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  • 1.
    Aaboen, Lise
    et al.
    Department of Industrial Economics and Technology Management, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
    Fredriksson, Anna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    The relationship development aspect of production transfer2016In: Journal of Purchasing and Supply Management, ISSN 1478-4092, E-ISSN 1873-6505, Vol. 22, no 1, p. 53-65Article in journal (Refereed)
    Abstract [en]

    Production transfers are a result of outsourcing and offshoring decisions. Because of the strategic focus of the outsourcing literature, the operational issues of relationship development between sender and receiver and its impact on the transfer progress have not been fully depicted. The purpose of the present paper is to explore relationship development during production transfer. To fulfil this purpose, we studied three different production transfers and derived four propositions for further testing. Our main conclusions included that dependence and power gradually shift between the sender and the receiver and that the relationship between them sets the arena for what types of relationships can be developed between the receiver and the suppliers. Furthermore, short social distances can bridge cultural and technological distances to some extent, because it motivates the actors to bring their relationship into a more developed state. Finally, we noticed that the headquarters’ involvement can work both as an inhibitor as well as a converter.

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  • 2.
    Aaboen, Lise
    et al.
    Norwegian University of Science and Technology (NTNU), Norway.
    Haneberg, Dag Håkon
    Norwegian University of Science and Technology (NTNU), Norway.
    Jakobsen, Siri
    Nord University Business School, Nord University, Norway.
    Lauvås, Thomas
    Nord University Business School, Nord University, Norway.
    Wigger, Karin
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering. Nord University Business School, Nord University, Norway.
    Case-based entrepreneurship education in and for the Nordic region2022In: Reframing the Case Method in Entrepreneurship Education.: Cases from the Nordic Countries / [ed] Wigger, K., Aaboen, L., Haneberg, D.H.,Jakobsen, S., & Lauvås, T., Edward Elgar Publishing, 2022, p. 2-17Chapter in book (Refereed)
    Abstract [en]

    The case method provides entrepreneurship educators with great potential to be entrepreneurial and to think outside the box when adjusting the case method for increased entrepreneurial learning. This chapter provides the theoretical background of case-based entrepreneurship education and a debate on context in case teaching in general and the Nordic countries in particular. Further the chapter provides a synopsis and reflections of how the chapters in this book discuss the design and utilization of cases through 2 parts. Part 1 includes theoretical perspectives, discussions, and practical procedures on how the case method and case activities can be reframed and approached in entrepreneurship education in general and for experiential learning in particular. Part 2 contributes with a collection of Nordic entrepreneurship cases with accompanying teaching notes. We believe that this book is of great inspiration for entrepreneurship educators wanting to use the case method in their teaching.

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  • 3.
    Aaro, Gustav
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Roos, Daniel
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Carlsson, Niklas
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Toolset for Run-time Dataset Collection of Deep-scene Information2020In: Symposium on Modelling, Analysis, and Simulation of Computer and Telecommunication Systems (MASCOTS), Springer, 2020, p. 224-236Conference paper (Refereed)
    Abstract [en]

    Virtual reality (VR) provides many exciting new application opportunities, but also present new challenges. In contrast to 360° videos that only allow a user to select its viewing direction, in fully immersive VR, users can also move around and interact with objects in the virtual world. To most effectively deliver such services it is therefore important to understand how users move around in relation to such objects. In this paper, we present a methodology and software tool for generating run-time datasets capturing a user’s interactions with such 3D environments, evaluate and compare different object identification methods that we implement within the tool, and use datasets collected with the tool to demonstrate example uses. The tool was developed in Unity, easily integrates with existing Unity applications through the use of periodic calls that extracts information about the environment using different ray-casting methods. The software tool and example datasets are made available with this paper. 

  • 4.
    Aarts, B.
    et al.
    Netherlands Forensic Institute, Biological Traces and DNA, The Hague, Netherlands.
    Kokshoorn, B.
    Netherlands Forensic Institute, Biological Traces and DNA, The Hague, Netherlands.
    Mc Kenna, L.G.
    Forensic Science Ireland, DNA department, Dublin, Ireland.
    Drotz, W.
    Swedish National Forensic Centre, DNA department, Linköping, Sweden.
    Ansell, Ricky
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Swedish National Forensic Centre, DNA department, Linköping, Sweden.
    van Oorschot, R.A.
    Office of the Chief Forensic Scientist, Victoria Police Forensic Services Department, Macleod- Victoria, Australia.
    Kloosterman, A.D.
    Netherlands Forensic Institute, Biological Traces and DNA, The Hague, Netherlands.
    DNActivity: International cooperation in activity level interpretation of forensic DNA evidence.2015In: Abstract book, 7th European Academy of Forensic Science, EAFS, Prag, Tjeckien, 2015., 2015, p. 555-Conference paper (Other academic)
    Abstract [en]

    Questions posed to expert witnesses by the legal community and the courts are expanding to include not just those relating to source level (i.e. ‘who is the donor of the trace?’) but also those relating to activitity level (i.e. ‘how did the DNA get there?’). The answers to these questions are usually formulated as the probability of the evidence under alternative scenarios. As activity level questions are part of investigative and legal considerations it is of paramount importance that expert witnesses are provided with knowledge and tools to address these questions.

    To answer such questions within a probabilistic framework, empirical data is needed to estimate probabilities of transfer, persistence and recovery of DNA as well as background levels of DNA on everyday objects. There is a paucity of empirical data on these topics, but the number of studies is increasing both through in-house experiments and experimental data published in international scientific journals.

    Laboratories that conduct such studies all use different experimental setups, trace recovery strategies and techniques and DNA analysis systems and equipment. It is essential for the forensic genetics community in general to establish whether the data generated by different labs are in concordance, and can therefore be readily used by the forensic community.

    Moreover, if existing data and data generated from future experiments are made available to the (forensic) community, knowledge is needed on the key factors that underlie potential interlaboratory variation.

    The aims and objectives of this ENFSI Monopoly 2013 project are to conduct a study of methodologies and data from different laboratories and to assess the comparability of the scientific data on transfer, persistence and recovery of DNA. This comparison will allow us to identify key factors that underlie potential variation. This information will be used to setup guidelines to enable sharing and database-storage of relevant scientific

    data. This will improve the ability of forensic scientists and other professionals of the Criminal Justice System to give evidence-based answers to questions that relate to the activity level of the crime under investigation.

  • 5.
    Abadias, Gregory
    et al.
    Univ Poitiers, France.
    Sarakinos, Kostas
    Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering.
    Patsalas, Panos
    Aristotle Univ Thessaloniki, Greece.
    Preface2020In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 404, article id 126450Article in journal (Other academic)
    Abstract [en]

    n/a

  • 6.
    Abadpour, Shadab
    et al.
    Oslo Univ Hosp, Norway; Univ Oslo, Norway.
    Tyrberg, Bjorn
    AstraZeneca, Sweden.
    Schive, Simen W.
    Oslo Univ Hosp, Norway.
    Wennberg Huldt, Charlotte
    AstraZeneca, Sweden.
    Gennemark, Peter
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering. AstraZeneca, Sweden.
    Ryberg, Erik
    AstraZeneca, Sweden.
    Ryden-Bergsten, Tina
    AstraZeneca, Sweden.
    Smith, David M.
    AstraZeneca, Sweden; AstraZeneca, England.
    Korsgren, Olle
    Uppsala Univ, Sweden.
    Skrtic, Stanko
    AstraZeneca, Sweden; Univ Gothenburg, Sweden.
    Scholz, Hanne
    Oslo Univ Hosp, Norway; Univ Oslo, Norway.
    Winzell, Maria Sorhede
    AstraZeneca, Sweden.
    Inhibition of the prostaglandin D-2-GPR44/DP2 axis improves human islet survival and function2020In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 63, no 7, p. 1355-1367Article in journal (Refereed)
    Abstract [en]

    Aims/hypothesis Inflammatory signals and increased prostaglandin synthesis play a role during the development of diabetes. The prostaglandin D-2 (PGD(2)) receptor, GPR44/DP2, is highly expressed in human islets and activation of the pathway results in impaired insulin secretion. The role of GPR44 activation on islet function and survival rate during chronic hyperglycaemic conditions is not known. In this study, we investigate GPR44 inhibition by using a selective GPR44 antagonist (AZ8154) in human islets both in vitro and in vivo in diabetic mice transplanted with human islets. Methods Human islets were exposed to PGD(2) or proinflammatory cytokines in vitro to investigate the effect of GPR44 inhibition on islet survival rate. In addition, the molecular mechanisms of GPR44 inhibition were investigated in human islets exposed to high concentrations of glucose (HG) and to IL-1 beta. For the in vivo part of the study, human islets were transplanted under the kidney capsule of immunodeficient diabetic mice and treated with 6, 60 or 100 mg/kg per day of a GPR44 antagonist starting from the transplantation day until day 4 (short-term study) or day 17 (long-term study) post transplantation. IVGTT was performed on mice at day 10 and day 15 post transplantation. After termination of the study, metabolic variables, circulating human proinflammatory cytokines, and hepatocyte growth factor (HGF) were analysed in the grafted human islets. Results PGD(2) or proinflammatory cytokines induced apoptosis in human islets whereas GPR44 inhibition reversed this effect. GPR44 inhibition antagonised the reduction in glucose-stimulated insulin secretion induced by HG and IL-1 beta in human islets. This was accompanied by activation of the Akt-glycogen synthase kinase 3 beta signalling pathway together with phosphorylation and inactivation of forkhead box O-1and upregulation of pancreatic and duodenal homeobox-1 and HGF. Administration of the GPR44 antagonist for up to 17 days to diabetic mice transplanted with a marginal number of human islets resulted in reduced fasting blood glucose and lower glucose excursions during IVGTT. Improved glucose regulation was supported by increased human C-peptide levels compared with the vehicle group at day 4 and throughout the treatment period. GPR44 inhibition reduced plasma levels of TNF-alpha and growth-regulated oncogene-alpha/chemokine (C-X-C motif) ligand 1 and increased the levels of HGF in human islets. Conclusions/interpretation Inhibition of GPR44 in human islets has the potential to improve islet function and survival rate under inflammatory and hyperglycaemic stress. This may have implications for better survival rate of islets following transplantation.

