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  • 251.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    From Feature Detection in Truncated Signed Distance Fields to Sparse Stable Scene Graphs2016In: IEEE Robotics and Automation Letters, ISSN 2377-3766, Vol. 1, no 2, 1148-1155 p.Article in journal (Refereed)
    Abstract [en]

    With the increased availability of GPUs and multicore CPUs, volumetric map representations are an increasingly viable option for robotic applications. A particularly important representation is the truncated signed distance field (TSDF) that is at the core of recent advances in dense 3D mapping. However, there is relatively little literature exploring the characteristics of 3D feature detection in volumetric representations. In this paper we evaluate the performance of features extracted directly from a 3D TSDF representation. We compare the repeatability of Integral invariant features, specifically designed for volumetric images, to the 3D extensions of Harris and Shi & Tomasi corners. We also study the impact of different methods for obtaining gradients for their computation. We motivate our study with an example application for building sparse stable scene graphs, and present an efficient GPU-parallel algorithm to obtain the graphs, made possible by the combination of TSDF and 3D feature points. Our findings show that while the 3D extensions of 2D corner-detection perform as expected, integral invariants have shortcomings when applied to discrete TSDFs. We conclude with a discussion of the cause for these points of failure that sheds light on possible mitigation strategies.

  • 252.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Improved local shape feature stability through dense model tracking2013In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2013, 3203-3209 p.Conference paper (Refereed)
    Abstract [en]

    In this work we propose a method to effectively remove noise from depth images obtained with a commodity structured light sensor. The proposed approach fuses data into a consistent frame of reference over time, thus utilizing prior depth measurements and viewpoint information in the noise removal process. The effectiveness of the approach is compared to two state of the art, single-frame denoising methods in the context of feature descriptor matching and keypoint detection stability. To make more general statements about the effect of noise removal in these applications, we extend a method for evaluating local image gradient feature descriptors to the domain of 3D shape descriptors. We perform a comparative study of three classes of such descriptors: Normal Aligned Radial Features, Fast Point Feature Histograms and Depth Kernel Descriptors; and evaluate their performance on a real-world industrial application data set. We demonstrate that noise removal enabled by the dense map representation results in major improvements in matching across all classes of descriptors as well as having a substantial positive impact on keypoint detection reliability

  • 253.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    SDF tracker: a parallel algorithm for on-line pose estimation and scene reconstruction from depth images2013In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2013, 3671-3676 p.Conference paper (Refereed)
    Abstract [en]

    Ego-motion estimation and environment mapping are two recurring problems in the field of robotics. In this work we propose a simple on-line method for tracking the pose of a depth camera in six degrees of freedom and simultaneously maintaining an updated 3D map, represented as a truncated signed distance function. The distance function representation implicitly encodes surfaces in 3D-space and is used directly to define a cost function for accurate registration of new data. The proposed algorithm is highly parallel and achieves good accuracy compared to state of the art methods. It is suitable for reconstructing single household items, workspace environments and small rooms at near real-time rates, making it practical for use on modern CPU hardware

  • 254.
    Canelhas, Daniel Ricão
    Örebro University, School of Science and Technology.
    Truncated Signed Distance Fields Applied To Robotics2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis is concerned with topics related to dense mapping of large scale three-dimensional spaces. In particular, the motivating scenario of this work is one in which a mobile robot with limited computational resources explores an unknown environment using a depth-camera. To this end, low-level topics such as sensor noise, map representation, interpolation, bit-rates, compression are investigated, and their impacts on more complex tasks, such as feature detection and description, camera-tracking, and mapping are evaluated thoroughly. A central idea of this thesis is the use of truncated signed distance fields (TSDF) as a map representation and a comprehensive yet accessible treatise on this subject is the first major contribution of this dissertation. The TSDF is a voxel-based representation of 3D space that enables dense mapping with high surface quality and robustness to sensor noise, making it a good candidate for use in grasping, manipulation and collision avoidance scenarios.

    The second main contribution of this thesis deals with the way in which information can be efficiently encoded in TSDF maps. The redundant way in which voxels represent continuous surfaces and empty space is one of the main impediments to applying TSDF representations to large-scale mapping. This thesis proposes two algorithms for enabling large-scale 3D tracking and mapping: a fast on-the-fly compression method based on unsupervised learning, and a parallel algorithm for lifting a sparse scene-graph representation from the dense 3D map.

    The third major contribution of this work consists of thorough evaluations of the impacts of low-level choices on higher-level tasks. Examples of these are the relationships between gradient estimation methods and feature detector repeatability, voxel bit-rate, interpolation strategy and compression ratio on camera tracking performance. Each evaluation thus leads to a better understanding of the trade-offs involved, which translate to direct recommendations for future applications, depending on their particular resource constraints.

  • 255.
    Carlberg, Michael
    et al.
    Univ Orebro, Dept Oncol, Fac Med & Hlth, SE-70182 Orebro, Sweden..
    Hardell, Lennart
    Örebro University, School of Science and Technology. Dept Oncol.
    Pooled analysis of Swedish case-control studies during 1997-2003 and 2007-2009 on meningioma risk associated with the use of mobile and cordless phones2015In: Oncology Reports, ISSN 1021-335X, E-ISSN 1791-2431, Vol. 33, no 6, 3093-3098 p.Article in journal (Refereed)
    Abstract [en]

    A pooled analysis of two case-control studies on meningioma with patients diagnosed during 1997-2003 and 2007-2009 was conducted. Both genders were included, aged 20-80 and 18-75 years, respectively, at the time of diagnosis. Population-based controls, matched according to age and gender, were enrolled. Exposure was assessed by questionnaire. In the entire study, cases with all brain tumor types were included. The whole reference group was used in the unconditional logistic regression analysis on meningioma, with adjustments for gender, age, year of diagnosis and socioeconomic index (SEI). In total, 1,625 meningioma cases and 3,530 controls were analyzed. Overall no association with use of mobile or cordless phones was found. In the fourth quartile of use (>1,436 h) somewhat increased risk was found for mobile phones yielding an odds ratio (OR)=1.2, 95% confidence intervals (CI)=0.9-1.6 and cordless phones OR=1.7, 95% CI=1.3-2.2. Higher risk was calculated in the highest decile (>3,358 h), OR=1.5, 95% CI=0.99-2.1 and OR=2.0, 95% CI=1.4-2.8, respectively. In addition, the longest latency time gave somewhat increased risk for both phone types although the result was not statistically significant. There was no association for ipsilateral use or anatomical tumor location. The present study showed a somewhat increased risk among heavy users of mobile and cordless phones. Since meningioma is generally a slow-growing tumor, longer latency period is necessary for definitive conclusions.

  • 256.
    Carling, Johan
    et al.
    Örebro University, School of Science and Technology.
    Morenga, Magnus
    Örebro University, School of Science and Technology.
    Vibrationsanalys i en solidfräs2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Volvo Powertrain in Köping manufactures bevel gears used in the process of gear kits used in marine transmissions from Volvo Penta. In order to manufacture these gears a solid cutter is used. The wear on the cuttingtool increases with the number of details that are produced. As the cutter becomes more worn, it is harder to cut the material and the vibration increases.

    After a predetermined number of parts is processed the cutting edges is sharpened. However, this predetermined number is only an estimated number of how much the cutter can handle. The aim was to investigate if the cutter was able to process more details than they are doing today, before a sharpening of the cutting edges is necessary.

    Using an accelerometer, a vibration analysis has been performed. By comparing vibration data with the measurement deviation, a limit was set when the part's dimensions were no longer approved.

    In report we present two different strategies that can be used to determine when the cutter has to be replaced. However, in order to ensure that the strategy is working more testing is needed.

  • 257.
    Carlsson, Johannes
    et al.
    Örebro University, School of Science and Technology.
    Hägglund, Jonatan
    Örebro University, School of Science and Technology.
    Att utöka noggrannheten i mätsystemet HiMacs2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The industry is now entirely dependent on computer systems in various parts of the

    organization. As systems become more powerful the opportunities for increased control and

    precision grows. The more defects and faults that can be detected before delivery, more

    customer satisfaction is obtained which leads to fewer unnecessary costs connected to, for

    example, recalls. Of course, this is desirable from the industry and leads to higher demands

    for information systems.

     

    This report discusses the opportunities to increase the measuring frequency of an existing

    industrial realtime system running on a PC with Windows as operating system that is

    designed for test runs and measurements of engines and transmissions. Limitations that

    comes with using a nonreal time operating system in a real time industrial application is

    cleared up. The option for real time communication that HiMacs uses, developed by

    Beckhoff Automation, is also described.

     

    The project was investigative and various proposed solutions were developed and compared

    to each other to achieve the most reliable solution.

  • 258.
    Carlsson, Sofia
    Örebro University, School of Science and Technology.
    Vad påverkar elevers attityder till matematik?: En systematisk litteraturstudie med fokus på hur positiva attityder kan främjas.2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In society today, mathematics appears to be a boring and difficult subject that only some people can manage. Many students have negative attitudes towards the subject, which means that their interest in what is thought in the math lessons decreases and they are missing out on opportunities to learn. To promote pupils' learning in mathematics and to prevent students from taking their negative attitudes into adulthood, the present study aims to investigate what effects various kinds of influences may have on students’ attitudes towards mathematics and, above all, how they can be positively influenced. For the survey, a systematic literature study has been used and the basis for the compiled research overview has been retrieved from the Web of Science database. The results of the study indicate that there are several types of influences on pupils’ attitudes towards mathematics and that the influence both can have a positive and a negative effect depending on how it is handled and expressed. However, the most important types of influences can be summarized into social factors, the students' perspective on the subject and on who they think can manage it and the student´s believes of mathematics and the teaching as a meaningful subject.

