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Multi-valued variational inequalities for variable exponent double phase problems : comparison and extremality results
Get PDFHarvestStat Africa : harmonized subnational crop statistics for Sub-Saharan Africa
Get PDFSub-Saharan Africa faces severe agricultural data scarcity amidst high food insecurity and a large agricultural yield gap, making crop production data crucial for understanding and enhancing food systems. To address this gap, HarvestStat Africa presents the largest compilation of open-access subnational crop statistics and time-series across Sub-Saharan Africa. Based on agricultural statistics collated by USAID’s Famine Early Warning Systems Network, the subnational crop statistics are standardized and calibrated across changing administrative units to produce consistent and continuous time-series. The dataset includes 574,204 records, primarily spanning from 1980 to 2022, detailing quantity produced, harvested areas, and yields for 33 countries and 94 crop types, including key cereals in Sub-Saharan Africa such as wheat, maize, rice, sorghum, barley, millet, and fonio. This new dataset enhances our understanding of how climate variability and change influence agricultural production, supports subnational food system analysis, and aids in operational yield forecasting. As an open-source resource, it establishes a precedent for sharing subnational crop statistics to inform decision-making and modeling efforts
Multirate time integration methods and their application for coupled atmosphere-ocean models
Get PDFIn this thesis, various problems for coupled atmosphere-ocean models, in particular time integration schemes utilizing different time scales, are discussed. The different characteristics of the time integration schemes commonly applied in atmosphere and ocean models shall also be conserved for coupled models. The structure of the prognostic model equations allows the application of additive split integration schemes with different time scales. Two classes, the “Multirate Infinitesimal Step methods” and “Multirate Generalized Additive Runge—Kutta methods for N components”, are introduced and analysed. Furthermore, the problems investigated in the development of the coupled model ICONGETM are described in a more general sense and analysed for simplified coupled atmosphere-ocean models. The application of multirate methods for coupled models is demonstrated and discussed with benchmark examples for atmosphere and ocean models
Human serum albumin loaded with fatty acids reveals complex protein-ligand thermodynamics and boleadora-type solution dynamics leading to gelation
Get PDFUsing an electron paramagnetic resonance (EPR) spectroscopic strategy that has been developed for core–shell polymers, the complexity of the binding of fatty acids to human serum albumin (HSA) is characterized in detail. We unravel the internal dynamics of HSA solutions with fatty acids by applying continuous wave EPR (CW EPR) from which we derive a consistent thermodynamic interpretation about fatty acid interactions with HSA in the investigated temperature range of 5–97 °C. Additionally, data from CW EPR are corroborated by dynamic light scattering (DLS), differential scanning calorimetry (DSC) and nanoscale distance measurements using double electron–electron resonance (DEER) spectroscopy. We discuss our data in light of decades of biophysical studies on albumin and aim at drawing a complete functional and dynamic picture of HSA “at work”. This picture suggests that HSA is built from modular, rotationally decoupled domains that resemble an entangled three-piece boleadora in solution
Uneven geographies of COVID-19 II : spatialities and economic geographies in a syndemic
Get PDFThis second of three review articles on the uneven geographies of COVID-19 examines geographical research on (1) spatial patterns of the pandemic's unfolding and (2) its uneven economic geographies, considering both its direct and indirect impacts—for example, those resulting from related preventive measures. In line with this article series, it (3) concludes by discussing the relevance of the reviewed research for the syndemics approach and vice versa. Research on economic effects analyzes disruptions to global value chains, industries, labor systems, and workspaces, particularly remote work. Some studies explore how the pandemic coincided with ongoing economic transitions such as economic restructuring and shrinkage, austerity politics, digitization, and automation. Studies highlight the need to contextualize spatial inequalities within historical political-economic interdependencies, power asymmetries, and structural disparities. In doing so, geographical studies add depth to syndemic analyses of structural vulnerabilities and crisis cascades, highlighting the need for spatially sensitive assessments. Still, diverging findings at national, regional, and local levels call for comparative ex-post analyses and relational methodologies able to unpack syndemic complexities. In turn, geographers can benefit from syndemic scholars' insights into disease burdens and pre-existing structural health impacts.Gesehen am 08.04.202
Nutzung der Qualitative Comparative Analysis (QCA) in einem systematischen Review : Lessons Learned
No full textEvidence synthesis of primary studies assessing complex interventions poses challenges due to the heterogeneity of study populations,interventions,outcomes,orstudydesigns.Qualitative
comparative analysis (QCA) aims to identify conditions or combinations of conditions that lead to a speci-fic outcome and may be an appropriate instrument to deal with heterogeneity and complexity.
