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  • 1451.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Mansouri, Masoumeh
    Örebro University, School of Science and Technology.
    Petkov, Vilian
    Technical University of Varna, Varna, Bulgaria.
    A Loosely-Coupled Approach for Multi-Robot Coordination, Motion Planning and Control2018Conference paper (Refereed)
  • 1452.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Cesta, Amedeo
    The role of different solvers in planning and scheduling integration2003In: AI*IA 2003: Advances in Artificial Intelligence, Springer Berlin/Heidelberg, 2003, Vol. 2829, p. 362-374Conference paper (Refereed)
    Abstract [en]

    This paper attempts to analyze the issue of planning and scheduling integration from the point of view of information sharing. This concept is the basic bridging factor between the two realms of problem solving. In fact, the exchange of each solver’s point of view on the problem to be solved allows for a synergetic effort in the process of searching the space of states. In this work, we show how different solving strategies cooperate in this process by varying the degree of integration of the combined procedure. In particular, the analysis exposes the advantage of propagating sets of partial plans rather than reasoning on sequential state space representations. Also, we show how this is beneficial both to a component-based approach (in which information sharing occurs only once) and to more interleaved forms of integration.

  • 1453.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    A constraint-based approach for multiple non-holonomic vehicle coordination in industrial scenarios2012In: ICAPS 2012 Workshop on Combining Task and Motion Planning for Real-World Applications, 2012, p. 45-52Conference paper (Refereed)
    Abstract [en]

    Autonomous vehicles are already widely used in industrial logisticsettings. However,  applications still lack flexibility, andmany steps of the deployment process are hand-crafted byspecialists. Here, we preset a new, modular paradigm whichcan fully solve logistic problems for AGVs, from high-leveltask planning to vehicle control. In particular, we focus ona new method for multi-robot coordination which does notrely on pre-defined traffic rules and in which feasible andcollision-free trajectories are calculated for every vehicle accordingto mission specifications. Also, our solutions canbe adapted on-line to exogenous events, control failures, orchanges in mission requirements.

  • 1454.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Dell’Osa, Francesca
    Centre for Applied Autonomous Sensor Systems ( AASS ).
    Ullberg, Jonas
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    A constraint-based approach for proactive, context-aware human support2012In: Journal of Ambient Intelligence and Smart Environments, ISSN 1876-1364, E-ISSN 1876-1372, Vol. 4, no 4, p. 347-367Article in journal (Refereed)
    Abstract [en]

    In this article we address the problem of realizing a service-providing reasoning infrastructure for pro-active humanassistance in intelligent environments. We propose SAM, an architecture which leverages temporal knowledge represented asrelations in Allen’s interval algebra and constraint-based temporal planning techniques. SAM provides two key capabilities forcontextualized service provision: human activity recognition and planning for controlling pervasive actuation devices. Whiledrawing inspiration from several state-of-the-art approaches, SAM provides a unique feature which has thus far not been addressedin the literature, namely the seamless integration of these two key capabilities. It does so by leveraging a constraint-basedreasoning paradigm whereby both requirements for recognition and for planning/execution are represented as constraints andreasoned upon continuously.

  • 1455.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    On mission-dependent coordination of multiple vehicles under spatial and temporal constraints2012In: IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Institute of Electrical and Electronics Engineers (IEEE), 2012, p. 5262-5269Conference paper (Refereed)
    Abstract [en]

    Coordinating multiple autonomous ground vehicles is paramount to many industrial applications. Vehicle trajectories must take into account temporal and spatial requirements, e : g :; usage of floor space and deadlines on task execution. In this paper we present an approach to obtain sets of alternative execution patterns (called trajectory envelopes) which satisfy these requirements and are conflict-free. The approach consists of multiple constraint solvers which progressively refine trajectory envelopes according to mission requirements. The approach leverages the notion of least commitment to obtain easily revisable trajectories for execution.

  • 1456.
    Pecora, Federico
    et al.
    Örebro University, School of Science and Technology.
    Rasconi, Ricardo
    Cortellessa, Gabriella
    Cesta, Amedeo
    User-oriented problem abstractions in scheduling: customization and reuse in scheduling software architectures2006In: Innovations in Systems and Software Engineering, ISSN 1614-5046, Vol. 2, no 1, p. 1-16Article in journal (Refereed)
    Abstract [en]

    In this paper we describe a modeling framework aimed at facilitating the customization and deployment of artificial intelligence (AI) scheduling technology in real-world contexts. Specifically, we describe an architecture aimed at facilitating software product line development in the context of scheduling systems. The framework is based on two layers of abstraction: a first layer providing an interface with the scheduling technology, on top of which we define a formalism to abstract domain-specific concepts. We show how this two-layer modeling framework provides a versatile formalism for defining user-oriented problem abstractions, which is pivotal for facilitating interaction between domain experts and technologists. Moreover, we describe a graphical user interface (GUI)-enhanced tool which allows the domain expert to interact with the underlying core scheduling technology in domain-specific terms. This is achieved by automatically instantiating an abstract GUI template on top of the second modeling layer.

  • 1457.
    Pedersen, Helle Krogh
    et al.
    Novo Nordisk Foundation Center for Protein Research, Disease Systems Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland.
    Gudmundsdottir, Valborg
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens Lyngby, Denmark.
    Nielsen, Henrik Bjorn
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens Lyngby, Denmark.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. Turku Centre for Biotechnology, Åbo Akademi University, Turku, Finland; Turku Centre for Biotechnology, University of Turku, Turku, Finland; VTT Technical Research Centre of Finland, Espoo, Finland.
    Nielsen, Trine
    Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
    Jensen, Benjamin A. H.
    Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
    Forslund, Kristoffer
    European Molecular Biology Laboratory, Heidelberg, Germany.
    Hildebrand, Falk
    European Molecular Biology Laboratory, Heidelberg, Germany; Department of Bioscience Engineering, Vrije Universiteit Brussel, Brussels, Belgium; Center for the Biology of Disease, VIB, Leuven, Belgium.
    Prifti, Edi
    MGP MetaGénoPolis, INRA, Université Paris-Saclay, Jouy en Josas, France; Institute of Cardiometabolism and Nutrition (ICAN), Paris, France.
    Falony, Gwen
    Center for the Biology of Disease, VIB, Leuven, Belgium; Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.
    Le Chatelier, Emmanuelle
    MGP MetaGénoPolis, INRA, Université Paris-Saclay, Jouy en Josas, France.
    Levenez, Florence
    MGP MetaGénoPolis, INRA, Université Paris-Saclay, Jouy en Josas, France.
    Dore, Joel
    MGP MetaGénoPolis, INRA, Université Paris-Saclay, Jouy en Josas, France; Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.
    Mattila, Ismo
    VTT Technical Research Centre of Finland, Espoo, Finland; Steno Diabetes Center, Gentofte, Denmark.
    Plichta, Damian R.
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens, Lyngby, Denmark.
    Pöhö, Paivi
    VTT Technical Research Centre of Finland, Espoo, Finland; Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
    Hellgren, Lars I.
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens, Lyngby, Denmark.
    Arumugam, Manimozhiyan
    Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
    Sunagawa, Shinichi
    European Molecular Biology Laboratory, Heidelberg, Germany; Institute of Microbiology, ETH Zurich, Zurich, Switzerland.
    Vieira-Silva, Sara
    Center for the Biology of Disease, VIB, Leuven, Belgium; Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.
    Jørgensen, Torben
    Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Research Centre for Prevention and Health, Centre for Health, Capital Region, Glostrup Hospital, Glostrup, Denmark.
    Holm, Jacob Bak
    Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
    Trost, Kajetan
    Steno Diabetes Center, Gentofte, Denmark.
    Kristiansen, Karsten
    Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; BGI-Shenzhen, Shenzhen, China.
    Brix, Susanne
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens, Lyngby, Denmark.
    Raes, Jeroen
    Department of Bioscience Engineering, Vrije Universiteit Brussel, Brussels, Belgium; Center for the Biology of Disease, VIB, Leuven, Belgium; Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium.
    Wang, Jun
    Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark; BGI-Shenzhen, Shenzhen, China; Princess Al Jawhara Albrahim Center of Excellence in the Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia; Macau University of Science and Technology, Taipa, China; Department of Medicine and State Key Laboratory of Pharmaceutical Biotechnology, University of Hong Kong, Hong Kong, China.
    Hansen, Torben
    Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.
    Bork, Peer
    European Molecular Biology Laboratory, Heidelberg, Germany; Molecular Medicine Partnership Unit, University of Heidelberg and European Molecular Biology Laboratory, Heidelberg, Germany; Max Delbrück Centre for Molecular Medicine, Berlin, Germany; Department of Bioinformatics, University of Wuerzburg, Würzburg, Germany.
    Brunak, Søren
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens, Lyngby, Denmark; Novo Nordisk Foundation Center for Protein Research, Disease Systems Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
    Oresic, Matej
    Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland; VTT Technical Research Centre of Finland, Espoo, Finland; Steno Diabetes Center, Gentofte, Denmark.
    Ehrlich, S. Dusko
    Center for Biological Sequence Analysis, Dept. of Systems Biology, Technical University of Denmark, Kongens Lyngby, Denmark; University of Örebro, Örebro, Sweden.
    Pedersen, Oluf
    Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
    Human gut microbes impact host serum metabolome and insulin sensitivity2016In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 535, no 7612, p. 376-381Article in journal (Refereed)
    Abstract [en]

    Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individuals is characterized by increased levels of branched-chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus are identified as the main species driving the association between biosynthesis of BCAAs and insulin resistance, and in mice we demonstrate that P. copri can induce insulin resistance, aggravate glucose intolerance and augment circulating levels of BCAAs. Our findings suggest that microbial targets may have the potential to diminish insulin resistance and reduce the incidence of common metabolic and cardiovascular disorders.