  • 259.
    Carlsson, Ulrika
    et al.
    Örebro University, School of Science and Technology.
    Collstam, Viktoria
    Örebro University, School of Science and Technology.
    Visualisering av respektive stations takttid på en specifik monteringsbana på GKN Driveline i Köping AB2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis was performed on the department of assembling at GKN Driveline AB in Koping, where final- and bevel gear is assembled and then provided to global customers in the car industry.

    The total rate for the assembly line which this project included is 64 seconds, but in the current situation the total rate is often higher. The problem is that it’s not possible to see if the assembler tact right or not on each assembly station, resulting in that it’s not possible to identify where on the line the time loss occurs and where the root cause lies in a rate that’s too high, when there’s no indicator on that.

    The aim of this project was to produce a solution that makes it possible for the assembler to see the rate on each station. Advantages and disadvantages with a visualization was analyzed, evaluated and presented, and an overall cost estimate was also produced. The written report works as a foundation for a possible future implementation.

    The basis of the thesis were literature studies in the areas of Lean production and stress, external benchmarking to collect information and inspiration, and also interviews with the employees at GKN Driveline to highlight the views and thoughts on a possible effect of a visualization on humans. In addition to the collecting of the different information above a proprietary method for the production of the final solution was implemented.

    The final solution that was produced was an enhancement to the company’s already existing industrial system. The product visualizes the rate for the assembler and records and stores data which entails several advantages. A discussion about how the visualization will be as efficient as possible together with final recommendations have been presented and if the implementation is carried out and improves the production result the visualization can be usefully applied to all the company’s assembly lines.

  • 260. Carpin, Stefano
    et al.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Nevatia, Yashodhan
    Lewis, M.
    Wang, J.
    Quantitative Assessments of USARSim Accuracy2006Conference paper (Refereed)
  • 261.
    Carvalho, Raquel N.
    et al.
    European Commission-DG Joint Research Centre, Institute for Environment and Sustainability, Italy.
    Arukwe, Augustine
    Norwegian University of Science & Technology, Trondheim, Norway.
    Ait-Aissa, Selim
    National Institute for Industrial Environment and Risks, Verneuil en Halatte, France.
    Bado-Nilles, Anne
    National Institute for Industrial Environment and Risks, Verneuil en Halatte, France Reims University, France.
    Balzamo, Stefania
    Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Rome, Italy.
    Baun, Anders
    Department of Environmental Engineering,Technical University of Denmark, Kgs Lyngby, Denmark.
    Belkin, Shimshon
    Institute of Life Sciences, The Hebrew University of Jerusalem, Israel.
    Blaha, Ludek
    Faculty of Science, Masaryk University, RECETOX, Brno, Czech Republic.
    Brion, Francois
    National Institute for Industrial Environment and Risks, Verneuil en Halatte, France.
    Conti, Daniela
    Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Rome, Italy.
    Creusot, Nicolas
    National Institute for Industrial Environment and Risks, Verneuil en Halatte, France.
    Essig, Yona
    Analytical and Environmental Sciences Division, King's College London, UK.
    Ferrero, Valentina E. V.
    European Commission-DG Joint Research Centre, Institute for Environment and Sustainability, Italy.
    Flander-Putrle, Vesna
    Marine Biology Station Piran, National Institute of Biology, Slovenia.
    Furhacker, Maria
    University of Natural Resources and Life Sciences, Vienna, Austria.
    Grillari-Voglauer, Regina
    University of Natural Resources and Life Sciences, Vienna, Austria.
    Hogstrand, Christer
    Diabetes and Nutritional Sciences Division, King's College London, UK.
    Jonas, Adam
    Faculty of Science, Masaryk University, RECETOX, Brno, Czech Republic.
    Kharlyngdoh, Joubert B.
    Örebro University, School of Science and Technology.
    Loos, Robert
    European Commission-DG Joint Research Centre, Institute for Environment and Sustainability, Italy.
    Lundebye, Anne-Katrine
    National Institute of Nutrition and Seafood Research, Bergen, Norway.
    Modig, Carina
    Örebro University, School of Science and Technology. Life Science Center, Örebro University, Sweden.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology. Life Science Center, Örebro University, Sweden.
    Pillai, Smitha
    University of Natural Resources and Life Sciences, Vienna, Austria.
    Polak, Natasa
    Analytical and Environmental Sciences Division, King's College London, UK.
    Potalivo, Monica
    Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Rome, Italy.
    Sanchez, Wilfried
    National Institute for Industrial Environment and Risks, Verneuil en Halatte, France.
    Schifferli, Andrea
    Swiss Centre for Applied Ecotoxicology, Eawag-EPFL, Dübendorf, Switzerland.
    Schirmer, Kristin
    Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; ETH Zürich, Department of Environmental Systems Science, Swiss Federal Institute of Technology, Zürich, Switzerland; EPF Lausanne, School of Architecture, Civil and Environmental Engineering, Lausanne, Switzerland.
    Sforzini, Susanna
    Department of Environmental and Life Sciences, Università del Piemonte Orientale Vercelli Novara Alessandria, Alessandria, Italy.
    Sturzenbaum, Stephen R.
    Analytical and Environmental Sciences Division, King's College London, UK.
    Søfteland, Liv
    National Institute of Nutrition and Seafood Research, Bergen, Norway.
    Turk, Valentina
    Marine Biology Station Piran, National Institute of Biology, Slovenia.
    Viarengo, Aldo
    Department of Environmental and Life Sciences, Università del Piemonte Orientale Vercelli Novara Alessandria, Alessandria, Italy.
    Werner, Inge
    Swiss Centre for Applied Ecotoxicology, Eawag-EPFL, Dübendorf, Switzerland.
    Yagur-Kroll, Sharon
    Institute of Life Sciences, The Hebrew University of Jerusalem, Israel.
    Zounkova, Radka
    Faculty of Science, Masaryk University, RECETOX, Brno, Czech Republic.
    Lettieri, Teresa
    European Commission-DG Joint Research Centre, Institute for Environment and Sustainability, Italy.
    Mixtures of chemical pollutants at European legislation safety concentrations: how safe are they?2014In: Toxicological Sciences, ISSN 1096-6080, E-ISSN 1096-0929, Vol. 141, no 1, 218-233 p.Article in journal (Refereed)
    Abstract [en]

    The risk posed by complex chemical mixtures in the environment to wildlife and humans is increasingly debated, but has been rarely tested under environmentally relevant scenarios. To address this issue, two mixtures of 14 or 19 substances of concern (pesticides, pharmaceuticals, heavy metals, polyaromatic hydrocarbons, a surfactant, and a plasticizer), each present at its safety limit concentration imposed by the European legislation, were prepared and tested for their toxic effects. The effects of the mixtures were assessed in 35 bioassays, based on 11 organisms representing different trophic levels. A consortium of 16 laboratories was involved in performing the bioassays. The mixtures elicited quantifiable toxic effects on some of the test systems employed, including i) changes in marine microbial composition, ii) microalgae toxicity, iii) immobilization in the crustacean Daphnia magna, iv) fish embryo toxicity, v) impaired frog embryo development, and vi) increased expression on oxidative stress-linked reporter genes. Estrogenic activity close to regulatory safety limit concentrations was uncovered by receptor-binding assays. The results highlight the need of precautionary actions on the assessment of chemical mixtures even in cases where individual toxicants are present at seemingly harmless concentrations.

  • 262.
    Caspillo, Nasim Reyhanian
    Örebro University, School of Science and Technology.
    Hitting the mark: studies of alterations in behaviour and fertility in ethinyl estradiol-exposed zebrafish and search related biomarkers2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, we have analysed the effects of EE2 on non-reproductive behaviours and fertility. We have showed that two doses of EE2 in male adult short-term exposures evokes opposite behaviours in the novel tank test. A lower dose induced increased bottom-dwelling, a sign of increased anxiety and a higher dose increased surface-dwelling, which would likely expose themselves to predation in a natural environment. Increased shoaling was observed in both exposures, possibly affecting feeding and reproduction opportunities. Fertility analysis of these fish demonstrated a complete inhibition of spawning in the highest dose group. To investigate mechanisms behind the spawning failure, we examined expression levels of genes involved in zebrafish sex differentiation and maintenance of gonadal function. We found downregulated transcription levels of male-predominant genes, suggesting a demasculinization of the testes contributing to functional sterility in these fish. We have demonstrated that non-reproductive behaviour in zebrafish is highly sensitive to EE2 exposure during development. After exposing male and female zebrafish to low doses of EE2 followed by remediation in clean water until adulthood, the fish displayed increased anxiety and shoaling behaviour, demonstrating persistent effects of EE2. Furthermore, behavioural effects were transferred to their progeny. Decreased fertilisation success of the developmentally exposed fish was observed in both sexes when mated to untreated animals of the opposite sex. These fertility effects persisted although the fish had a long remediation period, implying likely reduced fitness of fish populations in aquatic environments. Based on our findings on non-reproductive behaviours and fertility, we performed RNAsequencing analysis of the brain and testes in order to investigate possible biological mechanisms behind the persistent effects. There is a need for biomarkers allowing detection of both reversible and irreversible effects in animals exposed to estrogenic substances, hopefully contributing to better risk assessments for EDCs. Results from RNA-sequencing would serve as a basis for continued studies in pursuit of potential biomarkers.

