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Oxidation of veratryl alcohol with lignin peroxidase and nanoscale photosystemsPedersen, Nicolai January 2018 (has links)
No description available.
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DNA-analys och idemtifikation : En studie om olika metoder för DNA-analys som används för identifikation av mänskliga skelettdelarPobric, Dzenana January 2018 (has links)
No description available.
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Total Synthesis of Viniferifuran andDehydroampelopsin B AnaloguesKrzyzanowski, Adrian January 2018 (has links)
No description available.
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Biophysical analysis of PS II – LHCII supercomplex : Understanding the LHCII phosphorylation-dependent dynamics along the thylakoid membraneGRAÇA, André January 2018 (has links)
No description available.
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Analysis of Small Molecules Designed to Target G-quadruplex DNA StructuresRomell, Tajanena January 2017 (has links)
No description available.
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Identification of volatile organic compounds (VOC) and organophosphate flame retardants (OPFR) in building materialsDuberg, Daniel January 2017 (has links)
Humans today spend most of their time in various indoor settings such as housing, schools and workplaces. The quality of the indoor environment is therefore of great significance for our wellbeing. However, it has been suggested that the indoor environment contains over 6000 organic compounds, such as various volatile organic compounds (VOC). Around 500 of these compounds is believed to be due to emissions from different surrounding building materials such as insulation, plastic film, sealants and flooring. This study targeted building materials from three low energy preschools that were sampled and analyzed for emissions of VOCs and nine different organophosphate flame retardant compounds (OPFR) using a gas chromatograph coupled to a mass spectrometer (GC/MS). Low energy buildings are buildings that is particularly air tight to be so energy efficient as possible. The study uses a qualitative approach and therefore mainly identifies possible contribution from building materials to indoor environment. More than 100 different VOCs was identified and the most noticeable were meta-, ortho- and para-xylene, toluene, n-hexane and propylene glycol, all but the last compound is associated with hazardous health effects. The building materials that emitted the largest amounts of VOCs was sealants and adhesives. Linoleum flooring and acrylic was also large emitters. Tris(1-chloro-2-propyl) phosphate (TCIPP) were identified in all samples and all nine targeted OPFR compounds were identified in the various material samples and dust samples. T-Flex tape and plastic film was the sample materials that emitted most OPFR compounds.
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Trophic transfer of per- and polyfluoroalkyl substances (PFASs) by glacial relicts in Lake Vättern, Sweden / Trofisk transport av per- och polyfluoreradealkylsubstanser (PFAS) via glacialrelikter i Vättern, SverigeBergman, Malin January 2017 (has links)
The aim with the study was to assess if glacial relict amphipods constitute as vectors of transport of per- and polyfluoroalkyl substances (PFASs) in the Arctic char food web in Lake Vättern, Sweden. Sediment, surface water and biota samples were analysed for PFASs using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and stable isotope analysis of δ 13C and δ15N was performed on sediments and biota samples. Sediment samples (n=3) were suggested to have PFASs originating from different sources. Generally low concentrations were detected in sediment (sum of all detected PFASs were 2.7 ng/g in St. Aspön, 2.9 ng/g in Visingsö and 0.6 ng/g in Omberg, reported in dry weight), compared to biota and several water samples. The PFAS distribution and concentrations in the samples representing St. Aspön and Visingsö deviated from the third sample from Omberg, which was further evidenced by stable isotope analysis. The average concentration of all detected PFASs in the potentially low contaminated samples was 6 ng/L, while it was 5900 ng/L in the potentially aqueous film forming foam (AFFF) contaminated samples. Surface water samples from Jönköping airport and Kärnebäcken measured concentrations of linear perfluorooctane sulfonate (L-PFOS) that all exceeded the Annual Average Environmental Quality Standard (AA-EQS) value of 0.65 ng/L of PFOS in freshwater (fire pond: 14 000 ng/L, ditch: 600 ng/L, Sandserydsån: 160 ng/L, Kärnebäcken: 150 ng/L). A reference sample that was assumed to represent diffuse sources showed similar distribution of PFASs as in several estuaries around Lake Vättern. Since the surface area of Lake Vättern is large (1900 km2), atmospheric deposition is suggested as one of the major contamination sources. This should be further investigated to better assess the local environmental burden. Trophic magnification factors (TMFs) calculated for L-PFOS, perfluorononaoate (PFNA) and perfluorotridecanoate (PFTrDA) were > 1, indicating biomagnification to higher trophic levels. Among all detected PFASs in biota samples, L-PFOS was the most prominent component (58 %), followed by PFTrDA (20 %), PFNA (6.7 %), perfluoroundecanoate (PFUnDA) (5.3 %), perfluorodecanoate (PFDA) (4.9 %) and perfluorooctanoate (PFOA) (2.9 %). Highest concentrations of all targeted compounds (ΣPFAS 220 ng/g) were detected in Monoporeia, the smallest of amphipods. Contamination profiles of perfluorinated carboxylates (PFCAs) showed similar patterns for several species as those derived in another study from Lake Ontario. Mainly Monoporeia and Pallasea, but partly also Mysis are potential vectors of trophic transport of PFASs in Lake Vättern, although