| 1. |
- Andersson, Magnus, et al.
(author)
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Fiskbestånd och miljö i hav och sötvatten : Resurs- och miljööversikt 2012
- 2012
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Reports (other academic/artistic)abstract
- Detta är den nionde utgåvan av den samlade översikten över fisk- och kräftdjursbeståndens status i våra vatten. Kunskap om fiskbestånden och miljön är en förutsättning för att utnyttjandet av fiskresurserna skall bli bärkraftigt. För svenska vattenområden beskrivs miljöutvecklingen i ett ekosystemsperspektiv, dels för att tydliggöra fiskens ekologiska roll och beskriva yttre miljöfaktorer som påverkar fiskbestånden, dels för att belysa fiskets effekter på miljön.Fiskbestånd och miljö i hav och sötvatten är utarbetad av Sveriges lantbruksuniversitet (SLU), Institutionen för akvatiska resurser (SLU Aqua), på uppdrag av Havs- och vattenmyndigheten. Rapporten sammanfattar utveckling och beståndsstatus för de kommersiellt viktigaste fisk- och kräftdjursarterna i våra vatten. Bedömningar och förvaltningsråd är baserade på Internationella Havsforskningsrådets (ICES) rådgivning, SLU Aquas nationella och regionala provfiskedata, samt yrkesfiskets rapportering.
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| 2. |
- Hedström, Brita, et al.
(author)
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Visby Innerstad : En användningsplan
- 1973
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Reports (pop. science, debate, etc.)abstract
- Sedan lång tid föreligger i stort sett enighet om att bevara innerstadens bebyggelse och att anpassa eventuella nytillskott till det redan bestående. Med den inställningen har förändringsprocessen både dämpats och mildrats men ändå inte bragts att avstanna. Förändringar sker ständigt om det också huvudsakligen i smått: de många synbart så anspråkslösa byggnadsåtgärderna adderar efterhand ihop sig till något större och mer genomgripande. Långsamt, nästan omärkligt, ändrar innerstaden sitt ansikte.Ändå är det inte själva husen som förändrats mest utan användningen av dem. Ur funktionell synpunkt har 1950 - och 60-talen har varit något av en omstörtning i innerstadens historia: den har förlorat nästan hälften av de boende, en stor del av detaljhandeln och praktiskt taget helt sin gamla roll som skolcentrum. I gengäld har ytterstaden vuxit ut till ett sammanhängande kilometerbrett bälte. Till stor del av denna funktionella förändring en följd av beslutet att bevara innerstadens bebyggelse. Vad som inte fått plats inom den gamla ramen har etablerats utandör den.Föreliggande arbete vill ge en översiktlig bild av förändringsförloppen, sedda i ett långt tidsperspektiv men med tonvikt på dagsläget. Bebyggelsen tas upp till utförlig granskning men också användningen av den. Det är just samspelet mellan husen och de funtkioner, de fyller, som kan sägas utgöra bokens huvudtema. I de flesta fall är detta sammanhang hus-användning alldeles konfliktfritt och föranleder därför inte heller någon diskussion. Vad som behandlas är de relativt få problematiska fallen, hus som borde rustas upp för att fylla sin uppgift, hus som är olämpligt nyttjade eller inte använda alls. En serie sådana fall tas upp till systematisk genomgång; samtidigt berörs också de trafik - och miljömässiga konsekvenserna. Bokens syfte är alltså klart: den ger ett underlag av fakta för arbetet med att jämka samman byggnader och användningsformer. I den meningen kan skriften kallas en anvädningsplan för Visby innanför murarna.Arkitekturskolanas arbete har bedrivitis parallellt med den kommunala Innerstadskommitténs verksamhet. Något organiserat samarbete har inte förekommit med de informella kontakterna har varit både täta och goda. Att likheterna mellan Innerstadskommittén och Arkitekturskolans slutsatser blivit så pass stora, kan tillskrivas en gemensam helhetssyn.En av Arkitekturskolans elever, arkitekt Lars-Ingvar Larsson, har tidigare självständigt genomfört en undersökning av förändringar i innerstaden 1945-70- Denna studie publicerats separat och bör uppfattas som ett komplement till den hör föreliggande.Förutom de i innehållsförteckningen nämnda har ytterligare några aktivt medverkat i arbetet. Studiet av trafikfrågorna i innerstaden, i hamnen och öster om ringmuren leddes av Åke Claesson, I fältstudier och diskussioner medverkande Göran Månsson.Arkitekturskolan har fått god hjälp av ett antal initierade personer i Visby. Särskild tacksamhet är vi skyldiga byggnadsnämnden ordförande Henning Jacobson, kommunalrådet C B Stenström, stadsarkitekten Måns Hagbergm f. länsbostadsdorektören Åke Malmberg och landsantikvarien Gunnar Svahnström. I boken publiceringskostnaderna har ekonomiskt bidrag lämnats av Gotlands kommun och Riksantikvarieämbetet.Boken har redigerats av Sture Balgård och Ann Mari Westerlind med hjälp av Henrik O Andersson, Bo Ek, Göran Lindahl, Fredrik von Platen, John Sjöström Gunnar Westerlind och Hans Wetterfors.Skeppsholmen, Stockholm, sommaren 1973.Arkitekturskolans lärare och elever.
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| 3. |
- Merino, Irene, et al.
