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  • 851.
    Weissbach, Astrid
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bechemin, Christian
    French research Institute for the exploitation of the sea (Ifremer), L`Houmeau, France.
    Genauzeau, Sylvie
    French research Institute for the exploitation of the sea (Ifremer), L`Houmeau, France.
    Rudström, Maria
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Legrand, Catherine
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Alfred Wegener Institute for Polar and Marine Research, Germany.
    Impact of Alexandrium tamarense allelochemicals on DOM dynamics in an estuarine microbial community2012In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 13, p. 58-64Article in journal (Refereed)
    Abstract [en]

    Plankton and dissolved organic carbon (DOC) dynamics in fractionated estuarine microbial communities (<150 μm, <60 μm and <20 μm), incubated with allelopathic (lytic) or non allelopathic (non-lytic) Alexandrium tamarense filtrates were investigated over a period of 48 h. Additionally, the amount of dissolved organic matter (DOM) available for bacterial growth in the treatments was measured via bacterial seawater culture experiments immediately and 6 h after addition of A. tamarense filtrates. The lack of effect on DOC concentrations and plankton community composition in lytic treatments indicated that allelochemicals did not inhibit the growth of the microbial community. Nevertheless, bacterial seawater culture experiments provided evidence that lytic filtrate addition provoked the release of bioavailable DOM from the microbial community. Since DOM was only released from the largest seawater fraction, microorganisms >60 μm were probably most sensitive towards allelochemicals.

  • 852.
    Weissbach, Astrid
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Legrand, Catherine
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Effect of different salinities on growth and intra- and extracellular toxicity of four strains of the haptophyte Prymnesium parvum2012In: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 67, no 2, p. 139-149Article in journal (Refereed)
    Abstract [en]

    The present study investigates the effect of brackish (7 PSU) and marine (26 PSU) salinity on physiological parameters and intra- and extracellular toxicity in 4 strains of Prymnesium parvum Carter. The different P. parvum strains were grown in batch cultures in 2 trials under different experimental conditions to test the development of intra- and extracellular toxicity during growth. The response of P. parvum toxicity to salinity was validated using 2 protocols. Intra-specific variations in growth rate, maximal cell density (yield) and cell morphology were controlled by salinity. Extracellular toxicity was higher at 7 PSU in all strains, but no correlation was found between intra- and extracellular toxicity. The variation of extracellular toxicity in response to salinity was much greater than that of intracellular toxicity, which indicates that P. parvum may be producing a variety of substances contributing to its various types of 'toxicity'.

  • 853.
    Weissbach, Astrid
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Rudström, Maria
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olofsson, Martin
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bechemin, Christian
    IFREMER, France.
    Icely, John D
    Sagremarisco, Portugal.
    Newton, Alice
    Norwegian Institute for Air Research NIVA.
    Tillmann, Urban
    Alfred Wegener Institute for Polar and Marine Research, Germany.
    Legrand, Catherine
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Phytoplankton allelochemical interactions change microbial food web dynamics2011In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 56, no 3, p. 899-909Article in journal (Refereed)
    Abstract [en]

    This study investigates the effect of filtrates from an allelopathic dinoflagellate, Alexandrium tamarense, onfour microbial food webs that have been manipulated experimentally from natural seawater by modifying theavailability of resources in the form of dissolved organic carbon with additions of peptone, and by altering thegrazing pressure with size fractionation. Bacterial production was generally not affected by allelochemicals, butbacteria showed higher net growth in all food webs when allelochemicals were added, whereas heterotrophicnanoflagellates . 7 mm and ciliates were constrained in all food webs. Allelochemicals had the largest negativeeffects on microbial communities with low grazing pressure. In food webs with high grazing pressure andadditional resources, phytoplankton and small nanoflagellates were positively affected by the addition ofallelochemicals, suggesting that those were interfering with trophic interactions in the microbial communities. Bythe lysis of organisms sensitive towards allelochemicals, resources are made available and grazing pressure oncertain microorganisms is reduced. However, the intensity of these interactions is modulated by both theavailability of resources and the biomass of grazers in the initial food web.

  • 854.
    Weissbach, Astrid
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Tillmann, Urban
    Legrand, Catherine
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Allelopathic potential of the dinoflagellate Alexandrium tamarense on marine microbial communities2010In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 10, no 1, p. 9-18Article in journal (Refereed)
    Abstract [en]

    The impacts of two strains of the dinoflagellate Alexandrium tamarense, differing in lytic activity, on the abundance and the composition of microbial communities (<150 μm) were studied in North Sea water during spring with Phaeocystis globosa as a dominant species. Cell-free suspensions (supernatant) of exponentially growing lytic and non-lytic Alexandrium culture were added at different concentrations to natural microbial communities under nutrient rich conditions. The non-lytic strain had a positive impact on diatoms whereas the lytic strain suppressed phytoplankton growth in comparison to the control. P. globosa, present as single cells in the initial community, increased in abundance and formed colonies in all treatments. However, total abundance and number of colonies was low with lytic Alexandriumadditions, whereas shape of the colonies, but not abundance of cells, was affected by non-lytic Alexandrium additions. During the 4-day experiment, bacterial abundance was constantly higher with high lytic additions (highest concentration equivalent to 1000 cells ml−1) whereas nanoflagellate abundance in the same treatments was found to be lower at the end of the experiment. Initial bacterial community composition differed significantly among lytic Alexandrium, non-lyticAlexandrium and North Sea water. However, neither bacterial activity nor composition was significantly affected by the supernatants after 96 h. Our results indicated that Alexandrium allelochemicals do not inhibit growth and production of bacteria in seawater collected during spring in the North Sea.

  • 855.
    Welander, Ulrika
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Hejazi, Parisa
    Berenberg, Fredrik
    Isik, Güldem
    Rupar-Gadd, Katarina
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Strandmark, Gunnar
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Shojaosadati, Abbas
    Treatment of alpha-pinene contaminated air using biofilters with and without silicone oil2010In: Environmental Progress & Sustainable Energy, ISSN 1944-7442, E-ISSN 1944-7450, Vol. 29, no 3, p. 313-318Article in journal (Refereed)
    Abstract [en]

    Two biofilters equal in size were filled with perlite for treatment of -pinene-contaminated air. The perlite used for one of the biofilters was partially coated with silicone oil to make the surface of the particles more hydrophobic. The filters were run at 1.5, 2.5, and 5 L/min airflow rate (3.1, 1.9, and 0.9-min retention time). The filters were operated for 5.5 months. The results showed that the silicone oil-coated filter performed better at 2.5 L/min with a maximum elimination capacity of 20 g/(m3 h) in comparison with 15 g/(m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 L/min (40 g/m3 h), whereas it was slightly higher for the without oil filter at 5 L/min [35 g/(m3 h)]. The flow rate was set to 2.5 L/min once more (day 151). The results showed that the elimination capacity had increased to 35 g/(m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later run at 2.5 L/min is probably depending on that the number of microorganisms had increased during the experiment and that the oil-containing biofilter adsorbed -pinene to a higher extent than the biofilter without silicone oil during the start-up period. © 2009 American Institute of Chemical Engineers Environ Prog, 2010

  • 856.
    Wellving, Ingela
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pharmacological Treatment of Chronic Heart Failure: A Population based Study in a Heart Failure Clinic2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Heart failure is a disease that appears with systolic and/or diastolic dysfunction mainlyof the left ventricle. In systolic dysfunction, the decline in pumping capacity activates compensatorymechanisms largely through activation of the adrenergic and the renin-angiotensin-aldosteronesystems in order to increase the cardiac output. Chronic activation of these systems has long-termadverse consequences. Their actions are therefore blocked pharmacologically by ACE-inhibitors(ACEIs), angiotensin receptor blockers (ARBs), aldosterone receptor antagonists and beta-blockers.Aim of the study: To find out how a population of patients with chronic heart failure were treatedconcerning ACEIs/ARBs and beta-blockers, the tolerability of this treatment, if they were givendiuretics and the aldosterone antagonist spironolactone and if the treatment improved their condition.

