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  • 101.
    Andersson, Joakim
    et al.
    Örebro University, School of Science and Technology.
    Zurita, Arturo
    Örebro University, School of Science and Technology.
    Reducering av tidsslöseri med hjälp av 5S inom Umicore Autocat Sweden AB2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Umicore is a global company that works with materials. The group has some 80 production plants and around 14400 employees around the world. In Sweden they are at two places, one of which is in Karlskoga. Their name is Umicore Autocat Sweden AB. With their, at the present, 37 employees they manufacture catalysts.

     

    The mission was assigned to us by Umicore Autocat Sweden AB and the purpose of it was to suggest improvements that can be used to try to reduce or eliminate time-wasting that take its shape in the production department. At first it was meant that we would help them to introduce the first three steps of 5S. But because of that we miss estimated the time it would take to do this, we agreed with the company to leave it as suggestion for improvements.

     

    The width of the report consists of the current problems that exist in the company production department. Meanwhile there will be methods and recommendations that will enable improvements to these.

     

    In the implementation of this work interviews, literature studies and all files that the company contributed with from previous work with 5S were used. This is to try to find possible solutions. The result of this is presented as some proposed solutions that can help the company to continue with their quality work. The report also consists of a proposal, with analysis and calculations, of a new layout for the bellows, fixtures and Leister. Some of the information that was used in the calculations we received from the production manager in the company.

     

    We believe that our proposals will work as a tool for the company so they keep improving the quality in their production department by continuing to introduce and implement improvements within 5S. For this purpose it demands that the management ensures that the staff is committed, in this case in 5S.

  • 102.
    Andersson, Lena
    et al.
    Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden; Man-Technology-Environment Research Centre (MTM), Department of Science, Örebro University, Örebro, Sweden.
    Bryngelsson, Ing-Liss
    Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Ngo, Yen
    Swedish Institute for Infectious Disease Control, Solna, Sweden.
    Ohlson, Carl-Göran
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Clinical Medicines, Örebro University, Örebro, Sweden; Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Westberg, Håkan
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Exposure assessment and modeling of quartz in Swedish iron foundries for a nested case-control study on lung cancer2012In: Journal of Occupational and Environmental Hygiene, ISSN 1545-9624, E-ISSN 1545-9632, Vol. 9, no 2, p. 110-119Article in journal (Refereed)
    Abstract [en]

    Exposure assessment of quartz in Swedish iron foundries was performed based on historical and present measurement data. To evaluate the exposure response relationship between quartz exposure and lung cancer, we modeled quartz exposure from our database of measurements using determinants job title, time period and company. Based on these modeled exposure data, we conducted a nested case– control evaluation.

    In our database, the overall individual daily time-weighted average (TWA) quartz concentrations of current and historical data varied between 0.0018 and 4.9 mg/m3, averaging 0.083 mg/m3. The job titles with mean TWAs for the whole study period exceeding the European Union recommended occupational exposure limit of 0.05 mg/m3 were fettlers (0.087 mg/m3), furnace and ladle repair (0.42 mg/m3) and maintenance (0.054 mg/m3) workers.

    The mixed model analysis demonstrated significant determinants on the job level for furnace and ladle repair (β=4.06; 95% CI 2.78-5.93). For all jobs significantly higher exposure levels occurred only during the first time period, 1968-1979 (β=2.08; 95% CI 1.75-2.47), and a decreasing but not significant trend was noted for the three following 10 year time periods up to 2006 (β=1.0, 0.96 and 1, respectively). Two iron foundries had significantly higher quartz concentration levels than the others (β=1.31; 95% CI 1.00-1.71 and β=1.63; 95% CI 1.00-2.65, respectively). The individual cumulative quartz exposure measures were categorized in low, medium and high exposure (0.5-<1, 1-1.9 and ≥2 mg/m3 *years, respectively).

    In the nested case-control analysis, we found the highest odds ratios of lung cancer (OR 1.17; 95% CI 0.53-2.55) for the medium exposure group. No dose– response trend or significantly increased risk was determined for our high exposed group (≥2 mg/m3), representing 40 years of exposure at >0.05 mg/m3 of quartz. To conclude, certain foundry workers are still exposed to high levels of quartz, but an increased risk of lung cancer caused by quartz exposure in these Swedish iron foundries could not be confirmed at our exposure levels.

  • 103.
    Andersson, Lena
    et al.
    Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden; Örebro University, Örebro, Sweden.
    Burdorf, Alex
    Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
    Bryngelsson, Ing-Liss
    Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Westberg, Håkan
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Estimating trends in quartz exposure in Swedish iron foundries: predicting past and present exposures2012In: Annals of Occupational Hygiene, ISSN 0003-4878, E-ISSN 1475-3162, Vol. 56, no 3, p. 362-372Article in journal (Refereed)
    Abstract [en]

    Background: Swedish foundries have a long tradition of legally required surveys in the work place that, from the late 1960s onwards, included measurements of quartz. The availability of exposure data spanning almost 40 years presents a unique opportunity to study trends over that time and to evaluate the validity of exposure models based on data from shorter time spans. The aims of this study were (i) to investigate long term trends in quartz exposure over time, (ii) using routinely collected quartz exposure measurements to develop a mathematical model that could predict both historical and current exposure patterns, and (iii) to validate this exposure model with up-to-date measurements from a targeted survey of the industry.

    Methods: Eleven foundries, representative of the Swedish iron foundry industry, were divided into three groups based on the size of the companies, i.e. the number of employees. A database containing 2333 quartz exposure measurements for 11 different job descriptionswas used to create three models that covered time periods which reflected different work conditions and production processes: a historical model (1968– 1989), a development model (1990–2004), and a validation model (2005–2006). A linear mixed model for repeated measurements was used to investigate trends over time. In all mixed models, time period, company size, and job title were included as fixed (categorical) determinants of exposure. The within- and between-worker variances were considered to be random effects. A linear regression analysis was erformed to investigate agreement between the models. The average exposure was estimated for each combination of job title and company size.

    Results: A large reduction in exposure (51%) was seen between 1968 and 1974 and between 1975 and 1979 (28%). In later periods, quartz exposure was reduced by 8% per 5 years at best. In the first period, employees at smaller companies experienced ~50%higher exposure levels than those at large companies, but these differences became much smaller in later years. The furnace and ladle repair job were associated with the highest exposure, with 3.9–8.0 times the average exposure compared to the lowest exposed group. Without adjusting for this autonomous trend over time, predicting early historical exposures using our development model resulted in a statistically significant regression coefficient of 2.42 (R2 5 0.81), indicating an underestimation of historical exposure levels. Similar patterns were seen for other historical time periods. Comparing our development model with our validation model resulted in a statistically significant regression coefficient of 0.31, indicating an overestimation of current exposure levels.

    Conclusion: To investigate long-term trends in quartz exposure over time, overall linear trends can be determined by using mixed model analysis. To create individual exposure measures to predict historical exposures, it is necessary to consider factors such as the time period, type of job, type of company, and company size. The mixed model analysis showed systematic changes in concentration levels, implying that extrapolation of exposure estimates outside the range of years covered by measurements may result in underestimation or overestimation of exposure.

  • 104.
    Andersson, Mattias
    et al.
    Örebro University, School of Science and Technology.
    Berneke, Anders
    Örebro University, School of Science and Technology.
    Basis and a concept for a Paper machine in a laboratory scale2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis studies paper and what it is made of and different ways to manufacture it in a laboratory scale. It also contains a comparison of different ways to dry tissue and which method that suits a small laboratory tissue machine best.

     A small paper machine was found at Metso in Karlstad that was used as a basis for the concept machine. Since the machine at Karlstad used pressing and a cylinder drying method that involves pressing an alternative method to dry the paper had to be chosen.

    For drying tissue there are several methods like, infrared and through air drying. A comparison was made between those methods to find out which suited the specification best.

    The comparison shows that through air drying is the best drying method for the machine.

  • 105.
    Andersson, Oskar
    Örebro University, School of Science and Technology.
    Framgångsrika åtgärdsprogram: En systematisk litteraturstudie som kartlägger faktorer som kan öka måluppfyllelsen i åtgärdsprogramsprocessen i matematik.2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Both from previous research and from the media the documentation form of education plan receives a lot of criticism in terms of both content and design. An education plan must be written if a student is suspected not to achieve current knowledge requirements. It will therefore be important in a subject like mathematics which has a relatively high percentage of students who fails to achieve the knowledge requirements. Therefore it is important that the process with the education plan fulfils its purpose. This systematic literature study aims to identify factors that may increase the effectiveness of education plan process in mathematics. The results and conclusions of this study put forward several different factors that must interact in order to make the educational plan process in mathematics successful. Factors that this study concludes that might have an affect are for example, pupils' and parents' participation and the headmasters’ commitment and volition to participate.