  • 1458.
    Pedro J, Aphalo
    et al.
    University of Helsinki, Helsinki, Finland.
    Albert, Andreas
    Helmholtz Zentrum, München, Germany.
    McLeod, Andy
    University of Edinburgh, Edinburgh, UK.
    Heikkilä, Anu
    Finnish Meteorological Institute, Helsinki, Finland.
    Gómez, Iván
    López Figueroa, Felix
    University Of Málaga, Málaga, Spain.
    Robson, T Matthew
    University of Helsinki, Helsinki, Finland.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Beyond the visible: a handbook of best practice in plant UV photobiology2012In: Handbook for research on the effects of ultraviolet radiation on plants / [ed] Pedro J Aphalo, Helsingfors universitet, 2012, 1, p. 35-70Chapter in book (Refereed)
    Abstract [en]

    The writing of this handbook started 14 months ago and is the results of the work of six editors and sixteen authors. This version is a preprint prepared for the participants in the 2012 training school of the COST action 5 FA0906 ‘UV4growth’ at University of Málaga. We hope that you find the handbook useful, and that you will alert us of errors, and of difficult to understand sections or paragraphs. Please, send all such comments to mailto:pedro.aphalo@helsinki.fi?subject=TG1HandbookPre01feedback indicating page and line numbers. Many thanks for your help.

  • 1459.
    Pejryd, Lars
    et al.
    Örebro University, School of Science and Technology.
    Beno, Tomas
    University West, Trollhättan, Sweden.
    Carmignato, Simone
    University of Padova, Padova, Italy.
    Computed tomography as a tool for examining surface integrity in drilled holes in CFRP composites2014In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 13, p. 43-48Article in journal (Refereed)
    Abstract [en]

    In light weight structures the joining of composite materials and of composites to metals are key technologies. A manufacturing method associated with joining is the drilling of holes. The hole creation in CRFP through drilling is associated with several defects related to the process, both on the entry and exit sides of the hole and also with dimensional and surface roughness issues of the hole wall. The detection of damage due to the process is not trivial. Especially interesting is non-destructive methods.

    In this work X-ray computed tomography is used to determine defects due to drilling of holes in a CFRP composite using twist drills with different geometrical features at different drilling parameters. The results can be used to establish relationship between different geometrical features of drills in combination with cutting parameters and resulting surface integrity of holes.

  • 1460.
    Pejryd, Lars
    et al.
    Örebro University, School of Science and Technology.
    Hällgren, Sebastian
    Örebro University, School of Science and Technology. Saab Dynamics AB, Karlskoga, Sweden.
    Product- and knowledge centric Additive Manufacturing research in Sweden2016In: 7th Swedish Production Symposium 2016, 2016Conference paper (Refereed)
    Abstract [en]

    Additive Manufacturing (AM) is a new manufacturing method capable of creating complex shapes that previously was not possible or required long lead time tooling. Different AM methods exist, each with their own strength and weaknesses. Research of AM is done by both industry and academia to better understand the AM methods capabilities. This paper categorises AM research methods in product-centric and knowledge-centric research. Through a literature survey, Sweden’s contributions in AM research are highlighted and categorised. Interviews of designers and manufacturers of metal AM parts are done to find the research challenges of AM for Swedish industries today. Parts manufactured during 2015 using Powder Bed Fusion (PBF) AM processes are shown with examples of AM advantages used. Results show that Sweden contributes well to AM research in mainly knowledge-centric research of material properties and microstructure. A large portion of published papers are done by or in cooperation with Swedish industry. AM is industrially used today mainly for prototypes during development but some Swedish industries are designing specifically for AM. By improving part performance, these parts may reach series production. The biggest challenge is the immature process control of the AM processes, causing uncertain part properties.

  • 1461.
    Pejryd, Lars
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Patrik
    Örebro University, School of Science and Technology.
    Hällgren, Sebastian
    Örebro University, School of Science and Technology.
    Kahlin, Magnus
    Linköping University, Linköping, Sweden.
    Non-destructive evaluation of internal defects in additive manufactured aluminium2016Conference paper (Refereed)
  • 1462.
    Pejryd, Lars
    et al.
    Örebro University, School of Science and Technology.
    Larsson, Joakim
    Örebro University, School of Science and Technology.
    Olsson, Mikael
    Dalarna University, Falun, Sweden.
    Process monitoring of wire drawing using vibration sensoring2017In: CIRP - Journal of Manufacturing Science and Technology, ISSN 1755-5817, E-ISSN 1878-0016, Vol. 18, p. 65-74Article in journal (Refereed)
    Abstract [en]

    Automating the detection of processing conditions that may lead to defects in the wire during the wire drawing process is of high interest to the industry. Current practise is based primarily on operator experience. Increasing demands on product quality and process robustness emphasises the need for development of robust in-process detection methods. This work is focusing on investigating the potential of using vibration monitoring to detect process deficiencies or variations that may lead to defects in the product. Wire drawing of a carbon steel in different lubricating situations was used to investigate vibration signal response together with force measurements and surface investigation of the wire product. The results show that vibration measurement is capable of detecting loss of lubrication that leads to poor surface quality of the wire.

  • 1463.
    Penell, Johanna
    et al.
    Dept Med Sci Occupat & Environm Med, Uppsala Univ, Uppsala, Sweden.
    Lind, Lars
    Dept Med Sci, Uppsala Univ, Uppsala, Sweden.
    Fall, Tove
    Mol Epidemiol & Sci Life Lab, Dept Med Sci, Uppsala Univ, Uppsala, Sweden.
    Syvanen, Anne-Christine
    Mol Epidemiol & Sci Life Lab, Dept Med Sci, Uppsala Univ, Uppsala, Sweden.
    Axelsson, Tomas
    Mol Epidemiol & Sci Life Lab, Dept Med Sci, Uppsala Univ, Uppsala, Sweden.
    Lundmark, Per
    Mol Epidemiol & Sci Life Lab, Dept Med Sci, Uppsala Univ, Uppsala, Sweden.
    Morris, Andrew P.
    Wellcome Trust Ctr Human Genet, Univ Oxford, Oxford, England.
    Lindgren, Cecilia
    Wellcome Trust Ctr Human Genet, Univ Oxford, Oxford, England.
    Mahajan, Anubha
    Wellcome Trust Ctr Human Genet, Univ Oxford, Oxford, England.
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Ingelsson, Erik
    Mol Epidemiol & Sci Life Lab, Dept Med Sci, Uppsala Univ, Uppsala, Sweden; Univ Oxford, Wellcome Trust Ctr Human Genet, Oxford, England.
    Lind, P. Monica
    Dept Med Sci Occupat & Environm Med, Uppsala Univ, Uppsala, Sweden.
    Genetic variation in the CYP2B6 Gene is related to circulating 2,2 ',4,4 '-tetrabromodiphenyl ether (BDE-47) concentrations: an observational population-based study2014In: Environmental health, ISSN 1476-069X, E-ISSN 1476-069X, Vol. 13, p. 34-Article in journal (Refereed)
    Abstract [en]

    Background: Since human CYP2B6 has been identified as the major CYP enzyme involved in the metabolism of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and that human 2B6 is a highly polymorphic CYP, with known functional variants, we evaluated if circulating concentrations of a major brominated flame retardant, BDE-47, were related to genetic variation in the CYP2B6 gene in a population sample.

    Methods: In the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study (men and women all aged 70), 25 single nucleotide polymorphisms (SNPs) in the CYP2B6 gene were genotyped. Circulating concentrations of BDE-47 were analyzed by high-resolution gas chromatography coupled to high-resolution mass spectrometry (HRGC/HRMS).

    Results: Several SNPs in the CYP2B6 gene were associated with circulating concentrations of BDE-47 (P = 10(- 4) to 10(-9)). The investigated SNPs came primarily from two haplotypes, although the correlation between the haplotypes was rather high. Conditional analyses adjusting for the SNP with the strongest association with the exposure (rs2014141) did not provide evidence for independent signals.

    Conclusion: Circulating concentrations of BDE-47 were related to genetic variation in the CYP2B6 gene in an elderly population.

  • 1464.
    Penell, Johanna
    et al.
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    Lind, Lars
    Department of Medical Sciences, Cardiovascular epidemiology, Uppsala University, Uppsala, Sweden.
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, R. Monica
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    Persistent organic pollutants are related to the change in circulating lipid levels during a 5 year follow-up2014In: Environmental Research, ISSN 0013-9351, E-ISSN 1096-0953, Vol. 134, p. 190-197Article in journal (Refereed)
    Abstract [en]

    When reporting circulating levels of persistent organic pollutants (POPs), usually lipid-normalized values are given. However, animal experiments and some human data indicate that exposure to POPs may change lipid values. The aim of the present study is to investigate if POP levels can predict future changes in levels of circulating lipids. In the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study, lipids were measured at age 70 and at age 75 in 598 subjects without lipid-lowering medication. Twenty-three different POPs, including 16 polychlorinated biphenyls (PCBs), five organochlorine pesticides, one dioxin (OCDD) and one flame retardant brominated compound (BDE47) were analyzed by high-resolution chromatography coupled to high-resolution mass spectrometry (HRGC/HRMS) at age 70. Strong relationships were seen among the baseline levels of the non-dioxin-like PCBs 194, 206 and 209 and the degree of increase in total serum cholesterol and LDL-cholesterol during the 5 year follow-up. These relationships were generally stronger when lipidnormalized levels were used compared to wet-weight based levels. On the contrary, for two of the pesticides, hexachlorobenzene and trans-nonachlordane, levels were inversely related to the change in LDL-cholesterol, with strongest associations found using wet-weight based levels. PCBs 194, 206 and 209 were inversely related to the change in HDL-cholesterol, in particular for wet-weight based levels. However, these relationships were only significant for wet-weight PCB 194 following adjustment for multiple testing. None of the POPs was related to the change in serum triglycerides. When investigating the association between the change in total serum cholesterol and LDL-cholesterol across different categories of change in BMI, we noted robust results especially in the group with stable BMI, suggesting that the observed relationships were not due to fluctuations in BMI over time. In conclusion, POPs are related to the change in lipids over time, especially LDL-cholesterol. This may explain why POP exposure previously has been linked to atherosclerosis and cardiovascular disease.

  • 1465.
    Perkovic, Mattias
    et al.
    Örebro University, School of Science and Technology.
    Wiklund, Linus
    Örebro University, School of Science and Technology.
    Värdeflödeskartläggning2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company manufactures stainless steel to applications like nuclear plants and tankers. Today they don’t have control over the throughput time and what parameters who are affecting it. The thesis project contains a survey and analysis of the manufacturing process today, how long the lead time is and what’s affecting the lead time. The recommendations that were given are based on the analysis.

