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  • 1.
    Nilsson, Line
    et al.
    Aarhus University, Denmark.
    Palm, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Uppsala University, Sweden.
    Norregaard, Rikke
    Aarhus University, Denmark.
    15-Deoxy-Delta(12,14)-prostaglandin J(2) Exerts Antioxidant Effects While Exacerbating Inflammation in Mice Subjected to Ureteral Obstruction2017In: Mediators of Inflammation, ISSN 0962-9351, E-ISSN 1466-1861, 3924912Article in journal (Refereed)
    Abstract [en]

    Urinary obstruction is associated with inflammation and oxidative stress, leading to renal dysfunction. Previous studies have shown that 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) has both antioxidant and anti-inflammatory effects. Using a unilateral ureteral obstruction (UUO) mouse model, we examined the effects of 15d-PGJ(2) on oxidative stress and inflammation in the kidney. Mice were subjected to UUO for 3 days and treated with 15d-PGJ(2). Protein and RNA expression were examined using immunoblotting and qPCR. 15d-PGJ(2) increased NF-E2-related nuclear factor erythroid-2 (Nrf2) protein expression in response to UUO, and heme oxygenase 1 (HO-1), a downstream target of Nrf2, was induced by 15d-PGJ(2). Additionally, 15d-PGJ(2) prevented protein carbonylation, a UUO-induced oxidative stress marker. Inflammation, measured by nuclear NF-kappa B, F4/80, and MCP-1, was increased in response to UUO and further increased by 15d-PGJ(2). Renal injury was aggravated by 15d-PGJ(2) treatment as measured by kidney injury molecule-1 (KIM-1) and cortical caspase 3 content. No effect of 15d-PGJ(2) was observed on renal function in mice subjected to UUO. This study illustrates differentiated functioning of 15d-PGJ(2) on inflammation and oxidative stress in response to obstructive nephropathy. High concentrations of 15d-PGJ(2) protects against oxidative stress during 3-day UUO in mice; however, it aggravates the associated inflammation.

  • 2.
    Auer, Cornelia
    et al.
    Zuse Institute Berlin, Berlin, Germany.
    Nair, Jaya
    IIIT – Bangalore, Electronics City, Hosur Road, Bangalore, India.
    Zobel, Valentin
    Zuse Institue Berlin, Berlin, Germany.
    Hotz, Ingrid
    Zuse Institue Berlin, Berlin, Germany.
    2D Tensor Field Segmentation2011In: Dagstuhl Follow-Ups, E-ISSN 1868-8977, Vol. 2, 17-35 p.Article in journal (Refereed)
    Abstract [en]

    We present a topology-based segmentation as means for visualizing 2D symmetric tensor fields. The segmentation uses directional as well as eigenvalue characteristics of the underlying field to delineate cells of similar (or dissimilar) behavior in the tensor field. A special feature of the resulting cells is that their shape expresses the tensor behavior inside the cells and thus also can be considered as a kind of glyph representation. This allows a qualitative comprehension of important structures of the field. The resulting higher-level abstraction of the field provides valuable analysis. The extraction of the integral topological skeleton using both major and minor eigenvector fields serves as a structural pre-segmentation and renders all directional structures in the field. The resulting curvilinear cells are bounded by tensorlines and already delineate regions of equivalent eigenvector behavior. This pre-segmentation is further adaptively refined to achieve a segmentation reflecting regions of similar eigenvalue and eigenvector characteristics. Cell refinement involves both subdivision and merging of cells achieving a predetermined resolution, accuracy and uniformity of the segmentation. The buildingblocks of the approach can be intuitively customized to meet the demands or different applications. Application to tensor fields from numerical stress simulations demonstrates the effectiveness of our method.

