| 1. |
- Aguilera, Anabella, et al.
(författare)
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Ecophysiological analysis reveals distinct environmental preferences in closely related Baltic Sea picocyanobacteria
- 2023
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Ingår i: Environmental Microbiology. - Chichester : John Wiley & Sons. - 1462-2912 .- 1462-2920. ; 25:9, s. 1674-1695
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Tidskriftsartikel (refereegranskat)abstract
- Cluster 5 picocyanobacteria significantly contribute to primary productivity in aquatic ecosystems. Estuarine populations are highly diverse and consist of many co-occurring strains, but their physiology remains largely understudied. In this study, we characterized 17 novel estuarine picocyanobacterial strains. Phylogenetic analysis of the 16S rRNA and pigment genes (cpcBandcpeBA) uncovered multiple estuarine and freshwater-related clusters and pigment types. Assays with five representative strains (three phycocyanin rich and two phycoerythrin rich) under temperature (10–30°C), light(10–190 μmol photons m-2s-1), and salinity (2–14 PSU) gradients revealed distinct growth optima and tolerance, indicating that genetic variability was accompanied by physiological diversity. Adaptability to environmental conditions was associated with differential pigment content and photosynthetic performance. Amplicon sequence variants at a coastal and an offshore station linked population dynamics with phylogenetic clusters, supporting that strains isolated in this study represent key ecotypes within the Baltic Sea picocyanobacterial community. The functional diversity found within strains with the same pigment type suggests that understanding estuarine picocyanobacterial ecology requires analysis beyond the phycocyanin and phycoerythrin divide. This new knowledge of the environmental preferences in estuarine picocyanobacteria is important for understanding and evaluating productivity in current and future ecosystems.
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| 2. |
- Alegria Zufia, Javier, Ph.D. 1992-, et al.
(författare)
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Seasonal dynamics in picocyanobacterial abundance and clade composition at coastal and offshore stations in the Baltic Sea
- 2022
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Ingår i: Scientific Reports. - London : Nature Publishing Group. - 2045-2322. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Picocyanobacteria (< 2 um in diameter) are significant contributors to total phytoplankton biomass. Due to the high diversity within this group, their seasonal dynamics and relationship with environmental parameters, especially in brackish waters, are largely unknown. In this study, the abundance and community composition of phycoerythrin rich picocyanobacteria (PE-SYN) and phycocyanin rich picocyanobacteria (PC-SYN) were monitored at a coastal (K-station) and at an offshore station (LMO; similar to 10 km from land) in the Baltic Sea over three years (2018-2020). Cell abundances of picocyanobacteria correlated positively to temperature and negatively to nitrate (NO3) concentration. While PE-SYN abundance correlated to the presence of nitrogen fixers, PC-SYN abundance was linked to stratification/shallow waters. The picocyanobacterial targeted amplicon sequencing revealed an unprecedented diversity of 2169 picocyanobacterial amplicons sequence variants (ASVs). A unique assemblage of distinct picocyanobacterial clades across seasons was identified. Clade A/B dominated the picocyanobacterial community, except during summer when low NO3, high phosphate (PO4) concentrations and warm temperatures promoted S5.2 dominance. This study, providing multiyear data, links picocyanobacterial populations to environmental parameters. The difference in the response of the two functional groups and clades underscore the need for further high-resolution studies to understand their role in the ecosystem.
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| 3. |
- Alegria Zufia, Javier, et al.
