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A multivariate decomposition analysis of drivers of overweight and obesity among Ghanaian women
Get PDFBackgroundOverweight and obesity are rising globally, with Ghana experiencing significant increases among women over the past two decades, raising public health concerns. This study aimed to identify and quantify the key drivers of overweight and obesity among women of reproductive age in Ghana, analysing how these factors have contributed to prevalence changes over time.MethodsData from the 2003, 2008, 2014, and 2022 Ghana Demographic and Health Surveys were analysed using binary logistic regression to assess associations with factors such as age, wealth, and education. Multivariate decomposition analysis quantified the contributions of these factors to the observed increases in overweight and obesity prevalence over time.ResultsHere we show overweight and obesity among Ghanaian women rise significantly, reaching 43% in 2022. Key drivers of change in overweight and obesity include wealth, education, urban residence, age, and region. Women in the wealthiest quintile have three times the odds of overweight (aOR: 3.07 [2.02-4.67]) and over six times the odds of obesity (aOR: 6.73 [3.80-11.91]) compared to the poorest quintile. Decomposition analysis shows that 22.5% of the increase in prevalence was due to changes in population characteristics, such as marital and educational status.ConclusionsOur findings reveal that socio-demographic changes in society, beyond individual behavioural factors, drive the rising overweight and obesity prevalence among Ghanaian women of childbearing age. These findings highlight the dynamic factors influencing weight outcomes and the need for tailored strategies addressing the diverse and evolving determinants of overweight and obesity in Ghanaian women
Cubatures on Wiener space, spatial coalescents, and repulsion-diffusion equations
Get PDFStochastic models are indispensable in the sciences, but simplifying assumptions are often necessary to retain mathematical or computational tractability. In many cases, this leads to models that are only selectively applicable or exhibit unrealistic behaviour. The guiding philosophy of this thesis is to make an attempt at closing this gap, in two ways: Firstly, by making generic simulation algorithms more efficient, which enables the use of more realistic models that would otherwise be computationally infeasible, across different application areas (Chapter I). And secondly, by building and analysing more realistic generalisations of two common models in the particular field of population biology (Chapters II and III)
Rainfall timing and intensity jointly affect the survival and growth of seedling and juvenile Poa crymophila in alpine rangelands on the Qinghai-Tibetan Plateau
Get PDFBackground: Rainfall intensity and timing may affect plant survival and growth differently across life stages. However, there is still a lack of studies that simultaneously examine these combined effects on plant performance, which largely limits our understanding of plant responses to climate change. Methods: Here, we examined the impacts of rainfall intensity (−75%, −50%, 0%, +50% and +75%) and rainfall timing (early growing season: June–July; late growing season: August–September) on the survival and growth of seedling and juvenile Poa crymophila Keng, which is a dominant grass and serves as an important forage for livestock on the alpine rangelands of Qinghai-Tibetan Plateau. Results: Rainfall intensity, timing, and plant life stage jointly affected the survival, growth, and biomass allocation of P. crymophila. Survival and growth increased with increasing rainfall, peaking under +50% rainfall for seedlings and under +75% rainfall for juveniles. Early-season rainfall promoted survival and growth far more than late-season rainfall, while early drought was more detrimental. Seedlings were more vulnerable to drought than juveniles but showed greater flexibility in biomass allocation. Conclusions: Our study provides new insights into how rainfall timing and intensity interact with plant life stage to jointly affect plant survival and growth. Our results underscore the importance of management measures to mitigate the detrimental effects of early-season drought during the seedling stage
Disorder-specific alterations of transient oscillatory dynamics during sleep across cortical and subcortical networks
Get PDFTransient sleep oscillations reflect the dynamic coordination of cortical and subcortical circuits, modulated by slow oscillatory activity. However, the disorder-specific signatures of these events across neurological, pain, and sleep disorders remain poorly characterized. In this exploratory study, we analyzed transient oscillatory dynamics in 99 individuals, including healthy controls and patients with narcolepsy type 1, non-REM parasomnia, idiopathic REM sleep behavior disorder, and fibromyalgia syndrome. Using slow oscillatory referenced time-frequency peak histograms, we applied principal and independent component analysis to uncover spectral and phase-coupling patterns across non-REM and REM stages. We identified reproducible, trait-like oscillatory structures in controls and disorder-specific deviations in patient groups, particularly during NREM sleep. Specifically, patients with narcolepsy type 1 and non-REM parasomnia exhibited altered fast sigma coupling and phase dispersion, while idiopathic REM sleep behavior disorder patients showed reduced fast sigma density and diminished phase synchrony, despite retention of spindle-like spectral structure. In internal cross-validation, slow oscillatory-power features supported robust group-level discrimination in select EEG derivations; however, broader validation in independent samples is required. These findings highlight distinctive, stage-specific microstructural alterations in sleep and pain pathologies and support the future potential of time-frequency peak analysis as a non-invasive tool for phenotyping thalamocortical and subcortical circuit function
Collective transitions from orbiting to matrix invasion in 3D multicellular spheroids