    Material and methods: The study was performed on 84 patients with chronic heart failure visiting aHeart failure clinic from the first of July in 2000 until the end of June in 2001. The patients wereobserved during one year after the first visit or until they died.

    Results: ACEIs/ARBs were given to 80/84 patients (95.2%). Target doses were reached by 67/84patients (79.8%). One year after the visit, ACEI/ARB treatment was known to be present in 61/84(72.6%), absent in 12 and unknown in 11 patients. Increased levels of creatinin and/or potassium werethe most common reasons for decreasing the dose or interrupting the treatment (9 patients) and 6 patients had a change from an ACEI to an ARB because of cough. Beta-blockers were given to 71/84patients (84.5%). Target doses were reached by 20/84 patients (23.8%), less than the number ofpatients on target doses of ACEIs/ARBs (p<0.001). One year after the visit, beta-blockade treatmentwas known to be present in 57/84 (67.9%), absent in 13 and unknown in 14 patients. Breathlessness/exacerbation of heart failure was the most common reason for interrupting thetreatment or decreasing the dose (5 patients) followed by hypotension (4 patients). Diuretic treatment,except spironolactone, present in 67/84 patients at the time of the visit was stopped in 8 patients andspironolactone was known to be given to 31/84 patients. The heart failure condition one year after thevisit was considered to be better in 20 patients (23.8%), unchanged in 21 (25.0%), worse in 5 (6.0%),uncertain in 29 (34.5%) and 9 patients died. Hospital admissions decreased from 81.0% during theyear before the visit to 39.3% during the year after (p<0.001).

    Conclusion: More patients reached target doses of ACEIs/ARBs than of beta-blockers (p<0.001).Hospital admissions decreased from 81.0% before the visit to 39.3% after the visit (p<0.001).

  • 857.
    Wennersten, Lena
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Population-level consequences of variation2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Consequences of within population variation have recently attracted an increased interest in evolutionary ecology research. Theoretical models suggest important population-level consequences, but many of these predictions still remain to be tested. These issues are important for a deepened understanding of population performances and persistence, especially in a world characterized by rapid fragmentation of natural habitats and other environmental changes.

    I review theoretical models of consequences from intra population genetic and phenotypic variation. I find that more variable populations are predicted to be characterized by broader resource use, reduced intraspecific competition, reduced vulnerability to environmental changes, more stable population dynamics, higher invasive potential, enhanced colonization and establishment success, larger distribution ranges, higher evolvability, higher productivity, faster population growth rate, decreased extinction risk, and higher speciation rate, compared with less variable populations.

    To test some of these predictions I performed experiments and compared how different degree of colour polymorphism influences predation risk and establishment success in small groups. My comparisons of predation risk in mono- and polymorphic artificial prey populations showed that the risk of being eaten by birds does not only depend on the coloration of the individual prey item itself, but also on the coloration of the other members of the group. Two experiments on establishment success in small founder groups of

    Tetrix subulata pygmy grasshoppers with different degree of colour morph diversity show that establishment success increases with higher degree of diversity, both under controlled conditions in outdoor enclosures and in the wild. These findings may be important for re-stocking of declining populations or re-introductions of locally extinct populations in conservation biology projects.

    I report on remarkably rapid evolutionary shifts in colour morph frequencies in response to the changed environmental conditions in replicated natural populations of pygmy grasshoppers in fire ravaged areas. This finding

    1

    illustrates the high adaptive potential in a polymorphic species, and indicates the importance of preserved within-species diversity for evolutionary rescue.

    Finally, I review if theoretical predictions are supported by other published empirical tests and find strong support for the predictions that more variable groups benefit from reduced vulnerability to environmental changes, reduced population fluctuations and extinction risk, larger distribution ranges, and higher colonization or establishment success.

    In conclusion, my thesis illustrates how within-population variation influences ecological and evolutionary performances of populations both in the short and long term. As such, it emphasizes the need for conservation of biodiversity also within populations.

  • 858.
    Wennersten, Lena
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Forsman, Anders
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Population-level consequences of polymorphism, plasticity and randomized phenotype switching: a review of predictions2012In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 87, no 3, p. 756-767Article, review/survey (Refereed)
    Abstract [en]

    The consequences of among-individual phenotypic variation for the performance and ecological success of populations and species has attracted growing interest in recent years. Earlier reviews of this field typically address the consequences for population processes of one specific source of variation (plasticity or polymorphism), or consider one specific aspect of population performance, such as rate of speciation. Here we take a broader approach and study earlier reviews in order to summarize and compare predictions regarding several population-level consequences of phenotypic variation stemming from genetic polymorphism, developmental plasticity or randomized phenotype switching. Unravelling cause-dependent consequences of variation may increase our ability to understand the ecological dynamics of natural populations and communities, develop more informed management plans for protection of biodiversity, suggest possible routes to increased productivity and yield in natural and managed biological systems, and resolve inconsistencies in patterns and results seen in studies of different model systems. We find an overall agreement regarding the effects of higher levels of phenotypic variation generated by different sources, but also some differences between fine-grained and coarse-grained environments, modular and unitary organisms, mobile and sessile organisms, and between flexible and fixed traits. We propose ways to test the predictions and identify issues where current knowledge is limited and future lines of investigation promise to provide important novel insights.

  • 859.
    Wennersten, Lena
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Johansson, Jenny
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Karpestam, Einat
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Forsman, Anders
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Higher establishment success in more diverse groups of pygmy grasshoppers under seminatural conditions2012In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 93, no 12, p. 2519-2525Article in journal (Refereed)
    Abstract [en]

    Large founder groups and habitat match have been shown to increase the establishment success of reintroduced populations. Theory posits that the diversity of founder groups should also be important, but this has rarely been investigated. Here, experimental introductions of color-polymorphic Tetrix subulata pygmy grasshoppers into outdoor enclosures were used to test whether higher phenotypic diversity promotes establishment success. We show that the number of individuals present one year after introduction increases with color morph diversity in founder groups. Variance in establishment success did not decrease with increasing founder diversity, arguing against an important contribution of sampling effects or evolutionary rescue. Color morphs in T. subulata covary with a suite of other functionally important traits and utilize different resources. The higher establishment success in more diverse founder groups may therefore result, in part, from niche complementarity. Variation in establishment among groups was not associated with differences among source populations in reproductive capacities.

