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Promoting organic nucleation of diclofenac : hydrophobic interfacial interactions drive self-assembly
No full textWe compare the pH-triggered nucleation of the pharmaceutical diclofenac in bulk solution and at the air–water interface, using a combination of cryo-transmission electron microscopy, surface-specific spectroscopy and microscopy, and molecular dynamics simulations. In solution, simulation data reveal diclofenac forms dynamically ordered, liquid-like pre-nucleation clusters (PNCs), following a nonclassical nucleation pathway. At the air–water interface, nucleation occurs earlier during the titration process. The promoted nucleation is attributed to the interfacial enrichment of protons at this hydrophobic interface, elevated interfacial apparent pKa for diclofenac, as well as the interface-induced ordered diclofenac–water structures. While hydrophobic interactions drive the first air–diclofenac–water layer, further diclofenac molecules tend to separate from water by forming hydrogen-bonded dimers, characteristic of the crystal structure. These findings provide molecular-level insights into organic nucleation, highlighting the importance of hydrophobic interfaces in controlling the process, with potential implications for various applications in pharmaceutical and materials science.publishe
Lower limb injuries and their association with anthropometrics : an observational study of 381 German elite youth football players
No full textBackground
Youth football players are at high risk of lower limb injuries, which can affect performance and long-term career development. However, epidemiological data on injury patterns in German elite youth football remain limited. This study aims to (1) provide an overview of lower limb injuries in German elite youth football academies and (2) investigate the association between anthropometric factors, particularly genu varum, and injury risk.
Methods
This cross-sectional study included 381 healthy male football players (aged 10–23 years) from two German elite youth academies between 2021 and 2023. Injury history from the most recent full league season, including pre-season and regular season matches, was recorded. Anthropometric assessments included body composition and intercondylar distance of the knee (ICD) to evaluate genu varum.
Results
A total of 140 lower limb injuries were documented, resulting in a cumulative injury frequency of 0.39 and an incidence of 1.2 injuries per 1,000 h. Most injuries were muscle-tendon injuries in the thigh (36.4%) and ligament injuries in the ankle (35.0%). Injury hot spots included lateral ligament tears in the ankle (30.0%) and muscle injuries within a triangle of the hamstrings (12.9%), quadriceps (10.7%), and adductors (11.4%) in the thigh. Injury frequency significantly increased from age 13 (p =.013; OR = 2.29), particularly in the thigh (p =.027; OR = 3.28). Regression analysis revealed a significant correlation between age (p =.038; coefficient of variation (COV) = -0.07) and ICD (p =.003; COV = -0.01) on the number of injuries, suggesting a potential link between genu varum and increased injury risk.
Conclusion
This study provides the first structured overview of lower limb injuries in two German elite youth football academies and their association with anthropometric data. The findings highlight age-related injury patterns and suggest a potential link between genu varum and injury risk, underlining the need for targeted injury prevention strategies. Establishing a systematic, long-term injury surveillance system in youth football is essential for developing evidence-based interventions to reduce injury risk and support player development.publishe
Characterizing correlated noise with single-qubit operations
No full textSpatially correlated noise poses a significant challenge to fault-tolerant quantum computation by breaking the assumption of independent errors. Existing methods such as cycle benchmarking and quantum process tomography can characterize noise correlations but require substantial resources. We propose straightforward and efficient techniques to detect and quantify these correlations by leveraging collective phenomena arising from environmental correlations in a qubit register. In these techniques, single-qubit state preparations, single-qubit gates, and single-qubit measurements, combined with classical postprocessing, suffice to uncover correlated relaxation and dephasing. Specifically, we use that correlated relaxation is connected to the superradiance effect, which we show to be accessible by single-qubit measurements. Analogously, the established parity oscillation protocol can be refined to quantify correlated dephasing without requiring the preparation of complex and entangled states.publishe
The politics of reproduction and the realities of obstetric violence in Ghana
No full textIntroduction: Violence during childbirth, widely conceptualized as obstetric violence, is a precarious and pressing public health concern. These include brutal acts of physical violence, humiliation, forced medical care, as well as denial of treatment. The World Health Organization recognizes it as torturous acts that put the lives of many women at risk. This paper explores the dynamics of obstetric violence through the birth narratives of women in rural and urban Ghana.
Methods: Qualitative phenomenological research was conducted in eight rural and urban public health facilities in the Western and Ashanti Regions of Ghana. A total of 35 women (20 from urban areas and 15 from rural areas) who had given birth in the last 24 months at health facilities were purposively selected and interviewed between August 2021 and February 2022 using a semi-structured interview guide. Thematic data analysis was conducted using the NVivo qualitative data analysis software.
Results: The findings of the study revealed that there is a pervasive culture of violence surrounding childbirth, with women describing their childbirth memories with sadness and regret. Obstetric violence manifests in the form of physical violence, where sutures after episiotomies are performed without anesthesia, and women are beaten or slapped for their inability to push. In addition, women are grossly abandoned, usually during the second stage of labor. Sometimes, the entire care is halted when healthcare workers are provoked or feel that the women do not make enough efforts. In some cases, women are even left to deliver unassisted. Yelling, shouting, and verbal abuse of women were very dominant, and this particularly instilled fear in women, which prevented them from seeking help in critical situations, thereby increasing the risk of birth complications. Teenage mothers and HIV-positive women are predominantly discriminated against. Psychological trauma, mistrust in health institutions, and preference for unskilled birth attendants are the major consequences of obstetric violence.
