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  • 1.
    A. Almaqtari, Faozi
    et al.
    Department of Accounting Faculty of Business, Economics and Social Development, University Malaysia Terengganu.
    H.S. Farhan, Najib
    Universal Business School, India.
    Yahya Salmony, Monir
    Department of Computer Science Aligarh Muslim University Aligarh, India.
    M. Al-Ahdal, Waleed
    Department of Accounting Faculty of Business, Economics and Social Development, University Malaysia Terengganu.
    Mishra, Nandita
    Linköping University, Department of Management and Engineering, Division of Languages for Specific Purposes. Linköping University, Faculty of Arts and Sciences.
    Earning management estimation and prediction using machine learning: A systematic review of processing methods and synthesis for future research2021In: 2021 International Conference on Technological Advancements and Innovations (ICTAI): IEEE, IEEE, 2021, p. 291-298Conference paper (Refereed)
    Abstract [en]

    The present study highlights earning management optimization possibilities to constrain the events of earning management and financial fraud. Our study investigates the existing stock of knowledge and strand literature available on earning management and fraud detection. It aims to review systematically the methods and techniques used by prior research to determine earning management and fraud detection. The results indicate that prior research in earning management optimization is diverged among several techniques and none of these techniques has provided an ideal optimization for earning management. Further, the results reveal that earning management determinants are complex based on the type and size of business entities which complicate the optimization possibilities. The current research brings useful insights for predicting and optimization of earnings management and financial fraud. The present study has significant implications for policymakers, stock markets, auditors, investors, analysts, and professionals.

  • 2.
    A Atlasov, Kirill
    et al.
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Felici, Marco
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Karlsson, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, The Institute of Technology.
    Gallo, Pascal
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Rudra, Alok
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Dwir, Benjamin
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Kapon, Eli
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    1D photonic band formation and photon localization in finite-size photonic-crystal waveguides2010In: OPTICS EXPRESS, ISSN 1094-4087, Vol. 18, no 1, p. 117-122Article in journal (Refereed)
    Abstract [en]

    A transition from discrete optical modes to 1D photonic bands is experimentally observed and numerically studied in planar photonic-crystal (PhC) L-N microcavities of length N. For increasing N the confined modes progressively acquire a well-defined momentum, eventually reconstructing the band dispersion of the corresponding waveguide. Furthermore, photon localization due to disorder is observed experimentally in the membrane PhCs using spatially resolved photoluminescence spectroscopy. Implications on single-photon sources and transfer lines based on quasi-1D PhC structures are discussed.

  • 3.
    A Herrera, I
    et al.
    Norwegian University Science and Technology NTNU.
    Woltjer, Rogier
    Linköping University, Department of Computer and Information Science, CSELAB - Cognitive Systems Engineering Laboratory. Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, Human-Centered systems.
    Comparing a multi-linear (STEP) and systemic (FRAM) method for accident analysis2010In: RELIABILITY ENGINEERING and SYSTEM SAFETY, ISSN 0951-8320, Vol. 95, no 12, p. 1269-1275Article in journal (Refereed)
    Abstract [en]

    Accident models and analysis methods affect what accident investigators look for, which contributory factors are found, and which recommendations are issued. This paper contrasts the Sequentially Timed Events Plotting (STEP) method and the Functional Resonance Analysis Method (FRAM) for accident analysis and modelling. The main issue addressed in this paper is the comparison of the established multi-linear method STEP with the new systemic method FRAM and which new insights the latter provides for accident analysis in comparison to the former established multi-linear method. Since STEP and FRAM are based on a different understandings of the nature of accidents, the comparison of the methods focuses on what we can learn from both methods, how, when, and why to apply them. The main finding is that STEP helps to illustrate what happened, involving which actors at what time, whereas FRAM illustrates the dynamic interactions within socio-technical systems and lets the analyst understand the how and why by describing non-linear dependencies, performance conditions, variability, and their resonance across functions.

  • 4.
    A Hulten, Maj
    et al.
    University Warwick, Warwick Med Sch, Coventry CV4 7AL, W Midlands England .
    Patel, Suketu
    University Warwick, Department Biol Science, Coventry CV4 7AL, W Midlands England .
    Jonasson, Jon
    Linköping University, Department of Clinical and Experimental Medicine, Molecular and Immunological Pathology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pathology and Clinical Genetics.
    Iwarsson, Erik
    Karolinska University Hospital, Karolinska Institute, Department Mol Med and Surg, Clin Genet Unit, S-17176 Stockholm, Sweden .
    On the origin of the maternal age effect in trisomy 21 Down syndrome: the Oocyte Mosaicism Selection model2010In: Reproduction, ISSN 1470-1626, E-ISSN 1476-3990, Vol. 139, no 1, p. 1-9Article, review/survey (Refereed)
    Abstract [en]

    We have recently documented that trisomy 21 mosaicism is common in human foetal ovaries. On the basis of this observation we propose that the maternal age effect in Down syndrome (DS) is caused by the differential behaviour of trisomy 21 in relation to disomy 21 oocytes during development from foetal life until ovulation in adulthood. in particular, we suggest that trisomy 21 oocytes, lagging behind those that are disomic, may escape the timed pruning of the seven million in foetal life to the 300-400 finally selected for ovulation. The net effect of this preferential elimination will be an accumulation of trisomy 21 oocytes in the ovarian reserve of older women. We here highlight the implications of this Oocyte Mosaicism Selection (OMS) model with respect to the prevalent view that the maternal age effect is complex, dependent on many different biological and environmental factors. We examine conclusions drawn from recent large-scale studies in families, tracing DNA markers along the length of chromosome 21q between parents and DS children, in comparison to the OMS model. We conclude that these family linkage data are equally compatible with the maternal age effect originating from the accumulation of trisomy 21 oocytes with advancing maternal age. One relatively straightforward way to get to grips with what is actually going on in this regard would be to compare incidence of trisomy 21 oocytes (and their pairing configurations) in foetal ovaries with that in oocytes at the meiosis I stage from adult women.

  • 5.
    A. Sani, Negar
    Linköping University, Department of Science and Technology, Physics and Electronics.
    M-PSK and M-QAM Modulation/Demodulation of UWB Signal Using Six-Port Correlator2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nowadays high speed and high data rate communication are highly demanded. Consequently, wideband and high frequency transmitter and receivers should be designed. New transmitters and receivers should also have low power consumption, simple design and low manufacturing price in order to fulfill manufacturers’ requests for mass production. Having all above specifications, six-port correlator is a proper choice to be used as modulator and demodulator in transmitters and receivers.

    In this thesis the six-port correlator is introduced, modeled and simulated using Advanced Design System (ADS) software. A simple six-port transmitter/receiver system with a line of sight link is modeled and analyzed in BER, path length and noise terms. The modulation in this system is QAM, frequency is 7.5 GHz and symbol rate is 500 Msymbol/s.

    Furthermore two methods are proposed for high frequency and high symbol rate M-PSK and M-QAM modulation using six-port correlator. The 7.5 GHz modulators are modeled and simulated in ADS. Data streams generated by pseudo random bit generator with 1 GHz bandwidth are applied to modulators. Common source field effect transistors (FETs) with zero bias are used as controllable impedance termination to apply baseband data to modulator. Both modulators show good performance in M-PSK and M-QAM modulation.

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  • 6.
    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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  • 7.
    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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  • 8.
    Aadde, Emil
    Linköping University, Department of Social and Welfare Studies.
    Visionen om det narkotikafria samhället: En diskursanalys2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna uppsats är att belysa hur visionen om det narkotikafria samhället uppenbarar sig i diskurser som behandlar narkotikamissbruk som socialt problem. Empiriskt material i form av ett policydokument och en debattföljetong har analyserats utifrån ett socialkonstruktivistiskt och diskursanalytiskt perspektiv. Analysen pekar mot att definitionskampen om narkotikamissbruk som socialt problem finns över många diskurser, samtidigt ses visionen om det narkotikafria samhället ofta vara närvarande. En nationell diskurs som kan ses utgå från vad vi som nation anser och vill ha i vårt land. En moraldiskurs som lägger värde i olika beteenden och åsikter. En juridisk och polisiär diskurs som utifrån narkotikas juridiska status ramar in fenomenet och en barn-och ungdomsdiskurs som formulerar narkotikan som det största hotet. Alla dessa kan enligt studien ses som en del i konstruktionen av narkotikamissbruk som socialt problem.

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  • 9.
    Aafjes-van Doorn, Katie
    et al.
    Adelphi University, NY 21402 USA; University of Oxford, England.
    Lilliengren, Peter
    Stockholm University, Sweden.
    Cooper, Angela
    Dalhousie University, Canada.
    Macdonald, James
    Headington Psychotherapy, England.
    Falkenström, Fredrik
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences. Uppsala University, Sweden.
    Patients Affective Processes Within Initial Experiential Dynamic Therapy Sessions2017In: Psychotherapy, ISSN 0033-3204, E-ISSN 1939-1536, Vol. 54, no 2, p. 175-183Article in journal (Refereed)
    Abstract [en]

    Research has indicated that patients in-session experience of previously avoided affects may be important for effective psychotherapy. The aim of this study was to investigate patients in-session levels of affect experiencing in relation to their corresponding levels of insight, motivation, and inhibitory affects in initial Experiential Dynamic Therapy (EDT) sessions. Four hundred sixty-six 10-min video segments from 31 initial sessions were rated using the Achievement of Therapeutic Objectives Scale. A series of multilevel growth models, controlling for between-therapist variability, were estimated to predict patients adaptive affect experiencing (Activating Affects) across session segments. In line with our expectations, higher within-person levels of Insight and Motivation related to higher levels of Activating Affects per segment. Contrary to expectations, however, lower levels of Inhibition were not associated with higher levels of Activating Affects. Further, using a time-lagged model, we did not find that the levels of Insight, Motivation, or Inhibition during one session segment predicted Activating Affects in the next, possibly indicating that 10-min segments may be suboptimal for testing temporal relationships in affective processes. Our results suggest that, to intensify patients immediate affect experiencing in initial EDT sessions, therapists should focus on increasing insight into defensive patterns and, in particular, motivation to give them up. Future research should examine the impact of specific inhibitory affects more closely, as well as between-therapist variability in patients in-session adaptive affect experiencing.

