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  • 251.
    Karlsson, Lovisa
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Natural weathering of shale products from Kvarntorp2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    A severe shortage of many, to mankind, valuable elements are to be expected in the near future. Therefor is it of utmost importance to find these deposits and a way to refine the elements with as little negative effect on the environment as possible.

    One deposit of valuable elements such as U, V, Mo and Sr are the so called alum shale. Alum shale is a variety of sulfidic black shale which is rich in pyrite, FeS2, and organic carbon. Primary due to its contents of hydrocarbons and uranium the alum shale has been mined at different sites throughout Sweden. One of these sites was Kvarntorp in the region of Närke. The shale which had have its contents of hydrocarbons extracted through dry distillation was dumped into a heap that is now known as Kvarntorpshögen.

    The remaining hydrocarbons that this processed material still contain are to this day (2011) warm, with temperatures up to some hundred degrees Celsius. Due to this heat, infiltration of rainwater is held at a minimum. What no one knows however; is for how long Kvarntorpshögen will remain warm. Once it cools; many toxic elements will leak into the surrounding environment due to natural weathering caused by precipitation and frost wedging. The study also included a heating treatment of 70°C which is a temperature that the material of Kvarntorpshögen may be capable of generating by itself. This is assumed to be a good temperature for weathering processes; because it increases the kinetics of chemical reactions but also allows the presence of water.

    The results of this study shows that summer will be the season that contributes the most to the leaching of elements, of which some are toxic. Newly exposed surfaces of various shale materials often contain elements that is easily leached by water. Once this coat is washed away however, further leaching of that element decreases. Exceptions from this pattern in some shale products were shown by for example vanadium and molybdenum.

    The digestion data show that the completely processed shale, which makes up the majority of Kvarntorpshögen, still have a high content of rare and valuable elements. Making Kvarntorpshögen itself interesting for extraction processes in the future.

  • 252.
    Karlsson, Magnus
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Strid, Åke
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sirsjö, Allan
    Örebro universitet, Hälsoakademin.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Homology Models and Molecular Modeling of Human Retinoic Acid Metabolizing Enzymes Cytochrome P450 26A1 (CYP26A1) and P450 26B1 (CYP26B1)2008Inngår i: Journal of Chemical Theory and Computation, ISSN 1549-9618, E-ISSN 1549-9626, Vol. 4, nr 6, s. 1021-1027Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Homology models of cytochrome P450 26A1 and cytochrome P450 26B1 were constructed using the crystal structures of human, CYP2C8, CYP2C9, and CYP3A4 as templates for the model building. The homology models generated were investigated for their docking capacities against the natural substrate all-trans-retinoic acid (atRA), five different tetralone-derived retinoic acid metabolizing blocking agents (RAMBAs), and R115866. Interaction energies (IE) and linear interaction energies (LIE) were calculated for all inhibitors in both homology models after molecular dynamics (MD) simulation of the enzyme-ligand complexes. The results revealed that the homologues had the capacity to distinguish between strong and weak inhibitors. Important residues in the active site were identified from the CYP26A1/B1-atRA complexes. Residues involved in hydrophobic interactions with atRA were Pro113, Phe222, Phe299, Val370,

    Pro371, and Phe374 in CYP26A1 and Leu88, Pro118, Phe222, Phe295, Ile368, and Tyr272 in CYP26B1. Hydrogen bonding interactions were observed between the atRA carboxylate group and Arg 90 in CYP26A1 and with Arg76, Arg95, and Ser369 in CYP26B1.

  • 253.
    Karlsson, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Jass, Jana
    Örebro universitet, Akademin för naturvetenskap och teknik.
    CXCL8 regulation of urothelial cells by lactobacilli2011Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Background

    CXLC8 is an important cytokine that attracts immune cells such as neutrophils and macrophages during infections. This cytokine is released from many cell types including epithelial cells such as the urothelial cells found in the urinary tract. CXCL8 release is dramatically increased when urothelial cells meet bacteria such as uropathogenic Escherichia coli, which are the main cause of urinary tract infections. CXCL8 is needed during the course of the infection; nevertheless, high levels have been associated with chronic inflammation and cancer, and are in those cases considered detrimental to health. Lactobacillus is a diverse group of lactic acid bacteria and a major component of our microbiota. Many are also commercially available as probiotics, and even if they have shown effectiveness as preventative supplements for both infections and supporting bowel regularity, much is left to learn about their mode of action. We know that many probiotics are immunomodulators and affect immune cell function, especially in immune cells. However, less is known about their effect on epithelial cell immune function and the possible variation immunomodulation between different Lactobacillus species.   

     

    Results

    To test the CXCL8 modulating abilities of Lactobacillus, numerous species were used for screening urothelial cell CXCL8 release. We wanted to assess the role of lactobacilli on resting cells, but also how they affect CXCL8 in cells that are already stimulated with E. coli similar to the case of a urinary tract infection. We found that most lactobacilli had a marginal effect on cytokine release in resting cells not challenged with E. coli. However, E. coli-challenged cells subsequently exposed to lactobacilli showed a significant increase or decrease of CXCL8 levels. Many of the tested species changed cytokine levels severalfold in both directions. Comparing the effects between species using evolutionary trees based on 16S rRNA did not reveal any grouping of effects based on the genetic similarity between the different taxa.

     

    Conclusion

    Many lactobacilli have the ability to alter the levels of secreted CXCL8, especially in E. coli-challenged cells. Interestingly, we could not group the effect on CXCL8 based on their evolutionary relationship suggesting that the effects on CXCL8 is analogous in its nature and have evolved independently in many of the tested species. However, as for probiotic activity which is often strain specific, CXCL8 modulating features are also likely to be associated with individual strains. Although we cannot explain the big differences between bacteria, both up- and downregulation of CXCL8 is interesting from a therapeutical perspective. Many pathogens, including uropathogenic E. coli actively inhibit signals that lead to cytokine release and immune migration, and it can in those cases be beneficial to increase CXCL8, whereas decreased cytokine levels might be advantageous in other conditions such as chronic inflammation.  

  • 254.
    Karlsson, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lam, Simon
    Department of Microbiology and Immunology, University of Western Ontario, and The Lawson Health Research Institute, St Josephs Hospital, London Canada.
    Reid, Gregor
    Department of Microbiology and Immunology, University of Western Ontario, and The Lawson Health Research Institute, St Josephs Hospital, London Canada.
    Jass, Jana
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lactobacillus rhamnosus GR-1 augments NF-κB and TNF in Escherichia coli-challenged human epithelium2008Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Epithelial cells are often first responders to microbial invasion, resulting in release of inflammatory mediators such as cytokines and chemokines and subsequent recruitment of immune cells. Several strains from the genus Lactobacillus have been attributed probiotic properties and some of them have been shown to be able to modulate the immune response in vitro and in vivo. L. rhamnosus GR-1, a known probiotic strain was allowed to co-culture with an uroepithelial cell line challenged with heat-killed pathogenic E. coli, resulting in a synergistic up-regulation of the transcription factor NF-κB and increased release of the pro-inflammatory cytokine TNF. Although this L. rhamnosus strain was a poor inducer of uroepithelial NF-κB alone compared to heat-killed E. coli, together with this pathogenic stimulus, it efficiently elicited an epithelial immune response. This effect was greatly reduced if using non-viable lactobacilli suggesting secretion of the active substance. Secreted proteins were isolated and partially mimicked the effect found with viable lactobacilli. Potentiation of the host immune response towards pathogenic E. coli at an early stage using lactobacilli products could facilitate the removal of undesired microbes by activation of the NFκB transcription factor and consequently, epithelial immunity.