  • 860.
    Wennersten, Lena
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Karpestam, Einat
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Forsman, Anders
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Phenotype manipulation influences microhabitat choice in pygmy grasshoppers2012In: Current Zoology, ISSN 1674-5507, Vol. 58, no 3, p. 392-400Article in journal (Refereed)
    Abstract [en]

    The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specificphenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivocally demonstrated. Weconducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata onhabitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppersbelonging to either pale, intermediate or dark natural color morphs. However, after manipulating the grasshoppers’ phenotype, the utilizationthrough time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-paintedindividuals used warmer parts of the arena, at least during the initial stage of the experiment. We conclude that microhabitat choicerepresents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatialgenetic structure in the population because the phenotypes themselves may be genetically mediated

  • 861.
    Westerhult, David
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Weak Affinity Chromatography: Evaluation of Different Silica Supports for Protein Immobilizationand Effect of Mobile Phases Regarding Retentionand Non-specific Binding2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fragment based lead discovery (FBLD), where libraries of small fragments are screened andlater on developed to lead compounds, is an alternative to the classical drug discovery methods such as high trough-put screening. Weak affinity chromatography (WAC) is a new promising approach to the screening process of FBLD. WAC is performed by injections of fragments onto a high performance liquid chromatography (HPLC) column in which a protein is immobilized to a silica support. The retention of the injected fragments is correlated to the binding affinity of the fragments towards the immobilized protein. Immobilization capacity of three different silica materials with varying pore size (Kromasil240 Å, Nucleosil 1000 Å and Kromasil 300 Å) was evaluated by immobilization of trypsin. Retention of benzamidines on the trypsin columns was evaluated with different mobile phases. Contribution of non-specific binding in the interaction between the 4-aminobenzamidine and thrombin was estimated by frontal chromatography on a capillary columnusing PBS and PBS/acetonitrile as mobile phases. This study showed that the Kromasil 300 Å had a superior immobilization capacity of trypsin compared to the Kromasil 240 Å andthe Nucleosil 1000 Å (100 mg compared to 87.4 mg and 15.1 mg trypsin/g silica, respectively). However, the Nucleosil 1000 Å might be a more suitable support for the immobilization of larger proteins. Adding 5 % methanol or acetonitrile to the mobile phase resulted in a significant (p < 0.05) decreased retention of benzamidine fragments on the trypsin 240 Å column. Non-specific binding between thrombin and 4-ABA was not statistically significantly altered when 5 % acetonitrile was added to the mobile phase.

  • 862.
    Westgård, Emil
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Krisberedskap för naturolyckor hos miljöfarliga verksamheter2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Jönköpings län har under det senaste årtiondet drabbats av naturolyckor i form av extrema vädersituationer som orsakat flera allvarliga olyckor och nödsituationer. Länsstyrelsen i Jönköpings län vill därför öka förståelsen av hur tillståndspliktig miljöfarlig verksamhet har påverkats av de tidigare händelserna. Detta är en studie som omfattar riskhantering och beredskap för naturolyckor. Studien omfattar miljöfarlig verksamhet inom kategorierna A och B enligt förordningen (1998:899) om miljöfarlig verksamhet och hälsoskydd. Fokus ligger på att kartlägga och beskriva den övergripande situation av historiska händelser som inträffat. Resultatet ska kommuniceras till Länsstyrelsen i Jönköpings län som kan se över om det finns behov av kompetensutveckling inom detta område.

  • 863.
    Widjestam, Johan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Kombinationsbehandling med Ceplene/IL-2 av AML-patienter i första kompletta remission2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 864.
    Wigren, Johanna
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Kikaren-ögats förlängda arm: Uppföljning av Se Mer - effekten av tidig introduktion av optik för barn med nedsatt syn2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Utvärdera Se Mer-projektet som genomfördes vid Certec i Lund, från september 2003 till augusti 2005 och undersöka effekterna av tidig introduktion av optik för barn med nedsatt syn, samt om Se Mer-projektet hjälpt till att inspirera andra syncentraler att börja kikarträna små barn.

    Metod: En enkätundersökning med 12 deltagande Se Mer-barn och 13 deltagande föräldrar gjordes. De besvarade ett antal frågor om sitt deltagande i Se Mer-projektet och om hur deras situation ser ut idag. Enkätundersökningen publicerades med web-enkätprogrammet Google Doc. Vidare gjordes djupintervjuer med tre av barnen. Frågor skickades även ut via e-post till landets syncentraler. Totalt svarade 24 av 33 syncentraler på frågorna.

    Resultat: Enkätundersökningen visade att hälften av de 12 barnen som deltog i undersökningen använde samma kikare som de fick under Se Mer-projektet. Totalt använder 9 av 12 en kikare som synhjälpmedel idag, men flertalet anger att det är svårt att använda kikaren i skolan. På föräldrarnas enkät svarade 77% att de upplevt Se Mer-projektet mycket positivt. 38% svarade att Se Mer-projektet påverkat användningen av synhjälpmedel för deras barn. 21 av 24 syncentraler uppgav att Se Mer-projektet påverkat deras tillpassningen av en tidigare introduktion av optik för små barn med nedsatt syn.

    Slutsats: Effekten av tidig introduktion av optik för barn med nedsatt syn är positiv. Hälften av barnen använder fortfarande kikaren som provades ut i Se Mer-projektet och syncentralerna har inspirerats att startat träning tidigare. För att uppnå en optimal effekt av ett hjälpmedel måste man ta hänsyn till barnets mognad och utveckling.

  • 865.
    Wiklander, Jesper G.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Karlsson, Björn C. G.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Aastrup, Teodor
    Attana AB, Stockholm.
    Nicholls, Ian A.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    A synthetic polymer with avidin-like binding properties2010Conference paper (Refereed)
    Abstract [en]

    A series of streptavidin mimicking molecularly imprinted polymers has been developed and evaluated for their biotin binding characteristics. A combination of molecular dynamics and NMR spectroscopy was used to examine potential polymer systems, in particular with the functional monomers methacrylic acid and 2-acrylamidopyridine. Synthesis of co-polymers of ethylene dimethacrylate and one or both of these functional monomers was performed. A combination of radioligand binding studies and surface area analyses (BET, SEM) demonstrated the presence of selectivity in polymers prepared using methacrylic acid as functional monomer. This correlated well with the molecular dynamics studies, showing the power of this methodology as a prognostic tool for predicting the behaviour of molecularly imprinted polymers.

  • 866.
    Wiklander, Jesper G.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Karlsson, Björn C. G.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Aastrup, Teodor
    Nicholls, Ian A.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Towards a synthetic avidin mimic2011In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 400, no 5, p. 1397-1404Article in journal (Refereed)
    Abstract [en]

    A series of streptavidin-mimicking molecularly imprinted polymers has been developed and evaluated for their biotin binding characteristics. A combination of molecular dynamics and NMR spectroscopy was used to examine potential polymer systems, in particular with the functional monomers methacrylic acid and 2-acrylamidopyridine. The synthesis of copolymers of ethylene dimethacrylate and one or both of these functional monomers was performed. A combination of radioligand binding studies and surface area analyses demonstrated the presence of selectivity in polymers prepared using methacrylic acid as the functional monomer. This was predicted by the molecular dynamics studies showing the power of this methodology as a prognostic tool for predicting the behavior of molecularly imprinted polymers.