  • 10.
    Aagaard, Kirsten
    et al.
    VIA University College, Denmark.
    Andersson, Per
    Linköping University, Department of Behavioural Sciences and Learning, Education and Adult Learning. Linköping University, Faculty of Educational Sciences.
    Halttunen, Timo
    University of Turku, Finland.
    Hansen, Brian Benjamin
    VIA University College, Denmark.
    Nistrup, Ulla
    VIA University College, Denmark.
    Quality in Validation of Prior Learning: Experiences in researching the practice of the Nordic Model for Quality in Validation of Prior Learning2017In: The Learner at the Centre: Validation of Prior Learning strengthens lifelong learning for all / [ed] Ruud Duvekot, Dermot Coughlan and Kirsten Aagaard, Houten/Aarhus: European Centre Valuation of Prior Learning/ VIA University College , 2017, p. 89-102Chapter in book (Other academic)
    Abstract [en]

    This chapter presents findings from a study of quality work in validation (recognition of prior learning) in three cases in Denmark, Finland, and Sweden. The quality work is based on a Nordic model for quality in validation and the study has an interactive approach.

  • 11.
    Aagaard, Knut E.
    et al.
    Helsingborg Hosp, Sweden; Lund Univ, Sweden.
    Björnsson, Hanna
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Lunsjö, Karl
    Helsingborg Hosp, Sweden.
    Frobell, Richard
    Lund Univ, Sweden.
    No differences in histopathological degenerative changes found in acute, trauma-related rotator cuff tears compared with chronic, nontraumatic tears2022In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 30, no 7, p. 2521-2527Article in journal (Refereed)
    Abstract [en]

    Purpose Acute trauma-related rotator cuff tears are believed to have better healing potential than chronic tears due to less degenerative changes of the tendons. However, the histopathological condition of tendons from trauma-related tears is not well investigated. The purpose of this study was to explore specific histopathological features in tendons from acute trauma-related full-thickness rotator cuff tears and to compare them to findings in tendons from nontraumatic, chronic tears. Methods In a prospective cohort study, 62 previously asymptomatic patients [14 women, median age 61 years (range 42-75)] with trauma-related full-thickness rotator cuff tears were consecutively included. Arthroscopic repair was performed within 30 (median, IQR 25-37) days after the injury. During surgery, tissue biopsies were harvested from the supraspinatus tendons in 53 (86%) of the patients. In addition, similar biopsies were harvested from 10 patients undergoing surgery for chronic tears without history of trauma. All tissue samples were examined by a well-experienced pathologist under light microscope. Tendon degeneration was determined using the Bonar score whereas immunostaining was used for proliferation (Ki67), inflammation (CD45), apoptosis (p53) and haemosiderin staining to study traces of bleeding. Results The median (IQR) Bonar score for the acute trauma-related biopsies was 10.5 (7.5-14.5) compared to 11 (5-12.8) for the control group with no statistically significant difference between the groups. No statistically significant between-group difference was found for the inflammatory index whereas tendons from patients with trauma-related full-thickness rotator cuff tears had statistically significantly higher apoptosis [3.1 (0.5-8.9) vs. 0.1 (0-1.5), p = 0.003] and proliferation [4.0 (1.8-6.9) vs. 0.4 (0-2.0), p = 0.001) indices than those undergoing surgery for chronic tears. Positive haemosiderin staining was found in 34% of tissue samples from patients with trauma-related tears compared to 10% in the control group (n.s). Conclusion This study suggests that there is no difference with regard to degenerative changes between supraspinatus tendons harvested from patients with acute, trauma-related rotator cuff tears and patients with nontraumatic, chronic tears.

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  • 12.
    Aagaard, Knut E.
    et al.
    Helsingborg Hosp, Sweden; Lund Univ, Sweden.
    Lunsjo, Karl
    Helsingborg Hosp, Sweden; Lund Univ, Sweden.
    Adolfsson, Lars
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Frobell, Richard
    Lund Univ, Sweden.
    Björnsson Hallgren, Hanna
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Factors associated with healing failure after early repair of acute, trauma-related rotator cuff tears2023In: Journal of shoulder and elbow surgery, ISSN 1058-2746, E-ISSN 1532-6500, Vol. 32, no 10, p. 2074-2081Article in journal (Refereed)
    Abstract [en]

    Background: Healing failure after rotator cuff repair is a challenging problem. Acute, trauma-related tears are considered a separate entity and are often treated surgically. The aim of this study was to identify factors associated with healing failure in previously asymp-tomatic patients with trauma-related rotator cuff tears treated with early arthroscopic repair. Methods: This study included 62 consecutively recruited patients (23% women; median age, 61 years; age range, 42-75 years) with acute symptoms in a previously asymptomatic shoulder and a magnetic resonance imaging-verified full-thickness rotator cuff tear after shoulder trauma. All patients were offered, and underwent, early arthroscopic repair, during which a biopsy specimen was har-vested from the supraspinatus tendon and analyzed for signs of degeneration. Of the patients, 57 (92%) completed 1-year follow-up and underwent assessment of repair integrity on magnetic resonance images according to the Sugaya classification. Risk factors for heal-ing failure were investigated using a causal-relation diagram where age, body mass index, tendon degeneration (Bonar score), diabetes mellitus, fatty infiltration (FI), sex, smoking, tear location regarding integrity of the rotator cable, and tear size (number of ruptured tendons and tendon retraction) were included and analyzed. Results: Healing failure at 1 year was identified in 37% of patients (n = 21). A high degree of FI of the supraspinatus muscle (P = .01), a tear location including disruption of rotator cable integrity (P = .01), and old age (P = .03) were associated with healing failure. Tendon degeneration as determined by histopathology was not associated with healing failure at 1-year follow-up (P = .63). Conclusion: Older age, increased FI of the supraspinatus muscle, and a tear including disruption of the rotator cable increased the risk of healing failure after early arthroscopic repair in patients with trauma-related full-thickness rotator cuff tears. Level of evidence: Level I; Prospective Cohort Design; Prognosis Study

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  • 13.
    Aagaard, Lise
    et al.
    University of So Denmark, Denmark FKL Research Centre Qual Medical Use, Denmark Danish Pharmacovigilance Research Project DANPREP, Denmark .
    Strandell, Johanna
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Melskens, Lars
    University of Copenhagen, Denmark .
    Petersen, Paw S. G.
    University of Copenhagen, Denmark .
    Holme Hansen, Ebba
    FKL Research Centre Qual Medical Use, Denmark Danish Pharmacovigilance Research Project DANPREP, Denmark University of Copenhagen, Denmark .
    Global Patterns of Adverse Drug Reactions Over a Decade Analyses of Spontaneous Reports to VigiBase (TM)2012In: Drug Safety, ISSN 0114-5916, E-ISSN 1179-1942, Vol. 35, no 12, p. 1171-1182Article in journal (Refereed)
    Abstract [en]

    Background: Although systems to collect information about suspected adverse drug reactions (ADRs) were established in many countries and by the WHO in the 1960s, few studies have examined reported ADRs related to national income. Objective: The aim of the study was to characterize ADRs reported to the WHO-ADR database, VigiBase (TM), and to relate data to national income. Methods: We analysed ADR reports submitted to VigiBase (TM) from 2000 to 2009 with respect to reporting rate, age and sex of patient, type, seriousness and medications. Reports were also analysed with respect to national income level, classified in accordance with the World Bank definition: low, lower-middle, upper-middle and high. Results: We analysed 1 359 067 ADR reports including 3 013 074 ADRs. Overall, 16% of reports were serious and 60% were reported for females. High-income countries had the highest ADR reporting rates (range 3-613 reports/million inhabitants/year) and low-income countries the lowest (range 0-21). Distribution of ADRs across income groups with respect to age group, seriousness and sex was non-significant. Overall, the majority of ADRs were reported for nervous system medications, followed by cardiovascular medicines. Low-income countries reported relatively more ADRs for antiinfectives for systemic use than high-income countries, and high-income countries reported more ADRs for antineoplastic and immunomodulating agents than lower-income groups. Conclusion: This study showed that high-income countries had the highest ADR reporting rates and low-income countries the lowest, with large variations across countries in each group. Significant differences in ADR reporting rates were only found for ADRs of the type skin and subcutaneous tissue disorders and for the therapeutic groups antiinfectives for systemic use and antineoplastic and immunomodulation agents. To strengthen ADR reporting rates, especially in low-income countries, more research is needed about the impact of organizational structures and economic resources of national pharmacovigilance centres and ADR reporting practices on the large variations in ADR reporting rates within income groups.

  • 14.
    Aagard Nielsen, Kurt
    et al.
    Roskilde Universitet, Denmark.
    Svensson, Lennart
    Linköping University, Department of Behavioural Sciences and Learning, Work and Working Life. Linköping University, Department of Behavioural Sciences and Learning, Sociology . Linköping University, HELIX Vinn Excellence Centre. Linköping University, Faculty of Arts and Sciences.
    Action Research and Interactive Research: Beyond pratice and theory2006Book (Other (popular science, discussion, etc.))
  • 15.
    Aagard Nielsen, Kurt
    et al.
    Roskilde Universitet.
    Svensson, Lennart
    Linköping University, Faculty of Arts and Sciences. Linköping University, Department of Behavioural Sciences and Learning, Sociology. Linköping University, Department of Behavioural Sciences and Learning, Work and Working Life.
    How to Learn Action Research2006In: Action Research and Interactive Research: beyond practice and theory / [ed] Kurt Aagaard Nielsen and Lennart Svensson, Hamburg: Shaker Verlag , 2006, p. 389-398Chapter in book (Other academic)
  • 16.
    Aakumiah, Prince Osei
    Linköping University, The Tema Institute, Department of Water and Environmental Studies.
    Water Management and Health in Ghana: Caes Study - Kumasi2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There have been multiple cases of drinking water related diseases in Ghana, particularly the cities. Kumasi, the second largest city is recording high figures of drinking water related diseases. The Ghana water and sewage company is supposed to provide adequate safe drinking water to the people. However, the company has failed to provide this service effectively. Various reasons have been given by the company on its inability to perform efficiently. Meanwhile the government decided lately to privatise water in the cities to facilitate access to quality water through what is called “FULL COST RECOVERY”. This attracted a lot of international companies to Ghana but this has also generated protest and demonstrations. The argument is that these foreign companies are basically profit oriented and considering the fact that most of the affected people are very poor, suggesting they cannot afford it.

