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Neighborhood social structure in Sweden: A latent transition analysis using registry data from 1991 to 2020
No full textBackground: Neighborhoods shape daily life through physical and social structures, such as socioeconomic conditions, population density, and resident turnover. Decades of research link neighborhood characteristics to health and behavioral outcomes. However, these factors are often studied independently, neglecting their interrelated nature. Methods: Using Swedish population registry data, we employed latent class analyses to identify neighborhood typologies across six timepoints spanning 1991-2020. Neighborhoods, defined by Demographic Statistical Areas, were characterized by socioeconomic conditions, ethnic heterogeneity, residential instability, and urbanicity. Latent transition analyses examined changes over time. Results: Four neighborhood types emerged in the early period (1991-2000): Rural Low-Diversity (45 %), Urban Professional (27 %), Urban Affluent (21 %), and Resource-Limited (7 %). From 2001 onwards, five types were identified, with the addition of Urban High-Diversity (9 %) and Rural Resource-Limited (3 %). Three types, Rural Low-Diversity, Urban Professional, and Urban Affluent, persisted across 30 years, representing 87-93 % of neighborhoods, with over 90 % of neighborhoods retaining their classification over time. Conclusions: This multidimensional framework offers a foundation for future research, urban planning, and policy development.Funding Agencies|Swedish Research Council (Vetenskapsradet) [2021-02105]; Swedish Research Council [2021-02105] Funding Source: Swedish Research Council</p
Associations between healthcare workers' substance use and quality of care : Findings from a one-year Swedish follow-up study
No full textBackground: Problem drinking and illicit drug use among healthcare workers (i.e., physicians and nurses) may impair their attention and cognitive functioning, thereby increasing the risk of medical errors and diminishing the quality of patient care. Objective: To investigate the association between healthcare workers' problem drinking and illicit drug use with subsequent self-rated quality of care provided. Design: A two-wave longitudinal observational study. Methods: Panel data were drawn from the Longitudinal Occupational Health Survey in Healthcare Sweden (LOHHCS), collected in 2022 (baseline) and 2023 (follow-up), encompassing a sample of 3280 healthcare workers. Questionnaires included problem drinking, illicit drug use (cannabis and stimulants), and self-rated quality of care they provide to patients. Logistic regression models analysed relationships between the study variables. Results: At baseline, the prevalence of problem drinking was 3.8 %, and illicit drug use was 1.3 %. Both problem drinking (OR = 1.93, 95 % CI = 1.28–3.02) and illicit drug use (OR = 2.07, 95 % CI = 1.00–4.29) were significantly associated with lower self-rated quality of care provided at follow-up, after adjustment for confounding variables. Conclusions: This novel longitudinal study shows that healthcare workers reporting substance use at baseline were about twice as likely to report providing poor quality of care one year later. These findings are of clinical relevance and highlight the need for targeted preventive measures and interventions to safeguard the health and well-being of healthcare workers while maintaining quality standards in patient care.
Circular economy in the extractive frontier: Tensions and pathways for transformative change in mining
No full textThe mining sector, like other sectors of the economy, is under increasing pressure to adopt circular economy (CE) principles across its value chains and core operations. This paper offers a critical and conceptually grounded contribution to understanding how CE can support systemic transformation in one of the most resource-intensive and path-dependent sectors of the global economy. It examines the structural and institutional conditions that shape the adoption of CE in mining and identifies key tensions that constrain or enable transformative change. In parallel, the paper explores emerging pathways informed by technological innovation, shifts in production routines, and the rise of new circular business models. These insights are synthesised into a multi-level framework that captures the dynamic interactions between micro-, meso-, and macro-level processes shaping CE transitions. In addition to offering a diagnostic perspective, the framework outlines concrete action points for advancing systemic change.QC 20250908</p
Suicide after involuntary psychiatric care : a nationwide cohort study in Sweden