  • 106.
    Andersson, Oskar
    Örebro University, School of Science and Technology.
    Åtgärdsprogram i matematik: Vägen mot kunskapskraven?2015Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Academic year 2013/2014 almost every tenth student in grades 6 lacks passing grade in mathematics. Mathematics is one of the three subjects that a student needs to pass in order to later in their schooling get high school eligibility. The school has a statutory mandate to provide all students with opportunities to achieve acceptable knowledge requirements and if this is not done, a special support should be deployed and documented in an education plan. Education plans must constantly endure a lot of criticism because they do often lack in quality.

    Through a qualitative text analysis 15 education plans will be reviewed for the purpose of developing knowledge about how the work with special support in math are projected and processed. The study shows that there is a link between education plan and knowledge requirement in 22 of the 29 necessary descriptions in 11 of the 15 education plans. In four of the 15 education plans a description of the student's special needs based on the Mathematical Syllabuses core content and given abilities is missing entirely. Of the 38 measures in the education plans there are six with distinct character and the remaining 32 are of a diffuse character. A clear majority of the measures do not fulfill the criteria of evaluability and concreteness specified in Skolverkets general advice. The study shows that 26 of the 38 measures are related to current research on what is considered to be favorable measures for students in mathematics difficulties. Only two of the 15 education plans shows a clear connection between the students written needs and measures.

  • 107.
    Andersson, Pierre
    et al.
    Örebro University, School of Science and Technology.
    Norlander, Arvid
    Örebro University, School of Science and Technology.
    Indoor Positioning Using WLAN2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report evaluates various methods that can be used to position a smartphone running the Android platform, without the use of any special hardware or infrastructure and in conditions where GPS is unavailable or unreliable; such as indoors. Furthermore, it covers the implementation of such a system with the use of a deterministic fingerprinting method that is reasonably device independent, a method which involves measuring a series of reference points, called fingerprints, in an area and using those to locate the user.

    The project was carried on behalf of Sigma, a Swedish software consulting company.

  • 108.
    Andersson, Robin
    et al.
    Örebro University, School of Science and Technology.
    Franzén, Simon
    Örebro University, School of Science and Technology.
    Realtidsuppdaterad dashboard2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report will be covering the creation of the Realtime-Updated Dashboard, made for Flex Applications. The Dashboard, which could be seen as an interactive pinboard, is a new product which will be implemented in Flex Applications existing system for employee administration.

    A deep-dive into the subject of information overload was also made during thedevelopment of the application. This was later used to question the design choices made. The results of this showed that there is no one correct way of designing an interface, but rather guidelines to help in certain situations.

    The application was written in the TypeScript language together with the framework Angular 2. The application was at first developed as a stand-alone project as there was no need for it to be integrated into the existing system from the start. This also gave a more relaxed environment while learning TypeScript and Angular2.

    The application was later integrated with the existing system. This integration was seen as a success as the handling of the data from the database worked as expected.

  • 109.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Adolfsson, Daniel
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Magnusson, Martin
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Incorporating Ego-motion Uncertainty Estimates in Range Data Registration2017In: 2017 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 1389-1395Conference paper (Refereed)
    Abstract [en]

    Local scan registration approaches commonlyonly utilize ego-motion estimates (e.g. odometry) as aninitial pose guess in an iterative alignment procedure. Thispaper describes a new method to incorporate ego-motionestimates, including uncertainty, into the objective function of aregistration algorithm. The proposed approach is particularlysuited for feature-poor and self-similar environments,which typically present challenges to current state of theart registration algorithms. Experimental evaluation showssignificant improvements in accuracy when using data acquiredby Automatic Guided Vehicles (AGVs) in industrial productionand warehouse environments.

  • 110.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Bouguerra, Abdelbaki
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar Nikolaev
    nria Grenoble Rhône-Alpes, Meylan-Montbonnot, France .
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saarinen, Jari Pekka
    Örebro University, School of Science and Technology. Aalto University, Espo, Finland .
    Sherikov, Aleksander
    Centre de recherche Grenoble Rhône-Alpes, Grenoble, France .
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Autonomous transport vehicles: where we are and what is missing2015In: IEEE robotics & automation magazine, ISSN 1070-9932, E-ISSN 1558-223X, Vol. 22, no 1, p. 64-75Article in journal (Refereed)
    Abstract [en]

    In this article, we address the problem of realizing a complete efficient system for automated management of fleets of autonomous ground vehicles in industrial sites. We elicit from current industrial practice and the scientific state of the art the key challenges related to autonomous transport vehicles in industrial environments and relate them to enabling techniques in perception, task allocation, motion planning, coordination, collision prediction, and control. We propose a modular approach based on least commitment, which integrates all modules through a uniform constraint-based paradigm. We describe an instantiation of this system and present a summary of the results, showing evidence of increased flexibility at the control level to adapt to contingencies.

  • 111.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Bouguerra, Abdelbaki
    Örebro University, School of Science and Technology.
    Åstrand, Björn
    CAISR Centrum för tillämpade intelligenta system (IS-lab), Högskolan i Halmstad, Halmstad, Sweden.
    Rögnvaldsson, Thorsteinn
    CAISR Centrum för tillämpade intelligenta system (IS-lab), Högskolan i Halmstad, Halmstad, Sweden.
    Gold-Fish SLAM: An Application of SLAM to Localize AGVs2014In: Field and Service Robotics: Results of the 8th International Conference / [ed] Yoshida, Kazuya; Tadokoro, Satoshi, Heidelberg, Germany: Springer Berlin/Heidelberg, 2014, p. 585-598Chapter in book (Refereed)
    Abstract [en]

    The main focus of this paper is to present a case study of a SLAM solution for Automated Guided Vehicles (AGVs) operating in real-world industrial environments. The studied solution, called Gold-fish SLAM, was implemented to provide localization estimates in dynamic industrial environments, where there are static landmarks that are only rarely perceived by the AGVs. The main idea of Gold-fish SLAM is to consider the goods that enter and leave the environment as temporary landmarks that can be used in combination with the rarely seen static landmarks to compute online estimates of AGV poses. The solution is tested and verified in a factory of paper using an eight ton diesel-truck retrofitted with an AGV control system running at speeds up to 3 m/s. The paper includes also a general discussion on how SLAM can be used in industrial applications with AGVs

  • 112.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Saarinen, Jari
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Drive the Drive: From Discrete Motion Plans to Smooth Drivable Trajectories2014In: Robotics, E-ISSN 2218-6581, Vol. 3, no 4, p. 400-416Article in journal (Refereed)
    Abstract [en]

    Autonomous navigation in real-world industrial environments is a challenging task in many respects. One of the key open challenges is fast planning and execution of trajectories to reach arbitrary target positions and orientations with high accuracy and precision, while taking into account non-holonomic vehicle constraints. In recent years, lattice-based motion planners have been successfully used to generate kinematically and kinodynamically feasible motions for non-holonomic vehicles. However, the discretized nature of these algorithms induces discontinuities in both state and control space of the obtained trajectories, resulting in a mismatch between the achieved and the target end pose of the vehicle. As endpose accuracy is critical for the successful loading and unloading of cargo in typical industrial applications, automatically planned paths have not been widely adopted in commercial AGV systems. The main contribution of this paper is a path smoothing approach, which builds on the output of a lattice-based motion planner to generate smooth drivable trajectories for non-holonomic industrial vehicles. The proposed approach is evaluated in several industrially relevant scenarios and found to be both fast (less than 2 s per vehicle trajectory) and accurate (end-point pose errors below 0.01 m in translation and 0.005 radians in orientation).

  • 113.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Saarinen, Jari
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology. SCANIA AB, Södertälje, Sweden.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Fast, continuous state path smoothing to improve navigation accuracy2015In: IEEE International Conference on Robotics and Automation (ICRA), 2015, IEEE Computer Society, 2015, p. 662-669Conference paper (Refereed)
    Abstract [en]

    Autonomous navigation in real-world industrial environments is a challenging task in many respects. One of the key open challenges is fast planning and execution of trajectories to reach arbitrary target positions and orientations with high accuracy and precision, while taking into account non-holonomic vehicle constraints. In recent years, lattice-based motion planners have been successfully used to generate kinematically and kinodynamically feasible motions for non-holonomic vehicles. However, the discretized nature of these algorithms induces discontinuities in both state and control space of the obtained trajectories, resulting in a mismatch between the achieved and the target end pose of the vehicle. As endpose accuracy is critical for the successful loading and unloading of cargo in typical industrial applications, automatically planned paths have not be widely adopted in commercial AGV systems. The main contribution of this paper addresses this shortcoming by introducing a path smoothing approach, which builds on the output of a lattice-based motion planner to generate smooth drivable trajectories for non-holonomic industrial vehicles. In real world tests presented in this paper we demonstrate that the proposed approach is fast enough for online use (it computes trajectories faster than they can be driven) and highly accurate. In 100 repetitions we achieve mean end-point pose errors below 0.01 meters in translation and 0.002 radians in orientation. Even the maximum errors are very small: only 0.02 meters in translation and 0.008 radians in orientation.

