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In this article, we apply the Bestvina–Mess type formula for relatively hyperbolic groups, which is established by Tomohiro Fukaya, to automorphism groups of K3 surfaces, and we show that the virtual cohomological dimension of automorphism groups of K3 surfaces is determined by the covering dimension of the blown-up boundaries associated with their ample cones.
Traumatic and stressful life events can have lasting effects on mental health, particularly among older adults in low-resource settings. In Latin America, there is limited qualitative evidence capturing the lived experiences of these events. This study explores how older adults in Peru reflect on traumatic and stressful events throughout their lives, and how these experiences continue to shape their mental health in later life. This qualitative study was nested within the Global Excellence in COPD Outcomes (GECo) study in Lima, Peru. We conducted semi-structured, narrative-based interviews with 38 older adults (≥60 years) with moderate to severe symptoms of depression (Patient Health Questionnaire-9 ≥ 10), anxiety (Beck Anxiety Inventory ≥ 16) or a history of mental health treatment. Four main categories emerged: (1) violence (emotional, physical or sexual), (2) abandonment or loss of close relatives, (3) onset of severe illness or disability and (4) other miscellaneous life disruptions. Participants described their memories of past stressful events as deeply embedded in current thoughts and, in some cases, as shaping how they experience certain emotions in the present. Addressing trauma in older adults may improve well-being in low-resource settings. Recognizing the enduring impact of life-course stressors is crucial for culturally sensitive mental health interventions.
Healthcare systems worldwide are under pressure due to increasing demand and rising costs. Simultaneously, there is a shortage of healthcare workers. This is leading to increased pressure on primary care, especially in countries where general practitioners (GPs) perform a gatekeeping function. One way to alleviate this pressure on GPs, and to reduce healthcare costs, is to introduce or expand, direct accessibility to allied health professionals. This study investigated the factors associated with this direct accessibility in the Netherlands.
Method:
We used data from electronic health records of physiotherapists, speech therapists, and dietitians, drawn from the 2022 Dutch Nivel Primary Care Database (Nivel’s PCD). The data included information ranging from 15,470 to 776,690 patients, and for 62 to 593 practices, depending on the particular paramedic discipline. Multilevel logistic regressions were employed to identify patient and practice characteristics associated with direct access.
Results:
Patient characteristics significantly associated with direct access included younger age, higher socioeconomic status, and diagnosis. The patient’s sex was also identified as a factor associated with the use of direct access in physiotherapy and dietetics, but not in speech therapy. Moreover, we observed significant variation between practices. We found that the dominant health insurer in an area was sometimes associated with direct access, as well as the number of therapists working in a practice.
Conclusion:
We observed significant associations between patient and practice characteristics and the direct access to allied health professionals in primary care. These findings suggest that the use of direct access to allied health professionals could be increased in order to enhance healthcare efficiency and thereby relieve pressure on GP care.
Evidence Synthesis has seen an enormous increase recently, across many different scientific disciplines. Despite its popularity, it has also been the subject of significant criticism. One of the main critiques of evidence synthesis, is the existence and treatment of heterogeneity between primary studies. The aim of this paper is to re-examine heterogeneity in evidence synthesis, including perspectives from evolutionary biology, ecology and conservation. I argue that while some of the critiques of heterogeneity remain valid, there are contexts where it is much less problematic. Furthermore, I propose that heterogeneity can be useful, as analysing it can provide valuable information.
Protecting animals from anthropogenic influences is important in vulnerable ecosystems such as Antarctica. A potential recent activity affecting Antarctic wildlife is the use of unmanned aerial vehicles (UAVs). Previous studies in this area have mainly focused on animal behavioural observations and have reported reactions to UAVs in many cases. To gain insights into the influence of UAVs on physiology (stress hormones) in addition to behavioural reactions, we conducted an experiment on chinstrap penguin chicks (Pygoscelis antarcticus) on the South Shetland Islands (Antarctica) during the breeding season of 2017–2018. Using a small quadcopter UAV, we performed flights over groups of penguin chicks in the early crèche phase using ‘Hard’ and ‘Soft’ treatment setups (15 and 50 m above the penguins, respectively). The behavioural observations revealed clear reactions to the UAV during the Hard treatment, but we could not find an association between such UAV activity and stress hormone levels. As we cannot clearly disentangle the effects of handling during blood sampling and the direct influence of the UAV, we conclude that the physiological impact of overflights at 15 m ranges from no impact to a maximum impact equal to the impact associated with animal handling. During the Soft treatment (UAV overflights at 50 m), no behavioural or physiological effects were detected.