(författare)
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Seasonality of Coastal Picophytoplankton Growth, Nutrient Limitation, and Biomass Contribution
- 2021
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Ingår i: Frontiers in Microbiology. - Lausanne : Frontiers Media S.A.. - 1664-302X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Picophytoplankton in the Baltic Sea includes the simplest unicellular cyanoprokaryotes (Synechococcus/Cyanobium) and photosynthetic picoeukaryotes (PPE). Picophytoplankton are thought to be a key component of the phytoplankton community, but their seasonal dynamics and relationships with nutrients and temperature are largely unknown. We monitored pico- and larger phytoplankton at a coastal site in Kalmar Sound (K-Station) weekly during 2018. Among the cyanoprokaryotes, phycoerythrin-rich picocyanobacteria (PE-rich) dominated in spring and summer while phycocyanin-rich picocyanobacteria (PC-rich) dominated during autumn. PE-rich and PC-rich abundances peaked during summer (1.1 x 10(5) and 2.0 x 10(5) cells mL(-1)) while PPE reached highest abundances in spring (1.1 x 10(5) cells mL(-1)). PPE was the main contributor to the total phytoplankton biomass (up to 73%). To assess nutrient limitation, bioassays with combinations of nitrogen (NO3 or NH4) and phosphorus additions were performed. PE-rich and PC-rich growth was mainly limited by nitrogen, with a preference for NH4 at >15 degrees C. The three groups had distinct seasonal dynamics and different temperature ranges: 10 degrees C and 17-19 degrees C for PE-rich, 13-16 degrees C for PC-rich and 11-15 degrees C for PPE. We conclude that picophytoplankton contribute significantly to the carbon cycle in the coastal Baltic Sea and underscore the importance of investigating populations to assess the consequences of the combination of high temperature and NH4 in a future climate.
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| 4. |
- Almgren Mason, Suzanne, 1963-
(författare)
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Life in the labyrinth : a reflexive exploration of research and politics
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is about exploring the politics within and around research. The starting point is a European project which ran from late 1997 to the end of 2000. It was called "Self-employment activities concerning women and minorities: their success or failure in relation to social citizenship policies" and had as its objective to provide the EU-Commission with recommendations for improved self-employment policies. Background material was complemented by interviews with "experts", but the main source of information was in the form of biographical interviews with the self-employed, or formerly self-employed, themselves. The qualitative method was used as a way of researching how individuals' background and experiences influenced their decision to become self-employed as well as their tendency to use labour market policies available for starting businesses. It was also a way to find out how those policies impacted on the individuals' lives. The consequent recommendations included a suggestion for broadening existing policies to comprise social aspects as well as financial allowances, and also the caution that self-employment was perhaps not the best solution to labour market and social exclusion.This latter doubt arose during project work, as did questions about methodology, the role of the researcher, and eventually about the politics that inform research. Only briefly touched upon in the project reports, these issues instead became the basis for the thesis. A reflexive rereading of the Final Report led to a critical examination of the political uses of concepts and categories, of how stereotypes affect research, and of the embeddedness in ethnocentric discourses of both research and researcher. The use of postcolonial and feminist theory, discourse analysis and a social constructionist perspective broadened the analytical possibilities and furthered understanding of the connections between politics and research. A conclusion is that a comprehensive change in the social order as well as in people's conscience is required to stem ethnic discrimination in society and the perpetuation of stereotypes and preconstructed categories in research.
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| 5. |
- Back, Jenny, 1984-, et al.
(författare)
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Psychosocial Predictors of Drop-Out from Organised Sport : A Prospective Study in Adolescent Soccer
- 2022
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Ingår i: International Journal of Environmental Research and Public Health. - Basel : MDPI. - 1661-7827 .- 1660-4601. ; 19:24
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Tidskriftsartikel (refereegranskat)abstract
- In recent years an increased drop-out rate in adolescents' soccer participation has been observed. Given the potentially adverse consequences of drop-out from soccer, more information about risk factors for drop-out is warranted. In the current study, Classification and Regression Tree (CRT) analysis was used to investigate demographic and motivational factors associated with an increased risk of drop-out from adolescent soccer. The results of this study indicate that older age, experiencing less autonomy support from the coach, less intrinsic motivation, being female, and lower socioeconomic status are factors associated with an increased risk of drop-out. An interpretation of the results of this study is that coaches play a central part in creating a sports context that facilitates motivation and continued soccer participation. Based on the findings of the current study we propose that soccer clubs implement theoretically informed coach education programs to help coaches adopt autonomy-supportive coaching strategies.