No full textBackground Little is known about the risk of suicide in individuals treated against their will in involuntary psychiatric care (IPC). This population-based study provides a first comprehensive description of suicide among individuals who experienced IPC. Methods We studied all individuals discharged from IPC in Sweden from 2010 through 2020. Clinical and sociodemographic characteristics are reported followed by suicide risk for the complete IPC population and stratified by sex, age, IPC history, and diagnostic category. Crude and adjusted relative risks compared to all individuals discharged from psychiatric in-and outpatient care and the general population were estimated using Poisson regression. Suicide methods, seasonal trends, and geographical variance are also reported. Findings We identified 72 275 patients treated in IPC with a total of 134 514 inpatient care episodes (mean age = 44.8 years, 37 462 [51.8%] males). Of these, 2104 (2.9%) died by suicide over a median follow-up time of 4.4 years (IQR: 1.8-7.5). Suicide decedents were younger, more often male, single, diagnosed with personality and substance use disorders, and had a history of self-harm and IPC, compared to those who did not die by suicide. The absolute risk (crude incidence rate (IR) per 100 000 person-years) for all IPC patients was highest closest to discharge (IR1month = 2941 [2538, 3408]) and decreased thereafter (IR5years = 738 [705, 773]). Suicide risk in IPC patients was elevated relative to psychiatric inpatients (crude IR ratio (IRR)5years = 1.57 [1.48, 1.65]), psychiatric outpatients (IRR5years = 3.77 [3.58, 3.97]), and the general population (IRR5years= 55.52 [52.65, 58.54]). Interpretation We found substantial risk differences in distinct subgroups of IPC patients and an excess suicide risk among IPC patients compared to other clinical populations. These findings warrant further investigation as they could inform clinicians and policy makers regarding potential risk stratification, monitoring, and care. Preventing suicides after IPC should be a priority
Smiling in the East and the West : Anatomical, cultural and sociological considerations in facial reanimation surgery
No full textThe importance of the smile as a means of communicative and metacommunicative signal in social engagement has been known and highlighted in studies dating back to the early 19th century. It remains a cornerstone of reconstructive surgeries for the paralyzed face. This paper calls attention to the differences between the Eastern and Western smile. Anatomical, cultural, and sociological peculiarities inform the way these populations smile and the way smiling itself is perceived. Reconstructive surgery of today would benefit from considering these aspects and allowing them to individualize the goals of reanimation procedures. (c) 2025 Published by Elsevier Ltd on behalf of British Association of Plastic, Reconstructive and Aesthetic Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/
Drivkraft för resiliens : En socioteknisk studie av värdeskapande genom samverkan och för hantering av förändringar inom tjänster för vetenskaplig kommunikation
No full textScholarly communication is a complex socio-technical information system where human actors and evolving digital technologies interact to advance knowledge creation, validation, and the sharing of information. While academic libraries have long been a core component, they have shifted from passive repositories to active service providers within the information system space in response to profound disruptions. The persistent uncertainty facing libraries challenges traditional knowledge creation practices, historically rooted in managing physical artifacts, and presents new opportunities for innovation centered on networked information access and human-focused digital service design. This dissertation investigates the evolving role of scholarly communications services amidst systemic disruptions like the COVID-19 pandemic and the rise of generative AI. The research is understood as both a study of disruption and a study conducted through disruption. The central research question is: How does value co-creation shape scholarly communication as a socio-technical system across diverse contexts and amidst systemic disruptions? Grounded in socio-technical Information Systems theory and using Service-Dominant Logic as its primary analytical framework, this dissertation employs a retrospective metanarrative of engaged scholarship, synthesizing findings from five empirical studies (2018 and 2025). The findings demonstrate an organizational shift from a static content pipeline to a dynamic service platform, where participants are repositioned from passive consumers to active co-creating partners. Value emerges not from a delivered product, but from interactive processes (e.g., participatory design, critical pedagogy) that generate tangible benefits. Results reveal that in an era of perpetual crisis, resilience and relevance are not generated from technology alone, but also from designing and nurturing human-centered co-creation. The dissertation’s primary contribution is an empirically grounded framework for understanding scholarly communication as a value cocreation ecosystem. This approach provides a process-based view, blending the Delone & McLean Information Systems Success model to explicitly incorporate value co-creation, and deepening the socio-technical perspective. Findings yield an actionable recommendation to design for participation, not just access. The research concludes that in an age of artificial intelligence and systemic uncertainty, our most valuable and resilient infrastructure is human connection
Experimental and numerical evaluation of convective heat transfer correlations in a packed bed of iron ore pellets