    The study is aimed at finding out the relationship between water management and health in the study area and how effective water management through full community participation could help provide adequate safe drinking water. The study was a non-interventional descriptive type using both qualitative and quantitative methods. It was conducted in Kumasi, the second largest city in Ghana. A total of 100 residents from the communities was selected through systematic sampling and interviewed. This includes 86 local residents and 14 key informer interviews. The study also relied on observation as well as some selected literature.

    The results confirmed that drinking water related diseases is on the increase with the most affected people being the poor living in shanty and informal areas of the city. It was also found that most people in the city are willing to render any services to provide safe drinking water. But in relative terms, most of these people are very poor with high percentage of illiterates and may only contribute if there is a good relation and trust among all. It however appears that community participation is a good option for the city provided that stakeholders are made to play effective roles.

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  • 17.
    Aalberg, Laura
    et al.
    National Bureau of Investigation, P.O. Box 285, FIN-01301 Vantaa, Finland.
    Andersson, Kjell
    Swedish National Laboratory of Forensic Science, SKL, SE-581 94 Linköping, Sweden.
    Bertler, Christina
    Swedish National Laboratory of Forensic Science, SKL, SE-581 94 Linköping, Sweden.
    Borén, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Analytical Chemistry .
    Cole, Michael D.
    Forensic Science Unit, University of Strathclyde, 204 George Street, Glasgow, UK.
    Dahlén, Johan
    Swedish National Laboratory of Forensic Science, SKL, SE-581 94 Linköping, Sweden.
    Finnon, Yvonne
    Forensic Science Unit, University of Strathclyde, 204 George Street, Glasgow, UK.
    Huizer, Henk
    Netherlands Forensic Institute, Volmerlaan 17, 2288 GD Rijswijk, The Netherlands.
    Jalava, Kajsa
    National Bureau of Investigation, P.O. Box 285, FIN-01301 Vantaa, Finland.
    Kaa, Elisabet
    Department of Forensic Medicine, University of Aarhus, Skovagervej 2, DK-8240 Risskov, Denmark.
    Lock, Eric
    Netherlands Forensic Institute, Volmerlaan 17, 2288 GD Rijswijk, The Netherlands/Institut de Police Scientifique, University of Lausanne, Batiment de Chimie, CH-1015 Lausanne-Dorigny, Switzerland.
    Lopes, Alvaro
    Laboratorio de Policia Cientifica, Policia Judiciaria, Rua Gomes Freire 174, 1169-007 Lisbon, Portugal.
    Poortman-van-der Meer, Anneke
    Department of Forensic Medicine, University of Aarhus, Skovagervej 2, DK-8240 Risskov, Denmark.
    Sippola, Erkki
    National Bureau of Investigation, P.O. Box 285, FIN-01301 Vantaa, Finland.
    Development of a harmonised method for the profiling of amphetamines: I. Synthesis of standards and compilation of analytical data2005In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 149, no 2-3, p. 219-229Article in journal (Refereed)
    Abstract [en]

    Reference material was synthesised for 21 substances that are frequently present as synthetic impurities, i.e. by-products, in illicitly produced amphetamine. Each of these substances is a typical by-product for at least one of the three approaches most often used to synthesise amphetamine, namely, the Leuckart, the reductive amination of benzyl methyl ketone, and the nitrostyrene routes. A large body of data on the substances was recorded, including the following: mass spectra, ultraviolet spectra, Fourier transform infrared spectra, infrared spectra in gas phase, and 1H NMR and 13C NMR spectra. © 2004 Elsevier Ireland Ltd. All rights reserved.

  • 18.
    Aalberse, Rob C
    et al.
    Amsterdam and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Sanquin Research, University of Amsterdam, Amsterdam, The Netherlands.
    Grüber, Christoph
    Department of Pediatric Pneumology and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
    Ljungman, Margaretha
    Health Agency of Sweden, Solna, Sweden.
    Kakat, Suzan
    Department of Pediatric Pneumology and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
    Wahn, Ulrich
    Department of Pediatric Pneumology and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
    Niggemann, Bodo
    Department of Pediatric Pneumology and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
    Nilsson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Allergy Center.
    Further investigations of the IgE response to tetanus and diphtheria following covaccination with acellular rather than cellular Bordetella pertussis2019In: Pediatric Allergy and Immunology, ISSN 0905-6157, E-ISSN 1399-3038, Vol. 30, no 8, p. 841-847Article in journal (Refereed)
    Abstract [en]

    Background

    It has previously been shown in an uncontrolled study that the IgE response to vaccine antigens is downregulated by co‐vaccination with cellular Bordetella pertussis vaccine.

    Methods

    In the present study, we compared in a controlled trial the humoral immune response to diphtheria toxoid (D) and tetanus toxoid (T) in relation to co‐vaccinated cellular or acellular B pertussis vaccine. IgE, IgG4, and IgG to D and T were analyzed at 2, 7, and 12 months of age in sera of children vaccinated with D and T (DT, N = 68), cellular (DTPw, N = 68), 2‐ or 5‐component acellular B pertussis vaccine (DTPa2, N = 64; DTPa5, N = 65).

    Results

    One month after vaccination, D‐IgE was detected in 10% sera of DTPw‐vaccinated children, whereas vaccination in the absence of whole‐cell pertussis resulted in 50%‐60% IgE positivity. Six months after vaccination, the IgE antibody levels were found to be more persistent than the IgG antibodies. These diphtheria findings were mirrored by those for tetanus. Only minor differences between vaccine groups were found with regard to D‐IgG and T‐IgG. No immediate‐type allergic reactions were observed.

    Conclusion

    Cellular (but not acellular) B pertussis vaccine downregulates IgE to co‐vaccinated antigens in infants. We assume that the absence of immediate‐type allergic reactions is due to the high levels of IgG antibodies competing with IgE antibodies.

  • 19.
    Aaltio, Iiris
    et al.
    School of Economics and Business University of Jyväskylä, Finland.
    Kyrö, PaulaHelsinki School of Economics, Finland.Sundin, ElisabethLinköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Women, Entrepreneurship and Social Capital: A Dialogue and Construction2008Collection (editor) (Other academic)
    Abstract [en]

    This book explores social capital as the multiple relationships between gender, management and entrepreneurship. Human resources are the social capital of a firm and business life, based on trust as well as on expertise, values and cultural diversity. This calls for cross-cultural knowledge and an understanding of gender issues and individual differences in the social capital of the firm and society. The dialogue between women entrepreneurship and social capital theory and research has its special place among other women entrepreneurship books, the number of which has lately increased. It strengthens still in some respect the fragmented voice of women entrepreneurship research by providing a landscape of women entrepreneurs as creators of, and created by, social capital. It indicates how women entrepreneurs appear to have a special position in forming, developing and reorganizing the social capital in the business world. In its eleven chapters, twenty-six researchers representing a variety of disciplines from different parts of the world are presenting findings on diverse aspects of the dialogue between women entrepreneurship and social capital. As a consequence the central concepts, social capital, entrepreneurship and gender, are given a variety of meanings. Women entrepreneurs and business owners regardless of their cultural context, branch and education provide interesting ideas to the global debate on equality and social capital.

  • 20.
    Aalto, Angelika
    et al.
    Linköping University, Department of Culture and Society.
    Kiani, Mina
    Linköping University, Department of Culture and Society.
    En räddare i nöden: En analys av kammarrättens konstruktion av nöd och rätten till nödbistånd2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det finns ingen särskild nödbiståndsparagraf i socialtjänstlagen (SFS 2001:453) [SoL] utan bedömningen av rätten till nödbistånd regleras i samma paragraf som ekonomiskt bistånd, nämligen SoL 4:1. Syftet med denna studie var att analysera på vilket sätt nöd och rätten till nödbistånd konstrueras av kammarrätten. Dessutom avsåg denna studie att undersöka hur rättssäkerheten för enskilda som söker nödbistånd påverkas genom konstruktionerna av nöd och rätten till nödbistånd. Socialkonstruktionism, rättssociologi samt formell rättssäkerhet och materiell rättssäkerhet är de teoretiska perspektiv och begrepp som användes när studiens empiri analyserades. Sammanlagt analyserades 42 rättsfall från kammarrätten med hjälp av kvalitativ innehållsanalys. Under analysprocessens första steg styrde inte studiens teoretiska utgångspunkter de kategorier som togs fram, utan detta gjordes efteråt. Med hjälp av innehållsanalys urskiljdes följande fyra kategorier: Kapital, Livssituation, Eget ansvar och tidsaspekt samt Byråkrati. De första två kategorierna utgör kammarrättens konstruktion av nöd, medan de andra två kategorierna representerar kammarrättens konstruktion av rätten till nödbistånd. 

    Studiens resultat visar bland annat på att kammarrätten konstruerar nöd utifrån den enskildes kapital, där även individens egna livssituation samt föreställningar i samhället kan påverka kammarrättens bedömning om man befinner sig i nöd eller inte. Kammarrättens konstruktion av rätten till nödbistånd fokuserade på den enskildes egna ansvar för sin privatekonomi. Dessutom påverkade antalet nödlägen samt om nödsituationen ansågs självförvållad eller inte huruvida den enskilde beviljades nödbistånd eller inte, kammarrätten förstärker därmed egenansvarsnormen. I denna konstruktion blev det även tydligt att den enskilde behöver bevisa sin nödsituation genom att bifoga relevanta underlag och dokument i sin ansökan. Att det inte finns ett enhetligt sätt att bedöma nöd kopplas till att SoL beskrivs och tolkas som en ramlag. Konstruktionerna påverkar negativt den formella och materiella rättssäkerheten, eftersom studiens resultat visar att kammarrättens beslut och bedömningar inte är förutsägbara eller överensstämmer med de verkliga förhållandena. Denna studie identifierar att avsaknaden av en nödbiståndsparagraf och tillräckligt med prejudicerande domar om nödbistånd gör det svårt för de enskilda och de professionella inom socialt arbete att bedöma när en nödsituation föreligger samt när den stödsökande har rätt till nödbistånd. Studien visar att dessa vägledningar möjligtvis skulle förbättra rättssäkerheten och förenkla ansökningsprocessen för individen, samt även för dem professionella som handlägger och bedömer nödbiståndsansökningar. 

