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Behind the Scenes of Pro-Environmental Tourist Behavior : Exploring Barriers, Drivers, and Antecedents
No full textThis mixed-method dissertation explores the barriers, drivers, and antecedents of pro-environmental behavior in tourism, with a focus on Generations Y and Z. Based on interviews with Generation Z consumers, the first study identifies primarily low motivation, but also limited knowledge, and restricted opportunities as key barriers to pro-environmental travel engagement. It proposes structural and informational interventions to make eco-friendly options more appealing and accessible. The second study delves into Reddit discussions, uncovering that while users recognize the link between tourism and climate change, low self-efficacy and ten perceived barriers hinder important behaviors. The findings provide insights into which tourism choices are important for consumers when striving to minimize their climate impact. The third study draws on survey data to compare Generations Y and Z on psychological constructs influencing their pro-environmental behavior. The results show that Generation Y reports higher levels of psychological empowerment and perceived social norms. Perceived behavioral control is identified as the strongest predictor of personal norms, followed by psychological empowerment and awareness of consequences. The study also reveals a striking gap: while 65% of respondents report strong personal norms to protect the environment, less than 3% of the total sample chose to learn more about eco-friendly travel when given the opportunity in the online setting. The fourth study, also survey-based, examines how subjective knowledge, awareness of consequences, environmental concern, and psychological empowerment influence personal norms and behavioral intentions. A moderation analysis finds that environmental concern has a stronger impact among individuals with higher objective environmental knowledge. The dissertation presents key lessons learned during the PhD journey, offering a discussion of strengths, areas for improvement, and integrated insights from all studies.Denna avhandling som är baserad på en blandad metodansats undersöker barriärer, drivkrafter, och faktorer som påverkar miljövänligt beteende inom turism med fokus på Generation Y och Z. Den första studien, som bygger på intervjuer med konsumenter från Generation Z, identifierar framför allt låg motivation, men även begränsad kunskap och begränsade möjligheter som centrala hinder för engagemang i miljövänligt resande. Studien föreslår strukturella och informativa åtgärder för att göra miljövänliga alternativ mer tilltalande och tillgängliga. Den andra studien undersöker diskussioner på Reddit och avslöjar att även om användare inser kopplingen mellan turism och klimatförändringar, hindras viktiga beteenden av låg självförmåga och tio upplevda barriärer. Resultaten ger insikter om vilka val inom turism som är viktiga för konsumenter som strävar efter att minimera sin klimatpåverkan. Den tredje studien bygger på enkätdata och jämför Generation Y och Z utifrån psykologiska faktorer som påverkar miljövänligt beteende. Resultaten visar att Generation Y rapporterar högre nivåer av psykologisk egenmakt och upplevda sociala normer. Upplevd beteendekontroll identifieras ha störst påverkan på personliga normer, följt av psykologisk egenmakt och medvetenhet om konsekvenser. Studien visar också ett signifikant gap: medan 65% av respondenterna rapporterar starka personliga normer för att skydda miljön, valde mindre än 3% av det totala urvalet att lära sig mer om miljövänligt resande när de fick möjlighet i den digitala miljön. Den fjärde studien, som också bygger på enkätdata, undersöker hur subjektiv kunskap, medvetenhet om konsekvenser, miljöoro och psykologisk egenmakt påverkar personliga normer och beteendeintentioner. En moderationsanalys visar att miljöoro har större effekt bland individer med hög objektiv miljökunskap. Avhandlingen presenterar centrala lärdomar från doktorandresan och innehåller en diskussion om styrkor, förbättringsområden och integrerade insikter från samtliga studier.