Objective: We aimed to describe the lessons learned when applying QCA in a systematic review on technology-based counselling interventions in dementia. Methods: The lessons learned were generated through research team reflection and discussion of the challenges and problems encountered in the process of applying the initial steps of the QCA. As the
QCA remained incomplete, a brief account of aspects to be considered when using QCA methodology for data synthesis within a systematic review is presented. Results: The lessons learned comprise the importance of clear eligibility criteria representing the core elements of interventions and the need for a consistent dataset based on sufficient reporting and suitable
publication types. We also recommend adoption of a multi-perspective view by integrating theoretical and practical knowledge. Conclusion: QCA may increase knowledge gain in systematic reviews by capturing the complexity of interventions and contexts. An adequate dataset is needed to enable systematic comparison. To achieve this, adherence to frameworks guiding the development, implementation, and evaluation of complex interventions as well as to reporting guidelines is essential
Basic mathematical skills and fraction understanding predict percentage understanding : evidence from an intelligent tutoring system
No full textResearch on fostering learning about percentages within intelligent tutoring systems (ITSs) is limited. Additionally, there is a lack of data-driven approaches for improving the design of ITS to facilitate learning about percentages. To address these gaps, we first investigated whether students' understanding of basic mathematical skills (eg, arithmetic, measurement units and geometry) and fractions within an ITS predicts their understanding of percentages. We then applied a psychological network analysis to evaluate interdependencies within the data on 44 subtopics of basic mathematical concepts, fractions and percentages. We leveraged a large-scale dataset consisting of 2798 students using the ITS bettermarks and working on approximately 4.1 million mathematical problems. We found that advanced arithmetic, measurement units, geometry and fraction understanding significantly predicted percentage understanding. Closer inspection indicated that percentage understanding was best predicted by problems sharing similar features, such as fraction word problems and fraction/natural number multiplication/division problems. Our findings suggest that practitioners and software developers may consider revising specific subtopics which share features with percentage problems for students struggling with percentages. More broadly, our study demonstrates how evaluating interdependencies between subtopics covered within an ITS as a data-driven approach can provide practical insights for improving the design of ITSs
Effects of multimodal rheumatologic complex treatment in childhood and adolescence
No full textBackground: The aim of this study was to investigate the effects of multimodal rheumatologic complex treatment (MRCT) in childhood and adolescence. MRCT means a high-frequency treatment program of at least 11 h per week. Methods: MRCTs in children, carried out between May 2009 and May 2022 at the Department of Pediatrics of the University Hospital in Halle (Saale), were included in this study. The effects of the MRCT were evaluated based on inflammatory activity, functionality (using the Childhood Health Assessment Questionnaire (CHAQ)), subjective statements regarding pain intensity, state of health, and coping with the illness, as well as the objective determination of joint mobility. Data were analyzed retrospectively using t-tests to compare different groups and values before and after treatment. Results: During the study period, N = 133 MRCTs were conducted in n = 95 children. The most common diagnosis was juvenile idiopathic arthritis (83.2%). The c-reactive protein (CRP) fell from an average of 25.3 mg/L to 7.3 mg/L, and the erythrocyte sedimentation rate (ESR) fell from 29.5 mm in the first hour to 17.9 mm. Pain intensity was reduced from 5.4 to 4.0. The state of health and coping with the illness also improved. The disability index showed a moderate reduction from 0.92 to 0.81. Furthermore, an improvement in joint mobility was observed. Positive effects were also shown in patients with somatoform disorders. Conclusions: Due to the positive effects of MRCT on subjective well-being and physical health, the treatment program can be recommended for affected children, including patients with an additional diagnosed somatoform disorder
Factors associated with a healthy diet and willingness to change dietary behavior in older adults at increased risk of dementia
No full textBackground: Healthy dietary patterns have been linked to reduced risks for cardiovascular diseases and dementia, making
nutrition an essential part of a comprehensive approach for dementia prevention. Knowledge about factors associated
with a healthy diet in people with increased dementia risk is scarce.