Understanding the interplay between buoyancy and fluid motions within stably stratified shear layers is crucial for unravelling the contribution of flow structures to turbulent mixing. In this study, we examine statistically the local relationship between stratification and fluid deformation rate in wave and turbulent regimes, using experimental datasets obtained from a stratified inclined duct (SID) containing fluids of different densities that form an exchange flow. We introduce rotational and shear components of varying strength within the vorticity and a family of coherent gradient Richardson numbers ($Ri_C$), ratios related to the buoyancy frequency and the strength of either the rotational or shearing motion. Conditional statistical analysis reveals that both shear and stratification intensity affect the probability distribution of the $Ri_C$, with extreme events occurring more frequently in areas of weak stratification. In the wave regime, we identify the persistence of fast-spin vortices within the strongly stratified density interface. However, scouring of the density interface is primarily driven by shearing motions, with baroclinic torque making a notable contribution to enstrophy transport. In the turbulent regime, rigid-body rotations occur at significantly shorter time scales than that associated with the local buoyancy frequency, making them more disruptive to stratification than shear. Additionally, correlation analysis reveals that irrotational strain distorts stable stratification similarly to shearing motions, but is weaker than both shearing and rotational motions and less likely to have a time scale longer than that related to the buoyancy frequency. Moreover, we observed that the interplay between rotational and shearing motions intensifies as stratification increases. Finally, a comparison of length scales along the shear layers highlights the $Ri_C$ as a valuable measure of the relative sizes of different motions compared with the Ozmidov scale and shows that stratification can influence sub-Ozmidov scales through baroclinic torque. This study highlights the critical impact of the type, strength and location of fluid deformations on localised mixing, providing new insights into the role of rotational motions in shear-driven stratified flows.
Water resources from the Indus Basin sustain over 270 million people. However, water security in this region is threatened by climate change. This is especially the case for the upper Indus Basin, where most frozen water reserves are expected to decrease significantly by the end of the century, leaving rainfall as the main driver of river flow. However, future precipitation estimates from global climate models differ greatly for this region. To address this uncertainty, this paper explores the feasibility of using probabilistic machine learning to map large-scale circulation fields, better represented by global climate models, to local precipitation over the upper Indus Basin. More specifically, Gaussian processes are trained to predict monthly ERA5 precipitation data over a 15-year horizon. This paper also explores different Gaussian process model designs, including a non-stationary covariance function to learn complex spatial relationships in the data. Going forward, this approach could be used to make more accurate predictions from global climate model outputs and better assess the probability of future precipitation extremes.
Supply chain management is a substantially complex area for many businesses due to its diverse set of actions, agents, decisions, risks, and uncertainties. Consequently, supply chains often break up in disarray due to their structural complexity coupled with risks and uncertainties in the absence of clear objectives. Işık Biçer addresses these issues by uncovering the fundamental trade-offs of supply chain management, their economic causes, and strategic implications. He offers a novel framework of supply chain management based on its role in economic systems. The framework shows four effective supply chain strategies according to business models and organizational sensitivity to operational trade-offs. Furthermore, it offers a detailed account of the digital transformation of supply chains, elaborating on crucial aspects of the design and implementation of digitalization. This is an indispensable source for supply chain professionals, consultants, economists, and policymakers with a keen interest in supply chain management.
Intellectual conflict between Early Christians and pagans was not uncommon during the first centuries of the Christian era, as is amply reflected in writings from this period. In this study, Brad Boswell deepens our understanding of the nature and aims of such conflict through a study of two key texts: Against the Galileans, by Roman Emperor Julian 'the Apostate,' and Against Julian, by bishop Cyril of Alexandria written nearly a century later. Drawing from Alasdair MacIntyre's philosophy of conflict between traditions, he explores how both texts were an exercise in 'narrative conflict' whose aim was to demonstrate the superior explanatory power of their respective traditions' narrative. Acknowledging the shared cultural formation between a pagan like Julian and a Christian like Cyril, Boswell challenges interpretive models emphasizing the points of commonality between the traditions. He offers a fresh approach to Julian's anti-Christian writings, provides the foundational analysis of Cyril's little-studied treatise, and invites reconsideration of the emerging Christian tradition within its intellectual contexts.