  • 114.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Real time registration of RGB-D data using local visual features and 3D-NDT registration2012In: Proc. of International Conference on Robotics and Automation (ICRA) Workshop on Semantic Perception, Mapping and Exploration (SPME), IEEE, 2012Conference paper (Refereed)
    Abstract [en]

    Recent increased popularity of RGB-D capable sensors in robotics has resulted in a surge of related RGBD registration methods. This paper presents several RGB-D registration algorithms based on combinations between local visual feature and geometric registration. Fast and accurate transformation refinement is obtained by using a recently proposed geometric registration algorithm, based on the Three-Dimensional Normal Distributions Transform (3D-NDT). Results obtained on standard data sets have demonstrated mean translational errors on the order of 1 cm and rotational errors bellow 1 degree, at frame processing rates of about 15 Hz.

  • 115.
    Andrén, Daniel
    et al.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Shao, Lei
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Länk, Nils Odebo
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Acimovic, Srdjan S.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Johansson, Peter
    Örebro University, School of Science and Technology. Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Käll, Mikael
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Probing Photothermal Effects on Optically Trapped Gold Nanorods by Simultaneous Plasmon Spectroscopy and Brownian Dynamics Analysis2017In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 11, no 10, p. 10053-10061Article in journal (Refereed)
    Abstract [en]

    Plasmonic gold nanorods are prime candidates for a variety of biomedical, spectroscopy, data storage, and sensing applications. It was recently shown that gold nanorods optically trapped by a focused circularly polarized laser beam can function as extremely efficient nanoscopic rotary motors. The system holds promise for-applications ranging from nanofluidic flow control and nanorobotics to biomolecular actuation and analysis. However, to fully exploit this potential, one needs to be able to control and understand heating effects associated with laser trapping. We investigated photothermal heating of individual rotating gold nanorods by simultaneously probing their localized surface plasmon resonance spectrum and rotational Brownian dynamics over extended periods of time. The data reveal an extremely slow nanoparticle reshaping process, involving migration of the order of a few hundred atoms per minute, for moderate laser powers and a trapping wavelength close to plasmon resonance. The plasmon spectroscopy and Brownian analysis allows for separate temperature estimates based on the refractive index and the viscosity of the water surrounding a trapped nanorod. We show that both measurements yield similar effective temperatures, which correspond to the actual temperature at a distance of the order 10-15 nm from the particle surface. Our results shed light on photothermal processes on the nanoscale and will be useful in evaluating the applicability and performance of nanorod motors and optically heated nanoparticles for a variety of applications.

  • 116.
    ANGELONE, MARIA LAURA
    Örebro University, School of Science and Technology.
    AndroidOS- Robot Command Interface2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 117.
    Angelstam, Per
    et al.
    Örebro University, School of Science and Technology.
    Andersson, Kjell
    Isacson, Maths
    Gavrilov, Dmitri V.
    Axelsson, Robert
    Bäckström, Mattias
    Örebro University, School of Science and Technology.
    Degerman, Erik
    Elbakidze, Marine
    Kazakova-Apkarimova, Elena Yu.
    Sartz, Lotta
    Örebro University, School of Science and Technology.
    Sadbom, Stefan
    Törnblom, Johan
    Örebro University, School of Science and Technology.
    Learning about the history of landscape use for the future: consequences for ecological and social systems in Swedish Bergslagen2013In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 42, no 2, p. 146-159Article in journal (Refereed)
    Abstract [en]

    Barriers and bridges to implement policies about sustainable development and sustainability commonly depend on the past development of social-ecological systems. Production of metals required integration of use of ore, streams for energy, and wood for bioenergy and construction, as well as of multiple societal actors. Focusing on the Swedish Bergslagen region as a case study we (1) describe the phases of natural resource use triggered by metallurgy, (2) the location and spatial extent of 22 definitions of Bergslagen divided into four zones as a proxy of cumulative pressure on landscapes, and (3) analyze the consequences for natural capital and society. We found clear gradients in industrial activity, stream alteration, and amount of natural forest from the core to the periphery of Bergslagen. Additionally, the legacy of top-down governance is linked to today's poorly diversified business sector and thus municipal vulnerability. Comparing the Bergslagen case study with other similar regions in Russia and Germany, we discuss the usefulness of multiple case studies.

  • 118.
    Angergård, Ida
    Örebro University, School of Science and Technology.
    Ungdomars val av mat relaterat till deras uppfattning om hälsa och miljö2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Food, environment and human health is one consistent theme for this essay that aims to show on the positive opportunities whit educating young people in the environmental impacts of personal foodchoice. Personal choice of food makes a difference to the environment but those environmental friendly choices can also have a positive effect on the health of the individual. Some of the reasons why certain food is preferred before others is brought up in the background. Interviews have been done with four adolescents in the age group 13-15 years studying in two different schools. The results show that the adolescents in this study would like to eat food that is good for the environment but generally miss information about what food that is.

  • 119.
    Antegård, Kristian
    et al.
    Örebro University, School of Science and Technology.
    Mucic, Fuad
    Örebro University, School of Science and Technology.
    CE-märkning av lyftredskap. Processen, användningsområden och dokumentation.2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report is a thesis carried out at BAE Systems Bofors AB in Karlskoga. This report is about exploring and to give suggestions for improvement of the production process and CE-marking of lifting tools. The report also discusses documentation management and documentation requirements for CE marking. What is true at the CE Marking of lifting tools designed for military purposes. The report provides a basic understanding of what purposes CE-marking has and why it is done. Through research and interviews conducted at the company a map of the process for creating and CE marking of lifting tools was created. Using the same method an investigation of the dossier was done. After an analysis of the problem and what emerged during the interviews, the results of the current situation were summarized. One proposed solution was developed that contains suggestions for improvement of the process, suggestions for documentation that should be available and suggestions where documentation should be stored.

  • 120.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology. Scania AB, Södertälje, Sweden.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    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.
    Efficient Measurement Planning for Remote Gas Sensing with Mobile Robots2015In: 2015 IEEE International Conference on Robotics and Automation (ICRA), Washington, USA: IEEE Computer Society, 2015, p. 3428-3434Conference paper (Refereed)
    Abstract [en]

    The problem of gas detection is relevant to manyreal-world applications, such as leak detection in industrialsettings and surveillance. In this paper we address the problemof gas detection in large areas with a mobile robotic platformequipped with a remote gas sensor. We propose a novelmethod based on convex relaxation for quickly finding anexploration plan that guarantees a complete coverage of theenvironment. Our method proves to be highly efficient in termsof computational requirements and to provide nearly-optimalsolutions. We validate our approach both in simulation andin real environments, thus demonstrating its applicability toreal-world problems.

  • 121.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Fan, Han
    Örebro University, School of Science and Technology.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Improving Gas Tomography With Mobile Robots: An Evaluation of Sensing Geometries in Complex Environments2017In: 2017 ISOCS/IEEE International Symposium on Olfaction andElectronic Nose (ISOEN 2017) Proceedings, 2017, article id 7968895Conference paper (Refereed)
    Abstract [en]

    An accurate model of gas emissions is of high importance in several real-world applications related to monitoring and surveillance. Gas tomography is a non-intrusive optical method to estimate the spatial distribution of gas concentrations using remote sensors. The choice of sensing geometry, which is the arrangement of sensing positions to perform gas tomography, directly affects the reconstruction quality of the obtained gas distribution maps. In this paper, we present an investigation of criteria that allow to determine suitable sensing geometries for gas tomography. We consider an actuated remote gas sensor installed on a mobile robot, and evaluated a large number of sensing configurations. Experiments in complex settings were conducted using a state-of-the-art CFD-based filament gas dispersal simulator. Our quantitative comparison yields preferred sensing geometries for sensor planning, which allows to better reconstruct gas distributions.

  • 122.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Havoutis, Ioannis
    Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy.
    Semini, Claudio
    Department of Advanced Robotics,Istituto Italiano di Tecnologia, Genova, Italy.
    Buchli, Jonas
    Eidgenössische Technische Hochschule Zürich (ETH), Zurich, Schweiz.
    Caldwell, Darwin G.
    Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy.
    A comparison of search-based planners for a legged robot2013Conference paper (Refereed)
    Abstract [en]

    Path planning for multi-DoF legged robots is achallenging task due to the high dimensionality and complexityof the planning space. We present our first attempt to builda path planning framework for the hydraulic quadruped -HyQ. Our approach adopts a similar strategy to [1], whereplanning is divided into a task-space and a joint-space part.The task-space planner finds a path for the center of gravity(COG) of the robot, while then the footstep planner generates theappropriate footholds under reachability and stability criteria.Next the joint-space planner translates the task-space COGtrajectories into robot joint angles. We present a comparisonof a set of search-based planning algorithms; Dijkstra, A* andARA*, and evaluate these over a set of given terrains and anumber of varying start and end points. All test runs supportthat our approach is a simple yet robust solution. We reportcomparisons in path length, computation time, and path cost,between the aforementioned planning algorithms.

