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Public clients creating lead markets for innovation towards sustainability transitions: Market-shaping in the Swedish construction sector
No full textPublic demand is emphasized as a major driving force for environmental innovation addressing societal transitions. In 2007, the European Commission adopted the ‘lead market initiative’ to tackle grand societal challenges across several industrial sectors, of which construction has the greatest sustainability impact. To study how public clients can create lead markets for environmental innovation in construction, we build on recent advancements emphasizing market-shaping strategies as critical for societal transitions. The paper investigates how public construction clients proactively use and combine market-shaping strategies to create lead markets for environmental innovations. Our empirical findings, from a multiple-case study of three public construction clients in Sweden, illustrate how the clients use and combine a broad range of market-shaping strategies related to seven groups of lead market advantages. We contribute to theory by cross-fertilizing market-shaping and lead market literatures and showing how market-shaping strategies interplay in achieving combinatory effects, which incentivize creation of lead markets for environmental innovation towards sustainability transitions.Validerad;2025;Nivå 2;2025-10-01 (u5);Full text license: CC BY 4.0;</p
Privacy by design : Aligning GDPR and software engineering specifications with a requirements engineering approach
No full textContext: Consistent requirements and system specifications are essential for the compliance of software systems towards the General Data Protection Regulation (GDPR). Both artefacts need to be "grounded" in the original text and conjointly assure the achievement of privacy by design (PbD). Objectives: There is little understanding of the perspectives of practitioners on specification objectives and goals to address PbD. Existing approaches to GDPR and PbD do not account for the complex intersection between problem and solution space expressed in GDPR. In this study we explore the demand for conjoint requirements and system specification for PbD and suggest an initial version of an approach to address this demand. Methods: We reviewed existing secondary and related primary studies on GDPR compliance and conducted interviews with practitioners to (1) investigate the state-of-practice in requirements and system specifications for GDPR compliance and (2) understand the underlying specification objectives and goals (e.g., traceability). We developed and evaluated an initial version of an approach for requirements and systems specification for PbD, and evaluated it against the specification objectives. Results: The relationship between problem and solution space, as expressed in GDPR, is instrumental in supporting PbD. We demonstrate how our approach, based on the modeling GDPR content with original legal concepts, contributes to specification objectives of capturing legal knowledge, supporting specification transparency for roles involved, and traceability. Conclusion: In addition to assuring traceability, GDPR demands need to be addressed throughout different levels of abstraction in the engineering lifecycle to achieve PbD. Legal knowledge specified in the GDPR text should be captured in specifications to address the demands of different stakeholders and ensure compliance. While our results confirm the suitability of our approach to address practical needs, we also revealed specific needs for the future effective operationalization of our suggested approach
Foundations of Computation Via Digital Communications
No full textThe explosive growth of distributed data generation — spanning data centers, sensor networks, massive IoT, and edge learning places an unsustainable burden on modern infrastructure, where the energy and latency costs of moving raw data often outstrip those of processing it. While analog over-the-air computation (OAC) promises a solution by exploiting the natural superposition of wireless waveforms to aggregate data in-channel, it remains fragile against noise and fundamentally incompatible with the ubiquitous digital hardware that powers all modern communication systems. This thesis introduces a digital-native framework that unifies communication and computation at the physical layer. Rather than treating channel interference as an obstacle, we engineer the geometry of digital constellations so that the superposition of signals directly yields the desired function value. This paradigm shift transforms the communication link from a passive data pipe into an active computational engine, applicable to any multiple-access channel—whether wired or wireless—without requiring the decoding of individual inputs. We generalize this framework along three axes to ensure scalability and reliability across diverse network environments. First, we develop noise-aware constellation designs that optimize inter-symbol geometry for non-Gaussian and heavy-tailed interference, ensuring robustness beyond standard Euclidean metrics. Second, we introduce a sampling-based reduction strategy that leverages the symmetry of aggregation functions to cut design complexity by orders of magnitude, enabling deployment in massive-scale networks. Third, we extend the framework to vector-valued computation, utilizing spatial degrees of freedom to perform complex, multi-dimensional aggregations in a single transmission shot without relying on perfect channel state information. Finally, to bridge the gap to immediate deployment, we present a closed-form algebraic coding scheme for exact summation. The proposed solution integrates seamlessly with standard quadrature amplitude modulation, eliminating the need for complex optimization and offering a plug-and-play solution for digital aggregation. We validate these contributions through the lens of Federated Edge Learning, demonstrating that computation-by-communication is not only feasible using standard digital protocols but significantly outperforms traditional orthogonal transmission. Collectively, these works prove that computation-by-communication is not only feasible on digitally modulated signals but superior to analog alternatives, paving the way for the next generation of compute-aware networks, enabling energy efficient, scalable, and robust intelligence across any digital infrastructure.QC 20251127</p