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  • 7.
    Abafogi, Abdurhaman Teyib
    et al.
    Sungkyunkwan Univ, South Korea.
    Kim, Jaewon
    Sungkyunkwan Univ, South Korea.
    Lee, Jinyeop
    Sungkyunkwan Univ, South Korea.
    Mohammed, Merem Omer
    Sungkyunkwan Univ, South Korea.
    van Noort, Danny
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering. Univ Ljubljana, Slovenia; Univ Ingn and Tecnol UTEC, Peru.
    Park, Sungsu
    Sungkyunkwan Univ, South Korea; Sungkyunkwan Univ, South Korea; Sungkyunkwan Univ, South Korea.
    3D-Printed Modular Microfluidic Device Enabling Preconcentrating Bacteria and Purifying Bacterial DNA in Blood for Improving the Sensitivity of Molecular Diagnostics2020In: Sensors, E-ISSN 1424-8220, SENSORS, Vol. 20, no 4, article id 1202Article in journal (Refereed)
    Abstract [en]

    Molecular diagnostics for sepsis is still a challenge due to the presence of compounds that interfere with gene amplification and bacteria at concentrations lower than the limit of detection (LOD). Here, we report on the development of a 3D printed modular microfluidic device (3Dpm mu FD) that preconcentrates bacteria of interest in whole blood and purifies their genomic DNA (gDNA). It is composed of a W-shaped microchannel and a conical microchamber. Bacteria of interest are magnetically captured from blood in the device with antibody conjugated magnetic nanoparticles (Ab-MNPs) at 5 mL/min in the W-shaped microchannel, while purified gDNA of the preconcentrated bacteria is obtained with magnetic silica beads (MSBs) at 2 mL/min in the conical microchamber. The conical microchamber was designed to be connected to the microchannel after the capturing process using a 3D-printed rotary valve to minimize the exposure of the MSBs to interfering compounds in blood. The pretreatment process of spiked blood (2.5 mL) can be effectively completed within about 50 min. With the 3Dpm mu FD, the LOD for the target microorganism Escherichia coli O157:H7 measured by both polymerase chain reaction (PCR) with electrophoresis and quantitative PCR was 10 colony forming unit (CFU) per mL of whole blood. The results suggest that our method lowers the LOD of molecular diagnostics for pathogens in blood by providing bacterial gDNA at high purity and concentration.

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  • 8.
    Abara, Precious Ugo
    et al.
    Univ Padua, Italy; Tech Univ Munich, Germany.
    Ticozzi, Francesco
    Univ Padua, Italy; Dartmouth Coll, NH 03755 USA.
    Altafini, Claudio
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Spectral Conditions for Stability and Stabilization of Positive Equilibria for a Class of Nonlinear Cooperative Systems2018In: IEEE Transactions on Automatic Control, ISSN 0018-9286, E-ISSN 1558-2523, Vol. 63, no 2, p. 402-417Article in journal (Refereed)
    Abstract [en]

    Nonlinear cooperative systems associated to vector fields that are concave or subhomogeneous describe well interconnected dynamics that are of key interest for communication, biological, economical, and neural network applications. For this class of positive systems, we provide conditions that guarantee existence, uniqueness and stability of strictly positive equilibria. These conditions can be formulated directly in terms of the spectral radius of the Jacobian of the system. If control inputs are available, then it is shown how to use state feedback to stabilize an equilibrium point in the interior of the positive orthant.

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  • 9.
    Abarghouyi, Hadis
    et al.
    IUST, Iran; MTNi Co, Iran.
    Razavizadeh, S. Mohammad
    IUST, Iran.
    Björnson, Emil
    Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, Faculty of Science & Engineering.
    QoE-Aware Beamforming Design for Massive MIMO Heterogeneous Networks2018In: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 67, no 9, p. 8315-8323Article in journal (Refereed)
    Abstract [en]

    One of the main goals of the future wireless networks is improving the users quality of experience (QoE). In this paper, we consider the problem of the QoE-based resource allocation in the downlink of a massive multiple-input multiple-output heterogeneous network. The network consists of a macrocell with a number of small cells embedded in it. The small cells base stations (BSs) are equipped with a few antennas, while the macro BS is equipped with a massive number of antennas. We consider the two services Video and Web Browsing and design the beamforming vectors at the BSs. The objective is to maximize the aggregated mean opinion score (MOS) of the users under constraints on the BSs powers and the required quality of service of the users. We also consider extra constraints on the QoE of users to more strongly enforce the QoE in the beamforming design. To reduce the complexity of the optimization problem, we suggest suboptimal and computationally efficient solutions. Our results illustrate that increasing the number of antennas at the BSs and also increasing the number of small cells antennas in the network leads to a higher user satisfaction.

  • 10.
    Abarkan, Myriam
    et al.
    Univ Bordeaux, France.
    Pirog, Antoine
    Univ Bordeaux, France.
    Mafilaza, Donnie
    Univ Bordeaux, France.
    Pathak, Gaurav
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering. MOC, France.
    NKaoua, Gilles
    Univ Bordeaux, France.
    Puginier, Emilie
    Univ Bordeaux, France.
    OConnor, Rodney
    MOC, France.
    Raoux, Matthieu
    Univ Bordeaux, France.
    Donahue, Mary
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering. MOC, France.
    Renaud, Sylvie
    Univ Bordeaux, France.
    Lang, Jochen
    Univ Bordeaux, France.
    Vertical Organic Electrochemical Transistors and Electronics for Low Amplitude Micro-Organ Signals2022In: Advanced Science, E-ISSN 2198-3844, Vol. 9, no 8, article id 2105211Article in journal (Refereed)
    Abstract [en]

    Electrical signals are fundamental to key biological events such as brain activity, heartbeat, or vital hormone secretion. Their capture and analysis provide insight into cell or organ physiology and a number of bioelectronic medical devices aim to improve signal acquisition. Organic electrochemical transistors (OECT) have proven their capacity to capture neuronal and cardiac signals with high fidelity and amplification. Vertical PEDOT:PSS-based OECTs (vOECTs) further enhance signal amplification and device density but have not been characterized in biological applications. An electronic board with individually tuneable transistor biases overcomes fabrication induced heterogeneity in device metrics and allows quantitative biological experiments. Careful exploration of vOECT electric parameters defines voltage biases compatible with reliable transistor function in biological experiments and provides useful maximal transconductance values without influencing cellular signal generation or propagation. This permits successful application in monitoring micro-organs of prime importance in diabetes, the endocrine pancreatic islets, which are known for their far smaller signal amplitudes as compared to neurons or heart cells. Moreover, vOECTs capture their single-cell action potentials and multicellular slow potentials reflecting micro-organ organizations as well as their modulation by the physiological stimulator glucose. This opens the possibility to use OECTs in new biomedical fields well beyond their classical applications.

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  • 11.
    Abbas, Malik Waseem
    et al.
    Natl Inst Biotechnol and Genet Engn, Pakistan.
    Soomro, Razium Ali
    Natl Inst Biotechnol and Genet Engn, Pakistan; Univ Sindh, Pakistan; Univ Bristol, England.
    Kalwar, Nazar Hussain
    Shah Abdul Latif Univ, Pakistan.
    Zahoor, Mehvish
    Natl Inst Biotechnol and Genet Engn, Pakistan.
    Avci, Ahmet
    Selcuk Univ, Turkey.
    Pehlivan, Erol
    Selcuk Univ, Turkey.
    Hallam, Keith Richard
    Univ Bristol, England.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Carbon quantum dot coated Fe3O4 hybrid composites for sensitive electrochemical detection of uric acid2019In: Microchemical journal (Print), ISSN 0026-265X, E-ISSN 1095-9149, Vol. 146, p. 517-524Article in journal (Refereed)
    Abstract [en]

    The study explores carbon quantum dots (C-dots) as potential candidates for enhancing the signal sensitivity of an electrochemical sensor devised for biologically important molecule, such as uric acid (UA). The C-dots were evaluated for their electrochemical characteristics in combination with Fe3O4 nanoparticles (Fe3O4 NPs), which were applied as the primary electro-catalytic promoter. The hybrid nanocomposite (C-dots/Fe3O4 HCs) formation was achieved by facilitating the adsorption of C-dots over Fe3O4 NPs using amine-carbonyl interactions. Unlike, one pot method, the proposed strategy enables aggregation-free coverage of Fe3O4 NPs with highly conductive layer of C-dots that can act as conduction centres to support ultra-fast electron transfer kinetics to satisfy the need of high signal sensitivity. The hybrid composite demonstrated remarkable signal improvement when tested against the electrochemical oxidation of UA. The heighten current response and lower over-potential values enabled development of a DC-amperometric (DC-AMP) sensor for UA with a linear working range of 0.01 to 0.145 mu M and signal sensitivity measurable up to 6.0 x 10(-9) M. The said improvement was manifested as a synergetic outcome of active redox couple (Fe (III/II)), larger surface area of Fe3O4 NPs engulfed with a layer of highly conductive C-dots acting as efficient charge sensitisers.

  • 12.
    Abbas, Zaheer
    et al.
    Beijing Univ Chem Technol, Peoples R China.
    Soomro, Razium Ali
    Beijing Univ Chem Technol, Peoples R China; Beijing Univ Chem Technol, Peoples R China.
    Kalwar, Nazar Hussain
    Shah Abdul Latif Univ Khairpur, Pakistan.
    Tunesi, Mawada
    Beijing Univ Chem Technol, Peoples R China.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Karakus, Selcan
    Istanbul Univ Cerrahpa Avcilar, Turkey.
    Kilislioglu, Ayben
    Istanbul Univ Cerrahpa Avcilar, Turkey.
    In Situ Growth of CuWO4 Nanospheres over Graphene Oxide for Photoelectrochemical (PEC) Immunosensing of Clinical Biomarker2020In: Sensors, E-ISSN 1424-8220, SENSORS, Vol. 20, no 1, article id 148Article in journal (Refereed)
    Abstract [en]

    Procalcitonin (PCT) protein has recently been identified as a clinical marker for bacterial infections based on its better sepsis sensitivity. Thus, an increased level of PCT could be linked with disease diagnosis and therapeutics. In this study, we describe the construction of the photoelectrochemical (PEC) PCT immunosensing platform based on it situ grown photo-active CuWO4 nanospheres over reduced graphene oxide layers (CuWO4@rGO). The in situ growth strategy enabled the formation of small nanospheres (diameter of 200 nm), primarily composed of tiny self-assembled CuWO4 nanoparticles (2-5 nm). The synergic coupling of CuWO4 with rGO layers constructed an excellent photo-active heterojunction for photoelectrochemical (PEC) sensing. The platform was then considered for electrocatalytic (EC) mechanism-based detection of PCT, where inhibition of the photocatalytic oxidation signal of ascorbic acid (AA), subsequent to the antibody-antigen interaction, was recorded as the primary signal response. This inhibition detection approach enabled sensitive detection of PCT in a concentration range of 10 pgmL(-1) to 50 ng.mL(-1) with signal sensitivity achievable up to 0.15 pgmL(-1). The proposed PEC hybrid (CuWO4@rGO) could further be engineered to detect other clinically important species.