    List of papers
    1. 17 alpha-Ethinyl estradiol affects anxiety and shoaling behavior in adult male zebra fish (Danio rerio)
    Open this publication in new window or tab >>17 alpha-Ethinyl estradiol affects anxiety and shoaling behavior in adult male zebra fish (Danio rerio)
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    2011 (English)In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 105, no 1-2, 41-48 p.Article in journal (Refereed) Published
    Abstract [en]

    Ethinyl estradiol is a potent endocrine disrupting compound in fish and ubiquitously present in the aquatic environment. In this study, we exposed adult zebra fish (Danio rerio) males to 0,5 or 25 ng Ethinyl estradiol/L for 14 days and analyzed the effects on non-reproductive behavior. Effects of treatment of the exposed males was shown by vitellogenin induction, while brain aromatase (CYP 19B) activity was not significantly altered. Both concentrations of Ethinyl estradiol significantly altered the behavior in the Novel tank test, where anxiety is determined as the tendency to stay at the bottom when introduced into an unfamiliar environment. The effects were, however, opposite for the two concentrations. Fish that were exposed to 5 ng/L had longer latency before upswim, fewer transitions to the upper half and shorter total time spent in the upper half compared with control fish, while 25 ng Ethinyl estradiol treatment resulted in shorter latency and more and longer visits to the upper half. The swimming activity of 25, but not 5 ng-exposed fish were slightly but significantly reduced, and these fish tended to spend a lot of time at the surface. We also studied the shoaling behavior as the tendency to leave a shoal of littermates trapped behind a Plexiglas barrier at one end of the test tank. The fish treated with Ethinyl estradiol had significantly longer latency before leaving shoal mates and left the shoal fewer times. Further, the fish exposed to 5 ng/L also spent significantly less time away from shoal than control fish. Fertilization frequency was higher in males exposed to 5 ng/L Ethinyl estradiol when compared with control males, while no spawning was observed after treatment with 25 ng/L The testes from both treatment groups contained a normal distribution of spermatogenesis stages, and no abnormality in testis morphology could be observed. In conclusion, we have observed effects on two behaviors not related to reproduction in zebra fish males after treatment with Ethinyl estradiol, adding to the ecological consequences of contamination of aquatic environments with estrogenic substances. (C) 2011 Elsevier B.V. All rights reserved.

    National Category
    Biological Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-18647 (URN)10.1016/j.aquatox.2011.05.009 (DOI)000294317500005 ()
    Available from: 2011-09-30 Created: 2011-09-29 Last updated: 2017-10-17Bibliographically approved
    2. Short-term treatment of adult male zebrafish (Danio Rerio) with 17α-ethinyl estradiol affects the transcription of genes involved in development and male sex differentiation.
    Open this publication in new window or tab >>Short-term treatment of adult male zebrafish (Danio Rerio) with 17α-ethinyl estradiol affects the transcription of genes involved in development and male sex differentiation.
    Show others...
    2014 (English)In: Comparative Biochemistry and Physiology - Part C: Toxicology & Pharmacology, ISSN 1532-0456, E-ISSN 1878-1659, Vol. 164, 35-42 p.Article in journal (Refereed) Published
    Abstract [en]

    The synthetic estrogen 17α-ethinyl estradiol (EE2) disturbs reproduction and causes gonadal malformation in fish. Effects on the transcription of genes involved in gonad development and function that could serve as sensitive biomarkers of reproductive effects in the field is, however, not well known. We have studied mRNA expression in testes and liver of adult zebrafish (Danio rerio) males treated with 0, 5 or 25ng/L EE2for 14days. qPCR analysis showed that the mRNA expression of four genes linked to zebrafish male sex determination and differentiation, Anti-Mullerian Hormone, Double sex and mab-related protein, Sry-related HMG box-9a and Nuclear receptor subfamily 5 group number 1b were significantly decreased by 25ng/L, but not 5ng/L EE2 compared with the levels in untreated fish. The decreased transcription was correlated with a previously shown spawning failure in these males (Reyhanian et al., 2011. Aquat Toxicol 105, 41-48), suggesting that decreased mRNA expression of genes regulating male sexual function could be involved in the functional sterility. The mRNA level of Cytochrome P-45019a, involved in female reproductive development, was unaffected by hormone treatment. The transcription of the female-specific Vitellogenin was significantly induced in testes. While testicular Androgen Receptor and the Estrogen Receptor-alpha mRNA levels were unchanged, Estrogen receptor-beta was significantly decreased by 25ng/L EE2. Hepatic Estrogen Receptor-alpha mRNA was significantly increased by both exposure concentrations, while Estrogen Receptor-beta transcription was unaltered. The decreased transcription of male-predominant genes supports a demasculinization of testes by EE2 and might reflect reproductive disturbances in the environment.

    Place, publisher, year, edition, pages
    New York: Elsevier, 2014
    Keyword
    17 alpha-Ethinyl estradiol; Biomarker; Endocrine disruptors; Gene regulation; Gonads; Sex differentiation; Zebrafish
    National Category
    Natural Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-35475 (URN)10.1016/j.cbpc.2014.04.003 (DOI)000337769100005 ()24747828 (PubMedID)2-s2.0-84899872779 (Scopus ID)
    Note

    Funding Agencies:

    Swedish Baltic Sea Foundation

    Stockholm County Council

    Available from: 2014-06-24 Created: 2014-06-24 Last updated: 2017-10-17Bibliographically approved
    3. Developmental exposure of zebrafish (Danio rerio) to 17 alpha-ethinylestradiol affects non-reproductive behavior and fertility as adults, and increases anxiety in unexposed progeny
    Open this publication in new window or tab >>Developmental exposure of zebrafish (Danio rerio) to 17 alpha-ethinylestradiol affects non-reproductive behavior and fertility as adults, and increases anxiety in unexposed progeny
    Show others...
    2015 (English)In: Hormones and Behavior, ISSN 0018-506X, E-ISSN 1095-6867, Vol. 73, 30-38 p.Article in journal (Refereed) Published
    Abstract [en]

    Exposure to estrogenic endocrine disruptors (EDCs) during development affects fertility, reproductive and nonreproductive behavior in mammals and fish. These effects can also be transferred to coming generations. In fish, the effects of developmental EDC exposure on non-reproductive behavior are less well studied. Here, we analyze the effects of 17 alpha-ethinylestradiol (EE2) on anxiety, shoaling behavior and fertility in zebrafish after developmental treatment and remediation in clean water until adulthood. Zebrafish embryos were exposed from day 1 to day 80 post fertilization to actual concentrations of 1.2 and 1.6 ng/L EE2. After remediation for 82 days non-reproductive behavior and fertilization success were analyzed in both sexes. Males and females from the 1.2 ng/L group, as well as control males and females, were bred, and behavior of the untreated F1 offspring was tested as adults. Developmental treatment with 12 and 1.6 ng/L EE2 significantly increased anxiety in the novel tank test and increased shoaling intensity in both sexes. Fertilization success was significantly reduced by EE2 in both sexes when mated with untreated fish of opposite sex. Progeny of fish treated with 1.2 ng/L EE2 showed increased anxiety in the novel tank test and increased light avoidance in the scototaxis test compared to control offspring. In conclusion, developmental exposure of zebrafish to low doses of EE2 resulted in persistent changes in behavior and fertility. The behavior of unexposed progeny was affected by their parents' exposure, which might suggest transgenerational effects.

    Keyword
    Endocrine disruptors, 17 alpha-Ethinylestradiol, Stress behavior, Developmental exposure, Zebrafish, Neuroendocrinology, Social behavior, Anxiety, F1 effects, Fertility
    National Category
    Biological Sciences
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-45884 (URN)10.1016/j.yhbeh.2015.05.014 (DOI)000360251800005 ()26072466 (PubMedID)2-s2.0-84934983120 (Scopus ID)
    Note

    Funding Agency:

    Swedish Baltic Sea Foundation 1742/42/2008 1556/42/2011

    Available from: 2015-09-23 Created: 2015-09-21 Last updated: 2017-10-17Bibliographically approved
    4. Testis transcriptome alterations in zebrafish (Danio rerio) with reduced fertility due to developmental exposure to 17α-ethinyl estradiol
    Open this publication in new window or tab >>Testis transcriptome alterations in zebrafish (Danio rerio) with reduced fertility due to developmental exposure to 17α-ethinyl estradiol
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Biological Topics
    Research subject
    Biology
    Identifiers
    urn:nbn:se:oru:diva-47887 (URN)
    Available from: 2016-02-02 Created: 2016-02-02 Last updated: 2017-10-17Bibliographically approved
    5. Persistent effects of developmental exposure to 17α-ethinylestradiol on the zebrafish (Danio rerio) brain transcriptome and stress behavior
    Open this publication in new window or tab >>Persistent effects of developmental exposure to 17α-ethinylestradiol on the zebrafish (Danio rerio) brain transcriptome and stress behavior
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Zoology Biochemistry and Molecular Biology
    Identifiers
    urn:nbn:se:oru:diva-45958 (URN)
    Available from: 2015-09-30 Created: 2015-09-30 Last updated: 2017-10-17Bibliographically approved
  • 263.
    Caspillo, Nasim Reyhanian
    et al.
    Södertörn Univ, Sch Nat Sci Technol & Environm Studies, SE-14189 Huddinge, Sweden; Univ Örebro, Örebro Life Sci Ctr, Sch Sci & Technol, Örebro, Sweden.
    Volkova, Kristina
    Södertörn Univ, Sch Nat Sci Technol & Environm Studies, SE-14189 Huddinge, Sweden; Univ Örebro, Örebro Life Sci Ctr, Sch Sci & Technol, Örebro, Sweden.
    Hallgren, Stefan
    Södertörn Univ, Sch Nat Sci Technol & Environm Studies, Huddinge, Sweden.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Porsch-Hällström, Inger
    Södertörn Univ, Sch Nat Sci Technol & Environm Studies, Huddinge, Sweden.
    Short-term treatment of adult male zebrafish (Danio Rerio) with 17α-ethinyl estradiol affects the transcription of genes involved in development and male sex differentiation.2014In: Comparative Biochemistry and Physiology - Part C: Toxicology & Pharmacology, ISSN 1532-0456, E-ISSN 1878-1659, Vol. 164, 35-42 p.Article in journal (Refereed)
    Abstract [en]

    The synthetic estrogen 17α-ethinyl estradiol (EE2) disturbs reproduction and causes gonadal malformation in fish. Effects on the transcription of genes involved in gonad development and function that could serve as sensitive biomarkers of reproductive effects in the field is, however, not well known. We have studied mRNA expression in testes and liver of adult zebrafish (Danio rerio) males treated with 0, 5 or 25ng/L EE2for 14days. qPCR analysis showed that the mRNA expression of four genes linked to zebrafish male sex determination and differentiation, Anti-Mullerian Hormone, Double sex and mab-related protein, Sry-related HMG box-9a and Nuclear receptor subfamily 5 group number 1b were significantly decreased by 25ng/L, but not 5ng/L EE2 compared with the levels in untreated fish. The decreased transcription was correlated with a previously shown spawning failure in these males (Reyhanian et al., 2011. Aquat Toxicol 105, 41-48), suggesting that decreased mRNA expression of genes regulating male sexual function could be involved in the functional sterility. The mRNA level of Cytochrome P-45019a, involved in female reproductive development, was unaffected by hormone treatment. The transcription of the female-specific Vitellogenin was significantly induced in testes. While testicular Androgen Receptor and the Estrogen Receptor-alpha mRNA levels were unchanged, Estrogen receptor-beta was significantly decreased by 25ng/L EE2. Hepatic Estrogen Receptor-alpha mRNA was significantly increased by both exposure concentrations, while Estrogen Receptor-beta transcription was unaltered. The decreased transcription of male-predominant genes supports a demasculinization of testes by EE2 and might reflect reproductive disturbances in the environment.

