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Investigation of internal density variation in Scots pine using X-Ray computed tomography and image analysis
No full textResinwood formation in Scots pine (Pinus sylvestris) resulting from Cronartium pini infection represents a critical quality defect that substantially reduces timber value and complicates industrial processing decisions in the Nordic Forest industry. Current timber grading protocols rely exclusively on visual surface inspection, which cannot detect internal resin accumulation patterns essential for optimal sawmill operations and volume yields. This knowledge gap generates cascading economic inefficiencies throughout timber processing, as sawmills cannot optimise cutting patterns without comprehensive internal defect information. This doctoral research addresses these fundamental limitations by developing and validating non-destructive methods for detecting and segmentation of internal resinwood distribution using X-ray computed tomography (CT) imaging. The pathophysiological basis for this approach stems from the host defence mechanism whereby C. pini infection triggers systematic hyperproduction of oleoresin compounds that infiltrate wood tissues, generating distinguishable radiographic density variation, so the research work bridges this gap by integrating two approaches: Algorithm Development: An automated segmentation pipeline combining Gaussian Mixture Models (GMM), multi-directional ray-casting, and morphological refinement was developed to distinguish resinwood from healthy tissues in CT imagery. The method processes ~7,000 slices per log, achieving high sensitivity for sapwood (0.98) and heartwood (0.80) segmentation. Resinwood detection attained moderate precision (0.25), limited by density overlaps with heartwood and CT image artefacts.Qualitative Feature Identification: CT analysis of paired green- and dry- state specimens revealed three diagnostic resinwood signatures: (a) growth-ring distortions, (b) non-concentric cambial development, and (c) ground-glass opacity patterns. Resin extraction validated these features, confirming increase resin content in CT-identified zones (41% vs. control: 2%, p < 0.001).Key novel scientific contribution: Evaluated probabilistic framework for resinwood segmentation through industrial CT imaging.Dual-state (green/dry) CT scans enabling the utilisation of comparison imaging data for resinwood mapping in logs.Open-source implementation supporting model development in pilot testing for sawmill-related research and development.Challenges persist in distinguishing pathological resin accumulation from natural impregnation heartwood density gradients and moisture driven influenced false detections. Future work will integrate multi-threshold GMMs, more noise reduction, and spatial feature descriptors (e.g., resin morphology) to enhance specificity. This research establishes a foundation for data-driven defect detection and have potential to improve volume yield in production and processing optimisation in digitally assisted sawmilling.CT-Woo
Reciprocal effects between illicit drug use and mental health conditions among healthcare workers in Sweden : A one-year follow-up study
No full textBackground: Research suggests a comorbidity between illicit drug use and mental health conditions. However, it remains unclear whether illicit drug use serves as a risk factor for, or a consequence of, mental health conditions in healthcare workers (HCWs). This study aimed to 1) examine the prevalence of illicit drug use among HCWs in Sweden and 2) investigate the bidirectional relationship between illicit drug use and mental health conditions(i.e., depression and burnout). Methods: Data from the 2022 and 2023 Longitudinal Occupational Health Survey in Healthcare Sweden (LOHHCS) were used. The data included 3280 HCWs (50.3 % physicians and 49.7 % nurses). Questionnaires assessed illicit drug use frequency, burnout complaints (BAT-12), and depression (SCL-CD6). Cross-lagged panel models (CLPMs) were used to examine the reciprocal relationships over the two studied time-points between illicit drug use and mental health conditions. Results: The prevalence of illicit drug use in 2022 was 1.3 %, which increased slightly to 1.6 % one and a half years later, in 2023. Using two-wave panel data, results revealed a bidirectional effect between illicit drug use and burnout. However, while depression was associated with subsequent illicit drug use, the reversed association was not observed. Conclusions: These findings suggest that illicit drug use plays different roles in relation to burnout and depression among healthcare workers. This highlights the importance of integrated treatment strategies and preventive measures that address both illicit drug use and mental health conditions—especially burnout—simultaneously.