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  • 13.
    Abbasy, Leila
    et al.
    Tabriz University of Medical Sciences, Iran.
    Mohammadzadeh, Arezoo
    Tabriz University of Medical Sciences, Iran.
    Hasanzadeh, Mohammad
    Tabriz University of Medical Sciences, Iran.
    Razmi, Nasrin
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Development of a reliable bioanalytical method based on prostate specific antigen trapping on the cavity of molecular imprinted polymer towards sensing of PSA using binding affinity of PSA-MIP receptor: A novel biosensor2020In: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 188, article id 113447Article in journal (Refereed)
    Abstract [en]

    In this study, electrically-conducting poly [Toluidine Blue (PTB)] was applied as artificial receptor. It was organized by molecular imprinting approaches and via electrochemical technique for the sensitive monitoring of prostate-specific antigen (PSA). The protein-imprinted PTB was electropolymerized in a pre-formed glutaraldehyde-cysteamine (GA-Cys A) matrix on the surface of gold electrode, which significantly boosted the stability against degradation of the Molecular Imprinted Polymer (MIP) on the surface of pre-modified gold electrode. Moreover, the MIP bio-receptor ability towards protein recognition was explored by some electrochemical techniques. The binding affinity of MIP system was considerably upper than that of non-imprinted polymer (NIP) system, indicating the success of the method in generating imprinted materials that was specifically use to PSA protein. The incubation of the MIP modified electrode in various concentration of PSA (from 1-60 μg/L) resulted in the increase of the Fe (CN)63-/4- redox peak current. The bio-device also showed linear response from 1-60 μg/L and LLOQ of 1 μg/L by using DPV technique, leading to PSA monitoring in clinical samples. The proposed MIP-based biosensor was satisfactorily applied to the determination of PSA in human plasma samples. Therefore, the developed bio-device provides a new approach for sensitive, simple, rapid, and cost-effective monitoring of 1 μg/L of PSA. Notably, this approach could appear as an appropriate candidate for point-of-care (POC) use in clinical and biomedical analyses.

  • 14.
    Abbey-Lee, Robin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Max Planck Inst Ornithol, Germany.
    Araya-Ajoy, Yimen G.
    Norwegian Univ Sci and Technol, Norway.
    Mouchet, Alexia
    Max Planck Inst Ornithol, Germany.
    Moiron, Maria
    Max Planck Inst Ornithol, Germany.
    Stuber, Erica F.
    Univ Nebraska Lincoln, NE USA.
    Kempenaers, Bart
    Max Planck Inst Ornithol, Germany.
    Dingemanse, Niels J.
    Max Planck Inst Ornithol, Germany; Ludwig Maximilians Univ Munchen, Germany.
    Does perceived predation risk affect patterns of extra-pair paternity? A field experiment in a passerine bird2018In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 32, no 4, p. 1001-1010Article in journal (Refereed)
    Abstract [en]

    Non-consumptive predator effects have been shown to influence a wide range of behavioural, life history and morphological traits. Extra-pair reproduction is widespread among socially monogamous birds and may incur predation costs. Consequently, altered rates of extra-pair reproduction are expected in circumstances characterized by increased adult perceived predation risk. In addition, extra-pair reproduction is expected to be most affected for birds with phenotypes that generally increase predation risk (such as more active individuals). In two consecutive years, perceived predation risk was manipulated for great tits Parus major breeding in 12 nest-box plots by broadcasting sounds of their main predator (European sparrowhawk Accipiter nisus; six plots). As a control treatment, sounds of a sympatric, avian non-predator species were broadcast (Eurasian blackbird Turdus merula; six plots). Levels of extra-pair paternity did not differ between plots with different predation risk treatments. Males that moved more in a novel environment (more active or faster exploring) tended to have offspring with fewer partners, but this effect did not vary with predation risk treatment. From an adaptive viewpoint, predation costs associated with extra-pair reproduction may be small and may not outweigh the benefits of extra-pair behaviour. Research on a broader range of taxa with different mating strategies is now needed to confirm the generality of our findings.

  • 15.
    Abbey-Lee, Robin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Max Planck Inst Ornithol, Germany.
    Dingemanse, Niels J.
    Ludwig Maximilians Univ Munchen, Germany.
    Adaptive individual variation in phenological responses to perceived predation levels2019In: Nature Communications, E-ISSN 2041-1723, Vol. 10, article id 1601Article in journal (Refereed)
    Abstract [en]

    The adaptive evolution of timing of breeding (a component of phenology) in response to environmental change requires individual variation in phenotypic plasticity for selection to act upon. A major question is what processes generate this variation. Here we apply multi-year manipulations of perceived predation levels (PPL) in an avian predator-prey system, identifying phenotypic plasticity in phenology as a key component of alternative behavioral strategies with equal fitness payoffs. We show that under low-PPL, faster (versus slower) exploring birds breed late (versus early); the pattern is reversed under high-PPL, with breeding synchrony decreasing in conjunction. Timing of breeding affects reproductive success, yet behavioral types have equal fitness. The existence of alternative behavioral strategies thus explains variation in phenology and plasticity in reproductive behavior, which has implications for evolution in response to anthropogenic change.

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  • 16.
    Abbey-Lee, Robin N.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Kreshchenko, Anastasia
    Mechanical and Aeronautical Engineering Division L5, Department of Mechanical, Aerospace & Civil Engineering, Dalton Nuclear Institute, FSE Research Institutes,The University of Manchester, UK.
    Fernandez Sala, Xavier
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Petkova, Irina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. School of Biological Sciences, Centre for Ecology,Evolution and Behaviour, Royal Holloway University of London, Egham UK.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Effects of monoamine manipulations on the personality and gene expression of three-spined sticklebacks2019In: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 222, no 20, article id jeb211888Article in journal (Refereed)
    Abstract [en]

    Among-individual behavioral differences (i.e. animal personality) are commonly observed across taxa, although the underlying, causal mechanisms of such differences are poorly understood. Animal personality has been correlated with physiological functions as well as fitness-related traits. Variation in many aspects of monoamine systems, such as metabolite levels and gene polymorphisms, has been linked to behavioral variation. Therefore, here we experimentally investigated the potential role of monoamines in explaining individual variation in personality, using two common pharmaceuticals that respectively alter the levels of serotonin and dopamine in the brain: fluoxetine and ropinirole. We exposed three-spined sticklebacks, a species that shows animal personality, to either chemical alone or to a combination of the two chemicals, for 18 days. During the experiment, fish were assayed at four time points for the following personality traits: exploration, boldness, aggression and sociability. To quantify brain gene expression on short- and longer-term scales, fish were sampled at two time points. Our results show that monoamine manipulations influence fish behavior. Specifically, fish exposed to either fluoxetine or ropinirole were significantly bolder, and fish exposed to the two chemicals together tended to be bolder than control fish. Our monoamine manipulations did not alter the gene expression of monoamine or stress-associated neurotransmitter genes, but control, untreated fish showed covariation between gene expression and behavior. Specifically, exploration and boldness were predicted by genes in the dopaminergic, serotonergic and stress pathways, and sociability was predicted by genes in the dopaminergic and stress pathways. These results add further support to the links between monoaminergic systems and personality, and show that exposure to monoamines can causally alter animal personality.

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  • 17.
    Abbey-Lee, Robin N.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Kreshchenko, Anastasia
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Fernandez Sala, Xavier
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Petkova, Irina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Effects of monoamine manipulations on the personality and gene expression of three-spined sticklebacks2019Data set
    Abstract [en]

    Among-individual behavioral differences (i.e. animal personality) are commonly observed across taxa, although the underlying, causal mechanisms of such differences are poorly understood. Animal personality has been implicated in correlations with physiological functions as well as affecting fitness-related traits. Variation in many aspects of monoamine systems, such as metabolite levels and gene polymorphisms, has been linked to behavioral variation. Therefore, here we investigated the potential role of monoamines in explaining individual variation in personality, using two common pharmaceuticals that respectively alter the levels of serotonin and dopamine in the brain: fluoxetine and ropinirole. We exposed three- spined sticklebacks, a species that shows animal personality, to either chemical alone or to a combination of the two chemicals, for 18 days. During the experiment, fish were assayed at four time points for the following personality traits: exploration, boldness, aggression and sociability. To quantify brain gene expression on short- and longer-term scales, fish were sampled at two time points. Our results show that monoamine manipulations influence fish behavior. Specifically, fish exposed to either fluoxetine or ropinirole were significantly bolder, and fish exposed to the two chemicals together tended to be bolder than control fish. Our monoamine manipulations did not alter the gene expression of monoamine or stress-associated neurotransmitter genes, but control, untreated fish showed covariation between gene expression and behavior. Specifically, exploration and boldness were predicted by genes in the dopaminergic, serotonergic and stress pathways, and sociability was predicted by genes in the dopaminergic and stress pathways. These results add further support to the links between monoaminergic systems and personality, and show that exposure to monoamines can causally alter animal personality.

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    Raw Data
  • 18.
    Abbey-Lee, Robin N.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Uhrig, Emily J.
    Department of Zoology, Stockholm University, 10691 Stockholm, Sweden.
    Zidar, Josefina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Favati, Anna
    Department of Zoology, Stockholm University, 10691 Stockholm, Sweden.
    Almberg, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Dahlblom, Josefin
    Department of Neuroscience, Uppsala Biomedical Centre BMC, Uppsala University, Uppsala, Sweden.
    Winberg, Svante
    Department of Neuroscience, Uppsala Biomedical Centre BMC, Uppsala University, Uppsala, Sweden.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    The influence of rearing on behavior, brain monoamines and gene expression in three-spined sticklebacks2018Data set
    Abstract [en]
    1. The causes of individual variation in behavior are often not well understood, and potential underlying mechanisms include both intrinsic and extrinsic factors, such as early environmental, physiological, and genetic differences.
    2. In an exploratory laboratory study, we raised three-spined sticklebacks (Gasterosteus aculeatus) under 4 different environmental conditions (simulated predator environment, complex environment, variable social environment, and control). We investigated how these manipulations related to behavior, brain physiology and gene expression later in life, with focus on brain dopamine and serotonin levels, turnover rates, and gene expression.
    3. The different rearing environments influenced behavior and gene expression, but did not alter monoamine levels or metabolites. Specifically, compared to control fish, fish exposed to a simulated predator environment tended to be less aggressive, more exploratory, and more neophobic; and fish raised in both complex and variable social environments tended to be less neophobic. Exposure to a simulated predator environment tended to lower expression of dopamine receptor DRD4A, a complex environment increased expression of dopamine receptor DRD1B, while a variable social environment tended to increase serotonin receptor 5-HTR2B and increased serotonin transporter SLC6A4A expression. Despite both behavior and gene expression varying with early environment, there was no evidence that gene expression mediated the relationship between early environment and behavior.
    4. Our results confirm that environmental conditions early in life can affect phenotypic variation. However, the mechanistic pathway of the monoaminergic systems translating early environmental variation into observed behavioral responses was not detected.
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    dataset
  • 19.
    Abbey-Lee, Robin N.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Uhrig, Emily
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Zidar, Josefina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Favati, A.
    Department of Zoology, Stockholm University, Stockholm, Sweden.
    Almberg, J.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Dahlbom, J.
    Department of Neuroscience, Uppsala Biomedical Centre BMC, Uppsala University, Uppsala, Sweden.
    Winberg, S.
    Department of Neuroscience, Uppsala Biomedical Centre BMC, Uppsala University, Uppsala, Sweden.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    The Influence of Rearing on Behavior, Brain Monoamines, and Gene Expression in Three-Spined Sticklebacks2018In: Brain, behavior, and evolution, ISSN 0006-8977, E-ISSN 1421-9743, Vol. 91, no 4, p. 201-213Article in journal (Refereed)
    Abstract [en]