    Methods used in the project like interviews and observations has been used to map the process but for data collection has also company reports and the production system been used. During the project, a value stream map has been developed who is a Lean Production tool. The analysis of the manufacturing process is based on the value stream map. The theory used to solve the problem is linked to production such as Lean.

    During the project, it has emerged that the lead time in the production mostly consists of time as the material is in stock between processes. Therefore, conclusions have been drawn that improvement projects should not focus on optimization heat treatment for instance. There is greater potential to reduce other time e.g. inventory time.

  • 1466.
    Perman, Daniel
    Örebro University, School of Science and Technology.
    Optimal väggisoleringstjocklek på hyresfastighet vid begränsad byggyta2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Environmental awareness and increased interest in energy-efficient housing have made the buildings more insulated in Sweden. Usually, it is quite easy to calculate a profit from a greater amount of insulation, in the long term. This is usually the seller’s main argument to why the client should choose the thicker insulation. For a client that wants to build a rental property, it is usually the economy that determines whether a project should be started or not. Hopefully this study will be a help to choose the most economic insulation thickness in walls.

    The purpose of this study is to investigate where the optimum of wall insulation thickness is in an apartment building for renting which is built on a limited area. Quite often there are requirements for a maximum building area from the municipality, which means that the rentable living space will come smaller when the insulation gets thicker.

    Qualitative interviews were used to determinate the common wall constructions which the insulation would be optimized for. These walls were placed in a theoretical reference building in which the energy use were estimated using hand calculations where mathematical expressions of a variety of insulation thickness were used. Thereafter, the prices of the walls were calculated using a spreadsheet program called Sektionsdata. A life cycle cost analysis was performed in which the historical statistics on rents, energy prices and interest rates were used. Finally, the optimal insulation thickness was found for each wall type.

    The wall types chosen were a wall of concrete and brick, a wall of concrete and rendering, a wall of wood and brick and a wall of wood and rendering. Optimal insulation thickness of the wall with concrete and brick ended up at 84mm. For the wall of rendered concrete, the optimal insulation thickness ended up at 88mm. The optimal insulation thickness of the walls of wood could not be found as the wall structure with two and three insulation layers made the walls too isolated in an economic perspective even at a minimal thickness of the layer that was going to be optimized.

    The study shows that with current building codes in Sweden it is profitable to keep down the wall insulation thickness in an apartment building for renting, built on a limited area.

  • 1467.
    Persson, Alexandra
    Örebro University, School of Science and Technology.
    Lässvårigheters påverkan på matematikprestationer2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    According to the PISA research (Skolverket, 2013), Swedish students today show weaker presentations in reading comprehension and mathematics. Many factors have been discussed but neither of reading difficulties or mathematic difficulties has been concerned. According to this, a literature review will be established with the purpose to examine how reading difficulties co-operate with mathematic difficulties and how it may impact on mathematic achievements. The result shows that reading difficulties not always have an impact on mathematic achievements. Some students tend to show weaknesses while others do not; however the combined reading- and mathematic difficulties are shown more often compared to the difficulties on their own. Conclusions that have been made are that more research needs to investigate why only a minority of students with reading difficulties show weaknesses in mathematics, while other do not and why the combined reading- and mathematic difficulties are shown more often.

  • 1468.
    Persson, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Al Moubayed, Samer
    Örebro University, School of Science and Technology. Department for Speech, Music and Hearing (TMH), Royal Institute of Technology (KTH), Stockholm, Sweden.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Fluent human–robot dialogues about grounded objects in home environments2014In: Cognitive Computation, ISSN 1866-9956, E-ISSN 1866-9964, Vol. 6, no 4, p. 914-927Article in journal (Refereed)
    Abstract [en]

    To provide a spoken interaction between robots and human users, an internal representation of the robots sensory information must be available at a semantic level and accessible to a dialogue system in order to be used in a human-like and intuitive manner. In this paper, we integrate the fields of perceptual anchoring (which creates and maintains the symbol-percept correspondence of objects) in robotics with multimodal dialogues in order to achieve a fluent interaction between humans and robots when talking about objects. These everyday objects are located in a so-called symbiotic system where humans, robots, and sensors are co-operating in a home environment. To orchestrate the dialogue system, the IrisTK dialogue platform is used. The IrisTK system is based on modelling the interaction of events, between different modules, e.g. speech recognizer, face tracker, etc. This system is running on a mobile robot device, which is part of a distributed sensor network. A perceptual anchoring framework, recognizes objects placed in the home and maintains a consistent identity of the objects consisting of their symbolic and perceptual data. Particular effort is placed on creating flexible dialogues where requests to objects can be made in a variety of ways. Experimental validation consists of evaluating the system when many objects are possible candidates for satisfying these requests.

  • 1469.
    Persson, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, School of Science and Technology.
    Rajasekaran, Balasubramanian
    Dept Sci & Technol, Ctr Appl Autonomous Sensor Syst AASS, Univ Örebro, Örebro, Sweden.
    Krishna, Vamsi
    Dept Science & Technology, Center for Applied Autonomous Sensor Syst (AASS), Örebro University, Örebro, Sweden.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Alirezaie, Marjan
    Örebro University, School of Science and Technology.
    I would like some food: anchoring objects to semantic web informationin human-robot dialogue interactions2013In: Social Robotics: Proceedings of 5th International Conference, ICSR 2013, Bristol, UK, October 27-29, 2013. / [ed] Guido Herrmann, Martin J. Pearson, Alexander Lenz, Paul Bremner, Adam Spiers, Ute Leonards, Springer, 2013, p. 361-370Conference paper (Refereed)
    Abstract [en]

    Ubiquitous robotic systems present a number of interesting application areas for socially assistive robots that aim to improve quality of life. In particular the combination of smart home environments and relatively inexpensive robots can be a viable technological solutions for assisting elderly and persons with disability in their own home. Such services require an easy interface like spoken dialogue and the ability to refer to physical objects using semantic terms. This paper presents an implemented system combining a robot and a sensor network deployed in a test apartment in an elderly residence area. The paper focuses on the creation and maintenance (anchoring) of the connection between the semantic information present in the dialogue with perceived physical objects in the home. Semantic knowledge about concepts and their correlations are retrieved from on-line resources and ontologies, e.g. WordNet, and sensor information is provided by cameras distributed in the apartment.

  • 1470.
    Persson, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    A Hash Table Approach for Large Scale Perceptual Anchoring2013In: 2013 IEEE INTERNATIONAL CONFERENCE ON SYSTEMS, MAN, AND CYBERNETICS (SMC 2013), 2013, p. 3060-3066Conference paper (Refereed)
    Abstract [en]

    Perceptual anchoring deals with the problem of creating and maintaining the connection between percepts and symbols that refer to the same physical object. When approaching long term use of an anchoring framework which must cope with large sets of data, it is challenging to both efficiently and accurately anchor objects. An approach to address this problem is through visual perception and computationally efficient binary visual features. In this paper, we present a novel hash table algorithm derived from summarized binary visual features. This algorithm is later contextualized in an anchoring framework. Advantages of the internal structure of proposed hash tables are presented, as well as improvements through the use of hierarchies structured by semantic knowledge. Through evaluation on a larger set of data, we show that our approach is appropriate for efficient bottom-up anchoring, and performance-wise comparable to recently presented search tree algorithm.

  • 1471.
    Persson, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Fast Matching of Binary Descriptors for Large-scale Applications in Robot Vision2016In: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 13, article id 58Article in journal (Refereed)
    Abstract [en]

    The introduction of computationally efficient binary feature descriptors has raised new opportunities for real-world robot vision applications. However, brute force feature matching of binary descriptors is only practical for smaller datasets. In the literature, there has therefore been an increasing interest in representing and matching binary descriptors more efficiently. In this article, we follow this trend and present a method for efficiently and dynamically quantizing binary descriptors through a summarized frequency count into compact representations (called fsum) for improved feature matching of binary pointfeatures. With the motivation that real-world robot applications must adapt to a changing environment, we further present an overview of the field of algorithms, which concerns the efficient matching of binary descriptors and which are able to incorporate changes over time, such as clustered search trees and bag-of-features improved by vocabulary adaptation. The focus for this article is on evaluation, particularly large scale evaluation, compared to alternatives that exist within the field. Throughout this evaluation it is shown that the fsum approach is both efficient in terms of computational cost and memory requirements, while retaining adequate retrieval accuracy. It is further shown that the presented algorithm is equally suited to binary descriptors of arbitrary type and that the algorithm is therefore a valid option for several types of vision applications.

  • 1472.
    Persson, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Längkvist, Martin
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Learning Actions to Improve the Perceptual Anchoring of Object2017In: Frontiers in Robotics and AI, E-ISSN 2296-9144, Vol. 3, no 76Article in journal (Refereed)
    Abstract [en]

    In this paper, we examine how to ground symbols referring to objects in perceptual data from a robot system by examining object entities and their changes over time. In particular, we approach the challenge by 1) tracking and maintaining object entities over time; and 2) utilizing an artificial neural network to learn the coupling between words referring to actions and movement patterns of tracked object entities. For this purpose, we propose a framework which relies on the notations presented in perceptual anchoring. We further present a practical extension of the notation such that our framework can track and maintain the history of detected object entities. Our approach is evaluated using everyday objects typically found in a home environment. Our object classification module has the possibility to detect and classify over several hundred object categories. We demonstrate how the framework creates and maintains, both in space and time, representations of objects such as 'spoon' and 'coffee mug'. These representations are later used for training of different sequential learning algorithms in order to learn movement actions such as 'pour' and 'stir'. We finally exemplify how learned movements actions, combined with common-sense knowledge, further can be used to improve the anchoring process per se.

  • 1473.
    Persson, Elin
    Örebro University, School of Science and Technology.
    Mera Favorit matematik 3A: En läromedelsgranskning med utgångspunkt i problemlösning2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is an established opinion that a large part of mathematics education today has its main point in textbooks, so it’s important to review the content of the textbooks because there is no longer any state approval of teaching materials in Sweden. The purpose of the study is to examine a mathematical textbook in grade three to investigate the way and extent to which the textbook allows students to work with problem solving. The survey has been based on a qualitative text analysis and a quantitative content analysis to review, classify and categorize the content of selected and specific parts of “Mera Favorit Matematik 3A” and then review the same section again to determine if the problem assignments requires creative mathematical reasoning to be solved. The result shows that there are clear differences between what the textbook considers is problem solving, and what current studies analysis means are problem solving, based on creative mathematical reasoning.