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  • 21.
    Aalto, Anne
    et al.
    Linköping University, Department of Medicine and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Dahlqvist Leinhard, Olof
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences.
    Jaworski, M
    Gustavsson, M
    Tisell, Anders
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Linköping University, Faculty of Health Sciences.
    Landtblom, Anne-Marie
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Clinical and Experimental Medicine, Psychiatry. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Effects of Betainterferon treatment in Multiple Sclerosis Studied by Quantitative 1H MRS2009Conference paper (Other academic)
  • 22.
    Aalto, Anne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Sjoewall, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Immunology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medicine, Department of Infectious Diseases in Östergötland.
    Davidsson, Leif
    Linköping University, Department of Medicine and Care, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Forsberg, Pia
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Infectious Diseases. Östergötlands Läns Landsting, Centre for Medicine, Department of Infectious Diseases in Östergötland.
    Smedby, Örjan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Brain magnetic resonance imaging does not contribute to the diagnosis of chronic neuroborreliosis2007In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, no 7, p. 755-762Article in journal (Refereed)
    Abstract [en]

    Background: Borrelia infections, especially chronic neuroborreliosis ( NB), may cause considerable diagnostic problems. This diagnosis is based on symptoms and findings in the cerebrospinal fluid but is not always conclusive. Purpose: To evaluate brain magnetic resonance imaging ( MRI) in chronic NB, to compare the findings with healthy controls, and to correlate MRI findings with disease duration. Material and Methods: Sixteen well- characterized patients with chronic NB and 16 matched controls were examined in a 1.5T scanner with a standard head coil. T1- ( with and without gadolinium), T2-, and diffusion- weighted imaging plus fluid- attenuated inversion recovery ( FLAIR) imaging were used. Results: White matter lesions and lesions in the basal ganglia were seen in 12 patients and 10 controls ( no significant difference). Subependymal lesions were detected in patients down to the age of 25 and in the controls down to the age of 43. The number of lesions was correlated to age both in patients ( rho=0.83, P < 0.01) and in controls ( rho=0.61, P < 0.05), but not to the duration of disease. Most lesions were detected with FLAIR, but many also with T2- weighted imaging. Conclusion: A number of MRI findings were detected in patients with chronic NB, although the findings were unspecific when compared with matched controls and did not correlate with disease duration. However, subependymal lesions may constitute a potential finding in chronic NB.

  • 23.
    Aalto Hagman, Fredrik
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Sonde, Claes
    Linköping University, Department of Management and Engineering, Business Administration.
    Innovation Crowdsourcing: Exploring the Use of an Innovation Intermediary2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: With the Open Innovation paradigm come new hopes for innovating companies. The ability to tap a global network of experts can, at least in theory, have a significant impact on an organization’s competitive strength. Before such a ‘network of experts’ can be used to its full potential however, a number of challenges related to knowledge markets seem to need solutions. About 10 years ago however, we could witness the entry of a new breed of company – calling themselves innovation intermediaries. These companies are built to profit from delivering the usefulness of knowledge networks to client (Seeker) companies. Though the use of such networks and markets have so far been uncommon outside of high-tech fields they are now starting to be seen used by companies in more mature environments.Purpose: The purpose of this thesis is to examine the collaboration between SCA (a large Swedish corporation) and the innovation intermediary InnoCentive in order to create a better understanding of what kind of benefits can be derived from the use of an innovation intermediary, and how these benefits are best utilized. We also set out to identify relevant limitations of innomediary use and to seek to better understand how using an innomediary can fit a client company’s higher-order activities such as exploration and exploitation.Completion and Results: Our findings include that SCA are using InnoCentive mainly as a tool to solve highly specific problems and/or problems with a low degree of complexity that they encounter in their everyday activities. The challenges related to knowledge markets, we find, are avoided by keeping problem complexity low and problem modularity high for the problems sent out to the network. In addition, InnoCentive’s business model seems to eliminate costly negotiations between Seekers and Solvers. Using this kind of ‘market solution’ however, we argue, will put bounds on the usefulness of the network and makes it mainly suited as a tool for improving an organization’s exploitation capacity.

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  • 24.
    Aaltonen, Kristina E.
    et al.
    Lund University, Sweden.
    Rosendahl, Ann H.
    Lund University, Sweden; Skåne University Hospital, Sweden.
    Olsson, Hans
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Malmstrom, Per
    Lund University, Sweden; Skåne University Hospital, Sweden.
    Hartman, Linda
    Lund University, Sweden; Regional Cancer Centre South, Sweden.
    Ferno, Marten
    Lund University, Sweden.
    Association between insulin-like growth factor-1 receptor (IGF1R) negativity and poor prognosis in a cohort of women with primary breast cancer2014In: BMC Cancer, E-ISSN 1471-2407, Vol. 14, no 794Article in journal (Refereed)
    Abstract [en]

    Background: Resistance towards endocrine therapy is a great concern in breast cancer treatment and may partly be explained by the activation of compensatory signaling pathways. The aim of the present study was to investigate if the insulin-like growth factor-1 receptor (IGF1R) signaling pathway was activated or deregulated in breast cancer patients and to explore if any of the markers were prognostic, with or without adjuvant tamoxifen. This signaling pathway has been suggested to cause estrogen independent cell growth and thus contribute to resistance to endocrine treatment in estrogen receptor (ER) positive breast cancer. Methods: The protein expression of IGF1R, phosphorylated Mammalian Target of Rapamycin (p-mTOR) and phosphorylated S6 ribosomal protein (p-S6rp) were investigated by immunohistochemistry using tissue microarrays in two patient cohorts. Cohort I (N = 264) consisted of mainly postmenopausal women with stage II breast cancer treated with tamoxifen for 2 years irrespective of ER status. Cohort II (N = 206) consisted of mainly medically untreated, premenopausal patients with node-negative breast cancer. Distant disease-free survival (DDFS) at 5 years was used as end-point for survival analyses. Results: We found that lower IGF1R expression was associated with worse prognosis for tamoxifen treated, postmenopausal women (HR = 0.70, 95% CI = 0.52 - 0.94, p = 0.016). The effect was seen mainly in ER-negative patients where the prognostic effect was retained after adjustment for other prognostic markers (adjusted HR = 0.49, 95% CI = 0.29 - 0.82, p = 0.007). Expression of IGF1R was associated with ER positivity (p less than 0.001) in the same patient cohort. Conclusions: Our results support previous studies indicating that IGF1R positivity reflects a well differentiated tumor with low metastatic capacity. An association between lack of IGF1R expression and worse prognosis was mainly seen in the ER-negative part of Cohort I. The lack of co-activation of downstream markers (p-mTOR and p-S6rp) in the IGF1R pathway suggested that the prognostic effect was not due to complete activation of this pathway. Thus, no evidence could be found for a compensatory function of IGF1R signaling in the investigated cohorts.

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  • 25.
    Aamand Grabau, Dorthe
    et al.
    Skåne University Hospital, Sweden .
    Bendahl, Par-Ola
    Lund University, Sweden .
    Ryden, Lisa
    Lund University, Sweden .
    Stål, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Ferno, Marten
    Lund University, Sweden .
    The prevalence of immunohistochemically determined oestrogen receptor positivity in primary breast cancer is dependent on the choice of antibody and method of heat-induced epitope retrieval - prognostic implications?2013In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 52, no 8, p. 1657-1666Article in journal (Refereed)
    Abstract [en]

    Background. Oestrogen receptor (ER) status is important for the choice of systemic treatment of breast cancer patients. However, most data from randomised trials on the effect of adjuvant endocrine therapy according to ER status are based on the cytosol methods. Comparisons with immunohistochemical methods have given similar results. The aim of the present study was to examine whether different ER antibodies and heat-induced epitope retrieval (HIER) methods influence the prevalence of ER-positivity in primary breast cancer. Material and methods. This study is based on patients included in a clinical trial designed to compare the effect of two years of adjuvant tamoxifen versus no adjuvant systemic treatment in premenopausal women. From 1986 to 1991, 564 patients from two study centres in Sweden were enrolled and randomised. Patients were randomised independently of ER status. In the present study, ER status was assessed on tissue microarrays with the three different ER antibody/HIER combinations: 1D5 in citrate pH 6 (n = 390), SP1 in Tris pH 9 (n = 390) and PharmDx in citrate pH 6 (n = 361). Results. At cut-offs of 1% and 10%, respectively, the prevalence of ER-positivity was higher with SP1 (75% and 72%) compared with 1D5 (68% and 66%) and PharmDx (66% and 62%). At these cut-offs, patients in the discordant groups (SP1-positive and 1D5-negative) seem to have a prognosis intermediate between those of the double-positive and double-negative groups. Comparison with the ER status determined by the cytosol-based methods in the discordant group also showed an intermediate pattern. The repeatability was good for all antibodies and cut-offs, with overall agreement andgt;= 93%. Conclusion. The present study shows that the choice of antibody and HIER method influences the prevalence of ER-positivity. We suggest that this be taken into consideration when choosing a cut-off for clinical decision making.

  • 26.
    Aamir, Syed Ahmed
    Linköping University. Linköping University, Department of Electrical Engineering.
    A 65nm, Low Voltage, Fully Differential, SC Programmable Gain Amplifier for Video AFE2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Due to rapid growth of home entertainment consumer market, video technology has been continuously pushed to deliver sharper pictures with higher resolution. This has brought about stringent requirements on the video analog front end, which often coupled with the low power and low voltage regulations had to deal with short channel effects of the deep submicron CMOS processes.

    This thesis presents the design of a fully differential programmable gain amplifier, as a subcircuit of a larger video digitizing IC designed at division of Electronic Systems. The switched capacitor architecture of the PGA does not only buffer the signal, but performs compensation for the sync-tip of analog video signal.

    The pseudo differential OTA eliminates tail current source and maintains high signal swing and has efficient common mode feedforward mechanism. When coupled with a similar stage provides inherent common moode feedback without using an additional SC-CMFB block.