  • 867.
    Wikman, Susanne
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Edfors, Inger
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Johansson-Cederblad, Brita
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Linder, Cedric
    Uppsala universitet.
    University students’ reflections on the use of representations in introductory stereochemistry2011In: Science Learning & Citizenship, 2011Conference paper (Refereed)
  • 868.
    Wikström, Claes
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Kunskaper och föreställningar om övervikt och fetma: Enkätundersökning bland blivande sjuksköterskor och pedagoger på Högskolan i Borås2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Overweight and obesity is a growing problem in large parts of the world, including Sweden where approximately 10% of the adult population is considered obese. This leads to various health problems of physical, mental and social nature. Overweight and obesity often lead to contact with the health and care services where nurses have a role in supporting patients in changing their lifestyle in order to lose weight.

    This survey is a quantitative study in the form of a questionnaire directed at students in the nursing and the teacher educations at the University of Borås. The participants consisted of three groups: two nurse student groups - one with semester one students (VHB T1) and one with second year students, in semester three (VHB-T3) and one group of teacher students in their first semester (PED-T1). The primary purpose of the study was to investigate whether knowledge and conceptions of overweight and obesity differed between the nursing students and the teacher students. The seconsary purpose was to find out whether there were differences that could be related to which level the students were in their studies due to study elements related to lifestyle issues.

    The results of the survey show that the nursing students who had made the most progress in their education had the most measurable knowledge in overweight and obesity. These students (VHB T3) also regarded themselves as more knowledgeable and aware of lifestyle issues than semester one students, regardless of orientation (VHB-T1, PED-T1). The nursing students in semester three (VHB T3) felt better prepared for meeting patients with weight issues in their future profession than semester one students in the same education (VHB-T1).

  • 869.
    Wileryd, Sara
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Utvärdering av Lucentisbehandling vid ögonkliniken i Kalmar2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Syftet med arbetet var att utvärdera effekten av ett års behandling med Lucentis hos patienter med exsudativ åldersrelaterad makuladegeneration (AMD) på ögonkliniken i Kalmar.

    Metod: Ett brev skickades till de 41 patienter som någon gång under 2008 eller januari 2009 hade fått minst en behandling med Lucentis på ögonkliniken i Kalmar. I brevet tillfrågades patienterna om uppgifter fick hämtas ur deras journaler. Följande data inhämtades från de 33 patienter som godkände detta: kön, ålder, visus (avstånd och nära) före behandlingens början, visus (avstånd och nära) omkring ett år efter första behandlingen samt antal erhållna injektioner. Dessutom efterfrågades den subjektiva upplevelsen av visus via telefonsamtal med patienterna.

    Resultat: Den genomsnittliga synskärpan före behandlingens början och ett år senare var i princip oförändrad både på avstånd och nära håll. Denna utvärdering visar därmed inte någon signifikant förändring av visus efter ett års behandling med Lucentis. Det noterades dock hög standardavvikelse, vilket pekar på stora individuella skillnader mellan patienterna. 65,6% (avstånd) och 59,4% (nära) av patienterna upplever att synskärpan är förbättrad eller den samma efter behandlingen med Lucentis.

    Slutsats: Utvärderingen visar inte någon signifikant förändring av visus efter ett års behandling med Lucentis på ögonkliniken i Kalmar. Eftersom visus hos patienter med AMD sjunker utan behandling, tyder detta på att Lucentisbehandlingen på ögonkliniken i Kalmar har effekt och fördröjer synnedsättningen. Behandlingen på ögonkliniken i Kalmar är dock inte lika effektiv som den har varit i studier med månatliga injektioner eller månatliga återbesök med OCT och visuskontroll inför beslut om ytterligare Lucentisinjektion ska ges.

  • 870.
    Wilhelmsson, Victoria
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Ögats upplösningsförmåga i periferin är bättre med dynamiska stimuli än statiska stimuli2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 871.
    Wiman, Bo L. B.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Speaking integrity and uncertainty to power - is it doable in the climate change realm?2010In: Carbon and Climate Law Review, ISSN 1864-9904, E-ISSN 2190-8230, Vol. 4, no 2, p. 199-206Article in journal (Refereed)
  • 872.
    Wingren, Caroline
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Utvärdering av skillnad i metod att mäta överrefraktion samt hur överrefraktionen skiljer sig mellan tre olika instrument2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Syftet för denna studie var att se om det var någon skillnad i den överrefraktion man får fram hos patienten när överrefraktionen genomförs i provbåge, foropter och autorefraktor. Undersökningen gick även ut på att se om det blev någon skillnad om överrefraktionen genomfördes monokulärt med ocklusion eller binokulärt med dimlins.

    Metod: I studien deltog 30 personer i åldrarna 19 till 42 år. Det var sammanlagt 13 lågmyoper, 3 högmyoper, 5 hyperoper och 9 emmetroper som deltog i undersökningarna. Av dessa var 8 personer inte linsbärare och blev tillpassade med linser utifrån k-värden och HVID för att få en så bra sits som möjligt på linserna. De andra deltagarna blev tillsagda att komma till undersökningen med linser ordinerade till dem av en leg. optiker. Linsernas styrka kontrollerades sedan i provbåge, foropter och autorefraktor i slumpmässig ordning för att inte mätmetoden skulle påverka resultaten. Det var även slumpmässigt om överrefraktionen började med att utföras monokulärt eller binokulärt. Resultaten från överrefraktionerna antecknades och deltagarnas linsstyrkor antecknades för att sedan sammanställas i resultaten.

    Resultat: Resultaten visade att det fanns en signifikant skillnad mellan överrefraktionerna i provbågen och autorefraktorn samt foroptern och autorefraktorn då sfärisk ekvivalens användes för resultaten vid autorefraktorn. Däremot var skillnaden mellan provbågen och foroptern inte signifikant. Vid jämförelse binokulärt och monokulärt hittades endast en signifikant skillnad då foroptern användes som instrument.

    Slutsats: Av studien kunde det konkluderas att överrefraktion i provbåge eller foropter var lämpligast att använda. Det var inte heller någon signifikant skillnad i överrefraktion genomförd monokulärt och binokulärt.

  • 873. Witzgall, P
    et al.
    Trematerra, P
    Liblikas, Ilme
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bengtsson, M
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pheromone communication channels in tortricid moths: lower specificity of alcohol vs. acetate geometric isomer blends2010In: Bulletin of entomological research, ISSN 0007-4853, E-ISSN 1475-2670, Vol. 100, no 2, p. 225-230Article in journal (Refereed)
    Abstract [en]

    Discrimination of conspecific and heterospecific signals is a key element in the evolution of specific mate recognition systems. Lepidopteran pheromone signals are typically composed of several compounds that synergize attraction of conspecific and inhibit attraction of heterospecific males. Blends convey specificity, but not their single components, that are typically shared by several species. Many sex pheromones are blends of geometric or positional isomers of straight-chain acetates, while species-specific blends of analogous alcohols have not been described. We have, therefore, studied the attraction of tortricid moths to the geometric isomers (E,E)-, (E,Z)-, (Z,E)- and (Z,Z)-8,10-dodecadien-1-ol. Only one species responding to these alcohols seemed to be attracted to a blend of two isomers, while most species are attracted to only one alcohol isomer. Lack of a pronounced synergist or antagonist effect of the other geometric isomers explains the lack of specific attraction to isomer blends and reduces accordingly the number of specific communication signals composed of these alcohols. In comparison, many more species respond to the analogous (E,E)-, (E,Z)-, (Z,E)- and (Z,Z)-8,10-dodecadienyl acetates and their binary blends. The acetate isomers all play a behavioural role, either as attractants, attraction synergists or antagonists, and thus promote specific communication with acetate blends. Male moths seem to discriminate the acetate isomers with greater precision than the analogous alcohols. It is proposed that discrimination is facilitated by steric differences between the four acetate isomers, as compared to the more uniform steric properties of the alcohols.