  • 264.
    Cavallo, Filippo
    et al.
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Limosani, Raffaele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Manzi, Alessandro
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Bonaccorsi, Manuele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Esposito, Raffaele
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Di Rocco, Maurizio
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Teti, Giancarlo
    Robotech Srl, Peccioli, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Dario, Paolo
    BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Development of a socially believable multi-robot solution from town to home2014In: Cognitive Computation, ISSN 1866-9956, E-ISSN 1866-9964, Vol. 6, no 4, 954-967 p.Article in journal (Refereed)
    Abstract [en]

    Technological advances in the robotic and ICT fields represent an effective solution to address specific societal problems to support ageing and independent life. One of the key factors for these technologies is that they have to be socially acceptable and believable to the end-users. This paper aimed to present some technological aspects that have been faced to develop the Robot-Era system, a multi-robotic system that is able to act in a socially believable way in the environments daily inhabited by humans, such as urban areas, buildings and homes. In particular, this paper focuses on two services-shopping delivery and garbage collection-showing preliminary results on experiments conducted with 35 elderly people. The analysis adopts an end-user-oriented perspective, considering some of the main attributes of acceptability: usability, attitude, anxiety, trust and quality of life.

  • 265.
    Cederstedt Johnsson, Linnea
    et al.
    Örebro University, School of Science and Technology.
    Henningsen, David
    Örebro University, School of Science and Technology.
    Konstruktion och optimering av vridhus till kran för virkeshantering2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project concerns the optimization and design of a slewing house for the machine manufacturer K.T.S Production. The slewing house is a technical solution that enables the crane to rotate using pinion and gear racks. This house is meant to be used in future releases of timber cranes which they intend to develop. The core of the problem was to compile a more durable and technologically advanced solution than the previous solutions manufactured by the company. As part of the more technologically advanced solution, rolling bearings have been used in the pinion gear attachment. The problem has been solved by dimensional calculations, comparisons of rolling bearings, material comparisons, modeling, casting adaption and stress analysis. In addition, topology optimization, a method for concept generation, has been used. A slewing house, adapted to the given conditions, has been developed. In this slewing house, tapered roller bearings has been valued as the best solution for the pinion gear attachment. Bearing models, materials and manufacturing methods have been proposed. On that basis, the company is expected to determine whether this concept is to be realized.

  • 266.
    Cehlin, Jesper
    Örebro University, School of Science and Technology.
    FÖRBÄTTRINGSARBETE PÅ BYGGARBETSPLATSER2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wasting is a major problem on construction sites. A concept where the minimization of waste

    is central is called lean manufacturing. This essay aims to investigate how improvement work

    is used on construction sites. The current systems for improvement were analyzed and

    suggestions for improvement were given.

    Interviews were used to examine how improvement work on construction sites was used.

    Self-control and working preparations were used as quality systems on the construction sites.

    It turned out that they have no system for quality improvement. Because no system was used

    a system had to be developed from scratch.

    The PDCA-cycle is a method of improvement which forms the backbone of Lean. This

    method was the basis for the design of the improvement process. The company has

    procedures for the safety work that this improvement work adapted. The result was Quality

    Round which has a similar design as the company's safety and environmental rounds. The

    Quality round is used as health and environmental rounds once a week at the construction site

    where problem areas are identified and then specified in an FMEA-like template. The Quality

    round provides the opportunity to work with the entire PDCA-cycle on construction sites.

    To notice the problems and solving them is one thing, to ensure that the solutions are

    distributed and used is however more difficult. Standardization is a problem at construction

    sites because unlike in the industry business where the production is stationary the facilities

    are constantly moved depending on the projects location. Each project is unique and there is a

    constant exchange of staff and management. Working preparations used in the company

    could serve as method for standardization. The best method is selected and then described in

    detail with the amount of material, equipment, number of workers, etc. In order to add value

    so that even experienced staff will use these, they could also serve as checklists and

    calculation tools.

  • 267. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Giuliani, M. Vittoria
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    The RoboCare project: the user’s view2008In: Aging, disability and independence: selected papers from the 4th international conference on aging, disability and independence / [ed] William C. Mann, IOS Press, 2008, 85-104 p.Chapter in book (Refereed)
  • 268. Cesta, Amedeo
    et al.
    Fratini, Simone
    Oddi, Angelo
    Pecora, Federico
    Örebro University, School of Science and Technology.
    APSI Case# 1: pre-planning science operations in Mars Express2008In: iSAIRAS-08, 2008Conference paper (Refereed)
  • 269. Cesta, Amedeo
    et al.
    Fratini, Simone
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Planning with multiple-components in OMPS2008In: New frontiers in applied artificial intelligence / [ed] Ngoc Thanh Nguyen, Leszek Borzemski, Adam Grzech, Moonis Ali, Springer Berlin/Heidelberg, 2008, 435-445 p.Conference paper (Refereed)
  • 270. Cesta, Amedeo
    et al.
    Fratini, Simone
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Unifying planning and scheduling as timelines in a component-based perspective2008In: Archives of Control Science, ISSN 1230-2384, Vol. 18, no 2, 231-271 p.Article in journal (Refereed)
    Abstract [en]

    The timeline-based approach to planning represents an effective alternative to classical planning for complex domains requiring the use of both temporal reasoning and scheduling features. This paper discusses the constraint-based approach to timeline planning and scheduling introduced in OMPS.  OMPS is a an architecture for problem solving which draws inspiration from both control theory and constraint-based reasoning, and which is based on the notion of components.The rationale behind the component-based approach shares with classical control theory a basic modeling perspective: the planning and scheduling problem is represented by identifying a set of relevant domain components which need to be controlled to obtain a desired temporal behavior for the entire system. Components are entities whose properties may vary in time and which model one or more physical (or logical) domain subsystems relevant to a given planning context. The planner/scheduler plays the role of the controller for these entities, and reasons in terms of constraints that bound their internal evolutions and the desired properties of the generated behaviors (goals). Our work complements this modeling assumption with a constraint-based computational framework.  Admissible temporal behaviors of components are specified as a set of causal constraints within a rich temporal specification, and goals are specified as temporal constraint preferences.  The OMPS software architecture presented in this paper combines both specific and generic constraint solvers in defining consistent timelines which satisfy a given set of goals.

  • 271. Cesta, Amedeo
    et al.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    The robocare project: multi-agent systems for the care of the elderly2003In: ERCIM News, ISSN 0926-4981, no 53Article in journal (Other academic)
  • 272.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Empirical evaluation of human trust in an expressive mobile robot2016In: Proceedings of RSS Workshop "Social Trust in Autonomous Robots 2016", 2016Conference paper (Refereed)
    Abstract [en]

    A mobile robot communicating its intentions using Spatial Augmented Reality (SAR) on the shared floor space makes humans feel safer and more comfortable around the robot. Our previous work [1] and several other works established this fact. We built upon that work by adding an adaptable information and control to the SAR module. An empirical study about how a mobile robot builds trust in humans by communicating its intentions was conducted. A novel way of evaluating that trust is presented and experimentally shown that adaption in SAR module lead to natural interaction and the new evaluation system helped us discover that the comfort levels between human-robot interactions approached those of human-human interactions.

  • 273.
    Chadalavada, Ravi Teja
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    That’s on my Mind!: Robot to Human Intention Communication through on-board Projection on Shared Floor Space2015In: 2015 European Conference on Mobile Robots (ECMR), New York: IEEE conference proceedings , 2015Conference paper (Refereed)
    Abstract [en]

    The upcoming new generation of autonomous vehicles for transporting materials in industrial environments will be more versatile, flexible and efficient than traditional AGVs, which simply follow pre-defined paths. However, freely navigating vehicles can appear unpredictable to human workers and thus cause stress and render joint use of the available space inefficient. Here we address this issue and propose on-board intention projection on the shared floor space for communication from robot to human. We present a research prototype of a robotic fork-lift equipped with a LED projector to visualize internal state information and intents. We describe the projector system and discuss calibration issues. The robot’s ability to communicate its intentions is evaluated in realistic situations where test subjects meet the robotic forklift. The results show that already adding simple information, such as the trajectory and the space to be occupied by the robot in the near future, is able to effectively improve human response to the robot.