Get PDFCoordinated cell rotation along a curved matrix interface can sculpt epithelial tissues into spherical morphologies. Subsequently, radially-oriented invasion of multicellular strands or branches can occur by local remodeling of the confining matrix. These symmetry-breaking transitions emerge from the dynamic reciprocity between cells and matrix, but remain poorly understood. Here, we show that epithelial cell spheroids collectively transition from circumferential orbiting to radial invasion via bi-directional interactions with the surrounding matrix curvature. Initially, spheroids exhibit an ellipsoidal shape but become rounded as orbiting occurs. However, cells gradually reorient from coordinated rotation towards outward strand invasion due to the accumulation of contractile tractions at discrete sites. Remarkably, the initial ellipsoid morphology predicts subsequent invasion of 2-4 strands roughly aligned with the major axis. We then perturb collective migration using osmotic pressure, showing that orbiting can be arrested and invasion can be reversed. We also investigate coordinated orbiting in "mosaic" spheroids, showing a small fraction of "leader" cells with weakened cell-cell adhesions can impede collective orbiting but still invade into the matrix. Finally, we establish a minimal self-propelled particle model to elucidate how collective orbiting is mediated by the crosstalk of cell-cell and cell-matrix adhesion along a curved boundary. Altogether, this work elucidates how tissue morphogenesis is governed by the interplay of collective behaviors and the local curvature of the cell-matrix, with relevance for embryonic development and tumor progression
Global gridded dataset of heating and cooling degree days under climate change scenarios
Get PDFAccurate projections of heating and cooling demands are crucial for advancing towards the sustainable development goals. Here we present a global dataset of heating degree days (HDDs) and cooling degree days (CDDs) for 3 levels of global mean temperature rise above pre-industrial conditions—1.0 °C (2006–2016), 1.5 °C and 2.0 °C—regardless of the pathways leading to these warming scenarios. The dataset comprises 30 gridded maps (0.883° × 0.556° resolution) characterizing climate variability through 5 statistical metrics per variable and scenario over a representative 10-year period. The dataset reveals a widespread decline in HDDs and a pronounced, nonlinear increase in CDDs, with the most significant shifts in climate intensity and adaptation needs emerging early in the warming trajectory. Furthermore, using the ‘middle-of-the-road’ Shared Socioeconomic Pathway 2-4.5 as a reference, the dataset indicates that the population experiencing extreme heat conditions (exceeding 3,000 CDDs) is projected to nearly double if the 2.0 °C threshold is reached, increasing from 23% (1.54 billion people) in 2010 to 41% (3.79 billion) by 2050, with the largest projected populations affected in India, Nigeria, Indonesia, Bangladesh, Pakistan and the Philippines. This HDD–CDD dataset provides a robust foundation for integrating climate information into sustainability planning and development policy
Probing the Influence of Paternal Diet on Offspring Neuroanatomy With Mouse MRI
Get PDFPurpose: Previous studies have established that parental consumption of a diet high in fat and simple sugar (HF/HSS) leads to long‐term effects on offspring brain development. However, most studies have focused on the effects of maternal diets or the combined effects of both parents’ diets. As literature suggests that fathers’ environmental factors can also impact offspring brain development, we aimed to explore the impact of isolated paternal consumption of an HF/HSS diet on offspring brain structure. Methods: C57Bl/6J male mice were acclimated to an HF/HSS diet for eight weeks prior to mating with females who consumed standard chow (control diet, CD). A matching paternal control group was fed the CD during the acclimation period. Throughout gestation and lactation all dams and offspring were fed the CD; all pups were weaned at postnatal day 21 (P21) and stayed on the CD. At P42 offspring brains were prepared for ex vivo magnetic resonance imaging (MRI). Brain MR images were then segmented for volumetric structural analysis. Results: HF/HSS‐fed sires gained more weight during acclimation than CD sires (p < 0.001). However, offspring weights at weaning (P21) and at endpoint (P42) were not significantly affected by paternal diet. Offspring brain morphology, as assessed by volume measurements of 185 brain structures, was not significantly affected by sire HF/HSS diet alone. Conclusion: While small structural changes cannot be ruled out, the results suggest that previously observed changes in offspring brain structure attributed to parental consumption of HF/HSS diet (selected to mimic some aspects of the human “Western Diet”) require maternal consumption
Interaction and functional specialization across a distributed neural circuit for flexible task control in macaques
Get PDFReversal tasks have been regarded as probes of behavioural inhibition and linked to prefrontal and specifically orbitofrontal cortex. The centrality of behavioural inhibition to reversal task performance and the task’s dependence on particular prefrontal sub-regions have, however, been questioned in primates. Using a combination of whole brain recording, transient ultrasonic disruption, two types of reversal task, and a task model emphasizing identification of transitions between latent states, we show that male macaques track latent state transitions in addition to choice values in reversal tasks. Activity reflecting both these features is prominent in dorsomedial frontal cortex, and anterior and dorsomedial thalamus when, and just before, animals select choices. By contrast, hippocampal activity continually tracks the probability of a reversal between latent states. We identify patterns of activity interaction spanning the three nodes of this circuit and demonstrate that disruption of each leads to reversal task impairment albeit in different ways