Solvent extraction using crown ethers: Selective recovery of potassium from synthetic K-feldspar leachate
No full textThe present study focuses on the selective extraction of potassium from a hydrochloric acid-based feldspar leachate using solvent extraction with crown ethers, CE (dibenzo-18-crown-6 and 12-crown-4). The effects of hydrochloric acid concentration, extractant type, diluent, extractant concentration, and organic-to-aqueous phase ratio on potassium extraction efficiency have been examined. Dibenzo-18-crown-6 diluted in m-cresol was shown to preferentially extract potassium (≈85 %) from highly acidic hydrochloric acid solutions (2 to 6 M), with minimal co-extraction of impurities, such as aluminum and sodium, in a single extraction step. Aluminum, however, was shown to be extracted efficiently (≈99 %) at lower acidities (<0.1 M). The extraction mechanisms were explored using various analyses, such as slope analysis, nuclear magnetic resonance, and scanning electron microscopy showing that dibenzo-18-crown-6 forms a highly stable complex with potassium at 1:1 M ratio, (KCl)(CE), driven by the size compatibility between potassium ions and the crown ether cavity. For aluminum, the extraction mechanism likely involves the formation of a cooperative complex where aluminum ions are associated with the potassium-crown ether complex (AlKCl4)(CE). Increasing the concentration of hydrochloric acid increased potassium ion activity, chloride ion activity, and ionic strength in the solution. These changes would enhance selective potassium extraction over the formation and extraction of the aluminum‑potassium cooperative complex.Validerad;2025;Nivå 2;2025-11-12 (u2);Full text: CC BY license;POTASSIA
Adapting biodiversity conservation in agriculture and forestry to projected climate change in temperate and boreal regions : A synthesis
No full textClimate change creates new challenges for biodiversity conservation. Numerous conservation approaches have been advocated in response and there is a need to compile these into a readily accessible format. We systematically searched scientific literature to summarize recommendations that previous review papers have given for conserving biodiversity in the face of both direct and indirect effects of climate change. As indirect effects of climate change, we considered altered land management and habitat loss, increased disturbances and extreme events, and pests and invasive species. We included recommendations targeting production landscapes dominated by agriculture or forestry in temperate and boreal regions. We found 285 relevant reviews, which in turn cited 874 original research papers as support for the recommendations given. Of the summarized recommendations, 35 % considered direct and 58 % indirect effects of climate change, while 7 % considered both. Indirect effects were considered more frequently in recommendations applicable to agriculture than forestry dominated landscapes. Frequent recommendations were increasing landscape habitat diversity or connectivity, mitigating habitat deterioration, restoring degraded habitats, and adapting management methods in both forestry and agriculture. Most of the recommendations were similar to or consistent with traditional conservation practices, while novel, climate-change specific recommendations were less frequent. We conclude that there is a wealth of research on how to maintain biodiversity in agriculture and forestry dominated landscapes in a world with a warming climate. The summarized recommendations provide a starting point for planning conservation, and the attached database with all considered reviews and original research papers can be used as a source for evidence-based management.
Generalization of Oberlack's definition of the MILD combustion regime
No full textThe Oberlack definition of the MILD combustion limit for premixed systems was derived under the assumption of lean combustion and a one-step reaction. In this study, a generalization of this definition is presented by removing the lean combustion assumption, which leads to a more comprehensive relation between the Damköhler number and temperature, defining the so-called S-curve. The transition of the S-curve to a monotonic function, indicating MILD conditions in the generalized formulation, reveals a dependency on the kinetic parameters of the reaction (reaction orders) and the equivalence ratio. Unlike the previous definition, the proposed solution applies across a broader range of conditions, from rich to lean mixtures, incorporating variations in combustion conditions and the reactivity of the analyzed system. Analytical solutions are not available due to the strong non-linearity of the model; therefore, the results are obtained numerically and are presented as plots and approximation functions, all valid in a wide range of parameter values and applicable to various fuels. The proposed methodology is adaptable to different parameter ranges if needed. Finally, two practical examples, based on hydrogen and methane, illustrate the findings. The results show that reaction orders and the equivalence ratio significantly influence the limit curve defining the MILD combustion regime, with dependencies on the combustion conditions and the chosen fuel.Validerad;2025;Nivå 2;2025-08-18 (u1);Full text license: CC BY 4.0;Funder: National Science Centre, Poland (grant No. 2020/39/B/ST8/02494)</p
