| 1. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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| 2. |
- Jiang, Xiao, et al.
(författare)
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Highly Efficient Solid-State Dye-Sensitized Solar Cells Based on Triphenylamine Dyes
- 2011
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 21:15, s. 2944-2952
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Tidskriftsartikel (refereegranskat)abstract
- Two triphenylamine-based metal-free organic sensitizers, D35 with a single anchor group and M14 with two anchor groups, have been applied in dye-sensitized solar cells (DSCs) with a solid hole transporting material or liquid iodide/triiodide based electrolyte. Using the molecular hole conductor 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)9,9'-spirobifluorene (spiro-OMeTAD), good overall conversion efficiencies of 4.5% for D35 and 4.4% for M14 were obtained under standard AM 1.5G illumination (100 mW cm(-2)). Although M14 has a higher molar extinction coefficient (by similar to 60%) and a slightly broader absorption spectrum compared to D35, the latter performs slightly better due to longer lifetime of electrons in the TiO(2), which can be attributed to differences in the molecular structure. In iodide/triiodide electrolyte-based DSCs, D35 outperforms M14 to a much greater extent, due to a very large increase in electron lifetime. This can be explained by both the greater blocking capability of the D35 monolayer and the smaller degree of interaction of triiodide (iodine) with D35 compared to M14. The present work gives some insight into how the molecular structure of sensitizer affects the performance in solid-state and iodide/triiodide-based DSCs.
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| 3. |
- Karlsson, Anna, 1967, et al.
(författare)
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Different glycosphingolipid composition in human neutrophil subcellular compartments.
- 2001
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Ingår i: Glycoconjugate journal. - 0282-0080. ; 18:3, s. 231-43
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Tidskriftsartikel (refereegranskat)abstract
- The binding of a number of carbohydrate-recognizing ligands to glycosphingolipids and polyglycosylceramides of human neutrophil subcellular fractions (plasma membranes/secretory vesicles of resting and ionomycin-stimulated cells, specific and azurophil granules) was examined using the chromatogram binding assay. Several organelle-related differences in glycosphingolipid content were observed. The most prominent difference was a decreased content of the GM3 ganglioside in plasma membranes of activated neutrophils. Gangliosides recognized by anti-VIM-2 antibodies were detected mainly in the acid fractions of azurophil and specific granules. Slow-migrating gangliosides and polyglycosylceramides with Helicobacter pylori-binding activity were found in all acid fractions. A non-acid triglycosylceramide, recognized by Gal(alpha)4Gal-binding Escherichia coli, was detected in the plasma membrane/secretory vesicles but not in the azurophil and specific granules. Although no defined roles of glycosphingolipids have yet been conclusively established with respect to neutrophil function, the fact that many of the identified glycosphingolipids are stored in granules, is in agreement with their role as receptor structures that are exposed on the neutrophil cell surface upon fusion of granules with the plasma membrane. Accordingly, we show that neutrophil granules store specific carbohydrate epitopes that are upregulated to the plasma membrane upon cell activation.
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| 4. |
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| 5. |
- Karlsson, Johan, et al.
(författare)
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Shape Modeling by Optimising Description Length Using Gradients and Parameterisation Invariance
- 2012
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Ingår i: Analysis for Science, Engineering and Beyond, The Tribute Workshop in Honour of Gunnar Sparr held in Lund, May 8-9, 2008. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783642202353 - 9783642202360 ; 6, s. 51-91
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In Statistical Shape Modeling, a dense correspondence between the shapes in the training set must be established. Traditionally this has been done by hand, a process that commonly requires a lot of work and is difficult, especially in 3D. In recent years there has been a lot of work on automatic construction of Shape Models. In recent papers (Davies et al., Medical Image Computing and Computer-Assisted Intervention MICCAI’2001, pp. 57–65, 2001; Davies et al., IEEE Trans. Med. Imaging. 21(5):525–537 2002; Kotcheff and Taylor, Med. Image Anal. 2:303–314 1998) Minimum Description Length, (MDL), is used to locate a dense correspondence between shapes. In this paper the gradient of the description length is derived. Using the gradient, MDL is optimised using steepest descent. The optimisation is therefore faster and experiments show that the resulting models are better. To characterise shape properties that are invariant to similarity transformations, it is first necessary to normalise with respect to the similarity transformations. This is normally done using Procrustes analysis. In this paper we propose to align shapes using the MDL criterion. The MDL based algorithm is compared to Procrustes on a number of data sets. It is concluded that there is improvement in generalisation when using MDL to align the shapes. In this paper novel theory to prevent the commonly occurring problem of clustering under correspondence optimisation is also presented. The problem is solved by calculating the covariance matrix of the shapes using a scalar product that is invariant to mutual reparameterisations. An algorithm for implementing the ideas is proposed and compared to Thodberg’s state of the art algorithm for automatic shape modeling. The suggested algorithm is more stable and the resulting models are of higher quality according to the generalisation measure and according to visual inspection of the specificity.
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| 6. |
- Mahdavi, Jafar, et al.
