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Modulating Whiteleg Shrimp (Penaeus vannamei) Health from the Inside out: Effects of Xylooligosaccharides from Salicornia ramosissima on Gut Metabolites and Microbial Community
No full textWhiteleg shrimp (Penaeus vannamei) is currently facing significant challenges related to severe disease outbreaks. As the importance of the host–microbiota relationship is being revealed, modulating this relationship has become a key strategy in disease management. Xylooligosaccharides (XOS)—short-chain sugar molecules—have been gaining attention for their potential health benefits in the prebiotics field. In this study, an XOS-rich extract from Salicornia ramosissima was incorporated into shrimp feeds to evaluate its impact on gut health, with the main focus on gut proteomics and microbiota. XOS were incorporated at 0.1% (XOS_0.1) and 1% (XOS_1) concentrations, and a 14-day feeding trial, followed by a bacterial challenge with Vibrio harveyi, was performed. The effects of XOS were evaluated by assessing zootechnical parameters, gene expression in the hepatopancreas, and gut microbiota and proteome. The results showed no significant differences in zootechnical parameters and gene expression after the 14-day trial between animals fed XOS diets and control. However, shrimp fed XOS_1 showed an increased diversity of the microbial communities in the gut when compared with those fed control. Also, known shrimp gut symbionts, such as Ruegeria, Leisingera, and Demequina, were significantly enriched in groups fed XOS after the feeding trial. XOS also modulated the regulation of proteins in the gut. Nevertheless, stressful conditions appear to alter the effects of XOS and the dynamics of gut bacteria. Further studies are warranted to understand the impacts of long-term inclusion of XOS extracts, especially on health-related parameters and disease resistance.Full text license: CC BY 4.0;Funder: FCT—Foundation for Science and Technology, I.P; BYT-FCT; CEEC</p
Semantic priming by task-irrelevant speech: category-level or item-level processing?
No full textRecent studies show that task-irrelevant speech affects subsequent behaviour. For instance, category-exemplar production is primed if those exemplars were previously auditory distractors that accompanied the presentation of visual digits for serial recall (Röer et al., Citation2017. Semantic priming by irrelevant speech. Psychonomic Bulletin & Review, 24(4), 1205–1210. https://doi.org/10.3758/s13423-016-1186-3). This study examines semantic organisation as a boundary condition for the semantic priming effect. In a between-participants design, sequences of auditory distractors were either semantically organised (eight exemplars from one category) or random (one exemplar from each of eight categories). Semantic priming was measured by comparing production probability of previously encountered words against a matched unencountered set. Prior research indicates that an unexpected categorical change in task-irrelevant speech disrupts performance, suggesting processing of shared categorical membership enhances semantic priming (e.g. Vachon et al., Citation2020. The automaticity of semantic processing revisited: Auditory distraction by a categorical deviation. Journal of Experimental Psychology: General, 149(7), 1360–1397. https://doi.org/10.1037/xge000071). Consistent with these findings, semantic priming was found when distractor words were semantically organised but was absent with randomly presented exemplars, offering insight into the semantic processing of background sound.Validerad;2025;Nivå 2;2025-11-12 (u8);Funder: Bial Foundation (201/ 20); German Academic Exchange Service (Deutscher Akademischer Austauschdienst) (91875827);Full text license: CC BY</p
Good girls? Ideal workers in online retail warehousing
No full textOnline retailing challenges the traditional male coding of warehousing. Based upon an ethnographic study at two Swedish online retail warehouses, this article seeks to understand why certain warehouses are numerically dominated by women. Employees express that men are less focused and more careless and easily bored than women, and hence not desirable for the goods-handling work. The warehouses extend to hard-working women driven by the shame of doing wrong, which reflect their orientation of bodies in the direction of enhancing production and profit. Workers attribute the positive social atmosphere at the warehouses to the numerical dominance of women and the small size of the workplaces. At the one hand, the constructed sameness of (women) workers through hard work and jargon contribute to a collective identity that strengthens them. At the other hand, the binary gendering of work and workers also contribute to making the ware houses into ‘straight spaces’ (Ahmed, 2006).Validerad;2025;Nivå 2;2025-02-12 (u2);Full text: CC BY License;This article has previously appeared as a manuscript in a thesis.</p
