| 1. |
- Ahlbeck Bergendahl, Ida, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2016 : Resursöversikt
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES).De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.Rapporten omfattar 41 fiskarter uppdelade i olika bestånd, samt sju skal- och blötdjursarter.Nytt för årets upplaga är kapitlet om ekosystemtjänster. Avsnittet beskriver de fördelar människan får genom ekosystemen, till exempel hur fisk och skaldjur kommer till nytta för människan genom föda, rekreation och biologisk mångfald. Nytt för i år är också att rapportens diagram och figurer anpassats för läsare med defekt färgseende.Översikten är utarbetad av SLU Aqua på uppdrag av Havs- och vattenmyndigheten.
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| 2. |
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| 3. |
- Ahlbeck Bergendahl, Ida, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2017 : Resursöversikt
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES).De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.Rapporten omfattar 41 fiskarter och sju skaldjursarter.Nytt för i år är att vi även beskriver fritidsfisket mer utförligt. Det fisket får allt större betydelse för utvecklingen av många av Sveriges bestånd av fisk- och skaldjur, till exempel sötvattens- och kustlevande arter som abborre, gädda, gös, lax, röding och öring, liksom marina arter som torsk och hummerÖversikten är utarbetad av SLU Aqua på uppdrag av Havs- och vattenmyndigheten.
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| 4. |
- Andersson, Erika, et al.
(författare)
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Expeditionsrapport kusttrålundersökningen 2020
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Den årliga kusttrålundersökningen längs den västsvenska skärgården sträcker sig från utsjöbanken Fladen i Kattegatt i söder till Singlefjorden vid norska gränsen i norr. Undersökningen har utförts årligen sedan 2001 med syftet är att inventera artsammansättningen och rekryteringen hos fisk i allmänhet samt förekomst av stor torsk i synnerhet. Kusttrålundersökningen tillför också grundläggande data avseende indikatorer för kustfiskarter inom ramen för arbetet med Havsmiljödirektivet.År 2020 utfördes kusttrålningen under 9 dagar mellan den 31 augusti och 10 september. Totalt trålades 33 stationer varav 8 låg i utsjön och 25 vid kusten.Endast en torsk över 40 cm fångades, dock var längdfördelningen av torsk över 20 cm per timme högre än vid föregående år, både vid kusten och i utsjön.
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| 5. |
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| 6. |
- Bengtsson, Lisa, 1981-, et al.
(författare)
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Impact of flow-dependent horizontal diffusion on resolved convectionin AROME.
- 2012
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Ingår i: Journal of Applied Meteorology and Climatology. - 1558-8424 .- 1558-8432. ; 51:1, s. 54-67
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Tidskriftsartikel (refereegranskat)abstract
- Horizontal diffusion in numerical weather prediction models is, in general, applied to reduce numerical noise at the smallest atmospheric scales. In convection-permittingmodels, with horizontal grid spacing on the order of 1–3 km, horizontal diffusion can improve themodel skill of physical parameters such as convective precipitation. For instance, studies using the convection-permitting Applications of Research to Operations at Mesoscale model (AROME) have shown an improvement in forecasts of large precipitation amounts when horizontal diffusion is applied to falling hydrometeors. The nonphysical nature of such a procedure is undesirable, however. Within the current AROME, horizontal diffusion is imposed using linear spectral horizontal diffusion on dynamicalmodel fields. This spectral diffusion is complemented by nonlinear, flow-dependent, horizontal diffusion applied on turbulent kinetic energy, cloud water, cloud ice, rain, snow, and graupel. In this study, nonlinear flowdependent diffusion is applied to the dynamical model fields rather than diffusing the already predicted falling hydrometeors. In particular, the characteristics of deep convection are investigated. Results indicate that, for the same amount of diffusive damping, the maximum convective updrafts remain strong for both the current and proposed methods of horizontal diffusion. Diffusing the falling hydrometeors is necessary to see a reduction in rain intensity, but amore physically justified solution can be obtained by increasing the amount of damping on the smallest atmospheric scales using the nonlinear, flow-dependent, diffusion scheme. In doing so, a reduction in vertical velocity was found, resulting in a reduction in maximum rain intensity.
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| 7. |
- Berggren, Peter, 1971-, et al.
(författare)
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Battlefield trauma care
- 2018
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Ingår i: Proceedings of the Human Factors and Ergonomics Society 62nd Annual Meeting. - : Sage Publications. ; , s. 634-638
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Konferensbidrag (refereegranskat)abstract
- Introduction: Rapid and structured medical care is important to increase wounded patients’ chances of survival in modern warfare. This requires a functioning medical chain. Aim: The aim of this study was to expand the knowledge of how the battlefield trauma care affects patient outcome in situations with a large number of casualties in the Swedish armed forces. Methods: An empirical study with a convergent parallel mixed methods design, which included observations and semi-structured interviews. Results: The results show that the trauma care performed at Role 1-units functioned well. The most prominent issue discovered was deficiency in transportation resources for medical evacuation throughout the entire medical chain. Conclusion: Despite that the trauma care performed at Role 1-units functions well, casualties are at risk for preventable complications or death. Improved transportation logistics are required to improve the medical capabilities of the Swedish armed forces.
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| 8. |
- Bergman, Filip, 1992-, et al.
(författare)
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A Critical Review of the Sustainability of Multi-Utility Tunnels for Colocation of Subsurface Infrastructure
- 2022
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Ingår i: Frontiers in Sustainable Cities. - : Frontiers Media S.A.. - 2624-9634. ; 4
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Forskningsöversikt (refereegranskat)abstract
- Multi-utility tunnel (MUT) have received increasing attention as an alternative method for installing subsurface infrastructure for the distribution of electricity, telecommunications, water, sewage and district heating. MUTs are described as a potentially more sustainable technology than conventional open-cut excavation (OCE), especially if the entire life cycle of these cable and pipe networks is taken into account. Based on an extensive review of the academic literature, this article aims to identify and critically examine claims made about the pros and cons of using MUT for the placement of subsurface infrastructure. Identified claims are mapped, and their validity and applicability assessed. These claims are then analyzed from a sustainability perspective, based on the three sustainability dimensions and a life cycle perspective. The results show that a variety of advantages and disadvantages of using MUTs for subsurface infrastructure are highlighted by the articles, but several of these are without any empirical support. When some form of empirical support is presented, it usually comes from case-specific analyses of MUTs, and the applicability in other MUT projects is seldom discussed. Economic performance is the sustainability dimension that has received the most attention, while environmental performance has not been analyzed in the reviewed literature, which is a major limitation of the current knowledge. In summary, the knowledge about the sustainability performance of using MUTs for subsurface infrastructure is still limited and incoherent. In order to increase the knowledge, this article points out the importance of new case studies, in which the sustainability consequences of using MUTs for subsurface infrastructure are mapped and evaluated by combining both quantitative and qualitative assessment methods.