    The causes of individual variation in behavior are often not well understood, and potential underlying mechanisms include both intrinsic and extrinsic factors, such as early environmental, physiological, and genetic differences. In an exploratory laboratory study, we raised three-spined sticklebacks <i>(Gasterosteus aculeatus)</i> under 4 different environmental conditions (simulated predator environment, complex environment, variable social environment, and control). We investigated how these manipulations related to behavior, brain physiology, and gene expression later in life, with focus on brain dopamine and serotonin levels, turnover rates, and gene expression. The different rearing environments influenced behavior and gene expression, but did not alter monoamine levels or metabolites. Specifically, compared to control fish, fish exposed to a simulated predator environment tended to be less aggressive, more exploratory, and more neophobic; and fish raised in both complex and variable social environments tended to be less neophobic. Exposure to a simulated predator environment tended to lower expression of dopamine receptor DRD4A, a complex environment increased expression of dopamine receptor DRD1B, while a variable social environment tended to increase serotonin receptor 5-HTR2B and serotonin transporter SLC6A4A expression. Despite both behavior and gene expression varying with early environment, there was no evidence that gene expression mediated the relationship between early environment and behavior. Our results confirm that environmental conditions early in life can affect phenotypic variation. However, the mechanistic pathway of the monoaminergic systems translating early environmental variation into observed behavioral responses was not detected.

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  • 20.
    Abbey-Lee, Robin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Uhrig, Emily
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Southern Oregon Univ, OR 97520 USA.
    Garnham, Laura
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Lundgren, Kristoffer
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Child, Sarah
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Univ Manchester, England.
    Lovlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Experimental manipulation of monoamine levels alters personality in crickets2018In: Scientific Reports, E-ISSN 2045-2322, Vol. 8, article id 16211Article in journal (Refereed)
    Abstract [en]

    Animal personality has been described in a range of species with ecological and evolutionary consequences. Factors shaping and maintaining variation in personality are not fully understood, but monoaminergic systems are consistently linked to personality variation. We experimentally explored how personality was influenced by alterations in two key monoamine systems: dopamine and serotonin. This was done using ropinirole and fluoxetine, two common human pharmaceuticals. Using the Mediterranean field cricket (Gryllus bimaculatus), we focused on the personality traits activity, exploration, and aggression, with confirmed repeatability in our study. Dopamine manipulations explained little variation in the personality traits investigated, while serotonin manipulation reduced both activity and aggression. Due to limited previous research, we created a dose-response curve for ropinirole, ranging from concentrations measured in surface waters to human therapeutic doses. No ropinirole dose level strongly influenced cricket personality, suggesting our results did not come from a dose mismatch. Our results indicate that the serotonergic system explains more variation in personality than manipulations of the dopaminergic system. Additionally, they suggest that monoamine systems differ across taxa, and confirm the importance of the mode of action of pharmaceuticals in determining their effects on behaviour.

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  • 21.
    Abbott, Rebecca
    et al.
    Northwestern Univ, IL 60611 USA.
    Peolsson, Anneli
    Linköping University, Department of Medical and Health Sciences, Division of Physiotherapy. Linköping University, Faculty of Medicine and Health Sciences.
    West, Janne
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Medicine and Health Sciences.
    Elliott, James M.
    Northwestern Univ, IL 60611 USA; Univ Queensland, Australia; Zurich Univ Appl Sci, Switzerland.
    Åslund, Ulrika
    Linköping University, Department of Medical and Health Sciences, Division of Physiotherapy. Linköping University, Faculty of Medicine and Health Sciences.
    Karlsson, Anette
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Dahlqvist Leinhard, Olof
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    The qualitative grading of muscle fat infiltration in whiplash using fat and water magnetic resonance imaging2018In: The spine journal, ISSN 1529-9430, E-ISSN 1878-1632, Vol. 18, no 5, p. 717-725Article in journal (Refereed)
    Abstract [en]

    BACKGROUND CONTEXT: The development of muscle fat infiltration (MFI) in the neck muscles is associated with poor functional recovery following whiplash injury. Custom software and time-consuming manual segmentation of magnetic resonance imaging (MRI) is required for quantitative analysis and presents as a barrier for clinical translation. PURPOSE: The purpose of this work was to establish a qualitative MRI measure for MFI and evaluate its ability to differentiate between individuals with severe whiplash-associated disorder (WAD), mild or moderate WAD, and healthy controls. STUDY DESIGN/SETTING: This is a cross-sectional study. PATIENT SAMPLE: Thirty-one subjects with WAD and 31 age-and sex-matched controls were recruited from an ongoing randomized controlled trial. OUTCOME MEASURES: The cervical multifidus was visually identified and segmented into eighths in the axial fat/water images (C4-C7). Muscle fat infiltration was assessed on a visual scale: 0 for no or marginal MFI, 1 for light MFI, and 2 for distinct MFI. The participants with WAD were divided in two groups: mild or moderate and severe based on Neck Disability Index % scores. METHODS: The mean regional MFI was compared between the healthy controls and each of the WAD groups using the Mann-Whitney U test. Receiver operator characteristic (ROC) analyses were carried out to evaluate the validity of the qualitative method. RESULTS: Twenty (65%) patients had mild or moderate disability and 11 (35%) were considered severe. Inter- and intra-rater reliability was excellent when grading was averaged by level or when frequency of grade II was considered. Statistically significant differences (pamp;lt;.05) in regional MFI were particularly notable between the severe WAD group and healthy controls. The ROC curve, based on detection of distinct MFI, showed an area-under-the curve of 0.768 (95% confidence interval 0.59-0.94) for discrimination of WAD participants. CONCLUSIONS: These preliminary results suggest a qualitative MRI measure for MFI is reliable and valid, and may prove useful toward the classification of WAD in radiology practice. (C) 2017 Elsevier Inc. All rights reserved.

  • 22.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Algergawy, Alsayed
    Friedrich Schiller University Jena, Germany.
    Amardeilh, Florence
    Elzeard.co, Paris, France.
    Amini, Reihaneh
    Data Semantics (DaSe) Laboratory, Kansas State University, USA.
    Fallatah, Omaima
    Information School, The University of Sheffield, Sheffield, UK.
    Faria, Daniel
    LASIGE, Faculdade de Ciencias, Universidade de Lisboa, Portugal .
    Fundulaki, Irini
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Harrow, Ian
    Pistoia Alliance Inc., USA.
    Hertling, Sven
    University of Mannheim, Germany.
    Hitzler, Pascal
    Data Semantics (DaSe) Laboratory, Kansas State University, USA.
    Huschka, Martin
    Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI, Germany.
    Ibanescu, Liliana
    AgroParisTech, UMR MIA-Paris/INRAE, France.
    Jimenez-Ruiz, Ernesto
    City, University of London, UK and Department of Informatics, University of Oslo, Norway.
    Karam, Naouel
    Fraunhofer FOKUS, Berlin, Germany and Institute for Applied Informatics (InfAI), University of Leipzig, Germany.
    Laadhar, Amir
    Department of Computer Science, Aalborg University, Denmark.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology. University of Gävle, Sweden.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Ying
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Michel, Franck
    University Cote d’Azur, CNRS, Inria, France.
    Nasr, Engy
    Freiburg Galaxy Team, University of Freiburg, Germany.
    Paulheim, Heiko
    University of Mannheim, Germany.
    Pesquita, Catia
    LASIGE, Faculdade de Ciencias, Universidade de Lisboa, Portugal .
    Portisch, Jan
    University of Mannheim, Germany.
    Roussey, Catherine
    INRAE Centre Clermont-ARA, laboratoire TSCF, France.
    Saveta, Tzanina
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Shvaiko, Pavel
    Trentino Digitale SpA, Trento, Italy.
    Splendiani, Andrea
    Pistoia Alliance Inc., USA.
    Trojahn, Cassia
    IRIT & Universite Toulouse II, Toulouse, France .
    Vatascinova, Jana
    Prague University of Economics and Business, Czech Republic.
    Yaman, Beyza
    ADAPT Centre, Dublin City University, Ireland.
    Zamazal, Ondrej
    Prague University of Economics and Business, Czech Republic.
    Zhou, Lu
    Data Semantics (DaSe) Laboratory, Kansas State University, USA.
    Results of theOntology Alignment Evaluation Initiative 20212021In: Proceedings of the 16th International Workshop on Ontology Matching: co-located with the 20th International Semantic Web Conference (ISWC 2021) / [ed] Pavel Shvaiko, Jérôme Euzenat, Ernesto Jiménez-Ruiz, Oktie Hassanzadeh, Cássia Trojahn, CEUR Workshop proceedings , 2021, p. 62-108Conference paper (Refereed)
    Abstract [en]

    The Ontology Alignment Evaluation Initiative (OAEI) aims at comparing ontology matching systems on precisely defined test cases. These test cases can be based on ontologies of different levels of complexity and use different evaluation modalities (e.g., blind evaluation, open evaluation, or consensus). The OAEI 2021 campaign offered 13 tracks and was attended by 21 participants.This paper is an overall presentation of that campaign.