  • 274.
    Charusta, Krzysztof
    et al.
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Independent contact regions based on a patch contact model2012In: 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE conference proceedings, 2012, 4162-4169 p.Conference paper (Refereed)
    Abstract [en]

    The synthesis of multi-fingered grasps on nontrivial objects requires a realistic representation of the contact between the fingers of a robotic hand and an object. In this work, we use a patch contact model to approximate the contact between a rigid object and a deformable anthropomorphic finger. This contact model is utilized in the computation of Independent Contact Regions (ICRs) that have been proposed as a way to compensate for shortcomings in the finger positioning accuracy of robotic grasping devices. We extend the ICR algorithm to account for the patch contact model and show the benefits of this solution.

  • 275.
    Charusta, Krzysztof
    et al.
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Dimitrov, Dimitar
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    Generation of independent contact regions on objects reconstructed from noisy real-world range data2012In: 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE conference proceedings, 2012, 1338-1344 p.Conference paper (Refereed)
    Abstract [en]

    The synthesis and evaluation of multi-fingered grasps on complex objects is a challenging problem that has received much attention in the robotics community. Although several promising approaches have been developed, applications to real-world systems are limited to simple objects or gripper configurations. The paradigm of Independent Contact Regions (ICRs) has been proposed as a way to increase the tolerance to grasp positioning errors. This concept is well established, though only on precise geometric object models. This work is concerned with the application of the ICR paradigm to models reconstructed from real-world range data. We propose a method for increasing the robustness of grasp synthesis on uncertain geometric models. The sensitivity of the ICR algorithm to noisy data is evaluated and a filtering approach is proposed to improve the quality of the final result.

  • 276.
    Chatzidaki, Maria D.
    Örebro University, School of Science and Technology.
    Formulation and characterization of W/O nano-dispersions for bioactive delivery applications2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main objective of this study was the formulation of food-grade water-in-oil (W/O) nano-dispersions based mainly on medium or long-chain triglycerides. Two types of dispersions were formulated and structurally compared, namely emulsions and microemulsions. The systems were used as matrices for encapsulating targeted bioactive molecules with specific characteristics such as antioxidants or peptides.

    The structural characterization of the formulated systems was investigated using techniques such as Electron Paramagnetic Resonance (EPR) spectroscopy, Dynamic Light Scattering (DLS), Cryogenic Transmission Electron Microscopy (Cryo-TEM) and Small Angle Xray Scattering (SAXS). The existence of swollen inverse micelles was revealed for the case of microemulsions whereas larger droplets still at the nano-scale were observed for the case of emulsions. Structural differences in the presence of the bioactive molecules or induced by the alteration of components were also observed.

    In order to study the efficacy of the formulations, the proposed loaded systems were assessed either using EPR spectroscopy or Well Diffusion Assay (WDA) depending on the bioactive molecule. It was found that the encapsulated molecules retained their claimed characteristics when encapsulated to the proposed matrices.

    Finally, some of the formulated dispersions were investigated for their behavior under gastrointestinal (GI) conditions. A two-step digestion model using recombinant Dog Gastric Lipase (rDGL) and Porcine Pancreatic Lipase (PPL) was proposed to simulate lipid hydrolysis in humans. The studies revealed significant decrease of the rDGL specific activity in the presence of the microemulsion while in the presence of lower percent of surfactants (case of emulsion) no alterations were observed.

    List of papers
    1. Low shear-rate process to obtain transparent W/O fine emulsions as functional foods
    Open this publication in new window or tab >>Low shear-rate process to obtain transparent W/O fine emulsions as functional foods
    Show others...
    2014 (English)In: Food Research International, ISSN 0963-9969, E-ISSN 1873-7145, Vol. 62, 533-540 p.Article in journal (Refereed) Published
    Abstract [en]

    Edible transparent emulsions of the water-in-oil (W/O) type are highly sought after and currently not available. In such materials, the water droplets can be advantageously used as reservoirs to encapsulate biologically active hydrophilic substances (minerals, antioxidants, etc.). The emulsions must remain transparent, fluid and kinetically stable to meet consumers' requirements. In this paper, we describe a simple yet versatile process to fabricate food grade transparent W/O emulsions. Our method involves the preparation of coarse emulsions which are submitted to shear under laminar flow conditions to reduce their average droplet size. The process generates negligible heat and consequently, it preserves the integrity of thermally sensitive compounds. The obtained emulsions contain between 5 and 10 wt.% of aqueous droplets whose average droplet size is lower than 200 nm. They are kinetically stable for at least 2 months. Transparency results from the relatively low droplet size and the incorporation in the aqueous phase of hydrophilic solutes that decrease the refractive index mismatch between the two immiscible phases.

    Place, publisher, year, edition, pages
    Elsevier, 2014
    Keyword
    W/O nanoemulsion, emulsification, coalescence, Ostwald ripening
    National Category
    Other Chemistry Topics
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-50112 (URN)10.1016/j.foodres.2014.03.069 (DOI)000340015100063 ()2-s2.0-84899521137 (Scopus ID)
    Available from: 2016-05-03 Created: 2016-05-03 Last updated: 2017-10-17Bibliographically approved
    2. Formulation and characterization of food-grade microemulsions as carriers of natural phenolic antioxidants
    Open this publication in new window or tab >>Formulation and characterization of food-grade microemulsions as carriers of natural phenolic antioxidants
    Show others...
    2015 (English)In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, E-ISSN 1873-4359, Vol. 483, 130-136 p.Article in journal (Refereed) Published
    Abstract [en]

    Food-grade W/O microemulsions based on lecithin, caprylic/capric triglycerides, isopropyl myristate, alcohols and water were formulated and structurally characterized to be used as potential carriers of natural food antioxidants. Different well-known food antioxidants including gallic acid, p-hydroxybenzoic acid, protocatechuic acid and tyrosol were successfully encapsulated in the aqueous cores of the microemulsions. A pseudo-ternary phase diagram was constructed to determine the extent of the monophasic area that corresponds to an inverted type microemulsion. Apparent hydrodynamic diameter measurements of empty and loaded microemulsions were performed using dynamic light scattering (DLS) and swollen micelles with diameters smaller than 10 nm were detected. Interfacial properties of the microemulsions were studied by electron paramagnetic resonance (EPR) spectroscopy employing the nitroxide spin probe 5-doxylstearic acid (5-DSA). A small increase in spin probe mobility upon addition of the antioxidants was observed; whereas the rigidity of the surfactants was not affected. Cryogenic transmission electron microscopy (Cryo-TEM) indicated the existence of entangled thread-like reversed micelles. Finally, the investigated phenolics were assessed and compared for their radical scavenging activity using an EPR approach based on free radicals. The encapsulated gallic acid showed the highest antioxidant activity (0.93 mM trolox equivalents) as compared to other antioxidants assessed within the frame of this study.

    Place, publisher, year, edition, pages
    Elsevier, 2015
    Keyword
    W/O microemulsion, Gallic acid, Antioxidant, EPR, DLS, Cryo-TEM
    National Category
    Other Chemistry Topics
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-50111 (URN)10.1016/j.colsurfa.2015.03.060 (DOI)000362146200017 ()2-s2.0-84941745179 (Scopus ID)
    Available from: 2016-05-03 Created: 2016-05-03 Last updated: 2017-10-18Bibliographically approved
    3. Microemulsion versus emulsion as effective carrier of hydroxytyrosol
    Open this publication in new window or tab >>Microemulsion versus emulsion as effective carrier of hydroxytyrosol
    Show others...
    2016 (English)In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 137, no 1, 146-151 p.Article in journal (Refereed) Published
    Abstract [en]

    Two edible Water-in-Oil (W/O) dispersions, an emulsion that remains kinetically stable and a microemulsion which is spontaneously formed, transparent and thermodynamically stable, were developed for potential use as functional foods, due to their ability to be considered as matrices to encapsulate biologically active hydrophilic molecules. Both systems contained Medium Chain Triglycerides (MCT) as the continuous phase and were used as carriers of Hydroxytyrosol (HT), a hydrophilic antioxidant of olive oil. A low energy input fabrication process of the emulsion was implemented. The obtained emulsion contained 1.3% (w/w) of surfactants and 5% (w/w) aqueous phase. The spontaneously formed microemulsion contained 4.9% (w/w) of surfactants and 2% (w/w) aqueous phase. A comparative study in terms of structural characterization of the systems in the absence and presence of HT was carried out. Particle size distribution obtained by Dynamic Light Scattering (DLS) technique and interfacial properties of the surfactants' layer, examined by Electron Paramagnetic Resonance (EPR) spectroscopy indicated the involvement of HT in the surfactant membrane. Finally, the proposed systems were studied for the scavenging activity of the encapsulated antioxidant toward galvinoxyl stable free radical showing a high scavenging activity of HT in both systems.

