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Nurses’ experiences of working in war-torn areas : a qualitative content analysis
No full textBakgrund: Genom historien har sjuksköterskor arbetat i krig och stor utveckling avsjuksköterskeprofessionen har skedd under den tiden. Beväpnade konflikter internationellt harsignifikant ökat och med behovet av sjuksköterskor krigsdrabbade områden. Tidigare forskninghar visat vilken påverkan krig har haft på sjuksköterskor och behovet av stöd behöver utvecklas.Syfte: Syftet med denna studie är att utforska sjuksköterskors upplevelser av att arbeta ikrigsdrabbade områden. Metod: En litteraturstudie med en kvalitativ induktiv ansats. Enlitteratursökning genomfördes i databaserna CINAHL och PubMed där 11 artiklar valdes förkvalitetsgranskning som sedan inkluderades i analysen av studien. Resultat: I resultatetframkommer olika teman av utmaningar som sjuksköterskor möter i arbetet i krigsdrabbadeområden, dessa teman är: Att hantera instabilitet, fara och begränsade resurser, att hantera svåraarbetsförhållanden, att lära sig av den hårda verkligheten, strategier för att hantera svårigheteroch motgångar, att hantera spänningen mellan sin personliga och professionella roll, att vårdakrigsskadade patienter från olika kulturer och att hantera orättvisa och moralisk stress.Slutsatser: Denna litteraturstudie kan ge viktig insikt för ökad förståelse av sjuksköterskorsupplevelser av att arbeta i krigsdrabbade områden vilket kan bidra till att utveckla specifikautbildningar samt stöd- och hjälpprogram för sjuksköterskor som har och/eller ska arbeta ikrigsdrabbade områden. Ytterligare forskning kan med fördel bedrivas angående sjuksköterskorsupplevelser och roller i krigsdrabbade områden för att öka förståelsen för krigets fysiska ochpsykiska konsekvenser på sjuksköterskor
Potential för organosolv lignin nanopartiklar som en hållbar flotations reagens : ett steg mot en gruvindustri med ett lågt koldioxidavtryck
No full textThe green transition is driving a steep increase in the demand for minerals, which has put the focus on more responsible and sustainable mining practices as there is a growing pressure on mining operations to minimise their environmental footprint, mitigate risks in neighbouring communities, and decrease the consumption of natural resources. In 2022, mineral froth flotation was used to recover 18 million tonnes of copper from copper ore, accounting for 80% of total copper mine output. The mineral froth flotation process can be made more sustainable through the use of bio-based and biodegradable flotation reagents. Currently, xanthates are used as collectors for the recovery of copper-bearing sulfide minerals from sulfide ores. However, xanthates are fossil-based and pose significant risks, particularly to aquatic life and ecosystems. Additionally, a significant part of xanthates is currently obtained from production sites in Asia, which can lead to supply dependency and delays, as evident during the global pandemic. The aim of this thesis was to develop an efficient, sustainable, and environmentally friendly mineral froth flotation process based on total or partial replacement of xanthates with bio-based, biodegradable, and low-carbon footprint organosolv lignin particles (OLP). The lignin was obtained through organosolv fractionation of residual forest biomass, i.e. spruce and birch. The particles were produced via solvent exchange method from the homogenized lignin solution. As a result, 4 different particle types were produced: birch nanoparticles (BN), birch microparticles (BM), spruce nanoparticles (SN), and spruce microparticles (SM). At first, the characterization and surface chemistry study of the OLP was carried out to deepen the understanding of interaction mechanism between the OLP and mineral surfaces. The lignin was characterized by gel permeation chromatography and nuclear magnetic resonance for its molecular size and content of functional groups. While morphology, surface charge and stability in dispersion of the particles was determined using scanning electron microscopy, ζ-potential, and Turbiscan. All 4 particles were spherical with the diameter around 100 nm for nanoparticles and 1μm for microparticles. The ζ-potential measurement showed the surface variation caused by the difference in size and content of functional groups. Spruce particles, SN and SM, had higher negative charge due to higher content of carboxylic and total phenolic groups. Under alkali conditions, the ζ-potential below -20mV for all particles, with the lowest at −55.1 mV for SM. Finaly, the interaction of OLP with mineral surfaces was examined using quartz crystal microbalance. While the attachment of all OLP was very rigid for both, chalcopyrite and pyrite surfaces, the affinity for attachment was notably greater in the case of pyrite compared to chalcopyrite. The OLP was tested in