  • 123.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    The Right Direction to Smell: Efficient Sensor Planning Strategies for Robot Assisted Gas Tomography2016In: 2016 IEEE International Conference on Robotics and Automation (ICRA), New York, USA: IEEE Robotics and Automation Society, 2016, p. 4275-4281Conference paper (Refereed)
    Abstract [en]

    Creating an accurate model of gas emissions is an important task in monitoring and surveillance applications. A promising solution for a range of real-world applications are gas-sensitive mobile robots with spectroscopy-based remote sensors that are used to create a tomographic reconstruction of the gas distribution. The quality of these reconstructions depends crucially on the chosen sensing geometry. In this paper we address the problem of sensor planning by investigating sensing geometries that minimize reconstruction errors, and then formulate an optimization algorithm that chooses sensing configurations accordingly. The algorithm decouples sensor planning for single high concentration regions (hotspots) and subsequently fuses the individual solutions to a global solution consisting of sensing poses and the shortest path between them. The proposed algorithm compares favorably to a template matching technique in a simple simulation and in a real-world experiment. In the latter, we also compare the proposed sensor planning strategy to the sensing strategy of a human expert and find indications that the quality of the reconstructed map is higher with the proposed algorithm.

  • 124.
    Arain, Muhammad Asif
    et al.
    Örebro University, School of Science and Technology.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Global coverage measurement planning strategies for mobile robots equipped with a remote gas sensor2015In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, no 3, p. 6845-6871Article in journal (Refereed)
    Abstract [en]

    The problem of gas detection is relevant to many real-world applications, such as leak detection in industrial settings and landfill monitoring. In this paper, we address the problem of gas detection in large areas with a mobile robotic platform equipped with a remote gas sensor. We propose an algorithm that leverages a novel method based on convex relaxation for quickly solving sensor placement problems, and for generating an efficient exploration plan for the robot. To demonstrate the applicability of our method to real-world environments, we performed a large number of experimental trials, both on randomly generated maps and on the map of a real environment. Our approach proves to be highly efficient in terms of computational requirements and to provide nearly-optimal solutions.

  • 125.
    Argyriou, Marios
    et al.
    DTU Compute, Technical University of Denmark, Lyngby, Denmark.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark, Lyngby, Denmark.
    Spognardi, Angelo
    DTU Compute, Technical University of Denmark, Lyngby, Denmark; Dipartimento Informatica, Sapienza Università di Roma, Rome, Italy.
    Security Flows in OAuth 2.0 Framework: A Case Study2017In: Computer safety, reliability, and security: SAFECOMP 2017 Workshops, ASSURE, DECSoS, SASSUR, TELERISE, and TIPS, Trento, Italy, September 12, 2017, Proceedings / [ed] Tonetta S., Schoitsch E., Bitsch F., Springer, 2017, Vol. 10489, p. 396-406Conference paper (Refereed)
    Abstract [en]

    The burst in smartphone use, handy design in laptops and tablets as well as other smart products, like cars with the ability to drive you around, manifests the exponential growth of network usage and the demand of accessing remote data on a large variety of services. However, users notoriously struggle to maintain distinct accounts for every single service that they use. The solution to this problem is the use of a Single Sign On (SSO) framework, with a unified single account to authenticate user’s identity throughout the different services. In April 2007, AOL introduced OpenAuth framework. After several revisions and despite its wide adoption, OpenAuth 2.0 has still several flaws that need to be fixed in several implementations. In this paper, we present a thorough review about both benefits of this single token authentication mechanism and its open flaws.

  • 126.
    Arnesson, Robin
    Örebro University, School of Science and Technology.
    POS-terminal XGD K3702013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis comprises the implementation of the basic functionality in a POS-terminal (Point OfSale) and the design of a client-server system in which the terminal acts as a client. The thesis wasdeveloped as an assignment from IBSP Labs AB where the goal was to create a system for wirelesspayments using POS-terminal XGD K370. The assignment was mainly comprised of thedevelopment of two programs; the application in the terminal which serves as an interface to thecustomer, and the back end program that processes incoming transactions from the terminal. Thisthesis presents the implementation of these programs and depicts the theory associated with themethods and tools used in the implementation.

  • 127.
    Arvidsson, Mattias
    Örebro University, School of Science and Technology.
    Introduktion till Markovkedjor2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 128.
    Asaad Sharif Elemara, Hadil
    Örebro University, School of Science and Technology.
    GRUNDLÄGGNINGSMETODER-VAL AV GRUNDLÄGGNINGSMETOD FÖR SMÅHUS I ÖREBRO LÄN2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Foundations support entire houses and are required to be adequately well-built to carry a building’s

    mass for many years without facing problems due to environmental impacts such as moisture and

    frost. This work covers three basic types of foundations; concrete slab, crawl space and block

    foundation. The aim of this work is to investigate the construction methods of the foundations

    mentioned above, which are used within the construction of single-family homes in the city of

    Örebro, Sweden. Additionally, the basis of selection of these foundations by various construction

    companies in respect to risk of moisture-related problems is examined.

    Information about the foundations is collected from scholarly literature as well as qualitative

    interviews with seven construction companies’ experts. Ultimately, this study found that concrete

    slab with underlying insulation is more commonly used within the construction of single-family

    homes in Örebro than the other alternatives. Operators find that this foundation has many

    advantages in comparison with the other foundation techniques.

  • 129.
    Asadi, Sahar
    Örebro University, School of Science and Technology.
    Towards Dense Air Quality Monitoring: Time-Dependent Statistical Gas Distribution Modelling and Sensor Planning2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis addresses the problem of gas distribution modelling for gas monitoring and gas detection. The presented research is particularly focused on the methods that are suitable for uncontrolled environments. In such environments, gas source locations and the physical properties of the environment, such as humidity and temperature may be unknown or only sparse noisy local measurements are available. Example applications include air pollution monitoring, leakage detection, and search and rescue operations.

    This thesis addresses how to efficiently obtain and compute predictive models that accurately represent spatio-temporal gas distribution.

    Most statistical gas distribution modelling methods assume that gas dispersion can be modelled as a time-constant random process. While this assumption may hold in some situations, it is necessary to model variations over time in order to enable applications of gas distribution modelling for a wider range of realistic scenarios.

    This thesis proposes two time-dependent gas distribution modelling methods. In the first method, a temporal (sub-)sampling strategy is introduced. In the second method, a time-dependent gas distribution modelling approach is presented, which introduces a recency weight that relates measurement to prediction time. These contributions are presented and evaluated as an extension of a previously proposed method called Kernel DM+V using several simulation and real-world experiments. The results of comparing the proposed time-dependent gas distribution modelling approaches to the time-independent version Kernel DM+V indicate a consistent improvement in the prediction of unseen measurements, particularly in dynamic scenarios under the condition that there is a sufficient spatial coverage. Dynamic scenarios are often defined as environments where strong fluctuations and gas plume development are present.

    For mobile robot olfaction, we are interested in sampling strategies that provide accurate gas distribution models given a small number of samples in a limited time span. Correspondingly, this thesis addresses the problem of selecting the most informative locations to acquire the next samples.

    As a further contribution, this thesis proposes a novel adaptive sensor planning method. This method is based on a modified artificial potential field, which selects the next sampling location based on the currently predicted gas distribution and the spatial distribution of previously collected samples. In particular, three objectives are used that direct the sensor towards areas of (1) high predictive mean and (2) high predictive variance, while (3) maximising the coverage area. The relative weight of these objectives corresponds to a trade-off between exploration and exploitation in the sampling strategy. This thesis discusses the weights or importance factors and evaluates the performance of the proposed sampling strategy. The results of the simulation experiments indicate an improved quality of the gas distribution models when using the proposed sensor planning method compared to commonly used methods, such as random sampling and sampling along a predefined sweeping trajectory. In this thesis, we show that applying a locality constraint on the proposed sampling method decreases the travelling distance, which makes the proposed sensor planning approach suitable for real-world applications where limited resources and time are available. As a real-world use-case, we applied the proposed sensor planning approach on a micro-drone in outdoor experiments.