  • 23.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Algergawy, Alsayed
    Friedrich Schiller University Jena, Germany.
    Amini, Reihaneh
    Kansas State University, USA.
    Faria, Daniel
    BioData.pt, INESC-ID, Lisbon, Portugal.
    Fundulaki, Irini
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Harrow, Ian
    Pistoia Alliance Inc., USA.
    Hertling, Sven
    University of Mannheim, Germany.
    Jimenez-Ruiz, Ernesto
    City, University of London, UK, and , University of Oslo, Norway.
    Jonquet, Clement
    LIRMM, University of Montpellier & CNRS, France.
    Karam, Naouel
    Fraunhofer FOKUS, Berlin, Germany.
    Khiat, Abderrahmane
    Fraunhofer IAIS, Sankt Augustin, Germany.
    Laadhar, Amir
    LIRMM, University of Montpellier & CNRS, France.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Ying
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Hitzler, Pascal
    Kansas State University, USA.
    Paulheim, Heiko
    University of Mannheim, Germany.
    Pesquita, Catia
    Universidade de Lisboa, Portugal.
    Saveta, Tzanina
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Shvaiko, Pavel
    TasLab, Trentino Digitale SpA, Trento, Italy.
    Splendiani, Andrea
    Pistoia Alliance Inc., USA.
    Thieblin, Elodie
    Logilab, France.
    Trojahn, Cassia
    IRIT & Universite Toulouse II, Toulouse, France.
    Vatascinova, Jana
    University of Economics, Prague, Czech Republic.
    Yaman, Beyza
    Dublin City University, Ireland.
    Zamazal, Ondrej
    University of Economics, Prague, Czech Republic.
    Zhou, Lu
    Kansas State University, USA.
    Results of theOntology Alignment Evaluation Initiative 20202020In: Proceedings of the 15th International Workshop on Ontology Matching: co-located with the 19th International Semantic Web Conference (ISWC 2020) / [ed] Pavel Shvaiko, Jérôme Euzenat, Ernesto Jiménez-Ruiz, Oktie Hassanzadeh, Cássia Trojahn, Aachen, Germany: CEUR Workshop proceedings , 2020, p. 92-138Conference paper (Refereed)
    Abstract [en]

    The Ontology Alignment Evaluation Initiative (OAEI) aims at comparing ontology matching systems on precisely defined test cases. These test cases can be based on ontologies of different levels of complexity and use different evaluation modalities (e.g., blind evaluation, open evaluation, or consensus).The OAEI 2020 campaign offered 12 tracks with 36 test cases, and was attended by 19 participants. This paper is an overall presentation of that campaign. 

  • 24.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Algergawy, Alsayed
    Heinz Nixdorf Chair for Distributed Information Systems, Friedrich Schiller University Jena, Germany; Chair of Data and Knowledge Engineering, University of Passau, Germany.
    Buche, Patrice
    UMR IATE, INRAE, University of Montpellier, France.
    Castro, Leyla J.
    ZB MED Information Centre for Life Sciences, Germany.
    Chen, Jiaoyan
    Department of Computer Science, The University of Manchester, UK.
    Coulet, Adrien
    Inria Paris, France; Centre de Recherche des Cordeliers, Inserm, Université Paris Cité, Sorbonne Université, France.
    Cufi, Julien
    UMR IATE, INRAE, University of Montpellier, France.
    Dong, Hang
    Department of Computer Science, University of Oxford, UK.
    Fallatah, Omaima
    Department of Data Science, Umm Al-Qura University, Saudi Arabia.
    Faria, Daniel
    INESC-ID / IST, University of Lisbon, Portugal.
    Fundulaki, Irini
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Hertling, Sven
    Data and Web Science Group, University of Mannheim, Germany.
    He, Yuan
    Department of Computer Science, University of Oxford, UK.
    Horrocks, Ian
    Department of Computer Science, University of Oxford, UK.
    Huschka, Martin
    Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI, Germany.
    Ibanescu, Liliana
    Université Paris-Saclay, INRAE, AgroParisTech, UMR MIA Paris-Saclay, France.
    Jain, Sarika
    National Institute of Technology Kurukshetra, India.
    Jiménez-Ruiz, Ernesto
    City, University of London, UK; SIRIUS, University of Oslo, Norway.
    Karam, Naouel
    Institute for Applied Informatics, University of Leipzig, Germany.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Ying
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Monnin, Pierre
    University Côte d’Azur, Inria, CNRS, I3S, France.
    Nasr, Engy
    Albert Ludwig University of Freiburg, Germany.
    Paulheim, Heiko
    Data and Web Science Group, University of Mannheim, Germany.
    Pesquita, Catia
    LASIGE, Faculdade de Ciências, Universidade de Lisboa, Portugal.
    Saveta, Tzanina
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Shvaiko, Pavel
    Trentino Digitale SpA, Trento, Italy.
    Sousa, Guilherme
    Institut de Recherche en Informatique de Toulouse, France.
    Trojahn, Cássia
    Institut de Recherche en Informatique de Toulouse, France.
    Vatascinova, Jana
    Prague University of Economics and Business, Czech Republic.
    Wu, Mingfang
    Australian Research Data Commons.
    Yaman, Beyza
    ADAPT Centre, Trinity College Dublin.
    Zamazal, Ondřej
    Prague University of Economics and Business, Czech Republic.
    Zhou, Lu
    Flatfee Corp, USA.
    Results of the Ontology Alignment Evaluation Initiative 20232023In: Proceedings of the 18th International Workshop on Ontology Matching co-located with the 22nd International Semantic Web Conference (ISWC 2023), Athens, Greece, November 7, 2023. / [ed] Pavel Shvaiko, Jérôme Euzenat, Ernesto Jiménez-Ruiz, Oktie Hassanzadeh, Cássia Trojahn, CEUR Workshop Proceedings , 2023, Vol. 3591, p. 97-139Conference paper (Refereed)
  • 25.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Algergawy, Alsayed
    Heinz Nixdorf Chair for Distributed Information Systems, Friedrich Schiller University Jena, Germany.
    Buche, Patrice
    UMR IATE, INRAE, University of Montpellier, France.
    Castro, Leyla J.
    ZB MED Information Centre for Life Sciences, Germany.
    Chen, Jiaoyan
    Department of Computer Science, The University of Manchester, UK.
    Dong, Hang
    Department of Computer Science, University of Oxford, UK.
    Fallatah, Omaima
    Information School, The University of Sheffield, Sheffield, UK.
    Faria, Daniel
    University of Lisbon, Portugal.
    Fundulaki, Irini
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Hertling, Sven
    Data and Web Science Group, University of Mannheim, Germany.
    He, Yuan
    Department of Computer Science, University of Oxford, UK.
    Horrocks, Ian
    Department of Computer Science, University of Oxford, UK.
    Huschka, Martin
    Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI, Germany.
    Ibanescu, Liliana
    Universite Paris-Saclay, INRAE, AgroParisTech, UMR MIA Paris-Saclay, France.
    Jimenez-Ruiz, Ernesto
    City, University of London, UK & SIRIUS, University of Oslo, Norway.
    Karam, Naouel
    Fraunhofer FOKUS & Institute for Applied Informatics, University of Leipzig, Germany.
    Laadhar, Amir
    University of Stuttgart, Germany.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology. Högskolan i Gävle.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Ying
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Michel, Franck
    University Cote d’Azur, CNRS, Inria.
    Nasr, Engy
    Albert Ludwig University of Freiburg, Germany.
    Paulheim, Heiko
    Data and Web Science Group, University of Mannheim, Germany.
    Pesquita, Catia
    LASIGE, Faculdade de Ciencias, Universidade de Lisboa, Portugal.
    Saveta, Tzanina
    Institute of Computer Science-FORTH, Heraklion, Greece.
    Shvaiko, Pavel
    Trentino Digitale SpA, Trento, Italy.
    Trojahn, Cassia
    Institut de Recherche en Informatique de Toulouse, France.
    Verhey, Chantelle
    World Data System, International Technology Office, USA.
    Wu, Mingfang
    Australian Research Data Commons.
    Yaman, Beyza
    ADAPT Centre, Trinity College Dublin.
    Zamazal, Ondrej
    Prague University of Economics and Business, Czech Republic.
    Zhou, Lu
    TigerGraph, Inc. USA.
    Results of the Ontology Alignment EvaluationInitiative 20222022In: Proceedings of the 17th International Workshop on Ontology Matching (OM 2022): co-located with the 21th International Semantic Web Conference (ISWC 2022) / [ed] Pavel Shvaiko, Jerome Euzenat, Ernesto Jimenez-Ruiz, Oktie Hassanzadeh, Cassia Trojahn, CEUR Workshop Proceedings , 2022, p. 84-128Conference paper (Refereed)
    Abstract [en]

    The Ontology Alignment Evaluation Initiative (OAEI) aims at comparing ontology matching systems on precisely defined test cases. These test cases can be based on ontologies of different levels of complexity and use different evaluation modalities. The OAEI 2022 campaign offered 14 tracks and was attended by18 participants. This paper is an overall presentation of that campaign

  • 26.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Armiento, Rickard
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering. Högskolan i Gävle, Gävle, Sweden.
    A First Step towards a Tool for Extending Ontologies2021In: Proceedings of the Sixth International Workshop on the Visualization and Interaction for Ontologies and Linked Data: co-located with the 20th International Semantic Web Conference (ISWC 2021) / [ed] Patrick Lambrix, Catia Pesquita, Vitalis Wiens, CEUR Workshop proceedings , 2021, p. 1-12Conference paper (Refereed)
    Abstract [en]

    Ontologies have been proposed as a means towards making data FAIR (Findable, Accessible, Interoperable, Reusable). This has attracted much interest in several communities and ontologies are being developed. However, to obtain good results when using ontologies in semantically-enabled applications, the ontologies need to be of high quality. One of the quality aspects is that the ontologies should be as complete as possible. In this paper we propose a first version of a tool that supports users in extending ontologies using a phrase-based approach.  To demonstrate the usefulness of our proposed tool, we exemplify the use by extending the Materials Design Ontology.

  • 27.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Armiento, Rickard
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    A First Step towards Extending the Materials Design Ontology2021In: Workshop on Domain Ontologies for Research Data Management in Industry Commons of Materials and Manufacturing - DORIC-MM 2021 / [ed] S Chiacchiera, MT Horsch, J Francisco Morgado, G Goldbeck, 2021, p. 1-11Conference paper (Refereed)
    Abstract [en]

    Ontologies have been proposed as a means towards making data FAIR (Findable, Accessible, Interoperable, Reusable) and has recently attracted much interest in the materials science community. Ontologies for this domain are being developed and one such effort is the Materials Design Ontology. However, to obtain good results when using ontologies in semantically-enabled applications, the ontologies need to be of high quality. One of the quality aspects is that the ontologies should be as complete as possible. In this paper we show preliminary results regarding extending the Materials Design Ontology using a phrase-based topic model.

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  • 28.
    Abd Nikooie Pour, Mina
    et al.
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Database and information techniques. Swedish e-Science Research Centre, Sweden.
    Li, Huanyu
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering. Swedish e-Science Research Centre, Sweden.
    Armiento, Rickard
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Swedish e-Science Research Centre, Sweden.
    Lambrix, Patrick
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering. Swedish e-Science Research Centre, Sweden; University of Gävle, Sweden.
    Phrase2Onto: A Tool to Support Ontology Extension2023In: 27th International Conference on Knowledge Based and Intelligent Information and Engineering Sytems (KES 2023) / [ed] Robert Howlett, Elsevier, 2023, p. 1415-1424Conference paper (Refereed)
    Abstract [en]

    Due to importance of data FAIRness (Findable, Accessible, Interoperable, Reusable), ontologies as a means to make data FAIR have attracted more and more attention in different communities and are being used in semantically-enabled applications. However, to obtain good results while using ontologies in these applications, high quality ontologies are needed of which completeness is one of the important aspects. An ontology lacking information can lead to missing results. In this paper we present a tool, Phrase2Onto, that supports users in extending ontologies to make the ontologies more complete. It is particularly suited for ontology extension using a phrase-based topic model approach, but the tool can support any extension approach where a user needs to make decisions regarding the appropriateness of using phrases to define new concepts. We describe the functionality of the tool and a user study using Pizza Ontology. The user study showed  a good usability of the system and high task completion. Further, we report on a real application where we extend the Materials Design Ontology.