proof-of-concept study on three different ore samples, and improvements in the flotation performance was observed, including better selectivity and increased recovery. The further evaluation of the OLP as flotation reagent was conducted with copper ore samples. The flotation trials were carried out with 600 g of ore sample in laboratory flotation cell. Starting with the dosage study, the results were confirmed in rougher-cleaner flotation tests. However, the OLP could not be used as a sole collector, it was shown that significant part of xanthate in the flotation mix could be replaced by OLP resulting in improved copper recovery and selectivity. Additionally, a synergy was observed when the OLP and xanthate mixture was used as combined reagents performed better than each of them separately at the same dosage. The copper recovery was increased from 82.2% to 88.7% in a semi-pilot rougher flotation when 50% of xanthate was replaced by OLP compared to the xanthate alone. Significant depression of iron recovery was observed when the OLP was utilized, even in absence of lime. Thus, the OLP reagents eliminated the need for lime, which is required on an industrial scale. Further positive effect of OLP application was indicated recovery of other valuable elements in the concentrates, such as cobalt and molybdenum, while there was no increase in penalty elements. The amount of OLP needed was up to 10 g/ton of ore, which is very small amount, and it is roughly 10 times less compared to any other modifier used in such a process. Therefore, this thesis demonstrates the potential of OLP as flotation reagent. If implemented, the proposed flotation system would lead to better resource efficiency and lower environmental impact
Consumers' Understanding of Energy Labels: Perception of Eco-Design With Scale Range and Color-Coding
No full textEnergy labels help consumers understand the environmental impact of products. This drives consumer behavior. Knowing how label features are perceived can thus have important implications for design, policy, and management. Energy labels contain different design features that convey information about the range of available energy classes. Such contextual information can help people make informed comparisons. Across three behavioral experiments, we evaluate the perception of (EU's eco-design) energy labels based on their letter scale, color-coding, and information about the scale's range of energy classes. These three features had different influences on judgments of environmental friendliness. A letter scale that begins with the alphabet (A to G) helped participants tell apart energy classes linearly. But a scale that extends beyond the alphabet (A+++ to D) led to biased and skewed responses. Color-coding and information about the scale's range of energy classes provided important contextual information that made environmental judgments more discriminating and more stable. We demonstrate novel behavioral evidence on how such contextual information leads to better understanding of energy labels, with a discussion informed by range-frequency theory, the cue-utilization framework, and the heuristics and biases framework. Implications for policy and product marketing strategies with energy labels are discussed.Full text license: CC BY-NC-ND 4.0;Related dataset: 10.17605/OSF.IO/QXBER</p
Strength and heat development models including an aging activation energy for hardening Low-Carbon Concrete
No full textControlling early age thermal cracking in hardening Low-Carbon Concrete (LCC) casted in extreme weatherrequires precise modelling of its maturity, strength and heat development. The existing engineering-orientedmodels are useful for Portland Cement Concretes, but their accuracy for LCC is still unclear. Moreover, study-ing the dependence of LCC maturity parameters on whether mechanical or heat tests are implemented is also ofinterest. In response, this investigation proposed enhanced modelling techniques targeting a proper strength,heat, maturity, and cross-over effect assessment of LCC, including slag, limestone, superplasticizer, and air-entrainment. The models were calibrated using compressive, tensile, semi-adiabatic and isothermal calorim-etry tests. Moreover, a novel Activation Energy (Ea) function was proposed, accounting for its hydrationdependence, here referred to as aging. The proposed models represent improvements for the evaluation of LCC assuggested by comparison against classical approaches. For instance, they better capture the extended dormantperiod of LCC. Furthermore, the aging of the Ea was found imperative to accurately predict the heat developmentof LCC independently of the type of heat test selected for calibration. The models also predicted more severecross-over effect on the tensile than the compressive strength for low water-to-binder ratio LCC, which is relevantto decide on cracking risk mitigation measures. In general, the modelling techniques developed here evidencedgood performance for LCC and are worth of further exploration by researchers and practitioners. Their appli-cation will contribute to incentive wider use of LCC in infrastructure projects by providing more accurate pre-dictions of their cracking risk.Full text license: CC BY</p
