| 1. |
- Parvin, Farjana, et al.
(author)
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Divergent Age-Dependent Conformational Rearrangement within Aβ Amyloid Deposits in APP23, APPPS1, and AppNL-F Mice
- 2024
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In: ACS Chemical Neuroscience. - : AMER CHEMICAL SOC. - 1948-7193. ; 15:10, s. 2058-2069
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Journal article (peer-reviewed)abstract
- Amyloid plaques composed of fibrils of misfolded A beta peptides are pathological hallmarks of Alzheimer's disease (AD). A beta fibrils are polymorphic in their tertiary and quaternary molecular structures. This structural polymorphism may carry different pathologic potencies and can putatively contribute to clinical phenotypes of AD. Therefore, mapping of structural polymorphism of A beta fibrils and structural evolution over time is valuable to understanding disease mechanisms. Here, we investigated how A beta fibril structures in situ differ in A beta plaque of different mouse models expressing familial mutations in the A beta PP gene. We imaged frozen brains with a combination of conformation-sensitive luminescent conjugated oligothiophene (LCO) ligands and A beta-specific antibodies. LCO fluorescence mapping revealed that mouse models APP23, APPPS1, and App(NL-F) have different fibril structures within A beta-amyloid plaques depending on the A beta PP-processing genotype. Co-staining with A beta-specific antibodies showed that individual plaques from APP23 mice expressing A beta PP Swedish mutation have two distinct fibril polymorph regions of core and corona. The plaque core is predominantly composed of compact A beta 40 fibrils, and the corona region is dominated by diffusely packed A beta 40 fibrils. Conversely, the A beta PP knock-in mouse App(NL-F), expressing the A beta PP Iberian mutation along with Swedish mutation has tiny, cored plaques consisting mainly of compact A beta 42 fibrils, vastly different from APP23 even at elevated age up to 21 months. Age-dependent polymorph rearrangement of plaque cores observed for APP23 and APPPS1 mice >12 months, appears strongly promoted by A beta 40 and was hence minuscule in App(NL-F). These structural studies of amyloid plaques in situ can map disease-relevant fibril polymorph distributions to guide the design of diagnostic and therapeutic molecules.
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| 2. |
- Alexandersson, Per, et al.
(author)
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On the schur expansion of jack polynomials
- 2018
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In: 30th international conference on Formal Power Series and Algebraic Combinatorics, FPSAC 2018. - : Formal Power Series and Algebraic Combinatorics.
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Conference paper (peer-reviewed)abstract
- We present positivity conjectures for the Schur expansion of Jack symmetric functions in two bases given by binomial coefficients. Partial results suggest that there are rich combinatorics to be found in these bases, including Eulerian numbers, Stirling numbers, quasi-Yamanouchi tableaux, and rook boards. These results also lead to further conjectures about the fundamental quasisymmetric expansions of these bases, which we prove for special cases.
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| 3. |
- Alexandersson, Per, et al.
(author)
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Some conjectures on the Schur expansion of Jack polynomials
- 2021
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In: Journal of Combinatorics. - : INT PRESS BOSTON, INC. - 2156-3527 .- 2150-959X. ; 12:2, s. 215-233
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Journal article (peer-reviewed)abstract
- We present positivity conjectures for the Schur expansion of Jack symmetric functions in two bases given by binomial coefficients. Partial results suggest that there are rich combinatorics to be found in these bases, including Eulerian numbers, Stirling numbers, quasi-Yamanouchi tableaux, and rook boards. These results also lead to further conjectures about the fundamental quasisymmetric expansions of these bases, which we prove for special cases.
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| 4. |
- Asghar, Naveed, et al.
(author)
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Tick-borne encephalitis virus sequenced directly from questing and blood-feeding ticks reveals quasispecies variance.
