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Elemental content and radionuclide activity of bottom and fly ashes from Municipal Solid Waste Incineration: a time series analysis
No full textMunicipal Solid Waste Incineration (MSWI) plants pose significant environmental concerns, generating solid by-products, namely Fly Ash (FA) and Bottom Ash (BA). These MSWI residues have received attention due to the presence of valuable elements, Potentially Toxic Elements (PTE), and other contaminants. Radionuclide detection is also critical because they can concentrate in incineration ashes to pose a radiological hazard. Therefore, multi-element and radionuclide analysis was performed on BA and FA, including samples from bag filters containing lime (FAL) and soda (FAS) additives collected from two MSWI plants in northern Italy. BA and FA were sampled in 2013, 2020, 2021, and 2022 for a multi-year assessment, including during the COVID-19 pandemic. Our objectives were to evaluate the potential of elemental flows and radiological impact of the two different MSWI plants. The chemical concentration of 70 elements and the activity of 8 radionuclides were determined using sector Field Inductively Coupled Plasma Mass Spectrometry (ICP-SFMS) and alpha and gamma spectrometry, respectively. Regarding major elements (Fe, Al, Mg, Ti, and P), high mean concentrations were found in BA, followed by FAL and FAS. Notably, in BA samples, Fe, Al, Zn, and Cu averaged 47600, 35300, 4100, and 3500 mg kg−1, respectively, and critical raw materials, namely elements of economic importance such as Mg, P, Ti, and Ba, were concentrated at 16100, 6800, 3500, and 1400 mg kg−1, respectively. The annual flows of elements from MSWI residue streams ranged in the order of 103-104 kg a-1 for Fe, Al, Zn, Cu, Mg and Ti, and the sum of Rare Earth Elements (∑REE) was about hundreds of kg per year. Chondrite-normalized patterns of REE and normalized patterns of selected elements over crustal averages helped to evaluate anthropogenic signals, which enabled us to hypothesise elemental sources related to the input MSW. BA and FA showed a higher content of natural radionuclides than artificial ones. In BA, natural radionuclides, 40K and 210Pb, ranged from 666 to 693 Bq kg−1 and 23.3–48.1 Bq kg−1, respectively. In FA, 40K ranged from 308 to 2198 Bq kg−1 and 210Pb from 17.1 to 534 Bq kg−1. Activity concentration index (ACI) results in all-natural radionuclides below the permissible limit (<1). Still, the significant abundance of 210Pb and 40K, coupled with their complex behaviour, calls for new and continuous evaluation of long-term emissions and the radiological hazard related to MSWI systems. Validerad;2025;Nivå 2;2025-09-03 (u8);Funder: National Research Council of Italy (CNR);Full text license: CC BY-NC-NDSustainable Exploitation of Hidden Resources: approaches for Metal Recovery and Environmental Remediatio
Whole blood selenium concentrations in four free-ranging mammal species from central Scandinavia
No full textBackground Selenium (Se) is an essential element for mammals, with a relatively narrow safety margin between deficiency and toxicity. It is involved in the function of many vital activities and systems, including antioxidants, immune system, thyroid activity, muscle metabolism, and growth by composing different proteins and enzymes. Northern Europe is a Se deficient region, and livestock have been supplemented with mineral bolus or similar for decades to counteract Se deficiency, whereas Finland even adds Se to fertilizers to supplement soil, plants, animals and humans. Relatively few studies have investigated total Se concentrations ([TSe]) in wildlife, and here we present [TSe] measured in whole blood in moose (Alces alces), brown bears (Ursus arctos), wolves (Canis lupus), and wolverines (Gulo gulo) from Norway and Sweden. Results [TSe] in whole blood increased with the trophic level of the species: herbivorous moose < omnivorous bears < carnivorous wolves < scavenging wolverines. Compared to established reference ranges of [TSe] in domesticated species, more than half of all moose sampled and 5% of brown bears were Se deficient. Surprisingly, 49% of bears, 42% wolves and 29% wolverines had [TSe] above recommended references range for domesticated species. In general, [TSe] significantly increased with age and body weight in all sampled species, whereas for most species, there was an additional association with region, year, and season sampled, reflecting variations in Se uptake caused by the element’s geochemical properties related to bedrock and soil availability and atmospheric precipitation. Conclusions Further studies should focus on a wider spatial distribution for these animals and especially include more wolverines to investigate the relatively high [TSe] observed in this species. We also emphasize the importance of measuring Se in poor regions for ecotoxicology studies, since Se deficiency can exacerbate heavy metal toxicosis.Validerad;2025;Nivå 2;2025-12-08 (u8);Funder: University of Inland Norway and the Norwegian Environment Agency (19047048);Full text license: CC BY</p
Dissolution kinetics and mechanisms of calcium aluminate inclusions in CaO-Al2O3-SiO2-(MgO) steelmaking slags