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| 9. |
- Bergman, Filip, 1992-
(författare)
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Sustainability performance of multi-utility tunnels : Sustainability assessments for furthering knowledge and understanding
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The multi-utility tunnel has received increased attention as an alternative method for the installation of subsurface infrastructure for the distribution of electricity, water, sewage and district heating. In previous research, the multi-utility tunnel (MUT) has been described as a more sustainable technology compared to the conventionally used technique where the cables and pipes are placed with open-cut excavation (OCE), especially when the entire life cycle is taken into account. This thesis aims to contribute to an improved understanding of MUT's sustainability performance in relation to conventional installation using open-cut excavation. This is done by using literature study, interview study and quantitative sustainability assessments to gain an understanding of the current state of knowledge. Furthermore, this thesis also focuses on how knowledge can be deepened with the help of quantitative sustainability assessments and the challenges of conducting this type of assessment. This thesis shows that the state of knowledge regarding MUT's sustainability performance is low and scattered, with a lack of a holistic approach. Direct economic performance has gained the most attention, followed by indirect and social impact, and the environmental impact has so far barely been assessed. The sustainability performance depends to a large extent on the conditions of the specific case, and these should be considered when assessing the technology. Quantitative assessments have the potential to help deepen the knowledge of the sustainability implications of using MUT. The characteristics of MUT have some similarities with other types of physical infrastructure. Similarities are that the systems are long-lived, have project conditions that affect sustainability performance, and impact a broad spectrum of actors. One difference to typical infrastructure systems is that the owner and management structure of MUT is, by design, more complex as several types of utility systems are in use. The characteristics of MUT give some practical considerations that need to be addressed: data availability, including practitioners; detailed data; transparency; and flexibility. This thesis highlights the complexity of assessing MUT´s sustainability performance and advocates that future studies should have a learning-oriented approach so that the knowledge level can collectively and gradually improve over time rather than focusing on decision-oriented studies.
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| 10. |
- Björklund Svensson, Jonas, et al.
(författare)
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Double-bunches for two-color soft X-ray free-electron laser at the MAX IV Laboratory
- 2018
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Ingår i: Proceedings of FEL2017, Santa Fe, NM, USA. - 9783954501793 ; , s. 269-272
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The ability to generate two-color free-electron laser (FEL) radiation enables a wider range of user experiments than just single-color FEL radiation. There are different schemes for generating the two colors, the original being to use a single bunch and two sets of undulators with different K-parameters. An alternative scheme was recently shown, where two separate bunches in the same RF bucket are used for lasing at different wavelengths in a single set of undulators. We here investigate the feasibility of accelerating and compressing a double-bunch time structure generated in the photocathode electron gun for subsequent use in a soft X-ray FEL at the MAX IV Laboratory.
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| 11. |
- Björklund Svensson, Jonas, et al.
(författare)
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Driver-witness-bunches for plasma-wakefield acceleration at the MAX IV Linear Accelerator
- 2017
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Ingår i: IPAC 2017 - Proceedings of the 8th International Particle Accelerator Conference. - 9783954501823 ; , s. 1743-1746
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Beam-driven plasma-wakefield acceleration is an acceleration scheme promising accelerating fields of at least two to three orders of magnitude higher than in conventional radiofrequency accelerating structures. The scheme relies on using a charged particle bunch (driver) to drive a non-linear plasma wake, into which a second bunch (witness) can be injected at an appropriate distance behind the first, yielding a substantial energy gain of the witness bunch particles. This puts very special demands on the machine providing the particle beam. In this article, we use simulations to show that, if driver-witness-bunches can be generated in the photocathode electron gun, the MAX IV Linear Accelerator could be used for plasma-wakefield acceleration.
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| 12. |
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| 13. |
- Dzhigaev, Dmitry, et al.
(författare)
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Strain mapping inside an individual processed vertical nanowire transistor using scanning X-ray nanodiffraction
- 2020
-
Ingår i: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3372 .- 2040-3364. ; 12:27, s. 14487-14493
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Tidskriftsartikel (refereegranskat)abstract
- Semiconductor nanowires in wrapped, gate-all-around transistor geometry are highly favorable for future electronics. The advanced nanodevice processing results in strain due to the deposited dielectric and metal layers surrounding the nanowires, significantly affecting their performance. Therefore, non-destructive nanoscale characterization of complete devices is of utmost importance due to the small feature sizes and three-dimensional buried structure. Direct strain mapping inside heterostructured GaSb-InAs nanowire tunnel field-effect transistor embedded in dielectric HfO2, W metal gate layers, and an organic spacer is performed using fast scanning X-ray nanodiffraction. The effect of 10 nm W gate on a single embedded nanowire with segment diameters down to 40 nm is retrieved. The tensile strain values reach 0.26% in the p-type GaSb segment of the transistor. Supported by the finite element method simulation, we establish a connection between the Ar pressure used during the W layer deposition and the nanowire strain state. Thus, we can benchmark our models for further improvements in device engineering. Our study indicates, how the significant increase in X-ray brightness at 4th generation synchrotron, makes high-throughput measurements on realistic nanoelectronic devices viable.
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| 14. |
- Florin, Ann-Britt, et al.
(författare)
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First records of Conrad´s false mussel, Mytilopsis leucophaeata (Conrad, 1831) in the southern Bothnian Sea, Sweden, near a nuclear power plant
- 2013
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Ingår i: BioInvasions Records. - : Regional Euro-Asian Biological Invasions Centre Oy (REABIC). - 2242-1300. ; 2:4, s. 303-309
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Tidskriftsartikel (refereegranskat)abstract
- The invasive, biofouling, Conrad's false mussel Mytilopsis leucophaeata was first recorded in Sweden during spring 2011 in the cooling water system of the power plant of Forsmark in the southern Bothnian Sea. The cooling water discharge area offers a favourable environment for growth, survival, and reproduction of M. leucophaeata and may provide a stepping stone for further spread. We present three different studies in the area, revealing a rapid increase in mussels in the artificially heated area, with densities of the magnitude of thousands of individuals m-2, as well as mussels living in surrounding waters, indicating an on-going expansion in the region.
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| 15. |
- Florin, Ann-Britt, et al.
(författare)
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First records of Conrad’s false mussel, Mytilopsis leucophaeata (Conrad, 1831) in the southern Bothnian Sea, Sweden, near a nuclear power plant
- 2013
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Ingår i: BioInvasions Records. - : Regional Euro-Asian Biological Invasions Centre Oy (REABIC). - 2242-1300. ; 2, s. 303-309
-
Tidskriftsartikel (refereegranskat)abstract
- The invasive, biofouling, Conrad's false mussel Mytilopsis leucophaeata was first recorded in Sweden during spring 2011 in the cooling water system of the power plant of Forsmark in the southern Bothnian Sea. The cooling water discharge area offers a favourable environment for growth, survival, and reproduction of M. leucophaeata and may provide a stepping stone for further spread. We present three different studies in the area, revealing a rapid increase in mussels in the artificially heated area, with densities of the magnitude of thousands of individuals m-2, as well as mussels living in surrounding waters, indicating an on-going expansion in the region. Key words: cooling water; biofouling; invasive mussel
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| 16. |
- Holmerin, Isak, et al.