    The PGA has been implemented using a 65 nm digital CMOS process. Expected difficulties in a 1.2 V OTA design make themselves evident in 65 nm, which is why cascaded OTA structures were inevitable for attaining gain specification of 60 dB. Nested Miller compensation with a pole shifting source follower, stabilizes the multipole system. The final circuit attains up to 200 MHz bandwidth and maintains high output swing of 0.85 V. High slew rate and good common mode and power supply rejection are observed. Noise requirements require careful design of input differential stage. Although output source follower stabilized the system, it reduces significant bandwidth and adds to second order non-linearity.

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  • 27.
    Aamir, Syed Ahmed
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Wikner, J Jacob
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    A 1.2-V pseudo-differential OTA with common-mode feedforward in 65-nm CMOS2010In: Proceedings of the 17th IEEE International Conference on Electronics, Circuits, and Systems, Institute of Electrical and Electronics Engineers (IEEE), 2010, p. 29-32Conference paper (Refereed)
    Abstract [en]

    In this work, we describe the implementation of a 1. 2-V pseudo-differential operational transconductance amplifier (OTA) with common-mode feedforward (CMFF) and inher­ent common-mode feedback (CMFB) in a 65-nm, digital CMOS process. The OTA architecture provides an inher­ent CMFB when cascaded OTA structures are utilized andthis work has studied a cascaded amplifier consisting of fourstages. Due to the low-gain using core 65-nm circuit de­vices, the overall gain must be distributed on all four stages to acquire a gain of more than 60 dB, while maintaining a-3-dB bandwidth of 200 MHz. To achieve high gain, we propose using a modified, positive-feedback, cross-coupled input differential stage. The modified OTA achieves a high output swing of ± 0.85 V due to only two stacked transistors, 88 dB DC gain and a third-order harmonic of -60 dB for 800 mVpp at 30 MHz. Further on, in a capacitive buffer configuration, we achieve a high slew rate of 1240 V/µS, -3-dB bandwidth of 509 MHz, signal-to-noise ratio of 63 dB while consuming 10.4 mW power.

  • 28.
    Aamir, Syed Ahmed
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Wikner, J Jacob
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    A 500-MHz low-voltage programmable gain amplifier for HD video in 65-nm CMOS2010In: Proceedings of 28th IEEE Norchip Conference., NORCHIP'10, Tampere: www.ieee.org , 2010, p. 1-4Conference paper (Refereed)
    Abstract [en]

    This work describes the implementation of a 1.2-V programmable gain amplifier (PGA) for high-definition (HD) video digitizers in a 65-nm digital CMOS process. The “pseudo” switched-capacitor (SC) PGA architecture buffers the video signal, without switching, during the active video. The SC circuitry is used for setup of DC operating point during horizontal and vertical blanking periods. Additionally, it compensates for the `sync-tip' of analog video signals to an equal blanking level for increased dynamic range to the digitizer following the PGA. The operational transconductance amplifier (OTA) employed as main amplifier in the PGA is a pseudo-differential, positive-feedback input stage architecture with a common-mode feedforward (CMFF) technique. The common-mode feedback (CMFB) is provided once two OTAs are cascaded. Schematic-level simulation results show that the OTA maintains a -3-dB bandwidth of 550 MHz, while keeping the distortion HD3 at -60 dB for a 30-MHz, 850 mVpp high definition video signal. The 88 dB DC gain is distributed among four OTA stages and the overall, combined PGA achieves a signal-to-noise ratio of 63 dB. Due to only two stacked transistors, it achieves high output swing of ±0.85 V, 1240 V/μs slew rate while consuming 10.4 mW power.

  • 29.
    Aamodt, Ina Thon
    et al.
    Oslo Univ Hosp, Norway; Lovisenberg Diaconal Univ Coll, Norway.
    Lie, Irene
    Oslo Univ Hosp, Norway; Norwegian Univ Sci & Technol, Norway.
    Lycholip, Edita
    Vilnius Univ, Lithuania; Vilnius Univ, Lithuania.
    Strömberg, Anna
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Cardiology in Linköping.
    Jaarsma, Tiny
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences.
    Celutkiene, Jelena
    Vilnius Univ, Lithuania.
    Helleso, Ragnhild
    Univ Oslo, Norway.
    Informal Caregivers Experiences with Performing Telemonitoring in Heart Failure Care at Home-A Qualitative Study2022In: Healthcare, E-ISSN 2227-9032, Vol. 10, no 7, article id 1237Article in journal (Refereed)
    Abstract [en]

    Informal caregivers have an important role in caring for family members at home. Supporting persons with a chronic illness such as heart failure (HF) in managing their self-care is reported to be a challenge and telemonitoring has been suggested to be of support. Aim: to explore informal caregivers experiences with performing non-invasive telemonitoring to support persons with HF at home for 30 days following hospital discharge in Norway and Lithuania. Methods: A qualitative explorative study of informal caregivers performing non-invasive telemonitoring using lung-impedance measurements and short message service (SMS). Data was collected using semi-structured interviews with informal caregivers of persons with HF in NYHA class III-IV in Norway and Lithuania. Results: Nine interviews were conducted with informal caregivers of persons with HF who performed non-invasive telemonitoring at home. A sequential process of three categories emerged from the data: access to support, towards routinizing, and mastering non-invasive telemonitoring. Conclusion: Informal caregivers performed non-invasive telemonitoring for the first time in this study. Their experiences were of a sequential process that included access to support from health care professionals, establishing a routine together, and access to nurses or physicians in HF care as part of mastering. This study highlights involving informal caregivers and persons with HF together in the implementation and future research of telemonitoring in HF care.

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  • 30.
    Aamodt, Ina Thon
    et al.
    Oslo Univ Hosp Ulleval, Norway; Univ Oslo, Norway.
    Lycholip, Edita
    Vilnius Univ, Lithuania.
    Celutkiene, Jelena
    Vilnius Univ, Lithuania.
    Strömberg, Anna
    Linköping University, Department of Medical and Health Sciences, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Atar, Dan
    Oslo Univ Hosp, Norway; Univ Oslo, Norway.
    Falk, Ragnhild Sorum
    Oslo Univ Hosp, Norway.
    von Lueder, Thomas
    Oslo Univ Hosp, Norway.
    Helleso, Ragnhild
    Univ Oslo, Norway.
    Jaarsma, Tiny
    Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences.
    Lie, Irene
    Oslo Univ Hosp Ulleval, Norway.
    Health Care Professionals Perceptions of Home Telemonitoring in Heart Failure Care: Cross-Sectional Survey2019In: Journal of Medical Internet Research, E-ISSN 1438-8871, Vol. 21, no 2, article id e10362Article in journal (Refereed)
    Abstract [en]

    Background: Noninvasive telemonitoring (TM) can be used in heart failure (HF) patients to perform early detection of decompensation at home, prevent unnecessary health care utilization, and decrease health care costs. However, the evidence is not sufficient to be part of HF guidelines for follow-up care, and we have no knowledge of how TM is used in the Nordic Baltic region. Objective: The aim of this study was to describe health care professionals (HCPs) perception of and presumed experience with noninvasive TM in daily HF patient care, perspectives of the relevance of and reasons for applying noninvasive TM, and barriers to the use of noninvasive TM. Methods: A cross-sectional survey was performed between September and December 2016 in Norway and Lithuania with physicians and nurses treating HF patients at either a hospital ward or an outpatient clinic. A total of 784 questionnaires were sent nationwide by postal mail to 107 hospitals. The questionnaire consisted of 43 items with close- and open-ended questions. In Norway, the response rate was 68.7% (226/329), with 57 of 60 hospitals participating, whereas the response rate was 68.1% (310/455) in Lithuania, with 41 of 47 hospitals participating. Responses to the closed questions were analyzed using descriptive statistics, and the open-ended questions were analyzed using summative content analysis. Results: This study showed that noninvasive TM is not part of the current daily clinical practice in Norway or Lithuania. A minority of HCPs responded to be familiar with noninvasive TM in HF care in Norway (48/226, 21.2%) and Lithuania (64/310, 20.6%). Approximately half of the HCPs in both countries perceived noninvasive TM to be relevant in follow-up of HF patients in Norway (131/226, 58.0%) and Lithuania (172/310, 55.5%). For physicians in both countries and nurses in Norway, the 3 most mentioned reasons for introducing noninvasive TM were to improve self-care, to reduce hospitalizations, and to provide high-quality care, whereas the Lithuanian nurses described ability to treat more patients and to reduce their workload as reasons for introducing noninvasive TM. The main barriers to implement noninvasive TM were lack of funding from health care authorities or the Territorial Patient Fund. Moreover, HCPs perceive that HF patients themselves could represent barriers because of their physical or mental condition in addition to a lack of internet access. Conclusions: HCPs in Norway and Lithuania are currently nonusers of TM in daily HF care. However, they perceive a future with TM to improve the quality of care for HF patients. Financial barriers and HF patients condition may have an impact on the use of TM, whereas sufficient funding from health care authorities and improved knowledge may encourage the more widespread use of TM in the Nordic Baltic region and beyond.