(author)
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Metabolomic and transcriptomic analyses identify external conditions and key genes underlying high levels of toxic glycoalkaloids in tubers of stress-sensitive potato cultivars
- 2023
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In: Frontiers in Plant Science. - 1664-462X. ; 14
-
Journal article (peer-reviewed)abstract
- Introduction: High levels of toxic steroidal glycoalkaloids (SGAs) in potato tubers constitute a recognized food quality problem. Tuber SGA levels vary between potato cultivars and can increase after post-harvest stresses such as wounding and light exposure. A few cultivars, e.g., ‘Magnum Bonum’ and ‘Lenape,’ have been withdrawn from commercial sales due to excessive SGA levels during some cultivation years. However, these sudden SGA increases are diffucult to predict, and their causes are not understood. To identify external and genetic factors that underlie sudden SGA increases in certain potato cultivars, we have here in a 2-year study investigated ‘Magnum Bonum’ and five additional table potato cultivars for their SGA levels after wounding and light exposure. Results and methods: Results showed that ‘Magnum Bonum’ has an unusual strong SGA response to light exposure, but not to wounding, whereas ‘Bintje’ displayed an opposite regulation. Levels of calystegine alkaloids were not significantly altered by treatments, implicating independent metabolic regulation of SGA and calystegine levels also under conditions of high SGA accumulation. Metabolomic and transcriptomic analyses identified a small number of key genes whose expression correlated with SGA differences between cultivars. Overexpression of two key genes in transgenic low-SGA potato cultivars increased their leaf SGA levels significantly. Discussion: The results show that a strong response to light can underlie the SGA peaks that occasionally occur in certain potato cultivars and indicate that a between-cultivar variation in the expression of single SGA key genes can account for cultivar SGA differerences. We propose that current attempts to mitigate the SGA hazard will benefit from an increased consideration of cultivar-dependent SGA responses to post-harvest conditions, particularly light exposure. The identified key SGA genes can now be used as a molecular tool in this work.
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| 4. |
- Rosén, Johan, et al.
(author)
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A new method for analysis of underivatized free beta-methylamino-alanine : Validation and method comparison
- 2016
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In: Toxicon. - : Elsevier BV. - 0041-0101 .- 1879-3150. ; 121, s. 105-108
-
Journal article (peer-reviewed)abstract
- A new method was developed for analysis of free beta-Methylamino-alanine (BMAA) in biological matrices. The method is based on direct analysis of the underivatized molecule, using an amide column for separation by Hydrophilic Interaction Liquid Chromatography (HILIC) and detection by tandem mass spectrometry (MS/MS) using a deuterium labeled internal standard. The use of Ultra-High Performance Liquid Chromatography (UHPLC) combined with MS/MS detection allowed for high chromatographic resolution and a low limit of detection (0.025 mu g/g wet weight (ww) in mussels). The method was validated by analyzing spiked blank mussels from the Baltic Sea (0.15-4.4 mu g/g (ww), trueness 99%-105%, RSD 2%-8%). An inter-laboratory comparative analysis of extracts of mussel was performed. The mussels were extracted according to an established protocol for analysis of free BMAA, and the extracts were then analyzed in parallel by the new method and a validated procedure based on detection of BMAA derivatized with dansyl chloride. Both methods detected BMAA in similar concentrations. Thus, derivatization with dansyl chloride did not influence the results compared to direct detection. The new method presents an alternative to the commonly applied derivatization step, and is proved through validation and method comparison to reliably identify and quantify free BMAA at low concentration levels.
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| 5. |
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| 6. |
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A Place in Europe : Proposed project description peered by Project Anywhere
- 2017
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Artistic work (peer-reviewed)abstract
- This is not conceived as an exclusive work but rather a demonstrably inclusive one (albeit resistant to the logic of circular reproduction). Within the process of artistic research and a developing practice, new methods might constitute another form of art. The project has been centered upon the idea of a round table at which a number of people with different competences have collaborated productively to build the project. The divergent competences that make up the project team have all contributed to the development of A Place in Europe, and moreover worked to challenge conventional practices and forms of knowledge belonging to the various fields of expertise in order to foster a spirit of experimentation and novelty. The key point of departure for all collaborators has been the value of approaching the topic from a creative base, and in doing so striving to exchange ideas in a productive manner with others, both at the site and within the process of developing the project and presentation. We have also been collectively mindful of the potentially asymmetrical power relations at play in any process during which “we” film and interact with “them”. We do not seek to speak for ”them” but rather use our collective desire to explore a more inclusive society.
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| 7. |
- Acke, Filip, 1968, et al.
(author)
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Influence of the platinum-support interaction on the direct reduction of NOx under lean conditions
- 1998
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In: Studies in Surface Science and Catalysis. - 0167-2991. ; 116, s. 285-294
-
Journal article (peer-reviewed)abstract
- Catalysts containing Pt supported on SiC, Al2O3 and ZSM-5 were prepared and studied for NOx reduction by C3H6 in Oz excess under transient (temperature ramps) and steady-state conditions. The maximum NOx reduction activity in the heating ramp experiments was similar for Pt/SiC and Pt/ZSM-5, while Pt/Al2O3 showed higher maximum activity. Both N-2 and N2O formation was observed for all catalysts, although the respective amounts varied with the investigated system. Highest Nz selectivity was observed for Pt/Al2O3. When the NOx reduction activity was studied under steady-state conditions the activity of Pt/Al2O3 decreased substantially (mainly due to a loss in N-2 production). Pt/ZSM-5 became somewhat more selective towards Na production whereas the activity and selectivity of Pt/SiC remained at about the same values as far the heating ramp experiments. Adsorbed species on the surface of the different catalysts were investigated using in-situ FTIR in order to obtain information about the reaction mechanisms. The adsorption of species on Pt/SiC was negligible, while a number of absorption bands were observed for Pt/Al2O3 (N and C containing species, and -NCO) and Pt/ZSM-5 (HC).
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| 8. |
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| 9. |
- Amberntsson, Annika, 1974, et al.