  • 255.
    Karlsson, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lam, Simon
    Department of Microbiology and Immunology, University of Western Ontario and The Lawson Health Research Institute, London ON, Canada.
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Jass, Jana
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Released substances from lactobacilli influence immune responses in human epithelial cells2010Inngår i: Abstracts of the 3rd Swedish-Hellenic Life Sciences Research Conference, Athens, March 25-27, 2010 / [ed] Fragiskos Kolisis, Nikolaos Venizelos, 2010, s. 367-368Konferansepaper (Fagfellevurdert)
  • 256.
    Karlsson, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Concentration dynamics and speciation of uranium in a boreal forest creek: six years of weekly observations2011Inngår i: The new uranium mining boom: challenges and lessons learned / [ed] Broder Merkel, Mandy Schipek, Springer Berlin/Heidelberg, 2011, s. 119-126Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The concentrations of major components as well as uranium and some transition metals (Cu, Zn, Cd, Pb) and DOC were measured in a small creek within a boreal catchment during a six years time period. Variations up to four orders were found during the entire period. There was an evident correlation between uranium concentration with concentrations of Fe and Al, however not with DOC (in the absence of carbonate, average pH of 5.5). It is evident that environmental quality monitoring in small catchments must include the highly variable conditions leading to large variations in concentrations and speciation.

  • 257.
    Karlsson, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bäckström, Mattias
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Weathering mechanisms and composition of effluents from a sulphide mine waste deposit after covering: twenty years of field data2010Inngår i: Mine water and innovative thinking: proceedings 2010 / [ed] Christian Wolkersdorfer, Antje Freund, Nova Scotia, Canada: Cape Breton, University Press , 2010, s. 359-362Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In 1988 a deposit with some 500,000 m³ of coarse sulphidic mine waste at Bersbo, Sweden, was covered with compacted illitic clay or cement stabilised coal fly-ash (CeFill) to prevent  eathering and the transport of metals. Theoretically, oxidation of pyrite would give a sulphate/iron ratio in solution exceeding 2, if oxygen is the electron acceptor, but below 2 if Fe(III) is the oxidizing agent. The effluents had ratios of 35—50 and 2—0.8 before and after covering, respectively, why it is concluded that weathering continued. The altered hydrological regime contributes to changes in metal concentrations in the surrounding surface water.

  • 258.
    Karlsson, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Grahn, Evastina
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Mobility of Cs and Pu from fallout in boreal lake sediments2009Konferansepaper (Fagfellevurdert)
  • 259.
    Karlsson, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sjöberg, Viktor
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Concentration dynamics in a boreal catchment: trace elements, REEs and humic substances2011Inngår i: 25th International Applied Geochemistry Symposium, 22-26 August, 2011, Rovaniemi, Finland / [ed] Pertti Sarala, V. Juhani Ojala, Marja-Leena Porsanger, Rovaniemi, Finland: Vuorimiesyhdistys - Finnish Association of Mining and Metallurgical Engineers , 2011, s. 63-63Konferansepaper (Fagfellevurdert)
  • 260.
    Karlsson, Stefan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sjöberg, Viktor
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Grandin, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Heterotrophic leaching of LD-slag: formation of organic ligands2011Inngår i: Mine Water: Managing the Challenges: proceedings of the International Mine Water Association Congress 2011 / [ed] Trude R.Rüde, Antje Freund, Christian Wolkersdorfer, Aachen: RWTH , 2011, s. 371-374Konferansepaper (Fagfellevurdert)
  • 261.
    Karlsson, Tobias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Linnér, Jakob
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Avfyrnings-/relälåda2009Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    This is a report of our examination project in electronics carried out for Bofors Test Center in Karlskoga. The task was to construct an electronic devise for starting up different kinds of measuring systems in exact time during test sequences. The modules that are used today are old and unreliable. Our goal was to construct a prototype, which later on is supposed to be developed into a useful system.

  • 262.
    Khalaf, Hazem
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Characterization and environmental influences on inflammatory and physiological responses2010Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Pharmaceuticals are regularly released into the environment, in particular nonsteroidalanti-inflammatory drugs (NSAIDs) and antibiotics. The measuredconcentrations are relatively low and have therefore been considered to be harmless.However, several pharmaceuticals, including naproxen and atenolol, are stable for upto 1 year in the environment, which increases the risk for accumulation. Evaluation ofthe effects of pharmaceuticals on induced inflammatory responses is thereforenecessary for the assessment of potential risks. Since NF-κB and MAPK are the mainpathways known to be critical regulators of inflammatory responses, intracellularsignalling and effects on these systems were examined in vitro using human cell-lines.NSAIDs were shown to significantly reduce NF-κB activity at environmentallyrelevant concentrations. Suppression of immune responses may lead to progressiveinfections since inflammatory responses are controlled by a cooperative activity ofAP-1 and NF-κB. Alterations in the activity of transcription factors and proinflammatorycytokine and chemokine levels such as TNF, IL-6 and CXCL8 areassociated with several human diseases including cystic fibrosis and AIDS. PMAexposure resulted in a rapid NF-κB activation, while extended treatment suppressedNF-κB and activated AP-1. Suppression of NF-κB activity may be due to PKCdependentBcl10 degradation, which decreased in response to PMA and correlatedwith the NF-κB activity. Regulation of cytokine expression revealed that NF-κB wasessential for IL-6 but not CXCL8 expression following specific inhibition of NF-κB,without affecting AP-1 activity. Furthermore, several reports have indicated theimportance of a functional NF-κB complex in zebrafish embryogenesis, whereblockage of NF-κB activation resulted in a deformation of the tail. Our results indicatea suppression of apoptotic pathways following activation of inflammatory mediatorsin response to HK E. coli treatment. These signals acted to direct zebrafish sexdifferentiation towards feminization. NF-κB was shown to regulate zp2 geneexpression, an indicator of oocyte development. Zebrafish sex determination was alsoshown to start early, prior to 16 days post fertilization. The results support thetransition through a juvenile ovary stage and suggests that steriodogenesis is aconsequence of sex differentiation rather than a regulatory mechanism.Control of prescription, use and disposal of pharmaceuticals is therefore importantto preserve human health, biotic processes and to avoid developmental alterations inaquatic organisms. The complexity of regulatory systems involved in inflammationsuggest that there is a need to further evaluate the signalling pathways involved inorder to provide a better understanding of cellular responses to manmade substances,but also to offer an insight into possible development of alternative treatments forhuman diseases with elevated cytokine/chemokine levels.