  • 29.
    Abdala, Esraa
    et al.
    Department of Chemical Engineering, University of Khartoum, Khartoum, Sudan.
    Nur, Omer
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Mustafa, Mustafa A.
    Materials and Nanotechnology Research Centre, University of Khartoum, Khartoum, Sudan.
    Efficient Biodiesel Production from Algae Oil Using Ca-Doped ZnO Nanocatalyst2020In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 59, no 43, p. 19235-19243Article in journal (Refereed)
    Abstract [en]

    Biodiesel is a sustainable alternative to petroleum diesel produced by transesterification of vegetable oils in the presence of a catalyst. The present study investigates heterogeneous transesterification of algal oil to biodiesel using novel calcium-doped zinc oxide nanocatalysts synthesized using a UV shaker. The developed catalyst was under different light sources, UV and non-UV; different calcium concentrations (0.01, 0.03, 0.05 M); and different calcination temperatures (600, 700, 800 degrees C). The catalyst has been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and energy-dispersive spectroscopy (EDS). The effects of the different parameters used in catalyst preparation were studied for transesterification of algal oil. The catalyst of 0.05 M calcium loading and 700 degrees C calcination temperature synthesized in UV light is considered as the most suitable nanocatalyst, which achieved 99.18% yield of biodiesel. The catalyst was used three times effectively with 76% yield. The chemical properties of biodiesel have been investigated using gas chromatography (GC).

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  • 30.
    Abdalla, Hassan
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Charge and Energy Transport in Disordered Organic Semiconductors2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Improvement of the performance of organic disordered semiconductors (OSC) is driven by the understanding   of the underlying charge transport mechanisms and systematic exploitation thereof. There exists a multitude of materials and material systems based on polymers and small molecules with promising performance for use in organic light emitting diodes, photovoltaics, organic field-effect transistors and thermoelectrics. However, universal understanding of many classes of these materials has eluded researchers, due to their broad   spectrum of morphologies, molecular structures and electrical properties. Building on the large body of existing models, this thesis deals with charge transport phenomena from the perspective of transport energetics, by studying the interplay between a few but important concepts commonly accepted to play a crucial role in all  OSC materials; energetic disorder, charge carrier hopping and Coulomb interactions. The influence of these concepts on the energetic landscape through which charge carriers move and how this translates to experimentally observed transport phenomena are studied by a combination of experimental work, kinetic Monte Carlo (MC) simulations and empirical and analytical models.

    The universal scaling and collapse of the temperature and electric field dependence of the conductivity of PEDOT:PSS to a single curve is shown to be functionally equivalent to the scaling of the effective temperature, which describes the effect of field heating as a broadening of the charge carrier distribution. From numerical investigation of the energy relaxation, an empirical model is developed that relates the physical meaning   behind both concepts to the heat balance between Joule heating of the carrier distribution via the effective temperature and energy loss to the lattice. For this universal description to be applicable a strongly energy- dependent density of states (DOS) as well as Coulomb interactions and large carrier concentrations are needed.

    Chemical doping is a common way of improving charge transport in OSC and is also beneficial for energy transport, which combined leads to an increased thermoelectric power factor. The ensuing thermoelectric investigations not only showed the potential of these materials for use in thermoelectric generators, but are  also helpful in unraveling charge transport mechanism as they give direct insight into the energetics of a material. Interestingly, doped OSC exhibit the same universal power-law relationship between thermopower and conductivity, independent of material system or doping method, pointing towards a common energy and charge transport mechanism. In this thesis an analytical model is presented, which reproduces said universal power-law behavior and is able to attribute it to Variable Range Hopping (VRH) or a transition between Nearest Neighbour Hopping (NNH) and VRH at higher concentrations. This model builds on an existing three- dimensional hopping formalism that includes the effect of the attractive Coulomb potential of ionized dopants that leads to a broadening of the DOS. Here, this model is extended by including the energy offset between   host and dopant material and is positively tested against MC simulations and a set of thermoelectric measurements covering different material groups and doping mechanisms.

    Organic field effect transistors (OFETs) have become increasingly comparable in electrical mobility to their inorganic (silicon) counterparts. The spatial extent of charge transport in OFETs has been subject to debate since their inception with many experimental, numerical and analytical studies having been undertaken. Here it is shown that the common way of analyzing the dimensionality of charge transport in OFETs may be prone to misinterpretations. Instead, the results in this thesis suggest that charge transport in OFETs is, in fact, quasi- two-dimensional (2D) due to the confinement of the gate field in addition to a morphology-induced preferred in-plane direction of the transport. The inherently large charge carrier concentrations in OFETs in addition to   the quasi-2D confinement leads to increased Coulomb interaction between charge carriers as compared to bulk material, leading to a thermoelectric behavior that deviates from doped organic systems. At very large concentrations interesting charge transport phenomena are observed, including an unexpected simultaneous increase of the concentration dependence and the magnitude of the mobility, the appearance of a negative transconductance, indicating a transition to an insulating Mott-Hubbard phase. The experimental and   numerical results in this thesis relate these phenomena the intricacies of the interplay between Coulomb interactions, energetic disorder and charge carrier hopping.

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  • 31.
    Abdalla, Hassan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Fabiano, Simone
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Kemerink, Martijn
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Investigation of the dimensionality of charge transport in organic field effect transistors2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 95, no 8, article id 85301Article in journal (Refereed)
    Abstract [en]

    Ever since the first experimental investigations of organic field effect transistors (OFETs) the dimensionality of charge transport has alternately been described as two dimensional (2D) and three dimensional (3D). More recently, researchers have turned to an analytical analysis of the temperature-dependent transfer characteristics to classify the dimensionality as either 2D or 3D as well as to determine the disorder of the system, thereby greatly simplifying dimensionality investigations. We applied said analytical analysis to the experimental results of our OFETs comprising molecularly well-defined polymeric layers as the active material as well as to results obtained from kinetic Monte Carlo simulations and found that it was not able to correctly distinguish between 2D and 3D transports or give meaningful values for the disorder and should only be used for quasiquantitative and comparative analysis. We conclude to show that the dimensionality of charge transport in OFETs is a function of the interplay between transistor physics and morphology of the organic material.

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  • 32.
    Abdalla, Hassan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    van de Ruit, Kevin
    Eindhoven University of Technology, Netherlands.
    Kemerink, Martijn
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering. Eindhoven University of Technology, Netherlands.
    Effective Temperature and Universal Conductivity Scaling in Organic Semiconductors2015In: Scientific Reports, E-ISSN 2045-2322, Vol. 5, article id 16870Article in journal (Refereed)
    Abstract [en]

    We investigate the scalability of the temperature-and electric field-dependence of the conductivity of disordered organic semiconductors to universal curves by two different but commonly employed methods; by so-called universal scaling and by using the effective temperature concept. Experimentally both scaling methods were found to be equally applicable to the out-of-plane charge transport in PEDOT: PSS thin films of various compositions. Both methods are shown to be equivalent in terms of functional dependence and to have identical limiting behavior. The experimentally observed scaling behavior can be reproduced by a numerical nearest-neighbor hopping model, accounting for the Coulomb interaction, the high charge carrier concentration and the energetic disorder. The underlying physics can be captured in a simple empirical model, describing the effective temperature of the charge carrier distribution as the outcome of a heat balance between Joule heating and (effective) temperature-dependent energy loss to the lattice.

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  • 33.
    Abdalla, Hassan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Zuo, Guangzheng
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Kemerink, Martijn
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Range and energetics of charge hopping in organic semiconductors2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 24, article id 241202Article in journal (Refereed)
    Abstract [en]

    The recent upswing in attention for the thermoelectric properties of organic semiconductors (OSCs) adds urgency to the need for a quantitative description of the range and energetics of hopping transport in organic semiconductors under relevant circumstances, i.e., around room temperature (RT). In particular, the degree to which hops beyond the nearest neighbor must be accounted for at RT is still largely unknown. Here, measurements of charge and energy transport in doped OSCs are combined with analytical modeling to reach the univocal conclusion that variable-range hopping is the proper description in a large class of disordered OSC at RT. To obtain quantitative agreement with experiment, one needs to account for the modification of the density of states by ionized dopants. These Coulomb interactions give rise to a deep tail of trap states that is independent of the materials initial energetic disorder. Insertion of this effect into a classical Mott-type variable-range hopping model allows one to give a quantitative description of temperature-dependent conductivity and thermopower measurements on a wide range of disordered OSCs. In particular, the model explains the commonly observed quasiuniversal power-law relation between the Seebeck coefficient and the conductivity.

  • 34.
    Abdallah, Nancy
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics.
    Hansson, Mikael
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Hultman, Axel
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Topology of posets with special partial matchings2019In: Advances in Mathematics, ISSN 0001-8708, E-ISSN 1090-2082, Vol. 348, p. 255-276Article in journal (Refereed)
    Abstract [en]

    Special partial matchings (SPMs) are a generalisation of Brentis special matchings. Let a pircon be a poset in which every non-trivial principal order ideal is finite and admits an SPM. Thus pircons generalise Mariettis zircons. We prove that every open interval in a pircon is a PL ball or a PL sphere. It is then demonstrated that Bruhat orders on certain twisted identities and quasiparabolic W-sets constitute pircons. Together, these results extend a result of Can, Cherniaysky, and Twelbeck, prove a conjecture of Hultman, and confirm a claim of Rains and Vazirani.

  • 35.
    Abdallah, Nancy
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Hultman, Axel
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Combinatorial invariance of Kazhdan-Lusztig-Vogan polynomials for fixed point free involutions2018In: Journal of Algebraic Combinatorics, ISSN 0925-9899, E-ISSN 1572-9192, Vol. 47, no 4, p. 543-560Article in journal (Refereed)
    Abstract [en]

    When acts on the flag variety of , the orbits are in bijection with fixed point free involutions in the symmetric group . In this case, the associated Kazhdan-Lusztig-Vogan polynomials can be indexed by pairs of fixed point free involutions , where denotes the Bruhat order on . We prove that these polynomials are combinatorial invariants in the sense that if is a poset isomorphism of upper intervals in the Bruhat order on fixed point free involutions, then for all v amp;gt;= u.