No full textThe dissolution kinetics and mechanisms of solid calcium aluminate inclusions (CaO∙2Al2O3 (CA2) and CaO∙6Al2O3 (CA6)) in CaO-Al2O3-SiO2-(MgO) metallurgical slags at 1550 °C were investigated using high temperature confocal laser scanning microscopy (HT-CLSM). The effects of slag viscosity, CaO/Al2O3 (C/A) ratio, and MgO content on the dissolution time of CA6 and slag MgO content on that of CA2 particles were examined by tracking the time dependent changes of particle projection areas. The obtained results showed that the dissolution kinetics of CA2 and CA6 particles was enhanced by an increase in slag MgO content. Moreover, increasing C/A ratio of slag or decreasing slag viscosity improved the dissolution rate of CA6 particles. Post dissolution analysis using scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDS) combined with thermodynamic calculations revealed the dissolution paths of CA6 particles in slag S3 with C/A ratio 3.8 and S6 with 8.0 wt% MgO, where the dissolution time is out of expectation. It was found that an intermediate solid layer melilite formed around the undissolved CA6 particle in slag S3 with C/A ratio 3.8, reducing its dissolution rate. Conversely, the formation of randomly dispersed intermediate solid products around the undissolved CA6 particle in slag S6 with 8 wt% MgO did not impend their dissolution rate. Finally, based on the obtained findings, two distinct dissolution mechanisms were proposed advancing the understanding of solid inclusion dissolution in metallurgical slags. The findings obtained from this study aim to provide new insights to further improve steel cleanliness for a longevity of the product service life.Validerad;2025;Nivå 2;2025-11-10 (u2);Full text license: CC BY 4.0;Funder: Natural Sciences and Engineering Research Council of Canada; </p
Does career salience influence the link between self-efficacy and task accomplishment in dual-career women? An empirical investigation through dyadic cohesion and flexible work options
No full textThis research investigates the complex career dynamics of dual-career women, focusing on the interrelationships among self-efficacy, career salience, and task accomplishment. The study examines these relationships while considering dyadic cohesion and flexible work options as moderating factors. Utilising a sample of 175 dual-career women with continuous career trajectories, the research employs structural equation modelling to analyse these relationships. The findings reveal that self-efficacy significantly influences task accomplishment, mediated positively by career salience. Furthermore, dyadic cohesion and flexible work options serve to strengthen these relationships. Grounded in Social Cognitive Career Theory (SCCT), the study explores how psychological and social factors impact task accomplishment underscoring the significance of sustainable careers and informing flexible organisational policies supporting dual-career women that enhance gender parity in the workforce. Our study reinforces human resource development’s (HRD) pivotal role in enabling career sustainability by aligning individual aspirations with inclusive organisational practices. It contributes to HRD literature by linking self-efficacy and career salience with supportive work environments for dual-career women. Full text license: CC BY-NC-ND</p
Formal Verification for Preventing Misconfigured Access Policies in Kubernetes Clusters
No full textKubernetes clusters now underpin the bulk of modern production workloads, recent 2024 Cloud Native Computing Foundation surveys report >96% enterprise adoption, stretching from 5G edge nodes and AI/ML pipelines to heavily-regulated fintech and healthcare back-ends. Every action in those environments funnels through the API server, so a single access-control slip can jeopardise an entire fleet. Yet most deployments still rely on a patchwork of Role-Based Access Control (RBAC) rules and policy-as-code admission controllers such as OPA Gatekeeper or Kyverno. In practice these controls are brittle: minor syntactic oversights, wildcard privileges, or conflicting rules can silently create privilege-escalation paths that elude linters and manual review. This paper presents a framework that models both RBAC and admission policies as first-order logic and uses an SMT solver to exhaustively search for counter-examples to stated security invariants before policies reach the cluster. The approach detects policy conflicts, unreachable denies, and unintended permissions. Three real-world case studies are presented to illustrate how the framework reveals latent misconfigurations and validates the soundness of the corrected rules. These case studies include a supply-chain image bypass, an RBAC “shadow-admi” escalation, and a multi-tenant namespace breach. To aid replication and further study, we release a fully scripted GitHub testbed: a Minikube cluster, AuthzForce PDP, admission-webhook adapter, and Z3-backed CLI that recreates each scenario and verifies policies end-to-end. While the framework does not address runtime threats, it closes a critical verification gap and substantially raises the bar for attackers targeting the most widely deployed orchestration platform. Validerad;2025;Nivå 2;2025-11-04 (u4);Funder: Skellefteå Municipality;Full text license: CC BYGreen Transition North (GTN)Digitala Stambanan IndTechRemaNe