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| 6. |
- Bengtsson, Dennis, 1995-, et al.
(författare)
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The effects of interpersonal development programmes with sport coaches and parents on youth athlete outcomes : a systematic review and meta-analysis
- 2024
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Ingår i: Psychology of Sport And Exercise. - Amsterdam : Elsevier. - 1469-0292 .- 1878-5476. ; 70
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Forskningsöversikt (refereegranskat)abstract
- Interpersonal coach-and parent development programmes (CDP and PDP, respectively), have the goal to foster positive youth sport experiences through high-quality relations between coaches, parents, and youth athletes. In this paper we systematically reviewed the extant literature and estimate the overall magnitude of such programmes and how they can inform future interventions. Specifically, we aimed to: (a) conduct a systematic review on the literature of interpersonal CDPs and PDPs within the youth sport context; (b) examine the effects of such interventions on youth athlete outcomes via a meta-analysis. English written peer-reviewed publications and grey literature was identified through electronic search in databases and manual searches of reference lists. By utilising a priori criteria for inclusion and exclusion, 33 studies describing interpersonal CDPs, and PDPs were identified in the systematic review. Studies that presented required data for estimation of Hedge's g effect sizes were included in the meta-analysis (k = 27). By and large, the included studies used a quasi-experimental design (58%), sampled from team sports (79%), and reported several delivery methods (e.g., workshops, audio feedback, observations, peer group discussions) and outcome measures (e.g., anxiety, autonomous motivation, self-confidence). Some interventions were based on the same delivery protocols (e.g., Coach Effectiveness Training, Mastery Approach to Coaching) or theoretical frameworks (e.g., Achievement Goal Theory, Self-Determination Theory). The meta-analysis showed statistically significant small, and medium, effect sizes on a subsample of youth athlete outcomes (e.g., task-related climate, fun and enjoyment, anxiety), indicating that coach interpersonal skills can contribute to positive youth sport experiences. Theory-based interpersonal CDPs and PDPs are recommended to expand the knowledge in this field of research.
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| 7. |
- Bengtsson, Dennis, 1995-, et al.
(författare)
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The effects of interpersonal development programmes with sport coaches and parents on youth athlete outcomes : A systematic review and meta-analysis
- 2024
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Ingår i: Psychology of Sport And Exercise. - Amsterdam : Elsevier. - 1469-0292 .- 1878-5476. ; 70
-
Forskningsöversikt (refereegranskat)abstract
- Interpersonal coach-and parent development programmes (CDP and PDP, respectively), have the goal to foster positive youth sport experiences through high-quality relations between coaches, parents, and youth athletes. In this paper we systematically reviewed the extant literature and estimate the overall magnitude of such programmes and how they can inform future interventions. Specifically, we aimed to: (a) conduct a systematic review on the literature of interpersonal CDPs and PDPs within the youth sport context; (b) examine the effects of such interventions on youth athlete outcomes via a meta-analysis. English written peer-reviewed publications and grey literature was identified through electronic search in databases and manual searches of reference lists. By utilising a priori criteria for inclusion and exclusion, 33 studies describing interpersonal CDPs, and PDPs were identified in the systematic review. Studies that presented required data for estimation of Hedge's g effect sizes were included in the meta-analysis (k = 27). By and large, the included studies used a quasi-experimental design (58%), sampled from team sports (79%), and reported several delivery methods (e.g., workshops, audio feedback, observations, peer group discussions) and outcome measures (e.g., anxiety, autonomous motivation, self-confidence). Some interventions were based on the same delivery protocols (e.g., Coach Effectiveness Training, Mastery Approach to Coaching) or theoretical frameworks (e.g., Achievement Goal Theory, Self-Determination Theory). The meta-analysis showed statistically significant small, and medium, effect sizes on a subsample of youth athlete outcomes (e.g., task-related climate, fun and enjoyment, anxiety), indicating that coach interpersonal skills can contribute to positive youth sport experiences. Theory-based interpersonal CDPs and PDPs are recommended to expand the knowledge in this field of research. © 2023 The Authors
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| 8. |
- Berglund, Björn, et al.