(författare)
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Benthic food web structures as an explanation for prolonged ecological half-life of Cs-137 in flatfish species in the Fukushima coastal area
- 2022
-
Ingår i: Journal of Environmental Radioactivity. - : Elsevier BV. - 0265-931X .- 1879-1700. ; 246
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Tidskriftsartikel (refereegranskat)abstract
- After the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP), Japan, in March 2011, Cs-137 in demersal fish had, between 2011 and 2015, a prolonged ecological half-life when compared to pelagic fish. Using stable isotope mixing models combined with gut content analysis and Cs-137 activity concentrations, this study investigated the hypothesis that an unexplored food web structure could be a contributing factor explaining the ecological half-life of Cs-137 in benthic flatfish. Benthic invertebrates and demersal fish species sampled in 2015 still showed Cs-137 activity concentrations higher than pre-accident. The mixing models of stable N and C isotopes and gut content analysis identified deposit, suspension and filter feeders to be the main flatfish food items in the benthos. There was a significant correlation between Cs-137 activity concentrations in specific flatfish species and benthos, and between Cs-137 activity concentrations in benthos and surface sediment. The results of this study partially explained the Cs-137 activity concentrations found in the analysed demersal fish, suggesting that the benthos can be a continuous source of Cs-137 for the demersal fish during this period of time. Extending monitoring programmes to include invertebrates that are not food species for humans would greatly improve our ability to understand the role of trophic transfer pathways and take appropriate management actions.
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| 17. |
- Håkanson, Ulf, et al.
(författare)
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Nano-aperture fabrication for single quantum dot spectroscopy
- 2003
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 14:6, s. 675-679
-
Tidskriftsartikel (refereegranskat)abstract
- We present a simple and controllable method for fabricating nano-apertures in a metal film using polystyrene nano-spheres as masks during the metal evaporation. We show how the processing conditions used during deposition of the spheres such as spin velocity, nano-sphere concentration and a reduction of the surface tension interplay and control the distribution of spheres. The fabrication method is ideal for luminescence studies by isolating individual nanometre-sized objects, which is exemplified by photoluminescence spectroscopy of single self-assembled Stranski-Krastanow quantum dots.
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| 18. |
- Johnsson, Filip, 1960, et al.
(författare)
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Fluidization regimes in boilers
- 1995
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Ingår i: Preprints of Fluidization VIII. ; , s. 129-136
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The fluid dynamics were studied in a fluidized bed boiler and in two laboratory fluidized beds under ambient conditions. The beds had different geometries but were all of a non-slugging type operated with Geldart Group B and D particles. The bed geometry was found to strongly influence the fluid dynamics of the bed.
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| 19. |
- Johnsson, Filip, 1960, et al.
(författare)
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Fluidization regimes in fluidized bed boilers
- 1992
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Ingår i: Proc of the 7th Engineering Foundation Conference on Fluidization. - 0939204479 ; 7, s. 471-478
-
Konferensbidrag (refereegranskat)abstract
- The fluidization regime of the bottom bed has been investigated in a circulating fluidized bed at ambient temperature. A few measurements have also been made in a 12 MWth CFB boiler at normal operation temperature. It was found that the bottom bed was of a bubbling type for all conditions studied.
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| 20. |
- Johnsson, Filip, 1960, et al.
(författare)
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Marginal Abatement Cost Curve of Industrial CO 2 Capture and Storage – A Swedish Case Study
- 2020
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Ingår i: Frontiers in Energy Research. - : Frontiers Media SA. - 2296-598X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Carbon capture and storage (CCS) is expected to play a key role to achieve deep emission cuts in the energy intensive industry sector. The implementation of carbon capture comes with a considerable investment cost and a significant effect on the plants operating cost, which both depend on site conditions, mainly due to differences in flue gas flow and composition and depending on the availability of excess heat that can be utilized to power the capture unit. In this study we map the costs required to install and operate amine-based post-combustion CO2 capture at all manufacturing plants in Sweden with annual emissions of 500 kt CO2 or more, of both fossil and of biogenic origin, of which there are 28 plants (including a petrochemical site, refineries, iron and steel plants, cement plants and pulp and paper mills). The work considers differences in the investment required as well as differences in potential for using excess heat to cover the steam demand of the capture process. We present the resulting total CO2 capture costs in the form of a marginal abatement cost curve (MACC) for the emission sources investigated. Cost estimations for a transport and storage system are also indicated. The MACC shows that CO2 capture applied to 28 industrial units capture CO2 emissions corresponding to more than 50% of Swedish total CO2 emissions (from all sectors) at a cost ranging from around 40 €/t CO2 to 110 €/t CO2, depending on emission source. Partial capture from the most suited sites may reduce capture cost and, thus, may serve as a low-cost option for introducing CCS. The cost for transport and storage will add some 25 to 40 €/t CO2, depending on location and type of transportation infrastructure.
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| 21. |
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| 22. |
- Larsson, Stefan, et al.
(författare)
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Indikatorrapportering för “Hållbart nyttjande av fisk- och skaldjursbestånd i kust och hav” : bedömningsåret 2022
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sedan 2018 har institutionen för akvatiska resurser (SLU Aqua), på uppdrag av Havs- och vattenmyndigheten, utformat en indikator med tillhörande för uppföljning av miljökvalitetsmålet ”Hav i balans samt levande kust och skärgård”. Indikatorn (Hållbart nyttjande av fisk- och skaldjursbestånd i kust och hav) fokuserar på en övergripande status för svenska fisk- och skaldjursbestånd längs kusterna och i haven. Bedömningen baseras på årliga analyser av enskilda fiskbestånds status i rapporten ”Fisk- och skaldjursbestånd i hav och sötvatten”, och anger om bestånden fiskas hållbart eller och ej. Bedömningar för indikatorn har utförts mellan åren 2015- 2022.I föreliggande rapport presenteras en bedömning av indikatorns status för året 2022. Eftersom bedömningarna av nationellt förvaltade fisk- och skaldjursbestånd under 2022 uppdaterats jämfört med tidigare år, innehåller denna rapport två bedömningar. Den ena utgår från den nya modifierade bedömningsmetodiken, och den andra som följer den äldre metodiken och därmed medger en jämförelse av indikatorns status över tid.Av de totalt 72 redovisade bestånden i rapporten "Fisk- och skaldjursbestånd i hav och sötvatten 2022” kunde en bedömning göras för 68 bestånd. Av dessa klassades 35 (48,6 %) som ”hållbart nyttjande”. Indikatorns status var högst i Bottenviken (62,5 % av bestånden klassades som ”hållbart nyttjande”), följt av Västerhavet (52,5 %), och Östersjön (43,5 %). Lägst andel bedömda bestånd klassade som ”hållbart nyttjande” fanns i Bottenhavet (36,4 %). En högre andel bestånd med så kallad analytisk beståndsuppskattning (MSY- konceptet) ger en högre tillförlitlighet i den sammantagna bedömningen av de bestånd som redovisas i indikatorn. Tillförlitligheten för klassningen 2022 är högst i Västerhavet där andelen bestånd bedömda enligt MSY- konceptet är 35%, följt av Östersjön (25%), Bottenhavet (17%) och Bottenviken (11%). Andelen av de totala officiella svenska kommersiella landningarna av fisk och skaldjur som indikatorn omfattar ligger över 99 %. Med utgångspunkt i den äldre metodiken har andelen hållbara bestånd sjunkit något under 2022 jämfört med 2021 (från 52,2 % 2021 till 48,6 % 2022), detta då antalet redovisade bestånd ökat från 69 till 72.I en jämförelse mellan bedömningarna baserade på den äldre och den nya modifierade bedömningsmetodiken ses endast små skillnader i indikatorns status. Antalet och andelen bestånd kategoriserade som ”hållbart nyttjande” under bedömningsåret 2022 var de samma för båda metoderna (35 st, 48,6%). Med den nya metoden kunde emellertid ett bestånd mer bedömas jämfört med den gamla metoden.