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  • 36.
    Abdel Aziz, Ilaria
    et al.
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering. Univ Basque Country UPV EHU, Spain.
    Gladisch, Johannes
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Griggs, Sophie
    Univ Oxford, England.
    Moser, Maximilian
    Univ Oxford, England.
    Biesmans, Hanne
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Beloqui, Ana
    Univ Basque Country UPV EHU, Spain; Basque Fdn Sci, Spain.
    McCulloch, Iain
    Univ Oxford, England.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Stavrinidou, Eleni
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Drug delivery via a 3D electro-swellable conjugated polymer hydrogel2024In: Journal of materials chemistry. B, ISSN 2050-750X, E-ISSN 2050-7518Article in journal (Refereed)
    Abstract [en]

    Spatiotemporal controlled drug delivery minimizes side-effects and enables therapies that require specific dosing patterns. Conjugated polymers (CP) can be used for electrically controlled drug delivery; however so far, most demonstrations were limited to molecules up to 500 Da. Larger molecules could be incorporated only during the CP polymerization and thus limited to a single delivery. This work harnesses the record volume changes of a glycolated polythiophene p(g3T2) for controlled drug delivery. p(g3T2) undergoes reversible volumetric changes of up to 300% during electrochemical doping, forming pores in the nm-size range, resulting in a conducting hydrogel. p(g3T2)-coated 3D carbon sponges enable controlled loading and release of molecules spanning molecular weights of 800-6000 Da, from simple dyes up to the hormone insulin. Molecules are loaded as a combination of electrostatic interactions with the charged polymer backbone and physical entrapment in the porous matrix. Smaller molecules leak out of the polymer while larger ones could not be loaded effectively. Finally, this work shows the temporally patterned release of molecules with molecular weight of 1300 Da and multiple reloading and release cycles without affecting the on/off ratio.

  • 37.
    Abdel Aziz, Ilaria
    et al.
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Gladisch, Johannes
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Musumeci, Chiara
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Moser, Maximilian
    Univ Oxford, England.
    Griggs, Sophie
    Univ Oxford, England.
    Kousseff, Christina J.
    Univ Oxford, England.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Mcculloch, Iain
    Univ Oxford, England.
    Stavrinidou, Eleni
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Electrochemical modulation of mechanical properties of glycolated polythiophenes2024In: Materials Horizons, ISSN 2051-6347, E-ISSN 2051-6355Article in journal (Refereed)
    Abstract [en]

    Electrochemical doping of organic mixed ionic-electronic conductors is key for modulating their conductivity, charge storage and volume enabling high performing bioelectronic devices such as recording and stimulating electrodes, transistors-based sensors and actuators. However, electrochemical doping has not been explored to the same extent for modulating the mechanical properties of OMIECs on demand. Here, we report a qualitative and quantitative study on how the mechanical properties of a glycolated polythiophene, p(g3T2), change in situ during electrochemical doping and de-doping. The Young's modulus of p(g3T2) changes from 69 MPa in the dry state to less than 10 MPa in the hydrated state and then further decreases down to 0.4 MPa when electrochemically doped. With electrochemical doping-dedoping the Young's modulus of p(g3T2) changes by more than one order of magnitude reversibly, representing the largest modulation reported for an OMIEC. Furthermore, we show that the electrolyte concentration affects the magnitude of the change, demonstrating that in less concentrated electrolytes more water is driven into the film due to osmosis and therefore the film becomes softer. Finally, we find that the oligo ethylene glycol side chain functionality, specifically the length and asymmetry, affects the extent of modulation. Our findings show that glycolated polythiophenes are promising materials for mechanical actuators with a tunable modulus similar to the range of biological tissues, thus opening a pathway for new mechanostimulation devices. This work investigates the changes in the mechanical properties of glycolated polythiophenes induced by electrochemical addressing and by electrolyte concentration, due to its ability to stabilize water.

  • 38.
    Abdelfattah, Ahmed
    et al.
    Univ Mediterranea Reggio Calabria, Italy.
    Malacrinò, Antonino
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wisniewski, Michael
    USDA ARS, WV 25430 USA.
    Cacciola, Santa O.
    Univ Catania, Italy.
    Schena, Leonardo
    Univ Mediterranea Reggio Calabria, Italy.
    Metabarcoding: A powerful tool to investigate microbial communities and shape future plant protection strategies2018In: Biological control (Print), ISSN 1049-9644, E-ISSN 1090-2112, Vol. 120Article in journal (Refereed)
    Abstract [en]

    Microorganisms are the main drivers shaping the functioning and equilibrium of all ecosystems, contributing to nutrient cycling, primary production, litter decomposition, and multi-trophic interactions. Knowledge about the microbial assemblies in specific ecological niches is integral to understanding the assemblages interact and function the function, and becomes essential when the microbiota intersects with human activities, such as protecting crops against pests and diseases. Metabarcoding has proven to be a valuable tool and has been widely used for characterizing the microbial diversity of different environments and has been utilized in many research endeavors. Here we summarize the current status of metabarcoding technologies, the advantages and challenges in utilizing this technique, and how this pioneer approach is being applied to studying plant diseases and pests, with a focus on plant protection and biological control. Current and future developments in this technology will foster a more comprehensive understanding of microbial ecology, and the development of new, innovative pest control strategies.

  • 39.
    Abdel-Halim, Adam
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Danielsson, Max
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Arlitt, Martin
    Univ Calgary, Canada.
    Carlsson, Niklas
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Temporal Analysis of X.509 Revocations and their Statuses2022In: 7TH IEEE EUROPEAN SYMPOSIUM ON SECURITY AND PRIVACY WORKSHOPS (EUROS&PW 2022), IEEE , 2022, p. 258-265Conference paper (Refereed)
    Abstract [en]

    Despite the X509 public key infrastructure (PKI) being essential for ensuring the trust we place in our communication with web servers, the revocation of the trust placed in individual X509 certificates is neither transparent nor well-studied, leaving many unanswered questions. In this paper, we present a temporal analysis of 36 million certificates, whose revocation statuses we followed for 120 days since first being issued. We characterize the revocation rates of different certificate authorities (CAs) and how the rates change over the lifetime of the certificates. We identify and discuss several instances where the status changes from "revoked" to "good", "unauthorized" or "unknown", respectively, before the certificates expiry. This complements prior work that has observed such inconsistencies in some CAs behavior after expiry but also highlight a potentially more severe problem. Our results highlight heterogeneous revocation practices among the CAs.

  • 40.
    Abdella, Juhar Ahmed
    et al.
    UAEU, U Arab Emirates.
    Zaki, N. M.
    UAEU, U Arab Emirates.
    Shuaib, Khaled
    UAEU, U Arab Emirates.
    Khan, Fahad
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    Airline ticket price and demand prediction: A survey2021In: Journal of King Saud University - Computer and Information Sciences, ISSN 1319-1578, Vol. 33, no 4, p. 375-391Article in journal (Refereed)
    Abstract [en]

    Nowadays, airline ticket prices can vary dynamically and significantly for the same flight, even for nearby seats within the same cabin. Customers are seeking to get the lowest price while airlines are trying to keep their overall revenue as high as possible and maximize their profit. Airlines use various kinds of computational techniques to increase their revenue such as demand prediction and price discrimination. From the customer side, two kinds of models are proposed by different researchers to save money for customers: models that predict the optimal time to buy a ticket and models that predict the minimum ticket price. In this paper, we present a review of customer side and airlines side prediction models. Our review analysis shows that models on both sides rely on limited set of features such as historical ticket price data, ticket purchase date and departure date. Features extracted from external factors such as social media data and search engine query are not considered. Therefore, we introduce and discuss the concept of using social media data for ticket/demand prediction. (c) 2019 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

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  • 41.
    Abd-Elmagid, Mohamed A.
    et al.
    Virginia Tech, VA 24061 USA.
    Dhillon, Harpreet S.
    Virginia Tech, VA 24061 USA.
    Pappas, Nikolaos
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    A Reinforcement Learning Framework for Optimizing Age of Information in RF-Powered Communication Systems2020In: IEEE Transactions on Communications, ISSN 0090-6778, E-ISSN 1558-0857, Vol. 68, no 8, p. 4747-4760Article in journal (Refereed)
    Abstract [en]

    In this paper, we study a real-time monitoring system in which multiple source nodes are responsible for sending update packets to a common destination node in order to maintain the freshness of information at the destination. Since it may not always be feasible to replace or recharge batteries in all source nodes, we consider that the nodes are powered through wireless energy transfer (WET) by the destination. For this system setup, we investigate the optimal online sampling policy (referred to as the age-optimal policy) that jointly optimizes WET and scheduling of update packet transmissions with the objective of minimizing the long-term average weighted sum of Age of Information (AoI) values for different physical processes (observed by the source nodes) at the destination node, referred to as the sum-AoI. To solve this optimization problem, we first model this setup as an average cost Markov decision process (MDP) with finite state and action spaces. Due to the extreme curse of dimensionality in the state space of the formulated MDP, classical reinforcement learning algorithms are no longer applicable to our problem even for reasonable-scale settings. Motivated by this, we propose a deep reinforcement learning (DRL) algorithm that can learn the age-optimal policy in a computationally-efficient manner. We further characterize the structural properties of the age-optimal policy analytically, and demonstrate that it has a threshold-based structure with respect to the AoI values for different processes. We extend our analysis to characterize the structural properties of the policy that maximizes average throughput for our system setup, referred to as the throughput-optimal policy. Afterwards, we analytically demonstrate that the structures of the age-optimal and throughput-optimal policies are different. We also numerically demonstrate these structures as well as the impact of system design parameters on the optimal achievable average weighted sum-AoI.

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  • 42.
    Abd-Elmagid, Mohamed A.
    et al.
    Virginia Tech, VA 24061 USA.
    Dhillon, Harpreet S.
    Virginia Tech, VA 24061 USA.
    Pappas, Nikolaos
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    AoI-Optimal Joint Sampling and Updating for Wireless Powered Communication Systems2020In: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 69, no 11, p. 14110-14115Article in journal (Refereed)
    Abstract [en]

    This paper characterizes the structure of the Age of Information (AoI)-optimal policy in wireless powered communication systems while accounting for the time and energy costs of generating status updates at the source nodes. In particular, for a single source-destination pair in which a radio frequency (RF)-powered source sends status updates about some physical process to a destination node, we minimize the long-term average AoI at the destination node. The problem is modeled as an average cost Markov Decision Process (MDP) in which, the generation times of status updates at the source, the transmissions of status updates from the source to the destination, and the wireless energy transfer (WET) are jointly optimized. After proving the monotonicity property of the value function associated with the MDP, we analytically demonstrate that the AoI-optimal policy has a threshold-based structure w.r.t. the state variables. Our numerical results verify the analytical findings and reveal the impact of state variables on the structure of the AoI-optimal policy. Our results also demonstrate the impact of system design parameters on the optimal achievable average AoI as well as the superiority of our proposed joint sampling and updating policy w.r.t. the generate-at-will policy.

