptom checkers? (2) What are entry points and possible outcomes of symptom checker app use? (3) How are health literacy and eHealth literacy expressed during the use of symptom checker apps?
Methods: As part of the Ethical, Legal, and Social Implications of Symptom Checker Apps in Primary Health Care project, 15 laypersons (n=9, 60% female and n=6, 40% male; mean age 30.7, SD 13.6 years) were interviewed about their experiences with the symptom checker Ada. The interviews were analyzed using an integrative approach combining social positioning, agency, and the Rubicon model as a heuristic framework.
Results: App use follows a cyclic process comprising 4 steps: motivation (influenced by biography and context), intention formation (assigning a purpose), intention implementation (recruiting resources), and evaluation (transforming interactions into health-related insights). Biographical, social, and contextual factors shape process initiation. Users use symptom checkers for 3 main purposes: understanding their condition, receiving recommendations for action, and documenting or communicating health-related information. Each purpose requires specific planning and integration into health-related behaviors drawing on personal, social, and technological resources. Evaluation depends on contextual factors, app outputs, and the outcomes of users’ health-related actions. Users assess whether the app aligns with their expectations, condition severity, and previous experiences, with health literacy playing a critical role in validation processes.
Conclusions: Symptom checker use is a complex, cyclic process shaped by context, biography, and health literacy. Users are motivated by health concerns influenced by personal, social, and contextual factors, with trust and attitudes impacting initial engagement. Intention formation reflects a balance between user skills and context, where app outputs inform decisions but may not always lead to action, especially in ambiguous situations. Users rely on personal resources and social networks to integrate app use into health-related behaviors, highlighting the limitations of symptom checkers in providing social or empathetic support. Symptom checkers have the potential to serve as an interface between users and health care, but future development must address the complexity of their use to unlock this potential.
International Registered Report Identifier (IRRID): RR2-10.2196/34026publishe
Julius Caesar, Altered : The Travels of Tragedy under Neoclassical Conditions (Voltaire, Conti)
No full textpublishe
Luminescent Dinuclear Chromium(III) Complexes with Ferromagnetic Exchange Interactions
No full textRecent advances with luminescent mononuclear chromium(III) complexes have provided important molecular design guidelines for enhancing their photoluminescence properties. Applying these modern aspects of coordination chemistry to dinuclear CrIII complexes, which are mostly not luminescent but show interesting magnetic properties, seems attractive for exploring functional coordination compounds with magnetic exchange interactions and light-induced activity. In this concept, the key structural requirements for dinuclear CrIII complexes with ferromagnetic exchange interactions and with photoluminescence properties, respectively, are analyzed. Rational merger of these key magneto-optical–structural correlations leads to new types of dinuclear CrIII complexes with ferromagnetic coupling and room temperature luminescence, and their photophysical properties make them promising photosensitizers for energy transfer. These design concepts open the door of exploring novel dinuclear CrIII complexes, which can allow the crosstalk of photophysics, photochemistry, and magnetic exchange interactions.publishe
Bridging Theory and Practice with Immersive Virtual Reality : A Study on Transfer Facilitation in VET
No full textThis study explores the potential of immersive virtual reality (IVR) to enhance knowledge transfer in vocational education, particularly in bridging the gap between academic learning and practical workplace application. The focus lies on relevant predictors for actual learning transfer, namely knowledge acquisition and the transfer-related self-efficacy. Additionally, the Cognitive Affective Model of Immersive Learning (CAMIL) is used to investigate potential predictors in IVR learning. This approach allows for empirical testing of the CAMIL and validation of its assumptions using empirical data. To address the research questions, a quasi-experimental field study was conducted with 141 retail trainees at a German vocational school. Participants were assigned to either an IVR group or a control group receiving traditional instruction. The intervention spanned four teaching sessions of 90 min each, focusing on the design of a retail sales area based on sales-promoting principles. To assess subject-related learning outcomes, a domain-specific knowledge test was developed. In addition, transfer-related self-efficacy and other relevant constructs were measured using Likert-scale questionnaires. The results show that IVR-based instruction significantly improves knowledge acquisition and transfer-related self-efficacy compared to traditional teaching methods. In terms of the CAMIL-based mechanisms, significant correlations were found between transfer-related self-efficacy and factors such as interest, motivation, academic self-efficacy, embodiment, and self-regulation. Additionally, correlations were found between knowledge acquisition and relevant predictors such as interest, motivation, and self-regulation. These findings underscore IVR’s potential to facilitate knowledge transfer in vocational school, highlighting the need for further research on its long-term effects and the actual application of learned skills in real-world settings.publishe
Species vulnerability and ecosystem fragility : A dual perspective in food webs
No full textEcosystems face intensifying threats from climate change, overexploitation, and other human pressures, emphasizing the urgent need to identify keystone species and vulnerable ones. While established network-based measures often rely on a single metric to quantify a species’ relevance, they overlook how organisms can be both carbon providers and consumers, thus playing a dual role in food webs. Here, we introduce a novel approach that assigns each species two complementary scores—an importance index quantifying their centrality as carbon source and a predatory index capturing their vulnerability. We show that species with high importance index are more likely to trigger co-extinctions upon removal, while high-robustness index species typically endure until later stages of collapse, in line with their broader prey ranges. On the other hand, low robustness index species are the most vulnerable and susceptible to extinctions. Tested on multiple food webs, our method outperforms traditional degree-based analyses and competes effectively with eigenvector-based approaches, while also providing additional insights. This scalable and data-driven approach, relying solely on interaction data, provides a cost-effective tool that complements expert classifications for prioritizing conservation efforts.publishe
Evaluation of the probability current in the stochastic path integral formalism
No full textThe probability current is a vital quantity in the Fokker-Planck description of stochastic processes. It characterizes non-equilibrium stationary states and appears in linear response calculations. We recover and review the probability current in the Onsager-Machlup functional approach to Markov processes by deriving a self- contained expression in general non-equilibrium fluctuation-dissipation relations using field theoretical methods. The derived formulas hold for non-constant drift and diffusion tensors and are explicitly evaluated in an Ornstein-Uhlenbeck process with non-reciprocal interactions specified as a harmonically bound particle in shear flow. Our work clarifies the concept of the probability current — familiar from the Fokker-Planck equation — in the path integral approach.publishe
Surface Electrons on Solid Quantum Substrates : A Brief Review
No full textIn this work an overview is given on experiments with surface electrons above the quantum solids hydrogen and neon. While two-dimensional ensembles of surface electrons on the quantum liquid superfluid helium have been studied already in great detail, investigations of electrons on quantum solids are rather sparse. Since recently electron-on-neon qubits have been shown to exhibit very long coherence times, there is a demand for understanding the conditions for a successful growth of thin solid neon films as a qubit substrate. Therefore, in this review also the triple point wetting phenomenon of the hydrogen isotopes and neon is discussed, which dominates the growth of solid films of these materials.publishe