(author)
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Sulphur dioxide deactivation of NOx storage catalysts
- 1999
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In: Studies in Surface Science and Catalysis. - 0167-2991. ; 126, s. 317-324
-
Journal article (peer-reviewed)abstract
- The influence of sulphur dioxide on the NOx storage performance of a Pt-Rh/BaO/Al2O3 model catalyst has been investigated. Addition of 2.5-25 vol.-ppm SO2 to a synthetic lean-burn exhaust, containing NO, C3H6, O2 and Ar, caused deactivation of the NOx storage function of the catalyst. The rate of deactivation was found to be proportional to the exposure of SO2. This effect is seen for temperatures between 250 and 450 degrees C. Together with in situ FTIR measurements, this leads to the conclusion that sulphur accumulates in the NOx storage component of the catalyst during the exposure. Furthermore, SO2 also inhibits the oxidation capacity of the catalyst during lean periods as is observed by a decreased NO oxidation activity. The presence of SO2 also reduces the reduction capacity of the catalyst under rich periods, which leads to an increased N2O formation and a decreased NO conversion.
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| 10. |
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| 11. |
- Baart, Pieter, et al.
(author)
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Contaminant particle migration in a double restriction seal
- 2013
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In: Proceedings of the STLE Annual Meeting and Exhibition 2013, Detroit MI, USA.. - : STLE. ; , s. 125-
-
Conference paper (peer-reviewed)abstract
- Microparticle image velocimetry (μPIV) is used to measure the grease velocity profile in small seal-like geometries and the radial migration of contaminant particles is predicted. In the first part, the influence of shaft speed, grease type, and temperatures on the flow of lubricating greases in a narrow double restriction sealing pocket is evaluated. Such geometries can be found in, for example, labyrinth-type seals. In a wide pocket the velocity profile is one-dimensional and the Herschel-Bulkley model is used. In a narrow pocket, it is shown by the experimental results that the side walls have a significant influence on the grease flow, implying that the grease velocity profile is two-dimensional. In this area, a single empirical grease parameter for the rheology is sufficient to describe the velocity profile.In the second part, the radial migration of contaminant particles through the grease is evaluated. Centrifugal forces acting on a solid spherical particle are calculated from the grease velocity profile. Consequently, particles migrate to a larger radius and finally settle when the grease viscosity becomes large due to the low shear rate. This behavior is important for the sealing function of the grease in the pocket and relubrication
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| 12. |
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| 13. |
- Baart, Pieter, et al.
(author)
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The influence of speed, grease type, and temperature on radial contaminant particle migration in a double restriction seal
- 2011
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In: Tribology Transactions. - : Informa UK Limited. - 1040-2004 .- 1547-397X. ; 54:6, s. 867-877
-
Journal article (peer-reviewed)abstract
- Microparticle image velocimetry (μPIV) is used to measure the grease velocity profile in small seal-like geometries and the radial migration of contaminant particles is predicted. In the first part, the influence of shaft speed, grease type, and temperatures on the flow of lubricating greases in a narrow double restriction sealing pocket is evaluated. Such geometries can be found in, for example, labyrinth-type seals. In a wide pocket the velocity profile is one-dimensional and the Herschel-Bulkley model is used. In a narrow pocket, it is shown by the experimental results that the side walls have a significant influence on the grease flow, implying that the grease velocity profile is two-dimensional. In this area, a single empirical grease parameter for the rheology is sufficient to describe the velocity profile. In the second part, the radial migration of contaminant particles through the grease is evaluated. Centrifugal forces acting on a solid spherical particle are calculated from the grease velocity profile. Consequently, particles migrate to a larger radius and finally settle when the grease viscosity becomes large due to the low shear rate. This behavior is important for the sealing function of the grease in the pocket and relubrication.
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| 14. |
- Bergman, Karl-Olof, et al.
(author)
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Butterflies in Swedish grasslands benefit from forest and respond to landscape composition at different spatial scales
- 2018
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In: Landscape Ecology. - : SPRINGER. - 0921-2973 .- 1572-9761. ; 33:12, s. 2189-2204
-
Journal article (peer-reviewed)abstract
- ContextLoss and fragmentation of semi-natural grasslands has critically affected many butterfly species in Europe. Habitat area and isolation can have strong effects on the local biodiversity but species may also be strongly affected by the surrounding matrix.ObjectivesWe explored how different land cover types in the landscape explained the occurrence of butterfly species in semi-natural grasslands.MethodsUsing data from 476 semi-natural grasslands in Sweden, we analysed the effect of matrix composition on species richness and occurrence. Additionally, we analysed at which spatial scales butterflies responded to matrix types (forests, semi-natural grasslands, arable land and water).ResultsForest cover showed the strongest positive effect on species richness, followed by semi-natural grasslands. Forest also had a positive effect on red-listed species at local scales. Responses to matrix composition were highly species-specific. The majority of the 30most common species showed strong positive responses to the amount of forest cover within 200-500m. There was a smaller group of species showing a positive response to arable land cover within 500-2000m. Thirteen species showed positive responses to the amount of semi-natural grasslands, generally at larger scales (10-30km).ConclusionsOur study showed that surrounding forest is beneficial for many grassland butterfly species and that forests might mitigate the negative effects of habitat loss caused by agricultural intensification. Also, semi-natural grasslands were an important factor for species richness at larger spatial scales, indicating that a landscape consisting mainly of supporting habitats (i.e. forests) are insufficient to sustain a rich butterfly fauna.
