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Highly selective and permeable DDR membranes for CO2/CH4 separation in a wide temperature range
No full textA thin-film (700 nm) DDR zeolite disc membrane was evaluated for separating a 1/1 CO2/CH4 mixture in a wide temperature range (−35 to 180 °C). The highest selectivity of 2325 paired with a high CO2 permeance of 34 × 10−7 mol/(m2·s·Pa) was observed at −30 °C and a feed pressure of 3 bar. At the same feed pressure, the highest CO2 permanence was recorded at + 10 °C reaching 44 × 10−7 mol/(m2·s·Pa), while selectivity remained remarkably high at 1118. High permeance and selectivity were also observed at higher feed pressures. These results surpass all previously published data on CO2/CH4 separation using DDR zeolite membranes and indicate that the membranes have strong potential for upgrading natural gas and biogas. A model describing mass transfer while considering adsorption, surface barrier, and surface diffusion was fitted to experimental single gas permeation data and showed that it can accurately describe the mass transfer in the zeolite pores while indicating that the limiting step was the surface barrier. These findings highlight the potential of DDR membranes for industrial gas purification across a broad range of temperatures and feed pressures.Validerad;2025;Nivå 2;2025-09-25 (u4);Fulltext license: CC BY-NC</p
Advancing the science of consciousness: From ethics to clinical care
No full textSignificant advances in the scientific investigation of the neurobiology of consciousness have been slow to be translated into clinical settings, limited by a lack of generally agreed working definition (e.g., what is consciousness?) and methodology (e.g., how to identify reliable biomarkers/indicators of consciousness? How to improve sensitivity and specificity of the technological identification of consciousness?). In the present paper we aim at proposing potential strategies for reducing the gap between research, clinical practice, and patients’ and their caregivers’ needs regarding disorders of consciousness. By implementing a multidisciplinary (i.e., involving different disciplines) and multiperspective (i.e., involving different stakeholders) approach, the paper focuses on disorders of consciousness: it starts from the review of some of the most promising measures of consciousness from brain activity (i.e., electrophysiology and spectral measures, measures of functional connectivity, complexity-based measures). Next the paper introduces brain responses to illusions as a possible new indicator of consciousness (i.e., a feature that facilitates the attribution of consciousness), and illustrates a possible clinical operationalization of the indicators of consciousness through the case of virtual reality. Finally, the paper analyses a set of urgent ethical issues and describes a model for assessing and dealing with those issues, concluding by elaborating key recommendations for improving the clinical treatment of patients with disorders of consciousness through a better translation of research into clinics
DUALF-D : Disentangled dual-hyperprior approach for light field image compression
No full textLight field (LF) imaging captures spatial and angular information, offering a 4D scene representation enabling enhanced visual understanding. However, high dimensionality and redundancy across spatial and angular domains present major challenges for compression, particularly where storage, transmission bandwidth, or processing latency are constrained. We present a novel Variational Autoencoder (VAE)-based framework that explicitly disentangles spatial and angular features using two parallel latent branches. Each branch is coupled with an independent hyperprior model, allowing more precise distribution estimation for entropy coding and finer rate-distortion control. This dual-hyperprior structure enables the network to adaptively compress spatial and angular information based on their unique statistical characteristics, improving coding efficiency. To further enhance latent feature specialization and promote disentanglement, we introduce a mutual information-based regularization term that minimizes redundancy between the two branches while preserving feature diversity. Unlike prior methods relying on covariance-based penalties prone to collapse, our information-theoretic regularizer provides more stable and interpretable latent separation. Experimental results on publicly available LF datasets demonstrate our method achieves strong compression performance, yielding an average BD-PSNR gain of 2.91 dB over HEVC and high compression ratios (e.g., 200:1). Additionally, our design enables fast inference, with a total end-to-end time over 19x faster than the JPEG Pleno standard, making it well-suited for real-time and bandwidth-sensitive applications. By jointly leveraging disentangled representation learning, dual-hyperprior modeling, and information-theoretic regularization, our approach offers a scalable, effective solution for practical light field image compression
Dear Researchers : Think about the future, for sure, but please don't forget about the present – the Odense Manifesto for academia–industry collaboration at ICSA 2025