Discussion: Overall, obstetric violence is a major setback in Ghana's effort to achieve the global target of reduced maternal mortality. There is a critical need for the Ghanaian government to develop interventions to tackle this challenge.publishe
DFG Final Report (Abschlussbericht) "Biochemistry of thermophilic degradation of C1 and C2 compounds in Thermacetogenium phaeum"
No full textpublishe
Characteristics of ChatGPT users from Germany: Implications for the digital divide from web tracking data
No full textA major challenge of our time is reducing disparities in access to and effective use of digital technologies, with recent discussions highlighting the role of AI in exacerbating the digital divide. We examine user characteristics that predict usage of the AI-powered conversational agent ChatGPT. We combine behavioral and survey data in a web tracked sample of N = 1376 German citizens to investigate differences in ChatGPT activity (usage, visits, and adoption) during the first 11 months from the launch of the service (November 30, 2022). Guided by a model of technology acceptance (UTAUT-2), we examine the role of socio-demographics commonly associated with the digital divide in ChatGPT activity and explore further socio-political attributes identified via stability selection in Lasso regressions. We confirm that lower age and higher education affect ChatGPT usage, but do not find that gender or income do. We find full-time employment and more children to be barriers to ChatGPT activity. Using a variety of social media was positively associated with ChatGPT activity. In terms of political variables, political knowledge and political self-efficacy as well as some political behaviors such as voting, debating political issues online and offline and political action online were all associated with ChatGPT activity, with online political debating and political self-efficacy negatively so. Finally, need for cognition and communication skills such as writing, attending meetings, or giving presentations, were also associated with ChatGPT engagement, though chairing/organizing meetings was negatively associated. Our research informs efforts to address digital disparities and promote digital literacy among underserved populations by presenting implications, recommendations, and discussions on ethical and social issues of our findings.publishe
Exploring the dark matter disk model in dwarf galaxies : Insights from the LITTLE THINGS sample
No full textWe conducted an analysis of the velocity field of dwarf galaxies in the sample collected by the Local Irregulars That Trace Luminosity Extremes and The H I Nearby Galaxy Survey (LITTLE THINGS) and focused on deriving 2D velocity maps that encompass the transverse and radial velocity fields. Within the range of radial distances in which velocity anisotropies are sufficiently small for the disk to be considered supported by rotation and where the warped geometry of the disk can be neglected, we reconstructed the rotation curve while taking the effect of the asymmetric drift into account. To fit the rotation curves, we employed the standard halo model and the dark matter disk (DMD) model, which assumes that dark matter is primarily confined to the galactic disks and can be traced by the distribution of H I. Interestingly, our analysis revealed that the fits from the DMD model are statistically comparable to those obtained using the standard halo model, but the inferred masses of the galaxies in the DMD model are approximately 10 to 100 times lower than the masses inferred in the standard halo model. In the DMD model, the inner slope of the rotation curve is directly related to a linear combination of the surface density profiles of the stellar and gas components, which generally exhibit a flat core. Consequently, the observation of a linear relation between the rotation curve and the radius in the central disk regions is consistent with the framework of the DMD model.publishe
Teenage childbearing and the welfare state
No full textTeenage childbearing is a common incident in developed countries. However, teenage births are much more likely in the USA than in any other industrialized country. Most of these births are delivered by female teenagers from low-income families. The hypothesis put forward here is that the welfare state (a set of redistributive institutions) has a significant influence on teenage childbearing behavior. We develop an economic theory of parental investments and the risky sexual behavior of teenagers. The model is estimated to fit stylized facts about income inequality, intergenerational mobility, and the sexual behavior of teenagers in the USA. The welfare state institutions are introduced via tax and public education expenditure functions derived from US data. In a quantitative experiment, we impose Norwegian taxes and education spending in the economic environment. The Norwegian welfare state institutions go a long way in explaining the differences in teenage birth rates between the USA and Norway.publishe
Positively charged specificity site in cyclin B1 is essential for mitotic fidelity
No full textPhosphorylation of substrates by cyclin-dependent kinases (CDKs) is the driving force of cell cycle progression. Several CDK-activating cyclins are involved, yet how they contribute to substrate specificity is still poorly understood. Here, we discover that a positively charged pocket in cyclin B1, which is exclusively conserved within B-type cyclins and binds phosphorylated serine- or threonine-residues, is essential for correct execution of mitosis. HeLa cells expressing pocket mutant cyclin B1 are strongly delayed in anaphase onset due to multiple defects in mitotic spindle function and timely activation of the E3 ligase APC/C. Pocket integrity is essential for APC/C phosphorylation particularly at non-consensus CDK1 sites and full in vitro ubiquitylation activity. Our results support a model in which cyclin B1’s pocket facilitates sequential substrate phosphorylations involving initial priming events that assist subsequent pocket-dependent phosphorylations even at non-consensus CDK1 motifs.publishe
The long way from raw data to NAM-based information : Overview on data layers and processing steps
No full textToxicological test methods generate raw data and provide instructions on how to use these to determine a final outcome such as a classification of test compounds as hits or non-hits. The data processing pipeline provided in the test method description is often highly complex. Usually, multiple layers of data, ranging from a machine-generated output to the final hit definition, are considered. Transition between each of these layers often requires several data processing steps. As changes in any of these processing steps can impact the final output of new approach methods (NAMs), the processing pipeline is an essential part of a NAM description and should be included in reporting templates such as the ToxTemp. The same raw data, processed in different ways, may result in different final outcomes that may affect the readiness status and regulatory acceptance of the NAM, as an altered output can affect robustness, performance, and relevance. Data management, processing, and interpretation are therefore important elements of a comprehensive NAM definition. We aim to give an overview of the most important data levels to be considered during the development and application of a NAM. In addition, we illustrate data processing and evaluation steps between these data levels. As NAMs are increasingly standard components of the spectrum of toxicological test methods used for risk assessment, awareness of the significance of data processing steps in NAMs is crucial for building trust, ensuring acceptance, and fostering the reproducibility of NAM outcomes.publishe