Factors associated with postoperative complications after orthognathic surgery - a National Swedish register-based cohort study
No full textPURPOSE: The aim of the study was to identify patient-specific and/or surgery-specific factors that may predict complications following orthognathic surgery, using data from the Swedish National Register of Orthognathic Surgery (NROK). METHODS: In this retrospective register-based cohort study, data from NROK (2017-2020) was analyzed to identify risk factors for complications following single-jaw maxilla surgery, mandibular surgery, and bimaxillary surgery. Outcome data on postoperative infection (POI), removal of osteosynthesis material, re-operation, and persistent neurosensory disturbance (NSD) were collected 12-months postoperatively. RESULTS: Among the 428 patients included in the study, 100 had single-jaw maxilla surgery, 130 had mandible surgery, and 198 had bimaxillary surgery. The site of surgery showed to be the main factor linked to postoperative complications after orthognathic surgery. Mandibular interventions and bimaxillary surgery increased the risk of POI, removal of osteosynthesis material and NSD more than three (3) times compared to maxillary surgery. For re-operation, there was no significant difference between the groups. Other factors associated with increased risk were overweight, age over forty, smoking, and no postoperative antibiotics. CONCLUSION: Mandibular and bimaxillary procedures are associated with increased postoperative complication rates. Age, BMI, smoking, and antibiotic use should be considered in preoperative planning and postoperative care
Quantifying the fatal and non-fatal burden of disease associated with child growth failure, 2000–2023: a systematic analysis from the Global Burden of Disease Study 2023
No full textBackground Child growth failure (CGF), which includes underweight, wasting, and stunting, is among the factorsmost strongly associated with mortality and morbidity in children younger than 5 years worldwide. Poor height andbodyweight gain arise from a variety of biological and sociodemographic factors and are associated with increasedvulnerability to infectious diseases. We used data from the Global Burden of Diseases, Injuries, and Risk FactorsStudy (GBD) 2023 to estimate CGF prevalence, the risk of infectious diseases associated with CGF, and the diseasemortality, morbidity, and overall burden associated with CGF. Methods In this analysis we estimated the all-cause and cause-specific (diarrhoea, lower respiratory tract infections,malaria, and measles) disability-adjusted life-years (DALYs) lost and mortality associated with stunting, wasting,underweight, and CGF in aggregate. We combined the burden associated with mild, moderate, and severe forms ofCGF: stunting was defined as height-for-age Z scores (HAZ) less than –1, underweight was defined as weight-for-ageZ scores (WAZ) less than –1, and wasting was defined as weight-for-height Z scores (WHZ) less than –1, according toWHO Child Growth Standards. Population-level continuous distributions of HAZ, WAZ, and WHZ were estimatedfor 2000 to 2023 using data from surveys, literature, and individual-level study data. The risk of incidence of, andmortality due to, diarrhoea, lower respiratory infections, malaria, and measles was separately estimated in a metaregressionframework from longitudinal cohort data for Z scores less than –1. Finally, fatal outcomes associated withthese diseases were estimated with vital registration, verbal autopsy, and case-fatality data, while non-fatal outcomeswere estimated with surveys as well as health-care utilisation and case reporting data. The exposure prevalence andrelative risk estimates were from continuous distributions, allowing for direct assessment of the attributable fractionsfor mild, moderate, and severe stunting, underweight, wasting, and the combined impact of child growth failurewithin populations. All estimates were age-specific, sex-specific, geography-specific, and year-specific. Findings We estimated that, in children younger than 5 years in 2023, CGF was associated with 79·4 million(95% uncertainty interval [UI] 47·0–106) DALYs lost and 880 000 (517 000–1 170 000) deaths. This represented17·9% (10·6–23·8) of 444 million (434–457) total under-5 DALYs and 18·8% (11·1–25·0) of all 4·67 million(4·59–4·75) under-5 deaths. Compared to stunting (33·0 million [24·1–42·2] DALYs, 373 000 [272 000–477 000]deaths) and wasting (39·2 million [23·8–53·0] DALYs, 428 000 [256 000–583 000] deaths), childhood underweight wasassociated with the largest share of CGF-related disease burden: 52·2 million (21·9–75·1) DALYs and 573 000(236 000–824 000) deaths in children younger than 5 years in 2023. Interpretation CGF remains a leading factor associated with death and disability in children younger than 5 years,despite global attention and focused interventions to reduce the prevalence of associated CGF indicators. Our findingsunderscore the need for policies, strategies, and interventions that focus on all indicators of CGF to reduce itsassociated health burden