Conversion of Glass Waste into Zeolite A Adsorbent for Efficient Ammonium Ion Adsorption from Aqueous Solution: Kinetic and Isotherm Studies
No full textIn this study, a zeolitic adsorbent (AGW-ZA) was successfully developed from glass waste (GW)-derived aluminosilicates. The GW, serving as the starting material, underwent alkaline activation and hydrothermal treatment to yield the AGW-ZA adsorbent, which exhibited a surface area of 216.48 m2/g. The AGW-ZA demonstrated significantly higher ammonium (NH4+) ion adsorption (142.5 mg/g at 1000 mg/L) than pristine GW (80.0 mg/g). Optimal adsorption experimental parameters were identified (0.1 g dosage, pH = 7, and 10 h contact time) to determine the maximum NH4+ ions’ adsorption potential by adsorbents. Kinetic and isotherm models were applied to experimental data to describe the adsorption mechanisms. The pseudo-second-order model provided the best fit for both AGW-ZA and pristine GW, indicating that the adsorption process is followed by chemical interaction via ion exchange. Regarding isotherms, the Freundlich model was most suitable for AGW-ZA, signifying that NH4+ ions adsorbed on heterogeneous adsorbent surfaces by forming multilayers, while the Temkin model fit the pristine GW data, indicating the chemisorption nature with medium adsorbate–adsorbent interactions above the heterogeneous surface. This study explores the potential of transforming discarded GW into a high-performance zeolitic adsorbent for the mitigation of environmental pollution by removing NH4+ ions from wastewater while simultaneously addressing waste management challenges.Validerad;2025;Nivå 2;2025-04-07 (u8);Funder: National Natural Science Foundation of China (52020105011)Full text license: CC BY</p
Global coverage path planner in 2.5 dimensions for nonholonomic vehicles
No full textThis study presents a metaheuristic approach to coverage path planning for ground-based forest operations, focusing on minimizing path lengths for forest vehicles while considering terrain characteristics and vehicle parameters. Forest vehicles can usually tolerate higher pitch than roll angles, which makes them vulnerable to rollover. To mitigate that, this method utilizes a genetic algorithm to optimize the sequence of nodes, which are scattered over the site with equal spacing. The coverage path planner then calculates the Dubins path distance between every node in the fitness function, together with penalties for exceeding pitch, roll and soil moisture constraints for the vehicle. This ensures that the path planner tries to make the most traversable path as possible, while trying to minimize the driving distance. Two synthetic test sites resembling primitive challenging terrains, and one real site were utilized to theoretically evaluate the proposed method. The results show that aligning the node patterns with the critical slope headings, instead of having a straight pattern, had little effect on the path length. However, square grids can yield shorter paths across multiple runs, while triangular grids ensure consistent results in single runs. A two-hectare site took 43 minutes to calculate on average. This suggests that further development of the path planner could lead to significant improvements, enabling the management of sites larger than a few hundred nodes. However, the calculation time is justified for the reduced path length during deployment. The study presents a methodology that supports manual operators and establishes foundations for full autonomy.Validerad;2025;Nivå 2;2025-06-27 (u4);Full text license: CC BY 4.0;</p
Identifying quantum phase transitions with minimal prior knowledge by unsupervised learning
No full textIn this work, we proposed a novel approach for identifying quantum phase transitions in one-dimensional quantum many-body systems using AutoEncoder (AE), an unsupervised machine learning technique, with minimal prior knowledge. The training of the AEs is done with reduced density matrix (RDM) data obtained by Exact Diagonalization (ED) across the entire range of the driving parameter and thus no prior knowledge of the phase diagram is required. With this method, we successfully detect the phase transitions in a wide range of models with multiple phase transitions of different types, including the topological and the Berezinskii-Kosterlitz-Thouless transitions by tracking the changes in the reconstruction loss of the AE. The learned representation of the AE is used to characterize the physical phenomena underlying different quantum phases. Our methodology demonstrates a new approach to studying quantum phase transitions with minimal knowledge, small amount of needed data, and produces compressed representations of the quantum states.Validerad;2025;Nivå 2;2025-03-17 (u5);Full text license: CC BY 4.0;Funder: Research Grants Council ofHong Kong (CityU 11318722); National Natural Science Foundation of China (12204130); Shenzhen Start-Up Research Funds (HA11409065); City University of Hong Kong (9610438, 7005610, 9680320); HITSZ Start-Up Funds (X2022000);</p