    Finally, this thesis discusses the potential of using gas distribution modelling and sensor planning in large-scale outdoor real-world applications. We integrated the proposed methods in a framework for decision-making in hazardous inncidents where gas leakage is involved and applied the gas distribution modelling in two real-world use-cases. Our investigation indicates that the proposed sensor planning and gas distribution modelling approaches can be used to inform experts both about the gas plume and the distribution of gas in order to improve the assessment of an incident.

  • 130.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Badica, Costin
    University of Craiova, Craiova, Romania.
    Comes, Tina
    Karslruhe Institute of Technology, Karslruhe, Germany.
    Conrado, Claudine
    Thales Research and Technology, Delft, The Nederlands.
    Evers, Vanessa
    University of Amsterdam, Amsterdam, The Netherlands.
    Groen, Frans
    University of Amsterdam, Amsterdam, The Netherlands.
    Illie, Sorin
    University of Craiova, Craiova, Romania.
    Steen Jensen, Jan
    Danish Emergency Management Agency (DEMA), Birkerød, Denmark.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Milan, Bianca
    DCMR, Delft, The Netherlands.
    Neidhart, Thomas
    Space Applications Services, Zaventem, Belgium.
    Nieuwenhuis, Kees
    Thales Research and Technology, Delft, The Netherlands.
    Pashami, Sepideh
    Örebro University, School of Science and Technology.
    Pavlin, Gregor
    Thales Research and Technology, Delft, The Netherlands.
    Pehrsson, Jan
    Prolog Development Center, Brøndby Copenhagen, Denmark.
    Pinchuk, Rani
    Space Applications and Services, Zaventem, Belgium.
    Scafes, Mihnea
    University of Craiova, Craiova, Romania.
    Schou-Jensen, Leo
    DCMR, Brøndby Copenhagen, Denmark.
    Schultmann, Frank
    Karslruhe Institute of Technology, Karlsruhe, Germany.
    Wijngaards, Niek
    Thales Research and Technology, Delft, the Netherlands.
    ICT solutions supporting collaborative information acquisition, situation assessment and decision making in contemporary environmental management problems: the DIADEM approach2011In: Proceedings of the 25th EnviroInfo Conference "Environmental Informatics", Herzogenrath: Shaker Verlag, 2011, p. 920-931Conference paper (Refereed)
    Abstract [en]

    This paper presents a framework of ICT solutions developed in the EU research project DIADEM that supports environmental management with an enhanced capacity to assess population exposure and health risks, to alert relevant groups and to organize efficient response. The emphasis is on advanced solutions which are economically feasible and maximally exploit the existing communication, computing and sensing resources. This approach enables efficient situation assessment in complex environmental management problems by exploiting relevant information obtained from citizens via the standard communication infrastructure as well as heterogeneous data acquired through dedicated sensing systems. This is achieved through a combination of (i) advanced approaches to gas detection and gas distribution modelling, (ii) a novel service-oriented approach supporting seamless integration of human-based and automated reasoning processes in large-scale collaborative sense making processes and (iii) solutions combining Multi-Criteria Decision Analysis, Scenario-Based Reasoning and advanced human-machine interfaces. This paper presents the basic principles of the DIADEM solutions, explains how different techniques are combined to a coherent decision support system and briefly discusses evaluation principles and activities in the DIADEM project.

  • 131.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Fan, Han
    Örebro University, School of Science and Technology.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Time-dependent gas distribution modelling2017In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 96, p. 157-170Article in journal (Refereed)
    Abstract [en]

    Artificial olfaction can help to address pressing environmental problems due to unwanted gas emissions. Sensor networks and mobile robots equipped with gas sensors can be used for e.g. air pollution monitoring. Key in this context is the ability to derive truthful models of gas distribution from a set of sparse measurements. Most statistical gas distribution modelling methods assume that gas dispersion is a time constant random process. While this assumption approximately holds in some situations, it is necessary to model variations over time in order to enable applications of gas distribution modelling in a wider range of realistic scenarios. Time-invariant approaches cannot model well evolving gas plumes, for example, or major changes in gas dispersion due to a sudden change of the environmental conditions. This paper presents two approaches to gas distribution modelling, which introduce a time-dependency and a relation to a time-scale in generating the gas distribution model either by sub-sampling or by introducing a recency weight that relates measurement and prediction time. We evaluated these approaches in experiments performed in two real environments as well as on several simulated experiments. As expected, the comparison of different sub-sampling strategies revealed that more recent measurements are more informative to derive an estimate of the current gas distribution as long as a sufficient spatial coverage is given. Next, we compared a time-dependent gas distribution modelling approach (TD Kernel DM+V), which includes a recency weight, to the state-of-the-art gas distribution modelling approach (Kernel DM+V), which does not consider sampling times. The results indicate a consistent improvement in the prediction of unseen measurements, particularly in dynamic scenarios. Furthermore, this paper discusses the impact of meta-parameters in model selection and compares the performance of time-dependent GDM in different plume conditions. Finally, we investigated how to set the target time for which the model is created. The results indicate that TD Kernel DM+V performs best when the target time is set to the maximum sampling time in the test set.

  • 132.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Approaches to Time-Dependent Gas Distribution Modelling2015In: 2015 European Conference on Mobile Robots (ECMR), New York: IEEE conference proceedings , 2015, article id 7324215Conference paper (Refereed)
    Abstract [en]

    Mobile robot olfaction solutions for gas distribution modelling offer a number of advantages, among them autonomous monitoring in different environments, mobility to select sampling locations, and ability to cooperate with other systems. However, most data-driven, statistical gas distribution modelling approaches assume that the gas distribution is generated by a time-invariant random process. Such time-invariant approaches cannot model well developing plumes or fundamental changes in the gas distribution. In this paper, we discuss approaches that explicitly consider the measurement time, either by sub-sampling according to a given time-scale or by introducing a recency weight that relates measurement and prediction time. We evaluate the performance of these time-dependent approaches in simulation and in real-world experiments using mobile robots. The results demonstrate that in dynamic scenarios improved gas distribution models can be obtained with time-dependent approaches.

  • 133.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Reggente, Matteo
    Örebro University, School of Science and Technology.
    Stachniss, Cyrill
    University of Freiburg, Freiburg, Germany.
    Plagemann, Christian
    Stanford University, Stanford CA, USA.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Statistical gas distribution modeling using kernel methods2011In: Intelligent systems for machine olfaction: tools and methodologies / [ed] E. L. Hines and M. S. Leeson, IGI Global, 2011, 1, p. 153-179Chapter in book (Refereed)
    Abstract [en]

    Gas distribution models can provide comprehensive information about a large number of gas concentration measurements, highlighting, for example, areas of unusual gas accumulation. They can also help to locate gas sources and to plan where future measurements should be carried out. Current physical modeling methods, however, are computationally expensive and not applicable for real world scenarios with real-time and high resolution demands. This chapter reviews kernel methodsthat statistically model gas distribution. Gas measurements are treated as randomvariables, and the gas distribution is predicted at unseen locations either using akernel density estimation or a kernel regression approach. The resulting statistical 

    apmodelsdo not make strong assumptions about the functional form of the gas distribution,such as the number or locations of gas sources, for example. The majorfocus of this chapter is on two-dimensional models that provide estimates for themeans and predictive variances of the distribution. Furthermore, three extensionsto the presented kernel density estimation algorithm are described, which allow toinclude wind information, to extend the model to three dimensions, and to reflecttime-dependent changes of the random process that generates the gas distributionmeasurements. All methods are discussed based on experimental validation usingreal sensor data.

  • 134.
    Ashhami, Arnavaz
    Örebro University, School of Science and Technology.
    Assessment of Extractable Organic Fluorine (EOF) Content and Contribution of Per- and Polyfluoroalkyl Substances (PFASs) in Cosmetic Products2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFASs) are a large group of compounds consisting of a fully or partially fluorinated alkyl chain and a functional head group. The structure of PFASs yields molecules that are highly desired in both industrial and commercial applications were properties such as oil and water repellency are needed. However PFASs have also been linked to health problems such as cancer, hepatoxicity and reproductive toxicity. Recently the analysis of total organic fluorine (TOF) and PFASs in several matrices have revealed the presence of unidentified organofluorine (OF) compounds. In addition fluorinated compounds have been identified in various personal care products (PCPs).

    The aim of this study was to quantify the extractable organic fluorine (EOF) content and contribution of individual PFASs in various cosmetic products in order to determine the amount of unidentified OF and asses the possibility of a risk to human health. Determination of EOF was conducted using combustion ion chromatography (CIC) and followed up through target analysis by liquid chromatography tandem-mass spectrometry (LC-MS/MS).