  • 263.
    Khalaf, Hazem
    et al.
    Örebro universitet, Hälsoakademin.
    Jass, Jana
    Örebro universitet, Akademin för naturvetenskap och teknik. Lawson Hlth Res Inst, Univ Western Ontario, London ON, Canada; Dept Microbiol & Immunol, Univ Western Ontario, London ON, Canada.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Differential cytokine regulation by NF-κB and AP-1 in Jurkat T-cells2010Inngår i: BMC Immunology, ISSN 1471-2172, E-ISSN 1471-2172, Vol. 11, artikkel-id 26Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Activator protein (AP)-1 and nuclear factor (NF)-κB largely control T-cell activation, following binding offoreign antigens to the T-cell receptor leading to cytokine secretion. Elevated levels of pro-inflammatory cytokines andchemokines such as TNF, IL-6 and CXCL8 are associated with several human diseases including cystic fibrosis, pulmonary fibrosis and AIDS. The aim of this study was to investigate the role of the transcription factors, AP-1 and NF-κB, in IL-6 and CXCL8 regulation in Jurkat T-cells.

    Results: Phorbol myristate acetate (PMA) exposure resulted in an up-regulation of AP-1 and down-regulation of NF-κBactivity, however, exposure to heat killed (HK) Escherichia. coli MG1655 resulted in a dose-dependent increase in NF-κBactivity without affecting AP-1. The cytokine profile revealed an up-regulation of the chemokine CXCL8 and the pro-inflammatory cytokines TNF, IL-2 and IL-6 following treatment with both PMA and HK E. coli, while the levels of the anti-inflammatory cytokine IL-10 were not affected by PMA but were significantly down-regulated by HK E. coli. AP-1activation was significantly increased 2 h after PMA exposure and continued to increase thereafter. In contrast, NF-κBresponded to PMA exposure by a rapid up-regulation followed by a subsequent down-regulation. Increased intracellular Ca2+ concentrations countered the down-regulation of NF-κB by PMA, while similar treatment with calcium ionophore resulted in a reduced NF-κB activity following induction with HK E. coli. In order to further study NF-κB activation, we considered two up-stream signalling proteins, PKC and Bcl10. Phosphorylated-PKC levels increased inresponse to PMA and HK E. coli, while Bcl10 levels significantly decreased following PMA treatment. Using an NF-κBactivation inhibitor, we observed complete inhibition of IL-6 expression while CXCL8 levels only decreased by 40% atthe highest concentration. Treatment of Jurkat T-cells with PMA in the presence of JNK-inhibitor suppressed both CXCL8 and IL-6 while PKC-inhibitor primarily decreased CXCL8 expression.

    Conclusion: The present study shows that NF-κB regulated IL-6 but not CXCL8. This complex regulation of CXCL8suggests that there is a need to further evaluate the signalling pathways in order to develop new treatment fordiseases with elevated CXCL8 levels, such as AIDS and autoimmune diseases.

  • 264.
    Khalaf, Hazem
    et al.
    Örebro universitet, Hälsoakademin.
    Jass, Jana
    Örebro universitet, Hälsoakademin.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Influence of growth conditions on in vitro regulation of NF-κB activity in Jurkat T-cells2010Manuskript (preprint) (Annet vitenskapelig)
  • 265.
    Khalaf, Hazem
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Larsson, Anders
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Berg, Håkan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    McCrindle, Robert
    Wellington Laboratories Inc., Research Division, Guelph, Ontario, Canada.
    Arsenault, Gilles
    Wellington Laboratories Inc., Research Division, Guelph, Ontario, Canada.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Diastereomers of the Brominated Flame Retardant 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane Induce Androgen Receptor Activation in the HepG2 Hepatocellular Carcinoma Cell Line and the LNCaP Prostate Cancer Cell Line2009Inngår i: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 117, nr 12, s. 1853-1859Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Reported incidences of prostate cancer and masculinization of animals indicate a release of compounds with androgenic properties into the environment. Large numbers of environmental pollutants have been screened to identify such compounds; however, not until recently was 1,2-dibromo-4-(1,2-dibromoethyl)cyclohex​ane (TBECH) identified as the first potent activator of the human androgen receptor (hAR). TBECH has been found in beluga whales and bird eggs and has also been found to be maternally transferred in zebrafish.

    Objectives: In the present study we investigated interaction energies between TBECH diastereomers (α, β, γ, and δ) and the hAR, and their ability to activate the receptor and induce prostate-specific antigen (PSA) expression in vitro.

    Methods: We performed computational modeling to determine interaction energies between the ligand and the AR ligand-binding site, and measured in vitro competitive binding assays for AR by polarization fluorometry analysis. We used enzyme-linked immunosorbent assays to determine PSA activity in LNCaP and HepG2 cells.

    Results: We found the γ and δ diastereomers to be more potent activators of hAR than the α and β diastereomers, which was confirmed in receptor binding studies. All TBECH diastereomers induced PSA expression in LNCaP cells even though the AR present in these cells is mutated (T877A). Modeling studies of LNCaP AR revealed that TBECH diastereomers bound to the receptor with a closer distance to the key amino acids in the ligand-binding domain, indicating stronger binding to the mutated receptor.

    Conclusions: The present study demonstrates the ability of TBECH to activate the hAR, indicating that it is a potential endocrine disruptor.

  • 266.
    Khalaf, Hazem
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ochsner, Scott A.
    Koskinen, Jarno
    Karlsson, Marie
    Karlsson, Jesper
    Sreenivasan, Rajini
    McKenna, Neil J.
    Orban, Laszlo
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Zebrafish feminization in response to heat killed bacterial exposure suggests a function for anti-apoptotic genes in oocyte maintenanceManuskript (preprint) (Annet vitenskapelig)
  • 267.
    Khalaf, Hazem
    et al.
    Örebro universitet, Hälsoakademin.
    Salste, Lotta
    Karlsson, Patrik
    Ivarsson, Per
    Jass, Jana
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    In vitro analysis of inflammatory responses following environmental exposure to pharmaceuticals and inland waters2009Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 407, nr 4, s. 1452-1460Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pharmaceuticals are regularly released into the environment; in particular non-steroidalanti-inflammatory drugs (NSAIDs) and antibiotics. Erythromycin, naproxen, furosemideand atenolol are reported to be stable for up to 1 year in the environment, which increasesthe risk for accumulation. In the present study we have measured the occurrence andconcentration of pharmaceuticals in river Viskan (Jössabron) downstream of a sewagetreatment plant in Borås, Sweden. Pharmaceuticals and water samples were tested forpotential human risk by evaluating inflammatory responses (NF-κB and AP-1) using humanT24 bladder epithelial cells and Jurkat T-cells. NF-κB activity in T24 cells was significantlyreduced by all NSAIDs analysed (diclofenac, ketoprofen, naproxen, ibuprophen anddextropropoxyphene), but also by trimethoprim, using environmentally relevantconcentrations. NF-κB and AP-1 activation was further analysed in response to watersamples collected from different locations in Sweden. Dose-dependent down-regulation ofAP-1 activity in Jurkat cells was observed at all locations. At two locations (Jössabron andAlmenäs) down-regulation of NF-κB was observed. In contrast, the NF-κB response waspotentiated by exposure to water from both locations following activation of NF-κB bytreatment with heat-killed Escherichia coli. To determine the involvement ofpharmaceuticals in the responses, T24 cells were exposed to the pharmaceutical mixture,based on the determined levels at Jössabron. This resulted in reduction of the NF-κBresponse following exposure to the pharmaceutical mixture alone while no potentiationwas observed when cells were co-exposed to heat killed E. coli and pharmaceuticals. Theobtained results demonstrate that the identified pharmaceuticals affect the inflammatoryresponses and furthermore indicate the presence of unknown substance(s) with the abilityto potentiate inflammatory responses

  • 268.
    KHALIQ, ALI ABDUL
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Gas Dispersal Simulation in ROS2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This work presents a 3-D gas dispersal simulation and olfactory detection system

    implemented in ROS. Gas dispersal simulation integrates OpenFOAMflow

    simulation and a filament-based gas propagation model to simulate gas dispersion

    for compressible flows with a realistic turbulence model. The olfactory

    detection system models the response of metal oxide gas sensor to the simulated

    gas.