    Place, publisher, year, edition, pages
    Elsevier, 2016
    Keyword
    Emulsion, Microemulsion, Hydroxytyrosol, DLS, EPR, Antioxidant activity
    National Category
    Other Chemistry Topics
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-50110 (URN)10.1016/j.colsurfb.2015.04.053 (DOI)000367491200017 ()25999235 (PubMedID)2-s2.0-84951573458 (Scopus ID)
    Available from: 2016-05-03 Created: 2016-05-03 Last updated: 2017-10-17Bibliographically approved
    4. Microemulsions as potential carriers of nisin: effect of composition on the structure and efficacy
    Open this publication in new window or tab >>Microemulsions as potential carriers of nisin: effect of composition on the structure and efficacy
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-50113 (URN)
    Available from: 2016-05-04 Created: 2016-05-03 Last updated: 2017-10-17Bibliographically approved
    5. Water-in-Oil microemulsions versus emulsions as carriers of hydroxytyrosol: an in vitro gastrointestinal lipolysis study using the pHstat technique
    Open this publication in new window or tab >>Water-in-Oil microemulsions versus emulsions as carriers of hydroxytyrosol: an in vitro gastrointestinal lipolysis study using the pHstat technique
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-50119 (URN)
    Available from: 2016-05-04 Created: 2016-05-03 Last updated: 2017-10-17Bibliographically approved
  • 277.
    Chatzidaki, Maria D.
    et al.
    Örebro University, School of Science and Technology. Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece.
    Arik, Nehir
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece..
    Monteil, Julien
    Univ Bordeaux, CBMN, Lab Chim & Biol Membranes & Nanoobjets, Bordeaux, France..
    Papadimitriou, Vassiliki
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece..
    Leal-Calderon, Fernando
    Univ Bordeaux, CBMN, Lab Chim & Biol Membranes & Nanoobjets, Bordeaux, France..
    Xenakis, Aristotelis
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece.;Univ Orebro, Sch Sci & Technol, MTM Res Ctr, S-31705 Orebro, Sweden..
    Microemulsion versus emulsion as effective carrier of hydroxytyrosol2016In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 137, no 1, 146-151 p.Article in journal (Refereed)
    Abstract [en]

    Two edible Water-in-Oil (W/O) dispersions, an emulsion that remains kinetically stable and a microemulsion which is spontaneously formed, transparent and thermodynamically stable, were developed for potential use as functional foods, due to their ability to be considered as matrices to encapsulate biologically active hydrophilic molecules. Both systems contained Medium Chain Triglycerides (MCT) as the continuous phase and were used as carriers of Hydroxytyrosol (HT), a hydrophilic antioxidant of olive oil. A low energy input fabrication process of the emulsion was implemented. The obtained emulsion contained 1.3% (w/w) of surfactants and 5% (w/w) aqueous phase. The spontaneously formed microemulsion contained 4.9% (w/w) of surfactants and 2% (w/w) aqueous phase. A comparative study in terms of structural characterization of the systems in the absence and presence of HT was carried out. Particle size distribution obtained by Dynamic Light Scattering (DLS) technique and interfacial properties of the surfactants' layer, examined by Electron Paramagnetic Resonance (EPR) spectroscopy indicated the involvement of HT in the surfactant membrane. Finally, the proposed systems were studied for the scavenging activity of the encapsulated antioxidant toward galvinoxyl stable free radical showing a high scavenging activity of HT in both systems.

  • 278.
    Chatzidaki, Maria D.
    et al.
    Örebro University, School of Science and Technology. National Hellenic Research Foundation Institute of Biology Medicinal Chemistry and Biotechnology.
    Eduardo, Mateos-Diaz
    CNRS, UMR7282 Enzymologie Interfaciale et Physiologie de la Lipolyse.
    Leal-Calderon, Fernando
    Polytechnic Institute of Bourdeaux, CBMN.
    Xenakis, Aristotelis
    National Hellenic Research Foundation Institute of Biology Medicinal Chemistry and Biotechnology.
    Carrière, Frédéric
    CNRS, UMR7282 Enzymology at Interfaces and Physiology of Lipolysis.
    Water-in-Oil microemulsions versus emulsions as carriers of hydroxytyrosol: an in vitro gastrointestinal lipolysis study using the pHstat techniqueManuscript (preprint) (Other academic)
  • 279.
    Chatzidaki, Maria D.
    et al.
    Örebro University, School of Science and Technology. Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece.
    Mitsou, Evgenia
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece..
    Yaghmur, Anan
    Univ Copenhagen, Fac Hlth & Med Sci, Dept Pharm, DK-1168 Copenhagen, Denmark..
    Xenakis, Aristotelis
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece.;Univ Orebro, Sch Sci & Technol, MTM Res Ctr, Orebro, 31705, Sweden..
    Papadimitriou, Vassiliki
    Natl Hellen Res Fdn, Inst Biol Med Chem & Biotechnol, Athens 11635, Greece..
    Formulation and characterization of food-grade microemulsions as carriers of natural phenolic antioxidants2015In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, E-ISSN 1873-4359, Vol. 483, 130-136 p.Article in journal (Refereed)
    Abstract [en]

    Food-grade W/O microemulsions based on lecithin, caprylic/capric triglycerides, isopropyl myristate, alcohols and water were formulated and structurally characterized to be used as potential carriers of natural food antioxidants. Different well-known food antioxidants including gallic acid, p-hydroxybenzoic acid, protocatechuic acid and tyrosol were successfully encapsulated in the aqueous cores of the microemulsions. A pseudo-ternary phase diagram was constructed to determine the extent of the monophasic area that corresponds to an inverted type microemulsion. Apparent hydrodynamic diameter measurements of empty and loaded microemulsions were performed using dynamic light scattering (DLS) and swollen micelles with diameters smaller than 10 nm were detected. Interfacial properties of the microemulsions were studied by electron paramagnetic resonance (EPR) spectroscopy employing the nitroxide spin probe 5-doxylstearic acid (5-DSA). A small increase in spin probe mobility upon addition of the antioxidants was observed; whereas the rigidity of the surfactants was not affected. Cryogenic transmission electron microscopy (Cryo-TEM) indicated the existence of entangled thread-like reversed micelles. Finally, the investigated phenolics were assessed and compared for their radical scavenging activity using an EPR approach based on free radicals. The encapsulated gallic acid showed the highest antioxidant activity (0.93 mM trolox equivalents) as compared to other antioxidants assessed within the frame of this study.

  • 280.
    Chatzidaki, Maria D.
    et al.
    Örebro University, School of Science and Technology. Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Papadimitriou, Konstantinos
    Agricultural University of Athens.
    Alexandraki, Voula
    Agricultural University of Athens.
    Tsirvouli, Eirini
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Chakim, Zena
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Ghazal, Aghiad
    University of Copenhagen, Denmark.
    Mortensen, Kell
    University of Copenhagen, Denmark.
    Yaghmur, Anan
    University of Copenhagen, Denmark.
    Salentinig, Stefan
    Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.
    Papadimitriou, Vassiliki
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Tsakalidou, Effie
    Agricultural University of Athens.
    Xenakis, Aristotelis
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece; Örebro University, Sweden .
    Microemulsions as potential carriers of nisin: effect of composition on the structure and efficacyManuscript (preprint) (Other academic)
  • 281.
    Chen, Zetao
    et al.
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Lowry, Stephanie
    Örebro University, School of Science and Technology.
    Jacobson, Adam
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Ge, ZongYuan
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Milford, Michael
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Distance metric learning for feature-agnostic place recognition2015In: Proceedings of the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2015, 2556-2563 p.Conference paper (Refereed)
    Abstract [en]

    The recent focus on performing visual navigation and place recognition in changing environments has resulted in a large number of heterogeneous techniques each utilizing their own learnt or hand crafted visual features. This paper presents a generally applicable method for learning the appropriate distance metric by which to compare feature responses from any of these techniques in order to perform place recognition under changing environmental conditions. We implement an approach which learns to cluster images captured at spatially proximal locations under different conditions, separated from frames captured at different places. The formulation is a convex optimization, guaranteeing the existence of a global solution. We evaluate the general applicability of our method on two benchmark change datasets using three typical image pre-processing and feature types: GIST, Principal Component Analysis and learnt Convolutional Neural Network features. The results demonstrate that the distance metric learning approach uniformly improves single-image-based visual place recognition performance across all feature types. Furthermore, we demonstrate that this performance improvement is maintained when the sequence-based algorithm SeqSLAM is applied to the single-image place recognition results, leading to state-of-the-art performance.

  • 282.
    Cheng, Xiaoliang
    et al.
    Department of Mathematics, Zhejiang University, Hangzhou, Zhejiang, China.
    Lin, Guangliang
    Department of Mathematics, Zhejiang University, Hangzhou, Zhejiang, China.
    Zhang, Ye
    Örebro University, School of Science and Technology. Department of Mathematics.
    Gong, Rongfang
    Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing, China.
    Gulliksson, Mårten
    Örebro University, School of Science and Technology. Department of Mathematics.
    A modified coupled complex boundary method for an inverse chromatography problem2017In: Journal of Inverse and Ill-Posed Problems, ISSN 0928-0219, E-ISSN 1569-3945Article in journal (Refereed)
    Abstract [en]

    Adsorption isotherms are the most important parameters in rigorous models of chromatographic processes. In this paper, in order to recover adsorption isotherms, we consider a coupled complex boundary method (CCBM), which was previously proposed for solving an inverse source problem [2]. With CCBM, the original boundary fitting problem is transferred to a domain fitting problem. Thus, this method has advantages regarding robustness and computation in reconstruction. In contrast to the traditional CCBM, for the sake of the reduction of computational complexity and computational cost, the recovered adsorption isotherm only corresponds to the real part of the solution of a forward complex initial boundary value problem. Furthermore, we take into account the position of the profiles and apply the momentum criterion to improve the optimization progress. Using Tikhonov regularization, the well-posedness, convergence properties and regularization parameter selection methods are studied. Based on an adjoint technique, we derive the exact Jacobian of the objective function and give an algorithm to reconstruct the adsorption isotherm. Finally, numerical simulations are given to show the feasibility and efficiency of the proposed regularization method.

  • 283.
    Chennaya, Veronica
    Örebro University, School of Science and Technology.
    Correlation between Environmental Pollutants and Neuropsychological Disorders2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Environmental pollutants are all around us. How are they affecting human brains? My hypothesis is that there is a correlation between these widespread chemicals and neuropsychological disorders. I have read and written about four disorders; autism spectrum disorder, attention deficit hyperactivity disorder, schizophrenia and bipolar disorder which I have tried to correlate to environmental pollutants; metals, endocrine disrupting chemicals, pesticides and air pollutants through literature (through searching Google Scholar and PubMed). Most research found supports my hypothesis of a correlation between pollutants and neuropsychological disorders both in epidemiological studies as well as studies conducted on humans. Additionally there are animal studies that show correlation between different chemicals found in nature and traits or symptoms characteristic for a certain disorder. The findings show correlation but also raise other questions such as; what role do additional aspects play, such as social and demographic influences? What is the reason of the skewed gender bias towards the male sex in autism spectrum disorder and attention deficit hyperactivity disorder? 