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  • 31.
    Aamodt, Ina Thon
    et al.
    Oslo Univ Hosp, Norway; Univ Oslo, Norway.
    Lycholip, Edita
    Vilnius Univ, Lithuania.
    Celutkiene, Jelena
    Vilnius Univ, Lithuania.
    von Lueder, Thomas
    Oslo Univ Hosp, Norway.
    Atar, Dan
    Oslo Univ Hosp, Norway; Univ Oslo, Norway.
    Falk, Ragnhild Sorum
    Oslo Univ Hosp, Norway.
    Helleso, Ragnhild
    Univ Oslo, Norway.
    Jaarsma, Tiny
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences.
    Strömberg, Anna
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Cardiology in Linköping.
    Lie, Irene
    Oslo Univ Hosp, Norway.
    Self-Care Monitoring of Heart Failure Symptoms and Lung Impedance at Home Following Hospital Discharge: Longitudinal Study2020In: Journal of Medical Internet Research, E-ISSN 1438-8871, Vol. 22, no 1, article id e15445Article in journal (Refereed)
    Abstract [en]

    Background: Self-care is key to the daily management of chronic heart failure (HF). After discharge from hospital, patients may struggle to recognize and respond to worsening HF symptoms. Failure to monitor and respond to HF symptoms may lead to unnecessary hospitalizations. Objective: This study aimed to (1) determine the feasibility of lung impedance measurements and a symptom diary to monitor HF symptoms daily at home for 30 days following hospital discharge and (2) determine daily changes in HF symptoms of pulmonary edema, lung impedance measurements, and if self-care behavior improves over time when patients use these self-care monitoring tools. Methods: This study used a prospective longitudinal design including patients from cardiology wards in 2 university hospitals-one in Norway and one in Lithuania. Data on HF symptoms and pulmonary edema were collected from 10 participants (mean age 64.5 years; 90% (9/10) male) with severe HF (New York Heart Association classes III and IV) who were discharged home after being hospitalized for an HF condition. HF symptoms were self-reported using the Memorial Symptom Assessment Scale for Heart Failure. Pulmonary edema was measured by participants using a noninvasive lung impedance monitor, the Cardio Set Edema Guard Monitor. Informal caregivers aided the participants with the noninvasive measurements. Results: The prevalence and burden of shortness of breath varied from participants experiencing them daily to never, whereas lung impedance measurements varied for individual participants and the group participants, as a whole. Self-care behavior score improved significantly (P=.007) from a median of 56 (IQR range 22-75) at discharge to a median of 81 (IQR range 72-98) 30 days later. Conclusions: Noninvasive measurement of lung impedance daily and the use of a symptom diary were feasible at home for 30 days in HF patients. Self-care behavior significantly improved after 30 days of using a symptom diary and measuring lung impedance at home. Further research is needed to determine if daily self-care monitoring of HF signs and symptoms, combined with daily lung impedance measurements, may reduce hospital readmissions.

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  • 32.
    Aamodt, Ina Thon
    et al.
    Oslo Univ Hosp, Norway; Univ Oslo, Norway; Lovisenberg Diaconal Univ Coll, Norway.
    Strömberg, Anna
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Cardiology in Linköping.
    Helleso, Ragnhild
    Univ Oslo, Norway.
    Jaarsma, Tiny
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences.
    Lie, Irene
    Oslo Univ Hosp, Norway.
    Tools to Support Self-Care Monitoring at Home: Perspectives of Patients with Heart Failure2020In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 17, no 23, article id 8916Article in journal (Refereed)
    Abstract [en]

    Self-care monitoring at home can be a challenge for patients with heart failure (HF). Tools that leverage information and communication technology (ICT), comprise medical devices, or have written material may support their efforts at home. The aim of this study was to describe HF patients experiences and their prioritization of tools that support, or could support, self-care monitoring at home. A descriptive qualitative design employing semi-structured interviews was used with HF patients living at home and attending an HF outpatient clinic in Norway. We used a deductive analysis approach, using the concept of self-care monitoring with ICT tools, paper-based tools, medical devices, and tools to consult with healthcare professionals (HCPs) as the categorization matrix. Nineteen HF patients with a mean age of 64 years participated. ICT tools are used by individual participants to identify changes in their HF symptoms, but are not available by healthcare services. Paper-based tools, medical devices, and face-to-face consultation with healthcare professionals are traditional tools that are available and used by individual participants. HF patients use traditional and ICT tools to support recognizing, identifying, and responding to HF symptoms at home, suggesting that they could be used if they are available and supplemented by in-person consultation with HCPs.

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  • 33.
    Aanaes, K
    et al.
    Rigshosp, Denmark .
    Rasmussen, N
    Rigshosp, Denmark Statens Serum Institute, Denmark .
    Pressler, T
    Rigshosp, Denmark Rigshosp, Denmark .
    Segelmark, Mårten
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Nephrology UHL.
    Johansen, H K
    Rigshosp, Denmark .
    Lindberg, U
    Lund University, Sweden .
    Hoiby, N
    Rigshosp, Denmark .
    Carlsson, M
    Lund University, Sweden .
    Wieslander, J
    EuroDiagnostica AB, Sweden .
    Buchwald, C
    Rigshosp, Denmark .
    Extensive Endoscopic Image-Guided Sinus Surgery Decreases BPI-ANCA in Patients with Cystic Fibrosis2012In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 76, no 6, p. 573-579Article in journal (Refereed)
    Abstract [en]

    Antineutrophil cytoplasm autoantibodies (ANCA) directed against bactericidal/permeability-increasing protein (BPI) are common in patients with cystic fibrosis (CF), and serum levels are correlated with lung colonization by Pseudomonas aeruginosa and the severity of lung damage. The production of BPI-ANCA may be due to the costimulation of BPI when mounting an immune response against P. aeruginosa. The effect of surgery aiming to eradicate bacteria and infected tissue on BPI-ANCA levels is sparsely described. A cohort of patients with CF were included: 53 patients having extensive image-guided sinus surgery (EIGSS) with topical postoperative antibiotic treatment, 131 non-operated controls and 36 who had double lung transplantation (LTX). In all 219 patients, serum samples before and after surgery or at similar intervals were analysed for IgG and IgA BPI-ANCA. The EIGSS group showed a highly significant decrease in both IgA and IgG BPI-ANCA levels compared with their own preoperative values and control group values (P andlt; 0.0010.02). The LTX patients also showed a highly significant decrease in both IgA and IgG BPI-ANCA levels (P andlt; 0.001). EIGSS and LTX decrease IgA and IgG BPI-ANCA levels in patients with CF, indicating that extensive removal of infected tissue influences the pathogenic process of autoantibody production. The results shown herein are in favour of applying EIGSS in selected patients with CF and for using BPI-ANCA as a surrogate marker for guiding further therapeutic interventions.

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  • 34.
    Aarao, J
    et al.
    University of South Australia.
    Bradshaw-Hajek, B H
    University of South Australia.
    Miklavcic, Stan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Ward, D A
    University of South Australia.
    Numerical implementation of the EDEM for modified Helmholtz BVPs on annular domains2011In: JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN 0377-0427, Vol. 235, no 5, p. 1342-1353Article in journal (Refereed)
    Abstract [en]

    In a recent paper by the current authors a new methodology called the Extended-Domain-Eigenfunction-Method (EDEM) was proposed for solving elliptic boundary value problems on annular-like domains. In this paper we present and investigate one possible numerical algorithm to implement the EDEM. This algorithm is used to solve modified Helmholtz BVPs on annular-like domains. Two examples of annular-like domains are studied. The results and performance are compared with those of the well-known boundary element method (BEM). The high accuracy of the EDEM solutions and the superior efficiency of the EDEM over the BEM, make EDEM an excellent alternate candidate to use in the animation industry, where speed is a predominant requirement, and by the scientific community where accuracy is the paramount objective.

  • 35.
    Aarao, J
    et al.
    University of South Australia.
    Bradshaw-Hajek, B H
    University of South Australia.
    Miklavcic, Stan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Ward, D A
    University of South Australia.
    The extended-domain-eigenfunction method for solving elliptic boundary value problems with annular domains2010In: JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL, ISSN 1751-8113, Vol. 43, no 18, p. 185202-Article in journal (Refereed)
    Abstract [en]

    Standard analytical solutions to elliptic boundary value problems on asymmetric domains are rarely, if ever, obtainable. In this paper, we propose a solution technique wherein we embed the original domain into one with simple boundaries where the classical eigenfunction solution approach can be used. The solution in the larger domain, when restricted to the original domain, is then the solution of the original boundary value problem. We call this the extended-domain-eigenfunction method. To illustrate the methods strength and scope, we apply it to Laplaces equation on an annular-like domain.

  • 36.
    Aarao, J
    et al.
    University of S Australia, Australia .
    Miklavcic, Stan J.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Ward, D A.
    University of S Australia, Australia .
    Extended-domain-eigenfunction method (EDEM): a study of ill posedness and regularization2013In: Journal of Physics A: Mathematical and Theoretical, ISSN 1751-8113, E-ISSN 1751-8121, Vol. 46, no 8Article in journal (Refereed)
    Abstract [en]

    The extended-domain-eigenfunction method (EDEM) proposed for solving elliptic boundary value problems on annular-like domains requires an inversion process. The procedure thus represents an ill-posed problem, whose numerical solution involves an ill-conditioned system of equations. In this paper, the ill-posed nature of EDEM is studied and numerical solutions based on regularization schemes are considered. It is shown that the EDEM solution methodology lends itself naturally to a formulation in terms of the well-known iterative Landweber method and the more general and faster converging semi-iterative regularization schemes. Theoretical details and numerical results of the regularization schemes are presented for the case of the two-dimensional Laplace operator on annular domains.

  • 37.
    Aardal, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ann-Charlotté, Holm
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Cortisol in Saliva: Reference Ranges and Relation to Cortisol in Serum1995In: European Journal of Clinical Chemistry and Clinical Biochemistry, ISSN 0939-4974, Vol. 33, p. 927-932Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to establish morning and evening reference ranges for cortisol in saliva. Another objective was to compare the concentrations of the mainly free cortisol in saliva to those of total cortisol in serum as determined with a commercial radioimmunoassay. The concentrations were determined in matched samples of saliva and serum collected at 8am and 10pm from 197 healthy volunteers. The saliva samples were stable for at least 7 days at room temperature and for 9 months at —20 °C. Reference ranges, the central 95%, were estimated to 3.5—27.0 nmol/1 at 8 am and < 6.0 nmol/1 at 10 pm. The intra-assay coefficient of variation (CV) was below 5% and total CV below 10%. The relation between the cortisol concentrations in serum and saliva was nonlinear with r = 0.86 for serum concentrations < 450 nmol/1 and r = 0.44 for serum concentrations ^ 450 nmol/1. In conclusion, the satisfactory precision of the analysis and the simple non-invasive sampling procedure suggest that saliva may be used for cortisol measurements in situations where blood sampling is difficult to perform.

  • 38.
    Aardal-Eriksson, Elisabeth
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol and posttraumatic stress reactions: methodological and applied studies before and after trauma2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The field of psychotraumatology has its roots in ancient history. During the past decades, the surveillance of the psychobiological background of reactions to and consequences of traumatic stress has made great progress and the complexity of the human stress response system stands out. The hypothalamic-pituitary-adrenocortical axis activity, modulated by various neuroimmunological substances, seems to play a major role in the stress response. However, there are still inconsistencies in explanations of relationships between biological and psychological changes following traumatic stress. Moreover, the matter of predictive factors for the development of posttraumatic morbidity is still in a speculative phase.