Risk, flexibility, and investment in Fischer–Tropsch fuels: Insights from real options analysis
No full textThe transition to sustainable transportation fuels requires investment in emerging biomass-to-liquid production pathways under uncertain market and policy conditions. This study applies a real options analysis framework to evaluate the economic viability and timing of investments in biomass- and power-to-liquid pathways by identifying conditions where an investor should invest, defer, or abandon investments. The analysis is conducted for Sweden, reflected by its large biomass base and well-developed forest industry and ambitious defossilization policies. Results indicate that large price gaps between feedstock and produced fuels are not by themselves sufficient to trigger investment; in volatile markets, investors may still defer because the option to wait has economic value. Thus, even at identical price levels across scenarios, outcomes range from commitment to inaction depending on volatility. Moreover, when investments do occur, they are consistently deferred until the final year of the investment window. While modest subsidies may suffice under stable price conditions, volatile markets with high drifts require significantly greater support to counteract the incentive to defer investments. Electricity cost structures and carbon pricing must be targeted to support the transition toward electrified fuel production pathways. The insights from this study can inform the design of policy instruments that align investor incentives with global transition goals.Full text license: CC BY-NC-ND</p
Patients’ experiences of surviving a cardiac arrest in hospital : A literature review
No full textBakgrund: Ett plötsligt hjärtstopp kan drabba vem som helst, när som helst. I Sverige drabbas årligen cirka 2 500 personer av hjärtstopp inne på sjukhus, varav endast omkring 35 procent överlever. Att överleva ett hjärtstopp på sjukhus – i en miljö där vård finns omedelbart tillgänglig och där hjärt-lungräddning (HLR) påbörjas inom en minut. Syfte: Att beskriva patienters upplevelser av att överleva ett hjärtstopp på sjukhus. Metod: En kvalitativ litteraturstudie baserad på 8 vetenskapliga artiklar analyserades med innehållsanalys med induktiv ansats. Litteratursökning utfördes i databaserna CINAHL och PubMed. Resultat: Analysen resulterade i fyra kategorier: Att inse att man inte är odödlig och att livet är skört, Att hantera fysiska och kognitiva begränsningar, Att påverkas av brist på information och stöd av vården samt Att omprioritera och skapa ny mening med livet. Patienters upplevelser av hjärtstopp på sjukhus kan leda till minnesproblem, existentiella tankar, kognitiva förändringar, samt ett ökat behov av information. Patienterna hanterar situationen genom olika strategier och nya anpassningar till vardagen för att återfå kontroll över sin kropp. Slutsatser: Att överleva ett hjärtstopp på sjukhus är en livsomvälvande händelse. För sjuksköterskan kan studien ge en uppfattning om patientens tankar, känslor och behov efter att ha överlevt ett hjärtstopp på sjukhus, vilket kan bidra till att utveckla den personcentrerade vård som svensk sjukvård strävar efter. Nyckelord: Kvalitativ innehållsanalys, Litteraturstudie, Patient, Upplevelse, Hjärtstopp, Sjukhu
Beyond the Roar: Unravelling Audience Influence on Football Performance
No full textAccording to social facilitation theory the presence of others affects individuals’ sporting performance. Although based on extensive research, the theory has been scarcely tested in real sporting environments. However, audience restrictions due to the COVID-19 pandemic offered rare opportunities to examine effects of spectators’ presence and absence on football players’ performances. To exploit these opportunities, we collected data on individual players’ performances in the English Premier League (47,541 player performances in matches from the start of the 2017/18 season to 23rd January 2022) and Swedish Allsvenskan (25,249 performances in the 2018-2021 seasons). Results show that players’ performances were significantly better in the presence than in the absence of an audience (and the effect of audience presence was moderated by playing home or away) in the Premier League, but not Allsvenskan. Conversely, the effect of audience presence was moderated by average attendance and average stadium filling in and the relative skill of the opponent in Allsvenskan, but not the Premier League. The differences in results could be at least partly due to contextual differences between the two leagues, particularly in the average quality of players (which is higher in the Premier League). The study extends understanding of the complex nature of social facilitation in football, and highlights needs for further rigorous investigation of the mechanisms underlying the detected effects.Open access policy: "This journal provides instant open access based on the principle that free public access to research supports the global exchange of knowledge."</p