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| 15. |
- Byström, Erica
(author)
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Ett lärorikt arbete? : Möjligheter och hinder för undersköterskor att lära och utvecklas i sjukvårdsarbetet
- 2013
-
Doctoral thesis (other academic/artistic)abstract
- Avhandlingen, som är en kvalitativ studie, rör yrkesgruppen undersköterskor inom hälso- och sjukvården. Syftet med studien har varit att studera och bidra med ökad kunskap, dels om villkoren för lärande och kunskapsbildning i arbetslivet, dels mer specifikt om undersköterskors arbete, arbetsvillkor samt villkor för lärande och utveckling på arbetsplatsen.Avhandlingens teoretiska referensram utgår från tidigare forskning och teoribildning om arbetsrelaterat lärande som kunnat sammanfattas i en modell, i vilken fyra olika grupper av faktorer, som är betydelsefulla för lärande i och genom arbetet, beskrivs. De fyra är: 1) Arbetets och organisering 2) Formell och icke-formell utbildning 3) Sociala aspekter och 4) Individuella faktorer.Tre olika sjukvårdsenheter; en akutsjukvårdsenhet, en barnsjukvårdsenhet och en operationssjukvårdsenhet, samtliga vid ett större sjukhus, ingår i studien. 17 undersköterskor och 5 vårdenhetschefer har intervjuats.Avhandlingen visar att undersköterskor som verkar inom akut eller traumatisk sjukvård också har ett varierat och oförutsett arbete, vilket ger dem goda möjligheter till lärande och utveckling. Vidare har undersköterskor som arbetar med uppgifter inom vårdens kärnverksamhet möjlighet att lära i arbetet. Avgörande i sammanhanget är att dessa arbetsuppgifter uppfattas som intressanta, meningsfulla och stimulerande. Lärande underlättas för de undersköterskor som arbetar vid en vårdenhet där de görs delaktiga i vårdarbetet och arbetsgemenskapen. Undersköterskor som arbetar tillsammans med andra yrkesgrupper kan ha möjlighet att lära i arbetet. Även delegering av arbetsuppgifter har betydelse för möjligheterna att lära. Avhandlingen visar också att undersköterskor kan hindras från att lära i arbetet om den sjuksköterska som de arbetar närmast (i vårdpar eller i team) inte tillåter dem att utföra vissa arbetsuppgifter. Det framkommer också att undersköterskor som saknar intresse, eller ork hindras från att lära och utvecklas i arbetet. Undersköterskor har begränsade möjligheter att delta i, och utvecklas genom formella läraktiviteter. Kursutbudet är litet och en del av de kurser som erbjuds rör inte vårdens kärnverksamhet.
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| 16. |
- Duenas Dobrowolski, Jan, et al.
(author)
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Experimental Study of Lubricating Grease Flow inside the Gap of a Labyrinth Seal Using Microparticle Image Velocimetry
- 2018
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In: Tribology Transactions. - : Taylor & Francis. - 1040-2004 .- 1547-397X. ; 61:1, s. 31-40
-
Journal article (peer-reviewed)abstract
- In this study, the flow of lubricating greases in a labyrinth seal geometry is studied using microparticle image velocimetry (µPIV). The aim is to evaluate the grease velocity distribution inside the gap of a labyrinth seal and to find a relationship between the grease consistency and the transferred speed from the rotating ring in order to choose the correct grease as a sealing medium. In addition, the grease flow characteristics are important for the understanding of fracture due to grease layer displacement. For these purposes, four greases with different rheological properties were used in µPIV experiments. It was found that the grease consistency plays a crucial role in speed development as well as the grease composition and presence of a slip effect at the grease–rotating wall interface.
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| 17. |
- Edlund, Lars-Erik, 1953-
(author)
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Aktuell litteratur om svenska dialekter
- 2006
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In: Svenska landsmål och svenskt folkliv. - Uppsala : Kungl. Gustav Adolfs Akademien för svensk folkkultur. - 0347-1837. ; , s. 127-138
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Journal article (other academic/artistic)
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Eriksson, Per-Erik, et al.
(author)
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Effects of cooperative procurement procedures on construction project performance : a conceptual framework
- 2011
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In: International Journal of Project Management. - : Elsevier BV. - 0263-7863 .- 1873-4634. ; 29:2, s. 197-208
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Journal article (peer-reviewed)abstract
- In this paper, we develop a testable holistic procurement framework that examines how a broad range of procurement related factors affects project performance criteria. Based on a comprehensive literature review, we put forward propositions suggesting that cooperative procurement procedures (joint specification, selected tendering, soft parameters in bid evaluation, joint subcontractor selection, incentive-based payment, collaborative tools, and contractor self-control) generally have a positive influence on project performance (cost, time, quality, environmental impact, work environment, and innovation). We additionally propose that these relationships are moderated or mediated by the collaborative climate (i.e. the trust and commitment among partners) in the project and moderated by the overall project characteristics (i.e. how challenging the project is in terms of complexity, customization, uncertainty, value/size, and time pressure). Based on our contribution, future research can test the framework empirically to further increase the knowledge about how procurement factors may influence project performance.
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| 22. |
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| 23. |
- Fridell, Erik, 1963, et al.
(author)
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Investigation of NOx storage catalysts
- 1997
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In: 4th International Congress on Catalysis and Automotive Pollution Control (CAPoC4) in Brussels, Belgium, April 9-11, 1997.
-
Conference paper (peer-reviewed)
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| 24. |
- Fridell, Erik, 1963, et al.