  • 874.
    Wixe, Stina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Placebo effect on accommodative functions2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 875.
    Wogatai, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Förekomst av hyperopi bland hjälpsökande på en VFA-resa i Bolivia2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Att undersöka förekomst av hyperopi i förhållande till läskunnighet hos hjälpsökande hos VFA i Bolivia, samt jämföra med studier från andra delar av världen.

    Metod: Studien utfördes i april 2010 på tre olika orter i centrala Bolivia. Patienterna sökte själva upp platsen för att få en undersökning. Subjektiv refraktion utfördes binokulärt, utan dimning, med hjälp av provbåge, provlåda och syntavla med Snellen E, uppsatt på 5 meters avstånd. Hyperopi räknades som sfärisk ekvivalent ≥ +1,00 D, myopi som ≤ –0,25 DS.

    Resultat: 1 313 personer undersöktes, varav 1 271, mellan 6 och 92 år gamla, ingick i studien. Förekomsten av hyperopi var totalt 23,8% (som mest 39,8% hos kvinnor 66-92 år gamla, och som minst 10,7% hos kvinnor 6-19 år gamla), läskunnighet totalt var 81,7% (kvinnor 74,7%, män 90,7%). Det var något lägre läskunnighet bland hyperoper (78,1%) än bland myoper (83,2%) och emmetroper (82,7%).

    Slutsats: Bolivia verkar ha större förekomst av hyperopi än Asien och Europa. Hyperopi ökar med åldern, främst efter 50-årsåldern. Miljöfaktorn ser ut att ha viss betydelse.

  • 876.
    Wu, YQ
    et al.
    University of Pennsylvania, USA.
    Qu, H
    University of Pennsylvania, USA.
    Sfyroera, G
    University of Pennsylvania, USA.
    Tzekou, A
    University of Pennsylvania, USA.
    Kay, BK
    University of Illinois at Chicago, USA.
    Nilsson, Bo
    Uppsala University.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University Hospital.
    Ricklin, D
    University of Pennsylvania, USA.
    Lambris, JD
    University of Pennsylvania, USA.
    Protection of Nonself Surfaces from Complement Attack by Factor H-Binding Peptides: Implications for Therapeutic Medicine2011In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 186, no 7, p. 4269-4277Article in journal (Refereed)
    Abstract [en]

    Exposure of nonself surfaces such as those of biomaterials or transplanted cells and organs to host blood frequently triggers innate immune responses, thereby affecting both their functionality and tolerability. Activation of the alternative pathway of complement plays a decisive role in this unfavorable reaction. Whereas previous studies demonstrated that immobilization of physiological regulators of complement activation (RCA) can attenuate this foreign body-induced activation, simple and efficient approaches for coating artificial surfaces with intact RCA are still missing. The conjugation of small molecular entities that capture RCA with high affinity is an intriguing alternative, as this creates a surface with autoregulatory activity upon exposure to blood. We therefore screened two variable cysteine-constrained phage-displayed peptide libraries for factor H-binding peptides. We discovered three peptide classes that differed with respect to their main target binding areas. Peptides binding to the broad middle region of factor H (domains 5–18) were of particular interest, as they do not interfere with either regulatory or binding activities. One peptide in this group (5C6) was further characterized and showed high factor H-capturing activity while retaining its functional integrity. Most importantly, when 5C6 was coated to a model polystyrene surface and exposed to human lepirudin-anticoagulated plasma, the bound peptide captured factor H and substantially inhibited complement activation by the alternative pathway. Our study therefore provides a promising and novel approach to produce therapeutic materials with enhanced biocompatibility.

  • 877.
    Yu, Changxun
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Peng, Bo
    Peltola, Pasi
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Xiaoyan Tang, Tang
    Shurong, Xie
    Effect of weathering on abundance and release of potentially toxic elements in soils developed on Lower Cambrian black shales, P. R. China2012In: Environmental Geochemistry and Health, ISSN 0269-4042, E-ISSN 1573-2983, Vol. 34, no 3, p. 375-390Article in journal (Refereed)
    Abstract [en]

    This paper examines the geochemical features of 8 soil profiles developed on metalliferous black shales distributed in the central parts of the South China black shale horizon. The concentrations of 21 trace elements and 8 major elements were determined using ICP-MS and XRF, respectively, and weathering intensity (W) was calculated according to a new technique recently proposed in the literature. The data showed that the black shale soils inherited a heterogeneous geochemical character from their parent materials. A partial least square regression model and EFbedrock (enrichment factor normalized to underlying bedrock) indicated that W was not a major control in the redistribution of trace metals. Barium, Sn, Cu, V, and U tended to be leached in the upper soil horizons and trapped by Al and Fe oxides, whereas Sb, Cd, and Mo with negative EF values across the whole profiles may have been leached out during the first stage of pedogenesis (mainly weathering of black shale). Compared with the Chinese average soils, the soils were strongly enriched in the potentially toxic metals Mo, Cd, Sb, Sn, U, V, Cu, and Ba, among which the 5 first listed were enriched to the highest degrees. Elevated concentrations of these toxic metals can have a long-term negative effect on human health, in particular, the soils in mining areas dominated by strongly acidic conditions. As a whole, the black shale soils have much in common with acid sulfate soils. Therefore, black shale soils together with acid sulfate soils deserve more attention in the context of metal exposure and human health.

  • 878.
    Yu, Changxun
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Åström, Mats E.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Peltola, Pasi
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Drake, Henrik
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Oxidative weathering of black shale: A long-term humidity cell test2011In: Goldschmidt Conference Abstracts, Mineralogical Society , 2011, p. 2231-2231Conference paper (Refereed)
  • 879. Zammit, Carla M
    et al.
    Mangold, Stefanie
    Jonna, Venkateswara rao
    Mutch, Lesley A
    Watling, Helen R
    Dopson, Mark
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Department of Molecular Biology, Umeå University, Umeå, Sweden .
    Watkin, Elizabeth L J
    Bioleaching in brackish waters--effect of chloride ions on the acidophile population and proteomes of model species.2012In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 93, no 1, p. 319-329Article in journal (Refereed)
    Abstract [en]

    High concentrations of chloride ions inhibit the growth of acidophilic microorganisms used in biomining, a problem particularly relevant to Western Australian and Chilean biomining operations. Despite this, little is known about the mechanisms acidophiles adopt in order to tolerate high chloride ion concentrations. This study aimed to investigate the impact of increasing concentrations of chloride ions on the population dynamics of a mixed culture during pyrite bioleaching and apply proteomics to elucidate how two species from this mixed culture alter their proteomes under chloride stress. A mixture consisting of well-known biomining microorganisms and an enrichment culture obtained from an acidic saline drain were tested for their ability to bioleach pyrite in the presence of 0, 3.5, 7, and 20 g L(-1) NaCl. Microorganisms from the enrichment culture were found to out-compete the known biomining microorganisms, independent of the chloride ion concentration. The proteomes of the Gram-positive acidophile Acidimicrobium ferrooxidans and the Gram-negative acidophile Acidithiobacillus caldus grown in the presence or absence of chloride ions were investigated. Analysis of differential expression showed that acidophilic microorganisms adopted several changes in their proteomes in the presence of chloride ions, suggesting the following strategies to combat the NaCl stress: adaptation of the cell membrane, the accumulation of amino acids possibly as a form of osmoprotectant, and the expression of a YceI family protein involved in acid and osmotic-related stress.