  • 3.
    Gehlert, Donald R.
    et al.
    Eli Lilly and Company, Indianapolis, IN, USA.
    Cippitelli, Andrea
    National Institute on Alcohol Abuse and Alcoholism, NIH; Bethesda, MD, USA.
    Thorsell, Annika
    National Institute on Alcohol Abuse and Alcoholism, NIH; Bethesda, MD, USA.
    Lê, Anh Dzung
    University of Toronto, Canada.
    Hipskind, Philip A
    Eli Lilly and Company, Indianapolis, IN, USA.
    Hamdouchi, Chafiq
    Eli Lilly and Company, Indianapolis, IN, USA.
    Lu, Jianliang
    Eli Lilly and Company, Indianapolis, IN, USA.
    Hembre, Erik J.
    Eli Lilly and Company, Indianapolis, IN, USA.
    Cramer, Jeffrey
    Eli Lilly and Company, Indianapolis, IN, USA.
    Song, Min
    Eli Lilly and Company, Indianapolis, IN, USA.
    McKinzie, David
    Eli Lilly and Company, Indianapolis, IN, USA.
    Morin, Michelle
    Eli Lilly and Company, Indianapolis, IN, USA.
    Ciccocioppo, Roberto
    University of Camerino, Italy.
    Heilig, Markus
    National Institute on Alcohol Abuse and Alcoholism, NIH; Bethesda, MD, USA.
    3-(4-Chloro-2-morpholin-4-yl-thiazol-5-yl)-8-(1-ethylpropyl)-2,6-dimethyl-imidazo[1,2-b]pyridazine: a novel brain-penetrant, orally available corticotropin-releasing factor receptor 1 antagonist with efficacy in animal models of alcoholism2007In: Journal of Neuroscience, ISSN 0270-6474, E-ISSN 1529-2401, Vol. 27, no 10, 2718-2726 p.Article in journal (Refereed)
    Abstract [en]

    We describe a novel corticotropin-releasing factor receptor 1 (CRF1) antagonist with advantageous properties for clinical development, and its in vivo activity in preclinical alcoholism models. 3-(4-Chloro-2-morpholin-4-yl-thiazol-5-yl)-8-(1-ethylpropyl)-2,6-dimethyl-imidazo[1,2-b]pyridazine (MTIP) inhibited 125I-sauvagine binding to rat pituitary membranes and cloned human CRF1 with subnanomolar affinities, with no detectable activity at the CRF2 receptor or other common drug targets. After oral administration to rats, MTIP inhibited 125I-sauvagine binding to rat cerebellar membranes ex vivo with an ED50 of approximately 1.3 mg/kg and an oral bioavailability of 91.1%. Compared with R121919 (2,5-dimethyl-3-(6-dimethyl-4-methylpyridin-3-yl)-7-dipropylamino-pyrazolo[1,5-a]pyrimidine) and CP154526 (N-butyl-N-ethyl-4,9-dimethyl-7-(2,4,6-trimethylphenyl)-3,5,7-triazabicyclo[4.3.0]nona-2,4,8,10-tetraen-2-amine), MTIP had a markedly reduced volume of distribution and clearance. Neither open-field activity nor baseline exploration of an elevated plus-maze was affected by MTIP (1-10 mg/kg). In contrast, MTIP dose-dependently reversed anxiogenic effects of withdrawal from a 3 g/kg alcohol dose. Similarly, MTIP blocked excessive alcohol self-administration in Wistar rats with a history of dependence, and in a genetic model of high alcohol preference, the msP rat, at doses that had no effect in nondependent Wistar rats. Also, MTIP blocked reinstatement of stress-induced alcohol seeking both in postdependent and in genetically selected msP animals, again at doses that were ineffective in nondependent Wistar rats. Based on these findings, MTIP is a promising candidate for treatment of alcohol dependence.

  • 4.
    Yu, Zhengquan
    et al.
    Linköping University, Department of Neuroscience and Locomotion, Pathology. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Li, Wei
    Linköping University, Department of Neuroscience and Locomotion, Pathology. Linköping University, Faculty of Health Sciences.
    Brunk, Ulf
    Linköping University, Department of Neuroscience and Locomotion, Pathology. Linköping University, Faculty of Health Sciences.
    3-Aminopropanal is a lysosomotropic aldehyde that causes oxidative stress and apoptosis by rupturing lysosomes2003In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 111, no 6, 643-652 p.Article in journal (Refereed)
    Abstract [en]

    During cerebral ischemia and following trauma, potent cytotoxic polyamine-derived aminoaldehydes form, diffuse, and damage adjacent tissues not directly subjected to the initial insult. One such aldehyde is 3-aminopropanal (3-AP). The mechanisms by which such a small aldehydic compound is excessively cytotoxic have been unclear until recently when we showed that 3-AP, having the structure of a weak lysosomotropic base, concentrates within the acidic vacuolar compartment and causes lysosomal rupture that, in turn, induces caspase activation and apoptotic cell death. Here, using cultured J774 cells and 3-AP as a way to selectively burst lysosomes, we show that moderate lysosomal rupture induces a transient wave of oxidative stress. The start of this oxidative stress period is concomitant with a short period of enhanced mitochondrial membrane potential that later fades and is replaced by a decreased potential before the oxidative stress diminishes. The result of the study suggests that oxidative stress, which has often been described during apoptosis induced by agonists other than oxidative stress per se, may be a consequence of lysosomal rupture with direct and/or indirect effects on mitochondrial respiration and electron transport causing a period of passing enhanced formation of reactive oxygen species.