    Olfaction related experiments in mobile robots can be highly complex and

    hazardous due to the involvement of flammable and toxic gases. Moreover, the

    results of mobile olfaction task depends on the characteristics of environment

    and on the characteristics of odor detection system. The precision of results of

    this task is usually effected due to the variability of interrelationships between

    these characteristics which can create complications to focus on task aspect.

    The motivation behind the development of this simulation package is to make

    environment and odor detection system controllable, where experiments can

    be repeated under identical conditions, bypassing the environmental hazards

    so that the research work can concentrate on task aspect.

    The simulation package is validated through the results obtained by various

    tests including constant concentrations in ideal conditions as well as changing

    concentration in turbulent environment.

    i

  • 269.
    Kjellander, Johan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Inventering av datorspel och verktyg för att utveckla datorspel lämpliga för användning i undervisning av lkärarstudenter2011Rapport (Annet vitenskapelig)
    Abstract [sv]

    Rapporten beskriver ett inventeringsarbete utfört med syfte att studera hur spel- och simuleringsteknik kan användas i lärarutbildning. En bred sökning har gjorts, huvudsakligen via Internet. Ett antal spel har studerats och några av dem redovisas i rapporten. Mängden professionsspel är mycket stor och likaså mängden spel för skolelever, särskilt inom de naturvetenskapliga ämnena.

    Antalet spel för lärarutbildning är däremot begränsat och de som identifierats är snarare forskningsprojekt än kommersiella produkter. Endast fem spel avsedda för lärarutbildning har identifierats och dessa har studerats noggrannare. I den mån det har varit möjligt har demoversioner eller skarpa versioner av spelen provkörts och utvecklarna kontaktas med frågor om vilken teknik som använts för att utveckla spelen.

    De fem undersökta spelen för lärarutbildning har alla utvecklats med mycket enkel teknik, PHP, Flash, XHTML och liknande. Det är dock relativt enkelt att hitta andra professionsspel som utvecklats med  avancerad teknik som animerad 3D, multi-player osv. Det råder således brist på bra initiativ till utveckling av spel för lärarutbildning. Sverige intar en framskjuten position i världen när det gäller utveckling av spel för underhållning av olika slag. Det borde inte vara omöjligt att också placera sig bland de främsta när det gäller utveckling av professionsspel.

  • 270.
    Kjellander, Johan A. P.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rahayem, Mohamed
    Örebro universitet, Akademin för naturvetenskap och teknik.
    An integrated platform for 3D measurement with geometric reverse engineering2009Inngår i: Computer-Aided Design and Applications, ISSN 1686-4360, Vol. 6, nr 6, s. 877-887Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Geometric Reverse Engineering (GRE) can be described as the process of fitting surfaces to point data and connecting them to topologically well defined CAD models. We have mounted a laser profile scanner on an industrial robot with a turntable and interfaced them to an Open Source CAD platform. With this tool we have developed an integrated system that can automatically plan and control the robot movements needed to measure an object of unknown shape. Details of this work have been published earlier but we have not described the platform used to integrate the hardware with the GRE software. This paper illustrates the multi disciplinary nature of that problem and investigates what the requirements are for a suitable CAD tool.

  • 271.
    Kjellander, Johan A. P.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rahayem, Mohamed
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Planar segmentation of data from a laser profile scanner mounted on an industrial robot2009Inngår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 45, nr 1-2, s. 181-190Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In industrial applications like rapid prototyping, robot vision, and geometric reverse engineering, where speed and automatic operation are important, an industrial robot and a laser profile scanner can be used as a 3D measurement system. This paper is concerned with the problem of segmenting the data from such a system into regions that can be fitted with planar surfaces. We have developed a new algorithm for planar segmentation based on laser scan profiles and robot poses. Compared to a traditional algorithm that operates on a point cloud, the new algorithm is shown to be more effective and faster.

  • 272.
    Kjellander, Manne
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Akustisk design av studiorum för musikinspelning2010Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta projekt genomfördes i samarbete med akustikern Erling Nilsson på företaget Ecophon i Hyllinge. Uppdragsgivare var musikproducenten Magnus Ågren som äger studion Flow Music i Malmö. Uppgiften var att förbättra akustiken i ett av Flow Musics studiorum. Rummet hade före projektet en hård och obehaglig akustik. För att komma fram till ett åtgärdsförslag specificerades först hur enskilda akustiska egenskaper skulle påverkas för att ge ett så bra resultat som möjligt. Utvärderande undersökningar visade sedan att samtliga parametrar påverkats i rätt riktning, om än inte alla så mycket som beräknat. Åtgärderna gick i huvudsak ut på att tillföra absorption i mellanregister och diskant samt att diffusera ljudfältet så mycket som möjligt. De utvärderande mätningarna visar att lite mer absorption och diffusion i de låga frekvenserna kan behövas.

  • 273.
    Klasson, Martin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Revision of Lacquer Range2010Independent thesis Advanced level (degree of Master (One Year)), 15 poäng / 22,5 hpOppgave
    Abstract [sv]

    Detta examensarbete utfördes på lack- och tryckavdelningen på företaget

    Emballator Ulricehamns Bleck med målet att undersöka om det fanns brister och

    slöserier i det befintliga lacksortimentet.

    Efter en noggrann nulägesanalys som inkluderade bland annat genomgång av

    applicerbara datablad, arbetsplatsintroduktion och studiebesök hos en av

    företagets lackleverantörer genomfördes arbetet utan missöden. Nulägesanalysen

    resulterade i en översikt av dagens lacksortiment och efter det fortsatte arbetet

    med att ta fram en egenskapsmatris innehållande samtliga lacker i sortimentet.

    Efter att de lacker som föll inom författarens specifikation för dubbletter

    identifierats togs ett antal rekommendationer för hur företaget bör agera för att ha

    ett uppdaterat sortiment fram. Förutom detta har författaren tagit fram ett förslag

    på hur företaget skall testa sina insideslacker för att i framtiden ha möjligheten att

    undersöka om några av dessa kan tas ut ur sortimentet.

  • 274.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A validation methodology for agent-based simulations2008Inngår i: SAC '08: Proceedings of the 2008 ACM symposium on applied computing (SAC) / [ed] Roger L. Wainwright, Hisham M. Haddad, New York, NY: ACM Press , 2008, s. 39-43Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Validity forms the basic prerequisite for every simulation model, therefore also for reasonable usage of the agent-based simulation paradigm. However, models based on the multi-agent system metaphor tend to need some particular approaches. In this paper, I propose a process for validating agent-based simulation models that combines face validation, sensitivity analysis, calibration and statistical validation.

