Swedish e-Science Research Centre

Abstract. We present a fully implicit finite element method for viscous free surface Stokes problems which are common in glaciology and geodynamics. Standard fully implicit iterative solvers diverge for such problems when using large time steps. We address this by incorporating a stabilization term that vanishes upon convergence. This approach enables the use of large time steps, thereby significantly improving the efficiency of simulations. Furthermore, we leverage the fully implicit solver to develop second-order time-stepping schemes that mitigate the high errors associated with first-order methods for large time steps. The methods are tested and evaluated on model domains relevant to geodynamics and glaciology.

Our aim was to study whether hospitalizations due to high alcohol consumption, as an objective indicator of high alcohol consumption, is associated with hip fractures in non-elderly adults. The participants in this study consist of 10,043 men and women in a survey study in Stockholm 1969-70, when they were 18–25 years old. We used data on hospitalization events due to a hip fracture or a diagnosis indicating high alcohol consumption from 1970 to 2016 acquired from the National Patient Register. This allowed 47 years of follow-up, until the participants were 65–72 years old, an age-span that can be described as “non-elderly adults”. A Cox regression model was used to estimate the hazard ratio (HR) of hip fractures, comparing individuals with and without a diagnosis indicating high alcohol consumption, treating this exposure as a time-varying covariate. There were 151 participants with at least one hip fracture, 86 women and 65 men. There were 450 participants, 173 women and 277 men, who had an alcohol related event, as an indication of alcohol abuse, during the follow-up time of which 24 (10 women and 14 men) also experienced a hip fracture. We found an elevated HR for hip fractures for non-elderly women (HR = 4.59, 95% CI = 2.12–9.95, p < 0.001) and men (HR = 7.65, 95% CI = 4.07–14.36, p < 0.001) with a previous hospitalization-diagnosis indicating high alcohol consumption.

Working memory (WM) is essential for almost every cognitive task. The neural and synaptic mechanisms supporting the rapid encoding and maintenance of memories in diverse tasks are the subject of an ongoing debate. The traditional view of WM as stationary persistent firing of selective neuronal populations has given room to newer ideas regarding mechanisms that support a more dynamic maintenance of multiple items. Various computational WM models based on different biologically plausible plasticity mechanisms have been proposed. We show that these proposed short-term plasticity mechanisms may not necessarily be competing explanations but instead yield interesting interactions that broaden the functional range of models on a wide set of WM task motifs and simultaneously enhance the biological plausibility of spiking neural network models, in particular of the underlying synaptic plasticity. Although reductionist models (WM function explained by one particular mechanism) are theoretically appealing and have increased our understanding of specific mechanisms, they are narrow explanations. In this study, we evaluate the interactions between three commonly proposed classes of plasticity, namely, intrinsic excitability, synaptic facilitation/augmentation, and Hebbian plasticity. We systematically test combinations of mechanisms in a spiking neural network model on a broad suite of tasks or functional motifs deemed principally important for WM operation, such as one-shot encoding, free and cued recall, and multi-item delay maintenance and updating. Our analysis of the operational task performance indicates that a composite model is superior to more reductionist variants. Importantly, we attribute the observable differences to the principle nature of specific types of plasticity.

<strong class="journal-contentHeaderColor">Abstract.</strong> We present a fully implicit finite element method for viscous free surface Stokes problems which are common in glaciology and geodynamics. Standard fully implicit iterative solvers diverge for such problems when using large time steps. We address this by incorporating a stabilization term that vanishes upon convergence. This approach enables the use of large time steps, thereby significantly improving the efficiency of simulations. Furthermore, we leverage the fully implicit solver to develop second-order time-stepping schemes that mitigate the high errors associated with first-order methods for large time steps. The methods are tested and evaluated on model domains relevant to geodynamics and glaciology.

Drylands account for a disproportionate share of the world’s armed conflicts, a pattern frequently interpreted through the lens of resource scarcity – where climate change and water stress are seen as primary drivers of violence. While this framing underscores critical environmental pressures, it risks simplifying the complex social, ecological and political realities of these regions. This article critically examines the climate-conflict narrative surrounding Syria, which posits that drought-induced agricultural collapse and rural outmigration significantly contributed to the onset of civil war. Building on this critique, the paper advocates for a broader conceptual shift – viewing drylands not solely as zones of vulnerability, but as landscapes of endurance. In these regions, communities often navigate both extreme climatic conditions and chronic insecurity, which together constrain agricultural productivity and perpetuate poverty. This perspective highlights the adaptive capacities of dryland populations and the lessons they offer for understanding survival under compound stress. It also challenges dominant narratives and opens space for interdisciplinary approaches that integrate quantitative and qualitative perspectives. The article calls for a more nuanced research agenda that centers lived experience, long-term adaptation and the interplay between environmental and political pressures.