PMEL governs autosomal dominant inheritance of white-tail independent of yellow body plumage in chickens (Gallus gallus domesticus)
No full textRegion-specific feather pigmentation is widespread in birds, yet the genetic mechanisms enabling independent control of body and tail plumage remain poorly understood. The white-tailed (WT) phenotype in Wuhua yellow chickens, which exhibit yellow body plumage but pure white tail feathers, provides an ideal model for dissecting such modular genetic regulation. Genetic analysis of F1 and F2 populations (n = 137) derived from a cross with Huaixiang (black-tailed, BT) chickens revealed an autosomal dominant inheritance pattern for the WT trait, with a 3:1 segregation ratio (105 WT: 32 BT; chi 2 = 0.20, P = 0.66) in the F2 generation-independent of the yellow body plumage locus. Integrating genome-wide association study of 47 F2 roosters with population resequencing (n = 50), we identified a highly significant locus on chromosome 33 (P = 1.35E-8) harboring PMEL as the sole credible candidate. Tail follicle transcriptome profiling (4 WT vs. 4 BT) uncovered 1,712 differentially expressed genes, with coordinated downregulation of the entire melanogenesis pathway (normalized enrichment score = -1.914, FDR = 0.003). PMEL ranked among the most strongly suppressed genes (log2FC = -2.18, FDR = 5.58E-06). Furthermore, genome-wide alternative splicing analysis identified 2,764 significant events among 30,473 detected, indicating widespread post-transcriptional regulation. Consistent with this global pattern, the PMEL locus exhibited markedly reduced splicing complexity in WT chickens, characterized by a systematic shift toward simpler isoforms. Thus, four orthogonal lines of evidence-genomic association, transcriptional repression, pathway-level melanogenesis shutdown, and splicing simplification-converge on PMEL as the causal gene underlying this autosomal dominant, tail-specific depigmentation. Our findings establish PMEL as the primary regulator underlying this autosomal dominant trait, paving the way for understanding modular avian coloration and enabling its application in precision breeding programs
Under Pressure : Microcirculatory Dynamics and Capillary Refill Assessment in Provocation and Hemodynamic Stress
No full textBackground: All patients seeking emergency care or admitted to hospital need to be assessed and often monitored over a period. Vital functions are assessed at the bedside with technical equipment and clinical judgement. A commonly performed test, the capillary refill test (CRtest), is supposed to assess circulatory function. The test is performed by pressing the examiners’ index finger onto the patient skin, often for 5 seconds, then rapidly remove the finger and watch the skin regain its original colour as it was before the blanching pressure was applied. The time it takes is called the capillary refill time (CRtime) and less than 2-3 seconds have been recommended as normal, and times longer than that as a sign of circulatory compromise. The CRtest, despite widely used, has been questioned due to its subjectivity, and uncertainty of the test’s external validity. Objectives: The purpose of the study in Paper I was to investigate the repeatability of the CRtest, In Paper II, inter- and intra-observer reliability of the test was investigated, In Paper III, the outcome of the test in a blood loss shock model was investigated. The relationship between the changes in microcirculation to the CRtime in a blood loss shock model was investigated in Paper IV. Methods: In Paper I, CRtests were performed on study subjects on the sternum, the forehead and the finger, in series of 2 and 5 minutes apart. Objectively quantified CRtime, (qCRtime), was obtained through polarized reflectance imaging and a software program. In Paper II, CRtests were performed on pediatric patients in an emergency department and video filmed, and qRCtimes were obtained. The video films were shown to health care staff in a pediatric clinic, and the staff was asked to assess CRtime with naked eye. In Paper III, healthy volunteers were subjected to lower body negative pressure, (LBNP), in a blood loss shock model and CRtests performed and qCRtimes obtained. In Paper IV, the qCRtimes from the healthy study subjects in the LBNP model were compared with simultaneous changes in perfusion, measured as speed resolved perfusion reflecting flow in different vessels, and tissue oxygenation was also measured. Results: In Paper I, there were no statistical differences in qCRtime in a series of CRtests, regardless of when in the series the test was performed. In Paper II, naked eye assessment of CRtimes in children showed poor reproducibility in pediatric nurses and pediatricians, as well as in comparison to qCRtimes. In Paper III, in a blood loss shock model, qCRtimes shortened statistically significantly. In Paper IV, the shortened qCRtimes in Paper III, correlated to a decrease in perfusion and in tissue oxygenation as well as reduced flow in the smallest vessels. Conclusion: The CRtest shows good repeatability, but the test, as it is commonly performed in clinical practice with naked eye assessment, could be questioned for its lack of reproducibility. The CRtest also shows shortening of qCRtime in a blood loss shock model, contradictory to previously believed. The shortening of qCRtime is associated with changes in perfusion. Objective methods for quantification of CRtime with biooptical imaging techniques, as in these studies with polarized reflectance imaging, is valuable in the study of the CRtest and changes in perfusion in provocations and hemodynamic stress