(författare)
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Helicobacter pylori SabA adhesin in persistent infection and chronic inflammation
- 2002
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Ingår i: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 297:5581, s. 573-578
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Tidskriftsartikel (refereegranskat)abstract
- Helicobacter pylori adherence in the human gastric mucosa involves specific bacterial adhesins and cognate host receptors. Here, we identify sialyl-dimeric-Lewis x glycosphingolipid as a receptor for H. pylori and show that H. pylori infection induced formation of sialyl-Lewis x antigens in gastric epithelium in humans and in a Rhesus monkey. The corresponding sialic acid-binding adhesin (SabA) was isolated with the "retagging" method, and the underlying sabA gene (JHP662/HP0725) was identified. The ability of many H. pylori strains to adhere to sialylated glycoconjugates expressed during chronic inflammation might thus contribute to virulence and the extraordinary chronicity of H. pylori infection.
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| 7. |
- Miller-Podraza, Halina, 1948, et al.
(författare)
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Novel binding epitope for Helicobacter pylori found in neolacto carbohydrate chains: structure and cross-binding properties.
- 2005
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Ingår i: The Journal of biological chemistry. - 0021-9258. ; 280:20, s. 19695-703
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Tidskriftsartikel (refereegranskat)abstract
- Helicobacter pylori is a bacterium that colonizes the stomach of a majority of the global human population causing common gastric diseases like ulcers and cancer. It has an unusually complex pattern of binding to various host glycoconjugates including interaction with sialylated, sulfated, and fucosylated sequences. The present study describes an additional binding epitope comprising the neolacto internal sequence of GlcNAcbeta3-Galbeta4GlcNAcbeta. The binding was detected on TLC plates as an interaction with a seven-sugar ganglioside of rabbit thymus. The glycolipid was purified and characterized as Neu5Gcalpha3Galbeta4GlcNAcbeta3Galbeta4GlcNAcbeta3-Galbeta4Glcbeta1Cer with less than 10% of the fraction carrying a repeated lacto (type-1) core chain, Galbeta3Glc-NAcbeta3Galbeta3GlcNAcbeta. After stepwise chemical and enzymatic degradation and structural analysis of products the strongest binder was found to be the pentaglycosylceramide GlcNAcbeta3Galbeta4GlcNAcbeta3Galbeta4Glcbeta1-Cer, whereas the hexa- and tetraglycosylceramides were less active, and the trihexosylceramide was inactive. Further studies revealed that the terminal GlcNAcbeta of the pentaglycosylceramide may be exchanged for either GalNAcbeta3, GalNAcalpha3, or Galalpha3 without loss of the activity. Calculated minimum energy conformers of these four isoreceptors show a substantial topographical similarity suggesting that this binding is a result of a molecular mimicry. Although the glycoconjugate composition of human gastric epithelial cells is not known in detail it is proposed that repeating N-acetyllactosamine units of glycoconjugates may serve as bacterial attachment sites in the stomach.
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| 8. |
- Rosén, Stefan, et al.
(författare)
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A multispecific saline-soluble lectin from the parasitic fungus Arthrobotrys oligospora. Similarities in the binding specificities compared with a lectin from the mushroom agaricus bisporus.
- 1996
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Ingår i: European journal of biochemistry / FEBS. - : Wiley. - 0014-2956 .- 1432-1033. ; 238:3, s. 830-7
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Tidskriftsartikel (refereegranskat)abstract
- Several fungi can express high levels of saline-soluble and low-molecular-mass lectins that bind to glycoproteins such as fetuin and different mucins but not bind to any monosaccharides. In this paper, we report the binding specificities of such a lectin (designated AOL) isolated from the nematophagous fungus Arthrobotrys oligospora. The results show that AOL is a multispecific lectin that interacts with the following ligands: (a) Several sulfated glycoconjugates including sulfatide, dextran sulfate, and fucoidan. The specificity of this binding was indicated by experiments showing that none of the tested neutral- and sialic-acid-containing glycolipids, chondroitin sulfates B and C, heparin, and polyvinyl sulfate bound to AOL; (b) Phosphatidic acid and phospatidylglycerol, two out of several tested phospholipids. (c) N-linked and O-linked sugar chains bound to intact fetuin. The involvement of such sugar structures was demonstrated by analyzing the binding of AOL to chemically deglycosylated (trifluoromethanesulfonic acid) fetuin. Treating fetuin with O-glycosidase and N-glycosidase indicated that AOL bound to Gal beta GaLNAc alpha-Ser/Thr and to some N-linked complex sugars, respectively. Further assays demonstrated that AOL could interact with several other glycoproteins containing O-linked and/or N-linked sugar chains. The observations that AOL did not bind to free N-linked sugars isolated from fetuin, or to fetuin treated with trypsin or pronase, or to any of the tested neoglycoproteins and glycolipids with neutral- or sialic acid-containing sugars, indicated that the sugar chains need to be bound to an intact peptide backbone to interact with AOL. We have recently shown that the deduced primary structure of AOL has a high similarity to the sequence of a saline-soluble lectin isolated from the mushroom Agaricus bisporus (ABL) (Rosén, S., Kata, M., Persson, Y., Lipniunas, P. H., Wikström, M., van den Hondel, C. A. M. J. J., van den Brink, J. M., Rask, L., Hedén L.-O. and Tunlid, A., see companion paper). It is well known that ABL binds to Gal beta 3GaLNAc alpha-Ser/Thr, and in this paper we demonstrate that ABL binds to sulfatide, phosphatidic acid, phospatidylglycerol, and possibly also to the same N-linked complex sugars as AOL. The above data indicate that AOL and ABL are members of a novel family of fungal lectins sharing similar primary structure and binding properties.