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| 23. |
- Larsson, Stefan, et al.
(författare)
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Indikatorrapportering för “Hållbart nyttjande av fisk- och skaldjursbestånd i kust och hav” : bedömningsåret 2023
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Institutionen för akvatiska resurser (SLU Aqua) har på uppdrag av Havs- och vattenmyndigheten, utformat en indikator, Hållbart nyttjande av fisk- och skaldjursbestånd i kust och hav, för uppföljning av miljökvalitetsmålet ”Hav i balans samt levande kust och skärgård”. Indikatorn visar den övergripande statusen för svenska fisk- och skaldjursbestånd längs kusterna och i haven, och baseras på de årliga analyserna av enskilda fiskbestånds status i rapporten ”Fisk- och skaldjursbestånd i hav och sötvatten”, vilken redovisas på webbportalen Fiskbarometern (SLU Aqua 2024). Indikatorn anger om bestånden fiskas hållbart eller ej, vilket i och med denna rapport nu har gjorts för åren 2015-2023. I denna rapport presenteras en bedömning av indikatorns status för året 2023. Metoden för bedömningarna av nationellt förvaltade fisk- och skaldjursbestånd uppdaterades under 2022, vilket har medfört att indikatorn över andelen hållbara bestånd inte längre är fullt jämförbar mellan samtliga år i tidsserien. I en jämförelse i indikatorrapporten för bedömningsåret 2022 mellan den äldre och den uppdaterade metoden var dock skillnaderna i indikatorns status generellt små. I föreliggande rapport baseras indikatorn på den nya metoden och omfattar således endast resultat för bedömningsåren 2022 och 2023. Av de totalt 76 redovisade kust- och havslevande bestånden i rapporten "Fisk- och skaldjursbestånd i hav och sötvatten 2023” kunde en bedömning göras för 67 bestånd. Av de 76 redovisade bestånden klassades 31 (40,8 %) som ”hållbart nyttjande”, vilket är lägre än i rapporten från 2022 då andelen var 48,6 % (35 av 72). Endast bedömningsåret 2019 har visat en lägre andel av hållbart nyttjade bestånd (39,7%) än bedömningsåret 2023. Indikatorns status var högst i Bottenviken och Västerhavet (44,4 % i respektive bedömningsenhet), följt av Östersjön (29,2 %). Lägst andel bedömda bestånd klassade som ”hållbart nyttjande” noterades för i Bottenhavet (7,7 %). Motsvarande för bedömningsåret 2022 för Bottenviken, Västerhavet, Östersjön och Bottenhavet var 55,5 %, 48, 8%, 41,2 %, respektive 33,3 %. Anledningen till att den övergripande statusen försämrats beror bland annat på att europeisk skrubbskädda under 2023 har bedömts som ”ej hållbart nyttjande”, både i Västerhavet och i Östersjön, till skillnad mot 2022 då den bedömdes som ”hållbart nyttjande”. Motsvarade gäller också för sill/strömming i Bottenhavet och Bottenviken, liksom för tunga i Östersjön och kolmule i Västerhavet. Vidare har torskbeståndet i Skagerrak och Nordsjön delats upp i tre nya torskbestånd vilka samtliga har bedömts som ”ej hållbart nyttjande”. Utöver dessa förändringar har några bestånd gått från ”hållbart nyttjande” eller ”ej hållbart nyttjande” till ”bedömning ej möjlig” (till exempel braxen och piggvar i Östersjön). En högre andel bestånd med så kallad analytisk beståndsuppskattning (MSY- konceptet) ger en högre tillförlitlighet i den sammantagna bedömningen av de bestånd som redovisas i indikatorn. Sammantaget för alla fyra bedömningsenheter 2023 var andelen bestånd med analytisk beståndsuppskattning 28%. Tillförlitligheten var högst i Västerhavet där andelen bestånd bedömda enligt MSY- konceptet är 38%, följt av Östersjön (25%), Bottenhavet (15%) och Bottenviken (11%). Andelen av de totala officiella svenska kommersiella landningarna av fisk och skaldjur som indikatorn omfattar ligger över 99 %.
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| 24. |
- Leder, Erica H, 1967, et al.
(författare)
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Post-glacial establishment of locally adapted fish populations over a steep salinity gradient
- 2021
-
Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 34:1, s. 138-56
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Tidskriftsartikel (refereegranskat)abstract
- Studies of colonization of new habitats that appear from rapidly changing environments are interesting and highly relevant to our understanding of divergence and speciation. Here, we analyse phenotypic and genetic variation involved in the successful establishment of a marine fish (sand goby,Pomatoschistus minutus) over a steep salinity drop from 35 PSU in the North Sea (NE Atlantic) to two PSU in the inner parts of the post-glacial Baltic Sea. We first show that populations are adapted to local salinity in a key reproductive trait, the proportion of motile sperm. Thereafter, we show that genome variation at 22,190 single nucleotide polymorphisms (SNPs) shows strong differentiation among populations along the gradient. Sequences containing outlier SNPs and transcriptome sequences, mapped to a draft genome, reveal associations with genes with relevant functions for adaptation in this environment but without overall evidence of functional enrichment. The many contigs involved suggest polygenic differentiation. We trace the origin of this differentiation using demographic modelling and find the most likely scenario is that at least part of the genetic differentiation is older than the Baltic Sea and is a result of isolation of two lineages prior to the current contact over the North Sea-Baltic Sea transition zone.
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| 25. |
- Lindahl, Jesper, et al.
(författare)
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Add-on pramipexole for anhedonic depression : study protocol for a randomised controlled trial and open-label follow-up in Lund, Sweden
- 2023
-
Ingår i: BMJ Open. - : BMJ Publishing Group. - 2044-6055. ; 13:11, s. 9
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Many depressed patients do not achieve remission with available treatments. Anhedonia is a common residual symptom associated with treatment resistance as well as low function and quality of life. There are currently no specific and effective treatments for anhedonia. Some trials have shown that dopamine agonist pramipexole is efficacious for treating depression, but more data is needed before it could become ready for clinical prime time. Given its mechanism of action, pramipexole might be a useful treatment for a depression subtype characterised by significant anhedonia and lack of motivation-symptoms associated with dopaminergic hypofunction. We recently showed, in an open-label pilot study, that add-on pramipexole is a feasible treatment for depression with significant anhedonia, and that pramipexole increases reward-related activity in the ventral striatum. We will now confirm or refute these preliminary results in a randomised controlled trial (RCT) and an open-label follow-up study. METHODS AND ANALYSIS: Eighty patients with major depression (bipolar or unipolar) or dysthymia and significant anhedonia according to the Snaith Hamilton Pleasure Scale (SHAPS) are randomised to either add-on pramipexole or placebo for 9 weeks. Change in anhedonia symptoms per the SHAPS is the primary outcome, and secondary outcomes include change in core depressive symptoms, apathy, sleep problems, life quality, anxiety and side effects. Accelerometers are used to assess treatment-associated changes in physical activity and sleep patterns. Blood and brain biomarkers are investigated as treatment predictors and to establish target engagement. After the RCT phase, patients continue with open-label treatment in a 6-month follow-up study aiming to assess long-term efficacy and tolerability of pramipexole. ETHICS AND DISSEMINATION: The study has been approved by the Swedish Ethical Review Authority and the Swedish Medical Products Agency. The study is externally monitored according to Good Clinical Practice guidelines. Results will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT05355337 and NCT05825235.