    The aims of the present thesis were to further develop a commercial serum cortisol radioimmunoassay (RIA) for determination of cortisol in saliva and to test its reliability, specificity and sensitivity as a biochemical assay. The saliva sampling procedures and sample storage stability were also to be tested. Further issues were to investigate determinations of salivary cortisol and serum prolactin in relation to selfratings of posttraumatic psychological distress and general psychological health. Possible predictive and concurrent validity of salivary cortisol as a biochemical marker for posttraumatic psychological distress were to be tested.

    Cortisol is present in saliva mainly in non-protein form, representing the free, biologically active fraction of the total plasma cortisol concentration. In a first phase of the present thesis, the commercial serum cortisol RIA was modified for determination of cortisol in saliva. The relation between salivary and serum cortisol concentrations was tested. Reference ranges at 8 AM and 10 PM for the salivary cortisol assay were established from 195 healthy subjects. Salivary cortisol concentrations were tested in relation to serum cortisol in estimating adrenocortical function during endocrine dynamic function tests in 37 patients and 13 healthy controls. In testing salivary cortisol as a marker for stress for fieldwork use, a screening study was performed on 66 male rescue workers. Salivary cortisol at 8 AM and 10 PM and serum prolactin were determined and general psychological health and posttraumatic psychological distress were estimated with the self-rating scales General Health Questionnaire, Impact of Event Scale and Posttraumatic Symptom Scale. These scales were used in the second phase of the thesis. Three applied follow-up studies were performed with sampling of salivary cortisol and self-ratings: (a) a study of 31 UN-soldiers five days, two and nine months after a mine accident; (b) a study of 145 UN-soldiers before, at return, and two and six month after a six month mission. (c) a study of 101 UN-soldiers six and twelve months after a six month mission with severe combat exposure.

    The results from the present thesis indicate that the modified method of salivary cortisol determination possesses sufficient precision, accuracy, sample storage stability and procedural advantages for laboratory, clinical and field application. Moreover, it possesses moderate predictive information and moderate to high concurrent validity as a biochemical marker for posttraumatic psychological distress.

  • 39.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Pre-trauma Salivary Cortisol Levels and General Health Ratings in Relation to Post-trauma Changes in Cortisol and Psychological Distress after UN-service in BosniaManuscript (preprint) (Other academic)
    Abstract [en]

    Background: The psychobiology of post-traumatic distress is known to some extent, however the pre-trauma psychobiology is not. The aims of the present study were to relate pre- and post-trauma salivary cortisol levels and general health to post-traumatic distress in a Swedish UN-battalion in Bosnia.

    Methods: Salivary 8 AM and I 0 PM cortisol levels and "General Health Questionnaire" ratings were collected from 145 subjects before the six months' mission, at return and two and six months after mission. During follow-up, the ratings were extended by the "Impact of Events Scale" (IES) and "Post Traumatic Symptom Scale".

    Results: Low pre-trauma morning and evening salivary cortisol levels were statistically significantly related to high scores in all rating scales six months after mission and to increasing IES scores during follow-up. Low morning and high evening post-trauma salivary cortisol levels were related to high ratings of psychological distress six months after mission

    Conclusions: Pre-trauma salivary cortisol levels seem to be related to posttrauma psychological distress, however not to the extent that salivary cortisol levels in a simple way could be used for predictive screening.

  • 40.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol, posttraumatic stress symptoms, and general health in the acute phase and during 9-month follow-up2001In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 50, no 12, p. 986-993Article in journal (Refereed)
    Abstract [en]

    Background: Because traumatic events are unpredictable, there are few studies of psychobiological states immediately following such events. Our study aimed to determine the relation of salivary cortisol to psychologic distress immediately after a traumatic event and then during follow-up.

    Methods: Measurement of morning and evening salivary cortisol and ratings of psychologic distress (using the Impact of Events Scale [IES], the Post Traumatic Symptom Scale, and the General Health Questionnaire) were performed with 31 United Nations soldiers at three time points—5 days and 2 and 9 months—following a mine accident in Lebanon.

    Results: Five days after the accident, 15 subjects reported substantial posttraumatic distress according to the IES, as well as significantly lower morning and higher evening cortisol levels compared with the low-impact group. Within 9 months, the posttraumatic distress of the high-impact group was reduced, accompanied by an increase in morning and a decrease in evening cortisol levels. There were significant relationships between evening cortisol and all rating scales at the first and third time points.

    Conclusions: Subclinical posttraumatic stress following an adverse event can be measured biologically via salivary cortisol levels soon after the event.

  • 41.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Twelve Months Follow-up of Salivary Cortisol in Relation to Psychological Distress and General Health in Swedish UN-personnel after Severe Combat Exposure during Six Months Mission in BosniaManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Our group has presented evidence of relationships between salivary cortisol levels and psychological distress before, during and after trauma-related stress. The aim of the present study was to confirm the part of evidence of relationships between salivary cortisol and posttraumatic distress and their change over time.

    Methods: Salivary cortisol levels at 8 AM and 10 PM and self-ratings were collected from 106 subjects six and twelve months after a six months UNmission in Bosnia. The rating instruments were the "Impact of Event Scale" (IES), the "Post Traumatic Symptom Scale" and the "General Health Questionnaire".

    Results: Significant statistical interactions were found between changes in mean cortisol levels and IES scores over time. Decreasing evening cortisol levels over time were significantly related to decreasing IES scores and vice versa. Morning cortisol levels showed negative, and evening cortisol positive correlations with all rating scores.

    Conclusions: The evidence from previous studies on trauma related stress, that salivary cortisol is related to the development of posttraumatic stress reactions, the morning cortisol in reverse (negative) direction to that (positive) of evening cortisol, were confirmed.

  • 42.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Holm, Ann-Charlotte
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lundin, Tom
    Department of Psychiatry, Uppsala Academic Hospital, Uppsala University, Uppsala (TL), Sweden.
    Salivary cortisol and serum prolactin in relation to stress rating scales in a group of rescue workers1999In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 46, no 6, p. 850-855Article in journal (Refereed)
    Abstract [en]

    Background: Rescue service personnel are often exposed to traumatic events as part of their occupation, and higher prevalence rates of psychiatric illness have been found among this group.

    Methods: In 65 rescue workers, salivary cortisol at 8 am and 10 pm and serum prolactin at 8 am were related to the psychiatric self-rating scale General Health Questionnaire (GHQ-28) measuring psychiatric health, and the Impact of Events Scale (IES) and Post Traumatic Symptom Scale (PTSS) measuring posttraumatic symptoms.

    Results: Seventeen percent of the study population scored above the GHQ-28 cut-off limit but none scored beyond the cut-off limit in the IES and PTSS questionnaires. Salivary cortisol concentration at 10 pm correlated with statistical significance to anxiety (p < .005) and depressive symptoms (p < .01) measured with GHQ-28, as well as to posttraumatic symptoms, with avoidance behavior measured with IES (p < .01) and PTSS (p < .005). Two of the rescue workers were followed over time with the same sampling procedure after a major rescue commission.

    Conclusions: The correlation between evening salivary cortisol and anxiety, depressiveness, and posttraumatic avoidance symptoms indicates that these parameters can be used in screening and follow-up after traumatic stress events.

  • 43.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion.
    Holm, AC
    Eriksson, TE
    Lundin, T
    Linkoping Univ, Fac Hlth Sci, Dept Biomed & Surg, Ctr Clin Chem, S-58185 Linkoping, Sweden.
    Thorell, Lars-Håkan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Psychiatry . Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Psychiatry.
    Salivary cortisol and posttraumatic stress reactions methodological and applied studies before and after trauma2002In: International Journal of Psychophysiology, ISSN 0167-8760, E-ISSN 1872-7697, Vol. 45, no 1-2, p. 89-89Conference paper (Other academic)
  • 44.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Karlberg, Bengt E.
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Holm, Ann-Charlotte
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol: an alternative to serum cortisol determinations in dynamic function tests1998In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 36, no 4, p. 215-222Article in journal (Refereed)
    Abstract [en]

    Salivary cortisol was measured as an alternative to serum cortisol as a marker for adrenocortical function following insulin tolerance test, corticotropin-releasing-hormone stimulation and adreno-corticotrophic hormone stimulation. During insulin tolerance test and corticotropin-releasing-hormone stimulation adreno-corticotrophic hormone was also measured. The tests were performed on healthy control subjects as well as on patients under investigation for various disturbances in the hypothalamic-pituitary-adrenocortical axis (insulin tolerance test: 3 controls on two occasions and 14 patients; corticotropin-releasing-hormone stimulation: 4 controls and 18 patients; adreno-corticotrophic hormone stimulation: 6 controls and 10 patients). Five patients underwent both insulin tolerance test and corticotropin-releasing-hormone stimulation. Using criteria for adequate cortisol response in serum, the patients were classified as good or poor responders. In 42 of the 45 tests performed the same conclusion as to cortisol status was drawn when based on serum and salivary cortisol responses. In healthy subjects and good responders the mean cortisol relative increase was greater in saliva than in serum in all three tests (p < 0.05). Characteristic of the results for the insulin tolerance test was a significant initial mean decrease (p < 0.05), not found in serum, and the highest observed salivary cortisol value was delayed for at least 30 minutes compared to that in serum. Plasma adreno-corticotrophic hormone correlated significantly with the cortisol concentrations determined 15 minutes later in serum (r = 0.54–0.64) and in saliva (r = 0.76–0.85). The more pronounced cortisol response in saliva than in serum and its closer correlation with adreno-corticotrophic hormone offer advantages over serum cortisol, suggesting salivary cortisol measurement may be used as an alternative parameter in dynamic endocrine tets.