(author)
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Investigations of NOx storage catalysts
- 1998
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In: Studies in Surface Science and Catalysis. - 0167-2991. ; 116, s. 537-547
-
Journal article (peer-reviewed)abstract
- NOx storage catalysts are used to reduce nitrogen oxides from lean-burn vehicles. The nitrogen oxides are stored in the catalyst during lean conditions and subsequently released and reduced during short periods of rich conditions. In the present study, we systematically investigate the sequence of elementary steps in the NOx reduction cycle, and the extent to which these steps influence the maximum NOx, reduction potential of the catalyst. As a model system, we use barium oxide as the NOx, storing compound in a Pt/Rh/Al2O3 system. Kinetics of NO oxidation, NO and NO2 adsorption, NO and NO2 release and reduction are studied under controlled conditions with systematic variations of temperature, gas composition, and storing/release times. The transient experiments comprise a storing phase using a lean NO/C3H6/O2/N2 gas mixture, and a regenerating phase where the O2 now is turned off. Experimentally, a significant amount of NOx is found to be stored in the Ba-containing material. A maximum in NOx storage is observed around 380 degrees C. For most of the experiments, there are clear NO and NO2 desorption peaks upon switching from the storing to the regeneration phase. TPD studies of NO and NO2 reveal a significant difference between prereduced and pre-oxidised samples where the former produce predominantly N2 and N2O at around 200 degrees C while NO and O2 desorb from the latter around 500 degrees C. In situ FTIR spectra show nitrate peaks in the region 1300-1400 cm(-1) when NOx is stored under lean conditions.
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| 25. |
- Fridell, Erik, 1963, et al.
(author)
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Model studies of NOx storage
- 2001
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In: ENVICAT2001, Amolfi, Italy, May 2-6, 2001.
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Conference paper (peer-reviewed)
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| 26. |
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| 27. |
- Fridell, Erik, 1963, et al.
(author)
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Model studies of NOx storage and sulphur deactivation of NOx storage catalysts
- 2001
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In: Topics in Catalysis. - 1572-9028 .- 1022-5528. ; 16-17:1-4, s. 133-137
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Journal article (peer-reviewed)abstract
- The storage of NOx under lean conditions in model NOx storage catalysts as well as the deactivation by sulphur have been studied. We find that NO2 plays an important role in the storage mechanism as an oxidising agent. Two different mechanisms for this are discussed: the formation of surface peroxides and the oxidation of nitrites to nitrates, FTIR studies show that NOx is stored as surface nitrates, The sulphur deactivation is found to be more severe when SO2 is added during the rich phase than when SO2 is added during the lean period. FTIR shows the formation of bulk sulphates both under lean and rich conditions.
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| 28. |
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| 29. |
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| 30. |
- Fridell, Erik, 1963, et al.
(author)
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NOx storage in barium-containing catalysts
- 1999
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In: Journal of Catalysis. - : Elsevier BV. - 0021-9517 .- 1090-2694. ; 183:2, s. 196-209
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Journal article (peer-reviewed)abstract
- The effect of key parameters on the characteristics of barium oxide-based NOx storage catalysts was systematically investigated. Model Pt/BaO/Al2O3, BaO/Al2O3, Pt–Rh/Al2O3, and Pt–Rh/BaO/Al2O3 catalysts were prepared and evaluated with respect to NOx storage capacity using transient flow reactor studies, temperature-programmed desorption studies (TPD), and in situ Fourier transform infrared (FTIR) absorption spectroscopy. The influence of temperature, storage and regeneration times, NOx source (NO or NO2), oxygen concentration, reducing agent (C3H6, C3H8, CO, or H2), and carbon dioxide concentration onNOx storage capacity was studied. Significant amounts of NOx were found to be stored in the catalysts containing both barium oxide and noble metals. For these catalysts the following observations were made: (1) maximum NOx storage was observed at about 380C;(2) around this temperature no significant differences between NO and NO2 on NOx storage capacity could be observed;(3) a slow increase in stored NOx could be observed with increasing oxygen concentration during the lean phase;(4) significant NOx desorption peaks, mainly of NO, were observed immediately after the switch from lean to rich conditions; and (5) at about 380±C the in situ FTIR spectra show characteristic nitrate peaks in the region 1300–1400 cm¡1 when NOx was stored under lean conditions and isocyanate peaks around 2230 cm-1 when the catalysts were regenerated under rich conditions in the presence of hydrocarbons. The step leading to stored NOx is believed to involve NO2 and the presence of atomic oxygen. During the rich period, the noble metal surfaces are probably reduced, leading to breakthrough peaks when NO desorbs.
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| 31. |
- Fridell, Erik, 1963, et al.
(author)
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The Mechanism for NOx Storage
- 2000
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In: Catalysis Letters. - 1572-879X .- 1011-372X. ; 66:1-2, s. 71-74
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Journal article (peer-reviewed)abstract
- The mechanisms for storing of NOx in platinum-barium-alumina catalysts during lean-rich transients are investigated. Oxidation of NO to NO2 is found to be an important step. NO2 is found to be important for oxidation of the catalyst or of nitrites to form nitrates. NOx is then stored in the form of surface nitrates. FTIR studies show no formation of bulk nitrates in these experiments.
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| 32. |
- Green, Torbjörn M., et al.
(author)
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A new method to visualize grease flow in a double restriction seal using microparticle image velocimetry
- 2011
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In: Tribology Transactions. - : Informa UK Limited. - 1040-2004 .- 1547-397X. ; 54, s. 784-792
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Journal article (peer-reviewed)abstract
- A new method to visualize and quantify grease flow in between two sealing lips or, in general, a double restriction seal is presented. Two setups were designed to mimic different types of seals; that is, a radial and an axial shaft seal. The flow of the grease inside and in between the sealing restrictions was measured using microparticle image velocimetry. The results show that grease flow due to a pressure difference mainly takes place close to the rotating shaft surface with an exponentially decaying velocity profile in the radial direction. Consequently, contaminants may be captured in the stationary grease at the outer radius, which explains the sealing function of the grease.
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| 33. |
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| 34. |
- Gülen, Theo, et al.