Young males with forced migration experiences (YMFMEs) face numerous health challenges, particularly in terms of sexual and mental health. The disparity in health beliefs and knowledge between healthcare providers (HCPs) and vulnerable groups can exacerbate these challenges. Sexual health encompasses both physical and psychosocial aspects; however, the interplay between these two aspects is often overlooked in research and clinical practice. Additionally, existing research has focused predominantly on females, neglecting the specific needs of YMFMEs. Engaging HCPs provides expert insights into the unique healthcare challenges faced by YMFMEs, enabling the development of tailored, evidence-based interventions that address their specific needs. A patient-centered framework was used to support the interpretation of the data. This study aims to explore HCPs’ perceptions of the sexual and mental health needs of YMFMEs and their perspectives on approaches to addressing these needs in the Stockholm Region, Sweden. This qualitative study was conducted in the Stockholm Region, Sweden, between May and June 2021 using semi-structured interviews. Nine health care providers were included in the study. The interview transcripts were analyzed using inductive content analysis. We identified three themes that describe HCPs’ perceptions of YMFMEs’ sexual and mental health needs in healthcare; (1) recognizing and incorporating the biopsychosocial interconnectedness of sexual and mental health into healthcare practices; (2) addressing gaps in health literacy, cultural norms, and expectations is crucial for fostering trust and promoting patient-centered care; and (3) the impact of forced migration and discrimination on YMFMEs’ mental and sexual health and the need for targeted knowledge in healthcare practices. This study highlights the importance of HCPs understanding the complex relationship between forced migration, mental health, and sexual health for YMFMEs and integrating this awareness into healthcare practices.

<strong class="journal-contentHeaderColor">Abstract.</strong> The efficient and accurate simulation of grounding line dynamics in marine ice-sheet models remains a challenge, largely due to restrictive time-step limitations. The restrictive time step size of ice-sheet simulations (&sim; ∆<em>t</em> = 0.01&minus;0.5 years) has led to the routine use of approximate models that compromise physical complexity compared to full Stokes models. To address the time-step restriction and enhance the applicability of full Stokes simulations, we implement a numerical stabilisation scheme at the ice-ocean interface, namely the Free-Surface Stabilisation Algorithm (FSSA). The FSSA acts by predicting the surface elevation at the next time step, resulting in a reduction in surface oscillations and an increase in the largest numerically stable time step. When applied to the ice-ocean interface, FSSA acts in combination with the <em>sea spring</em> numerical stabilisation scheme, allowing larger time steps to be taken. In order to test the capabilities of the FSSA when applied to the ice-ocean interface, we perform the benchmark simulation of Experiment 3a from the Marine Ice Sheet Model Intercomparison Project (MISMIP). These simulations demonstrate the ability of the model to capture grounding line migration on both prograde slopes (oceanward sloping) and retrograde slopes (inland sloping). We find a time step size of ∆<em>t</em> = 10 years to be numerically stable and accurate in the MISMIP experiment, which is more than an order of magnitude larger than the small time steps traditionally used. In comparison, a time-step size of ∆<em>t</em> = 50 years can maintain numerical stability, but is not capable of capturing the full range of grounding-line motion in the MISMIP experiments. We further demonstrate the applicability of the FSSA to a 3D marine terminating model domain, finding that a time-step size of ∆<em>t</em> = 10 years is numerically stable. The increase in the largest numerically stable time step by greater than an order of magnitude in marine-terminating Stokes ice-flow problems through the inclusion of FSSA broadens the applicability of Stokes models, which have otherwise been deemed too computationally expensive for large-scale applications.

Drylands account for a disproportionate share of the world’s armed conflicts, a pattern frequently interpreted through the lens of resource scarcity – where climate change and water stress are seen as primary drivers of violence. While this framing underscores critical environmental pressures, it risks simplifying the complex social, ecological and political realities of these regions. This article critically examines the climate-conflict narrative surrounding Syria, which posits that drought-induced agricultural collapse and rural outmigration significantly contributed to the onset of civil war. Building on this critique, the paper advocates for a broader conceptual shift – viewing drylands not solely as zones of vulnerability, but as landscapes of endurance. In these regions, communities often navigate both extreme climatic conditions and chronic insecurity, which together constrain agricultural productivity and perpetuate poverty. This perspective highlights the adaptive capacities of dryland populations and the lessons they offer for understanding survival under compound stress. It also challenges dominant narratives and opens space for interdisciplinary approaches that integrate quantitative and qualitative perspectives. The article calls for a more nuanced research agenda that centers lived experience, long-term adaptation and the interplay between environmental and political pressures.