- 2014
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In: PLOS ONE. - San Francisco, USA : Public Library of Science (PLoS). - 1932-6203. ; 9:7
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Journal article (peer-reviewed)abstract
- The increased distribution of the tick-borne encephalitis virus (TBEV) in Scandinavia highlights the importance of characterizing novel sequences within the natural foci. In this study, two TBEV strains: the Norwegian Mandal 2009 (questing nymphs pool) and the Swedish Saringe 2009 (blood-fed nymph) were sequenced and phylogenetically characterized. Interestingly, the sequence of Mandal 2009 revealed the shorter form of the TBEV genome, similar to the highly virulent Hypr strain, within the 3' non-coding region (3'NCR). A different genomic structure was found in the 3'NCR of Saringe 2009, as in-depth analysis demonstrated TBEV variants with different lengths within the poly(A) tract. This shows that TBEV quasispecies exists in nature and indicates a putative shift in the quasispecies pool when the virus switches between invertebrate and vertebrate environments. This prompted us to further sequence and analyze the 3'NCRs of additional Scandinavian TBEV strains and control strains, Hypr and Neudoerfl. Toro 2003 and Habo 2011 contained mainly a short (A)3C(A)6 poly(A) tract. A similar pattern was observed for the human TBEV isolates 1993/783 and 1991/4944; however, one clone of 1991/4944 contained an (A)3C(A)11 poly(A) sequence, demonstrating that quasispecies with longer poly(A) could be present in human isolates. Neudoerfl has previously been reported to contain a poly(A) region, but to our surprise the re-sequenced genome contained two major quasispecies variants, both lacking the poly(A) tract. We speculate that the observed differences are important factors for the understanding of virulence, spread, and control of the TBEV.
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| 5. |
- Auer, Anna, et al.
(author)
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The relevance of WHO injury surveillance guidelines for evaluation : learning from the Aboriginal Community-Centered Injury Surveillance System (ACCISS)and two institution-based systems
- 2011
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In: BMC Public Health. - : Springer Science and Business Media LLC. - 1471-2458. ; 11:744
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Journal article (peer-reviewed)abstract
- BACKGROUND: Over the past three decades, the capacity to develop and implement injury surveillance systems (ISS) has grown worldwide and is reflected by the diversity of data gathering environments in which ISS operate. The capacity to evaluate ISS, however, is less advanced and existing evaluation guidelines are ambiguous. Furthermore, the applied relevance of these guidelines to evaluate ISS operating in various settings is unclear. The aim of this paper was to examine how the World Health Organization (WHO) injury surveillance guidelines have been applied to evaluate systems operating in three different contexts. METHODS: The attributes of a good surveillance system as well as instructions for conducting evaluations, outlined in the WHO injury surveillance guidelines, were used to develop an analytical framework. Using this framework, a comparative analysis of the application of the guidelines was conducted using; the Aboriginal Community-Centered Injury Surveillance System (ACCISS) from Canada, the Shantou-Emergency Department Injury Surveillance Project (S-EDISP) from China, and the Yorkhill-Canadian Hospitals Injury Reporting and Prevention Program (Y-CHIRPP) imported from Canada and implemented in Scotland. RESULTS: The WHO guidelines provide only a basic platform for evaluation. The guidelines over emphasize epidemiologic attributes and methods and under emphasize public health and injury prevention perspectives requiring adaptation for context-based relevance. Evaluation elements related to the dissemination and use of knowledge, acceptability, and the sustainability of ISS are notably inadequate. From a public health perspective, alternative reference points are required for re-conceptualizing evaluation paradigms. This paper offers an ISS evaluation template that considers how the WHO guidelines could be adapted and applied. CONCLUSIONS: Findings suggest that attributes of a good surveillance system, when used as evaluation metrics, cannot be weighted equally across ISS. In addition, the attribute of acceptability likely holds more relevance than previously recognized and should be viewed as a critical underpinning attribute of ISS. Context-oriented evaluations sensitive to distinct operational environments are more likely to address knowledge gaps related to; understanding links between the production of injury data and its use, and the effectiveness, impact, and sustainability of ISS. Current frameworks are predisposed to disassociating epidemiologic approaches from subjective factors and social processes.
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| 6. |
- Berg, Lars-Erik, et al.