(author)
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Distinct plasma biomarkers confirm the diagnosis of mastocytosis and identify increased risk of anaphylaxis
- 2021
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In: Journal of Allergy and Clinical Immunology. - : Elsevier. - 0091-6749 .- 1097-6825. ; 148:3, s. 889-894
-
Journal article (peer-reviewed)abstract
- Background: Mastocytosis encompasses a heterogeneous group of disorders characterized by accumulation of clonal mast cells (MCs) in the skin and/or internal organs. Patients typically present with a broad variety of recurrent mediator-related clinical symptoms, including severe anaphylaxis. However, not all patients with mastocytosis experience anaphylactic reactions.Objective: We sought to identify disease-specific biomarkers in plasma that could be used to predict patients with mastocytosis with increased risk of anaphylaxis.Methods: Nineteen patients (>_18 years) and 2 control groups (11 subjects with allergic asthma and 13 healthy volunteers without history of atopy) were recruited. In total, 248 plasma proteins were analyzed by Proximity Extension Assay using Olink Proseek Multiplex panels.Results: We identified 4 novel proteins, in addition to tryptase, E-selectin, adrenomedullin, T-cell immunoglobulin, and mucin domain 1, and CUB domain-containing protein 1/CD138 to be significantly increased in patients with mastocytosis compared with both patients with asthma and healthy controls. Furthermore, we investigated whether we could discriminate between patients with mastocytosis with or without anaphylaxis. In addition to tryptase, we identified 3 novel proteins, that is, allergin-1, pregnancy-associated plasma protein-A, and galectin-3, with significantly different levels in patients with mastocytosis with anaphylaxis compared with those without anaphylaxis.Conclusions: Newly identified proteomic biomarkers may be used to predict patients with mastocytosis with increased risk of anaphylaxis.
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| 35. |
- Han, Hongya, et al.
(author)
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Human 15-lipoxygenase-1 is a regulator of dendritic-cell spreading and podosome formation
- 2017
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In: The FASEB Journal. - : FEDERATION AMER SOC EXP BIOL. - 0892-6638 .- 1530-6860. ; 31:2, s. 491-504
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Journal article (peer-reviewed)abstract
- Dendritic cells (DCs) involved in proinflammatory immune responses derive mainly from peripheral monocytes, and the cells subsequently mature and migrate into the inflammatory micromilieu. Here we report that suppressing of 15-lipoxygenase-1 led to a substantial reduction in DC spreading and podosome formation in vitro. The surface expression of CD83 was significantly lower in both sh-15-lipoxygenase-1 (15-LOX-1)-transduced cells and DCs cultivated in the presence of a novel specific 15-LOX-1 inhibitor. The T-cell response against tetanus-pulsed DCs was only affected to a minor extent on inhibition of 15-LOX-1. In contrast, endocytosis and migration ability of DCs were significantly suppressed on 15-LOX-1 inhibition. The expression of 15-LOX-1 in DCs was also demonstrated in affected human skin in atopic and contact dermatitis, showing that the enzyme is indeed expressed in inflammatory diseases in vivo. This study demonstrated that inhibiting 15-LOX-1 led to an impaired podosome formation in DCs, and consequently suppressed antigen uptake and migration capacity. These results indicated that 15-LOX-1 is a potential target for inhibiting the trafficking of DCs to lymphoid organs and inflamed tissues and decreasing the inflammatory response attenuating symptoms of certain immunologic and inflammatory disorders such as dermatitis.-Han, H., Liang, X., Ekberg, M., Kritikou, J. S., Brunnstro " m, angstrom., Pelcman, B., Matl, M., Miao, X., Andersson, M., Yuan, X., Schain, F., Parvin, S., Melin, E., Sjoberg, J., Xu, D., Westerberg, L. S., Bjorkholm, M., Claesson, H.- E. Human 15-lipoxygenase- 1 is a regulator of dendritic-cell spreading and podosome formation.
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| 36. |
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| 37. |
- Kluge, Jimmy Nils Erik, et al.
(author)
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Modelling heat transfer inside an autoclave: Effect of radiation
- 2016
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In: Journal of reinforced plastics and composites (Print). - : SAGE Publications. - 0731-6844 .- 1530-7964. ; 35:14, s. 1126-1142
-
Journal article (peer-reviewed)abstract
- In this work, computational fluid dynamics simulations are performed to predict the temperature distribution on a part during an autoclave run. Data from an experimental study are used as input to the simulations and also for comparison with the numerical results. A conjugate heat transfer approach was used for the simulations, where best agreement with experiments was obtained from the simulation that included thermal radiation and utilized an experimentally obtained velocity profile as inlet velocity. A yet more detailed inlet velocity profile and more advanced turbulent model could result in an even better agreement.
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| 38. |
- Lekamlage, Charitha Dissanayake, et al.
(author)
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Mini-DDSM : Mammography-based Automatic Age Estimation
- 2020
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In: ACM International Conference Proceeding Series. - New York, NY, USA : Association for Computing Machinery. - 9781450389044 ; , s. 1-6
-
Conference paper (peer-reviewed)abstract
- Age estimation has attracted attention for its various medical applications. There are many studies on human age estimation from biomedical images. However, there is no research done on mammograms for age estimation, as far as we know. The purpose of this study is to devise an AI-based model for estimating age from mammogram images. Due to lack of public mammography data sets that have the age attribute, we resort to using a web crawler to download thumbnail mammographic images and their age fields from the public data set; the Digital Database for Screening Mammography. The original images in this data set unfortunately can only be retrieved by a software which is broken. Subsequently, we extracted deep learning features from the collected data set, by which we built a model using Random Forests regressor to estimate the age automatically. The performance assessment was measured using the mean absolute error values. The average error value out of 10 tests on random selection of samples was around 8 years. In this paper, we show the merits of this approach to fill up missing age values. We ran logistic and linear regression models on another independent data set to further validate the advantage of our proposed work. This paper also introduces the free-access Mini-DDSM data set. © 2020 ACM.
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| 39. |
- Li, Jinxia, et al.