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| 26. |
- Lundgårdh, Filip, et al.
(författare)
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Epidemiology of hip- and groin injuries in Swedish male first football league
- 2020
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Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer. - 0942-2056 .- 1433-7347. ; 28:4, s. 1325-1332
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Tidskriftsartikel (refereegranskat)abstract
- Purpose This study aimed to investigate the incidence, pattern and burden of hip/groin injuries in Swedish professional male football players over five consecutive seasons.Methods Injury history from 16 football teams in the Swedish male first football league was evaluated during five consecutive seasons. The team’s medical staff recorded team exposure and time-loss injuries prospectively between 2012 and 2016.Results In total, 467 time-loss injuries located in the hip/groin area were recorded among 1,687 professional male football players, with an overall incidence and burden of 0.82/1,000 h and 15.6/1,000 h, respectively. There appeared to be an increased risk of hip/groin injuries during the last two seasons (2015-2016); however, the difference was not statistically significant (n.s). Recurrent injury rate was relatively low (14%), and overuse injuries accounted for the majority of injuries and absence days. Muscle injuries were the main injury type, while kicking and sprinting/running were the primary causes of injury. Goalkeepers had the lowest percentage of injuries and absence days.Conclusion Hip/groin injuries are a substantial problem in football, but does not seem to be an increasing phenomenon in the Swedish male first football league. Index and overuse injuries accounted for the majority of injuries and absence days. Thus, the focus should be on preventing hip/groin injuries to lower the injury rate. These new findings should be taken into consideration when designing and implementing preventive training interventions.
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| 27. |
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| 28. |
- Neuvonen, Pekka T., et al.
(författare)
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Defect evolution and impurity migration in Na-implanted ZnO
- 2011
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 84:20, s. 205202-
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Tidskriftsartikel (refereegranskat)abstract
- Secondary ion mass spectrometry (SIMS) and positron annihilation spectroscopy (PAS) have been applied to study impurity migration and open volume defect evolution in Na(+) implanted hydrothermally grown ZnO samples. In contrast to most other elements, the presence of Na tends to decrease the concentration of open volume defects upon annealing and for temperatures above 600 degrees C, Na exhibits trap-limited diffusion correlating with the concentration of Li. A dominating trap for the migrating Na atoms is most likely Li residing on Zn site, but a systematic analysis of the data suggests that zinc vacancies also play an important role in the trapping process.
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| 29. |
- Neuvonen, Pekka T., et al.
(författare)
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Interaction between Na and Li in ZnO
- 2009
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 95:24
-
Tidskriftsartikel (refereegranskat)abstract
- The interaction between group-Ia elements in ZnO have been studied by implanting Na into hydrothermally grown ZnO samples containing similar to 4x10(17) Li/cm(3) and employing secondary ion mass spectrometry for sample analysis. Postimplantation annealing above 500 degrees C results in a diffusion of Na and concurrently Li is efficiently depleted from the regions occupied by Na. The data show unambiguously that Na and Li compete for the same trapping site and the results provide strong experimental evidence for that the formation energies of Na on Zn site together with that of interstitial Li are lower than those of Li on Zn site and interstitial Na in highly resistive ZnO. This conclusion is also supported by recent theoretical estimates of the formation energies of these species as a function of the Fermi-level position in ZnO.
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| 30. |
- Nygård, Per, et al.
(författare)
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Damage Mechanisms in Paper
- 2006
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Ingår i: 2006 Progress in Paper Physics.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 31. |
- Nylander, Filip, 1986, et al.
(författare)
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New features of arabinoxylan ethers revealed by using multivariate analysis
- 2019
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617. ; 204, s. 255-261
-
Tidskriftsartikel (refereegranskat)abstract
- © 2018 Hemicelluloses are a relatively unused renewable resource. One reason is their broad structure variety that makes it hard to understand structure-property relations. In this study arbinoxylan, extracted from barley husk, was chemically modified into hydroxypropyl methyl-, hydroxypropyl- and methyl arabinoxylan. The relationship between structure and phase behavior was investigated by using multivariate analysis. The arabinoxylan ethers were characterized using mid-infrared FTIR spectroscopy and from principal components analysis, PCA, structural or physical variations between samples were visualized. With orthogonal projections to latent structures, OPLS, vibrations specific for arabinoxylan hydroxypropyl and methyl substitutions was assigned. Among the observed differences between chemical derivatives was an intensity change in the water vibration. The differences in hydration were related to clouding phase behavior of the arabinoxylan ethers. This study shows that multivariate analysis methods are useful for finding unexpected and/or hidden features in the polysaccharide structure.
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| 32. |
- Punzi, Marisa, et al.
(författare)
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Combined anaerobic-ozonation process for treatment of textile wastewater : Removal of acute toxicity and mutagenicity
- 2015
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 292, s. 52-60
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Tidskriftsartikel (refereegranskat)abstract
- A novel set up composed of an anaerobic biofilm reactor followed by ozonation was used for treatment of artificial and real textile effluents containing azo dyes. The biological treatment efficiently removed chemical oxygen demand and color. Ozonation further reduced the organic content of the effluents and was very important for the degradation of aromatic compounds, as shown by the reduction of UV absorbance. The acute toxicity toward Vibrio fischeri and the shrimp Artemia salina increased after the biological treatment. No toxicity was detected after ozonation with the exception of the synthetic effluent containing the highest concentration, 1. g/l, of the azo dye Remazol Red. Both untreated and biologically treated textile effluents were found to have mutagenic effects. The mutagenicity increased even further after 1. min of ozonation. No mutagenicity was however detected in the effluents subjected to longer exposure to ozone. The results of this study suggest that the use of ozonation as short post-treatment after a biological process can be beneficial for the degradation of recalcitrant compounds and the removal of toxicity of textile wastewater. However, monitoring of toxicity and especially mutagenicity is crucial and should always be used to assess the success of a treatment strategy. © 2015 Elsevier B.V.
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| 33. |
- Ruzicka, Filip, et al.
(författare)
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The search for sexually antagonistic genes : Practical insights from studies of local adaptation and statistical genomics
- 2020
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Ingår i: Evolution letters. - : Oxford University Press (OUP). - 2056-3744. ; 4:5, s. 398-415
-
Tidskriftsartikel (refereegranskat)abstract
- Sexually antagonistic (SA) genetic variation—in which alleles favored in one sex are disfavored in the other—is predicted to be common and has been documented in several animal and plant populations, yet we currently know little about its pervasiveness among species or its population genetic basis. Recent applications of genomics in studies of SA genetic variation have highlighted considerable methodological challenges to the identification and characterization of SA genes, raising questions about the feasibility of genomic approaches for inferring SA selection. The related fields of local adaptation and statistical genomics have previously dealt with similar challenges, and lessons from these disciplines can therefore help overcome current difficulties in applying genomics to study SA genetic variation. Here, we integrate theoretical and analytical concepts from local adaptation and statistical genomics research—including FST and FIS statistics, genome‐wide association studies, pedigree analyses, reciprocal transplant studies, and evolve‐and‐resequence experiments—to evaluate methods for identifying SA genes and genome‐wide signals of SA genetic variation. We begin by developing theoretical models for between‐sex FST and FIS, including explicit null distributions for each statistic, and using them to critically evaluate putative multilocus signals of sex‐specific selection in previously published datasets. We then highlight new statistics that address some of the limitations of FST and FIS, along with applications of more direct approaches for characterizing SA genetic variation, which incorporate explicit fitness measurements. We finish by presenting practical guidelines for the validation and evolutionary analysis of candidate SA genes and discussing promising empirical systems for future work.