No full textDevelopment of quantitative geophysical proxy indicators for urban underground space use : An analysis of Stockholm and its city plan
No full textIn the absence or unavailability of geometric information about underground structures, conventional quantitative indicators of Urban Underground Space (UUS) usage become challenging to obtain. Socio-economic proxy indicators, that are reportedly well correlated with these conventional indicators, are inherently unstable measures given their susceptibility to non-linear human decision-making processes. To address this limitation, we evaluated the potential of geophysical proxy indicators, specifically the magnetic 3D analytic signal (AS), as a basis for UUS assessment. We also assessed the suitability of the magnetic susceptibility model as a framework for three-dimensional subsurface planning. Stockholm's airborne magnetic data acquired in 1995 were processed to generate an AS map that delineated its metro system (tunnelbana) and similar subsurface structures. Observed signatures, correlated with the overlain metro layout, were independently validated on an electrical current density map derived from co-acquired tensor very low-frequency electromagnetic data. Because AS emphasizes the sharp edges of magnetic contrasts, it provides a direct geophysical marker of anthropogenic underground structures and, consequently, an effective proxy indicator for UUS utilization. We introduce two new indicators: analytic signal density (ASD, expressed in nT/m per hectare, interpreted as "the amount of underground structure from a certain depth range that fits a surface area of 1 ha"), and analytic signal per capita (ASPC, expressed in nT/m per 100 person, interpreted as "the amount of underground structure from a certain depth range per capita". Both demonstrate strong correlations, comparable with those of conventional indicators, with population density (r = 0.88 and r = -0.69, respectively). The 3D magnetic susceptibility inversion model further predicted known infrastructure with a vertical accuracy of similar to 20 m, which can be improved with better data quality. Our results indicate that central Stockholm exhibited significantly higher UUS usage in 1995 (> 1.2 nT/m per hectare and < 2.0 nT/m per 100 person) than other Stockholm areas in the same year. The model for 2023, based on population density, estimated a 20-60 % increase in UUS use in central Stockholm since 1995. This trend underscores the need to integrate UUS in planning and development in both the central districts and the development focus areas of Stockholm city plan, where substantial UUS use was also evident. We conclude that, pending the establishment and adoption of standards for UUS use, Stockholm municipality needs a rethink of its population-driven (coined as "first-full first-developed") underground development strategy, identified through the comparative analysis of the geophysical proxy UUS use indicators of 1995 and model estimates for 2023. Given the rapid and extensive coverage afforded by airborne magnetic surveys, ASD and ASPC provide a novel, scalable, and tangible proxy for estimating and comparing UUS use across cities, particularly in data-limited or data-denied environments
Understanding late adolescents’ moral responsibility for climate change : The role of social-ecological factors, worry, and distancing
No full textAddressing climate change requires people in the Global North to avoid high-impact behaviors like car use and air travel. Late adolescents, whose engagement in such behaviors may be restricted by age and parental decision-making, are in a crucial stage for developing a sense of moral responsibility for climate change. Understandingwhy some adolescents cultivate this responsibility is vital, as responsibility relates to both pro-environmentalengagement and well-being. Therefore, this study aims to identify factors associated with late adolescents’sense of moral responsibility. Nature connectedness, parental descriptive norms, and macro climate-changeworry have been positively linked to pro-environmental behavior in previous research, but their role in rela-tion to moral responsibility regarding climate change remains less clear. Similarly, the relationship betweendistancing coping and moral responsibility is yet to be fully understood. In this study we explore ways that thesefactors are associated with late adolescents’ moral responsibility and examine whether these relationships differbetween girls and boys. In 2023, we surveyed 619 Swedish high school students (ages 16–20). We used structuralequation modeling to answer our research questions. Connectedness to nature, parental norms, worry, anddistancing coping were positively associated with responsibility, with parental norms having a stronger effect forboys. Worry partially mediated how parental norms and nature connectedness related to responsibility, with astronger mediation effect for girls in the latter relationship. Distancing coping did not moderate the relationshipbetween worry and responsibility. Our findings are interpreted within social-ecological and emotion-normframeworks, and we suggest promoting responsibility through nature connectedness, role modeling, andconstructive worry management. Limitations, including those related to cross-sectional designs, are discussed.