Ultrasound-driven formation of defects and radicals in contact-electro-catalysis: a DFT and AIMD investigation
No full textThis study reveals the critical chemical and physical roles of ultrasound in enhancing contact-electro-catalysis (CEC), using the methane (CH4) oxidation process as a model system. By integrating density functional theory (DFT), ab initio molecular dynamics (AIMD), and targeted experiments, we demonstrate for the first time that ultrasonic treatment significantly modifies the solid material’s (i.e. CEC catalyst) surface chemistry and morphology, leading to enhanced catalytic performance. FTIR and Raman spectroscopy analyses reveal distinct molecular-level changes in the tested solid material (i.e. fluorinated ethylene propylene (FEP)) following ultrasonication, specifically the formation of C–H bonds, aligning closely with theoretical spectra predictions. Additionally, ultrasound induces substantial physical alterations, tripling the surface roughness of FEP, and significantly elevating fluoride ion concentrations in the surrounding solution, indicating pronounced C–F bond cleavage. AIMD simulations further elucidate that ultrasound-generated radicals initiate homogenous catalytic pathways by cleaving C–H bonds in CH4, identifying this as a critical mechanistic step previously unclarified. Those induced structural defects in FEP could also simultaneously enhance heterogeneous catalytic activity. Our findings establish a comprehensive mechanistic framework that resolves prior ambiguities in ultrasound-assisted CEC processes, offering robust theoretical and experimental foundations for advancing CEC catalytic efficiency and guiding future CEC catalyst development.Validerad;2025;Nivå 2;2025-11-25 (u5);Full text license: CC BY 4.0;Funder: U.S. National Science Foundation (2422927)</p
Machine learning-driven investigation of environmental effects on dynamic behavior of railway noise barriers based on long-term field test
No full textThe passage of trains by railway noise barriers induces vibrations that may affect their fatigue performance and reduce their service life. However, long-term field monitoring of noise barriers under complex environmental and operation conditions remains rare. This study develops an interpretable machine learning (ML) framework to investigate the aerodynamic pressure and dynamic behaviors of noise barriers based on a nine-month long-term field monitoring campaign, yielding 12810 train runs over 105 valid days. Input variables include train type, speed, temperature, wind speed and direction, relative humidity, and air pressure, while the target responses cover train-induced aerodynamic pressure, stress near the base of the steel post, and displacement at the post top. Eight ML models, including four traditional and four ensemble algorithms, were used and systematically compared to evaluate their predictive capabilities and robustness. Ensemble models, particularly Gradient Boosting Decision Tree (GBDT), Light Gradient Boosting Machine (LGBM), and Extreme Gradient Boosting (XGBoost), achieved the best predictive performance, with R2 values exceeding 0.935 for stress and displacement, and 0.895 for pressure. XGBoost, offering a strong balance of predictive accuracy and computational efficiency, was selected for SHapley Additive exPlanations (SHAP)-based interpretability analysis to uncover the physical relationships behind the data-driven predictions. Results reveal that aerodynamic pressure was the most challenging response to predict, given its higher sensitivity to turbulent airflow and environmental fluctuations, whereas stress and displacement exhibited more stable and predictable patterns. SHAP analysis identified train speed and type as the most influential factors across all responses. While environmental factors had comparatively lower influence, temperature and instantaneous wind direction consistently showed higher importance among them. Relative humidity has a moderate effect on aerodynamic pressure but a minor impact on dynamic behavior. Air pressure and wind speed exhibit limited influence on all outputs. These findings highlight the novelty and effectiveness of integrating long-term monitoring data, ML methods, and SHAP-based interpretability, offering new insights into the dynamic behavior of railway noise barriers.Validerad;2025;Nivå 2;2025-12-01 (u5);Full text license: CC BY 4.0</p