  • 5.
    Saarimäki, Jonas
    et al.
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    Lundberg, Mattias
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    Moverare, Johan
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    Brodin, Håkan
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Science & Engineering. Siemens Industrial Turbomachinery AB, Finspång.
    3D Residual Stresses in Selective Laser Melted Hastelloy X2017In: Residual Stresses 2016: ICRS-10, Materials Research Proceedings 2 (2016), 2017, Vol. 2, 73-78 p.Conference paper (Refereed)
    Abstract [en]

    3D residual stresses in as manufactured EOS NickelAlloy HX, produced by laser powder bed additive manufacturing, are analysed on the surface closest to the build-plate. Due to the severe thermal gradient produced during the melting and solidification process, profound amounts of thermal strains are generated. Which can result in unwanted geometrical distortion and effect the mechanical properties of the manufactured component. Measurements were performed using a four-circle goniometer Seifert X-ray machine, equipped with a linear sensitive detector and a Cr-tube. Evaluation of the residual stresses was conducted using sin2ψ method of the Ni {220} diffraction peak, together with material removal technique to obtain in-depth profiles. An analysis of the material is reported. The analysis reveals unwanted residual stresses, and a complicated non-uniform grain structure containing large grains with multiple low angle grain boundaries together with nano-sized grains. Grains are to a large extent, not equiaxed, but rather elongated.

  • 6.
    Dyverfeldt, Petter
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Bissell, Malenka
    University of Oxford, England.
    Barker, Alex J.
    Northwestern University, IL 60611 USA.
    Bolger, Ann F
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. University of Calif San Francisco, CA USA.
    Carlhäll, Carljohan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Francios, Christopher J.
    University of Wisconsin, WI 53706 USA.
    Frydrychowicz, Alex
    University Hospital Schleswig Holstein, Germany.
    Geiger, Julia
    University of Childrens Hospital Zurich, Switzerland.
    Giese, Daniel
    University Hospital Cologne, Germany.
    Hope, Michael D.
    University of Calif San Francisco, CA USA.
    Kilner, Philip J.
    University of London Imperial Coll Science Technology and Med, England.
    Kozerke, Sebastian
    University of Zurich, Switzerland; ETH, Switzerland.
    Myerson, Saul
    University of Oxford, England.
    Neubauer, Stefan
    University of Oxford, England.
    Wieben, Oliver
    University of Wisconsin, WI 53706 USA.
    Markl, Michael
    Northwestern University, IL 60611 USA; Northwestern University, IL 60611 USA.
    4D flow cardiovascular magnetic resonance consensus statement2015In: Journal of Cardiovascular Magnetic Resonance, ISSN 1097-6647, E-ISSN 1532-429X, Vol. 17, no 72Article, review/survey (Refereed)
    Abstract [en]

    Pulsatile blood flow through the cavities of the heart and great vessels is time-varying and multidirectional. Access to all regions, phases and directions of cardiovascular flows has formerly been limited. Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) has enabled more comprehensive access to such flows, with typical spatial resolution of 1.5x1.5x1.5 - 3x3x3 mm(3), typical temporal resolution of 30-40 ms, and acquisition times in the order of 5 to 25 min. This consensus paper is the work of physicists, physicians and biomedical engineers, active in the development and implementation of 4D Flow CMR, who have repeatedly met to share experience and ideas. The paper aims to assist understanding of acquisition and analysis methods, and their potential clinical applications with a focus on the heart and greater vessels. We describe that 4D Flow CMR can be clinically advantageous because placement of a single acquisition volume is straightforward and enables flow through any plane across it to be calculated retrospectively and with good accuracy. We also specify research and development goals that have yet to be satisfactorily achieved. Derived flow parameters, generally needing further development or validation for clinical use, include measurements of wall shear stress, pressure difference, turbulent kinetic energy, and intracardiac flow components. The dependence of measurement accuracy on acquisition parameters is considered, as are the uses of different visualization strategies for appropriate representation of time-varying multidirectional flow fields. Finally, we offer suggestions for more consistent, user-friendly implementation of 4D Flow CMR acquisition and data handling with a view to multicenter studies and more widespread adoption of the approach in routine clinical investigations.