Sublingual immunotherapy in children with asthma : a population-based register study
No full textBackground: Daily sublingual immunotherapy (SLIT) for 3 years reduces symptoms of allergic disease and induces tolerance. Real-life data from children with asthma receiving SLIT are scarce. Objective: We used population-based data to describe characteristics, SLIT duration, and changes in morbidity in children with asthma prescribed SLIT. Methods: The study included children (5-17 years) with asthma who were prescribed SLIT, and who were registered in the Swedish National Airway Register (SNAR) before SLIT initiation (N = 1,514), of whom 782 had post-SLIT recordings in the SNAR. Age, sex, Asthma Control Test score (≤19 denotes uncontrolled asthma), spirometry data, number of SLIT tablets dispensed, and socioeconomic background were extracted from the SNAR and other national registers. SLIT duration was classified as <4, ≥4, >12, or >24 months. Results: SLIT was more common in boys (69%) and adolescents (71%). Most children had parents with higher education (70%), and 25% had uncontrolled asthma. SLIT duration of ≥4, >12, and >24 months was identified in 86%, 50%, and 30%, respectively. Parents with higher education were associated with SLIT duration of ≥4 months (odds ratio = 3.69; 95% confidence interval 2.75-4.96). SLIT duration of >12 months was associated with lower risk of post-SLIT uncontrolled asthma (adjusted odds ratio = 0.49; 95% confidence interval, 0.25-0.99). No associations were found between SLIT duration of ≥4, >12, or >24 months and changes in spirometry. Conclusion: Longer SLIT duration was associated with higher education in parents and lower risk of uncontrolled asthma. Measures to improve persistence in SLIT in children with asthma may have important clinical implications
Optimization and re-operation of the fission fragment spectrometer VERDI
No full textThe VElocity foR Direct particle Identification (VERDI) spectrometer is a Fission Fragment detection instrument based on the double-energy double-velocity (2E-2v) method. The aim is to determine fission fragment yield distributions with a mass resolution of at least A/Delta A = 100. VERDI features two time-of-flight (TOF) sections, each equipped with a micro-channel plate (MCP) detector for the start time-of-flight determination and up to 31 passivated implanted planar silicon (PIPS) detectors for fragment time-of-flight (TOF) and energy measurement. We report on improvements in the data acquisition and the technical performance of our time pickup and energy detection
Protein-capped mesoporous silica SBA-15 enables protease-responsive and controlled antimicrobial peptide delivery
No full textMesoporous silica materials are promising carriers for antimicrobial peptides (AMPs), offering a versatile platform for combating bacterial infections. However, achieving high loading efficiency and controlled AMP release under physiological conditions remains a challenge. This study introduces a protein-capped mesoporous silicabased delivery system for treating topical bacterial infections. The system leverages elevated protease activity at infection sites to trigger the release of the sequence-optimized antimicrobial lipopeptide L-6-C5 (SOAP), facilitating efficient bacterial killing. SOAP was loaded into aminopropyl-functionalized SBA-15 mesoporous silica (amino-SBA-15) and capped with bovine serum albumin (BSA) or casein, forming amino-SBA-15SOAP@protein. Protein adsorption prevented premature SOAP release while enabling protease-triggered delivery. BSA capping achieved 92.6 +/- 0.2 % loading efficiency and enhanced peptide retention by 4.5-fold compared to non-capped particles, while casein yielded only a 1.25-fold increase. In the absence of proteases, SOAP release followed first-order kinetics, resulting in sustained release over 6 days. When exposed to trypsin, the release mechanism changed from diffusion-based to anomalous non-Fickian transport with zero-order kinetics, enabling rapid and efficient SOAP release. Proteolytic degradation of the protein cap also accelerated particle degradation and aggregation, offering insights into release dynamics under physiological conditions. The BSA-capped systems (amino-SBA-15-SOAP@BSA) showed effective bacteriostatic activity against Staphylococcus aureus (S. aureus), low hemolytic activity, and high cytocompatibility toward human dermal fibroblasts, outperforming free SOAP. Additionally, BSA capping reduced nonspecific protein binding in serum-rich media. By integrating sustained SOAP delivery with protease-triggered release, the amino-SBA-15-SOAP@BSA system addresses key limitations in AMP delivery, providing a promising strategy for controlled and localized AMP delivery in the treatment of topical bacterial infections.Funding Agencies|Swedish Research Council (VR) [2021-04427]; Swedish Foundation for Strategic Research (SSF) within the HEALiX project [RMX18-0039]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Centre in Nanoscience and Technology at LiTH, CeNano</p