Psychometric Validation of the Persian Version of the Lysholm Score
No full textBackground: The Lysholm Knee Score (LKS) is a widely utilized patient-reported outcome measure for knee injury patients, due to its robust psychometric properties. It has been translated and validated in several languages, but it has not been translated into Persian. Purpose: To perform psychometric validation and cultural adaptation for the Persian version of the LKS (P-LKS) in patients with anterior cruciate ligament tears. Study Design: Cohort study (diagnosis); Level of evidence, 3. Method: The LKS was translated into Persian using a forward-backward translation procedure. To assess the reliability and validity of the P-LKS, responses were gathered from 100 consecutive patients (mean age, 35 ± 13 years; 91 male and 9 female). These participants also fulfilled the Persian versions of the International Knee Documentation Committee Subjective Form (IKDC-SF) and the 36-Item Short Form Health Survey (SF-36). Construct validity was evaluated by correlating the scores from the P-LKS with those from the Persian IKDC-SF and SF-36. Reliability was determined by examining test-retest reliability and internal consistency. Additionally, floor and ceiling effects, as well as measurement errors, were assessed. The Bland-Altman method was utilized to evaluate absolute agreement. Results: Construct validity was strong, as >80% of the predetermined hypotheses regarding correlations between the P-LKS and other measures were verified. The P-LKS exhibited a high correlation with the Persian IKDC-SF (r = 0.92) and the physical component of the Persian SF-36 (r = 0.85). Bland-Altman analysis indicated no systematic bias among the test and retest phases. The test-retest reliability and internal consistency for the P-LKS were excellent (ICC = 0.97; Cronbach alpha = 0.88). Floor and ceiling effects for the overall score of the P-LKS were <15% (0% and 2%, respectively). The standard error of measurement was 1.04; the minimal detectable change at the individual level was 2.88, and at the group level, it was 0.29. Conclusion: The study demonstrated that the P-LKS successfully preserved the attributes of the original version. It can be regarded as a reliable tool for Persian-speaking patients with complete anterior cruciate ligament tear.Validerad;2025;Nivå 2;2025-04-15 (u8);Full text license: CC BY-NC-ND</p
Efficient Ruddlesden-popper (RP) perovskites as electron selective layers yielding over 20 % efficiency in MAPb(I1-xClx)3 based organic-inorganic perovskite solar cells: A DFT and SCAPS-1D investigations
No full textThe electron transport layer (ETL) is linchpin in perovskite solar cells (PSCs). It offers potent and discriminatory electron elicitation, minute resistivity, and lofty strength along with optimal device performance. In this study combined DFT and SCAPS-1D framework are used to investigate the optimized designs of CH3NH3Pb(I1-xClx)3 organic-inorganic perovskite-based solar cells. The analysis of structural stability, mechanical strength and optoelectronic traits was done by employing first-principle calculations with three different exchange-correlation functionals for A2SnO4(A = Sr, Ba) Ruddlesden-popper (RP) compounds. SCAPS-1D was used to analyze device performance by employing different ETLs in PSC architecture. The structural analysis reveal that Sr2SnO4 possesses a more stable structure in tetragonal phase with space group I4/mmm (139) than Ba2SnO4. Mechanical stability is corroborated through the reckoning of elastic constants, with Sr-based RP perovskite showing better mechanical properties as compared to Ba-based RP perovskite enunciating it auspicious for device fabrication. Electronic properties, analyzed through the band structure (BS) and density of state (DOS), confirm the semiconducting nature of both materials, with indirect band gap of 4.59 eV (Ba2SnO4) and 4.21 eV (Sr2SnO4). The optical analysis has stipulated that both materials are found to be good absorbers of ultraviolet (UV) radiation. An optimized device FTO/Sr2SnO4/MAPb(I1-xClx)3/Cu2O/Au is contemplated here with an open-circuit voltage (Voc) of 1.257 V, a short-circuit current (Jsc) of 23.06 mA/cm2, fill factors (FF) of 83.57 %, and a theoretical power conversion efficiency (PCE) of 24.25 %. Overall, our findings reveal that Sr2SnO4 RP material have promising and potential features as a novel ETL material for employment in organic-inorganic PSC as a source of renewable energy.Validerad;2025;Nivå 1;2025-04-15 (u5);Full text license: CC BY 4.0;</p