  • 1474.
    Persson, Elin
    Örebro University, School of Science and Technology.
    Undervisningspraktikens roll i utvecklingen av matematiskt begåvade elever: En systematisk litteraturstudie inom ämnet matematik2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study is through previous research examining how gifted students in mathematics can be supported through the development of teaching. In this research review, the areas of teaching practice design for mathematically gifted students are examined. There is no doubt that gifted students in mathematics need help and support to develop. However, there exist different views of how teaching should be conducted for the benefit of the gifted students. The study's methodology is a literature review, combined with text analysis in which objective values are prioritized. Through a systematic literature review, study results presented two main categories of student development, teaching practice and influencing factors. The research review describes the necessity of the two main categories interacting in teaching of mathematically gifted students. It is found mostly positive results in the development of mathematically gifted students, with a few negative objections, which emphasizes the importance of further research in the area of giftedness and their development. The conclusion is that teaching practice can advantageously be designed with the support of teaching practice and influencing factors.

  • 1475.
    Persson, Josefin
    et al.
    Örebro University, School of Science and Technology.
    Wang, Thanh
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology.
    Organophosphate flame retardants and plasticizers in indoor dust, air and window wipes in newly built low-energy preschools2018In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 628-629, p. 159-168Article in journal (Refereed)
    Abstract [en]

    The construction of extremely airtight and energy efficient low-energy buildings is achieved by using functional building materials, such as age-resistant plastics, insulation, adhesives, and sealants. Additives such as organophosphate flame retardants (OPFRs) can be added to some of these building materials as flame retardants and plasticizers. Some OPFRs are considered persistent, bioaccumulative and toxic. Therefore, in this pilot study, the occurrence and distribution of nine OPFRs were determined for dust, air, and window wipe samples collected in newly built low-energy preschools with and without environmental certifications. Tris(1,3-dichloroisopropyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) were detected in all indoor dust samples at concentrations ranging from 0.014 to 10 μg/g and 0.0069 to 79 μg/g, respectively. Only six OPFRs (predominantly chlorinated OPFRs) were detected in the indoor air. All nine OPFRs were found on the window surfaces and the highest concentrations, which occurred in the reference preschool, were measured for 2-ethylhexyl diphenyl phosphate (EHDPP) (maximum concentration: 1500 ng/m2). Interestingly, the OPFR levels in the environmental certified low-energy preschools were lower than those in the reference preschool and the non-certified low-energy preschool, probably attributed to the usage of environmental friendly and low-emitting building materials, interior decorations, and consumer products.

  • 1476.
    Persson, Patrik
    et al.
    Örebro University, School of Science and Technology.
    Nilsson, Joakim
    Örebro University, School of Science and Technology.
    Val av stommaterial: Vilket är det mest fördelaktiga stommaterialet vid uppförande av en hallbyggnad?2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When constructing an industrial- or hall building, the most common framework materials thatis used are wood, steel or concrete. Due to an assignment from Byggnadstekniska Byrån ABhas a document been created that makes it possible to investigate how the final costs is af-fected by gapes in between elements and which used foundation. And this with steel as thematerial. The purpose with this essay is to investigate which is the most well fitted materialwhen constructing an industrial- or hall building wood, steel or concrete. Information aboutthe different materials has been collected by litterateurs and by different internet pages. Aseries of interviews has been made with key persons for respectively material. Then the in-formation from interviews and the theory was combined. After combining the theory and theinterviews has a result by different characteristic qualities been made with different gradesdepended on how good the different materials match the different qualities. The combinedgrades shows that steel is the material most fitted when constructing an industrial- or hallbuilding.

  • 1477.
    PERSSON SANDQVIST, NIKLAS
    et al.
    Örebro University, School of Science and Technology.
    KATARDZIC, ADNAN
    Örebro University, School of Science and Technology.
    Mobil diabetesapplikation2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is about the development of a prototype of a mobile application and a web application that will help diabetes patients in their own treatment and ease diabetes nurses work with their diabetes patients.

     

    The mobile application is a digital version of a diabetes diary used by the Örebro County Council primary care to ease in diabetes treatments.

     

    The report also covers tests with users which were conducted on potential users to get some sort of feedback from groups other than customer and colleagues. Tests with users showed that there was an interest in a mobile application and it was a highly appreciated project.

     

    The web application ease diabetes nurses in their work with their diabetes patients in the way that the web application can display graphs of the patient's blood glucose level. 

  • 1478.
    Persson, Sara
    et al.
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Rotander, Anna
    Örebro University, School of Science and Technology.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Magnusson, Ulf
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Perfluoroalkyl acids in subarctic wild male mink (Neovison vison) in relation to age, season and geographical area2013In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 59, p. 425-430Article in journal (Refereed)
    Abstract [en]

    This study investigates the influence of biological and environmental factors on the concentrations of perfluoroalkyl acids (PFAAs) in a top predator; the American mink Perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluoroalkyl carboxylates (PFCAs) with C-8-C-13 perfluorinated carbon chains were analyzed in livers from wild male mink liver (n = 101) from four areas in Sweden representing two inland environments (rural and highly anthropogenic, respectively) and two different coastal environments. Mean PFOS concentrations were 1250 ng/g wet weight and some mink from the urban inland area had among the highest PFOS concentrations ever recorded in mink (up to 21 800 ng/g wet weight). PFBS was detected in 89% of the samples, but in low concentrations (mean 0.6 ng/g ww). There were significant differences in PFAA concentrations between the geographical areas (p < 0.001-0.01). Age, body condition and body weight did not influence the concentrations significantly, but there was a seasonal influence on the concentrations of perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUnDA) (p < 0.01 and p < 0.05, respectively), with lower concentrations in autumn samples than in samples taken" in the winter and spring. It is thus recommended to take possible seasonal differences into account when using mink exposure data. The overall results suggest that the mink is a suitable sentinel species for assessing and monitoring environmental levels of PFAAs. (C) 2013 The Authors. Published by Elsevier Ltd. All rights reserved.

  • 1479.
    Persson, Sara
    et al.
    Division of Reproduction, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Rotander, Anna
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Brunström, Björn
    Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden.
    Bäcklin, Britt-Marie
    Department of Contaminant Research, Swedish Museum of Natural History, Stockholm, Sweden.
    Magnusson, Ulf
    Division of Reproduction, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Influence of age, season, body condition and geographical area on concentrations of chlorinated and brominated contaminants in wild mink (Neovison vison) in Sweden2013In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 90, no 5, p. 1664-1671Article in journal (Refereed)
    Abstract [en]

    The wild mink has gained acceptance as a sentinel species in environmental monitoring. However, only limited data are available in the literature on factors driving variability in concentrations of organic pollutants in this species. This study characterizes the differences in contaminant concentrations in subcutaneous fat of male mink from four different areas in Sweden and demonstrates how age, season and body condition influence concentrations of polychlorinated biphenyl (PCB) congeners, polybrominated diphenyl ether (PBDE) congeners (including methoxylated forms, MeO-PBDEs), as well as the pesticides dichlorodiphenyldichloroethylene (DDE), chlordane and hexachlorobenzene (HCB). The data were statistically treated using multiple regression and principal component analysis. The Sigma PCB concentration and concentrations of PCB congeners 138, 156, 157, 180,170/190, 189, 194, 206, 209 as well as PBDE 153/154 varied with age. Season had an influence on Sigma PCB, PBDE 47 and PBDE 153/154 concentrations, as well as concentrations of most PCB congeners, with the exception of PCB 101, 110, 141 and 182/187. Lean mink had higher concentrations of most PCBs and PBDEs than mink with larger fat depots. The analyzed pesticides (DDE, oxychlordane, HCB) showed no systematic variation with season, age or body condition. The concentrations of MeO-PBDEs were generally low and 6Me-PBDEO 47 was the most commonly detected MeO-PBDE in mink from marine, brackish and freshwater areas. The results indicate that age, season and body condition are factors that may influence the concentrations of PCBs and PBDEs, and it is thus recommended to take these factors into account when analyzing mink exposure data.

  • 1480.
    Peterson, Mårten
    Örebro University, School of Science and Technology.
    En jämförelse mellan kräppat tissuepapper och okräppat papper innan brottbelastning2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Creped-paper stress-strain curve has higher stiffness until 5 % strain thereafter it becomes less stiff. At manufacturing the creeping process wrinkles the paper that should make the paper less stiff in the beginning of the stress-strain curve and stiffer when the fiber-fiber- connections starts to take up load. A comparison has been made between creped-paper and un-creped-paper, for the benefit to get better knowledge of the importance between the fibers and the creeping process for creped papers material properties. The practical work of the project has been to observe creped-paper and un-creped-paper in a material testing machine while it has been recorded by a usb – microscope - camera. The material testing machine test of creped-paper and un-creped-paper that was executed was standard tests of ISO 12615 - 4: 2005, release-of-load-tests, camera-angle-tests and stable-crack-tests.

    The results from the release-of-load-tests, was that creped-paper gets a significant stiffness increase, that didn’t un-creped-paper get. The air-pockets or craters who are made by the paper-mass that aren’t stuck to the yankee-cylinders adhesive, the craters begins to stretch out during the less stiff part of creped-papers stress-strain-curve. To get good angle usb-microscope-camera footages of the creping-structure, the usb-microscope-camera has to be smaller or the area at the material testing machines grip to grip has to be larger.