Analysis of high flux membranes for desalination in waste-heat driven vacuum membrane distillation plants: Experimental validation and techno-economic analysis
No full textVacuum membrane distillation is a promising technology for seawater desalination, as it enables high recovery ratios, with reasonable thermal and minimal electric consumption. Ceramic membranes can offer notable advantages over polymeric membranes, mainly due to their robust thermal and mechanical stability, yet they have limited representation in the literature. Accordingly, this work investigates ceramic membranes and their techno-economic performance for large scale desalination plants, with target recovery ratios above 85 %. First, a one-dimensional model for multilayered membranes was developed in MATLAB, validated against experimental data of water fluxes with different membrane materials, including ceramic ones, specifically collected within this work. This also enabled the fitting of the membrane characteristic parameters with the collected experimental data. With the aim of reducing the thermal consumption, a full-scale plant layout was defined with various stages in cascade and a sensible waste heat source at 90 °C. Results demonstrate that thermal consumption level in the 180–250 kWh/m3 range is possible, with average water fluxes around 20 kg/(m2·h). With reasonable assumptions on capital costs and plant availability, the levelized cost of water was found to be between 3 and $8/m3.Validerad;2025;Nivå 2;2025-12-02 (u4);Fulltext license: CC BY-NC-ND</p
Water hyacinth (Eichhornia crassipes) biomass characterization for a potential exploration as an agriculture soil enhancer : Linking multi-location biogeochemical profiles to ecotoxicological safety
No full textWater hyacinth (WH) is an invasive aquatic species for which no universal biomass management strategy exists, although many developing countries use it in agriculture with limited understanding of its potential environmental impacts. As WH is an effective bioaccumulator it is essential to assess its composition and quantify potentially harmful elements before this surplus green biomass can be effectively valorised. Determining the thresholds for their effects is crucial to define safe and sustainable uses. In this context, this study characterized WH biomass from six Portuguese locations (four northern and two southern), focusing on nutrient and potentially toxic element (PTE) profiles, sugar, protein, and structural composition. Furthermore, the ecotoxicological profile of aqueous extracts from each WH biomass was evaluated using several freshwater species ( Raphidocelis subcapitata, Brachionus calyciflorus, Daphnia magna, and Danio rerio ) and multiple endpoints, to benchmark safe agricultural application rates. Structural analysis revealed tissue type (leaves, floaters, roots) had greater influence than sampling location, with roots showing highest absorbance linked to lignin, proteins, and cellulose. These wall components provide metal-binding sites, explaining root PTE levels being higher than other tissues. Elemental composition showed high primary nutrients (e.g., potassium, phosphorus), meeting EU requirements for organic soil improvers (EU Regulation 2019/1009). Whole-plant WH water extracts had high conductivity (≥ 6.98 mS/cm), nutrient and PTE concentrations, and caused adverse effects on all aquatic species. No clear toxicity ranking emerged, though Bico and Pateira extracts were least toxic, and Sorraia extract most severe (algal inhibition, zooplankton mortality, zebrafish effects at 0.78 % dilution). The findings indicate that WH biomass incorporation into soils should be considered on a site-specific basis, owing to variations in PTEs accumulation across locations, requiring contaminant screening and regulatory guidance before large-scale use. The results evidenced multispecies, multi-endpoint ecotoxicity that might justify the need for dilution strategies and controlled application rates of WH biomass on soils to minimize putative downstream impacts.