Low-oxygen freshwaters as ecological niches for mercury methylators
No full textMethylmercury (MeHg) is a hazardous neurotoxin, predominantly formed by microbial transformation of inorganic mercury in oxygen-depleted aquatic and terrestrial ecosystems. The ongoing deoxygenation of aquatic ecosystems due to global warming is likely to expand microbial niches for MeHg production. Although mercury methylators have also been reported to thrive in oxyge-deficients conditions in a few marine and freshwater ecosystems, there is a lack of comprehensive understanding of how they are distributed in freshwater systems. In this study, we retrieved hgcA genes, genomic marker for mercury methylation potential, from 586 metagenomes from the water column of 186 freshwater systems. Overall, hgcA genes were detected in the water column of 30 lakes, with the highest richness and abundance being detected in anoxic (0 mg O2L-1) and hypoxic (>0–2 mg O2L-1) compared to oxic conditions (>2 mg O2L-1). Although Desulfobacterota had the highest hgcA gene richness across most freshwater systems, certain systems were dominated by hgcA genes from Bacteroidales and Kiritimatiellales, implying metabolic and ecological versatility of mercury methylators as a group. Our findings suggest that projected expanding deoxygenation may lead to new niches for mercury methylators in inland waters
Exploring linguistic similarity and sociolinguistic variation in multilingual transfer of Romance perfective tenses in Italian as L3
No full textA comparative analysis of industrial involvement and licensing in the open source software ecosystems of four IoT standards
No full textContext: IoT standards are vital for interoperability and longevity, with Open Source Software (OSS) implementations preventing vendor lock-in. These implementations form vast software ecosystems on platforms like GitHub, where industrial participation is crucial. Goal: This study characterizes industrial involvement (participation, leadership, collaboration) across the software ecosystems of four IoT standards (LwM2M, NB-IoT, CoAP, Zigbee) from different standards-setting organizations. It also investigates how software licensing, particularly OSS licenses, reflects and shapes this involvement. Method: We analyzed software projects related to these standards that are publicly available on the GitHub platform, examining authorship of commits, bug reports, pull requests, and metadata like licenses. We identified organizational affiliations (corporate or academic) of contributors to assess their presence and leadership. We performed a licensing analysis to understand the legal frameworks governing these projects. Results: Our research shows significant diversity in ecosystem scale and activity, with a consistent pattern of major corporate and organizational leadership in highly active projects. Despite robust institutional involvement, a pervasive issue is the widespread absence of explicit software licenses, even in collaborative and active repositories. When licenses are present, permissive OSS licenses (e.g., Apache-2.0, MIT) dominate. This indicates a complex and often ambiguous legal landscape. Conclusion: IoT standard ecosystem growth is driven by established organizations. Addressing the prevalent lack of licensing is crucial for fostering clearer collaboration, mitigating legal risks, and ensuring long-term sustainability and adoption of these foundational technologies. CC BY 4.0© 2025 The Author(s)April 2026Correspondence Address: G. Robles; Universidad Rey Juan Carlos, Madrid, Spain; email: [email protected]; CODEN: JSSODDeclaration of competing interestThe authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Gregorio Robles reports financial support was provided by Swedish Knowledge Foundation (KK-stiftelsen). Björn Lundell reports financial support was provided by Swedish Knowledge Foundation (KK-stiftelsen). Jonas Gamalielsson reports financial support was provided by Swedish Knowledge Foundation (KK-stiftelsen). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.AcknowledgmentsWe acknowledge the use of Google Gemini to ensure linguistic accuracy and enhance the readability of this article. This research has been financially supported by the Swedish Knowledge Foundation (KK-stiftelsen) and participating partner organizations in the SUDO project. The authors are grateful for the stimulating collaboration and support from colleagues and partner organizations.</p
Sustainable Ventures And External Financing:Empirical Insights On The Financing Access Gap
No full textReaching sustainable development is one of the most pressing concerns of our time. From an industry perspective, this calls for a sustainable industrial transformation, including a foundational shift in long-standing practices and social norms that currently set unsustainable industry trajectories. High expectations have redirected the focus to sustainable ventures with the potential to address sustainability challenges as entrepreneurial opportunities while integrating sustainability goals into their core values. These ventures not only have the potential to challenge but also to surpass incumbent firms in contributing to radical innovations and sustainability solutions, positioning them as key catalysts and entrepreneurial pioneers in the forthcoming sustainable industrial transformation. However, a key factor in enabling these ventures to succeed lies in their ability to secure financing to sustain and grow their businesses. Despite the rapid growth of sustainable financial markets and a growing interest among financial actors in leading the industrial transition, the actual financing reaching sustainable ventures