No full textModeling heat transfer in packed bed processes such as iron ore pelletization is essential for optimizing process operation and furnace design. In these systems, materials like magnetite iron ore undergo thermal and chemical transformations, where heat and mass transfer are often coupled with heat effects from multiple processes — including both exothermic chemical reactions (e.g., oxidation) and endothermic physical changes (e.g., drying and sintering). As the industry moves towards fossil-free ironmaking, it becomes increasingly important to isolate pure heat transfer behavior, independent of chemical reactions, to support the development of sustainable process schemes. This study investigates convective heat transfer in a packed bed by evaluating several established correlations against the conventionally used modified Ranz–Marshall correlation. Pilot pot-scale experiments were performed by isothermally heating 120 kg of already indurated iron ore pellets at 300 °C to avoid chemical reactions, with additional experiments at 500 °C and 700 °C to assess performance at elevated temperatures typical of industrial pelletization. Results show that the modified Ranz–Marshall correlation underpredicts heat transfer rates under conditions isolating convective heat transfer, reinforcing the need for this investigation. The Wakao–Funazkri and Rowe–Claxton correlations provided the best agreement with experimental data, particularly at 300 °C. Minor deviations at higher temperatures suggest the influence of unaccounted variables, warranting further study. Sensitivity analysis identified gas velocity as the most significant parameter affecting heat transfer. The results suggest that adopting the Wakao–Funazkri and Rowe–Claxton correlations can provide a stronger basis for predictive pellet heat transfer modeling in future process design and simulation work.Funding: Swedish Mining Innovation;Fulltext license: CC BY</p
Analysis of RUL dynamics and uncertainty via time transformation
No full textThis work introduces a novel analytical method to analyze the dynamics of remaining useful life (RUL) and quantify uncertainty in its estimation. The approach employs a time transformation that makes the mean residual life (MRL) a linear function of transformed time, enabling the derivation of explicit RUL confidence bounds. Once mapped back to physical space, the bounds quantify aleatoric (stochastic) uncertainty in RUL and yield asymmetrical confidence intervals for both parametric and non-parametric lifetime distributions. The approach leverages a key feature of reliability distributions: the average RUL loss rate, , in transformed time, facilitating a direct derivation of confidence bounds. In parametric cases, is uniquely defined by the reliability distribution parameters, while for non-parametric distributions, it is derived from data by estimating the coefficient of variation. Higher slopes indicate faster degradation, leading to narrower confidence intervals and lower RUL variance. The method’s applicability to stochastic processes and robustness under different data volumes are also investigated and discussed. The novel approach reveals heretofore unknown insights into classical reliability distributions. It is demonstrated through real-world applications, including LED reliability assessment, parallel system RUL estimation, and turbofan lifespan prediction using NASA N-CMAPSS data, offering a new perspective on the evolving dynamics of mean residual life and remaining useful life.Validerad;2025;Nivå 2;2025-10-14 (u4);Full text licens: CC BY</p
Emerging Role of 2D Materials in Photovoltaics: Efficiency Enhancement and Future Perspectives
No full textThe growing global energy demand and worsening climate change highlight the urgent need for clean, efficient and sustainable energy solutions. Among emerging technologies, atomically thin two-dimensional (2D) materials offer unique advantages in photovoltaics due to their tunable optoelectronic properties, high surface area and efficient charge transport capabilities. This review explores recent progress in photovoltaics incorporating 2D materials, focusing on their application as hole and electron transport layers to optimize bandgap alignment, enhance carrier mobility and improve chemical stability. A comprehensive analysis is presented on perovskite solar cells utilizing 2D materials, with a particular focus on strategies to enhance crystallization, passivate defects and improve overall cell efficiency. Additionally, the application of 2D materials in organic solar cells is examined, particularly for reducing recombination losses and enhancing charge extraction through work function modification. Their impact on dye-sensitized solar cells, including catalytic activity and counter electrode performance, is also explored. Finally, the review outlines key challenges, material limitations and performance metrics, offering insight into the future development of next-generation photovoltaic devices encouraged by 2D materials.Validerad;2025;Nivå 2;2025-10-02 (u5);Full text license: CC BYFor funding information, see: https://link.springer.com/article/10.1007/s40820-025-01869-z#Fun</p
Development of 3D printable thermoplastic polymer composites for tribological applications
