| 1. |
- Dahlgren, Elin, et al.
(författare)
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Trophic transfer of naturally produced brominated aromatic compounds in a Baltic Sea food chain
- 2016
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 144, s. 1597-1604
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Tidskriftsartikel (refereegranskat)abstract
- Brominated aromatic compounds (BACs) are widely distributed in the marine environment. Some of these compounds are highly toxic, such as certain hydroxylated polybrominated diphenyl ethers (OH-PBDEs). In addition to anthropogenic emissions through use of BACs as e.g. flame retardants, BACs are natural products formed by marine organisms such as algae, sponges, and cyanobacteria. Little is known of the transfer of BACs from natural producers and further up in the trophic food chain. In this study it was observed that total sum of methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and OH-PBDEs increased in concentration from the filamentous red alga Ceramium tenuicorne, via Gammarus sp. and three-spined stickleback (Gasterosteus aculeatus) to perch (Perca fluviatilis). The MeO-PBDEs, which were expected to bioaccumulate, increased in concentration accordingly up to perch, where the levels suddenly dropped dramatically. The opposite pattern was observed for OH-PBDEs, where the concentration exhibited a general trend of decline up the food web, but increased in perch, indicating metabolic demethylation of MeO-PBDEs. Debromination was also indicated to occur when progressing through the food chain resulting in high levels of tetra-brominated MeO-PBDE and OH-PBDE congeners in fish, while some penta- and hexa-brominated congeners were observed to be the dominant products in the alga. As it has been shown that OH-PBDEs are potent disruptors of oxidative phosphorylation and that mixtures of different congener may act synergistically in terms of this toxic mode of action, the high levels of OH-PBDEs detected in perch in this study warrants further investigation into potential effects of these compounds on Baltic wildlife, and monitoring of their levels.
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| 2. |
- Abrandt Dahlgren, Madeleine, 1956-, et al.
(författare)
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Video as a Tool for Researching Simulation Practices
- 2019
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Ingår i: Interprofessional Simulation in Health Care. Abrandt Dahlgren M., Rystedt H., Felländer-Tsai L., Nyström S. (red.). - Cham : Springer. - 2210-5549 .- 2210-5557. - 9783030195427 - 9783030195410 ; , s. 31-55
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Bokkapitel (refereegranskat)abstract
- This chapter provides examples of how arrangements for collection and analyses of video data were organized across different sites. The common approach to data collection builds on established methods for recording of audiovisual materials in the social sciences with a focus on interaction and learning. The chapter describes how arrangements for data collection across different sites were organised, and how video analysis can be used as a method for collaborative analysis of practices. One approach is entitled purposeful approach to collaborative data analysis. A second approach draws on video-based studies of situated action, and a third approach of analysis is the use of qualitatively different readings of the same data. One does not replace the other, but rather draws out different features.
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| 3. |
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| 4. |
- Boalt, Elin, et al.
(författare)
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Cadmium, lead, and mercury concentrations in whole-fish, liver, and muscle of herring (Clupea harengus) and perch (Perca fluviatilis)
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Monitoring of metal concentrations in fish is commonly conducted using samples of fish liver or muscle. This becomes problematic when these values are used for environmental status evaluations regarding chemical pollution, as many of the thresholds evaluating environmental status are designed to evaluate concentrations in whole-fish.In this study, concentrations of cadmium, lead, and mercury in herring and perch are compared between liver, muscle, and whole-fish. The aim is to create conversion factors that can be used to convert metal concentrations between tissues and organs.Mercury and cadmium were detected in all analyzed organs and tissues, whereas lead concentrations were below the level of quantification for most muscle and liver samples. In general, there was a strong relationship between liver and muscle concentrations and concentrations in whole-fish, indicating that creation of conversion factors between tissues and organs is suitable.The resulting conversion factor between whole-fish and liver concentrations for cadmium was 0.1 and 0.16 for herring and perch, respectively. The conversion factor between whole-fish and liver concentrations for mercury was 0.52 and 1.66 for herring and perch, respectively, while for whole-fish and muscle concentrations for mercury, the conversion factor was 0.86 and 0.74 for herring and perch. As there was no significant relationship between liver and whole-fish concentrations for lead, a conversion is not appropriate. Conversion factors levels differed significantly between herring and perch, indicating that species-specific conversion factors are necessary.
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| 5. |
- Borchert, Erik, et al.