Nano-enhanced solar evaporators for desalination: A comprehensive bibliometric review
No full textNanostructures gained popularity in recent years because they exhibit preferable thermo-physical and optical properties for solar desalination applications. Solar steam generation presents an effective solution to worldwide water scarcity issues through its solar-powered desalination process which uses solar energy. To obtain high evaporation rates, the development of cost-effective and highly efficient photothermal evaporators is still challenging. The objective of this bibliometric review is to analyze the keywords, authors, countries, and key sources in the field of nano-enhanced solar evaporators for desalination. The WoS (Web of Science) database was used to collect the documents, and bibliometric analysis was carried out through VOS viewer and Bibliometrix software. The results showed that 270 papers (Research articles: 265 and Review articles: 5) studied nano-enhanced solar evaporators for desalination from 2017 to 2024. Over the prior five years, the number of publications has increased significantly, which shows the imperative for advanced nanostructured photothermal absorbers for solar desalination applications. Commercialization requires improved absorber stability, salt blocking, scalability, low toxicity, and affordability.Validerad;2025;Nivå 2;2025-08-07 (u8);Full text licens: CC BY</p
Perfluoroalkyl substances (PFAS) rejection with plasma polymerized ultrafiltration membranes
No full textThis work investigated the efficient routes for the fabrication of semi-permeable thin films for desalination using plasma polymerization technology. Acrylic acid (AAc) was selected as a precursor for plasma polymerization due to its hydrophilic properties and potential for low fouling functionalization and ability to form flexible, filtration-ready films. The plasma polymerized AAc films were deposited on the top of poly(sulfone) ultrafiltration (PSf UF) membranes to enhance the selectivity of the composite membranes. Different plasma modes such as continuous wave (CW) or pulsed plasma were applied to overcome the brittleness issue. Such narrow pore size UF membranes, with pores less than 10 nm, were further used for rejecting perfluoroalkyl substances (PFASs), a class of persistent environmental chemicals, also known as an emerging threat to public health and the environment. The selectivity and antifouling behavior of the tight UF membranes were investigated against four PFASs differentiated by molecular weight. The tight UF membranes have shown approximately 20 % higher rejection than the pristine PSf. Although the rejection rate was enhanced proportionally with the size of PFAS compounds, membrane fouling became severe as the size of PFAS became close to the molecular cut-off size of the composite membranes. The surfaces of the tight UF plasma modified membranes were more hydrophilic with a water contact angle of 15.1° and negatively charged streaming potential of −31 mV at pH 8, which contributed to the lowest total permeance decline ratio and highest flux recovery rate compared with pristine PSf during each filtration test. The outcome of this study has opened more opportunities for the application of the plasma polymerized membranes for gas separation, water treatment, fuel cells, biomedical devices, and protective coatings.Validerad;2025;Nivå 2;2025-09-08 (u8);</p
Serial recall in spatial acoustic environments: irrelevant sound effect and spatial source alternations
No full textThis study investigated serial recall performance in a complex acoustic scene that included spatialised background sounds and location changes within the target sequence to reflect real-life challenges. The focus is on two effects: the irrelevant sound effect (ISE) and the spatial-source alternation effect (SSAE). Both represent impairment in short-term memory performance of to-be-remembered items: the ISE due to irrelevant background sounds, and the SSAE due to location changes within the target sequence. Although distinct, these effects typically occur together in real-world settings, e.g., listening to multiple speakers in noise, but have not been investigated together yet. Building on the theoretical frameworks of these two effects, this study combines principles from both the irrelevant sound effect (ISE) and the spatial-source alternation effect (SSAE) as a step towards enhancing acoustic complexity in established cognitive tasks. Experiment 1 examined auditory-verbal serial recall using spatially alternating target digits presented at a typical rate (1 item/1 s), with either meaningful or meaningless background speech. Results showed an ISE, with meaningful speech causing greater disruption, but no SSAE - possibly due to either the presentation rate or the spatialised audio scene. To further clarify this, Experiment 2 was conducted with a faster presentation rate (1 item/350 ms) consistent with a previous study, and more spatial target locations (monotic, 10°, 45°, 60°, 90°). An SSAE was revealed for all locations. These findings suggest that the SSAE may mainly be modulated by the presentation rate—given the spatial separation is audible and only emergent at rapid location changes—questioning its applicability to naturalistic listening scenarios. As an attempt to bridge the gap between controlled laboratory settings and more complex listening tasks, these findings help explain how cognitive systems manage competing demands in real-world auditory environments, such as separating speech streams in noise. Validerad;2025;Nivå 2;2025-10-01 (u5);Full text license: CC BY 4.0;For funding information, see: https://www.nature.com/articles/s41598-025-18592-9</p