    Fluorinated compounds were detected in 21 of the 32 analyzed samples in concentrations ranging up to 242 μg/g. Target analysis established polyfluoroalkyl phosphate esters (PAPs) as the main contributing compounds to total PFASs, followed by perfluoroalkyl carboxylic acids (PFCAs). In addition perfluoroalkyl sulfonic acids (PFSAs) and fluorotelomer sulfonic acids (FTSAs) were detected. Unidentified OF ranged from 53-100% in a majority of the samples. In addition the study was able to confirm the presence of fluorinated compounds other than those declared on the product labels.

    The results suggest cosmetic products as a possible contributing source to total PFAS exposure, making their presence a possible concern to human health. Further studies are required to assess the risk.

  • 135.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Printing / Additative Manufacturing from Product Creator and Tool Maker Perspectives in the Automotive Industry2016Conference paper (Other academic)
  • 136.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Improved Lightweight Manufacturing Flexibility by Stamping of Selectively Laser Heat Treated Boron Steel Sheet2016Conference paper (Other academic)
  • 137.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Innovative Lead Time and Cost Efficient Tools and Dies for Lightweight Autobody Components2016Conference paper (Other academic)
  • 138.
    Asnafi, Nader
    et al.
    Örebro University, School of Science and Technology.
    Andersson, Roger
    Persson, Martin
    Liljengren, Magnus
    Comparison of Lightweight Solutions: Low Cost Production Process for High Strength Boron Steel Components2016Conference paper (Other academic)
  • 139.
    Asnake, Solomon
    Örebro University, School of Science and Technology.
    Interaction of brominated flame retardants with the chicken and zebrafish androgen receptors2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The survival of organisms depends on their ability to use different signaling pathways to adapt to the environment. The endocrine system consists of glands that release hormones to the blood stream. Male reproductive functions are regulated by androgens through interactions with the androgen receptor (AR). AR has been characterized in chicken and zebrafish where they use testosterone and 11-ketotestosterone as their primary androgens, respectively. AR function has been disturbed by different endocrine disrupting compounds (EDCs) present in the environment causing detrimental effects on avian and fish species. Brominated flame retardants (BFRs) are a group of EDCs that are ubiquitous in the environment. Molecular modeling techniques using computer simulations such as docking and molecular dynamics are a useful tool in the identification of EDCs. The capacity to test thousands of compounds at once has helped in the early identification of EDCs that interact with AR. Two groups of BFRs, the 1,2-dibromo-4- cyclohexane diastereomers (TBECH) and the compounds synthesized from 2, 4, 6-tribromophenol, allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6- tribromophenyl ether (BATE) and 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE) interact and alter AR activity in human in vitro studies. As models for avian and fish species, chicken and zebrafish were used to test these BFRs. TBECH diastereomers were able to bind to the AR, estrogen receptors and thyroid receptors in the chicken and to the AR in zebrafish. ATE, BATE and DPTE were also able to interact with the chicken AR and zebrafish AR. Activation studies using cell lines showed that TBECH diastereomers acted as agonists to the cAR and zAR while ATE, BATE and DPTE acted as antagonists. The BFRs also altered multiple signaling pathways such as the apoptotic, antiapoptotic, immune, drug metabolizing and DNA methylation systems and in vivo studies resulted in physiological effects on zebrafish.

    List of papers
    1. 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH)-mediated steroid hormone receptor activation and gene regulation in chicken LMH cells
    Open this publication in new window or tab >>1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH)-mediated steroid hormone receptor activation and gene regulation in chicken LMH cells
    Show others...
    2014 (English)In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 33, no 4, p. 891-899Article in journal (Refereed) Published
    Abstract [en]

    The incorporation of brominated flame retardants into industrial and household appliances has increased their occurrence in the environment, resulting in deleterious effects on wildlife. With the increasing restraints on available compounds, there has been a shift to using brominated flame retardants that has seen the production of alternative brominated flame retardants such as 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH), which has been detected in the environment. In previous in silico and in vitro studies the authors have shown that TBECH can activate both the human androgen receptor (hAR) and the zebrafish AR (zAR) suggesting that it is a potential endocrine disruptor. The present study was aimed at determining the interaction of TBECH with the chicken AR (cAR). In the present study, TBECH bound to cAR, but in vitro activation assay studies using the chicken LMH cell line showed it had a potency of only 15% compared with testosterone. Sequence difference between ARs from different species may contribute to the different responses to TBECH. Further quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) analysis showed that TBECH interacted with and altered the expression of both thyroid receptors and estrogen receptors. In addition, the qRT-PCR analysis showed that TBECH altered the transcription pattern of genes involved in inflammatory, apoptotic, proliferative, DNA methylation, and drug-metabolizing pathways. This demonstrates that TBECH, apart from activating cAR, can also influence multiple biological pathways in the chicken.

    Place, publisher, year, edition, pages
    Hoboken: Wiley-Blackwell, 2014
    Keywords
    Endocrine disruptor, Diastereomer, Enantiomer, Quantitative polymerase chain reaction (qPCR), Gene regulation
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science; Biology
    Identifiers
    urn:nbn:se:oru:diva-34941 (URN)10.1002/etc.2509 (DOI)000333538700020 ()2-s2.0-84897431931 (Scopus ID)
    Funder
    Swedish Research Council
    Note

    Funding Agency:

    Örebro University

    Available from: 2014-05-05 Created: 2014-05-05 Last updated: 2017-12-05Bibliographically approved
    2. The brominated flame retardant TBECH activates the zebrafish (Danio rerio) androgen receptor, alters gene transcription and causes developmental disturbances
    Open this publication in new window or tab >>The brominated flame retardant TBECH activates the zebrafish (Danio rerio) androgen receptor, alters gene transcription and causes developmental disturbances
    2013 (English)In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 142, p. 63-72Article in journal (Refereed) Published
    Abstract [en]

    Tetrabromoethylcyclohexane (TBECH) is a brominated flame retardant that has been shown to be a potent agonist to the human androgen receptor (AR). However, while it is present in the environment, it is not known if it interacts with AR from aquatic species. The present study was therefore aimed at improving our understanding of how TBECH affects aquatic animals using zebrafish as a model organism. In silica modeling demonstrated that TBECH diastereomers bind to the zebrafish androgen receptor (zAR) and in vitro and in vivo data showed that TBECH has androgenic properties. Deleterious effects of TBECH were studied on embryonic and juvenile zebrafish and qRT-PCR analysis in vitro and in vivo was performed to determine TBECH effects on gene regulation. TBECH was found to delay hatching at 1 mu M and 10 mu M doses while morphological abnormalities and juvenile mortality was observed at 10 mu M. The qRT-PCR analysis showed alterations of multiple genes involved in chondrogenesis (cartilage development), metabolism and stress response. Thus, TBECH induces androgenic activity and has negative effects on zebrafish physiology and therefore its impact on the environment should be carefully monitored. (C) 2013 Elsevier B.V. All rights reserved.

    Keywords
    Androgens, Endocrine, Endocrine disruptor, Gene regulation
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:oru:diva-32902 (URN)10.1016/j.aquatox.2013.07.018 (DOI)000328093900007 ()23958786 (PubMedID)
    Funder
    Knowledge Foundation
    Available from: 2014-01-02 Created: 2014-01-02 Last updated: 2017-12-06Bibliographically approved
    3. The brominated flame retardants TBP-AE and TBP-DBPE antagonize the chicken androgen receptor and alter gene expression in chicken LMH cells
    Open this publication in new window or tab >>The brominated flame retardants TBP-AE and TBP-DBPE antagonize the chicken androgen receptor and alter gene expression in chicken LMH cells
    (English)Manuscript (preprint) (Other academic)
    Keywords
    EDC, Avian, signaling pathways, ATE, BATE, DPTE, TBECH
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:oru:diva-43909 (URN)
    Available from: 2015-03-27 Created: 2015-03-27 Last updated: 2017-10-17Bibliographically approved
    4. In silico and biological analysis of anti-androgen activity of the brominated flame retardants ATE, BATE and DPTE in zebrafish
    Open this publication in new window or tab >>In silico and biological analysis of anti-androgen activity of the brominated flame retardants ATE, BATE and DPTE in zebrafish
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Keywords
    Brominated flame retardants, stereoidgenesis, gene regulation, hatch, teratogenesis
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:oru:diva-43911 (URN)
    Available from: 2015-03-27 Created: 2015-03-27 Last updated: 2017-10-17Bibliographically approved
  • 140.
    Asnake, Solomon
    et al.
    Örebro University, School of Science and Technology.
    Pradhan, Ajay
    Örebro University, School of Science and Technology.
    Banjop-Kharlyngdoh, Joubert
    Örebro University, School of Science and Technology.
    Modig, Carina
    Örebro University, School of Science and Technology.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH)-mediated steroid hormone receptor activation and gene regulation in chicken LMH cells2014In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 33, no 4, p. 891-899Article in journal (Refereed)
    Abstract [en]

    The incorporation of brominated flame retardants into industrial and household appliances has increased their occurrence in the environment, resulting in deleterious effects on wildlife. With the increasing restraints on available compounds, there has been a shift to using brominated flame retardants that has seen the production of alternative brominated flame retardants such as 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH), which has been detected in the environment. In previous in silico and in vitro studies the authors have shown that TBECH can activate both the human androgen receptor (hAR) and the zebrafish AR (zAR) suggesting that it is a potential endocrine disruptor. The present study was aimed at determining the interaction of TBECH with the chicken AR (cAR). In the present study, TBECH bound to cAR, but in vitro activation assay studies using the chicken LMH cell line showed it had a potency of only 15% compared with testosterone. Sequence difference between ARs from different species may contribute to the different responses to TBECH. Further quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) analysis showed that TBECH interacted with and altered the expression of both thyroid receptors and estrogen receptors. In addition, the qRT-PCR analysis showed that TBECH altered the transcription pattern of genes involved in inflammatory, apoptotic, proliferative, DNA methylation, and drug-metabolizing pathways. This demonstrates that TBECH, apart from activating cAR, can also influence multiple biological pathways in the chicken.