(författare)
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Deciphering a Marine Bone-Degrading Microbiome Reveals a Complex Community Effort
- 2021
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Ingår i: mSystems. - 2379-5077 .- 2379-5077. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- The marine bone biome is a complex assemblage of macro- and microor- ganisms; however, the enzymatic repertoire to access bone-derived nutrients remains unknown. The bone matrix is a composite material made up mainly of organic colla- gen and inorganic hydroxyapatite. We conducted field experiments to study microbial assemblages that can use organic bone components as nutrient source. Bovine and turkey bones were deposited at 69 m depth in a Norwegian fjord (Byfjorden, Bergen). Metagenomic sequence analysis was used to assess the functional potential of micro- bial assemblages from bone surface and the bone-eating worm Osedax mucofloris, which is a frequent colonizer of whale falls and known to degrade bone. The bone microbiome displayed a surprising taxonomic diversity revealed by the examination of 59 high-quality metagenome-assembled genomes from at least 23 bacterial families. Over 700 genes encoding enzymes from 12 relevant enzymatic families pertaining to collagenases, peptidases, and glycosidases putatively involved in bone degradation were identified. Metagenome-assembled genomes (MAGs) of the class Bacteroidia con- tained the most diverse gene repertoires. We postulate that demineralization of inor- ganic bone components is achieved by a timely succession of a closed sulfur biogeo- chemical cycle between sulfur-oxidizing and sulfur-reducing bacteria, causing a drop in pH and subsequent enzymatic processing of organic components in the bone sur- face communities. An unusually large and novel collagen utilization gene cluster was retrieved from one genome belonging to the gammaproteobacterial genus Colwellia. IMPORTANCE Bones are an underexploited, yet potentially profitable feedstock for biotechnological advances and value chains, due to the sheer amounts of residues produced by the modern meat and poultry processing industry. In this metagenomic study, we decipher the microbial pathways and enzymes that we postulate to be involved in bone degradation in the marine environment. We here demonstrate the interplay between different bacterial community members, each supplying different enzymatic functions with the potential to cover an array of reactions relating to the degradation of bone matrix components. We identify and describe a novel gene cluster for collagen utilization, which is a key function in this unique environment. We propose that the interplay between the different microbial taxa is necessary to achieve the complex task of bone degradation in the marine environment.
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| 6. |
- Bryhn, Andreas, et al.
(författare)
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Kunskapsunderlag om möjliga icke-torskfiskerelaterade åtgärder för att torskbestånd ska bevaras och återhämta sig i svenska vatten
- 2020
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Rapport (refereegranskat)abstract
- Torsk (Gadus morhua) är en viktig art för marina ekosystem i Sverige, där den har en strukturerande och reglerande funktion i relation till andra arter. Torsken har under historiens gång även spelat en viktig roll för samhället i Sverige inom dess nuvarande gränsers område (Bohuslän har t.ex. inte alltid tillhört Sverige), som en målart för fiske. Samtliga torskbestånd som återfinns i havsområdena runt Sverige har nu dålig status och det internationella havsforskningsrådet ICES rekommenderar låg eller ingen fångst, beroende på bestånd. Utöver riktat fiske påverkas dock torsken av en rad andra faktorer som exempelvis bifångster i annat fiske, syrebrist, klimatförändringar, predatorer, parasiter, bottenpåverkan av trålning, förlust av uppväxtmiljöer, födobrist, tiaminbrist och giftiga ämnen. Denna rapport diskuterar möjligheter att skydda och bevara torsken på sätt som kan komplettera begränsningar i det riktade torskfisket. Torskens situation är komplex och rapporten är därför skriven utifrån ett ekosystemperspektiv för att möjliggöra en bredare ansats i förvaltningen av torskbestånd i svenska vatten, där alla relevanta påverkansfaktorer bör beaktas. Det bör poängteras att denna rapport inte har gjort någon ny utredning av påverkansfaktorernas effekter, utan har istället gjort en litteratursammanställning och en kvalitativ analys. Vi har ändå valt att lyfta fram vissa åtgärder som särskilt potentiellt betydelsefulla - en samlad kvalitativ expertbedömning som rangordnar olika åtgärders effektivitet för återuppbyggnad per bestånd, se avsnitt 6 i rapporten.
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| 7. |
- Bryhn, Andreas, et al.
(författare)
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Which factors can affect the productivity and dynamics of cod stocks in the Baltic Sea, Kattegat and Skagerrak?
- 2022
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Ingår i: Ocean and Coastal Management. - : Elsevier BV. - 0964-5691 .- 1873-524X. ; 223
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Forskningsöversikt (refereegranskat)abstract
- Stocks of Atlantic cod (Gadus morhua) in the Baltic Sea, Kattegat and Skagerrak (N. Europe) have been strongly exploited for decades bringing them into an enduringly depleted status. Scientific cod stock related advice for targeted and mixed fisheries is provided on an annual basis by the International Council for Exploration of the Sea. This advice forms a basis for ministerial decisions on, e.g., the total allowable catch and management plans. Despite measures to reduce fishing-induced mortality of cod, such as catch and effort restrictions, increased gear selectivity, closed areas and seasons, clear signs of recovery are yet to be seen. Thus, traditional advice for the management of these stocks may have to be complemented by advice on supporting measures focusing on other pressures hampering the recovery of cod. The present study elaborates on potential supportive measures for cod stock recovery in the Baltic Sea, Kattegat, and Skagerrak (including local populations where applicable), based on current knowledge. The list of measures presented here is the outcome of in-depth discussions on the state-of-the-art knowledge, among cod experts and further with stakeholders with the aim to follow principles of ecosystem-based fisheries management. Following the identification of different pressures on and prerequisites for the separate stocks, the listed measures differ between stocks and include cod bycatch mortality reduction, alterations in fisheries affecting food sources for cod, restocking, protection of juvenile habitats, and reduced predation. The literature review and the list of measures are intended to provide decision-support for managers and policymakers aiming to provide conditions for the cod stocks to recover.