Seascape genomics: Assisting marine biodiversity management by combining genetic knowledge with environmental and ecological information
No full textBiodiversity, including genetic diversity, is the foundation of ecosystems and supports the well-being of all organisms, including humans. Determining how the marine environment shapes genetic diversity and developing best practices to conserve it requires a multi-disciplinary approach that incorporates genomic and environmental information. Seascape genetics and genomics combine spatially resolved ecological, genomic, and environmental data, coupled with modeling to explore past, present, and future patterns of diversity and connectivity. Seascape genetics and genomics provide scientists and managers with a multi-faceted tool that can be applied across a wide range of species and incorporated into marine spatial management. Despite the proven importance of genetic diversity for species resilience, the incorporation of genetic and genomic data is grossly underrepresented in policy, decision-making, and conservation measures. Here, we aim to support the understanding and access to information on seascape genetics and genomics for conservation and environmental management practitioners. We explain how integrating environment, space, traits, and genetics or genomics can advance marine spatial management. We use two advanced case studies to outline methodology and concepts of seascape genomics and the respective policy context, although management uptake is still pending. Lastly, we review the present status of seascape genomics research and discuss challenges, strengths, and future opportunities by providing a road map. We present a successful management uptake case study that could aid the integration of seascape genomics into biodiversity management. Validerad;2025;Nivå 2;2025-09-05 (u8);Funder: Swiss National Science Foundation (315230_204838/1); Belgian Science Policy project COPE (B2/191/ P1/COPE); Research Foundation Flanders (grant W0.037.10N);Full text license: CC BY-NC-ND</p
Unspoken synergy: Team interdependence with radiographers in trauma alerts - An interview and observational study of trauma teams
No full textIntroduction In Scandinavia, where severe trauma is rare but potentially life-threatening, trauma teams must maintain high performance despite infrequent activations. Although advancements in trauma care have reduced mortality, severe multi-trauma still carries a high mortality risk of death, requiring rapid, coordinated responses from teams of diverse professionals. This study explores the interdependence between various trauma team members, with a particular focus on how radiographers' roles are understood, integrated, and relied upon in trauma care. Methods A qualitative design was employed, with data collected from four Swedish hospitals through interviews and observations. Braun and Clarke’s reflexive thematic analysis method guided the iterative process to identify and generate patterns in the data. Results The analysis generated an overarching theme of Team integration through behavioural interdependence, along with three specific themes: (I) Collaborative interdependence: enhancing team synergy through dynamic role adaption; (II) Social interdependence: fostering trust through interpersonal relationships; and (III) Goal interdependence: aligning objectives for unified success. Conclusion The findings highlight the importance of team-enhancing behaviours to build high-performing trauma teams. Radiographers contribute through adaptive collaboration, technical expertise, and relational engagement. Equally important are the supportive behaviours of team members and leaders—such as clear communication, inclusion in decision-making, and recognition of radiographers' expertise—which enable radiographers to perform effectively. Clearly defined roles and shared objectives reinforce their value in trauma care. Implications for practice Effective team guidance and psychological safety are essential for improving team dynamics and outcomes. Regular, structured team reflections and joint exercises that include all professional roles, especially radiographers, and emphasise shared goals, shared knowledge, and mutual respect, can strengthen interdependence. This approach enhances team performance and supports safer, more efficient care.Validerad;2025;Nivå 1;2025-08-06 (u8);Full text license: CC BY</p