  • 284.
    Christensson, Johan
    et al.
    Örebro University, School of Science and Technology.
    Gustafsson, Ludwig
    Örebro University, School of Science and Technology.
    Utveckling av geometrisk reverse engineering med 3D-skanningsutrustning2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D scanning technology has had enormous growth in the last 10 years.[1] The 3D scanning solutions on the market today can create digital copies of a physical shape in minutes, with a precision of about 40 µm [1]. This makes the 3D scanner an effective and tolerance-proof solution for applications including; Quality insurance, Aftermarket parts, Aesthetic limb manufacturing and Reverse engineering.

    Reverse engineering is a mechanical construction method where the engineer uses a, so called, "Top-down" methodology. The method consists of getting basic understanding about an unknown product by disassembling it.

    Geometric reverse engineering, on the other hand, shares the basic values of reverse engineering, but instead of getting a better understanding of the components in a product, the objective is to create usable CAD-files from a physical object.

    In the case of geometric reverse engineering and 3D scanning equipment at Volvos model construction department, it is very important to create a fully functional model of the object, where all measures and parameters that might need changing (for casting optimization), can be changed in an easy fashion. It is also important for the model to have a high tolerance level and low surface roughness.

    This thesis main focus is to develop a time efficient method of working with 3D scanners and geometric reverse engineering for Volvo GTO.

  • 285.
    Cicek, Mehmet
    Örebro University, School of Science and Technology.
    Universell Hjuladapter2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis has been carried out in collaboration with JOSAM in Örebro, which is a leading company in the trend and wheel alignment on commercial vehicles. The company was founded in 1972 and has manufactured equipment for 40 years.

     

    The thesis is about the wheel adapter problems to be fixed to aluminum rims.

     

    The result was a solution proposed for a wheel adapter, which works the same for aluminum and steel wheels. It has the flexibility to meet the 15-inch up to 24-inch rims.

  • 286.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Planning in inhabited environments: human-aware task planning and activity recognition2011In: Künstliche Intelligenz, ISSN 0933-1875, Vol. 25, no 4, 355-358 p.Article in journal (Refereed)
    Abstract [en]

    Our work addresses issues related to the cohabitation of service robots and people in unstructured environments. We propose new planning techniques to empower robot means-end reasoning with the capability of taking into account human intentions and preferences. We also address the problem of human activity recognition in instrumented environments. We employ a constraint-based approach to realize a continuous inference process to attach a meaning to sensor traces as detected by sensors distributed in the environment.

  • 287.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Human-aware planning for robots embedded in ambient ecologies2012In: Pervasive and Mobile Computing, ISSN 1574-1192, E-ISSN 1873-1589, Vol. 8, no 4, 542-561 p.Article in journal (Refereed)
    Abstract [en]

    We address the issue of human-robot cohabitation in smart environments. In particular, the presence of humans in a robot's work space has a profound influence on how the latter should plan its actions. We propose the use of Human-Aware Planning, an approach in which the robot exploits the capabilities of a sensor-rich environment to obtain information about the (current and future) activities of the people in the environment, and plans its tasks accordingly.

    Here, we formally describe the planning problem behind our approach, we analyze its complexity and we detail the algorithm of our planner. We then show two application scenarios that could benefit from the techniques described. The first scenario illustrates the applicability of human-aware planning in a domestic setting, while the second one illustrates its use for a robotic helper in a hospital. Finally, we present a five hour-long test run in a smart home equipped with real sensors, where a cleaning robot has been deployed and where a human subject is acting. This test run in a real setting is meant to demonstrate the feasibility of our approach to human-robot interaction.

  • 288.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Uras, Tansel
    Department of Computer Science, University of Southern California, USA.
    Koenig, Sven
    Department of Computer Science, University of Southern California, USA.
    Integrated Motion Planning and Coordination for Industrial Vehicles2014In: Proceedings of the 24th International Conference on Automated Planning and Scheduling, 2014Conference paper (Refereed)
    Abstract [en]

    A growing interest in the industrial sector for autonomous ground vehicles has prompted significant investment in fleet management systems. Such systems need to accommodate on-line externally imposed temporal and spatial requirements, and to adhere to them even in the presence of contingencies. Moreover, a fleet management system should ensure correctness, i.e., refuse to commit to requirements that cannot be satisfied. We present an approach to obtain sets of alternative execution patterns (called trajectory envelopes) which provide these guarantees. The approach relies on a constraint-based representation shared among multiple solvers, each of which progressively refines trajectory envelopes following a least commitment principle.

  • 289.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Uras, Tansel
    Department of Computer Science, University of Southern California, USA.
    Koenig, Sven
    Department of Computer Science, University of Southern California, USA.
    A lattice-based approach to multi-robot motion planning for non-holonomic vehicles2014In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems, 2014, 232-239 p.Conference paper (Refereed)
    Abstract [en]

    Coordinating fleets of autonomous, non-holonomic vehicles is paramount to many industrial applications. While there exists solutions to efficiently calculate trajectories for individual vehicles, an effective methodology to coordinate their motions and to avoid deadlocks is still missing. Decoupled approaches, where motions are calculated independently for each vehicle and then centrally coordinated for execution, have the means to identify deadlocks, but not to solve all of them. We present a novel approach that overcomes this limitation and that can be used to complement the deficiencies of decoupled solutions with centralized coordination. Here, we formally define an extension of the framework of lattice-based motion planning to multi-robot systems and we validate it experimentally. Our approach can jointly plan for multiple vehicles and it generates kinematically feasible and deadlock-free motions.

  • 290.
    Claesson, Anna
    Örebro University, School of Science and Technology.
    Fytoremediering av jordbruksmark med annuell solros (Helianthus annuus peredovic)2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inledning: Metaller är ämnen som förkommer naturligt i vår miljö men kan också spridas via t. ex. industrier. Många metaller kan vara skadliga för djur och natur. Metallföroreningar ökar idag i vår omgivning samt i åkermarken. Den ökande halten metaller i jordbruksmark ställer till problem då grödor ackumulerar de hälsofarliga ämnena i sin biomassa vilket riskerar konsumentens hälsa. Exponeringen av metaller har visat sig vara kopplade till flera sjukdomar. Det finns flera olika metoder för sanering av metallförorenade områden, en miljövänlig saneringsmetod är fytoremediering. Att fytoremediera mark innebär sanering, återställning eller stabilisering av ett område med hjälp av vegetation. Ett exempel på en beprövad gröda som visat en effektiv metallackumulation är Helianthus annuus (solros). Syfte: Att mäta och analysera metallinnehåll i åkermark samt undersöka den annuella solrosen Helianthus annuus peredovic förmåga att ackumulera metaller från mark. Metod och material: Odlingsförsök av H. annuus p. i jord från åkermark samt metallanalys på jord innan sådd och efter skörd. Plantor skördades vid två tillfällen för metallanalys. Resultat: H. annuus p. visade effektiv ackumulation av 16 metaller i grönmassa. Slutsats: H.annuus p. är en effektiv ackumulerade av många metaller och således en möjlig gröda att använda vid fytoremediering av åkermark.

  • 291.
    Clefjord Ljungberg, Hanna
    et al.
    Örebro University, School of Science and Technology.
    Brunzell, Malin
    Örebro University, School of Science and Technology.
    Analys av inköpsbeteende av underleverantörer2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 292. Clemmensen, K. E.
    et al.
    Bahr, A.
    Ovaskainen, O.
    Dahlberg, A.
    Ekblad, Alf
    Örebro University, School of Science and Technology.
    Wallander, H.
    Stenlid, J.
    Finlay, R. D.
    Wardle, D. A.
    Lindahl, B. D.
    Roots and associated fungi drive long-term carbon sequestration in boreal forest2013In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 339, no 6127, 1615-1618 p.Article in journal (Refereed)
    Abstract [en]

    Boreal forest soils function as a terrestrial net sink in the global carbon cycle. The prevailing dogma has focused on aboveground plant litter as a principal source of soil organic matter. Using C-14 bomb-carbon modeling, we show that 50 to 70% of stored carbon in a chronosequence of boreal forested islands derives from roots and root-associated microorganisms. Fungal biomarkers indicate impaired degradation and preservation of fungal residues in late successional forests. Furthermore, 454 pyrosequencing of molecular barcodes, in conjunction with stable isotope analyses, highlights root-associated fungi as important regulators of ecosystem carbon dynamics. Our results suggest an alternative mechanism for the accumulation of organic matter in boreal forests during succession in the long-term absence of disturbance.

  • 293.
    Comont, David
    et al.
    Aberystwyth University.
    Albert, Andreas
    Helmholtz Zentrum München.
    Aphalo, Pedro
    Helsingfors universitet.
    Gabersick, Alenka
    University of Ljubljana.
    Hauser, Marie Teres
    University of Natural Resources and Life Sciences - Vienna.
    Jansen, Marcel
    University College of Cork.
    Robson, Matthew
    Helsingfors universitet.
    Schreiner, Monika
    Leibniz-Institute of Vegetable and Ornamental Plants - Großbeeren, Germany.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Gwynn-Jones, Dylan
    Aberystwyth University.
    Exploring latitudinal variation in UV radiation and climate: impacts on a model grass system2011In: Abstracts of the 1st Annual Meeting of COST Action FA0906 UV4growth, Szeged: Biological Research Center of the Hungarian Academy of Sciences , 2011, 14-14 p.Conference paper (Refereed)
    Abstract [en]

    Perennial ryegrass (Lolium perenne) seedlings were grown at 14 European locations across a latitudinal gradient spanning 37 to 68°N. Seedlings planted in nutrient enriched vermiculite were grown outdoors over five weeks between the 29th June and the 3rd August 2010. At each location there were three treatments – open, filtered with cellulose acetate (UV transparent) and filtered with Mylar (UV opaque). Plants were regularly watered and outdoor climatic conditions were monitored at nearby meteorological stations. The aim of the experiment was to assess the significance of ambient UV radiation to L.perenne, both at each location and across the gradient in terms of aboveground biomass, tiller number, and the level of UV protective plant pigments. Material was further screened using metabolite fingerprinting (FT-IR spectroscopy) to assess local, regional and latitudinal variation in total plant chemistry. Data presented will explore and interpret the complex variations in growth and chemistry looking at local responses and the latitudinal gradient explored.