  • 275.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Agent-Based Simulation EngineeringManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The history of agent-based models started in the 1970ies with singular yet path-breaking examples such as the Segregation model by T. Schelling [Schelling, 1971]. From end of the 80ies on more and more agent-based models were developed and implemented. However, almost no simulation engineering happened. Due to the relation to social sciences, mostly sociologists and psychologists used the paradigm of simulated humans based on rather complex models of human decision making to model hypotheses and theories about societal dynamics. The resulting models were complex but abstract. The role of empirical embeddedness is still discussed in the area of social simulation. Practioneers from more engineering-oriented domains like traffic simulation or researchers from domains with long simulation background like theoretical biology or engineering found the techniques associated with agent-based simulation interesting, yet not mature enoughto actually apply them.

    Agent-based simulation definitely is a highly valuable tool, especially when studying complex self-organizing systems in many domains. Thus, the question arises, what shows the maturity of a simulation paradigm and how the achievement of a high level of applicability can be brought forward? The answer is basically that engineering-like development and some form of good practice have to be established. In particular, this leads to the following issues that have to be addressed for fostering the development of agent-based models.

    • Deep understanding of the “object”, that means understanding of agent-based models themselvesand what particular feature is useful in what particular context.
    • Development of best practice: Establishing knowledge about how to build an agent-basedmodel efficiently and in a way that costs can be a priori estimated.

    Until now, none of these items is solved in a satisfying way. However, they are necessarily achieved at least partially for improving the broad applicability of agent-based modeling and simulation. Steps leading to the general aim of this book – fostering the applicability of agent-based simulation – can be derived from these considerations.

    A basic prerequisite and therefore first step is collecting specific knowledge about agent-based simulation and the context of its appropriate application. This refers to properties of simulation questions and modeling targets as well as to theoretical and empirical requirements for model design, implementation and usage.

    The second step concerns the development of an agent-based simulation. Although the general process model for developing simulation models, presented in every simulation textbook, can also be applied for agent-based simulation, the problem goes deeper than just using an appropriate specification or implementation language. Agent-based simulations are generative. It is not jus tdescribing what was observed, but finding agent behavior and interactions that produce a particular phenomenon. This idea has several consequences ranging from missing micro-macro links over non-linear models and tendencies to full detail to several levels of validation. Thus, developing methods for bridging the gap between macro-level objectives and appropriate micro-level programs in a systematic and reproducible way is the challenge for agent-based simulation engineering.

    A third step must consider practical application of the theoretical foundations. Basically,learning how to model for simulation possesses the same characteristics as learning how to program software. One might read about language constructs, but how its actually working is only experience-able by doing it. Therefore, a detailed presentation of simulation models and theirconstruction has to be part of a book about simulation engineering.

    Thus, this book sums up experiences in methodological research and application of agent-based simulation, especially in modeling complex and self-organizing systems. This book is a further step towards systematic engineering of agent-based models involving appropriate meta-models, procedures for development, conceptual and technical design and validation of models. It bridges the gap between established techniques related to modeling and simulation and the approaches and requirements for complex agent-based simulation modeling.

  • 276.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Measuring complexity of agent-based simulation: an attempt using metrics2008Inngår i: Languages, methodologies and development tools for multi-agent systems: Revised selected and invited papers / [ed] Mehdi Dastani, Amal El Fallah Seghrouchni, João Leite, Paolo Torroni, Berlin: Springer , 2008, s. 123-138Konferansepaper (Fagfellevurdert)
  • 277.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Multi-Agenten-Systeme2013Inngår i: Handbuch der Künstlichen Intelligenz / [ed] Günther Görz, Josef Schneeberger and Ute Schmid, Oldenbourg Wissenschaftsverlag GmbH, 2013, 5., s. 999-1007Kapittel i bok, del av antologi (Fagfellevurdert)
  • 278.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    SeSAm: visual programming and participatory simulation for agent-based models2009Inngår i: Multi-agent systems: simulation and applications / [ed] Adelinde Uhrmacher, Danny Weyns, Boca Raton, Fla: CRC Press, 2009, s. 477-508Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 279.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bernon, Carole
    Paul Sabatier University, Toulouse, France.
    Self-Adaptive Agents for Debugging Multi-Agent Simulations2011Inngår i: Proc. of the 3rd ADAPTIVE 2011: The Third International Conference on Adaptive and Self-Adaptive Systems and Applications / [ed] J. Fox and A. Rausch, Xpert Publishing Services, 2011, s. 79-84Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this contribution, we propose an adaptation-drivenmethodology for the technical design and implementation of multi-agent simulations that is inspired by the concept of "living design". The simulated agents are capable of evaluatingtheir behavior and self-adapt for improving the overall model.For this aim, the modeler describes critical, non valid situations in the life of an agent, or the complete agent system, and explicitly specifies repair knowledge for these situations.

  • 280.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hatko, Reinhard
    University of Würzburg.
    Butz, Martin V.
    University of Würzburg.
    Agent learning instead of behavior implementation for simulations: a case study using classifier systems2008Inngår i: Multiagent System Technologies / [ed] Ralph Bergmann, Gabriela Lindemann, Stefan Kirn, Michal Pechoucek, Berlin: Springer , 2008, s. 111-122Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Although multi-agent simulations are an intuitive way of conceptualizing systems that consist of autonomous actors, a major problem is the actual design of the agent behavior. In this contribution, we examine the potential of using agent-based learning for implementing the agent behavior. We enhanced SeSAm, a platform for agent-based simulation, by replacing the usual rule-based agent architecture by XCS, a well-known learning classifier system (LCS). The resulting model is tested using a simple evacuation scenario. The results show that on the one hand side plausible agent behavior could be learned. On the other hand side, though, the results are quite brittle concerning the frame of environmental feedback, perception and action modeling.

  • 281.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Klubertanz, Georg
    Rindsfüser, Guido
    Agent-based pedestrian simulation of train evacuation integrating environmental data2009Inngår i: KI 2009: advances in artificial intelligence / [ed] Bärbel Mertsching, Marcus Hund, Zaheer Aziz, Berlin: Springer, 2009, s. 631-638Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Simulating evacuation processes forms an established way of layout evaluation or testing routing strategies or sign location. A variety of simulation projects using different microscopic modeling and simulation paradigms has been performed. In this contribution, we are presenting a particular simulation project that evaluates different emergency system layout for a planned train tunnel. The particular interesting aspect of this project is the integration of realistic dynamic environmental data about temperature and smoke propagation and its effect on the agents equipped with high-level abilities.

  • 282.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ossowski, SaschaUniversity Rey Juan Carlos, Madrid, Spain.
    Multiagent system technologies: 9th German Conference, MATES 2011, Berlin, Germany, October 6-7, 2011. Proceedings2011Konferanseproceedings (Fagfellevurdert)
    Abstract [en]

    This book constitutes the proceedings of the 9th German Conference on Multiagent System Technologies held in Berlin, Germany, in October 2011. The 12 revised full papers presented together with 6 short parers were carefully reviewed and selected from 50 submissions. Providing an interdisciplinary forum for researchers, users, and developers to present and discuss latest advances in research work as well as prototyped or fielded systems of intelligent agents and multi-agent systems, the papers cover the whole range of this sector and promote its theory and applications.