  • 880. Zweifel, Ulla Li
    et al.
    Hagström, Åke
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Holmfeldt, Karin
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Thyrhaug, Runar
    Geels, Camilla
    Frohn, Lise Marie
    Skjoth, Carsten A.
    Karlson, Ulrich Gosewinkel
    High bacterial 16S rRNA gene diversity above the atmospheric boundary layer2012In: Aerobiologia, ISSN 0393-5965, E-ISSN 1573-3025, Vol. 28, no 4, p. 481-498Article in journal (Refereed)
    Abstract [en]

    The atmosphere is host to an omnipresent bacterial community that may influence fundamental atmospheric processes such as cloud formation and precipitation onset. Knowledge of this bacterial community is scarce, particularly in air masses relevant to cloud formation. Using a light aircraft, we sampled above the atmospheric boundary layer-that is, at heights at which cloud condensation occurs-over coastal areas of Sweden and Denmark in summer 2009. Enumeration indicated total bacterial numbers of 4 x 10(1) to 1.8 x 10(3) m(-3) air and colony-forming units of 0-6 bacteria m(-3) air. 16S rRNA gene libraries constructed from samples collected above the Baltic Sea coast revealed a highly diverse bacterial community dominated by species belonging to the genera Sphingomonas and Pseudomonas. Bacterial species known to carry ice-nucleating proteins were found in several samples. Modeled back trajectories suggested the potential sources of the sampled bacteria to be diverse geographic regions, including both marine and terrestrial environments in the northern hemisphere. Several samples contained 16S rRNA genes from plant chloroplasts, confirming a terrestrial contribution to these samples. Interestingly, the airborne bacterial community displayed an apparent seasonal succession that we tentatively ascribe to in situ succession in the atmosphere.

  • 881.
    Åman, Sandra
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Stabila bakfyllningar2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fyllning i kakor (s.k. bakfyllning) kan under bakning och särskilt under lagring ge negativa effekter så som migrering av fyllning och olja ut i kakdegen. Valet av fettsystem i fyllningen och dess smältpunkt är av stor betydelse för att erhålla önskvärd konsistens och textur. Syftet med examensarbetet var att minimera dessa negativa effekter samt att kartlägga faktorer som påverkar detta. Tidigare bakförsök vid AarhusKarlshamn har visat att fyllningens partikelstorlek påverkar migreringen, då migreringen tycks öka med ökande partikelstorlek. Examensarbetet innefattade provbakningar, fysikaliska analyser och sensoriska test. Baktemperatur och avsvalningshastigheten varierades. Kakdegens socker varierades med strö- och florsocker för att ge olika porositet. Fyllningarna baserades på tre olika fettsystem; A, B och B:C. Fettsystem B gav dock fyllningen för lös konsistens och uteslöts senare ur studien. Fyllningarnas normala (N) partikelstorlek var 50 μm och fyllning baserad på A valsades för att reducera partikelstorleken till 10, 20 respektive 40 μm, vilka namngavs A(10), A(20) respektive A(40). Oljemigrering studerades efter 3 dagar och 2,5 veckor genom sensorisk utvärdering och texturanalys. Differential scanning calorimetry och reologi användes för att studera fyllningens fysikaliska egenskaper. Ingen signifikant skillnad i textur kunde påvisas med olika socker i kakdegen eller med de olika använda baktemperaturerna (160 resp. 190 °C). Den sensoriska och visuella utvärderingen visade att för kakor med fyllning A(N) och A(40) gav mest oljemigrering. Detta styrktes med resultat från texturanalysen. Smältpunkten för fyllning baserad på A bestämdes till ~48,4 °C och fyllning baserad på B:C till 60,6 °C. Partikelstorlek visades således ha inverkan på oljemigreringen och en partikelstorlek ≤ 20 μm är nödvändig för att fyllningen ska vara stabil, dvs. ingen migrering av fyllning och olja.

  • 882.
    Åström, Mats E.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Nystrand, Miriam
    Gustafsson, Jon-Petter
    Österholm, Peter
    Nordmyr, Linda
    Reynolds, Jason
    Peltola, Pasi
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Lanthanoid behaviour in an acidic landscape2010In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 74, no 3, p. 829-845Article in journal (Refereed)
    Abstract [en]

    Lanthanoids were studied in a boreal landscape where an abundance of acid sulfate soils and Histosols provide a unique opportunity to increase the understanding of flow these metals behave in acidic soils and waters and interact with soil and aqueous organic matter. In the acid sulfate soils lanthanoids are mobile as reflected in high to very high concentrations in soil water and runoff (typically a few mg 1(-1) but Lip to 12 mg 1(-1)) and abundant release by several relatively weak extractants (ammonium acetate EDTA, sodium pyrophosphate, hydroxylamine hydrochloride) applied on bulk soil. Normalisation with the lanthanoid pool in the underlying parent materials (sulphide-bearing sediments deposited in brackish-water) and soil water showed that the extensive release/retention in the acidic soil was accompanied by large, and variable, fractionation trends across the lanthanoid series. In low-order streams draining these soils, the lanthanoid concentrations were high and, as indicated by frontal ultrafiltration and geochemical modelling, largely dissolved (<1 kDa) in the form of the species LnSO(4)(+) and Ln(3+). In other moderately acidic stream waters (pH 4.3-4.6), organic complexation was predicted to be important in the <1 kDa fraction (especially for the heavy lanthanoids) and strongly dominating in the colloidal phase (1 kDa-0.45 mu m). Along the main stem of a stream in focus (catchment area of 223 km(2)), lanthanoid concentrations increased downstream, in particular during high flows, caused by a downstream increase in the proportion of acid sulfate soils which are extensively flushed during wet periods. The geochemical models applied to the colloidal Ln-organic phase were not successful in predicting the measured fractionation patterns.

  • 883.
    Åström, Mats E.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Österholm, Peter
    Gustafsson, Jon Petter
    Nystrand, Miriam
    Peltola, Pasi
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Nordmyr, Linda
    Boman, Anton
    Attenuation of rare earth elements in a boreal estuary2012In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 96, p. 105-119Article in journal (Refereed)
    Abstract [en]

    This study focuses on attenuation of rare earth elements (REE) when a boreal creek, acidified and loaded with REE and other metals as a result of wetland drainage, empties into a brackish-water estuary (salinity < 6 parts per thousand). Surface water was collected in a transect from the creek mouth to the outer estuary, and settling (particulate) material in sediment traps moored at selected locations in the estuary. Ultrafiltration, high-resolution ICP-MS and modeling were applied on the waters, and a variety of chemical reagents were used to extract metals from the settling material. Aluminium, Fe and REE transported by the acidic creek were extensively removed in the inner/central estuary where the acidic water was neutralised, whereas Mn was relatively persistent in solution and thus redistributed to particles and deposited further down the estuary. The REE removal was caused by several contemporary mechanisms: co-precipitation with oxyhydroxides (mainly Al but also Fe), complexation with flocculating humic substances and sorption to suspended particles. Down estuary the dissolved REE pool, remaining after removal, was fractionated: the < 1 kDa pool became depleted in the middle REE and the colloidal (0.45 mu m-1 kDa) pool depleted in the middle and heavy REE. This fractionation was controlled by the removal process, such that those REE with highest affinity for the settling particles became most depleted in the remaining dissolved pool. Modeling, based on Visual MINTEQ version 3.0 and the Stockholm Humic Model after revision and updating, predicted that the dissolved (< 0.45 mu m) REE pool in the estuary is bound almost entirely to humic substances. Acid sulphate soils, the source of the REE and other metals in the creek water, are widespread on coastal plains worldwide and therefore the REE attenuation patterns and mechanisms identified in the studied estuary are relevant for recognition of similar geochemical processes and conditions in a variety of coastal locations. (C) 2012 Elsevier Ltd. All rights reserved.