This Element discusses the central role of models within evolutionary biology, offering an accessible introduction and synthesis of literature in both evolutionary biology and the philosophy of models. We will examine three questions: first, what does it mean to be a 'model' and to engage in 'modelling'? Second, what types of models are employed within evolutionary biology? Third, how can models of evolution be tested? In exploring the answers to these questions, this Element hopes to highlight how evolutionary biology and philosophy of biology can usefully interact to understand conceptual and methodological problems arising from modelling evolution.
This Element examines the arguments advanced by the Tübingen-Milan School in support of the claim that Plato had Unwritten Doctrines (agrapha dogmata), revealed in Aristotle and other testimonia and indicated – but not explicitly treated – in some of his dialogues. The Unwritten Doctrines are primarily concerned with Plato's Theory of Principles of (the One and the Indefinite Dyad) which accounts for unity and multiplicity respectively. This Element considers two opposing approaches to reading Plato: that of sola scriptura (through the writings alone) or via the tradition. While it may appear counter-intuitive to privilege other sources over Plato's own works, his criticism of writing in the Phaedrus and the 'deliberate gaps', where he teases the reader with the possibility of a fuller response than that provided on the current occasion, firmly indicate the existence of doctrines not committed to his dialogues.
Alcohol use disorder (AUD) increases the likelihood of suicide attempts. The characteristics of AUD that increase suicide attempt risk remain unclear.
Aims
To identify factors associated with a history of suicide attempts and with suicidal acts occurring within a 2-year follow-up in patients with AUD.
Method
This multicentre, prospective cohort study included patients with AUD within 1 week of admission to in-patient care for alcohol withdrawal management. Sociodemographic and clinical data were collected during a face-to-face clinician interview at baseline. Follow-up telephone interviews were conducted up to 24 months post-inclusion to assess the primary end-point: the occurrence of a suicidal act (suicide attempt or completed suicide). To identify factors associated with past suicide attempts, Student’s t-tests, chi-squared tests and logistic regression were performed. Univariate survival analyses and a multivariate Cox model were computed to identify predictors of suicidal acts occurring during the follow-up period.
Results
Of the 779 patients included in the study, 337 (43.3%) had a history of suicide attempts. This was significantly associated with a history of major depressive disorder, female gender and higher levels of suicidal ideation and hopelessness. Regarding the prospective analysis, suicidal acts occurred in 90 (11.5%) patients. A history of severe alcohol withdrawal symptoms, defined as delirium tremens or seizures (adjusted hazard ratio (aHR) 2.38, 95% CI 1.38–4.10, P = 0.002), and a history of suicide attempts (aHR 1.84, 95% CI 1.14–2.99, P = 0.013), were associated with higher occurrence of suicidal acts, while living alone (0.47, 95% CI 0.28–0.78, P = 0.004) was a protective factor.
Conclusions
While a history of suicide attempts is a well-established risk factor for future suicidal acts, a history of severe alcohol withdrawal symptoms emerges as an even stronger predictor. Further studies are necessary to generalise this finding and use it to identify patients at higher risk of suicidal acts.
This study from the Accelerator Mass Spectrometry Laboratory at the Center for Physical Sciences and Technology (FTMC), Vilnius, Lithuania, presents a detailed description of the sample preparation methods employed in the laboratory, with a focus on two AMS systems: a single-stage accelerator mass spectrometer (SSAMS) and a low energy accelerator (LEA). A pivotal aspect of this article is our participation in the GIRI intercomparison test, demonstrating our commitment to precision and accuracy in radiocarbon dating, with the average z-score values of the GIRI test being 0.16 ± 1.66 for SSAMS and –0.04 ± 1.52 for LEA. The outcomes from this participation validate the meticulous sample preparation procedures at Vilnius Accelerator Mass Spectrometry Laboratory and offer significant insights into the efficiency and reliability of SSAMS and LEA systems, contributing to a better understanding of their capabilities in radiocarbon analysis.