  • 1481.
    Peterson, Vikor
    et al.
    Örebro University, School of Science and Technology.
    Zetterlund, Zebastian
    Örebro University, School of Science and Technology.
    Stabilitetsanalyser av ett flerfamiljehus- Analys av fyra metoder att undersöka global stabilitet2018Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Structural engineers nowadays enter projects in the late stages while also receiving fewer hours to do the project planning with. This has led to a shift of focus onto software development and an increase in demand of structural design and calculation software. As this is developing there is still a lack of knowledge regarding how they should be used.The structural division at Strängbetong Örebro are today using a combination of MathCAD, Excel and hand calculation for their precast projects. They have also explored the possibilities of using StruSofts finite element software FEM-Design for their calculations. The structural division remains sceptical due to the complex nature of the program and experiences from previous projects using the software.The purpose of this study is to build an apartment building composed of prefabricated elements and analyse the structural stability of the building using four different methods aided by the software FEM-Design. The program itself relies on the finite element method to solve its calculations. Three of the methods are static ways to view a building while the fourth method is a simplification used for hand calculation the traditional way. The focus of the stability analysis is the overturning of said building. The questions to be answered by this study is how big the difference is between these four methods and why it exists.The building is modelled in FEM-Design and analysed using four different methods: first order elasticity theory, second order elasticity theory, limit load theory and simplifications made using traditional hand calculation. To obtain a reliable result the authors attended a two day course about structural design in FEM-Design. The authors also spent a great amount of time experimenting with the program with a purpose to obtain knowledge of how it works and reacts to a combination of different loads and conditions.The obtained result showcased everything from a minor to a significant difference in results between the methods depending on load case in question. No obvious “worst case scenario” is presented as every analysis results in its own critical scenarios. The conclusion is that each of the methods has its place and should be done to secure the stability of building in question. Additionally, part of the result is the instruction presented of how a stability analysis on a prefabricated framework should be performed with FEM-Design.

  • 1482.
    Petra, Majer
    et al.
    Department of Viticulture, Corvinus University of Budapest, Budapest, Hungary.
    Marija, Vidovic
    Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.
    Czégény, Gyula
    Department of Plant Biology, Institute of Biology, University of Pécs, Pécs, Hungary.
    Veljovic Jovanovic, Sonja
    Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Hideg, Éva
    Department of Plant Biology, Institute of Biology, University of Pécs, Pécs, Hungary.
    Evaluation of procedures for assessing anti- and pro-oxidants in plant samples2016In: Analytical Methods, ISSN 1759-9660, E-ISSN 1759-9679, Vol. 8, no 28, p. 5569-5580Article, review/survey (Refereed)
    Abstract [en]

    Plants as well as other aerobic organisms constantly produce reactive oxygen species (ROS). At regulatedlow concentrations ROS may serve as signal molecules, while in excessive amounts these may causeoxidative damage to biomolecules. Actual cellular concentrations are controlled by a network of variousantioxidants, and acclimation to stress conditions is achieved by a dynamic balance of ROS productionand neutralization. Accordingly, plant stress physiology studies generally include an array of methodstesting the occurrence of ROS as well as evaluating antioxidant capacities. The aim of the present workis to provide an overview of these methods, with special emphasis on avoiding errors that can possiblylead to either inaccurate data or misinterpretations of otherwise correct measurements.

  • 1483.
    Pettersson, Elin
    Örebro University, School of Science and Technology.
    Sustainability Evaluations and Development Challenges of Cacao Farms: A Minor Field Study in Huila, Colombia2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An intensification of 200 000 tonnes of cacao is planned for the Colombian cacao production until 2021. This could lead large negative effects on the Colombian nature and biodiversity if the current smallholdings of agroforestry were abandoned in favour for large monocultures. The main objective for this study was to get general overview regarding sustainability and development challenges of the current cacao farming in Huila, Colombia. This was conducted through a minor field study in the area over eight weeks were five farms were documented together with semi-structured interviews and participatory evaluations with the farmers based on the three dimensions; environmental, economical and human. The participatory evaluations were presented by an AMOEBA methodology and even if the subjectivity of the result is a concern for the reliability, the farmers evaluations have highlighted areas of concern as well as for possibilities. Currently, practical improvements such as equipment and low income seemed to be of the greatest concerns but deeper rooted problems, such as the corruption and mistrust to the institutions could probably make a greater impact on the future development of the studied farms. On the positive side, working together in cooperatives has implicated to risen the social sustainability due to more contact and support between farmers.

  • 1484.
    Pettersson, Erik
    et al.
    Örebro University, School of Science and Technology.
    Holmberg, Matthias
    Örebro University, School of Science and Technology.
    KodEd2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project investigated different tools and methods used today in teaching programming. It

    summarizes earlier studies and draws conclusions about how suited they are for the job. The

    accompanying web application would be crafted based on the conclusions made.

     

    The report intends to describe how the web application was constructed, and which methods and tools were used during its development.

     

    The subject of the report is highly relevant today since the Swedish government is discussing the

    introduction of programming classes in the elementary school. Thus demanding both suitable methods and tools.

  • 1485.
    Pettersson, Therese
    Örebro University, School of Science and Technology.
    Laborativ matematik och lärande: En litteraturstudie om en laborativ matematikundervisnings inverkan på elevernas lärande2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are many different models of how mathematics teaching can be conducted. Using laboratory materials in teaching is often portrayed as an effective method to concretize something abstract and increase understanding of mathematics. To examine how a laboratory mathematics teaching affects student learning, I conducted a literature review. 48 articles related to the teaching of physical laboratory materials have been included in the study. The result indicates that there is a spread between different research results, with a slight preponderance of results which demonstrated a positive impact on student learning. The result also indicates that how, when, and what type of laboratory material used is important aspects.

  • 1486.
    Pettersson, Therese
    Örebro University, School of Science and Technology.
    Lärares användning av digitala verktyg i matematikundervisningen: En enkätstudie om lärarnas inställning till och användande av digitala verktyg i matematikundervisningen2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Research has demonstrated many benefits and opportunities to use digital tools in mathematics education. At the same time, it stressed that digital tools are used to a small degree in mathematics teaching. To examine teachers' attitudes to digital tools, how they choose to use them and the factors that influence their choices a survey has been done. Data from the 25 respondents who all teach mathematics in some of the elementary school grades 1-6 have been collected. The result indicates that the teachers include digital tools in a relatively low degree in their teaching. The use of the tools often focuses on the student’s individual practice or whole class situations. Teachers describe that the digital tools increases variability and facilitates individualization of mathematics teaching and increase student motivation. They also stresses that their use of digital tools is limited by problem with the technology and their own knowledge of the field.

  • 1487.
    Pfingsthorn, Max
    et al.
    Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
    Nevatia, Yashodhan
    Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Rathnam, Ravi
    Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
    Markov, Stefan
    Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
    Birk, Andreas
    Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.
    Towards Cooperative and Decentralized Mapping in the Jacobs Virtual Rescue Team2009In: RoboCup 2008: Robot Soccer World Cup XII Vol 5399 / [ed] Iocchi, Luca; Matsubara, Hitoshi; Weitzenfeld, Alfredo; Zhou, Changjiu, Springer Berlin / Heidelberg , 2009, Vol. 5399, p. 225-234Chapter in book (Other academic)
    Abstract [en]

    The task of mapping and exploring an unknown environment remains one of the fundamental problems of mobile robotics. It is a task that can intuitively benefit significantly from a multi-robot approach. In this paper, we describe the design of the multi-robot mapping system used in the Jacobs Virtual Rescue team. The team competed in the World Cup 2007 and won the second place. It is shown how the recently proposed pose graph map representation facilitates not only map merging but also allows transmitting map updates efficiently

  • 1488.
    Pflueger, Maren
    et al.
    Forschergruppe Diabetes e.V., Helmholtz Center Munich, Neuherberg, Germany.
    Seppänen-Laakso, Tuulikki
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Suortti, Tapani
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. VTT Technical Research Centre of Finland, Espoo, Finland.
    Achenbach, Peter
    Forschergruppe Diabetes e.V., Helmholtz Center Munich, Neuherberg, Germany; Institute of Diabetes Research, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany.
    Bonifacio, Ezio
    Deutsche Forschungsgemeinschaft (DFG), Center for Regenerative Therapies Dresden (CRTD)-Cluster of Excellence, Biotechnologisches Zentrum, Dresden, Germany.
    Oresic, Matej
    Örebro University, School of Medical Sciences. VTT Technical Research Centre of Finland, Espoo, Finland.
    Ziegler, Anette-G
    Forschergruppe Diabetes e.V., Helmholtz Center Munich, Neuherberg, Germany; Institute of Diabetes Research, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany.
    Age- and islet autoimmunity-associated differences in amino acid and lipid metabolites in children at risk for type 1 diabetes2011In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 60, no 11, p. 2740-2747Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Islet autoimmunity precedes type 1 diabetes and often initiates in childhood. Phenotypic variation in islet autoimmunity relative to the age of its development suggests heterogeneous mechanisms of autoimmune activation. To support this notion, we examined whether serum metabolite profiles differ between children with respect to islet autoantibody status and the age of islet autoantibody development.

    RESEARCH DESIGN AND METHODS: The study analyzed 29 metabolites of amino acid metabolism and 511 lipids assigned to 12 lipid clusters in children, with a type 1 diabetic parent, who first developed autoantibodies at age 2 years or younger (n = 13), at age 8 years or older (n = 22), or remained autoantibody-negative, and were matched for age, date of birth, and HLA genotypes (n = 35). Ultraperformance liquid chromatography and mass spectroscopy were used to measure metabolites and lipids quantitatively in the first autoantibody-positive and matched autoantibody-negative serum samples and in a second sample after 1 year of follow-up.

    RESULTS: Differences in the metabolite profiles were observed relative to age and islet autoantibody status. Independent of age-related differences, autoantibody-positive children had higher levels of odd-chain triglycerides and polyunsaturated fatty acid-containing phospholipids than autoantibody-negative children and independent of age at first autoantibody appearance (P < 0.0001). Consistent with our hypothesis, children who developed autoantibodies by age 2 years had twofold lower concentration of methionine compared with those who developed autoantibodies in late childhood or remained autoantibody-negative (P < 0.0001).

    CONCLUSIONS: Distinct metabolic profiles are associated with age and islet autoimmunity. Pathways that use methionine are potentially relevant for developing islet autoantibodies in early infancy.