No full textThe growing interest in environmental sustainability aims to improve resource efficiency and minimize energy consumption throughout material manufacturing, usage, end-of-life handling, and recycling aspect. Energy loss due to friction and wear of materials is the major challenge in machine components. Therefore, reducing friction and improving wear resistance with an appropriate selection of surface materials is the most direct route to reducing energy loss via reduced frictional forces, which contributes directly to sustainable development in the field of tribology and machine components. In that regard, polymer-based materials (PBM) are widely used as load-carrying components, such as bearings in tribological applications. In recent years, additive manufacturing (AM), also known as 3D printing, has gained widespread interest in the functional prototyping of PBM. 3D printing of polymers enables time-efficient processing with weight reduction and energy savings, addressing the sustainable development goals (such as SDG 9, 11, and 12) associated with the manufacturing of engineering materials. Additionally, the ability of in-field fabrication at the time of need increases the potential implementation of decentralized manufacturing with AM, reducing the resource depletion related to logistics and transportation. Therefore, AM/3D printing of PBM holds significant potential to provide a major enhancement to the current manufacturing capabilities with environmental and economic benefits. Fused filament fabrication (FFF) is an extrusion-based 3D printing technique with increasing popularity for the manufacturing of thermoplastic polymers. The printing technique, processing parameters, material selection, part characteristics, and final application are some of the factors affecting the sustainability and performance of 3D printed PBM. It should be noted that surface finish and internal defects are two of the most important challenges within the FFF method. In addition, the requirement of high thermal processing conditions for high-performing thermoplastic matrices often complicates the processability in FFF. Therefore, this research project aims to identify and optimize the important printing parameters in the FFF method, and to understand the mechanism and formation of internal defects, bulk properties, and tribological performance of 3D printed PBM. Initially, the key process parameters affecting the quality of 3D printed PBM are identified by employing commercially available filaments. The interrelationship between processing-induced defects and their impact on the material properties is explored. Moreover, novel polymeric composite filaments based on the polyether-ether-ketone (PEEK) matrix are developed in-house. Composite filaments are printed and evaluated as load-bearing components. To develop in-house self-lubricating filaments, microscale short carbon fibers (SCF) and nanoscale silicon dioxide (SiO2) particles are incorporated with the PEEK matrix using melt compounding and fabricated with FFF 3D printing. 3D printed parts are evaluated for their thermal, mechanical, and tribological performance. The characteristics of internal porosity and their impact on the material properties of these composites are investigated in this thesis. 3D printed PBM are examined using fractography and tomography to identify the impact of printing parameters on the bulk structure. Raster angle orientation and printing speeds impacted the location and shape of internal voids. Filament fillers were distributed along the material deposition path during the printing process. Adding micro-SCF in the PEEK matrix negatively influenced the formation of voids and interlayer adhesion, while nano-SiO2 improved the fiber-matrix interfacial bonding, reducing the internal porosity. Moreover, the mechanical properties of 3D printed composites significantly increased compared to neat PEEK. Similarly, the crystallization behavior and thermal decomposition temperatures of PEEK were positively influenced by the presence of fillers. Furthermore, 3D printed components were compared with conventional injection/compression molded samples, and the results showed similar tribological performance for both processing methods. The experimentally developed self-lubricating PEEK-based composites exhibited significant improvement in friction reduction and wear resistance compared to commercially available filament options. The multiscale composites showed superior tribological performance in dry sliding, exhibiting up to 50% friction reduction and reduction of specific wear rates by an order of magnitude (at 10-7 mm3/Nm) compared to printed neat PEEK. Analysis of wear mechanisms indicated that neat PEEK and SCF‑PEEK suffered severe abrasion and fiber-matrix debonding with increasing contact pressures, respectively. On the contrary, SiO2-SCF-PEEK composites showed improved wear resistance with smoother surfaces due to the polishing effect of nanoparticles and enhanced stress transfer from the matrix to reinforcements. The increased tribo-contact area with a larger polymer sample size adversely impacted friction characteristics with stick-slip, however, the effect on specific wear rates remains remarkably low. Water lubrication effectively improved tribological performance by reducing running-in duration and fluctuations during the evolution of friction coefficients. In this thesis, 3D printed self-lubricating PEEK composites were successfully fabricated and exhibited comparable friction coefficients and wear resistance to their corresponding compression-molded composites. The findings are evidence that FFF 3D printing can be explored as an alternative technique for the sustainable manufacturing of PEEK-based materials for tribological applications