  • 7.
    Li, Wei
    et al.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Johnson, Henrik
    Linköping University, Department of Clinical and Experimental Medicine, Experimental Pathology. Linköping University, Faculty of Health Sciences.
    Yuan, Xi-Ming
    Linköping University, Department of Clinical and Experimental Medicine, Experimental Pathology. Linköping University, Faculty of Health Sciences.
    Jonasson, Lena
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    7beta-hydroxycholesterol induces natural killer cell death via oxidative lysosomal destabilization2009In: Free radical research, ISSN 1071-5762, E-ISSN 1029-2470, Vol. 43, no 11, 1072-1079 p.Article in journal (Refereed)
    Abstract [en]

    Peripheral natural killer (NK) cells are reduced in patients with coronary artery disease and highly susceptible to apoptosis induced by oxidized lipids including 7beta-hydroxycholesterol (7betaOH) in vitro. The present study aimed to further explore the mechanisms behind 7betaOH-mediated cytotoxicity to human NK cells. Human NK cells were purified and treated with 7betaOH in different concentrations and times. Cell death, lysosomal and mitochondrial permeabilization and reactive oxygen species (ROS) production were then analysed. The 7betaOH induced time and dose dependent apoptosis and necrosis in human NK cells, which was preceded by loss of lysosomal integrity and enhanced ROS production. At later time points, the mitochondrial membrane permeability in 7betaOH-treated cells was significantly increased. The findings indicate that 7betaOH induces human NK cell death through early lysosomal permeabilization and consequent oxidative stress. The data further suggest that 7betaOH may induce immune disturbances in clinical settings such as atherosclerosis.

  • 8.
    Li, Wei
    et al.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Johnson, Henrik
    Linköping University, Department of Clinical and Experimental Medicine, Experimental Pathology. Linköping University, Faculty of Health Sciences.
    Yuan, Xi-Ming
    Linköping University, Department of Clinical and Experimental Medicine, Experimental Pathology. Linköping University, Faculty of Health Sciences.
    Jonasson, Lena
    Linköping University, Department of Medical and Health Sciences, Internal Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    7ß-hydroxycholesterol induces natural killer cell death via oxidative lysosomal destabilization2009In: Free radical research, ISSN 1071-5762, E-ISSN 1029-2470, Vol. 43, no 11, 1072-1079 p.Article in journal (Refereed)
    Abstract [en]

    Peripheral natural killer (NK) cells are reduced in patients with coronary artery disease and highly susceptible to apoptosis induced by oxidized lipids including 7beta-hydroxycholesterol (7betaOH) in vitro. The present study aimed to further explore the mechanisms behind 7betaOH-mediated cytotoxicity to human NK cells. Human NK cells were purified and treated with 7betaOH in different concentrations and times. Cell death, lysosomal and mitochondrial permeabilization and reactive oxygen species (ROS) production were then analysed. The 7betaOH induced time and dose dependent apoptosis and necrosis in human NK cells, which was preceded by loss of lysosomal integrity and enhanced ROS production. At later time points, the mitochondrial membrane permeability in 7betaOH-treated cells was significantly increased. The findings indicate that 7betaOH induces human NK cell death through early lysosomal permeabilization and consequent oxidative stress. The data further suggest that 7betaOH may induce immune disturbances in clinical settings such as atherosclerosis.

  • 9.
    Fritzin, Jonas
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Svensson, Christer
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A +32dBm 1.85GHz Class-D Outphasing RF PA in 130nm CMOS for WCDMA/LTE2011In: Proceedings of the IEEE European Solid-State Circuits Conference (ESSCIRC), IEEE , 2011, 127-130 p.Conference paper (Refereed)
    Abstract [en]

    This paper presents a Class-D outphasing RF Power Amplifier (PA) which can operate at a 5.5V supply and deliver +32dBm at 1.85 GHz in a standard 130nm CMOS technology. The PA utilizes four on-chip transformers to combine the outputs of eight Class-D stages. The Class-D stages utilize a cascode configuration, driven by an AC-coupled low-voltage driver, to allow a 5.5 V supply in the 1.2/2.5 V 130nm process without excessive device voltage stress. Spectral and modulation requirements were met when a WCDMA and an LTE signal (20 MHz, 16-QAM) were applied to the outphasing PA. At +28.0 dBm channel power for the WCDMA signal, the measured ACLR at 5 MHz and 10 MHz offset were −38.7 dBc and −47.0 dBc, respectively. At +24.9 dBm channel power for the LTE signal, the measured ACLR at 20MHz offset was −34.9 dBc. To the authors' best knowledge, the PA presented in this work has a 3.9 dB higher output power compared to published CMOS Class-D RF PAs.