Percutaneous and surgical management of aortic stenosis in the SWEDEHEART registry (2013-2023) : a nationwide observational study.
No full textBACKGROUND: Management of severe aortic stenosis (AS) has evolved over the past decade, driven by the widespread adoption of transcatheter aortic valve implantation (TAVI). This study aims to assess trends in procedural volumes, patient characteristics, and outcomes for patients undergoing TAVI or surgical aortic valve replacement (SAVR) in Sweden. METHODS: This was a descriptive, non-comparative, nationwide cohort study using the SWEDEHEART registry. We included 21,383 patients who underwent TAVI or SAVR between 2013 and 2023 (11,366 TAVI and 10,017 SAVR). Trends in patient characteristics, preoperative risk, complications and mortality were examined. FINDINGS: TAVI procedures increased from 307 (26.1%, n = 307/1174) in 2013 to 1851 (71.2%, n = 1851/2601) in 2023, while SAVR volumes declined from ∼1000 annually before 2018 to roughly 750 procedures annually. Median age of TAVI patients were 81 (IQR 77, 85) years and 71 (IQR 65, 76) years for SAVR patients. The median EuroSCORE II for TAVI decreased from 5.6 (IQR 3.3, 10.2) to 2.7 (IQR 1.7, 4.6) (p = 0.002), and STS-PROM from 3.3 (IQR 1.9, 4.1) to 1.6 (IQR 1.1, 2.8) (p = 0.0021). Among SAVR patients, EuroSCORE II decreased from 1.5 (IQR 1.0, 2.3) to 1.3 (IQR 0.9, 2.1) (p = 0.022) and STS-PROM from 1.8 (IQR 1.2, 3.0) to 1.6 (IQR 1.1, 2.6) (p = 0.0082). Any in-hospital complications declined significantly for TAVI (29.2%, n = 210/719 to 13.2%, n = 244/1851), while SAVR complication rates increased slightly (18.4%, n = 354/1921 to 18.7%, n = 140/750). In-hospital mortality for TAVI declined from 3.6% (n = 26/719) to 1.0% (n = 18/1851), and 1-year mortality from 11.1% to 6.9% (p = 0.019). SAVR in-hospital all-cause death decreased from 1.6% to 0.4% (n = 3/750) and 5.0% to 2.2% for 1-year mortality (p = 0.013). INTERPRETATION: TAVI has become the predominant treatment strategy for AS in Sweden expanding access within the treated cohort. Despite this, current 2023 SAVR results demonstrate similar in-hospital complication rates compared to TAVI (18.7% vs 13.2%), but lower in-hospital (0.4% vs 1.0%) and 1-year mortality rates (2.2% vs 6.9%). FUNDING: This study was supported by ALF and national research funding bodies
Nocturnal gastro-oesophageal reflux and pulmonary abnormalities on chest CT in a general population: the Swedish CArdioPulmonary BioImage Study
No full textBackground Nocturnal gastro-oesophageal reflux (nGER) is common in people with respiratory diseases, but its association with pulmonary abnormalities is not known.Aim Investigate the association between nGER and pulmonary abnormalities on chest CT in an adult general population.Methods In total, 28 846 individuals from the general population aged 50-64 years completed questionnaires and underwent chest CT, in the Swedish CArdioPulmonary BioImage Study (www.scapis.org). Participants with nGER symptoms on &gt;= 1 night per week were defined as having nGER. Chest CT was evaluated for bronchial wall thickening, bronchiectasis, reticular abnormalities, honeycombing, cysts and ground glass opacities. Ever-smoking, current asthma, inflammatory bowel disease and autoimmune disease were defined as risk factors for pulmonary abnormalities. Analyses were adjusted for sex, age, body mass index, education level and study centre.Results The prevalence of nGER was 9.4%. Among participants with risk factors for pulmonary abnormalities (n=4004), having nGER was positively associated with bronchial wall thickening (adjusted OR (aOR) (95% CI): 1.25 (1.07 to 1.48)) and reticular abnormalities (aOR (95% CI): 1.51 (1.04 to 2.17)), but negatively associated with cysts (aOR (95% CI): 0.68 (0.48 to 0.97)). Among participants without risk factors for CT abnormalities (n=2555), nGER did not relate with pulmonary abnormalities.Conclusions In a middle-aged general population, nGER was not associated with pulmonary abnormalities on chest CT. However, in the presence of other risk factors for pulmonary abnormalities, nGER was associated with bronchial wall thickening and reticular abnormalities. Persons with nGER and risk factors for pulmonary abnormalities should, therefore, be evaluated for respiratory disease and treated appropriately.Funding Agencies|Swedish Heart and Lung Foundation [20210558, 20230610]; Knut and Alice Wallenberg Foundation; Swedish Research Council, VINNOVA (Sweden's Innovation Agency); University of Gothenburg; Sahlgrenska University Hospital, Lund University; Skane University Hospital, Linkoeping University; University Hospital, Karolinska Institutet; Karolinska University Hospital; Uppsala University and University Hospital; Umea University and University Hospital</p