  • 1489.
    Phonying, Supawadee
    Örebro University, School of Science and Technology.
    Manöverhandtag till joystick2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of the degree project was to prepare a proposal for an ergonomic joystick handle for the control of contractor machinery. The handle should be a complement to the company’s existing handle. The purpose of the work is to reduce the repetitive strain injuries of professional machine operators, which among other things can be achieved with the help of the  ergonomic grip and variety of hand movement. This work has been performed according to the design process, from idea to reality, as Stiftelsen Svensk Industridesign describes it. The work started with literature studies, interviews with machine operators and experts in  ergonomics and a field trip. Based on the information several drafts of handle design where sketched on paper and several 3D- clay models were made. Two concepts were developed and judged by a test group. These concepts were also presented to the company. The opinions from the test group and the company were included in the development of the final proposal of the handle. The proposal was processed to obtain a good form with elegant lines and surfaces. To achieve better variations of hand movement, a proposal was made of a rapid  adjustment function. With this function the machine operators will be able to quickly and easily change the angle of the handle. The final model was 3D scanned by an external company. The file received from the company was in form of a STL file. The STL file will be the basis for the development of a CAD model of the joystick handle, though this work will be outside the project. Presentation slides on the handle and fast adjustment were made in Photoshop. The final result met the company’s specified requirements. The design of the handle is based on ergonomic principles and the requirements from customers and company. Small adjustments will be needed in the future towards the final product.

  • 1490.
    Pietiläinen, Kirsi H
    et al.
    Department of Medicine, Division of Internal Medicine, Department of Psychiatry, Obesity Research Unit, Helsinki University Central Hospital, Helsinki, Finland; Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland; Institute for Molecular Medicine Finland, Helsinki, Finland.
    Róg, Tomasz
    Department of Physics, Tampere University of Technology, Tampere, Finland.
    Seppänen-Laakso, Tuulikki
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Virtue, Sam
    Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom.
    Gopalacharyulu, Peddinti
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Tang, Jing
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Rodriguez-Cuenca, Sergio
    Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom.
    Maciejewski, Arkadiusz
    Department of Physics, Tampere University of Technology, Tampere, Finland; Department of Computational Biophysics and Bioinformatics, Jagiellonian University, Kraków, Poland.
    Naukkarinen, Jussi
    Department of Medical Genetics, University of Helsinki, Helsinki, Finland; Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
    Ruskeepää, Anna-Liisa
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Niemelä, Perttu S
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Yetukuri, Laxman
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Tan, Chong Yew
    Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom.
    Velagapudi, Vidya
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Castillo, Sandra
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Nygren, Heli
    VTT Technical Research Centre of Finland, Espoo, Finland.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. VTT Technical Research Centre of Finland, Espoo, Finland.
    Rissanen, Aila
    Department of Medicine, Division of Internal Medicine, Department of Psychiatry, Obesity Research Unit, Helsinki University Central Hospital, Helsinki, Finland.
    Kaprio, Jaakko
    Department of Public Health, Hjelt Institute, University of Helsinki, Helsinki, Finland; Institute for Molecular Medicine Finland, Helsinki, Finland; Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
    Yki-Järvinen, Hannele
    Division of Diabetes, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
    Vattulainen, Ilpo
    Department of Physics, Tampere University of Technology, Tampere, Finland; Department of Applied Physics, School of Science and Technology, Aalto University, Espoo, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark.
    Vidal-Puig, Antonio
    Institute of Metabolic Science, Metabolic Research Laboratories, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom.
    Oresic, Matej
    Institute for Molecular Medicine Finland, Helsinki, Finland; VTT Technical Research Centre of Finland, Espoo, Finland.
    Association of lipidome remodeling in the adipocyte membrane with acquired obesity in humans2011In: PLoS biology, ISSN 1544-9173, E-ISSN 1545-7885, Vol. 9, no 6, article id e1000623Article in journal (Refereed)
    Abstract [en]

    Identification of early mechanisms that may lead from obesity towards complications such as metabolic syndrome is of great interest. Here we performed lipidomic analyses of adipose tissue in twin pairs discordant for obesity but still metabolically compensated. In parallel we studied more evolved states of obesity by investigating a separated set of individuals considered to be morbidly obese. Despite lower dietary polyunsaturated fatty acid intake, the obese twin individuals had increased proportions of palmitoleic and arachidonic acids in their adipose tissue, including increased levels of ethanolamine plasmalogens containing arachidonic acid. Information gathered from these experimental groups was used for molecular dynamics simulations of lipid bilayers combined with dependency network analysis of combined clinical, lipidomics, and gene expression data. The simulations suggested that the observed lipid remodeling maintains the biophysical properties of lipid membranes, at the price, however, of increasing their vulnerability to inflammation. Conversely, in morbidly obese subjects, the proportion of plasmalogens containing arachidonic acid in the adipose tissue was markedly decreased. We also show by in vitro Elovl6 knockdown that the lipid network regulating the observed remodeling may be amenable to genetic modulation. Together, our novel approach suggests a physiological mechanism by which adaptation of adipocyte membranes to adipose tissue expansion associates with positive energy balance, potentially leading to higher vulnerability to inflammation in acquired obesity. Further studies will be needed to determine the cause of this effect.

  • 1491. Pihlblad, Gunilla
    et al.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Från Rådlöst till Shakespeare: Lekebergs Revysällskap 10 år2008 (ed. 1)Book (Other (popular science, discussion, etc.))
  • 1492.
    Piotrowska, Paulina
    Örebro University, School of Science and Technology.
    Kan bekämpningsmedelsrester i druvor orsaka negativa hälsoeffekter?2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Druvor kan innehålla bekämpningsmedel. I denna studie undersöktes om konsumtion av druvor kan orsaka negativa hälsoeffekter. Intervjuer utfördes med kunniga personer inom ämnet. Det finns skilda uppfattningar gällande risker med konsumtion av druvor och det finns aktörer som inte delar uppfattning angående konsumtion av druvor och dess eventuella negativa hälsoeffekter. Syftet med detta arbete är att utröna vilka uppfattningar dessa aktörer har, vad som skiljer dem åt och vad de grundar dessa på. Livsmedelsverkets, Naturskyddsföreningens, Greenpeace och KRAVs uppfattningar studerades genom att intervjua en kunnig person hos var aktör. För att kunna utvärdera dessa uppfattningar har några valda bekämpningsmedel och deras biverkningar undersökts genom studier av befintlig forskning. Urvalet är grundat på de bekämpningsmedel som har överstigit gränsvärdet MRL i druvor. Informationen är tagen från EFSA:s rapport 2012, se bilaga 1. Druvor står för cirka 45 procent av den totala mängden frukt som odlas i världen. Druvodlingar blir lätt angripna av sjukdomar, speciellt svampsjukdomar. Bekämpningsmedel används för att motverka mikroorganismer, växter och djur som orsakar skada. De bekämpningsmedel som framställs har egenskaper som är ämnade att bekämpa en specifik sorts organism och dessa egenskaper kan även vara skadliga för människor. Risker med bekämpningsmedelsrester i livsmedel varierar mellan olika ämnen, beroende på exponeringsgraden och dessa brukar fastställas genom riskbedömningar. Att konsumera livsmedel som har för höga halter bekämpningsmedelsrester kan orsaka negativa hälsoeffekter. Under 2012 togs i Sverige 1 200 prover på bordsdruvor och det konstaterades att 923 av proverna innehöll ett eller flera bekämpningsmedel, samt att 715 av dessa prover innehöll flera olika bekämpningsmedel. Den så kallade Svarta listan visar en sammanställning av partier av livsmedel som Livsmedelsverket har lagt saluförbud på i Sverige.  Aktörernas uppfattningar undersöktes genom intervjuer. Syftet med intervjuerna var att ta reda på om konsumtion av druvor kan orsaka negativa hälsoeffekter, och att ta reda på om arbetets hypotes, att organisationer och föreningar grundar sin uppfattning om bekämpningsmedel på mer än vetenskapliga resultat, stämmer. Slutsatser som dras i denna uppsats är att aktörerna utgår från samma källor men utrycker sig på olika sätt. Livsmedelsverket är Sveriges expertmyndighet, den centrala myndigheten inom området som finansieras statligt, medan Naturskyddsföreningen och Greenpeace är opolitisk ideella natur- och miljöorganisationer.  Livsmedelsverket anser att det inte finns några hälsorisker för normal konsumtion av druvor. Druvor innehåller många nyttiga ämnen. Riskvärderingar har utförts och Livsmedelsverket gör exponeringsberäkningar för den svenska marknaden. Druvor konsumeras ofta av barn och eftersom druvor ofta innehåller bekämpningsmedelsrester utförs därför ca 70-100 s.k. stickprovskontroller per år. Naturskyddsföreningen anser att konsumenter bör välja ekologiska druvor, om möjligheten finns, eftersom det minskar riskerna för negativa miljö- och hälsoeffekter hos de som arbetar i vingårdar och hos konsumenterna, trots att bekämpningsmedelsrester i druvor är låga. Naturskyddsföreningen och Greenpeace utgår från försiktighetsprincipen eftersom de båda aktörerna tycker att det finns för lite forskning för att kunna avgöra om det är hälsofarligt att konsumera livsmedel som är konventionella. Medan KRAV uttalar sig genom att säga att det kan finnas möjlighet till att livsmedel med bekämpningsmedel kan vara hälsofarliga, men det kan man inte bevisa med dagens forskning. Aktörerna förlitar sig på samma informationskällor i många av intervjuns besvarade frågor. Enligt de källor som aktörerna använder sig av är risken att drabbas av negativa hälsoeffekter genom konsumtion av druvor minimal, nästan obefintlig. Enligt den kunskap som finns och enligt de riskvärderingar som är utförda, innebär rester av bekämpningsmedel ingen hälsorisk vid normal konsumtion, eller om man skulle äta fler kilo dagligen, eftersom gränsvärdet för specifika bekämpningsmedelsrester är satta med en hög marginal för alla målgrupper.Det tycks alltså som att samtliga undersökta organisationer utom Livsmedelsverket använder sig av andra resonemang och annat än vetenskapligt baserad riskbedömning när man uttalar sig om risker med vindruvor. Försiktighetsprincipen lyfts fram av flera av organisationerna, samt att man uppfattar att det vetenskapliga underlaget inte är tillräckligt för att dra säkra slutsatser. Denna uppfattning tycks till viss del vara orsakad av brist på kunskap i området. 