  • 10.
    Jayachandra Pandiyan, Muneeswaran
    Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics.
    A bioinformatics approach to investigate the function of non specific lipid transfer proteins in Arabidopsis thaliana2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Plant non specific lipid transfer proteins (nsLTPs) enhance in vitro transfer of phospholipids between membranes. Our analysis exploited the large amount of Arabidopsis transcriptome data in public databases to learn more about the function of nsLTPs. The analysis revealed that some nsLTPs are expressed only in roots, some are seed specific, and others are specific for tissues above ground whereas certain nsLTPs show a more general expression pattern. Only few nsLTPs showed a strong up or downregulation after that the Arabidopsis plant had suffered from biotic or abiotic stresses. However, salt, high osmosis and UV-B radiation caused upregulation of some nsLTP genes. Further, when the coexpression pattern of the A.thaliana nsLTPs were investigated, we found that there were several modules of nsLTP genes that showed strong coexpression indicating an involvement in related biological processes. Our finding reveals that the nsLTPs gene was significantly correlated with lipase and peroxidase activity. Hence we concluded that the nsLTPs may play a role in seed germination, signalling and ligning biosynthesis.

  • 11.
    Agnafors, Sara
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Västra Götalandsregionen, Södra Älvsborgs Sjukhus, Barn- och ungdomspsykiatriska kliniken.
    A Biopsychosocial and Long Term Perspective on Child Behavioral Problems: Impact of Risk and Resilience2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mental health has become a prominent issue in society. Yet, much remains unknown about the etiology of psychiatric disorders. The aim of the present thesis was to investigate the association between biological, psychological and social factors of risk and resilience and behavioral problems in a birth cohort of Swedish children. 1723 mothers and their children were followed from birth to the age of 12 as part of the South East Sweden Birth Cohort Study (the SESBiC study). Information was gathered through register data, standardized questionnaires and DNA samples.

    In study I, stability of maternal symptoms of depression and the impact on child behavior at age 12 were investigated. The prevalence of depressive symptoms was found to be 12.0 % postpartum. Symptoms of postpartum depression significantly increased the risk for subsequent depressive symptoms 12 years later in women. Children whose mothers reported concurrent symptoms of depression and anxiety had an increased risk for both internalizing and externalizing problems at age 12, but no long term effect on child behavior was seen for postpartum depressive symptoms. The greatest risk was seen for children whose mothers reported symptoms of depression on both occasions. In study II, the impact of gene-environment interaction of 5-HTTLPR and BDNF Val66Met and experience of life events together with symptoms of maternal depression and anxiety on child behavior at age 12 was studied. A main effect of 5-HTTLPR was noticed, but no geneenvironment effects were shown. Similarly to study I, concurrent symptoms of maternal depression and anxiety were an important predictor of child behavioral problems. A high degree of psychosocial stress around childbirth was found to have long lasting detrimental effects on child behavior, increasing the risk for internalizing problems at age 12. Study III investigated the impact of geneenvironment interactions of 5-HTTLPR and BDNF Val66Met and life events together with symptoms of maternal depression and birth characteristics on behavioral problems at age 3. Symptoms of postpartum depression were found to predict internalizing as well as externalizing problems in children three years later. Child experience of life events was a stable predictor of behavioral problems across the scales similar to sociodemographic factors such as parental immigration status and unemployment. No gene-environment interaction effects of 5-HTTLPR or BDNF Val66Met were shown. Study IV used the risk factors identified in studies I-III to investigate factors of resilience to behavioral problems at age 12. The l/l genotype of 5-HTTLPR was associated with a lower risk for behavioral problems at age 12, especially for children facing low adversity. Good social functioning was found to be a general resource factor, independent of the level of risk, while an easy temperament was associated with resilience for children with a high degree of adversity. However, effect sizes were small.

    In summary, the results from the present thesis emphasize the importance of maternal mental health and sociodemographic factors for child mental health at ages 3 and 12, which must be taken into account in clinical settings. Moreover, it adds to the null-findings of the gene-environment effect of 5-HTTLPR and BDNF Val66Met on behavioral problems in children, but indicates a main effect of 5-HTTLPR on internalizing symptoms at age 12.