(author)
-
Design of test rig for visualizations of cylindrical shear and pressure driven Couette flow using μPIV
- 2014
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Conference paper (peer-reviewed)abstract
- Couette flow is often encountered in concentric cylinder application such as rheometers etc. Being able to visualize such flows is of interest both from a fundamental point of view to understand the dynamics of complex fluids, but also in specific applications such as lubricants flowing through seal geometries. In this study a concentric cylinder test rig has been designed to visualize Couette flow in both radial and axial direction using micro Particle Image Velocimetry. The rig allows for control of the flow motion; the rotating inner cylinder creates a peripheral flow and an applied pressure in the axial direction creates a pressure driven flow. Thus, a single flow direction or a combination of directions can be analyzed. To demonstrate the technique a flow of a non-Newtonian shear thinning fluid in the form of lubricating grease was investigated and discussed. It is found that it is possible to capture the yield behavior of the grease, with regions of fully and partially yielded flow visible. The influence of temperature creep flow is also presented. Grease with both high and low yield stress are measured and compared could be measured and compared in a pocket with variable size. Furthermore, non-homogeneous effects such as shear banding and wall slip can be visualized. The test rig has thus a high potential to investigate the influence of wall material and wettability between fluids and the housing on the flow and wall slip behavior as long as the fluid is optically transparent.
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| 40. |
- Li, Jinxia, et al.
(author)
-
Experimental study of free surface grease flow subjected to centrifugal forces
- 2014
-
Conference paper (peer-reviewed)abstract
- In order to improve the understanding of grease flow in various applications such as gears, seals and rolling bearings, the free surface flow of different greases under different running conditions has been investigated. A rotating disc has been used to study grease flow as the grease was subjected to a centrifugal force. The grease flow and mass loss was measured for greases with different rheology on different surfaces and with surface textures. It is shown that the speed at which grease starts to move is mostly determined by grease type and yield stress, while the impact of the surface material and roughness is less pronounced. The mass loss is shown to be influenced both by the rheology of the grease and the surface material
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| 41. |
- Li, Jinxia, et al.
(author)
-
Grease free surface flow on a rotating plate
- 2014
-
Conference paper (peer-reviewed)abstract
- In order to improve the understanding of grease flow in various applications such as gears, seals and rolling element bearings, free surface flow of different greases under different running conditions has been investigated. A rotating disc has been used to study grease flow as the grease is subjected to a centrifugal force. The adhesion and mass loss was detected for greases with different rheology on different surfaces and surface textures. It is shown that the speed at which grease starts to move is mostly determined by grease type, yield stress and bleeding properties rather than surface material. Also, the surface adhesion is shown to be influenced both by the rheology of the grease and the surface material.
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| 42. |
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| 43. |
- Li, Jinxia, et al.
(author)
-
Lubricating Grease Shear Flow and Boundary Layers in a Concentric Cylinder Configuration
- 2015
-
Conference paper (peer-reviewed)abstract
- Grease is extensively used to lubricate various machine elements such as rolling bearings, seals, and gears. Understanding the flow dynamics of grease is relevant for the prediction of grease distribution for optimum lubrication and for the migration of wear and contaminant particles. In this study, grease flow is visualized using micro Particle Image Velocimetry (μPIV). The experimental setup includes a concentric cylinder configuration with a rotating shaft to simulate the grease flow in a double restriction seal geometry with two different grease pocket sizes. It is shown that the grease is partially yielded in the large grease pocket geometry and fully yielded in the small grease pocket. For the small grease pocket, it is shown that three distinct grease flow layers are present: a high shear rate region close to the stationary wall, a bulk flow layer, and a high shear rate boundary region near the rotating shaft. The grease shear thinning behavior and its wall slip effects have been identified. The μPIV experimental results have been compared with a numerical model for both the large and small gap size. It is shown that the flow is close to one-dimensional in the center of the small pocket. A one-dimensional analytical model based on the Herschel-Bulkley rheology model has been developed, showing good agreement with the measured velocity profiles in the small grease pocket. Furthermore, wall slip effects and shear banding are observed, where the latter imply that using the assumption of uniform shear in conventional concentric cylinder rheometers may result in erroneous rheological results.
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| 44. |
- Li, Jinxia, et al.
(author)
-
Lubricating grease shear flow and boundary layers in a concentric cylinder configuration
- 2013
-
In: Proceedings of the 3rd International Tribology Symposium of IFoMM (International Federation for the Promotion of Mechanism and Machine Science), Luleå, March 19-21, 2013.
-
Conference paper (peer-reviewed)abstract
- Grease is extensively used to lubricate various machine elements such as rollingbearings, seals, and gears. Understanding the flow dynamics of grease is relevant forthe prediction of the grease distribution for optimum lubrication and the migration ofwear- and contaminant particles. In this study grease flow is visualized using themethod of micro Particle Image Velocimetry; the experimental setup comprises aconcentric cylinder with rotating shaft to simulate the grease flow in a DoubleRestriction Seal (DRS) geometry with two different grease pocket heights. It is shownthat grease may be partially yielded in the large grease pocket geometry and fullyyielded in the small grease pocket geometry. For the small grease pocket geometry, itis shown that three distinct grease flow layers are present: a high shear rate regionclose to the stationary wall, a bulk flow layer, and a high shear rate boundary regionnear the rotating shaft. The grease shear thinning behaviour and its wall slip effectshave been detected and discussed.
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| 45. |
- Li, Jinxia, et al.