  • 1493.
    Pomareda, Victor
    et al.
    Intelligent Signal Processing, Department of Electronics, University of Barcelona, Barcelona, Spain.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Abdul Khaliq, Ali
    Örebro University, School of Science and Technology.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Marco, Santiago
    Intelligent Signal Processing, Department of Electronics, University of Barcelona, Barcelona, Spain.
    Chemical source localization in real environments integrating chemical concentrations in a probabilistic plume mapping approach2013In: Proceedings of the 15th International Symposium on Olfaction and Electronic Nose (ISOEN 2013), 2013Conference paper (Refereed)
    Abstract [en]

    Chemical plume source localization algorithms can be classified either as reactive plume tracking or gas distribution mapping approaches. Here, we focus on gas distribution mapping methods where the robot does not need to track the plume to find the source and can be used for other tasks. Probabilistic mapping approaches have been previously applied to real-world data successfully; e.g., in the approach proposed by Pang and Farrell. Instead of the quasi-continuous gas measurement values, this algorithm considers events (detections and non-detections) based on whether the sensor response is above or below a threshold to update recursively a source probability grid map; thus, discarding important information. We developed an extension of this event-based approach, integrating chemical concentrations directly instead of binary information. In this work, both algorithms are compared using real-world data obtained from a photo-ionization detector (PID), a non-selective gas sensor, and an anemometer in real environments. We validate simulation results and demonstrate that the concentration-based approach is more accurate in terms of a higher probability at the ground truth source location, a smaller distance between the probability maximum and the source location, and a more peaked probability distribution, measured in terms of the overall entropy.

  • 1494.
    Poonlapthawee, Sirirat
    Örebro University, School of Science and Technology.
    Gene expression and antibiotic resistance in Escherichia coli from Swedish inland waters2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Extensive use of antibiotics both from human-medicine and veterinary sources are believed to provide selective pressure on bacteria that leads to an increase in antibiotic resistance in environmental waters. Contamination of antibiotic resistant microbes will raise human health risks. Escherichia coli are Gram negative bacilli that belong to the coliform group. E. coli are used as fecal indicators organism (FIO) to determine microbial contamination and water quality. We aimed to investigate the prevalence of antibiotic resistant bacteria in Swedish inland waters and determine the response of uropathogenic E. coli to the environmental waters. Samples were collected in different locations near Örebro Sweden at 4 different time points during 2010-2011. Waters were filtered and FIO were isolated using selective medium. The highest numbers of FIO were detected for both E. coli and enterococci in the river Svartån near the effluent from the wastewater treatment plant (WWTP). Over the two years, 42% and 24% of the antibiotic resistant strains were multi-drug resistant (MDR) E. coli and enterococci, respectively. In addition, 15% of MDR E. coli were extended spectrum beta-lactamase producing and AmpC overproducing strains. A vancomycin resistant E. faecium was also identified. Tetracycline resistance was the most common in FIO isolates. Our study suggests that WWTP distributed FIO and antibiotic resistant bacteria. In a second study we analyzed for the presence of various pharmaceutical residues from lake Mälaren in Västerås Sweden. Some pharmaceutical compounds were present at detectable levels but were removed by the drinking water treatment plant. Quantitative PCR was performed to investigate the effects on genes focused on antibiotic resistance, virulence factors and stress response. Forty one-gene array was developed and tested using tetracycline treatment or environmental water. No significant difference was found when compared to controls in the gene expression profile of bacteria grown in medium prepared with sub-MIC of tetracycline or environmental waters. We concluded that the pharmaceutical levels detected did not exert any significant effects on the E. coli strain tested. From this study, we conclude that MDR bacteria may actually persist in environmental waters in what is considered as a clean urban region. Pharmaceutical pollutants in the inland water did not exert a significant effect on the E. coli, suggesting that MDR strains are released in the effluent of the WWTP rather than induced through selective pressure by the pharmaceuticals contamination.

    List of papers
    1. Antibiotic resistance in fecal indicator bacteria in Hjälmaren lake system
    Open this publication in new window or tab >>Antibiotic resistance in fecal indicator bacteria in Hjälmaren lake system
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Increasing levels of multi-antibiotic resistant bacteria are ound in the environment, causing serious concerns for treatment of infectious diseases. his increase is believed to be due to release of antibiotic resistant bacteria and election pressure resulting from pharmaceuticals in the environment.

    Objectives: We evaluated the presence of multi-antibiotic resistant fecal ndicator bacteria from the surface waters of a recipient river and lake downstream of he wastewater treatment plant (WWTP) in Sweden.

    Methods: Surface waters from Svartån river and Hjälmaren lake in Sweden were ampled in 2010 and 2011. The waters were analyzed for fecal indicator bacteria Escherichia coli, enterococci) by membrane filtration and selective agar plating. E. coli nd enterococci were evaluated by Etest for resistance to tetracycline, chloramphenicol, alidixic acid, trimethoprim-sulfamethoxazole, ciprofloxacin, cefotaxime, ceftazidime, eropenem, imipenem, ampicillin, vancomycin, gentamycin and streptomycin.

    Results: The highest concentration of E. coli and enterococci were found in vartån river at Naturens Hus closest site downstream of the WWTP. Tetracycline resistance as the most prominent in both fecal indicator bacteria. Over the two years, there was 42% (13/31) and 24% (7/29) multi-antibiotic resistant (≥2 antibiotics) E. coli and nterococci, respectively. Furthermore, we identified one ESBL and one AmpC hyperproducing . coli in 2010 and vancomycin (vanA) resistant E. faecium in 2011.

    Conclusions: The presence, of multi-antibiotic resistant strains of fecal ndicator organisms in regions considered predominantly clean, is of great concern. While t currently may not be a major threat in the region, it is demonstrating the accelerating incidence and spread of antibiotic resistance worldwide.

    National Category
    Ecology Microbiology
    Research subject
    Microbiology; Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-28742 (URN)
    Available from: 2013-04-22 Created: 2013-04-22 Last updated: 2017-10-17Bibliographically approved
    2. Gene expression in Escherichia coli CFT073 grown in sub-MIC tetracycline and environmental waters
    Open this publication in new window or tab >>Gene expression in Escherichia coli CFT073 grown in sub-MIC tetracycline and environmental waters
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    We examined the prevalence of fecal indicator bacteria (coliform E. coli and enterococci) for water quality (World Health Organization, 2011, European Enviroment Agency, 2012) and antibiotic resistant E. coli in lake Mälaren from surface water in Björnö Island at Vinterviken bay and in untreated incoming water to Mälarenergi, drinking water treatment plant (DWTP) in Västerås, Sweden. Our studies have demonstrated that the water quality of environmental water was ‘excellent‘ in both surface water at Bjornö in Vinterviken bay and in the untreated incoming water to the DWTP. However, one multi-antibiotic resistant and one antibiotic resistant strain were isolated from the surface waters. Hence antibiotic resistant strains can persist even in low population of fecal bacterial contamination in the waters. Pharmaceutical compounds in the environment are believed to provide a selective pressure for the development of antibiotic resistance in bacteria (Tenover, 2006, Alekshun and Levy, 2007, Mazumdar et al., 2006). Our study demonstrated that pharmaceutical compounds persisted in lake waters with detectable concentrations as others have shown (Godfrey et al., 2007, Loos et al., 2009). Caffeine, naproxen, hydrochlorothiazide, metoprolol and tramadol were present at detectable levels. To study the effect of contaminants on microorganisms, qPCR method was chosen due to its rapid, sensitive and quantitative analyses of gene expression. Thus a qPCR array was designed, to determine the effect of environmental waters on E. coli isolates. Specific genes that were responsible for antibiotic resistance, virulence factors and stress responses were selected. E. coli CFT073 was treated with either sub-MIC levels (0.1 μg/ml) of tetracycline in LB medium or incoming untreated waters to DWTP in LB medium and compared to controls. Gene expression was determined using qPCR. No significant difference in gene response was observed after treatment with sub-MIC of tetracycline or environmental waters. Pharmaceutical compounds which contaminated the water did not appear to exert a significant gene response in the pathogenic E. coli. Pharmaceutical contamination in the water can promote human and animal health risks however the effect of long-term exposure is yet unknown (European Environment Agency, 2011, Wennmalm and Gunnarsson, 2005, Triebskorn et al., 2007). The antibiotic resistant strains likely originated from the WWTP rather than the selective pressure due to pharmaceutical pollutants in the water. 

    National Category
    Biological Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-28743 (URN)
    Available from: 2013-04-22 Created: 2013-04-22 Last updated: 2017-10-17Bibliographically approved
  • 1495.
    Poonlapthawee, Sirirat
    et al.
    Örebro University, School of Science and Technology.
    Kahn, Faisal Ahmad
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Jass, Jana
    Örebro University, School of Science and Technology.
    Gene expression in Escherichia coli CFT073 grown in sub-MIC tetracycline and environmental watersManuscript (preprint) (Other academic)
    Abstract [en]

    We examined the prevalence of fecal indicator bacteria (coliform E. coli and enterococci) for water quality (World Health Organization, 2011, European Enviroment Agency, 2012) and antibiotic resistant E. coli in lake Mälaren from surface water in Björnö Island at Vinterviken bay and in untreated incoming water to Mälarenergi, drinking water treatment plant (DWTP) in Västerås, Sweden. Our studies have demonstrated that the water quality of environmental water was ‘excellent‘ in both surface water at Bjornö in Vinterviken bay and in the untreated incoming water to the DWTP. However, one multi-antibiotic resistant and one antibiotic resistant strain were isolated from the surface waters. Hence antibiotic resistant strains can persist even in low population of fecal bacterial contamination in the waters. Pharmaceutical compounds in the environment are believed to provide a selective pressure for the development of antibiotic resistance in bacteria (Tenover, 2006, Alekshun and Levy, 2007, Mazumdar et al., 2006). Our study demonstrated that pharmaceutical compounds persisted in lake waters with detectable concentrations as others have shown (Godfrey et al., 2007, Loos et al., 2009). Caffeine, naproxen, hydrochlorothiazide, metoprolol and tramadol were present at detectable levels. To study the effect of contaminants on microorganisms, qPCR method was chosen due to its rapid, sensitive and quantitative analyses of gene expression. Thus a qPCR array was designed, to determine the effect of environmental waters on E. coli isolates. Specific genes that were responsible for antibiotic resistance, virulence factors and stress responses were selected. E. coli CFT073 was treated with either sub-MIC levels (0.1 μg/ml) of tetracycline in LB medium or incoming untreated waters to DWTP in LB medium and compared to controls. Gene expression was determined using qPCR. No significant difference in gene response was observed after treatment with sub-MIC of tetracycline or environmental waters. Pharmaceutical compounds which contaminated the water did not appear to exert a significant gene response in the pathogenic E. coli. Pharmaceutical contamination in the water can promote human and animal health risks however the effect of long-term exposure is yet unknown (European Environment Agency, 2011, Wennmalm and Gunnarsson, 2005, Triebskorn et al., 2007). The antibiotic resistant strains likely originated from the WWTP rather than the selective pressure due to pharmaceutical pollutants in the water. 