remains scarce. Sustainable ventures tend to misalign with current sustainable finance frameworks and deviate from the type of investment that financiers typically prefer. These circumstances represent a critical shortcoming and a significant impediment for sustainable ventures seeking to realize their full potential in generating sustainability impacts. In complement to traditional entrepreneurial finance, which regularly explains financing gaps through agency-based reasoning and information asymmetric problems, this thesis argues for the need to further investigate the social underpinnings of this financing gap, suggesting that current theorizing may not fully explain the financing access gap faced by sustainable ventures. From a socialized perspective, information may not be missing but rather contested. Drawing on the sustainable entrepreneurship and entrepreneurial finance literature, the theoretical framework of this thesis integrates perspectives from organizational identity theory, reference points theory, and the dynamic capabilities view, with the purpose of advancing understanding of access to external financing in sustainable ventures. More specifically, this thesis seeks to understand how sustainable ventures' organizational identity, performance reference points, and dynamic capabilities relate to access to external financing. This thesis adopts a qualitative research approach implemented through a multiple case study strategy. 53 case companies representing finance-seeking sustainable ventures, and their associated financers were selected based on theoretical sampling. Data were mainly collected from 109 semi-structured interviews, supplemented by secondary data. Data were analyzed following a stepwise and iterative coding process to identify emerging codes, themes, and overarching categories, inspired by the method of Gioia et al., (2013). To ensure a comprehensive analysis, the cases were considered holistically rather than in isolation. This thesis integrates the findings of four appended studies into a framework for understanding the finance access gap and the (mis)alignment between sustainable ventures and external financiers in financial exchange situations. As a theoretical lens, organizational identity theory[1] is used to analyse the study’s findings as a coherent set of values (hybrid identity), practices (performance reference points), and routines (dynamic capabilities) that tends to shape the self-defining identity of sustainable ventures and, furthermore, to inform the identity interpretations made by external financiers. The framework reveals an almost dichotomous misalignment between the ventures' self-defining identities and the identity interpretations of private debt and equity financiers. This identity misalignment tends to negatively influence funding decisions, expressed as pending or declined funding. Conversely, the framework identifies a strong identity alignment between the ventures' self-defining identity and the identity interpretations of corporate debt and equity financiers. This alignment thus tends to positively influence funding decisions, leading to pending or accepted funding, although the funding is associated with a significant risk of losing ownership and control. Moreover, the potentially contradictory identity interpretations of financiers tend to trigger critical identity work in sustainable ventures, who seek to balance the financier's conflicting identity expectations and identity change demands while strengthening their self-defining identity, including maintaining sustainability-driven values and aspirations. From a socialized perspective, the sustainability-driven identity of sustainable ventures seem to significantly constrain their access to external financing, primarily because they are interpreted as misaligned with private debt and equity financiers’ perception of a financially viable funding prospect. Furthermore, they are categorized as outside the scope of conventional financing frameworks and practice. Specifically, these financiers expect ventures to display conventional industry practice or "business as usual" to increase fundability. This represents a serious shortcoming because such expectations conflict with the very values, practices, and routines that define the venture's self-defining identity and that are held to be vital to achieve measurable and positive sustainability outcomes beyond the principles of “reducing harm”. This thesis contributes to the emerging literature on sustainable entrepreneurship by proposing a framework for understanding the financing access gap, which seems to prevent sustainable ventures from growing and expanding. Moreover, this thesis contributes to organizational identity theory, reference points theory, and the dynamic capability view by demonstrating how sustainable ventures' hybrid identity, multiple reference points, and sustainability-oriented dynamic capabilities tend to be associated with access to external financing in adverse ways. In addition, the findings carry novel implications for both policy and practice and offer empirical insights that may enhance the development of better metrics and models to support the advancement of sustainable venturing and the leverage of potentially transformative sustainability innovations. [1] (see Albert & Whetten; 1985; Corely et al., 2006; Pratt 2018; Whetten, 2006)
Crustal structure of the central Norwegian Caledonides and underlying basement with the Atnsjø tectonic window, inferred from magnetotelluric data