    List of papers
    1. Symptoms of Depression Postpartum and 12 years Later-Associations to Child Mental Health at 12 years of Age
    Open this publication in new window or tab >>Symptoms of Depression Postpartum and 12 years Later-Associations to Child Mental Health at 12 years of Age
    2013 (English)In: Maternal and Child Health Journal, ISSN 1092-7875, E-ISSN 1573-6628, Vol. 17, no 3, 405-414 p.Article in journal (Refereed) Published
    Abstract [en]

    Children of depressed mothers have been shown to express behaviour problems to a greater extent than children of non-depressed mothers. The purpose of this study was to examine the persistence of depressive symptoms in mothers and to evaluate the relative importance of symptoms of postpartum depression (PPD) and concurrent maternal symptoms of depression, on child behaviour at age 12. A birth cohort of 1,707 children and their mothers was followed from 3 months after birth to 12 years after birth. Self-reported symptoms of depression in mothers were assessed at baseline and 12-year follow-up where 893 mothers (52.3 %) and their children participated. The mothers reports on the behaviour of their children at age 12 were used. Multivariate analysis was used to assess factors that increased the risk of child behaviour problems. At baseline, 10.4 % scored above the cutoff for symptoms of postpartum depression. At follow up, 18.2 % scored above the cutoff for depressive symptoms. Multivariate analysis showed that ongoing maternal symptoms of depression, as distinct from PPD-symptoms, was the strongest predictor of child behaviour problems at age 12. The gender of the child and socio-demographic factors at baseline were additional factors that affected the risk of behaviour problems in the 12 year old children. Children of mothers who reported symptoms of depression, both postpartum and at follow-up, were at a greater risk of behaviour problems compared to children of women with no depressive symptoms on either occasion. Our findings indicate that recurrent and ongoing maternal depressive symptoms significantly increase the risk of child behaviour problems as reported by mothers, while symptoms of PPD do not seem to result in an increased risk of behaviour problems in 12 year olds. High maternal socio-demographic life stress at childbirth constitutes an important risk factor for later child behaviour problems.

    Place, publisher, year, edition, pages
    Springer Verlag (Germany), 2013
    Keyword
    CBCL, Children, Mental health, Postpartum depression, SESBiC-study
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-90750 (URN)10.1007/s10995-012-0985-z (DOI)000316021200003 ()
    Available from: 2013-04-05 Created: 2013-04-05 Last updated: 2017-12-06
    2. Effect of gene, environment and maternal depressive symptoms on pre-adolescence behavior problems - a longitudinal study.
    Open this publication in new window or tab >>Effect of gene, environment and maternal depressive symptoms on pre-adolescence behavior problems - a longitudinal study.
    Show others...
    2013 (English)In: Child and Adolescent Psychiatry and Mental Health, ISSN 1753-2000, E-ISSN 1753-2000, Vol. 7, no 1, 10- p.Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: Depression is a common and disabling condition with a high relapse frequency. Maternal mental health problems and experience of traumatic life events are known to increase the risk of behavior problems in children. Recently, genetic factors, in particular gene-by-environment interaction models, have been implicated to explain depressive etiology. However, results are inconclusive.

    METHODS: Study participants were members of the SESBiC-study. A total of 889 mothers and their children were followed during the child's age of 3 months to 12 years. Information on maternal depressive symptoms was gathered postpartum and at a 12 year follow-up. Mothers reported on child behavior and traumatic life events experienced by the child at age 12. Saliva samples were obtained from children for analysis of 5-HTTLPR and BDNF Val66Met polymorphisms.

    RESULTS: Multivariate analysis showed a significant association between maternal symptoms of depression and anxiety, and internalizing problems in 12-year-old children (OR 5.72, 95% CI 3.30-9.91). Furthermore, carriers of two short alleles (s/s) of the 5-HTTLPR showed a more than 4-fold increased risk of internalizing problems at age 12 compared to l/l carriers (OR 4.73, 95% CI 2.14-10.48). No gene-by-environment interaction was found and neither depressive symptoms postpartum or traumatic experiences during childhood stayed significant in the final model.

    CONCLUSIONS: Concurrent maternal symptoms of depression and anxiety are significant risk factors for behavior problems in children, which need to be taken into account in clinical practice. Furthermore, we found a main effect of 5-HTTLPR on internalizing symptoms in 12-year-old children, a finding that needs to be confirmed in future studies.