  • 884.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Data needs for socio-economic analysis - bridging the gap between safety and impact assessments2012In: Contemporary Concepts in Toxicology, Society for Toxicology , 2012Conference paper (Other academic)
  • 885.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Importance of health and environmental impact assessments for the evaluation of restriction proposals and authorisation applications under REACH2012In: Presentation vid European Environment & Public Health Consultative Conference (3d EPH Annual Meeting) i Krakow, 25-27 oktober, 2012., 2012Conference paper (Other academic)
  • 886.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Modeling vapor pressure.2011In: Presentation vid ECO Summer School, Leiden University, 26 september, 2011., 2011Conference paper (Other academic)
  • 887.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Non-testing methods in the safety assessment of chemicals.: Naturvetenskapligt seminarium, Kalmar, 25 november, 2011.2011Other (Other academic)
  • 888.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Read-across and QSARs in the risk assessment of food and feed2010In: Presentation vid Experts Workshop on "Dealing with Uncertainty of Non-Test Methods under REACH" i Helsingfors, 23-24 september, 2010., 2010Conference paper (Other academic)
  • 889.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    The role of EFSA in integrated food-environment risk assessments2010In: Presentation vid ILSI Europe 2010 Annual Symposium i Bryssel, 25-26 mars, 2010., 2010Conference paper (Other academic)
  • 890.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Treatment of uncertainty from QSAR models in risk assessment2009In: Presentation vid the Annual Meeting of the Society for Risk Analysis, Baltimore, Maryland, 6-9 december 2009., 2009Conference paper (Other academic)
  • 891.
    Öberg, Tomas
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Iqbal, Muhammad Sarfraz
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    The chemical and environmental property space of REACH chemicals2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 87, no 8, p. 975-981Article in journal (Refereed)
    Abstract [en]

    The European regulation on chemicals, REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals), came into force on 1 June 2007. With pre-registration complete in 2008, data for these substances may provide an overview of the expected chemical space and its characteristics. In this paper, using various in silico computation tools, we evaluate 48782 neutral organic compounds from the list to identify hazardous and safe compounds. Two different classification schemes (modified Verhaar and ECOSAR) identified between 17% and 25% of the compounds as expressing only baseline toxicity (narcosis). A smaller portion could be identified as reactive (19%) or specifically acting (2.7%), while the majority were non-assigned (61%). Overall environmental persistence, bioaccumulation and long-range transport potential were evaluated using structure-activity relationships and a multimedia fugacity-based model. A surprisingly high proportion of compounds (20%), mainly aromatic and halogenated, had a very high estimated persistence (> 195 d). The proportion of compounds with a very high estimated bioconcentration or bioaccumulation factor (> 5000) was substantially less (6.9%). Finally, a list was compiled of those compounds within the applicability domain of the models used, meeting both persistence and bioaccumulation criteria, and with a long-range transport potential comparable to PCB. This list of 68 potential persistent organic pollutants contained many well-known compounds (all halogenated), but notably also five fluorinated compounds that were not included in the EINECS inventory. This study demonstrates the usability of in silico tools for identification of potentially environmentally hazardous chemicals.

  • 892.
    Öberg, Tomas
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Iqbal, Muhammad Sarfraz
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    The REACH space of organic chemistry and hazard properties.2011In: Presentation vid 6th International Symposium on Computational Methods in Toxicology and Pharmacology Integrating Internet Resources (CMTPI-2011) i Maribor, 3-7 september, 2011., 2011Conference paper (Other academic)
  • 893.
    Öberg, Tomas
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Liu, Tao
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Extension of a prediction model to estimate vapor pressures of perfluorinated compounds (PFCs)2011In: Chemometrics and Intelligent Laboratory Systems, ISSN 0169-7439, E-ISSN 1873-3239, Vol. 107, no 1, p. 59-64Article in journal (Refereed)
    Abstract [en]

    Perfluorinated compounds (PFCs) are persistent and have been found globally as environmental contaminants. Release into the environment can occur from manufacturing, industrial and consumer uses. The vapor pressure is an important physical property influencing both the release and the environmental partitioning, but few reliable experimental determinations are available. Here we update a previous PLS regression model to cover also this compound class, using only a few calibration compounds. The recalibration is accomplished by applying a leverage-based weighting scheme that is generally applicable in updating structure–property relationships. The predictive performance is validated with an external validation set and is considerably better than for other standard estimation software, both with regard to accuracy and precision. The model can be given a chemical interpretation and the prediction error for the liquid vapor pressure is within 0.2 log units of Pa. Finally, the model is applied and vapor pressure estimates are reported for more than 200 PFCs where no reliable experimental data are available.

  • 894.
    Öberg, Tomas
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Liu, Tao
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Updating existing QSAR models: selection and weighting of new data2010In: Journal of Cheminformatics, ISSN 1758-2946, E-ISSN 1758-2946, Vol. 2, no Suppl 1, p. P19-Article in journal (Other academic)
    Abstract [en]

    Computational chemistry and quantitative structure-activity relationships (QSAR) are foreseen to be extensively used in the implementation of the new REACH regulation for chemicals in Europe. However, for some compound groups the data are too few in number to permit both calibration and testing of a new model. Usage and previously developed or updated models are then viable alternatives.Perfluorocarboxylic acids (PFCAs) and fluoroteleomer alcohols (FTOHs) are two groups of environmentally relevant compounds, with unique physical and chemical properties. The subcooled liquid vapour pressure (pL) is one such property, where experimental determinations are limited and far from consistent [1]. Updating is, however, challenging when the new compounds are far outside of the original calibration domain space. But by carefully selecting and weighting only three new compounds, we have been able to update a previously developed general QSAR model [2], to cover the new domain while maintaining predictive performance for the earlier calibration and test data. The optimal weighting scheme was determined from the sample leverages and residuals in the calibration phase [3].The performance of this re-calibrated model greatly surpassed previous modelling attempts [4], when applied to an external test set of two PFCAs and four FTOHs with pL in the range 0.2-200 Pa; with Q2Ext = 0.994 and RMSEP = 0.190 units of log Pa. The domain coverage also increased from 1% to 51%, for 426 perfluoroalkylated compounds selected from the REACH registration list, the PhysProp database, and the OECD 2006 survey [5]. Selection and weighting of new calibration data can thus facilitate the extension and use of existing QSAR models. This investigation was supported by the EU FP7 project CADASTER (grant agreement no. 212668).