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| 8. |
- Dahlgren, Anna, et al.
(författare)
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Intensive longitudinal study of newly graduated nurses' quick returns and self-rated stress
- 2021
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Ingår i: Scandinavian Journal of Work, Environment and Health. - : Scandinavian Journal of Work, Environment and Health. - 0355-3140 .- 1795-990X. ; 47:5, s. 404-407
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Tidskriftsartikel (refereegranskat)abstract
- Objective Little is known about the relationship between quick returns (QR) - shift combinations that result in inter-shift rest periods <11 hours) and stress. The current study examined whether variations in the frequency of QR, both between and within individuals, were associated with changes in self-rated stress.Methods A questionnaire was sent weekly to newly graduated nurses during the first 12 weeks of work. Stress was measured with four items from the Stress-Energy Questionnaire on a scale from 1 not at all to 5 very much [mean 2.65, standard deviation (SD) 1.08]. Shifts worked in the past week were reported and QR were identified by evening-morning shift combinations (mean 0.98, SD 0.90 per week). In total, 350 persons were included in the analysis (3556 observations). Data were analyzed with a multilevel residual dynamic structural equation model (RDSEM) using Bayesian estimation procedures.Results There was no between-person effect of QR on stress averaged across measurement occasions (0.181, 95% CI -0.060-0.415). However, there was a small within-person effect of QR (0.031, 95% CI 0.001-0.062), meaning that more QR during a given week, compared to that person's average, was associated with an increase in their level of stress during that week.Conclusions Nurses were likely to report increased stress during weeks in which they worked more QR. Intervention studies are needed to determine whether the relationship is causal.
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| 9. |
- Dahlgren, Elin, et al.
(författare)
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Algtoxiner i Östersjön: en syntes
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Ett flertal fiskarter i Östersjön uppvisar idag en ökande hälsoproblematik. Huruvida exponering för naturligt producerade, toxiska substanser från alger och bakterier är kopplad till försämrad fiskhälsa är oklart. Denna syntes har som syfte att verka som en översikt av algtoxiner som kan vara av särskilt intresse för påverkan på hälsa hos fisk i Östersjön. Vidare undersöks eventuella kopplingar mellan data från den nationella miljöövervakningen som kan indikera förekomst och utbredning av algtoxiner samt eventuell påverkan på fiskhälsa. I Östersjön är det framförallt fintrådiga alger och cyanobakterier som producerar toxiska substanser vilkas förekomst dokumenterats i fisk och exponering kan förväntas leda till allvarliga effekter. De grupper av toxin som inkluderas i denna syntes är halogenerade organiska föreningar, cyanotoxiner, ichthytoxin, okadasyra och saixotoxin. Tillgång på data gällande algtoxiner, insamlat inom den nationella miljöövervakningen, är generellt sett låg. Befintliga tidsserier saknar kontinuitet. Forskningsmässigt är däremot kunskapsläget högre vilket medger goda möjligheter till att identifiera kunskapsluckor och behov inom miljöövervakningen. Brist på data begränsar dock möjligheten att genomföra analyser av tidsserier för att etablera eventuella samband mellan fiskhälsovariabler och halter av algtoxiner eller förekomst/produktion av sådana. Trots detta identifieras i denna syntes en samvariation mellan halter av bromerade algtoxin OH-PBDE47/68 och fiskhälsovariabler som indikerar påverkan på fiskarnas kondition och immunförsvar. Säsongsvariation gällande förekomst och intensitet av algtoxiner är en försvårande omständighet som påverkar möjligheterna till att använda biologiskt material som samlas inom ramen för löpande nationell miljögiftsövervakning. För retrospektiva analyser av algtoxiner har abborre från Kvädöfjäden insamlade inom den integrerade kustfiskövervakningen identifierats som en lämplig matris. Eftersom dessa fiskar analyseras för hälsoparametrar finns goda förutsättningar för individuella analyser av algtoxiner. Abborre är dessutom särskilt lämplig för analys av algtoxiner eftersom den exponeras för substanser från kustlevande fintrådiga alger såväl som cyanobakterier och andra mikroalger. Strömming är på grund av sitt pelagiala levnadssätt med begränsad exponering i kombination med sen insamlingsperiod inom miljöövervakningen, ej en lämplig matris för undersökning av exponering och effekter av de algtoxiner som inkluderats i denna undersökning.
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| 10. |
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