    Place, publisher, year, edition, pages
    BioMed Central, 2013
    National Category
    Psychiatry
    Identifiers
    urn:nbn:se:liu:diva-104869 (URN)10.1186/1753-2000-7-10 (DOI)23518193 (PubMedID)
    Available from: 2014-02-28 Created: 2014-02-28 Last updated: 2017-12-05Bibliographically approved
    3. Early predictors of behavioural problems in pre-schoolers: a longitudinal study of constitutional and environmental main and interaction effects
    Open this publication in new window or tab >>Early predictors of behavioural problems in pre-schoolers: a longitudinal study of constitutional and environmental main and interaction effects
    Show others...
    2016 (English)In: BMC Pediatrics, ISSN 1471-2431, E-ISSN 1471-2431, Vol. 16Article in journal (Refereed) Published
    Abstract [en]

    Background: The early environment is important for child development and wellbeing. Gene-by-environment studies investigating the impact of the serotonin transporter genelinked polymorphic region (5-HTTLPR) and the Brain Derived Neurotrophic Factor (BDNF) Val66Met polymorphisms by life events on mental health and behaviour problems have been inconclusive. Methodological differences regarding sample sizes, study population, definitions of adversities and measures of mental health problems obstacle their comparability. Furthermore, very few studies included children. The aim of this study was to examine the associations between a broad range of risk factors covering pregnancy and birth, genetic polymorphism, experience of multiple life events and psychosocial environment, and child behaviour at age three, using a comparably large, representative, population-based sample.

    Methods: A total of 1,106 children, and their mothers, were followed from pregnancy to age three. Information on pregnancy and birth-related factors was retrieved from the Medical Birth Register. Questionnaires on depressive symptoms, child behaviour and child experiences of life events were filled in by the mothers. Child saliva samples were used for genotyping the 5-HTTLPR and BDNF Val66Met polymorphisms. Multiple logistic regression was used to investigate the association between psychological scales and genetic polymorphisms.

    Results: Symptoms of postpartum depression increased the risk of both internalizing and externalizing problems. Experience of multiple life events was also a predictor of behavioural problems across the scales. No gene-by-environment or gene-bygene-by-environment interactions were found. Children of immigrants had an increased risk of internalizing problems and parental unemployment was significantly associated with both internalizing and externalizing type of problems.

    Conclusion: This study shows the importance of the psychosocial environment for psychosocial health in preschool children, and adds to  the literature of null-findings of gene-by-environment effects of 5-HTTLPR and BDNF in children

    National Category
    Psychiatry
    Identifiers
    urn:nbn:se:liu:diva-124207 (URN)10.1186/s12887-016-0614-x (DOI)000377535800002 ()
    Note

    Funding agencies:Funding was obtained from the Swedish Council for Working Life and Social Research (FAS), the Swedish Research Council (VR), the Clas Groschinsky Memorial Foundation, Stockholm, Samariten Foundation, Stockholm, the Hallsten Research Foundation and ALF, County Council of Ostergotland.

    Vid tiden för publicering förelåg publikationen endast som manuskript

    Available from: 2016-01-22 Created: 2016-01-22 Last updated: 2017-11-30Bibliographically approved
    4. A biopsychosocial approach to risk and resilience on behavior in children followed from birth to age twelve
    Open this publication in new window or tab >>A biopsychosocial approach to risk and resilience on behavior in children followed from birth to age twelve
    Show others...
    2016 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    An increasing prevalence of mental health problems calls for more knowledge into factors associated with resilience in the context of child behavior. Biological factors are seldom considered in psychosocial models of resilience. The present study used multiple statistical methodologies to examine a biopsychosocial model of risk and resilience on behavior at preadolescence. Data from 889 children and their mothers were used. A cumulative adversity score was created by combining maternal symptoms of depression, psychosocial risk and children’s experiences of life events. The proposed resilience factors investigated were candidate genetic polymorphisms, child temperament and social functioning, and maternal sense of coherence. Results show that the l/l genotype of the serotonin transporter linked polymorphic region (5-HTTLPR) was associated with lower internalizing scores, especially for children exposed to low adversity. An easy temperament was associated with resilient outcomes for children exposed to high adversity. Child social functioning was found to be more of a general resource variable buffering risk in both high and low adversity groups. The results support a multiple level model of resilience indicating effects, though small, of both biological and psychosocial factors. The present findings call for both preventive actions and further studies on biopsychosocial models in resilience research.

    Keyword
    Child, genotype, longitudinal, mental health, resilience
    National Category
    Psychiatry
    Identifiers
    urn:nbn:se:liu:diva-124208 (URN)
    Available from: 2016-01-22 Created: 2016-01-22 Last updated: 2016-01-22Bibliographically approved
  • 12.
    Filla, Reno
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Olsson, Erik M. G.
    Dept. of Public Health and caring Sciences, Uppsala University, Sweden.
    Schéele, Bo H. C. von
    Stress Medicien AB, Bergvik, Sweden.
    Ohlsson, Kjell
    Linköping University, Department of Management and Engineering, Industrial ergonomics. Linköping University, The Institute of Technology.
    A Case Study on Quantifying the Workload of Working Machine Operators by Means of Psychophysiological MeasurementsManuscript (preprint) (Other academic)
    Abstract [en]

    In this study of eighteen wheel loader operators, test-driving a machine in three different traction force settings, we examine if a workload index derived from psychophysiological measurements of heart rate, finger temperature, skin conductance, respiration rate and end-tidal CO2-concentration in exhaled air can be used to assess operator workload in sufficient detail to use it as a complement to traditional subjective evaluations, and also to use such measurements in a workload-adaptive operator assistance system in a longer perspective.