  • 283.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rindsfüser, Guido
    Emch&Berger AG, Bern, Switzerland.
    Agent-based route (and mode) choice simulation in real-world networks2011Inngår i: 2011 IEEE/WIC/ACM International Conference on  Web Intelligence and Intelligent Agent Technology (WI-IAT) / [ed] Jomi F. Hübner, Jean-Marc Petit, Einoshin Suzuki, IEEE, 2011, s. 22-29Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Mode and route choice are central elements of traffic simulations. Traditionally they form two subsequent steps in the four-step process where first, the simulated population distributes among available transportation modes and then their movement is assigned to the roads respectively other networks. However, these two phases are better dealt with simultaneously as choices are highly depending on each other. In this paper, we are suggesting an agent-based combined route and mode choice model that is not only able to resemble traditional simulations, but provides the means for new applications. As the simulated agents are active and situated while moving through the network, they are able to react to unforeseen events such as the closing of a link. Thus we can reproduce the self-organized re-distribution of travelers to new routes depending on when/where they are notified about the problem. We illustrate the feasibility and usefulness of our agent-based mode and route choice simulation using a real-world network of a small-size Swiss town.

  • 284.
    Klügl, Franziska
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Vizzari, GiuseppeUniversity of Milano-Bicocca, Milano, Italy.Vokrinek, JiriCzech Technical University, Prague, Czech Republic.
    Proceedings of the 8th International Workshop on Agents in Traffic and Transportation: Workshop at AAMAS 2014, Paris, May, 5/6th 20142014Konferanseproceedings (Fagfellevurdert)
  • 285.
    Koshmak, Gregory
    Örebro universitet, Akademin för naturvetenskap och teknik.
    An android based monitoring and alarm system forpatients with chronic obtrusive disease.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    An android based monitoring and alarm system for

    patients with chronic obtrusive disease.

  • 286.
    Koskinen, Jarno
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Johnny
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sox9a regulation of ff1a in zebrafish (Danio rerio) suggests an involvement of ff1a in cartilage development2009Inngår i: Comparative Biochemistry and Physiology A, ISSN 1095-6433, E-ISSN 1531-4332, Vol. 153, nr 1, s. 39-43Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The NR5A family of orphan nuclear receptors has been implicated in development of the vertebrate embryo, but their exact role remains largely unknown. To evaluate the regulation and developmental role for ff1a (NR5A2) in zebrafish (Danio rerio), we performed morpholino knockdown to block translation of the ff1a gene and the upstream located sox9a gene during embryogenesis. Using a newly developed antibody against Ff1a we could show that the ff1a morpholinos were functional and that a reduction in the expression of Ff1a correlated to altered phenotypes. The role of Sox9a in ff1a gene regulation and function was studied using sox9a morpholinos. Knock-down of sox9a resulted in abolished ff1a signals in the somites, mandibular arches and pharyngeal arches, while the pectoral fin signal remained. The reduction in Ff1a levels correlated to truncated tails and cranio-facial malformation. As Sox9a is involved in chondrocyte development we analysed for cartilage formation and found that blocking translation of either sox9a or ff1a also blocked cartilage formation. In light of the results, the present study suggests a novel function of ff1a in chondrocyte development.

  • 287.
    Kramarev, Nikolay
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Development and integration of a control system forflexible grippers2010Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Various robotic grippers support or even replace human beings on particular tasks, for example, different industrial applications. However, in some cases complex tasks are required and specifications of the industrial gripper should be more advanced. The adjustment for dynamic environment should be done automatically without a human intervention in a control process. The aim of this master’s project was to develop a control software system for given mechanical gripper prototype developed in the AASS research lab. Gripper control program was implemented by using Galil motion control hardware and Galil specific low-level programming language. Gripper was equipped with tactile sensors on fingertips to adjust a grasping behavior for objects with different shapes and sizes. In this thesis the control system for gripper device as well as its integration into the ``intelligent arm´´system was implemented. The ``intelligent arm´´system is an ABB IRB 140 industrial robotic manipulator with IRC5 controller and motion capture system installed in the AASS research lab. Communication between Galil and IRC5 controllers allowed the gripper to be managed by IRC5. On the other hand, gripper could communicate its condition into IRC5 and therefore affect the arm motions.

     

  • 288.
    Kreida, Stefan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Chimeric MOMP: Expression of a Chlamydia Vaccine Candidate in Arabidopsis thaliana and Escherichia coli2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Introduction

    Yearly, 90 million people are infected with C. trachomatis. Even though it is easily treated with antibiotics the often-asymptomatic infection often spreads prior to detection. A vaccine is therefore of great interest. A chimeric major outer membrane protein (MOMP) of C. trachomatis has in earlier studies proved to contain the epitopes necessary for immunization. In this thesis the chimeric MOMP gene was cloned and expressed in E. coli. Furthermore, the expression of the protein was analyzed in previously transformed A. thaliana.

    Materials and Methods

    The chimeric MOMP gene was cloned into E.coli. Following vector amplification, the gene was expressed and the protein purified by affinity chromatography. 

    Seeds from different lines of previously transformed A. thaliana were screened by PCR. Hits were then analyzed by western blot. 

    Results

    The results show successful cloning and expression of the chimeric MOMP gene in E. coli. The following protein purification did result in purified protein, however in low concentration.

    For the A.thaliana lines, the presence and correct orientation of the gene was verified in some of the lines screened. The B7 line was verified to express the protein.

    Discussion

    The low concentration of purified protein in E.coli was probably due to un-optimized imunnoprecipitation conditions. In expression analysis of A. thaliana, purification of plant samples by immunoprecipitation prior to running western blot gave results, whereas running un-purified samples in urea buffer did not, probably due to interfering proteins in wild type plants.

  • 289.
    Kristoffersson, Annica
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lindén, Maria
    Division of Intelligent Sens or Systems, Mälardalen University, Västerås, Sweden .
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Robotic telepresence: a healthcare professionals' perspective2010Inngår i: Abstractproceedings from Medicinteknikdagarna 2010, 2010Konferansepaper (Annet vitenskapelig)
  • 290.
    Kristoffersson, Annica
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Severinson Eklundh, Kerstin
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    An exploratory study of health professionals' attitudes about robotic telepresence technology2011Inngår i: Journal of technology in human services, ISSN 1522-8835, E-ISSN 1522-8991, Vol. 29, nr 4, s. 263-283Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This article presents the results from a video-based evaluation study of a social robotic telepresence solution for elderly. The evaluated system is a mobile teleoperated robot called Giraff that allows caregivers to virtually enter a home and conduct a natural visit just as if they were physically there. The evaluation focuses on the perspectives from primary healthcare organizations and collects the feedback from different categories of health professionals. The evaluation included 150 participants and yielded unexpected results with respect to the acceptance of the Giraff system. In particular, greater exposure to technology did not necessarily increase acceptance and large variances occurred between the categories of health professionals. In addition to outlining the results, this study provides a number of indications with respect to increasing acceptance for technology for elderly.

  • 291.
    Kristoffersson, Annica
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    User-centered evaluation of robotic telepresence for an elderly population2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The goal of our studies is to iteratively refine prototypes of the robot by involving end users in development cycles of the prototype throughout the project. The evaluations will be conducted with the aim of maximizing usability across geographic, demographic and cultural boundaries, as well as diverse home environments and user preferences and attitudes. The project ExCITE focuses on end users’ perspectives when using a robotic telepresence platform, the Giraff. The Giraff system consists of a tiltable screen and web camera mounted on a moveable robotic base that can be teleoperated. Our application area is elder care. We motivate the use of telepresence in elder care as a way to ensure safety, facilitate independent living and enhance social interaction.