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| 34. |
- Sköldberg, Filip, et al.
(författare)
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A population-based case-control study on statin exposure and risk of acute diverticular disease
- 2016
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 51:2, s. 203-210
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Tidskriftsartikel (refereegranskat)abstract
- Objective: A reduced risk of perforated diverticular disease among individuals with current statin exposure has been reported. The aim of the present study was to investigate whether statins reduce the risk of acute diverticular disease. Material and methods: A nation-wide population-based case-control study was performed, including 13,127 cases hospitalised during 2006-2010 with a first-time diagnosis of colonic diverticular disease, and 128,442 control subjects (matched for sex, age, county of residence and calendar year). Emergency surgery, assumed to be a proxy for complicated diverticulitis, was performed on 906 of the cases during the index admission, with 8818 matched controls. Statin exposure was classified as "current" or "former" if a statin prescription was last dispensed <= 125 days or >125 days before index date, respectively. The association between statin exposure and acute diverticular disease was investigated by conditional logistic regression, including models adjusting for country of birth, educational level, marital status, comorbidities, nonsteroidal anti-inflammatory drug/steroid exposure and healthcare utilisation. Results: A total of 1959 cases (14.9%) and 16,456 controls (12.8%) were current statin users (crude OR 1.23 [95% CI 1.17-1.30]; fully adjusted OR 1.00 [0.94-1.06]). One hundred and thirty-two of the cases subjected to surgery (14.6%), and 1441 of the corresponding controls (16.3%) were current statin users (crude OR 0.89 [95% CI 0.73-1.08]; fully adjusted OR 0.70 [0.55-0.89]). Conclusions: The results do not indicate that statins affect the development of symptomatic diverticular disease in general. However, current statin use was associated with a reduced risk of emergency surgery for diverticular disease.
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| 35. |
- Strand, Robin, et al.
(författare)
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Minimal Cost-Path for Path-Based Distances
- 2007
-
Ingår i: Proceedings of 5th International Symposium on Image and Signal Processing and Analysis (ISPA 2007). - 9789531841160 ; , s. 379-384
-
Konferensbidrag (refereegranskat)abstract
- Distance functions defined by the minimal cost-path using weights and neighbourhood sequences (n.s.) are considered for the constrained distance transform (CDT). The CDT is then used to find one minimal cost-path between two points. The behaviour of some path-based distance functions is analyzed and a new error function is introduced. It is concluded that the weighted n.s.-distance with two weights (3 x 3 neighbourhood) and the weighted distance with three weights (5 x 5 neighbourhood) have similar properties in terms of minimal cost-path computation, while the former is more efficient to compute.
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| 36. |
- Svensson, Anders, 1960, et al.
(författare)
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Bottom bed regimes in a circulating fluidized bed boiler
- 1996
-
Ingår i: International Journal of Multiphase Flow. - 0301-9322. ; 22:6, s. 1187-1204
-
Tidskriftsartikel (refereegranskat)abstract
- This paper extends previous work on the fluidization regimes of the bottom bed of circulating flyidized bed (CFB) boilers. Pressure measurements were performed to obtain the time-average bottom bed voidage and to study the bed pressure fluctuations. The measurements were carried out in a 12 MWth CFB boiler operated at 850°C and also under ambient conditions (40°C). Two bubbling regimes were identified: a “single bubble regime” with large single bubbles present at low fluidization velocities, and, at high fluidization velocities, an “exploding bubble regime” with bubbles often stretching all the way from the air distributor to the surface of the bottom bed. The exploding bubble regime results in a high through-flow of gas, indirectly seen from the low average voidage of the bottom bed, which is similar to that of a stationary fluidized bed boiler, despite the higher gas velocities in the CFB boiler. Methods to determine the fluidization velocity at the transition from the single to the exploding bubble regime are proposed and discussed. The transition velocity increases with an increase in particle size and bed height.
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| 37. |
- Svensson, Anton Filip, et al.
(författare)
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Remission rate of transcranial magnetic stimulation compared with electroconvulsive therapy : a case-control study
- 2019
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Ingår i: Nordic Journal of Psychiatry. - : Taylor & Francis. - 0803-9488 .- 1502-4725. ; 72:7, s. 471-476
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To compare the rate of remission, rate of response, change in depressive symptoms, and adverse effects between repetitive transcranial magnetic stimulation (rTMS) and electroconvulsive therapy (ECT).MATERIALS AND METHODS: In this retrospective case-control study, 35 patients treated for depression with rTMS (left dorsolateral prefrontal cortex, 90% observed motor threshold, 10 Hz, 2000 pulses/session, 15 sessions) at Örebro University Hospital, Sweden (cases), were compared with a matched group of 35 patients treated for depression with ECT (controls). Data on controls were obtained from the Swedish National Quality Register for ECT (Q-ECT). Severity of depression was evaluated using the Montgomery-Åsberg Depression rating scale (MADRS).RESULTS: Remission rate was 26% for cases and 43% for controls (p = .3). Response rate was 40% for cases and 51% for controls (p = .63). The median decrease in MADRS was 11 (IQR 3-19) vs. 17 (IQR 6-27; p = .10) for rTMS and ECT, respectively. There was no statistically significant difference in any measure of treatment effect between rTMS and ECT. More than half of the patients of the rTMS group experienced scalp discomfort and 11% of the ECT group had memory disturbances.CONCLUSIONS: All measures of therapeutic efficacy were numerically inferior in the rTMS group compared to the ECT group. The differences were not statistically significant, probably because the sample size was small. More studies are required to find the optimal place for rTMS within the Swedish health care system. Such studies could be facilitated by inclusion of rTMS in the Q-ECT.
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| 38. |
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| 39. |
- Svensson, Anders, 1960, et al.
(författare)
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Fluidization regimes in non-slugging fluidized beds: the influence of pressure drop across the air distributor
- 1996
-
Ingår i: Powder Technology. - 1873-328X .- 0032-5910. ; 86:3, s. 299-312
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present work is to study the influence of the pressure drop across the air distributor on the bubbling conditions of thebottom bed of circulating fluidized beds (CFB). The bottom bed is the dense bubbling zone just above the distributor. The experimental workwas carried out in a 12 MWm CFB boiler and in a cold CFR Three different distributions of the bubble flow in time and space, termedfluidization regimes, were identified in the cold CFB: the multiple bubble regime with many small bubbles evenly distributed in the bed; thesingle bubble regime, characterized by the presence of only one bubble at a time in the bed; and the exploding bubble regime with large,single, irregular voids stretching from the air distributor to the bed surface. These bubbling conditions were observed during variations in thegas velocity and the distributor pressure drop. A comparison with the 2 mz cross-section CFB boiler showed that the boiler always operatesin the single or in the exploding bubble regime, which indicates a bubble flow that is not continuous and not well distributed over the crosssectionof the bed. The conditions in the boiler are influenced by the relatively large area of gas passage and the low pressure drop of theboiler air distributor.