Objective: To analyze dietary habits and associated factors in older adults with increased dementia risk in Germany.
Methods: We used baseline-data of the AgeWell.de-trial (n =1001, %female =52.2, Mage =69.0, SD=4.9). Nutrition was
assessed using a composite score, comprising 11 components covered by national recommendations for a healthy diet
(range =0–11 points). Linear regressions assessed associations of sociodemographic, social, health-related and psychological
factors with consumption of a healthy diet. Further, we assessed stages of change based on the transtheoretical
model of behavior change.
Results: Consumption of a healthy diet was moderate (Median =4, IQR=2). Female sex (b =0.64, 95% CI: 0.41, 0.88),
higher levels of motivation for healthy eating (b =0.22, 95% CI: 0.10, 0.34) and higher self-efficacy (b =0.33, 95% CI: 0.20,
0.46) were linked to a healthy diet. Regarding the stages of behavior change, the majority were in the maintenance stage
(45.2%), followed by the contemplation (21.5%) and precontemplation (21.2%) stages.
Conclusions: Results suggest room for improvement regarding a healthy diet in our sample. Lifestyle-based interventions
in older adults should be tailored towards current levels of motivation and self-efficacy of participants. Including
modules targeting motivation and self-efficacy might help maximize intervention effectiveness
Traditional water structures in villages support amphibian populations within a protected landscape
No full textAmphibians are among the most globally threatened vertebrates, with habitat loss and degradation being the primary drivers of their decline. While natural waterbodies are essential for amphibian survival, artificial habitats can also serve as important refuges, particularly in human-altered landscapes. This study investigates the role of artificial waterbodies in supporting amphibian populations within villages and disturbed areas of Peneda-Gerês National Park (PNPG), a protected area in northern Portugal. We surveyed 162 waterbodies, 68 artificial (tanks, drains, fountains, and cave-like structures) and 94 natural (ponds, streams, stream pockets, and caves) sites within human-altered areas to assess community composition, species richness, Shannon diversity, relative abundance, proportion of occupied sites, and breeding activity. We recorded 10 amphibian species, with species composition showing moderate overlap between the two habitat types, indicating both shared and distinct species assemblages. Natural waterbodies had higher observed species richness (nine species) than artificial sites (seven species). Shannon diversity was greater in natural waterbodies for adults, while juvenile/larvae diversity was greater in artificial habitats. Rana iberica was the most widespread species, found across all waterbody types but predominantly in natural sites. Salamandra salamandra juveniles/larvae were also primarily found and bred in natural habitats, especially stream pockets. In contrast, Lissotriton boscai and Triturus marmoratus were more commonly found and bred in artificial waterbodies, particularly historic water tanks. Natural waterbodies had a higher proportion of their sites occupied (76.6%) compared to artificial ones (51.5%), with stream pockets having the highest at 96.6% and other natural sites around two-thirds. Among artificial sites, tanks were highest with 62.5% occupied. Breeding occurred in one-fifth of surveyed sites, with breeding events recorded in half of stream pockets and over a quarter of tanks. Tanks supported the highest number of breeding species (four of five), compared to three in natural habitats. These findings highlight the importance of water tanks, traditionally used for laundry and water storage, in supporting amphibians in PNPG. They underscore the need to conserve both natural and artificial habitats to protect amphibian biodiversity, especially in human-altered landscapes where artificial waterbodies provide crucial refuges as climate change reduces natural breeding sites