Brandrisker vid laddning av elcykelbatterier
No full text Elcyklar blir allt vanligare i samhället, vilket har lett till en ökning av elcykelbatterier och därmed relaterade brandincidenter. Detta examensarbete syftar till att undersöka riskerna och säkerheten kring laddning och hantering av elcykelbatterierna. Målet är att skapa en ökad förståelse för problematiken och utvärdera behovet av nationella riktlinjer för säker förvaring och laddning av dessa batterier. Arbetet har utförts genom en kombination av litteraturstudie och enkätundersökning, där data samlats in framförallt från räddningstjänster och myndighetsrapporter. Resultatet visar att antalet bränder kopplade till elcykelbatterier har ökat i takt med att användning av elcyklar ökat. En stor andel av respondenterna uttrycker ett behov av nationella riktlinjer som kan ge enhetliga rekommendationer för säker hantering och laddning av batterier. Studien lyfter också riskerna kopplade till litiumjonbatterierna, inklusive termisk rusning och utsläpp och svårigheterna att släcka, vilket gör dessa bränder särskilt farliga och svårhanterliga. Nuvarande släckningsmetoder, som ofta involverar stora mängder vatten, är effektiva men krävande. Alternativa släckmedel som Aqueous Vermiculite Dispersion (AVD) och F-500 diskuteras som potentiella lösningar. Arbetet identifierar ett tydligt behov av att förbättra säkerhetsarbetet kring elcykelbatterier. Som slutsats dras det att nationella riktlinjer rekommenderas för att förhindra bränder och öka säkerheten, samt att informationskampanjer genomförs för att öka allmänhetens medvetenhet. Genom att standardisera säkerhetsrutiner och förbättra utbildningen för räddningstjänster kan såväl person- som egendomsskador minimeras.
Staffan Storm - Choral Works
No full textThe three short movements in “Aspects of Snow” are united by the theme of snowy landscapes depicted in the poems and also share concentrated musical material. The piece was written in 2012 and premiered the same year by the Malmö Academy of Music Chamber Choir under the direction of Mats Paulsson. Else Lasker-Schüler (1869–1945) was one of the leading German writers in the decades after the turn of the century. She became famous for her expressionist poetry and her colorful performances. After the Nazis took power, she was persecuted and abused but managed to escape via Switzerland to Jerusalem, where she settled for the rest of her life. The short poem “Die Dämmerung holt die Sichel” can here surround the prose sketch “Nachtregen” (“The Night Rain”). The work is written for choir a cappella and solo viola, which functions as a wordless voice in the vocal folds. The work was composed in 2018 and is dedicated to Erik Westberg and his vocal ensemble. The suite “Seelenherbst” (“Autumn of the Soul”) for mixed choir and percussion was composed in 2021–22 and is based on a selection of poems by Luise Büchner (1821–1877). During her time, Büchner was a noted author of novels, short stories, and poetry. However, she probably became best known for her debate book “Die Frauen und ihr Beruf”, which was printed in several editions during her lifetime. She also worked to ensure that the works of her late older brother Georg Büchner, including “Wozzeck”, would be published. Luise Büchner’s poetry has a personal romantic-symbolist touch where nature, special places, and environments reflect and relate to people’s inner experiences and changing moods. Sometimes the picture expands with questions about the individual’s place in the universe. The chosen poems form a suite of five movements, where the two outer movements that frame the work depict a journey from winter to autumn, while the three middle movements are evening and night moods of different characters. This work is also written for and dedicated to Erik Westberg and his vocal ensemble. “Långt i försvunna tider” (“Far in Bygone Times”) takes its starting point from three songs by Wilhelm Stenhammar, “Stjärnöga”, “Flickan knyter i Johannesnatten” and “Vore jag ett litet barn”. I selected these songs because they were more open to new musical angles due to their close connection to the Swedish folk song. Stenhammar is here himself both freer in his use of harmony and in his part-writing, something I have underlined and partly reinforced. I have also placed the songs in surrounding wordless material as contrast and musical reflection, and here and there gaps also open up inside the songs when new material is used as contrast. Swedish Radio commissioned the work for the 150th anniversary of Wilhelm Stenhammar in 2021 and the Swedish Radio Choir premiered it under the direction of Erik Westberg. The album has been made possible through support from the Swedish Arts Council, the Kempe Foundation, and the Barbro Osher Pro Suecia Foundation. Validerad;2025;Nivå 1;2025-12-16 (U3)</p