(author)
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Introduktion av värmekameror i undervisningen vid Lillerudsgymnasiet
- 2020
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Reports (other academic/artistic)abstract
- Vi har bedrivit en forskningscirkel med syfte att utvärdera värmekameran som visualiseringsteknik i olika ämnen på naturbruksprogrammet genom att planera, genomföra och reflektera kring lektionsupplägg, där elever har fått möjlighet att använda värmekameror med olika grad av styrning. Resultatet visar att värmekameran har många skilda tillämpningsområden inom lantbruk och djurhållning och kan användas i undervisningen som ett verktyg för elevers praktiska undersökningar av t.ex. djurs fysiologi, eller som ett mätinstrument då tillfälle ges, t.ex. för att studera juverbölder hos suggor eller temperaturökning när en skruv tar fel gäng. En utmaning i undervisningen är att finna en balans mellan öppenhet och styrning, där eleverna upplever att de har möjlighet att undersöka fenomen de själva är intresserade av, men utifrån ett etablerat, systematiskt arbetssätt. Sammanfattningsvis har vi upplevt användning av värmekameror som ett effektivt och intresseväckande sätt att konkretisera och individanpassa undervisningen på naturbruksprogrammet, vilket vi kan rekommendera andra lärare att prova.
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| 7. |
- Bidleman, Terry F., et al.
(author)
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Bromoanisoles and Methoxylated Bromodiphenyl Ethers in Macroalgae from Nordic Coastal Regions
- 2019
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In: Environmental Science. - London : Royal Society of Chemistry. - 2050-7887 .- 2050-7895. ; , s. 881-892
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Journal article (peer-reviewed)abstract
- Marine macroalgae are used worldwide for human consumption, animal feed, cosmetics and agriculture. In addition to beneficial nutrients, macroalgae contain halogenated natural products (HNPs), some of which have toxic properties similar to those of well-known anthropogenic contaminants. Sixteen species of red, green and brown macroalgae were collected in 2017–2018 from coastal waters of the northern Baltic Sea, Sweden Atlantic and Norway Atlantic, and analyzed for bromoanisoles (BAs) and methoxylated bromodiphenyl ethers (MeO-BDEs). Target compounds were quantified by gas chromatography-low resolution mass spectrometry (GC-LRMS), with qualitative confirmation in selected species by GC-high resolution mass spectrometry (GC-HRMS). Quantified compounds were 2,4-diBA, 2,4,6-triBA, 2′-MeO-BDE68, 6-MeO-BDE47, and two tribromo-MeO-BDEs and one tetrabromo-MeO-BDE with unknown bromine substituent positions. Semiquantitative results for pentabromo-MeO-BDEs were also obtained for a few species by GC-HRMS. Three extraction methods were compared; soaking in methanol, soaking in methanol–dichloromethane, and blending with mixed solvents. Extraction yields of BAs did not differ significantly (p > 0.05) with the three methods and the two soaking methods gave equivalent yields of MeO-BDEs. Extraction efficiencies of MeO-BDEs were significantly lower using the blend method (p < 0.05). For reasons of simplicity and efficiency, the soaking methods are preferred. Concentrations varied by orders of magnitude among species: ∑2BAs 57 to 57 700 and ∑5MeO-BDEs < 10 to 476 pg g−1 wet weight (ww). Macroalgae standing out with ∑2BAs >1000 pg g−1 ww were Ascophyllum nodosum, Ceramium tenuicorne, Ceramium virgatum, Fucus radicans, Fucus serratus, Fucus vesiculosus, Saccharina latissima, Laminaria digitata, and Acrosiphonia/Spongomorpha sp. Species A. nodosum, C. tenuicorne, Chara virgata, F. radicans and F. vesiculosus (Sweden Atlantic only) had ∑5MeO-BDEs >100 pg g−1ww. Profiles of individual compounds showed distinct differences among species and locations.
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| 8. |
- Bidleman, Terry F., et al.
(author)
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Sea-air exchange of bromoanisoles and methoxylated bromodiphenylethers in the Northern Baltic
- 2016
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In: Marine Pollution Bulletin. - : Elsevier. - 0025-326X .- 1879-3363. ; 112:1-2, s. 58-64
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Journal article (peer-reviewed)abstract
- Halogenated natural products in biota of the Baltic Sea include bromoanisoles (BAs) and methoxylated bromodiphenyl ethers (MeO-BDEs). We identified biogenic 6-MeO-BDE47 and 2'-MeO-BDE68 in Baltic water and air for the first time using gas chromatography - high resolution mass spectrometry. Partial pressures in air were related to temperature by: log p/Pa=m/T(K)+b. We determined Henry's law constants (HLCs) of 2,4-dibromoanisole (2,4-DiBA) and 2,4,6-tribromoanisole (2,4,6-TriBA) from 5 to 30°C and revised our assessment of gas exchange in the northern Baltic. The new water/air fugacity ratios (FRs) were lower, but still indicated net volatilization in May-June for 2,4-DiBA and May - September for 2,4,6-TriBA. The net flux (negative) of BAs from Bothnian Bay (38,000km2) between May - September was revised from -1319 to -532kg. FRs of MeO-BDEs were >1, suggesting volatilization, although this is tentative due to uncertainties in their HLCs and binding to dissolved organic carbon.