  • 294.
    Comont, David
    et al.
    Aberystwyth University.
    Martinez Abaigar, Javier
    University of La Rioja.
    Albert, Andreas
    Helmholtz Zentrum München.
    Aphalo, Pedro
    Helsingfors universitet.
    Causton, David R
    Aberystwyth University.
    López Figueroa, Félix
    University of Málaga.
    Gaberscik, Alenka
    University of Ljubljana.
    Llorens, Laura
    University of Girona.
    Hauser, Marie-Theres
    University of Natural Resulrces and Life Sciences-BOKU, Wien.
    Jansen, Marcel A K
    University College Cork.
    Kardefelt, Majlis
    Abisko forskningsstation.
    de la Coba Luque, Paqui
    University of Málaga.
    Neubert, Susanne
    University of Natural Resulrces and Life Sciences-BOKU, Wien.
    Núnez-Olivera, Encarnación
    University of La Rioja.
    Olsen, Jorunn
    Norwegian University of Life Sciences.
    Robson, Matthew
    Helsingfors universitet.
    Schreiner, Monika
    Leibniz-Institute of Vegetable and Ornamental Crops - Großbeeren.
    Sommaruga, Ruben
    University of Innsbruck.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Torre, Sissel
    Norwegian University of Life Sciences.
    Turunen, Minna
    University of Lapland.
    Veljovic-Jovanovic, Sonja
    Institute for Multidisciplinary Research - Belgrade.
    Verdaguer, Dolors
    University of Girona.
    Vidovic, Marija
    Institute for Multidisciplinary Research - Belgrade.
    Wagner, Johanna
    University of Innsbruck.
    Winkler, Jana Barbro
    Helmholtz Zentrum München.
    Zipoli, Gaetano
    C.N.R. Ibimet - Firenze.
    Gwynn-Jones, Dylan
    University of Aberystwyth.
    UV responses of Lolium perenne raised along a latitudinal gradient across Europe: a filtration study2012In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 145, 604-618 p.Article in journal (Refereed)
    Abstract [en]

    Lolium perenne (cv. AberDart) was grown at 14 locations along a latitudinal gradient across Europe (37–68◦N) to study the impact of ultraviolet radiation (UV) and climate on aboveground growth and foliar UV-B absorbing compounds. At each location, plants were grown outdoors for 5 weeks in a replicated UV-B filtration experiment consisting of open, UV-B transparent (cellulose diacetate) and UV-B opaque (polyester) environments. Fourier transform-infrared spectroscopy was used to compare plantmetabolite profiles in relation to treatment and location. UV radiation and climatic parameters were determined for each location from online sources and the data were assessed using a combination of ANOVA and multiple regression analyses. Most of the variation in growth between the locations was attributable to the combination of climatic parameters, with minimum temperature identified as an important growth constraint. However, no single environmental parameter could consistently account for the variability in plant growth. Concentrations of foliar UV-B absorbing compounds showed a positive trend with solar UV across the latitudinal gradient; however, this relationship was not consistent in all treatments. The most striking experimental outcome from this study was the effect of presence or absence of filtration frames onUV-absorbing compounds. Overall, the study demonstrates the value of an European approach in studying the impacts of natural UV across a large latitudinal gradient. We have shown the feasibility of coordinated UV filtration at multiple sites but have also highlighted the need for open controls and careful interpretation of plant responses.

  • 295.
    Conti, Mauro
    et al.
    Department of Mathematics, University of Padua, Padua, Italy.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark.
    Lesyk, Viktor
    DTU Compute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark; Centre for Applied Autonomous Sensor Systems (AASS), Örebro University, Örebro, Sweden.
    A Survey of Man In The Middle Attacks2016In: IEEE Communications Surveys and Tutorials, ISSN 1553-877X, E-ISSN 1553-877X, Vol. 18, no 3, 2027-2051 p.Article in journal (Refereed)
    Abstract [en]

    The Man-In-The-Middle (MITM) attack is one of the most well known attacks in computer security, representing one of the biggest concerns for security professionals. MITM targets the actual data that flows between endpoints, and the confidentiality and integrity of the data itself. In this paper, we extensively review the literature on MITM to analyse and categorize the scope of MITM attacks, considering both a reference model, such as the open systems interconnection (OSI) model, as well as two specific widely used network technologies, i.e., GSM and UMTS. In particular, we classify MITM attacks based on several parameters, like location of an attacker in the network, nature of a communication channel, and impersonation techniques. Based on an impersonation techniques classification, we then provide execution steps for each MITM class. We survey existing countermeasures and discuss the comparison among them. Finally, based on our analysis, we propose a categorisation of MITM prevention mechanisms, and we identify some possible directions for future research.

  • 296.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Cesta, Amadeo
    CNR, Italy.
    Cortellessa, Gabriella
    CNR, Italy.
    Coraci, Luca
    CNR, Italy.
    Gonzalez, Javier
    Malaga University.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Furfari, Francesco
    CNR, Italy.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Orlandini, Andrea
    CNR, Italy.
    Palumbo, Filippo
    CNR, Italy.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    von Rump, Stephan
    Giraff AB.
    Ullberg, Jonas
    Örebro University, School of Science and Technology.
    Östlund, Britt
    Lund University, Lund, Sweden.
    GiraffPlus: combining social interaction and long term monitoring for promoting independent living2013In: 2013 6TH INTERNATIONAL CONFERENCE ON HUMAN SYSTEM INTERACTIONS (HSI), New York, 2013, 578-585 p.Conference paper (Refereed)
    Abstract [en]

    Early detection and adaptive support to changing individual needs related to ageing is an important challenge in today’s society. In this paper we present a system called GiraffPlus that aims at addressing such a challenge and is developed in an on-going European project. The system consists of a network of home sensors that can be automatically configured to collect data for a range of monitoring services; a semi-autonomous telepresence robot; a sophisticated context recognition system that can give high-level and long term interpretations of the collected data and respond to certain events; and personalized services delivered through adaptive user interfaces for primary users. The system performs a range of services including data collection and analysis of long term trends in behaviors and physiological parameters (e.g. relating to sleep or daily activity); warnings, alarms and reminders; and social interaction through the telepresence robot. The latter is based on the Giraff telepresence robot, which is already in place in a number of homes. Particular emphasis is put on user evaluation outside the laboratories. A distinctive aspect of the project is that the GiraffPlus system will be installed and evaluated in at least 15 homes of elderly people. The concept of “useworthiness” is central in order to assure that the GiraffPlus system provides services that are easy to use and worth using. In addition, by using existing and affordable components we strive to achieve a system that is affordable and close to commercialization.

  • 297.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Cortellessa, GabriellaKristoffersson, AnnicaÖrebro University, School of Science and Technology.Loutfi, AmyÖrebro University, School of Science and Technology.
    Proceedings of the Ro-man 2012 Workshop on Social Robotics Telepresence2012Conference proceedings (editor) (Other academic)
  • 298.
    Coradeschi, Silvia
    et al.
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Cortellessa, GabriellaCNR - National Research Council of Italy, Istituto di Scienze e Tecnologie della Cognizione, Rome, Italy.Kristoffersson, AnnicaÖrebro University, School of Science and Technology.Loutfi, AmyÖrebro University, School of Science and Technology.Severinson Eklundh, KerstinCI Group, CSC, KTH Royal Institute of Technology, Stockholm, Sweden.
    Proceedings of the 2011 HRI Workshop on Social Robotic Telepresence2011Conference proceedings (editor) (Other academic)
  • 299.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Von Rump, Stephen
    Cesta, Amedeo
    Cortellessa, Gabriella
    Gonzalez, Javier
    Towards a methodology for longitudinal evaluation of social robotic telepresence for elderly2011In: 1st Workshop on Social Robotic Telepresence at HRI 2011, 2011Conference paper (Refereed)
    Abstract [en]

    This paper describes a methodology for performing longitudinal evaluations when a social robotic telepresence system is deployed in realistic environments. This work is the core of an Ambient Assisted Living Project called ExCITE, Enabling Social Interaction Through Telepresence. The ExCITE project is geared towards an elderly audience and has as aim to increase social interaction among elderly, their family and healthcare services by using robotic telepresence. The robotic system used in the project is called the Giraff robot and over a three year period, prototypes of this platform are deployed at a number of test-sites in different European countries where user feedback is collected and fedback into the refinement of the prototype. In this paper, we discuss the methodology of ExCITE in particular relation to other methodologies for longitudinal evaluation. The paper also provides a discussion of the possible pitfalls and risks in performing longitudinal studies of this nature particularly as they relate to social robotic telepresence technologies.

  • 300.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Wrede, Britta
    Bielefeld University.
    A short review of symbol grounding in robotic and intelligent systems2013In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 27, no 2, 129-136 p.Article in journal (Refereed)
    Abstract [en]

    This paper gives an overview of the research papers published in Symbol Grounding in the period from the beginning of the 21st century up 2012. The focus is in the use of symbol grounding for robotics and intelligent system. The review covers a number of subtopics, that include, physical symbol grounding, social symbol grounding, symbol grounding for vision systems, anchoring in robotic systems, and learning symbol grounding in software systems and robotics. This review is published in conjunction with a special issue on Symbol Grounding in the Künstliche Intelligenz Journal.

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