  • 1496.
    Porseryd, T.
    et al.
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden.
    Caspillo, N. Reyhanian
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, Örebro, Sweden.
    Volkova, K.
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden; Örebro Life Science Center, School of Science and Technology, Örebro University, Örebro, Sweden.
    Elabbas, L.
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden.
    Källman, T.
    National Bioinformatics Infrastructure Sweden, Uppsala University, Uppsala, Sweden; Science for Life Laboratory and Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
    Dinnetz, P.
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology. Örebro Life Science Center.
    Porsch-Hallstrom, I.
    School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden.
    Testis transcriptome alterations in zebrafish (Danio rerio) with reduced fertility due to developmental exposure to 17 alpha-ethinyl estradiol2018In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 262, p. 44-58Article in journal (Refereed)
    Abstract [en]

    17 alpha-Ethinylestradiol (EE2) is a ubiquitous aquatic contaminant shown to decrease fish fertility at low concentrations, especially in fish exposed during development. The mechanisms of the decreased fertility are not fully understood. In this study, we perform transcriptome analysis by RNA sequencing of testes from zebrafish with previously reported lowered fertility due to exposure to low concentrations of EE2 during development. Fish were exposed to 1.2 and 1.6 ng/L (measured concentration; nominal concentrations 3 and 10 ng/L) of EE2 from fertilization to 80 days of age, followed by 82 days of remediation in clean water. RNA sequencing analysis revealed 249 and 16 genes to be differentially expressed after exposure to 1.2 and 1.6 ng/L, respectively; a larger inter-sample variation was noted in the latter. Expression of 11 genes were altered by both exposures and in the same direction. The coding sequences most affected could be categorized to the putative functions cell signalling, proteolysis, protein metabolic transport and lipid metabolic process. Several homeobox transcription factors involved in development and differentiation showed increased expression in response to EE2 and differential expression of genes related to cell death, differentiation and proliferation was observed. In addition, several genes related to steroid synthesis, testis development and function were differentially expressed. A number of genes associated with spermatogenesis in zebrafish and/or mouse were also found to be differentially expressed. Further, differences in non-coding sequences were observed, among them several differentially expressed miRNA that might contribute to testis gene regulation at post-transcriptional level. This study has generated insights of changes in gene expression that accompany fertility alterations in zebrafish males that persist after developmental exposure to environmental relevant concentrations of EE2 that persist followed by clean water to adulthood. Hopefully, this will generate hypotheses to test in search for mechanistic explanations.

  • 1497.
    Posti, Jussi P.
    et al.
    Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, Turku, Finland; Division of Clinical Neurosciences, Department of Rehabilitation and Brain Trauma, Turku University Hospital, Turku, Finland; Department of Neurology, University of Turku, Turku, Finland.
    Dickens, Alex M.
    Turku Centre for Biotechnology, University of Turku, Turku, Finland.
    Orešič, Matej
    Turku Centre for Biotechnology, University of Turku, Turku, Finland.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. Department of Chemistry.
    Tenovuo, Olli
    Division of Clinical Neurosciences, Department of Rehabilitation and Brain Trauma, Turku University Hospital, Turku, Finland; Department of Neurology, University of Turku, Turku, Finland.
    Metabolomics Profiling As a Diagnostic Tool in Severe Traumatic Brain injury2017In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 8, article id 398Article, review/survey (Refereed)
    Abstract [en]

    Traumatic brain injury (TBI) is a complex disease with a multifaceted pathophysiology. Impairment of energy metabolism is a key component of secondary insults. This phenomenon is a consequence of multiple potential mechanisms including diffusion hypoxia, mitochondrial failure, and increased energy needs due to systemic trauma responses, seizures, or spreading depolarization. The degree of disturbance in brain metabolism is affected by treatment interventions and reflected in clinical patient outcome. Hence, monitoring of these secondary events in peripheral blood will provide a window into the pathophysiological course of severe TBI. New methods for assessing perturbation of brain metabolism are needed in order to monitor on-going pathophysiological processes and thus facilitate targeted interventions and predict outcome. Circulating metabolites in peripheral blood may serve as sensitive markers of pathological processes in TBI. The levels of these small molecules in blood are less dependent on the integrity of the blood-brain barrier as compared to protein biomarkers. We have recently characterized a specific metabolic profile in serum that is associated with both initial severity and patient outcome of TBI. We found that two medium-chain fatty acids, octanoic and decanoic acids, as well as several sugar derivatives are significantly associated with the severity of TBI. The top ranking peripheral blood metabolites were also highly correlated with their levels in cerebral microdialyzates. Based on the metabolite profile upon admission, we have been able to develop a model that accurately predicts patient outcome. Moreover, metabolomics profiling improved the performance of the well-established clinical prognostication model. In this review, we discuss metabolomics profiling in patients with severe TBI. We present arguments in support of the need for further development and validation of circulating biomarkers of cerebral metabolism and for their use in assessing patients with severe TBI.

  • 1498.
    Posti, Jussi P.
    et al.
    Turku Brain Injury Centre, Turku University Hospital, Turku, Finland.
    Dickens, Alex
    Turku Centre For Biotechnology, University of Turku, Turku, Finland.
    Takala, Riikka S.
    Perioperative Services, Intensive Care Medicine and Pain, Turku University Hospital, Turku, Finland.
    Ala-Seppälä, Henna
    Department of Neurology, University of Turku, Turku, Finland.
    Mattila, Ismo
    Systems Medicine, Steno Diabetes Center Copenhagen, Gentofte, Denmark.
    Coles, Jonathan P.
    Division of Anaesthesia, University of Cambridge, Cambridge, England.
    Frantzén, Janek
    Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, Turku, Finland.
    Hutchinson, Peter J.
    Division of Neurosurgery, University of Cambridge, Cambridge, England.
    Katila, Ari
    Perioperative Services, Intensive Care Medicine and Pain, Turku University Hospital, Turku, Finland.
    Kyllönen, Anna
    Department of Neurology, University of Turku, Turku, Finland.
    Maanpää, Henna-Riikka
    Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, Turku, Finland.
    Newcombe, Virginia
    Division of Anaesthesia, University of Cambridge, Cambridge, England.
    Outtrim, Joanne
    Division of Anaesthesia, University of Cambridge, Cambridge, England.
    Tallus, Jussi
    Department of Neurology, University of Turku, Turku, Finland.
    Carpenter, Keri L. H.
    Division of Neurosurgery, University of Cambridge, Cambridge, England.
    Menon, David K.
    Division of Anaesthesia, University of Cambridge, Cambridge, England.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. Department Of Chemistry.
    Tenovuo, Olli
    Turku Brain Injury Centre, Turku University Hospital, Turku, Finland.
    Oresic, Matej
    Turku Centre For Biotechnology, University of Turku, Turku, Finland.
    SERUM METABOLITES ASSOCIATE WITH HEAD COMPUTED TOMOGRAPHY FINDINGS FOLLOWING TRAUMATIC BRAIN INJURY2018In: Journal of Neurotrauma, ISSN 0897-7151, E-ISSN 1557-9042, Vol. 35, no 16, p. A67-A67Article in journal (Other academic)
    Abstract [en]

    There is a need to rapidly detect patients with traumatic brain injury (TBI) who require head computed tomography (CT). Given the energy crisis in the brain following TBI, we hypothesized that serum metabolomics would be a useful tool for developing a set of bio-markers to determine the need for CT and to distinguish between different types of injuries observed. Logistic regression models using metabolite data from the discovery cohort (n=144, Turku, Finland) were used to distinguish between patients with traumatic intracranial findings and negative findings on head CT. The resultant models were then tested in the validation cohort (n=66, Cambridge, UK). The levels of glial fibrillary acidic protein and ubiquitin C-terminalhydrolase-L1 were also quantified in the serum from the same patients. Despite there being significant differences in the protein bio-markers in patients with TBI, the model that determined the need for a CT scan validated poorly (AUC=0.64: Cambridge patients). However, using a combination of six metabolites (two amino acids, thre esugar derivatives and one ketoacid) it was possible to discriminate patients with intracranial abnormalities on CT and patients with a normal CT (AUC=0.77 in Turku patients and AUC=0.73 in Cambridge patients). Furthermore, a combination of three metabolites could distinguish between diffuse brain injuries and mass lesions (AUC=0.87 in Turku patients and AUC=0.68 in Cambridge pa-tients). This study identifies a set of validated serum polar metabolites, which associate with the need for a CT scan. Additionally, serum metabolites can also predict the nature of the brain injury. These metabolite markers may prevent unnecessary CT scans, thus reducing the cost of diagnostics and radiation load.

  • 1499.
    Potenza, Andre
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Towards Sliding Autonomy in Mobile Robotic Telepresence: A Position Paper2017Conference paper (Refereed)
    Abstract [en]

    Sliding autonomy is used in teleoperation to adjusting a robot's level of local autonomy to match the user's needs. We claim that sliding autonomy can also improve mobile robotic telepresence, but we argue that existing approaches cannot be adopted to this domain without adequate modifications. We address in particular the question of how the need for autonomy, and its appropriate degree, can be inferred from measurable information.

  • 1500.
    Potenza, Andre
    et al.
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    One Robot and Two Humans: Some Notes on Shared Autonomy in the Case of Robotic Telepresence.2018Conference paper (Refereed)
    Abstract [en]

    Telepresence robots, similar to other teleoperated robots, can benefit strongly from shared autonomyas a way to enhance ease of use for the operator. With ever-increasing capabilities of autonomousrobots, it is crucial to understand what can be automated and under which circumstances. We argue that within a dynamic environment, the allocation of tasks between human and robot should not be fixed, but rather adaptable, taking into account the current state of the environment.

27282930313233 1451 - 1500 of 2000
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