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| 9. |
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| 10. |
- Brorström-Lundén, Eva, et al.
(author)
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Screening of benzothiazoles, benzenediamines, dicyclohexylamine and benzotriazoles 2009
- 2012
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Reports (other academic/artistic)abstract
- En screeningundersökning av bensotiazoler, bensendiaminer, dicyclohexylamin och bensotriazoler har genomförts inom ramen för Naturvårdsvekets screeningprogram. Avsikten med en screeningundersökning är att bestämma koncentrationer av de utvalda substanserna i olika delar av den svenska miljön och därigenom belysa viktiga emissions- och transportvägar. Denna undersökning har genomförts i sammarbete med forskningsprogrammet ChEmiTecs “Organic Chemicals Emitted from Technosphere Articles" (www.chemitecs.se) finansierat av Naturvårdsverket. Målet med Chemitecs är att öka kunskapen om emissioner av organiska ämnen från varor. Resultaten ska stödja utvecklingen av svenska och europeiska handlingsprogram som ska minska riskerna med särskilt farliga ämnen. Bensotiazolerna MBT, CBS, DBS och DBD fanns i en eller flera av de undersökta provtyperna. Detektionsfrekvenserna varierade både mellan substanserna och provtyperna. Fördelningsmönstret påverkades troligen både av föreningarnas egenskaper, såsom kemisk stabilitet och tendens att fördelas mellan olika faser, och av användningen. MBT hade högst detektionsfrekvens medan de andra bensotiazolerna hittades mera sporadiskt. En viktig spridningsväg till miljön för MBT är via reningsverk vilket pekar på diffusa emissioner från konsumentprodukter. Förekomst i dagvatten indikerar trafik-relaterade emissioner. MBT och övriga bensotiazoler förekom främst i vattenmiljön medan lufttransport verkar vara av mindre betydelse. Bensendiaminen DPP hittades i vissa fall i till exempel ytvatten, dagvatten och reningsverksslam.DCHA var vanligt förekommande i alla provtyper utom i gröda. Att DCHA återfinns i luft och deposition indikerar att substansen emitteras till luft och att lufttransport är en viktig spridningsväg. Förekomsten i dagvatten och i jord visar att trafikrelaterade emissioner är viktiga. DCHA hittades emellertid inte i gröda insamlad i närheten av trafikerade vägar. En annan viktig spridningsväg för DCHA är via reningsverk vilket antyder diffusa emissioner från till exempel konsumentprodukter Bensotriazoler är vanligt förekommande i miljön både i bakgrundsmiljö och i urbana områden. Substanserna förekom i alla analyserade matriser: luft, deposition, ytvatten, sediment, jord och biota. Resultaten visade också att diffus spridning via reningsverk, deponier och dagvatten kan vara viktigt för förekomsten i miljön. Detta indikerar emissioner via användning av produkter. UVP är den bensotriazol som används mest följd av UV 328 och UV 327. Dessa substanser hittades också i högst koncentrationer.I en enkel riskbedömning för vattenmiljöns pelagiska ekosystem identifierades inga större risker, dvs halterna var generellt lägre än PNEC i ytvatten och i avloppsvatten med hänsyn till förväntad utspädning. DPP förekom dock i koncentrationer över PNEC i Viskan. Koncentrationen av DPP och DCHA i outspätt avloppsvatten överskred vid några tillfällen PNEC. Inga toxicitets eller ekotoxicitetsdata har hittats för någon av benzotriazolerna i tillgänglig litteratur. Några riskbedömningar för dessa har därför inte utförts.
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