  • 141.
    Asnake, Solomon
    et al.
    Örebro University, School of Science and Technology.
    Pradhan, Ajay
    Biology, The Life Science Center, School of Science and Technology, Örebro University, Örebro, Sweden.
    Kharlyngdoh, Joubert Banjop
    Örebro University, School of Science and Technology.
    Modig, Carina
    Örebro University, School of Science and Technology.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    The brominated flame retardants TBP-AE and TBP-DBPE antagonize the chicken androgen receptor and act as potential endocrine disrupters in chicken LMH cells2015In: Toxicology in Vitro, ISSN 0887-2333, E-ISSN 1879-3177, Vol. 29, no 8, p. 1993-2000Article in journal (Refereed)
    Abstract [en]

    Increased exposure of birds to endocrine disrupting compounds has resulted in developmental and reproductive dysfunctions. We have recently identified the flame retardants, ally1-2,4,6-tribromophenyl ether (TBP-AE), 2-3-dibromopropy1-2,4,6-tribromophenyl ether (TBP-DBPE) and the TBP-DBPE metabolite 2-bromoallyI-2,4,6-tribromophenyl ether (TBP-BAE) as antagonists to both the human androgen receptor (AR) and the zebrafish AR. In the present study, we aimed at determining whether these compounds also interact with the chicken AR. In silico modeling studies showed that TBP-AE, TBP-BAE and TBP-DBPE were able to dock into to the chicken AR ligand-binding pocket. In vitro transfection assays revealed that all three brominated compounds acted as chicken AR antagonists, inhibiting testosterone induced AR activation. In addition, qRT-PCR studies confirmed that they act as AR antagonists and demonstrated that they also alter gene expression patterns of apoptotic, anti-apoptotic, drug metabolizing and amino acid transporter genes. These studies, using chicken LMH cells, suggest that TBP-AE, TBP-BAE and TBP-DBPE are potential endocrine disrupters in chicken.

  • 142.
    Asnake, Solomon
    et al.
    Örebro University, School of Science and Technology.
    Pradhan, Ajay
    Örebro University, School of Science and Technology.
    Kharlyngdoh, Joubert Banjop
    Örebro University, School of Science and Technology.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    The brominated flame retardants TBP-AE and TBP-DBPE antagonize the chicken androgen receptor and alter gene expression in chicken LMH cellsManuscript (preprint) (Other academic)
  • 143.
    Asplund, Anton
    et al.
    Örebro University, School of Science and Technology.
    Hanna, Gabriel
    Örebro University, School of Science and Technology.
    Using Mobile Augmented Reality and Reasoning Systems in Industrial Maintenance2018Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Inspection workers in industries, evaluates the state of machines based on assumptions to decide if a need for service exists. These assumptions varies depending on the person performing the evaluation, which can cause the wrong decision to be made. These decisions on machine service affect the economy of the industry. By using sensors mounted to the machines and a reasoning system to evaluate the data from these sensors, the condition of the machines can be determined. Augmented Reality can then be used to display this condition to the inspection worker, leading to more informed decisions about the need for service being made. This thesis examines the different technologies needed to make this possible, Augmented Reality, Reasoning Systems, and Internet of Things. A prototype application is created using these to show what is possible using the mobile devices we all carry.

  • 144.
    Atterling, Lise-Lotte
    Örebro University, School of Science and Technology.
    TAK-mätning slipmaskiner2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's Suzuki Garphyttan AB (SG) part of the Suzuki Metal Industry Group. Which is a Japanese company. SG is a world leader in the manufacturing of advanced spring wire used for various automotive applications. The core business of SG is the manufacturing and sales of valve spring wire, flat wire and profiled wire, oil quenched wire, spring wire, and stainless steel spring wire.  SG has its own manufacturing of valve springs for trucks in the Springshop. It´s located within the SG factory area. Springshop implements an improvement with the intention to changes todays functional production to line production. The customers require quality certifications and some customers have themselves wound up its quality control on for spring. The quality control and quality guarantee is then responsible for spring production. This means even higher quality and reliability of the manufacturers. Springshop improvement work to restructure from even higher quality and reliability of the manufacturers.  From the OEE-analysis of grinders machine available data and information on the reasons for include machine downtime. Through the analysis of the measurement results are obtained for the continued improvement of the grinding machine increase utilization and thus secure future production volumes.  The project undertaken was OEE-analysis of grinding machines and it has worked out well. The results that come up have led to what has previously been indications to low utilization now has been measured and documented.  Recommendation to SG is to work with preventive maintenance to have a uneven get a smoother production, a custom orders to the grinders operator are allocated to plots the day before. Order shall be within a reasonable production capacity and with the utmost focus on quality.

  • 145.
    Au Musse, Ayan
    Örebro University, School of Science and Technology.
    Characterization of the metabolic changes in chicken liver due to exposure of perfluorooctane sulfonate (PFOS) during the embryo development2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Perfluoroalkyl substances (PFASs) are anthropogenic compounds that have been classed as persistent organic pollutants (POPs) and are found in both commercial and industrial products. PFASs have been detected in different environmental matrices and have been found to bioaccumulate in all trophic levels. The adverse effects that are associated with PFAS exposure include reduced body weight, increased liver weight, hepatocellular hypertrophy, a decrease in serum cholesterol and triglycerides. This project aims to characterize the metabolic changes in lipid metabolism in the liver after exposure to one of the well-studied PFASs, the perfluorooctane sulfonate (PFOS), during the embryo development using the domestic chicken as a model organism.

    The characterization of the metabolic changes was done by conducting both quantitative lipidomic analysis and semi-quantitative global profiling on extracted lipids from liver homogenates from a former related project looking at fatty acid profiles. The extracted lipids were analyzed using UHPLC/Q-TOF-MS. In the quantitative analysis, the PFOS-treated groups (0.1 ug/g and 1.0 ug/g)exhibited higher lipid concentrations when compared with the solvent control group (5% DMSO) and the untreated group leading to the conclusion that PFOS exposure disrupts the lipid metabolism. When comparing the lipid concentrations between the two PFOS-treated groups (0.1 ug/g and 1.0 ug/g), the majority of the lipids exhibited higher lipid concentrations in the 1.0 ug/g PFOS-treated groups leading to the conclusion that the effect PFOS has on the lipid metabolism is dose dependent. In the global profiling analysis, 63 lipids showed significant differences when comparing the solvent control group with samples either treated with 0.1 ug/g PFOS or 1.0 ug/g PFOS.

  • 146.
    Aura, Anna-Marja
    et al.
    VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Mattila, Ismo
    VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Gopalacharyulu, Peddinti
    VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Bounsaythip, Catherine
    University of Helsinki, Helsinki, Finland.
    Oresic, Matej
    Örebro University, School of Medical Sciences. VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Oksman-Caldentey, Kirsi-Marja
    VTT Technical Research Centre of Finland, Espoo FI-02044 VTT, Finland.
    Drug metabolome of the simvastatin formed by human intestinal microbiota in vitro2011In: Molecular Biosystems, ISSN 1742-206X, E-ISSN 1742-2051, Vol. 7, no 2, p. 437-446Article in journal (Refereed)
    Abstract [en]

    The human colon contains a diverse microbial population which contributes to degradation and metabolism of food components. Drug metabolism in the colon is generally poorly understood. Metabolomics techniques and in vitro colon models are now available which afford detailed characterization of drug metabolites in the context of colon metabolism. The aim of this work was to identify novel drug metabolites of Simvastatin (SV) by using an anaerobic human in vitro colon model at body temperature coupled with systems biology platform, excluding the metabolism of the host liver and intestinal epithelia. Comprehensive two-dimensional gas chromatography with a time-of-flight mass spectrometry (GC×GC-TOFMS) was used for the metabolomic analysis. Metabolites showing the most significant differences in the active faecal suspension were elucidated in reference with SV fragmentation and compared with controls: inactive suspension or buffer with SV, or with active suspension alone. Finally, time courses of selected metabolites were investigated. Our data suggest that SV is degraded by hydrolytic cleavage of methylbutanoic acid from the SV backbone. Metabolism involves demethylation of dimethylbutanoic acid, hydroxylation/dehydroxylation and β-oxidation resulting in the production of 2-hydroxyisovaleric acid (3-methyl-2-hydroxybutanoic acid), 3-hydroxybutanoic acid and lactic acid (2-hydroxypropanoic acid), and finally re-cyclisation of heptanoic acid (possibly de-esterified and cleaved methylpyranyl arm) to produce cyclohexanecarboxylic acid. Our study elucidates a pathway of colonic microbial metabolism of SV as well as demonstrates the applicability of the in vitro colon model and metabolomics to the discovery of novel drug metabolites from drug response profiles.