  • 292.
    Krug, Robert
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dimitrov, Dimitar
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Charusta, Krzysztof
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Iliev, Boyko
    Örebro universitet, Akademin för naturvetenskap och teknik.
    On the efficient computation of independent contact regions for force closure grasps2010Inngår i: IEEE/RSJ 2010 International Conference on Intelligent Robots and Systems (IROS 2010), IEEE conference proceedings, 2010, s. 586-591Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Since the introduction of independent contact regions in order to compensate for shortcomings in the positioning accuracy of robotic hands, alternative methods for their generation have been proposed. Due to the fact that (in general) such regions are not unique, the computation methods used usually reflect the envisioned application and/or underlying assumptions made. This paper introduces a parallelizable algorithm for the efficient computation of independent contact regions, under the assumption that a user input in the form of initial guess for the grasping points is readily available. The proposed approach works on discretized 3D-objects with any number of contacts and can be used with any of the following models: frictionless point contact, point contact with friction and soft finger contact. An example of the computation of independent contact regions comprising a non-trivial task wrench space is given.

  • 293.
    Kärrman, Anna
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Domingo, Jose L.
    Lab Toxicol & Environm Hlth, Univ Rovira & Virgili, Reus Catalonia, Spain.
    Llebaria, Xavier
    Dept Hlth, Hlth Protect Agcy, Barcelona Catalonia, Spain.
    Nadal, Marti
    Lab Toxicol & Environm Hlth, Univ Rovira & Virgili, Reus Catalonia, Spain.
    Bigas, Esther
    Dept Hlth, Hlth Protect Agcy, Barcelona Catalonia, Spain.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lindström, Gunilla
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Biomonitoring perfluorinated compounds in Catalonia, Spain: concentrations and trends in human liver and milk samples2010Inngår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 17, nr 3, s. 750-758Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Perfluorinated compounds (PFCs) are global environmental pollutants that bioaccumulate in wildlife and humans. Laboratory experiments have revealed toxic effects such as delayed development, humoral suppression, and hepatotoxicity. Although numerous human blood levels have been reported, little is known about distribution in the human body. Knowledge about PFC distribution and accumulation in the human body is crucial to understanding uptake and subsequent effects as well as to conduct risk assessments. The present study reports PFC levels in human liver and breast milk from a general population living in Catalonia, Spain. Liver and milk levels are compared to previously reported levels in blood from the same geographic area as well as to other existing reports on human liver and milk levels in other countries. Human liver (n = 12) and milk (n = 10) samples were collected in 2007 and 2008 in Catalonia, Spain. Liver samples were taken postmortem from six males and six females aged 27-79 years. Milk samples were from healthy primipara women (30-39 years old). Both liver and milk were analyzed by solid-phase extraction and ultra-performance liquid chromatography tandem mass spectrometry. Six PFCs were detected in liver, with perfluorooctanesulfonate (PFOS, 26.6 ng/g wet weight) being the chemical with the highest mean concentration. Other PFCs such as perfluorohexanesulfonate (PFHxS), perfluorooctanoic acid (PFOA), and acids with chain lengths up to C11 were also detected, with mean levels ranging between 0.50 and 1.45 ng/g wet weight. On the other hand, PFOS and PFHxS were the only PFCs detected in human milk, with mean concentrations of 0.12 and 0.04 ng/mL, respectively. While milk concentrations were similar to reported levels from other countries, liver samples contained more PFCs above quantification limits and higher PFOS concentrations compared to the only two other reports found in the literature. Differences between the results of the present study and those concerning previous investigations can be due to declining levels of some PFCs, which have been reported for the USA. The relationship between PFC concentrations in human liver, milk, and blood was assessed using blood concentrations previously determined in Catalonia. Those levels resulted in liver/serum ratios of 1.7:1, 1.4:1, and 2.1:1 for PFOS, perfluorodecanoic acid, and perfluoroundecanoic acid, respectively. Accumulation in liver is suggested for PFOS and the perfluorocarboxylic acids with carbon chain lengths C9, C10, and C11. For PFOA and PFHxS, fivefold and 14-fold higher concentrations, respectively, were seen in serum as compared to liver. The mean concentration of PFOS and PFHxS in milk was only 0.8% and 0.6% of the reported mean serum level, respectively. The results of the present study show that several PFCs could be detected in human liver samples of subjects living in Tarragona. Concerning human milk, the mechanism by which PFCs are transferred from mother's blood to breast milk is still unclear. Considering that PFCs are strongly bound to the protein fraction in blood, the possibility of PFCs entering the milk and accumulating to levels observed in maternal plasma is limited. Interestingly, the potential accumulation difference for PFCs with different chain lengths might be of great importance for risk assessment. Continuing studies on the distribution of different PFCs in human tissue are therefore justified.

  • 294.
    Kärrman, Anna
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Elgh-Dalgren, Kristin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lafossas, C.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Moskeland, T.
    Environmental levels and distribution of structural isomers of perfluoroalkyl acids after aqueous fire-fighting foam (AFFF) contamination2011Inngår i: Environmental Chemistry, ISSN 1448-2517, E-ISSN 1449-8979, Vol. 8, nr 4, s. 372-380Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The environment (soil, water, sediment, fish, crab and mussel) around a training facility using aqueous film forming foams (AFFFs) was studied with respect to perfluorinated alkyl acids (PFAAs) and 6 : 2 fluorotelomer sulfonate (FTS) and their structural isomers. High levels of many PFAAs and 6 : 2 FTS were detected in soil, seepage water, sediment and fish liver. Structural isomers were found for sulfonates, except PFBuS, and for PFOA. Quantification using authentic standards revealed an isomer pattern of 63% linear PFOS (L-PFOS) and 80% linear PFOA (L-PFOA) in the soil at the contamination site, which indicated a source produced by electrochemical fluorination (ECF). The 6 : 2 FTS was 100% linear in all compartments thus coming from a telomerisation product. Enrichment of the linear structure of PFOS and PFOA in soil was seen with increasing distance from the training centre, and an enrichment of branched isomers for both compounds could be found in the seepage water. Sorption to sediment and accumulation in fish liver led to an enrichment of L-PFOS whereas all PFOA remained in the water body.

  • 295.
    Kärrman, Anna
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Harada, Kouji H.
    Inoue, Kayoko
    Takasuga, Takumi
    Ohi, Etsumasa
    Koizumi, Akio
    Relationship between dietary exposure and serum perfluorochemical (PFC) levels-A case study2009Inngår i: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 35, nr 4, s. 712-717Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Daily dietary intake of perfluorinated chemicals (PFCs) in relation to serum levels was assessed by determination of nine PFCs including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in matched daily diet duplicates and serum samples. Diet and serum were collected in year 2004 from 20 women in Osaka and Miyagi, Japan. Only PFOS and PFOA were detected in the diet samples and no significant difference between cities was seen. After adjusted by water content, diet concentration of PFOA was significantly higher in Osaka. The median daily intake calculated using the measured diet concentrations was 1.47 ng PFOS/kg b.w. and 1.28 ng PFOA/kg b.w. for Osaka, and 1.08 ng PFOS/kg b.w. and 0.72 ng PFOA/kg b.w. for Miyagi. A significant difference between cities was seen for the serum concentrations with median of 31 ng/mL PFOS and PFOA in Osaka, compared to 14 ng/mL PFOS and 4.6 ng/mL PFOA in Miyagi. Carboxylates such as perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUnDA) were also detected in serum at median levels 6.9 ng/mL and 3.2 ng/mL (Osaka), and 2.8 ng/mL and 5.1 ng/mL (Miyagi). Based on one-compartment model under steady state, dietary intake of PFOS and PFOA accounted for only 22.4% and 23.7% of serum levels in Osaka females, and in contrast 92.5% and 110.6% in Miyagi females, respectively. (C) 2009 Elsevier Ltd. All rights reserved.