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| 9. |
- Yang, Lei, et al.
(författare)
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Comparing spiro-OMeTAD and P3HT hole conductors in efficient solid state dye-sensitized solar cells
- 2012
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Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 14:2, s. 779-789
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Tidskriftsartikel (refereegranskat)abstract
- Two hole conductor materials, spiro-OMeTAD and P3HT, were compared in solid-state dye-sensitized solar cells. Two organic dyes containing one anchor unit (D35) or two anchor units (M3) were used in the comparison. Absorbed photon to current conversion efficiency close to unity was obtained for the devices with spiro-OMeTAD. Energy conversion efficiencies of 4.7% and 4.9% were measured for the devices with spiro-OMeTAD and the dyes D35 and M3, respectively. For the devices using the P3HT hole conductor the results were rather different comparing the two dye molecules, with energy conversion efficiencies of 3.2% and 0.5% for D35 and M3, respectively. Photo-induced absorption measurements suggest that the regeneration of the dyes, and the polymer infiltration, is not complete using P3HT, while spiro-OMeTAD regenerates the dyes efficiently. However, the TiO(2)/D35/P3HT system shows rather high energy conversion efficiency and electrochemical oxidation of the dyes on TiO(2) indicates that D35 have a more efficient dye to dye hole conduction than M3, which thereby might explain the higher performance. The dye hole conduction may therefore be of significant importance for optimizing the energy conversion in such hybrid TiO(2)/dye/polymer systems.
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| 10. |
- Ytreberg, Agnes, et al.
(författare)
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God havsmiljö 2020 : Marin strategi för Nordsjön och Östersjön Del 3: Övervakningsprogram
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Havsmiljöförordningens övergripande mål är att upprätthålla eller uppnå en god miljöstatus i de svenska förvaltningsområdena Nordsjön och Östersjön till år 2020. En av uppgifterna i den första förvaltningsperioden är att fastställa övervakningsprogram.God miljöstatus baseras på ett ramverk av så kallade deskriptorer som anges i havsmiljödirektivet, det vill säga det EU-direktiv som i Sverige genomförs genom havsmiljöförordningen. Deskriptorerna beskriver god miljöstatus på en övergripande nivå för elva temaområden. Till varje deskriptor hör en rad kriterier som anger vad som ska ingå i en bedömning av miljöstatus. Utifrån de elva deskriptorerna har Sverige fastställt 13 övervakningsprogram. Sex program utgår ifrån olika biodiversitetsteman som berörs av en upp till tre deskriptorer, medan de övriga sju programmen utgår ifrån de deskriptorer som är mer inriktade mot belastning och miljöförändring.För varje program har ett antal underprogram föreslagits baserat på den nuvarande övervakningen och/eller planerad övervakning. Övervakning som ingår i programmen ska vara pågående och data ska vara tillgängliga. I programmen ingår nationell och regional miljöövervakning inklusive verksamhetsutövares recipientkontroll. Dessutom ingår annan typ av datainsamling som till exempel inventeringar av tumlare och uppgifter om omfattningen av mänskliga aktiviteter som orsakar belastning och miljöförändringar. Enligt havsmiljödirektivet ska övervakningen fånga upp tillstånd och miljöförändringar, belastning och omfattning av aktiviteterna som orsakar belastningen samt effekter av åtgärder. Eftersom nästa steg i havsförvaltningscykeln är att fastställa åtgärdsprogram kommer övervakning för att följa upp åtgärder att läggas till övervakningsprogrammen först under nästa förvaltningscykel.I beskrivningarna av programmen framgår hur den nuvarande övervakningen motsvarar de krav som ställs på dataunderlag genom havsmiljödirektivets bilaga III samt genom deskriptorer, kriterier, indikatorer och beslutade miljökvalitetsnormer. I dagens övervakning saknas bland annat tillräcklig övervakning för uppföljning av livsmiljöers tillstånd och utbredning. För marint avfall, buller och främmande arter saknas nationellt samordnad övervakning, men det görs regionala insatser och ett antal projekt har genomförts eller påbörjats för att öka kunskapen om hur övervakning bäst ska utformas. För de program som har pågående övervakning beskrivs utvecklingsbehoven för att förbättra underlaget för de återkommande tillståndsbedömningarna.Övervakningsprogrammet som fastställs under 2014 utgör således inte ett fast program för kunskapsinhämtning. Bristerna kommer att beaktas i det fortsatta genomförandet av havsmiljöförordningen där utveckling av indikatorer och övervakning kommer att ske kontinuerligt.
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