  • 147.
    Ax, Erika
    et al.
    Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
    Lampa, Erik
    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
    Department of Medical Sciences, Cardiovascular Epidemiology, Uppsala University, Uppsala, Sweden.
    van Bavel, Bert
    Örebro University, School of Science and Technology. MTM Research Centre, Örebro University, Örebro, Sweden.
    Cederholm, Tommy
    Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
    Sjögren, Per
    Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
    Lind, P. Monica
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    Circulating levels of environmental contaminants are associated with dietary patterns in older adults2015In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 75, p. 93-102Article in journal (Refereed)
    Abstract [en]

    Background: Food intake contributes substantially to our exposure to environmental contaminants. Still, little is known about our dietary habits' contribution to exposure variability.

    Objective: The aim of this study was to assess circulating levels of environmental contaminants in relation to predefined dietary patterns in an elderly Swedish population.

    Methods: Dietary data and serum concentrations of environmental contaminants were obtained from 844 70-year-old Swedish subjects (50% women) in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Dietary data from 7-day food records was used to assess adherence to a Mediterranean-like diet, a low carbohydrate-high protein diet and the WHO dietary recommendations. Circulating levels of 6 polychlorinated biphenyl markers, 3 organochlorine pesticides, 1 dioxin and 1 polybrominated diphenyl ether, the metals cadmium, lead, mercury and aluminum and serum levels of bisphenol A and 4 phthalate metabolites were investigated in relation to dietary patterns in multivariate linear regression models.

    Results: A Mediterranean-like diet was positively associated with levels of several polychlorinated biphenyls (118, 126, 153, and 209), trans-nonachlor and mercury. A low carbohydrate-high protein diet was positively associated with polychlorinated biphenyls 118 and 153, trans-nonachlor, hexachlorobenzene and p, p'-dichlorodiphenyldichloroethylene, mercury and lead. The WHO recommended diet was negatively related to levels of dioxin and lead, and borderline positively to polychlorinated biphenyl 118 and trans-nonachlor.

    Conclusion: Dietary patterns were associated in diverse manners with circulating levels of environmental contaminants in this elderly Swedish population. Following the WHO dietary recommendations seems to be associated with a lower burden of environmental contaminants.

  • 148.
    Ax, Erika
    et al.
    Uppsala Univeristy, Sweden.
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    Lind, P. Monica
    Occupational & Environmental Medicine UU, Sweden.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, Lars
    Acute & Internal Medicine, UU, Sweden.
    Lampa, Erik
    Occupational & Environmental Medicine UU, Sweden.
    Sjögren, Per
    Clinical Nutrition & Metabolism, UU, Sweden.
    Circulating levels of environmental contaminants are associated with dietary pattern2012In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 211, no Supplement, p. S101-S101Article in journal (Refereed)
  • 149.
    Axdorff, Louise
    Örebro University, School of Science and Technology.
    Upptag av polycykliska aromatiska kolväten från olika kontaminerade jordar i daggmask (Eisenia Fetida)2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Många antropogena ämnen är toxiska och har lång halveringstid och återfinns därför lång tid efter att de hamnat i miljön. Ett exempel är polycykliska aromatiska kolväten (PAH), som bildas vid ofullständig förbränning av organiskt material och som kan förekomma i höga halter vid före detta gasverk och gamla träimpregneringsplatser där kreosotimpregnering förekommit. I marken på dessa områden kan halterna av PAH vara mycket höga, och det kan påverka markekosystemet negativt. En viktig markorganism är daggmask, som har stor betydelse i många markekosystem. Därför är det viktigt att veta om PAHer i mark är tillgängliga för upptag i mask, eftersom det kan påverka masken negativt. Dessutom skulle eventuella PAHer i mask kunna transporteras vidare i näringskedjor. Syftet med studien var därför att undersöka upptaget av polycykliska aromatiska kolväten (PAH) i Eisenia Fetida från förorenad jord. E. Fetida exponerades under två veckor för nio olika PAH-förorenade jordar som samlats in från två kreosotförorenade områden, en före detta gasverkstomt och en bangård. Sammanlagt 24 PAHer inklusive PAH16 analyserades i jord och mask med GC/MS. Resultaten visade upptag av PAHer i E. Fetida från samtliga jordprov, men upptaget varierade beroende på prov. Ett jordprov från en före detta gasverkstomt, gasverk c hade den högsta uppmätta totala bioackumuleringsfaktorn (BAF) för PAHer från respektive prov. De enskilda BAF-värdena i jorden var högre för de högmolekylära PAHerna, medan jordprov insamlade på en bangård visade på ett högre upptag i mask av de låg- och mellan molekylära PAHerna. Ett av de kreosotförorenade jordproverna, kreosot a hade det högsta enskilda BAF-värdet för PAHer, vilket var trifenylen som hade en BAF 18.Det var inget signifikant samband mellan PAH-halten i jordarna och PAH-halten i mask, vilket tyder på att upptaget i mask inte enbart beror på halten PAHer i jorden. Det var heller inget signifikant samband mellan halten organiskt material och upptaget av PAHer i E. Fetida, men resultaten tyder på att upptaget i E. Fetida beror mer på jordegenskaper som organiskt material än halterna av PAHer i jorden. Det är därför viktigt att fortsätta forska kring PAHer och biotillgänglighet i mark.

  • 150.
    Aydin, Ayhan
    Örebro University, School of Science and Technology.
    Påverkas smaken på höns av foder, genmaterial och tillagningsmetoder?2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Få produkter i Sverige innehåller idag höns däremot ökar konsumtionen av ägg. Den ojämna balansen mellan ökad äggproduktion och minskad konsumtion av höna tycks vara en uppåtgående trend. Höns som livsmedel har utgått i det ordinarie sortimentet hos de stora livsmedelskedjorna. Livsmedelsproducenter har slutat använda höns på grund av ”kvalitetsbrister” som att de har fått skört skelett. I och med det kan benflisor komma med i köttet. Huvudsakligen är hönsen avlade för att producera mycket ägg - ett om dagen, i stora grupper. Dessa djur är anpassade för storskalig produktion med många djur på en liten yta. Den separering som skett mellan slaktkycklingar och värphöns med början på 1920-talet kan varit en del av förklaringen med minskad hönskötts konsumtion. Hos äldre djur finns det mer bindväv och fettansamling. Den ökade mängden bindväv gör att konsistensen på köttet uppfattas segare men också saftigare, då fett ansamlas där. Substanserna som finns i fettvävnaden, ger upphov till den karaktäristiska smaken och aromen som finns i köttet. Det blir tydligare vid upphettning. När ett djur blir äldre ökar mängden bindväv och dess tvärbindningar, som både stabiliserar men även blir mer värmetåliga. Desto mer ett djuret rör på sig, blir de röda muskelfibrerna aktiva och bildar en grövre struktur. Åldern tillsammans med rörelse kan också skapa ett mer smakrikt kött men även ett segare kött av större fibrer i bindväven som behöver längre tillagningstid.

    I denna studie undersöktes smak samt textur av foder och genmaterial med två olika tillagningsmetoder, kokning samt sous-vide. En panel utvärderade det utifrån 13 variabler. Där det fanns en tydligast signifikans var skillnaden mellan lår och bröst. Att dela upp höns i bröst och lår/vingar gör att förutsättningarna för en mer exakt tillagning ökar. De variabler som hade en signifikans när en PCA-analys gjordes var: textur: saftighet, fethet; smak: härsken; doft: umami, härsket. När t-test utfördes blev det signifikans på saftighet, fethet, smak av härsket och doften av umami. Variablerna som tydligast skilde sig åt mellan bröst och lår var texturerna, saftighet och fethet. Det var ingen signifikant skillnad mellan genotyperna, tillagning eller foder.

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