  • 296. Labet, Vanessa
    et al.
    Grand, Andre
    Morell, Christophe
    Cadet, Jean
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Mechanism of nitric oxide induced deamination of cytosine2009Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 11, nr 14, s. 2379-2386Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A five-step mechanism is proposed for the NO center dot-induced deamination of cytosine. It has been investigated using DFT calculations, including both explicit water molecules and a bulk solvent model to mimic an aqueous environment. According to this mechanism, cytosine first undergoes tautomerization with the assistance of a water molecule from the bulk. A NO+ cation produced by the autooxidation of NO center dot is subsequently added to the exocyclic imino group of the cytosine imine tautomer. The resulting adduct is able to undergo a tautomerization step with the participation of a water molecule to produce a cytosine in which a -N2OH group is attached to carbon C4. Protonation of the oxygen of the latter gives a water molecule which dissociates instantaneously, leading to a pyrimidinic diazonium cation. This constitutes the rate-determining step of the mechanism with an activation free energy of 92.6 kJ mol(-1). The last step, which is highly exergonic, represents the driving force of the reaction. It is the substitution of the -N-2(+) terminal group by a water molecule which simultaneously allows the transfer of one of the two hydrogens to the bulk. Thus, the two products of the reaction consist of a nitrogen molecule and the enol tautomer of uracil in equilibrium with the keto form.

  • 297. Labet, Vanessa
    et al.
    Morell, Christophe
    Cadet, Jean
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Grand, Andre
    Hydrolytic Deamination of 5-Methylcytosine in Protic Medium: A Theoretical Study2009Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 113, nr 11, s. 2524-2533Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mechanism for the deamination reaction of 5-methylcytosine with H2O in protic medium was investigated using DFT calculations at the B3LYP/6-311G(d,p) level of theory. Two pathways were found. Pathway 5mA is a two-step mechanism where the N3-protonated 5-MeCyt undergoes a nucleophilic attack to carbon C4 by a water dimer before the elimination of an ammonium cation. Pathway 5mB is a three-step mechanism where neutral 5-MeCyt is directly attacked by a water dimer. The resulting intermediate is then protonated to allow the elimination of an ammonium cation. Both pathways lead to the formation of thymine in interaction with an ammonium cation and a water molecule. Pathway 5mA can explain the spontaneous deamination of 5-MeCyt in protic medium at acidic pH, whereas pathway 5mB is more representative of the deamination in protic medium at neutral pH. The nucleophilic addition of the water dimer is rate-determining in both pathways and is associated with an activation free energy in aqueous solution of 137.4 kJ/mol for pathway 5mA and 134.1 kJ/mol for pathway 5mB. This latter value is in agreement with the experimental observation that 5-MeCyt deaminates four- to fivefold faster than Cyt at neutral pH. Both electrostatic and electron-transfer contributions appear to have significant importance. In vacuum, the former one dominates when the substrate is positively charged and the latter one when it is neutral.

  • 298.
    Labet, Vanessa
    et al.
    CEA, UJF, Lab Les Acides Nucle,INAC,SCIB,UMR E 3, CEA Grenoble, Grenoble, France.
    Morell, Christophe
    CEA, UJF, Lab Les Acides Nucle,INAC,SCIB,UMR E 3, CEA Grenoble, Grenoble, France.
    Douki, Thierry
    CEA, UJF, Lab Les Acides Nucle,INAC,SCIB,UMR E 3, CEA Grenoble, Grenoble, France.
    Cadet, Jean
    CEA, UJF, Lab Les Acides Nucle,INAC,SCIB,UMR E 3, CEA Grenoble, Grenoble, France.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Grand, Andre
    CEA, UJF, Lab Les Acides Nucle,INAC,SCIB,UMR E 3, CEA Grenoble, Grenoble, France.
    Hydrolytic Deamination of 5,6-Dihydrocytosine in a Protic Medium: A Theoretical Study2010Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 114, nr 4, s. 1826-1834Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mechanism for the deamination reaction of 5,6-dihydrocytosine with H2O in a protic medium was investigated by DFT calculations at the B3LYP/6-311G(d,p) level of theory as a model reaction for the deamination reaction of 5,6-saturated cytosine derivatives. Two pathways were found. Pathway dhA, which can explain the deamination in it protic Medium at acidic pH, and pathway dhBt, more representative of the reaction in a protic medium at neutral pH. Pathway dhA is a two-step mechanism initiated by the nucleophilic addition of a water molecule to carbon C4 of N3-protonated 5,6-dihydrocytosine with the assistance of a second water molecule, followed by elimination of ail ammonium cation to form 5.6-dihydrouracil. The nucleophilic addition is rate-determining, with ail activation free energy of 116.0 kJ/mol in aqueous solution. Pathway dhBt is a four-step mechanism which starts with the water-assisted tautomerization of 5,6-dihydrocytosine to form the imino tautomer. This intermediate undergoes nucleophilic addition of water to carbon C4, which after protonation eliminates ail ammonium cation, as in pathway dhA. The nucleophilic addition is again rate-determining, with ail activation free energy of 113.3 kJ/mol in aqueous solution. The latter value is about 25 kJ/mol lower than its Counterpart for cytosine, in agreement with the experimental observation that 5,6-saturated cytosine derivatives exhibit a much shorter lifetime in aqueous solution than their unsaturated Counterparts. The evaluation of reactivity indices derived from conceptual DFT leads to the conclusion that this lower activation free energy can be attributed to a larger local electrophilic power of carbon C4 in 5.6-saturated derivatives.

  • 299. Lal, V.V.
    et al.
    Aalbersberg, W.G.
    Fiedler, Heidelore
    United Nations Environment Programme (UNEP) Chemicals Branch, Châtelaine GE, Switzerland.
    de Boer, J.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    POPs in developing countries: human milk analysis at Pacific reference laboratory in Fiji Islands2011Inngår i: Organohalogen Compounds, ISSN 1026-4892, Vol. 73, s. 789-791Artikkel i tidsskrift (Fagfellevurdert)
  • 300.
    Lanner, Henrik
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Edlund, Per
    Örebro universitet, Akademin för naturvetenskap och teknik.
    WEBBASERAT API2009Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Flex Datasystem är ett Örebrobaserat IT-företag som utvecklar personalsystem, till exempel lön - och tidsredovisning. En del av Flex kunder använder till exempel Flex tidsredovisning för in- och utstämpling men ett annat system för lön. För att inte behöva ha samma information om personalen i flera olika databaser efterfrågade Flex ett kompletterande webbaserat API till deras nuvarande personalsystem.

    Vår uppgift gick delvis ut på att ta fram information om hur detta API skulle kunna implementeras och även att göra själva implementationen.

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