(författare)
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Efficient removal of antibiotics in surface-flow constructed wetlands, with no observed impact on antibiotic resistance genes
- 2014
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Ingår i: Science of the Total Environment. - Amsterdam : Elsevier. - 0048-9697 .- 1879-1026. ; 476-477, s. 29-37
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Tidskriftsartikel (refereegranskat)abstract
- Recently, there have been growing concerns about pharmaceuticals including antibiotics as environmental contaminants. Antibiotics of concentrations commonly encountered in wastewater have been suggested to affect bacterial population dynamics and to promote dissemination of antibiotic resistance. Conventional wastewater treatment processes do not always adequately remove pharmaceuticals causing environmental dissemination of low levels of these compounds. Using constructed wetlands as an additional treatment step after sewage treatment plants have been proposed as a cheap alternative to increase reduction of wastewater contaminants, however this means that the natural microbial community of the wetlands becomes exposed to elevated levels of antibiotics. In this study, experimental surface-flow wetlands in Sweden were continuously exposed to antibiotics of concentrations commonly encountered in wastewater. The aim was to assess the antibiotic removal efficiency of constructed wetlands and to evaluate the impact of low levels of antibiotics on bacterial diversity, resistance development and expression in the wetland bacterial community. Antibiotic concentrations were measured using liquid chromatography-mass spectrometry and the effect on the bacterial diversity was assessed with 16S rRNA-based denaturing gradient gel electrophoresis. Real-time PCR was used to detect and quantify antibiotic resistance genes and integrons in the wetlands, during and after the exposure period. The results indicated that the antibiotic removal efficiency of constructed wetlands was comparable to conventional wastewater treatment schemes. Furthermore, short-term treatment of the constructed wetlands with environmentally relevant concentrations (i.e. 100-2000 ng x 1(-1)) of antibiotics did not significantly affect resistance gene concentrations, suggesting that surface-flow constructed wetlands are well-suited for wastewater treatment purposes. (c) 2014 Elsevier B.V. All rights reserved.
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| 9. |
- Brembilla, Christian, 1983-, et al.
(författare)
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Investigations of thermal parameters addressed to a building simulation model
- 2015
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Ingår i: Proceedings of BS2015. - India, Hyderabad : International Building Performance Simulation Association (IBPSA). ; , s. 2741-2748, s. 2741-2748
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Konferensbidrag (refereegranskat)abstract
- This paper shows the tolerance of thermal parameters addressed to a building simulation model in relation to the local control of the HVAC system. This work is suitable for a modeler that has to set up a building simulation model. The modeler has to know which parameter needs to be considered carefully and vice-versa which does not need deep investigations. Local differential sensitivity analysis of thermal parameters generates the uncertainty bands for the indoor air. The latter operation is repeated with P, PI and PID local control of the heating system. In conclusion, the local control of a room has a deterministic impact on the tolerance of thermal parameters.
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| 10. |
- Brembilla, Christian, 1983-, et al.
(författare)
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Paradoxes in understanding the Efficiency Factors of Space Heating
- 2019
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Ingår i: Energy Efficiency. - Dordrecht : Springer. - 1570-646X .- 1570-6478. ; 12:3, s. 777-786
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Tidskriftsartikel (refereegranskat)abstract
- Efficiency factors are here defined as the thermal energy performance indicators of the space heating. Until recently, the efficiency factors were assumed as one value for space heating located in any climate. This study addresses the problem of how the outdoor climate affects the efficiency factors of a space heating equipped with 1D model of hydronic floor heating. The findings show how the efficiency factors, computed with two numerical methods, are correlated with the solar radiation. This study highlights the paradoxes in understanding the results of efficiency factors analysis. This work suggests how to interpret and use the efficiency factors as a benchmark performance indicator.
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