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  • 43.
    Abd-Elmagid, Mohamed A.
    et al.
    Virginia Tech, VA 24061 USA.
    Dhillon, Harpreet S.
    Virginia Tech, VA 24061 USA.
    Pappas, Nikolaos
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Online Age-minimal Sampling Policy for RF-powered IoT Networks2019In: 2019 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM), IEEE , 2019Conference paper (Refereed)
    Abstract [en]

    In this paper, we study a real-time Internet of Things (IoT)-enabled monitoring system in which a source node (e.g., IoT device or an aggregator located near a group of IoT devices) is responsible for maintaining the freshness of information status at a destination node by sending update packets. Since it may not always be feasible to replace or recharge batteries in all IoT devices, we consider that the source node is powered by wireless energy transfer (WET) by the destination. For this system setup, we investigate the optimal online sampling policy that minimizes the long-term average Age-of-Information (AoI), referred to as the age-optimal policy. The age-optimal policy determines whether each slot should be allocated for WET or update packet transmission while considering the dynamics of battery level, AoI, and channel state information (CSI). To solve this optimization problem, we model this setup as an average cost Markov Decision Process (MDP). After analytically establishing the monotonicity property of the value function associated with the MDP, the age-optimal policy is proven to be a threshold based policy with respect to each of the system state variables. We extend our analysis to characterize the structural properties of the policy that maximizes average throughput for our system setup, referred to as the throughput-optimal policy. Afterwards, we analytically demonstrate that the structures of the age optimal and throughput-optimal policies are different. We also numerically demonstrate these structures as well as the impact of system design parameters on the optimal achievable average AoI.

  • 44.
    Abd-Elmagid, Mohamed A.
    et al.
    Virginia Tech, VA 24061 USA.
    Pappas, Nikolaos
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Dhillon, Arpreet S.
    Virginia Tech, VA 24061 USA.
    On the Role of Age of Information in the Internet of Things2019In: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 57, no 12, p. 72-77Article in journal (Refereed)
    Abstract [en]

    In this article, we provide an accessible introduction to the emerging idea of Age of Information (AoI) that quantifies freshness of information and explore its possible role in the efficient design of freshness-aware Internet of Things (IoT). We start by summarizing the concept of AoI and its variants with emphasis on the differences between AoI and other well-known performance metrics in the literature, such as throughput and delay. Building on this, we explore freshness-aware IoT design for a network in which IoT devices sense potentially different physical processes and are supposed to frequently update the status of these processes at a destination node (e.g., a cellular base station). Inspired by recent interest, we also assume that these IoT devices are powered by wireless energy transfer by the destination node. For this setting, we investigate the optimal sampling policy that jointly optimizes wireless energy transfer and scheduling of update packet transmissions from IoT devices with the goal of minimizing long-term weighted sum-AoI. Using this, we characterize the achievable AoI region. We also compare this AoI-optimal policy with the one that maximizes average throughput (throughput-optimal policy), and demonstrate the impact of system state on their structures. Several promising directions for future research are also presented.

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  • 45.
    Abdollahi Sani, Negar
    et al.
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Mirbel, Deborah
    Univ Bordeaux, France.
    Fabiano, Simone
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Engquist, Isak
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Brochon, Cyril
    Univ Bordeaux, France.
    Cloutet, Eric
    Univ Bordeaux, France.
    Hadziioannou, Georges
    Univ Bordeaux, France.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    A ferroelectric polymer introduces addressability in electrophoretic display cells2019In: FLEXIBLE AND PRINTED ELECTRONICS, ISSN 2058-8585, Vol. 4, no 3, article id 035004Article in journal (Refereed)
    Abstract [en]

    During the last decades, tremendous efforts have been carried out to develop flexible electronics for a vast array of applications. Among all different applications investigated in this area, flexible displays have gained significant attention, being a vital part of large-area devices, portable systems and electronic labels etc electrophoretic (EP) ink displays have outstanding properties such as a superior optical switch contrast and low power consumption, besides being compatible with flexible electronics. However, the EP ink technology requires an active matrix-addressing scheme to enable exclusive addressing of individual pixels. EP ink pixels cannot be incorporated in low cost and easily manufactured passive matrix circuits due to the lack of threshold voltage and nonlinearity, necessities to provide addressability. Here, we suggest a simple method to introduce nonlinearity and threshold voltage in EP ink display cells in order to make them passively addressable. Our method exploits the nonlinearity of an organic ferroelectric capacitor that introduces passive addressability in display cells. The organic ferroelectric material poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) is here chosen because of its simple manufacturing protocol and good polarizability. We demonstrate that a nonlinear EP cell with bistable states can be produced by depositing a P(VDF-TrFE) film on the bottom electrode of the display cell. The P(VDF-TrFE) capacitor and the EP ink cell are separately characterized in order to match the surface charge at their respective interfaces and to achieve and optimize bistable operation of display pixels.

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  • 46.
    Abdollahi Sani, Negar
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Wang, Xin
    Acreo Swedish ICT AB, Sweden.
    Granberg, Hjalmar
    INNVENTIA AB, Sweden.
    Andersson Ersman, Peter
    Acreo Swedish ICT AB, Sweden.
    Crispin, Xavier
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Dyreklev, Peter
    Acreo Swedish ICT AB, Sweden.
    Engquist, Isak
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Gustafsson, Göran
    Acreo Swedish ICT AB, Sweden.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Flexible Lamination-Fabricated Ultra-High Frequency Diodes Based on Self-Supporting Semiconducting Composite Film of Silicon Micro-Particles and Nano-Fibrillated Cellulose2016In: Scientific Reports, E-ISSN 2045-2322, Vol. 6, no 28921Article in journal (Refereed)
    Abstract [en]

    Low cost and flexible devices such as wearable electronics, e-labels and distributed sensors will make the future "internet of things" viable. To power and communicate with such systems, high frequency rectifiers are crucial components. We present a simple method to manufacture flexible diodes, operating at GHz frequencies, based on self-adhesive composite films of silicon micro-particles (Si-mu Ps) and glycerol dispersed in nanofibrillated cellulose (NFC). NFC, Si-mu Ps and glycerol are mixed in a water suspension, forming a self-supporting nanocellulose-silicon composite film after drying. This film is cut and laminated between a flexible pre-patterned Al bottom electrode and a conductive Ni-coated carbon tape top contact. A Schottky junction is established between the Al electrode and the Si-mu Ps. The resulting flexible diodes show current levels on the order of mA for an area of 2 mm(2), a current rectification ratio up to 4 x 10(3) between 1 and 2 V bias and a cut-off frequency of 1.8 GHz. Energy harvesting experiments have been demonstrated using resistors as the load at 900 MHz and 1.8 GHz. The diode stack can be delaminated away from the Al electrode and then later on be transferred and reconfigured to another substrate. This provides us with reconfigurable GHz-operating diode circuits.

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  • 47.
    Abdul Nazar, Mohamed
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Design of a Gysel Combiner at 100 MHz2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis relates to the design and implementation of a Gysel power combiner consisting of two input ports. The design is implemented using discrete (lumped) components over the conventional transmission line architecture and operates at 100 MHz. Because of the high power requirements for the power combiner, special attention is given to the power handling capabilities of the lumped elements and the other components involved. Simulations of an S-parameter of Gysel power combiner are performed using the Advanced Design System (ADS) from Keysight Technologies. The final design of two-way Gysel power combiner using PCB toroidal inductor was implemented, simulated and optimized at centre frequency of 100 MHz. Satisfactory results were obtained in terms of Insertion loss, Return loss and Port Isolation.

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    Design of a Gysel Combiner at 100 MHz
  • 48.
    Abdulla, Ariyan
    et al.
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    Andersson, Erik
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    Heuristiska algoritmer för schemaläggning i real-tidssystem med hänsyn till data beroenden2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The schedule for the jobs in a real-time system can have a huge impact on how the system behave. Since real-time systems are common in safety applications it is important that the scheduling is done in a valid way. Furthermore, one can enhance the performance of the applications by minimizing data latency and jitter. A challenge is that jobs in real-time systems usually have complex constraints making it too time consuming to minimize data latency and jitter to optimality. The purpose of this report is to investigate the possibility of creating high quality schedules using heuristics, with the goal to keep the computational time under one minute. This will be done by comparing three different algorithms that will be used on real scheduling instances provided by the company Arcticus. The first algorithm is a greedy heuristic, the second one a local search and the third one is a metaheuristic, simulated annealing. The results indicate that the data latency can be reduced whilst keeping the computational time below one minute.

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  • 49.
    Abdulla, Parosh Aziz
    et al.
    Uppsala Univ, Sweden.
    Atig, Mohamed Faouzi
    Uppsala Univ, Sweden.
    Chen, Yu-Fang
    Acad Sinica, Taiwan.
    Phi Diep, Bui
    Uppsala Univ, Sweden.
    Holik, Lukas
    Brno Univ Technol, Czech Republic.
    Rezine, Ahmed
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Rummer, Philipp
    Uppsala Univ, Sweden.
    TRAU : SMT solver for string constraints2018In: PROCEEDINGS OF THE 2018 18TH CONFERENCE ON FORMAL METHODS IN COMPUTER AIDED DESIGN (FMCAD), IEEE , 2018, p. 165-169Conference paper (Refereed)
    Abstract [en]

    We introduce TRAU, an SMT solver for an expressive constraint language, including word equations, length constraints, context-free membership queries, and transducer constraints. The satisfiability problem for such a class of constraints is in general undecidable. The key idea behind TRAU is a technique called flattening, which searches for satisfying assignments that follow simple patterns. TRAU implements a Counter-Example Guided Abstraction Refinement (CEGAR) framework which contains both an under- and an over-approximation module. The approximations are refined in an automatic manner by information flow between the two modules. The technique implemented by TRAU can handle a rich class of string constraints and has better performance than state-of-the-art string solvers.

  • 50.
    Abdulla, Parosh Aziz
    et al.
    Uppsala University.
    Atig, Mohammed Faouzi
    Uppsala University.
    Ganjei, Zeinab
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Rezine, Ahmed
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Zhu, Yunyun
    Uppsala University.
    Verification of Cache Coherence Protocols wrt. Trace Filters2015Conference paper (Refereed)
    Abstract [en]

    We address the problem of parameterized verification of cache coherence protocols for hardware accelerated transactional memories. In this setting, transactional memories leverage on the versioning capabilities of the underlying cache coherence protocol. The length of the transactions, their number, and the number of manipulated variables (i.e., cache lines) are parameters of the verification problem. Caches in such systems are finite-state automata communicating via broadcasts and shared variables. We augment our system with filters that restrict the set of possible executable traces according to existing conflict resolution policies. We show that the verification of coherence for parameterized cache protocols with filters can be reduced to systems with only a finite number of cache lines. For verification, we show how to account for the effect of the adopted filters in a symbolic backward reachability algorithm based on the framework of constrained monotonic abstraction. We have implemented our method and used it to verify transactional memory coherence protocols with respect to different conflict resolution policies.

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