Interactions between litter-feeders and the burrowing earthworm A. caliginosa do not affect mineral-associated C addition in recent spoil material
No full textSoil macrofauna affects litter decomposition by modifying organic matter availability for microorganisms. Litter-feeders accumulate partially decomposed organic matter at the soil surface, while burrowing earthworms mix the organic matter with mineral particles. Synergistic effects of the combined presence of litter-feeders and burrowing earthworms through facilitation are expected but seldom tested. We performed a three-months microcosm experiment in which we tested the effect of the presence of litter-feeders (an epigeic earthworm and an isopod) on the biomass of the burrowing earthworm Aporrectodea caliginosa and on C incorporation into individual soil organic matter fractions. We used a recent post mining soil, limited in food resources to promote interactions, and alder litter which is suitable food for soil invertebrates. We hypothesized that A. caliginosa would be positively affected by the presence of litter feeders, and that this would impact C addition to the more stable fractions. Contrary to our hypotheses, we found no variation in the biomass of A. caliginosa among treatments, as this species could feed directly on alder leaves. The accumulation of poorly stabilized particulate organic C was negatively affected by the presence of both earthworm species (i.e. less than cumulative), suggesting either that A. caliginosa fed on the particulate organic matter produced by the epigeic earthworm, or that competition for the limiting food resources took place. However, A. caliginosa promoted a similar increase in stable mineral-associated C in all treatments. This confirms the plasticity of A. caliginosa regarding food resources observed in other experiments, and shows that the effect of the burrowing earthworm A. caliginosa on stable C accumulation is not necessarily mediated by litter-feeders in the presence of litter of good quality
Phthalates and pharmaceuticals in soil, groundwater, and surface water downgradient of a wastewater soil infiltration system
No full textThis study investigates the occurrence, attenuation, and ecological risks of phthalates and pharmaceuticals in a long-operating wastewater soil infiltration system in northern Sweden. Concentrations of 15 phthalates, 67 pharmaceuticals, caffeine, and acesulfame K were measured in influent wastewater, groundwater, soil, and a downgradient pond across multiple seasons. Results showed that most micropollutant removal occurred in the unsaturated soil zone prior to groundwater recharge, possibly due to processes such as biodegradation and sorption. Substantial reductions were observed for caffeine (>99 %), carbamazepine (>96 %), losartan (>99 %), and phthalates (51 ± 72 % and 92 ± 5 %), with the higher attenuation for phthalates comparable to conventional activated sludge treatment. In contrast, compounds such as metoprolol exhibited moderate reductions (>71 %), while others showed low or even negative attenuation, including diclofenac (46 % and −180 %) and ibuprofen (33 % and −11 %). After groundwater recharge, only ibuprofen showed attenuation beyond dilution, although the mechanisms for this remains unknown. Several pharmaceuticals, including metoprolol, irbesartan, and metformin, were detected in soil samples, though it is unclear whether they were sorbed to the soil matrix or present in porewater. In downgradient surface water, diclofenac and ibuprofen exceeded risk quotient thresholds, while oxazepam surpassed the lowest predicted no-effect concentration (PNEC) in one sample, indicating ecological risks. Overall, the findings highlight both the strengths and limitations of soil infiltration systems in mitigating micropollutant contamination, emphasizing the importance of vadose zone processes while underscoring uncertainties in sorption and degradation mechanismsFull text: CC BY license;</p