  • 895.
    Öhlund, Sten-Erik
    et al.
    Linnaeus University, Faculty of Health, Social Work and Behavioural Sciences, School of Health and Caring Sciences. Linköping University, Sweden ; Logica Sverige AB, Sweden.
    Åstrand, Bengt
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Petersson, Göran
    Linnaeus University, Faculty of Health, Social Work and Behavioural Sciences, School of Health and Caring Sciences.
    Improving interoperability in ePrescribing2012In: Interactive Journal of Medical Research, E-ISSN 1929-073X, Vol. 1, no 2, article id e17Article in journal (Refereed)
    Abstract [en]

    Background: The increased application of eServices in health care, in general, and ePrescribing (electronic prescribing) in particular, have brought quality and interoperability to the forefront. The application of standards has been put forward as one important factor in improving interoperability. However, less focus has been placed on other factors, such as stakeholders’ involvement and the measurement of interoperability. An information system (IS) can be regarded to comprise an instrument for technology-mediated work communication. In this study, interoperability refers to the interoperation in the ePrescribing process, involving people, systems, procedures and organizations. We have focused on the quality of the ePrescription message as one component of the interoperation in the ePrescribing process.

    Objective: The objective was to analyze how combined efforts in improving interoperability with the introduction of the new national ePrescription format (NEF) have impacted interoperability in the ePrescribing process in Sweden, with the focus on the quality of the ePrescription message.

    Methods: Consecutive sampling of electronic prescriptions in Sweden before and after the introduction of NEF was undertaken in April 2008 (pre-NEF) and April 2009 (post-NEF). Interoperability problems were identified and classified based on message format specifications and prescription rules.

    Results: The introduction of NEF improved the interoperability of ePrescriptions substantially. In the pre-NEF sample, a total of 98.6% of the prescriptions had errors. In the post-NEF sample, only 0.9% of the prescriptions had errors. The mean number of errors was fewer for the erroneous prescriptions: 4.8 in pre-NEF compared to 1.0 in post-NEF.

    Conclusions: We conclude that a systematic comprehensive work on interoperability, covering technical, semantical, professional, judicial and process aspects, involving the stakeholders, resulted in an improved interoperability of ePrescriptions.

  • 896.
    Öhrling, Christina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Förhållandet mellan fixationsdisparitet och prematura2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Syftet med arbetet har varit att undersöka fixationsdisparitet hos personer som fötts för tidigt och för att se om det finns någon skillnad mellan dessa och personer som fötts i fullgången tid. Syftet har även varit att undersöka om Saladin card kan anses vara en pålitlig metod för att mäta fixationsdisparitet.

    Metod: Fixationsdispariteten mättes upp med Saladin card och associerade forier mättes upp med Mallett unit. Vidare mättes dissocierade forier upp med Modifierad Thorington och stereoseendet mättes upp med Titmus fly. I resultaten jämfördes 22 st prematura deltagare med 22 st fullgångna deltagare. Samtliga 44 personer jämfördes sedan mot varandra vid en utvärdering av de olika mätmetoderna.

    Resultat: Vid en jämförelse mellan de båda grupperna, prematura och fullgångna, fanns ingen signifikant skillnad i resultaten. Medelvärdet för de båda grupperna låg inom vad som räknas som normala värden för de olika mätningarna. En jämförelse mellan Saladin card och Mallet unit påvisade likartade resultat.

    Slutsats: Det var ingen signifikant skillnad i fixationsdisparitet mellan de fullgångna och de prematura deltagarna. Saladin card är ett mer känsligt test än Mallett unit för att mäta upp små horisontella och vertikala avvikelser. 

  • 897.
    Österman, Marie
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Utvärdering av kapillärt protrombinkomplex i EDTA-microtainerrör2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Blodcirkulationen är essentiell för människans överlevnad. När blodets koagulation- och antikoagulationssystem kommer i obalans kan koagelbildning orsaka venös tromboembolism, blodpropp. Patienter som har haft en blodpropp behandlas med antivitamin K-läkemedel (Waran®) för att förebygga recidiv. Dosen är individanpassad och för att erhålla rätt terapeutisk verkan krävs övervakning genom mätning av protrombinkomplex i plasma.

    Syftet med studien var att utföra en utvärdering samt göra en hållbarhetsstudie på en ny provtagningsrutin för kapillära protrombinkomplex.I studien ingick 48 personer varav 33 män och 15 kvinnor. Åldersfördelning var 22-88 år och medianålder var 62 år. I samband med ordinarie provtagning, vilken användes som referensmetod, för P-protrombinkomplex togs ca 350 μL blod kapillärt i EDTA-microtainerrör. Genom spädning (1:4) av EDTA-blod i citratbuffert möjliggjordes analys av kapillärt P-protrombinkomplex efter 1, 8 och 24 timmar. Samtliga prover analyserades med turbidimetrisk detektion i instrumentet ACL Top 500. Studiens analysresultat jämfördes mot referensmetoden.Studien visar att protrombinkomplexaktiviteten är stabil i blod med EDTA-tillsats i upp till 8 timmar efter provtagning. Dock kan stabiliteten inte garanteras hos individer med hereditära koagulationsrubbningar.

  • 898.
    Österström, Ola
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Lilja, Clas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Carbonic anhydrase and calcium mobilization from the avian eggshell during embryonic development2010In: 25th International Ornithological Congress 22 to 28 August 2010 ISBN 978-85-911618-0-5 Campos do Jordão, SP, BRAZIL: Abstracts of the 25 International Ornithological Congress, 2010, p. 683-Conference paper (Refereed)
    Abstract [en]

    The avian eggshell contributes to successful embryogenesis by acting as the major source of calcium. It has been suggested, moreover, that birds have evolved eggshells with different structures adapted to cope with different calcium requirements imposed by different growth rates and modes of development. Yet the mechanism of calcium removal from the avian eggshell by the embryo remains unknown. Using enzyme histochemistry, we here test an old hypothesis stating that calcium is released from the eggshell by means of acidification by the action of carbonic anhydrase (CA) in the extra-embryonic chorio-allantoic membrane (CAM). This enzyme catalyses the reversible reaction CO2+H2O <-> H+HCO3 and is known to take significant part in acid-base regulation in the body. We examined CAMs from two bird species, Coturnix japonica and Sturnus vulgaris, with very different growth rates and modes of development. The CAMs were examined for CA activity at the later stages of embryonic development. However, in all CAMs examined, staining for CA was absent, leading us to the conclusion that existing hypothesis about a link between CA and embryonic calcium mobilization from the avian eggshell is at present premature.

  • 899.
    Österström, Ola
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Lilja, Clas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Evolution of avian eggshell structure.2012In: Journal of morphology (1931. Print), ISSN 0362-2525, E-ISSN 1097-4687, Vol. 273, no 3, p. 241-247Article in journal (Refereed)
    Abstract [en]

    Data are presented suggesting that birds have evolved eggs with shells containing different structures (numbers of mammillae per unit of inner eggshell surface area, i.e., mammillary densities) to cope up with different calcium requirements imposed by different growth rates and modes of development. Precocial bird species grow slowly, but have high mammillary density, while altricial bird species grow rapidly, but have low mammillary density. These results suggest an adaptation associated with growth rate and mode of development and show, moreover, that the mammillary layer is indicative of the breeding biology of the bird.

15161718 851 - 899 of 899
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