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| 40. |
- Svensson, Bengt Gunnar, et al.
(författare)
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Hydrothermally Grown Single-Crystalline Zinc Oxide; Characterization and Modification
- 2007
-
Ingår i: MRS Proceedings Volume 1035 / 2007. - Warrendale, PA, USA : Materials Research Society.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- An overview of our recent results on characterization and modification of high-resistivity n-type bulk zinc oxide samples, grown by hydrothermal techniques, is given. Three specific topics are addressed; (i) the role of lithium (Li) as an electrically compensating impurity, (ii) extrinsic n-type doping by hydrogen implantation, and (iii) influence of annealing conditions on deep band emission. In (i), furnace annealing of as-grown samples at temperatures above ∼800 °C is shown to cause out-diffusion of residual Li impurities and concurrently, the resistivity decreases. After annealing at 1400 °C, a resistivity close to 10−1 Ωcm is obtained and the Li content is reduced from above 1017 cm−3 to the mid 1015 cm−3 range, providing evidence for the crucial role of Li as an electrically compensating impurity. For ion-implanted samples, vacancy clusters evolve during post-implant flash lamp annealing (20 ms duration) and these clusters appear to trap and deactivate Li with a resulting improvement of the n-type conductivity. However, these clusters have a limited stability and start to dissociate already after 1h at 900 °C, accompanied by a decrease in the conductivity. For topic (ii), n-type doping by hydrogen implantation is shown to enhance the conductivity by about 5 orders of magnitude already in the as-implanted state. Despite substantial loss of hydrogen, the conductivity remains stable, or even increases, after annealing up to ≥600 °C, and necessary conditions for doping by hydrogen are discussed. In (iii), the origin of the commonly observed deep band emission from monocrystalline zinc oxide is investigated using a concept of annealing as-grown samples in different atmospheres. A strong influence by the atmosphere and temperature is observed and the results can be interpreted in terms of dominant effects on the emission by vacancy-related defects.
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| 41. |
- Svensson, Filip, 1980-, et al.
(författare)
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Diatom Cell Size, Coloniality and Motility : Trade-Offs between Temperature, Salinity and Nutrient Supply with Climate Change
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:10
-
Tidskriftsartikel (refereegranskat)abstract
- Reduction in body size has been proposed as a universal response of organisms, both to warming and to decreased salinity. However, it is still controversial if size reduction is caused by temperature or salinity on their own, or if other factors interfere as well. We used natural benthic diatom communities to explore how body size'' (cells and colonies) and motility change along temperature (2-26 degrees C) and salinity (0.5-7.8) gradients in the brackish Baltic Sea. Fourth-corner analysis confirmed that small cell and colony sizes were associated with high temperature in summer. Average community cell volume decreased linearly with 2.2% per degrees C. However, cells were larger with artificial warming when nutrient concentrations were high in the cold season. Average community cell volume increased by 5.2% per degrees C of artificial warming from 0 to 8.5 degrees C and simultaneously there was a selection for motility, which probably helped to optimize growth rates by trade-offs between nutrient supply and irradiation. Along the Baltic Sea salinity gradient cell size decreased with decreasing salinity, apparently mediated by nutrient stoichiometry. Altogether, our results suggest that climate change in this century may polarize seasonality by creating two new niches, with elevated temperature at high nutrient concentrations in the cold season (increasing cell size) and elevated temperature at low nutrient concentrations in the warm season (decreasing cell size). Higher temperature in summer and lower salinity by increased land-runoff are expected to decrease the average cell size of primary producers, which is likely to affect the transfer of energy to higher trophic levels.
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| 42. |
- Svensson, Filip, 1980-
(författare)
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Effects of warming on the ecology of algal-dominated phytobenthic communities in the Baltic Sea
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Through climate change, the global average air and surface water temperature has risen 0.85°C during the last 100 years. The Baltic Sea experienced one of the most rapid increase in temperature recorded of marine ecosystems. During the last two decades of the 20th century, the surface water temperature of the Baltic Sea has increased seven times faster than the global average.This thesis is an investigation of how community traits, trophic interactions and ecophysiological processes in the filamentous algal belt in the northern Baltic Sea are affected by warming. The majority of the studies were conducted in or in the vicinity of the Forsmark Biotest basin, an artificial heated enclosure of the southern Bothnian Sea (northern Baltic Sea). One study also included sampling along a natural salinity gradient - the Swedish east coast.In the benthic diatom community, we found that cell size decreases with decreasing seasonal temperature, and increased with warming during the cold season. Warming also selected for motile and colonial traits. Along the salinity gradient, cell size decreased with decreasing salinity, apparently mediated by changes in the nitrogen to phosphorus ratio.In the filamentous algal community, warming increased algal cover and photosynthetic capacity, and affected the ratio of carotene to chlorophyll a ratio. Warming also desensitized the photosynthetic response and growth of algal communities exposed to anthropogenic stressors: increased nitrogen and phosphor concentrations as well as copper additions. In connection to one of the field studies, the first finding of the non-native bivalve Mytilopsis leucophaeata in Sweden was also done.Using a fish exclusion experiment in heated and non-heated areas, we found that warming decreases the number of trophic levels in the lower parts of the food web, which in turn lead to increased top-down control and higher algal biomass at heated than unheated sites.In summary, warming has here been shown to have major impacts on the phytobenthic community due to a combination of direct effects on physiological processes, as well as indirect effects mediated by interactions among species and trophic levels.
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| 43. |
- Svensson, Filip, et al.
(författare)
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Expeditionsrapport för 2017 års fiskäggundersökning i Bohusläns skärgårds- och fjordområden
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I äggundersökningen i Bohusläns skärgårds- och fjordområde som genomfördes under tre veckor (v. 9, 14 och 17) våren 2017 kunde ägg från total 16 olika fiskarter identifieras med hjälp av så kallade genetiska streckkodsmarkörer. Provtagningsområdet sträckte sig inomskärs från Smögen i norr till Marstrand i söder. Tidiga stadier av fiskägg (stadie Ia-Ib), som indikation på eventuell lokal lek identifierades för arterna: torsk, lerskädda, sandskädda, rödspätta, skarpsill och skrubbskädda. Ägg från ytterligare två torskfiskar - vitling och bleka kunde identifieras dock utan att specifika äggstadier kunde bestämmas. Största koncentrationen av torskägg (alla stadier) hittades utanför Brofjorden samt i Gullmarsfjorden och runt ön Lyr mellan Orust och Tjörn. Tidiga stadier av torskägg (stadie Ia-Ib) hittades framförallt utanför Brofjorden och runt ön Lyr. Plattfiskägg hittades över hela provtagningsområdet dock med en viss koncentration av ägg från rödspätta i och utanför Brofjorden.
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| 44. |
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| 45. |
- Svensson, Filip, et al.