further investigations should be conducted including additional replicates and species. Glacial relict crustaceans are sensitive to pollution in a system, and several fish species 3 in the present study had concentrations of L-PFOS above the AA-EQS value of 9.1 ng/g in fish, thus indicating PFAS contamination. Since many fish species feed on glacial relicts, contamination of these amphipods will transfer PFASs further in the Arctic char food web and could thus affect the whole eco-system in Lake Vättern. / Syftet med studien var att undersöka om glacialrelikta amfipoder utgör vektorer för transport av per- och polyfluorerade alkylsubstanser (PFAS)-ämnen i Vätternrödingens näringskedja. Sediment-, ytvatten- och biotaprover analyserades för PFAS-ämnen med ultra-prestanda vätskekromatografi med tandem-masspektrometri (UPLC-MS/MS) samt analys av stabila isotoper av δ 13C och δ15N för sediment- och biotaprover. Sedimentprover (n=3) föreslogs ha PFAS-kontaminering från olika ursprungskällor. Generellt låga halter detekterades i sediment (summan av alla detekterade PFAS-ämnen var 2.7 ng/g i St. Aspön, 2.9 ng/g i Visingsö och 0.6 ng/g i Omberg, rapporterat i torrvikt), jämfört med halterna i biota och flertalet ytvatten. Fördelningen av PFAS-ämnen i proverna från St. Aspön och Visingsö hade liknande homologmönster som skiljde sig från provet från Omberg. Detta styrktes sedan med data från isotopanalys. Medelkoncentrationen av alla detekterade PFAS-ämnen i potentiellt ej filmbildande brandskums (AFFF)-kontaminerade prover var 6 ng/L, medan den var 5 900 ng/L i potentiellt AFFF-kontaminerade prover. I ytvattenprover från Jönköpings flygplats och Kärnebäcken uppmättes halter av linjär perfluoroktansulfonat (L-PFOS) som alla överskred det europeiska gränsvärdet (AA-EQS) på 0,65 ng/L för PFOS i sötvatten (branddammen: 14 000 ng/L, diket: 600 ng/L, Sandserydsån: 160 ng/L, Kärnebäcken: 150 ng/L). Ett referensprov från sjön Unden (liknande ekosystem som Vättern) representerade diffusa utsläppskällor och hade liknande distribution av PFAS-ämnen som ett antal vattendrag i studien. Atmosfärisk deposition är en annan potentiell källa för PFAS-ämnen och då Vätterns ytvattenarea är stor (1900 km2) kan det vara en av de mest bidragande källorna. Detta bör undersökas närmre för att bättre bedöma den lokala miljöpåverkan. Trofiska magnifieringsfaktorer (TMFs) beräknades för L-PFOS, perfluorononansyra (PFNA) och perfluorotridekansyra (PFTrDA) till högre än 1, vilket indikerar biomagnifikation till högre trofiska nivåer. Av alla detekterade PFAS-ämnen i biota var L-PFOS mest förekommande (58 %), följt av PFTrDA (20 %), PFNA (6.7 %), perfluoroundekansyra (PFUnDA) (5.3 %), perfluorodekansyra (PFDA) (4.9 %) och perfluorooktansyra (PFOA) (2.9 %). Högst koncentrationer av alla analyserade ämnen detekterades i vitmärla (Monoporeia), den minsta av amfipoderna. Kontamineringsprofiler av karboxylater visade ett liknande mönster för ett flertal av arterna som även liknande de från en annan studie i sjön Ontario. Främst Vitmärla och taggmärla men delvis pungräka är potentiella vektorer för trofisk transport av PFAS-ämnen i Vättern, även om ytterligare studier med fler replikat och arter bör genomföras. Glacialrelikter är känsliga för förorening och flertalet fiskar analyserade i denna studie uppmätte koncentrationer av 5 L-PFOS över det europeiska gränsvärdet för PFOS i fisk (9,1 ng/g våtvikt), vilket indikerar att Vättern är förorenad. Då många fiskar äter glacialrelikta kräftdjur, skulle kontaminering av dessa amfipoder bidra till biomagnifikation i näringskedjan och således påverka hela Vätterns ekosystem.
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"Source characterization of soils contaminated with Polycyclic Aromatic Compounds (PACs) by use of Partial Least Squares Discriminant Analysis (PLS-DA)"Sinioja, Tim January 2017 (has links)
Polycyclic aromatic compounds (PACs) are organic compounds that include several sub-groups of toxic, persistent and carcinogenic environmental pollutants consisting of two or more non-substituted or substituted aromatic rings. Due to the complexity of PAC-mixtures found in the environment it can be challenging and time-consuming to track the sources of contamination. In the present study, multivariate data analysis (MVDA) models, such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to track sources of PACs at contaminated sites. Based on the chemical profile of 78 PACs obtained in GC-MS analysis of soils, 26 observations were classified according to their petrogenic, pyrogenic or urban background soil origin. Two soil samples of unknown origin collected at a contaminated site in Mjölby, Sweden, were successfully fitted to the validated PLS-DA model and their origins were determined as petrogenic. The study shows that validated PLS-DA models can be applied to predict the petrogenic, pyrogenic and urban background soil origins of samples collected at PAC contaminated sites, thus to track the sources of contamination. It is also concluded that 16 U.S. Environmental Protection Agency’s (EPA) priority polycyclic aromatic hydrocarbons (PAHs) are not sufficient to predict the origin of contamination with PCA or PLS-DA.
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How is substrate selectivity in hydride transfer decided in an alcohol dehydrogenase? : Directed evolution of alcohol dehydrogenase A from Rhodococcus ruber DSM 44541 through iterative saturation mutagenesis, a study to understand the structure and function relationship of enzymatic catalysisHillier, Heidi Therese January 2017 (has links)
No description available.
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Development of G-quadruplex stabilizing compounds identified through a High-Throughput ScreenBo Hanh, Thi Bo January 2017 (has links)
No description available.
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