  • 45.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Mobäck, Caroline
    Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Jakobsson, Sandra
    Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry. Germany.
    Hoffmann, Johannes J. M. L.
    Abbott GmbH and Co KG, Germany.
    Iron depletion in blood donors - Have extended erythrocyte and reticulocyte parameters diagnostic utility?2015In: Transfusion and apheresis science, ISSN 1473-0502, E-ISSN 1878-1683, Vol. 53, no 1, p. 76-81Article in journal (Refereed)
    Abstract [en]

    Background: Blood donation is associated with iron depletion, but donor iron status is not usually investigated, as such tests are cumbersome and costly. It would therefore be desirable to have simple, fast and inexpensive tests that give information on a donors risk of developing iron depletion. In a pilot study we investigated whether novel erythrocyte and reticulocyte parameters can serve this goal. Methods: In regular blood donors extended red cell parameters were measured using the Abbott CELL-DYN Sapphire hematology analyzer and conventional biochemical tests of iron status. Donors were compared with a regionally matched group of non-donating controls. Results: In the controls, the reference ranges of extended RBC parameters were well comparable to published data. Donors had significantly more microcytic RBC than controls (median 0.9 vs 0.6%), lower serum ferritin concentration (median 43 vs 91 mg/L) and higher soluble transferrin receptor/ferritin index (median 1.60 vs 1.27). Overall 18-28% of the donors were iron depleted. Moreover, 3.3% of donors had iron-restricted erythropoiesis. Microcytic RBC and reticulocyte mean cell hemoglobin content predicted iron depletion with 70% and 64% sensitivities and specificities of 72% and 78%, respectively. When combined these two parameters increased the sensitivity to 82%. Conclusions: Our results in Swedish blood donors confirm a high prevalence of iron depletion, despite iron supplementation used by about half of the donors. Microcytic RBC and MCHr appeared to be helpful in identifying iron-depleted donors, who might benefit from iron supplementation. We recommend larger prospective investigations in order to confirm and extend the findings of this pilot study. (C) 2015 Elsevier Ltd. All rights reserved.

  • 46.
    Aarnio, Annika
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Kimber, Ellen
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Talent Management & Strategy: Identifying Patterns through a Multiple Case Study2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background

    Exploring the Talent Management literature to understand the importance of Talent Management to strategy and the role the view on talent plays in consideration to Talent Management.

    Purpose

    The purpose of this thesis is to increase the empirical research on Talent Management to enable a creation of a conceptual framework.

    Methodology

    A multiple case study approach was taken, as 11 companies from diverse industries, sizes, backgrounds etc. was studied in order to gain a broader picture on the research topic. Furthermore, qualitative data collection method was used and main source of empirical data was interviews conducted with HR professionals of each case company.

    Findings

    The empirical findings indicated there to be a relationship between the strategy and the view on talent. There was further an indication that this relationship has an effect on the focus of the Talent Management activities. 

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  • 47.
    Aarnio, Harri
    et al.
    Abo Akad University.
    Sehati, Parisa
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry.
    Braun, Slawomir
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, The Institute of Technology.
    Nyman, Mathias
    Abo Akad University.
    de Jong, Michel P
    University of Twente.
    Fahlman, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, The Institute of Technology.
    Osterbacka, Ronald
    Abo Akad University.
    Spontaneous Charge Transfer and Dipole Formation at the Interface Between P3HT and PCBM2011In: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 1, no 5, p. 792-797Article in journal (Refereed)
    Abstract [en]

    In the pursuit of developing new materials for more efficient bulk-heterojunction solar cells, the blend poly (3-hexylthiophene):[ 6,6]-phenyl-C(61)-butyric acid methyl ester (P3HT:PCBM) serves as an important model system. The success of the P3HT: PCBM blend comes from efficient charge generation and transport with low recombination. There is not, however, a good microscopic picture of what causes these, hindering the development of new material systems. In this report UV photoelectron spectroscopy measurements on both regiorandom-(rra) and regioregular-(rr) P3HT are presented, and the results are interpreted using the Integer Charge Transfer model. The results suggest that spontaneous charge transfer from P3HT to PCBM occurs after heat treatment of P3HT: PCBM blends. The resulting formation of an interfacial dipole creates an extra barrier at the interface explaining the reduced (non-)geminate recombination with increased charge generation in heat treated rr-P3HT: PCBM blends. Extensive photoinduced absorption measurements using both above-and below-bandgap excitation light are presented, in good agreement with the suggested dipole formation.

  • 48.
    Aarnio, Linus
    Linköping University, Department of Computer and Information Science.
    Confidence in Release Candidates: Maintaining confidence levels when moving from traditional release management to continuous delivery2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When shortening release cycles and moving towards continuous delivery, a different approach for quality assurance may be needed than in traditional release management. To allow the transition, all stakeholders must retain a sense of confidence in the quality of release candidates. This thesis proposes a definition for confidence consisting of 30 confidence factors to take into account to ensure confidence from all stakeholders. Confidence factors have been found through interviews with 11 stakeholders, analyzed and categorized using grounded theory analysis. The found factors are grouped into two main categories: Process and Verification Results.

    The thesis additionally contains a literature review of quality measurements and explores how confidence can be expressed in a continuous delivery pipeline. It is found that it is not possible to comprehensively express confidence only with metrics displayable in a pipeline when including only currently well-researched metrics, but with the combination of processes known to be followed in the organization some metrics provide coverage for many of the confidence factors.

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  • 49.
    Aarnivala, Henri
    et al.
    Oulu Univ Hosp, Finland; Univ Oulu, Finland.
    Giertz, Mia
    Uppsala Univ Hosp, Sweden; Uppsala Univ, Sweden.
    Michelsen, Sascha Wilk
    Univ Hosp Rigshospitalet, Denmark.
    Björklund, Caroline
    Umeå Univ Hosp, Sweden.
    Englund, Annika
    Uppsala Univ Hosp, Sweden; Uppsala Univ, Sweden.
    Gronroos, Marika
    Turku Univ Hosp, Finland.
    Hjalgrim, Lisa Lyngsie
    Univ Hosp Rigshospitalet, Denmark.
    Huttunen, Pasi
    Univ Helsinki, Finland.
    Niinimäki, Tuukka
    Univ Oulu, Finland; Oulu Univ Hosp, Finland.
    Penno, Eva
    Uppsala Univ Hosp, Sweden.
    Pokka, Tytti
    Oulu Univ Hosp, Finland.
    Pöyhönen, Tuuli
    Kuopio Univ Hosp, Finland.
    Raittinen, Päivi
    Tampere Univ, Finland.
    Ranta, Susanna
    Karolinska Univ Hosp, Sweden; Karolinska Inst, Sweden.
    Svahn, Johan E.
    Lund Univ, Sweden.
    Törnudd, Lisa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Children's and Women's Health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, H.K.H. Kronprinsessan Victorias barn- och ungdomssjukhus.
    Harila, Arja
    Uppsala Univ, Sweden.
    Niinimäki, Riitta
    Oulu Univ Hosp, Finland; Univ Oulu, Finland.
    Radiological follow-up of osteonecrosis lesions in children and adolescents with Hodgkin lymphoma2024In: British Journal of Haematology, ISSN 0007-1048, E-ISSN 1365-2141, Vol. 205, no 4, p. 1460-1468Article in journal (Refereed)
    Abstract [en]

    Osteonecrosis (ON) is a common complication of glucocorticoid-based Hodgkin lymphoma (HL) treatment, but the natural evolution and prognosis of ON lesions remain poorly understood. We describe the radiological evolution of ON lesions identified in a Nordic population-based cohort of paediatric HL patients. Magnetic resonance images of suspected ON lesions were centrally reviewed to confirm ON diagnosis and grade the ON lesions according to the Niinim & auml;ki classification. The study included 202 ON lesions in 46 patients, of which 77 were joint lesions. Follow-up images were available for 146/202 lesions, with a mean follow-up time of 28 months. During follow-up, 71% of the lesions remained stable, 26% improved or resolved, and 3% progressed. A higher ON grade at diagnosis was associated with a lower likelihood of spontaneous resolution. The likelihood for resolution of ON decreased by 50% for each year of added patient age, when adjusted for sex, ON location, and symptoms. Hip ON showed less spontaneous improvement compared with other joints, and the risk for surgery was 13-fold in hip ON. Grades 3-4 joint ON has the potential to either progress or resolve, warranting follow-up in patients with severe symptoms. Research on secondary prevention should be directed at grade 3-4 joint ON. Osteonecrosis (ON) is a recognised complication of glucocorticoid-based treatment for Hodgkin lymphoma (HL). In a Nordic cohort of 489 paediatric HL patients, a magnetic resonance imaging follow-up study using the Niinim & auml;ki radiological classification system was carried out. Forty-six patients had been diagnosed with ON. A total of 202 ON were identified, of which 77 were joint lesions. Follow-up images were available for 146/202 lesions, with a mean follow-up time of 28 months. During follow-up, 3% of the lesions progressed to joint collapse, whilst 26% improved or resolved. A higher ON grade at diagnosis was associated with a lower likelihood for spontaneous resolution, as was higher patient age. Hip ON showed less spontaneous improvement compared with other joints, and the risk for surgery was 13-fold in hip ON.image

  • 50.
    Aaro, Gustav
    Linköping University, Department of Computer and Information Science.
    Smartphone Based Indoor Positioning Using Wi-Fi Round Trip Time and IMU Sensors2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    While GPS long has been an industry standard for localization of an entity or person anywhere in the world, it loses much of its accuracy and value when used indoors. To enable services such as indoor navigation, other methods must be used. A new standard of the Wi-Fi protocol, IEEE 802.11mc (Wi-Fi RTT), enables distance estimation between the transmitter and the receiver based on the Round-Trip Time (RTT) delay of the signal. Using these distance estimations and the known locations of the transmitting Access Points (APs), an estimation of the receiver’s location can be determined. In this thesis, a smartphone Wi-Fi RTT based Indoor Positioning System (IPS) is presented using an Unscented Kalman Filter (UKF). The UKF using only RTT based distance estimations as input, is established as a baseline implementation. Two extensions are then presented to improve the positioning performance; 1) a dead reckoning algorithm using smartphone sensors part of the Inertial Measurement Unit (IMU) as an additional input to the UKF, and 2) a method to detect and adjust distance measurements that have been made in Non-Line-of-Sight (NLoS) conditions. The implemented IPS is evaluated in an office environment in both favorable situations (plenty of Line-of-Sight conditions) and sub-optimal situations (dominant NLoS conditions). Using both extensions, meter level accuracy is achieved in both cases as well as a 90th percentile error of less than 2 meters.

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