“The real life is to be with other people”: A social lens on immigrant integration through outdoor recreation
No full textThis article explores the role of domestic tourism, specifically outdoor recreational sports and events, in fostering immigrant integration, with a focus on Jämtland County in northern Sweden. While friluftsliv (outdoor recreation) holds a central place in Swedish leisure and domestic tourism culture, immigrants are often underrepresented in such activities. Rather than framing this solely as a matter of cultural difference, we investigate how immigrants perceive outdoor engagement, the barriers they encounter, and how social connections shaped through social capital can offer empowering, integrative experiences. The study draws on in-depth interviews with thirty-four immigrants, adding new knowledge to how outdoor recreation intersects with social capital, social sustainability, and integration. Our analysis highlights three key themes: belonging to outdoors, barriers to participation, and the role of sports and events in shaping social connections. We argue that outdoor engagement can support integration and enhance social sustainability, offering insights into both theory and inclusive practice in domestic tourism and recreation planning
Cutting peaks and costs : Techno-economic design guidelines for solar PVT and GSHP in land-constrained multi-family buildings
No full textThis study conducts a detailed techno-economic analysis of photovoltaic-thermal (PVT) collectors integrated with ground-source heat pumps (GSHPs) for land-constrained multi-family buildings in cold climates. Using dynamic TRNSYS simulations, the system is designed around an undersized borehole field and incorporates realistic electricity pricing models, including dynamic spot prices and capacity-based tariffs, and peak demand considerations. A stepwise analysis evaluates five PVT absorber types, array sizes, layouts, and control strategies. The most cost-effective design combines 60 m2 of unglazed finned collectors, pre-borehole layout, and 80 l/h-m2 fixed flow, achieving a seasonal performance factor above 2.7 and a minimum total life-cycle cost (TLCC) of €451 k€. Among all design variables, array size has the greatest impact on system performance and cost, with flow rate being the next most critical factor. Relative to a stand-alone GSHP, the hybrid system lowers peak electric load by 10 % and reduces total life-cycle cost by 4–23 % when benchmarked against alternative heating configurations including district heating, air-source heat pump, and PV-assisted GSHP. Scenario analyses show that electricity pricing structure and volatility significantly influence optimal collector sizing, with higher electricity prices favoring larger PVT array sizes. The results provide actionable design guidelines for researchers and practitioners seeking to improve performance and cost-effectiveness of heat pump systems, and to support their broader deployment in space- and grid-constrained urban environments.QC 20251217</p
Evaluating the Quality of GenAI Applications in Software Engineering : A Multi-case Study
No full textContext: Generative AI (GenAI) is increasingly adopted in software development for tasks such as document generation, data analysis, and code generation.However, evaluating the quality of GenAI applications becomes challenging, as traditional quality measurements may not be fully applicable. Objective: In this study, we explore how practitioners evaluate the quality of GenAI applications and investigate quality evaluation techniques. Method: We conducted a multi-case study in three industrial projects from software development companies.We examined four GenAI application domains: document generation, data analysis and insight generation, customer service, and code generation.Data were collected through three workshops and 23 semi-structured interviews with industrial practitioners. Results: We identified fourteen GenAI use cases and 28 metrics currently used to evaluate the quality of GenAI applications' outputs.We synthesized the identified metrics' usage patterns and challenges based on the collected data. Conclusions: This study presents practical insights into using metrics to measure GenAI-based system qualities in real industrial settings.Our findings indicate that practitioners use custom-built and context‑specific metrics; combining these with academic metrics can strengthen GenAI system quality evaluation
Vaccine protection against COVID-19 mortality in relation to time since last booster dose among nursing home residents in Sweden : A case-control study over 35 months
No full textBackground: The implementation of COVID-19 vaccination among older persons at nursing homes has lowered the infection-associated mortality considerably, but emerging virus variants and decline in vaccine-induced immunity over time necessitate examination of future booster dosing strategies. The overall aim of this study was to assess vaccine protection against COVID-19 mortality in relation to time elapsed since the last booster dose. Methods: All older persons living in nursing homes in Sweden at any time point December 27th, 2020 - December 4th, 2023 were included. For each case (5256 COVID-19 and 85,745 all-cause deaths), up to 10 controls were sampled randomly from this population, matched with respect to birth year, sex and county. The matched case-control sets were analyzed for vaccination history with conditional logistic regression, with further adjustment for co-morbidties and prior SARS-CoV-2 infection. Findings: Vaccination status (unvaccinated vs. vaccinated), ≥ 90 days since last vaccine dose, a co-morbidity score ≥ 2, and no previous SARS-CoV-2 infection were associated with death occurring within 30 days of a positive test. The odds ratio (OR) for COVID-19 death was 2.4 (95 % confidende interval [CI] 1.8–3.2) when contrasting at least 365 days with less than 90 days since the last vaccine dose. Interpretation: Waning vaccine protection was observed already 90 days after the last vaccine dose among older people living in nursing homes. The reported ORs imply that more than one third of all COVID-19 deaths could in the investigated setting have been possible to prevent by more frequent vaccine boosting during 2022–2023