We investigated the element-specific electronic structure and charge-carrier dynamics of a single-crystal ferromagnet <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>CoS</a:mi><a:mn>2</a:mn></a:msub></a:math> with complementary x-ray spectroscopy techniques. Hard x-ray photoemission (HAXPES) is used to provide crucial information on the bulk electronic structure and chemical bonding in <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msub><b:mi>CoS</b:mi><b:mn>2</b:mn></b:msub></b:math> that is compared against the isoelectronic paramagnet <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:msub><c:mi>CoSe</c:mi><c:mn>2</c:mn></c:msub></c:math>. The Co <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:mn>1</d:mn><d:mi>s</d:mi></d:mrow></d:math> core-level line shows several satellite features for <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:msub><e:mi>CoS</e:mi><e:mn>2</e:mn></e:msub></e:math>, showing explicit charge-transfer processes and local screening of the core hole by S ligands, whereas no such features are observed in <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:msub><f:mi>CoSe</f:mi><f:mn>2</f:mn></f:msub></f:math>. The satellite structures indicate the electronic configuration of divalent <g:math xmlns:g="http://www.w3.org/1998/Math/MathML"><g:msup><g:mrow><g:mi>Co</g:mi></g:mrow><g:mrow><g:mn>2</g:mn><g:mo>+</g:mo></g:mrow></g:msup></g:math> as a combination of <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:mrow><h:msup><h:mi>d</h:mi><h:mn>8</h:mn></h:msup><h:mi mathvariant="normal">Ḻ</h:mi></h:mrow></h:math> and <j:math xmlns:j="http://www.w3.org/1998/Math/MathML"><j:mrow><j:msup><j:mi>d</j:mi><j:mn>9</j:mn></j:msup><j:msup><j:mi mathvariant="normal">Ḻ</j:mi><j:mn>2</j:mn></j:msup></j:mrow></j:math> in addition to the nominal ionic <l:math xmlns:l="http://www.w3.org/1998/Math/MathML"><l:msup><l:mrow><l:mi>d</l:mi></l:mrow><l:mn>7</l:mn></l:msup></l:math> state, where <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"><m:mi mathvariant="normal">Ḻ</m:mi></m:math> represents an S <o:math xmlns:o="http://www.w3.org/1998/Math/MathML"><o:mrow><o:mn>3</o:mn><o:mi>p</o:mi></o:mrow></o:math> hole. We employ resonant Auger spectroscopy across the S <p:math xmlns:p="http://www.w3.org/1998/Math/MathML"><p:mi>K</p:mi></p:math>-edge for <q:math xmlns:q="http://www.w3.org/1998/Math/MathML"><q:msub><q:mi>CoS</q:mi><q:mn>2</q:mn></q:msub></q:math> to obtain electron delocalization times to adjacent Co atomic sites. The fast carrier dynamics are attributed to strongly screened Coulomb interactions and hence a facile carrier delocalization. The strong hybridization formed between the Co <r:math xmlns:r="http://www.w3.org/1998/Math/MathML"><r:mrow><r:mn>3</r:mn><r:mi>d</r:mi></r:mrow></r:math> and S <s:math xmlns:s="http://www.w3.org/1998/Math/MathML"><s:mrow><s:mn>3</s:mn><s:mi>p</s:mi></s:mrow></s:math> states with pronounced charge-transfer character reflects a self-doped system with a finite density <t:math xmlns:t="http://www.w3.org/1998/Math/MathML"><t:mi>n</t:mi></t:math> of holes at the sulfur site (<u:math xmlns:u="http://www.w3.org/1998/Math/MathML"><u:msup><u:mi mathvariant="normal">Ḻ</u:mi><u:mi>n</u:mi></u:msup></u:math>), in line with recent models that indicate a negative charge-transfer energy for <w:math xmlns:w="http://www.w3.org/1998/Math/MathML"><w:msub><w:mi>CoS</w:mi><w:mn>2</w:mn></w:msub></w:math>. In addition to HAXPES data, we also report on experimental and theoretical <x:math xmlns:x="http://www.w3.org/1998/Math/MathML"><x:mi>L</x:mi></x:math>-edge x-ray absorption and x-ray magnetic circular dichroism data for <y:math xmlns:y="http://www.w3.org/1998/Math/MathML"><y:msub><y:mi>CoS</y:mi><y:mn>2</y:mn></y:msub></y:math> that demonstrate multiconfiguration effects in the excitation process. To enable a direct comparison of the experimental spectra, we used density functional theory calculations to obtain the projected density of states to describe the ground-state electronic structure. The existence of fast carrier dynamics and strong charge-transfer properties, demonstrated in this study, highlights the unique nature of <z:math xmlns:z="http://www.w3.org/1998/Math/MathML"><z:msub><z:mi>CoS</z:mi><z:mn>2</z:mn></z:msub></z:math> with a wide potential in topological spintronics applications and integration in energy-related device platforms.

Abstract. We present a fully implicit finite element method for viscous free surface Stokes problems which are common in glaciology and geodynamics. Standard fully implicit iterative solvers diverge for such problems when using large time steps. We address this by incorporating a stabilization term that vanishes upon convergence. This approach enables the use of large time steps, thereby significantly improving the efficiency of simulations. Furthermore, we leverage the fully implicit solver to develop second-order time-stepping schemes that mitigate the high errors associated with first-order methods for large time steps. The methods are tested and evaluated on model domains relevant to geodynamics and glaciology.