(författare)
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In situ warming strengthens trophic cascades in a coastal food web
- 2017
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Ingår i: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 126:8, s. 1150-1161
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Tidskriftsartikel (refereegranskat)abstract
- Global warming may affect most organisms and their interactions. Theory and simple mesocosm experiments suggest that consumer top-down control over primary producer biomass should strengthen with warming, since consumer respiration increases faster with warming than plant photosynthesis. However, these predictions have so far not been tested on natural communities that have experienced warming over many generations. Natural systems display a higher diversity, heterogeneity and complexity than mesocosms, which could alter predicted effects of warming. Here we used an artificially heated part of the northern Baltic Sea (the Forsmark Biotest basin) to test how warming influences trophic interactions in a shallow coastal food web with four trophic levels: omnivorous fish, invertivorous fish, herbivorous invertebrates, and filamentous macroalgae. Monitoring of fish assemblages over six years showed that small invertivorous fish (gobiids, sticklebacks and minnows) were much less abundant in the heated basin than in unheated references areas. Stomach content analyses of the dominating omnivorous fish - Eurasian perch Perca fluviatilis - revealed a strikingly different diet within and outside the Biotest basin; gammarid crustaceans were the dominating prey at heated sites, whereas invertivorous fish (e.g. gobiids) dominated at unheated sites. A 45-day cage experiment showed that fish exclusion did not affect the biomass of algal herbivores (gastropods and gammarids), but reduced algal biomass in heated sites (but not unheated). This suggests that warming induced a trophic cascade from fish to algae, and that this effect was mediated by predator-induced changes in herbivore behavior, rather than number. Overall, our study suggests that warming has effectively compressed the food chain from four to three trophic levels (algae, gammarids and perch), which have benefitted the primary producers by reducing grazing pressure. Consequently, warming appears to have restructured this coastal food web through a combination of direct (physiological) and indirect (species interactions) effects.
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| 46. |
- Svensson, Filip, et al.
(författare)
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Kusttrålundersökning 2022 – Övervakning av bottenlevande fisk längs svenska västkusten
- 2023
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Detta är expeditionsrapporten för 2022 års kusttrålundersökning längs svenska västkusten som övervakar det kustnära och bottenlevande fisksamhället. Undersökningen har utförts årligen sedan 2001 med syfte att inventera artsammansättningen och rekryteringen av bottenlevande fisk i allmänhet, samt förekomst av stor torsk (Gadus morhua) i synnerhet. Undersökningen tillför även grundläggande data avseende indikatorer för kustfiskarter inom ramen för arbetet med Havsmiljödirektivet. Undersökningsområdet sträcker sig från utsjöbanken Fladen i norra Kattegatt till Singlefjorden vid norska gränsen i Skagerrak.Under 2022 utfördes undersökning mellan 5 och 16 september. Totalt trålades 31 stationer, varav sju låg i utsjön och 24 låg vid kusten och i fjordarna.Torskfångsterna var fortsatt låga och 0-grupp (<18 cm) dominerade. Endast tre torskar över 40 cm fångades. Noterbart var de stora fångsterna av 0-grupp (<17 cm) kolja (Melanogrammus aeglefinus) som förekom på alla lokaler. Även 1-grupp kolja (<30 cm) fångades på några lokaler vid norska gränsen och i Gullmarsfjorden. Fångsterna av kolja under 2022 var de största som noterats sedan provtagningen startade 2001. Två arter av rocka fångades - klorocka (Amblyraja radiata) och knaggrocka (Raja clavata). Två juvenila exemplar av den rödlistade (kategori: ENstarkt hotad) och sällsynta hälleflundran (Hippoglossus hippoglossus) kunde också noteras. Totalt fångades 36 fiskarter, tre arter av bläckfiskar samt havskräfta (Nephrops norvegicus) och hummer (Homarus gammarus).
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| 47. |
- Svensson, Filip, et al.
(författare)
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Rapport för 2018 års kusttrålningsundersökning av kustnära fiskbestånd längs den svenska västkusten
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Kusttrålningar har genomförts längs svenska kusten i Västerhavet sedan 2001. En huvudsaklig målsättning sedan starten har varit att övervaka utvecklingen av lokala bestånd och kustkomponenter av bestånd för ett urval av fiskarter med särskild fokus på torsk. Sedan 2009 är provtagningen fokuserad till kustavsnittet med skärgård mellan Fladen banken i söder och Singlefjorden i norr och sedan 2013 är provtagningen anpassad för att även övervaka fisksamhällets utveckling för Havsmiljödirektivet vad det gäller biologisk mångfald och marina näringsvävar. Årets kusttrålning genomfördes den 3-13 september 2018 då sammanlagt 32 trålstationer besöktes i norra Västerhavet. I kustområden gjordes 24 tråldrag och i utsjön gjordes åtta tråldrag. Fångsterna av torsk längs kusten under 2018 låg i stort sätt på samma låga nivå som föregående år. Förekomsten av stor könsmogen torsk längs kusten var fortsatt mycket låg; den största torsken som fångades i kustområdena under 2018 var 56 cm lång och fångades i Askeröfjorden. Fångsterna av torsk i utsjön under 2018 indikerar i jämförelse med 2017 års provtagning en fortsatt minskning. Fångsterna av torsk i utsjön 2018 var de lägsta som registrerats sedan provtagningen började. Vitling är en av de vanligaste fiskarterna som fångas i kusttrålningen under de senaste åren (2013-2018). De negativa trenderna för vitling både i utsjön och i kustområdena fortsatte under 2018 på samma sätt som under 2017. Fångstnivåerna för kolja i kustområdena var på en liknande nivå som under 2017 års kusttrålning samtidigt som koljan i utsjön befann sig på den lägsta nivå som registrerats sedan kusttrålningen startade. Generellt, vad det gäller torskfiskar så utgjordes fångsterna nästan uteslutande av juvenil fisk. Två arter av rocka fångades – knaggrocka och klorocka. Totalt fångades 48 olika fiskarter.
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| 48. |
- Svensson, Filip, et al.
(författare)
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Undersökning av ägg från vinterlekande fiskarter 2017-2022 i Bohusläns skärgårds- och fjordområden
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport sammanfattar resultaten från äggundersökning av pelagiala fiskägg i skärgårds- och fjordområdena mellan Smögen och Stenungsund under första och andra kvartalet för åren 2017- 2022. Totalt kunde ägg från 25 olika fiskarter identifieras med hjälp av DNA-sekvensering. För dessa fiskarter kunde tidiga äggstadier, som indikation för lokal lek, identifieras för 19 olika arter däribland kommersiellt viktiga fiskarter så som torsk (Gadus morhua), rödspätta (Pleuronectes platessa), äkta tunga (Solea solea) makrill (Scomber scombrus) och skarpsill (Sprattus sprattus).I analysen delades fiskäggen upp i två storleksfraktioner: ägg med diameter större eller lika med 1,2 mm och ägg mindre än 1,2 mm. Ägg i den större storleksfraktionen analyserades med avseende på art, storlek och utvecklingsstadie för varje lokal (ett håvdrag), ägg i den mindre storleksfraktionen slogs samman per område (ex. alla lokaler i en fjord) och där analyserades endast artsammansättning av DNA-sekvenser i det sammanslagna provet. I den större storleksfraktionen förekom flest ägg av torsk, skarpsill, rödspätta och lerskädda (Hippoglossoides platessoides), och i den mindre storleksfraktionen dominerade dna-sekvenser från sandskädda (Limanda limanda), skrubbskädda (Platichthys flesus), vitlinglyra (Trisopterus esmarkii), glyskolja (Trisopterus minutus) och femtömmad skärlånga (Ciliata mustela).
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