(author)
-
Lubricating grease shear flow and boundary layers in a concentric cylinder configuration
- 2014
-
In: Tribology Transactions. - : Informa UK Limited. - 1040-2004 .- 1547-397X. ; 57:6, s. 1106-1115
-
Journal article (peer-reviewed)abstract
- Grease is extensively used to lubricate various machine elements such as rolling bearings, seals, and gears. Understanding the flow dynamics of grease is relevant for the prediction of grease distribution for optimum lubrication and for the migration of wear and contaminant particles. In this study, grease flow is visualized using microparticle image velocimetry (μPIV). The experimental setup includes a concentric cylinder configuration with a rotating shaft to simulate the grease flow in a double restriction seal geometry with two different grease pocket sizes. It is shown that the grease is partially yielded in the large grease pocket geometry and fully yielded in the small grease pocket. For the small grease pocket, it is shown that three distinct grease flow layers are present: a high shear rate region close to the stationary wall, a bulk flow layer, and a high shear rate boundary region near the rotating shaft. The grease shear thinning behavior and its wall slip effects have been identified. The μPIV experimental results have been compared with a numerical model for both the large and small gap size. It is shown that the flow is close to one-dimensional in the center of the small pocket. A one-dimensional analytical model based on the Herschel-Bulkley rheology model has been developed, showing good agreement with the measured velocity profiles in the small grease pocket. Furthermore, wall slip effects and shear banding are observed, where the latter imply that using the assumption of uniform shear in conventional concentric cylinder rheometers may result in erroneous rheological results.
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| 46. |
- Li, Jinxia, et al.
(author)
-
µPIV measurement of grease velocity profiles in channels with two different types of flow restrictions
- 2012
-
In: Tribology International. - : Elsevier BV. - 0301-679X .- 1879-2464. ; 54, s. 94-99
-
Journal article (peer-reviewed)abstract
- Grease is commonly used to lubricate various machine components such as rolling bearings and seals. In this paper the flow of lubricating grease passing restrictions is described. Such flow occurs in rolling bearings during relubrication events where the grease is flowing in the transverse (axial) direction through the bearing and is hindered by guide rings, flanges et cetera, as well as in seals where transverse flow occurs, for example during so-called breathing caused by temperature fluctuations in the bearing. This study uses a 2D flow model geometry consisting of a wide channel with rectangular cross-section and two different types of restrictions to measure the grease velocity vector field, using the method of Micro Particle Image Velocimetry. In the case of a single restriction, the horizontal distance required for the velocity profile to fully develop is approximately the same as the height of the channel. In the corner before and after the restriction, the velocities are very low and part of the grease is stationary. For the channel with two flow restrictions, this effect is even more pronounced in the “pocket” between the restrictions. Clearly, a large part of the grease is not moving. This condition particularly applies to the cases with a low-pressure drop and where high consistency grease is used. In practice this means that grease is not replaced in such “corners” and that some aged/contaminated grease will remain in seal pockets.
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| 47. |
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| 48. |
- Ling, Erik, et al.
(author)
-
Mot ett hållbart energisystem : Fyra förändringsmodeller
- 2001
-
Reports (other academic/artistic)abstract
- Syftet med denna studie är att undersöka hur förändringsprocesser mot ett hållbart energisystem går till i verkligheten. Fokus läggs på strategiska förändringsprocesser inom den kommunala sektorn och på att identifiera centrala drag som är avgörande för förändringsprocessens resultat.
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| 49. |
- Ling, Erik, et al.
(author)
-
Mot ett hållbart energisystem: fyra förändringsmodeller : huvudrapport
- 2002
-
Reports (other academic/artistic)abstract
- The public sector in Sweden has charged its institutional structures with a new goal for societal development under the rubric "The Sustainable Sweden". This has been the result of international agreements that Sweden has entered into and domestic debates concerning the need for a sustainable development. The interaction between the public sector and the development of the energy system has entered a new phase. At the same time market reorientation has radically changed the public sector's possibilities to directly control the implementation of the sustainability goals in the energy system. Influence through ownership and the direct political control that this entailed has more or less been voluntarily phased out during recent years by governmental and municipal organizations. The desire for a change towards sustainable development has, however, meant that the public sector needs new ways to initiate, push for or support processes of change within the energy system in its new, multifaceted shape. Therefore in this study we focus on the energy sector and the possibilities to development steering methods for a sustainable energy system by: - Studying processes of change in different parts of the energy system with the purpose of identifying different forms for strategic change, - Describing the pressures, barriers and possibilities which are made visible in these processes, - Discussing and developing methods for managing and steering the processes of change.
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| 50. |
- Milberg, Per, et al.
(author)
-
Flower abundance and vegetation height as predictors fornectar-feeding insect occurrence in Swedish semi-natural grasslands
- 2016
-
In: Agriculture, Ecosystems & Environment. - : Elsevier. - 0167-8809 .- 1873-2305. ; 230, s. 47-54
-
Journal article (peer-reviewed)abstract
- With steadily shrinking areas of species-rich semi-natural grasslands in Europe, the management of theremaining fragments becomes ever more crucial for the preservation of key elements of biodiversity inthe agricultural landscape. Detailed knowledge about species-wise, as well as group-wise, relationshipscan provide guidelines for conservation management and a basis for predictions about differentmanagement scenarios. In the present study, we related the occurrence of species of bumblebees (N = 12),butterflies (31) and day-flying moths (4) and their total richness in 424 sites in southern Sweden to threegrass sward attributes, (i)flower abundance, (ii) height of the grass sward and (iii) within-site variation inheight of vegetation. The abundance of nectar-bearingflowers proved overall the best predictor ofrichness and in most of the occurrence-based species-wise models. However, both high grass swardheight and high variation in grass sward height contributed significantly to species richness andoccurrence of individual species. There was a tendency for bumblebees to respond less positively toflower abundance and vegetation height than butterflies and moths. One expectation was that grasslandspecialists, red-listed species, or species decreasing in other part of Europe, would be more responsive totall vegetation orflower abundance but there was no support for this in the data. Hence, managementstrategies that promote common species will also benefit all, or most of, the rare ones as well.
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