No full textMuch of the Norwegian upper crust was shaped by Caledonian thrusting and post-orogenic extension. We investigate the electrical conductivity structure of the crust and associated thrusts and detachments using magnetotellurics to obtain a better understanding Paleozoic tectonics. New magnetotelluric data were collected over an area of c. 60 × 70 km that includes the Gudbrandsdalen Antiform and Atnsjø tectonic window in central Norway.The final 3D electrical conductivity model reveals a highly resistive crustal block, extending E–W along the Gudbrandsdalen Antiform and from the surface to several tens of kilometres depths, imaging the parautochthonous Precambrian basement. No major thrust or detachment has been mapped under the Atnsjø tectonic window, which is therefore considered to most likely represent autochthonous or parautochthonous Baltica basement. Several conductors are imaged along the edge of the magnetotelluric survey, which can be correlated with a major Caledonian thrust and structures in the Precambrian basement.Full text license: CC BY 4.0;Funder: Norwegian Geological Survey;</p
Upper-secondary school segregation in stockholm metropolitan area : The relationship between commuting distance and school characteristics
No full textAlthough free school choice policies are often proposed as strategies to decouple residential and school segregation, research has found that they may actually increase segregation. This study investigates an underexplored aspect of these policies: the role of commuting in influencing school segregation patterns. Using Swedish register data from Stockholm Metropolitan Area, we analyse ethnic and socioeconomic segregation across residential neighbourhoods and upper-secondary schools. We examine students' distances to the nearest schools offering their chosen programs and their actual commuting distances in relation to the schools' characteristics. Our findings reveal that students with immigrant backgrounds, despite living closer to the nearest schools offering their chosen programs than native peers, tend to travel longer distances to attend their chosen schools. For native students, choosing nearby schools is associated with selecting more privileged institutions that have higher proportions of native students and higher average income levels. In contrast, students with immigrant backgrounds often travel longer distances to reach schools with characteristics similar to those attended by native students. These results challenge simplistic assumptions about the segregation-reducing effects of free school choice policies and highlight the complex interplay among the uneven distribution of educational opportunities, home-to-school mobility, and school selection strategies
The impact of policy design on public opposition to restrictive climate policies
No full textWith the growing emergency of global warming and biodiversity loss, and difficulties to reduce the impact of consumption, some researchers and government authorities have raised the idea of using rationing to reduce individuals' climate impact. Yet public opinion research on such policies and whether policy design affects public attitudes remain scant. Surveying over 3000 Swedish citizens, we provide the first experimental test of people's attitudes towards the rationing of transportation fuels and red meat in two identical, but separate, conjoint experiments. Our results reveal that the vast majority of our sample have conditional preferences, meaning their support for rationing is contingent on its specific design. In contrast, 23 % of the sample remain strongly opposed to all fuel and meat rationing proposals, irrespective of their design. Opposition to rationing decreases if people are allowed to consume more, if the allocation takes people's needs into account, if people are allowed to consume similar amounts over time and if the price for consumption does not rise unchecked. We uncover clear heterogeneities in design preferences depending on respondent characteristics, particularly for perceived fairness and effectiveness of rationing and current consumption behavior. Our findings add to the growing evidence indicating that the design of climate policies matters for people, but they also uncover the limits of policy design when climate policies have clear material implications
Two-step digestion pathways of hydrogels from pea proteins
No full textHypothesis: Digestion pathways of plant proteins are of high relevance to optimize bioavailability and allergenicity profiles of sustainable and vegan food products. Understanding the structural breakdown of solid food presents a particular challenge, due to the complexity to realize a good model system suitable for comprehensive multi-technique characterization under realistic conditions. Experiments: We used a microfluidic chip to study the structural evolution during in-vitro digestion of solid gels from pea proteins. The gel structure was probed in-situ combining confocal microscopy, small-angle neutron and X-ray scattering using the same experimental platform. SDS-PAGE analysis was performed on related solution and gel samples subjected to different digestion times. Findings: Combining multiple techniques we reach a multi-scale picture of gel digestion, revealing the breakdown of a more homogeneous gel into more open connected domains with hierarchical internal structures. SDS-PAGE outlines effects of processing on resulting digestion pathways. As central result, we observe a clear two-step digestion process across techniques, switching at about 8-10 min from the initial response to long-term digestion. Overall, the presented methodology holds promise for detailed structural information in future studies aimed at developing new foods with optimized mechanical, nutritional value, and reduced allergenicity