  • 13.
    Bäckman, Carl G
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Orwelius, Lotti
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Sjöberg, Folke
    Linköping University, Department of Clinical and Experimental Medicine, Burn Unit . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Plastic Surgery, Hand surgery UHL.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Walther, Sten M
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    A case-control study of the influence of the ICU-diary concept on mastery and hopelessness six months after critical illnessManuscript (preprint) (Other academic)
    Abstract [en]

    The ICU-diary concept is associated with less post-traumatic stress syndrome and improved perceived health-related quality-of-life (HRQoL) after critical illness, but little is known about its effect on the coping- mastery process, or whether it reduces hopelessness.

    Objective: To see if the ICU-diary concept improves the patient’s ability to master his/her situation after critical illness, and if it reduces the feeling of hopelessness.

    Design: Case control study (subgroup analysis of a multi-centre study on health-related quality-of-life (HRQoL).

    Setting: Non-academic 8-bed general ICU.

    Patients: Adults admitted between March 2002 and June 2004.

    Measurements: Mastery and hopelessness were determined using validated questionnaires (the Mastery-Coping scale and a consolidated 2–item hopelessness questionnaire) which were sent home to patients 6 months after critical illness. Responses were compared between patients that received (Cases: n=38) or did not receive an ICU-diary (Controls: n=76) . Diaries were used when a long and complicated stay on the ICU was expected. Controls were matched with diary patients by gender and age. The effect of the ICU-diary was also examined using a multiple regression model.

    Results: The ICU-diary concept group scored significantly higher than the No-diary group in mastery (22.1 vs. 20.4, P<0.05) and lower in hopelessness scores (1.3 vs. 1.6, P<0.05). The positive influence of the ICU-diary disappeared after adjustment for confounding factors in a multiple regression model.

    Conclusion: We were unable to verify any positive influence of the ICU-diary concept on mastery and hopelessness 6 months after critical illness.

  • 14. Haussühl, Kirsten
    et al.
    Andersson, Bertil
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Cell biology.
    Adamska, Iwona
    A chloroplast DegP2 protease performs the primary cleavage of the photodamaged D1 protein in plant photosystem II2001In: EMBO Journal, ISSN 0261-4189, E-ISSN 1460-2075, Vol. 20, no 4, 713-722 p.Article in journal (Refereed)
    Abstract [en]

    Although light is the ultimate substrate in photosynthesis, it can also be harmful and lead to oxidative damage of the photosynthetic apparatus. The main target for light stress is the central oxygen-evolving photosystem II (PSII) and its D1 reaction centre protein. Degradation of the damaged D1 protein and its rapid replacement by a de novo synthesized copy represent the important repair mechanism of PSII crucial for plant survival under light stress conditions. Here we report the isolation of a single-copy nuclear gene from Arabidopsis thaliana, encoding a protease that performs GTP-dependent primary cleavage of the photodamaged D1 protein and hence catalysing the key step in the repair cycle in plants. This protease, designated DegP2, is a homologue of the prokaryotic Deg/Htr family of serine endopeptidases and is associated with the stromal side of the non-appressed region of the thylakoid membranes. Increased expression of DegP2 under high salt, desiccation and light stress conditions was measured at the protein level.

  • 15.
    Schmidt, Susann
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Czigany, Zsolt
    Hungarian Academic Science, Hungary.
    Wissting, Jonas
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Janzén, Erik
    Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, Faculty of Science & Engineering.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Ivanov, Ivan Gueorguiev
    Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, Faculty of Science & Engineering.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    A comparative study of direct current magnetron sputtering and high power impulse magnetron sputtering processes for CNX thin film growth with different inert gases2016In: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 64, 13-26 p.Article in journal (Refereed)
    Abstract [en]

    Reactive direct current magnetron sputtering (DCMS) and high power impulse magnetron sputtering (HiPIMS) discharges of carbon in different inert gas mixtures (N-2/Ne, N-2/Ar, and N-2/Kr) were investigated for the growth of carbon-nitride (CNX) thin films. Ion mass spectrometry showed that energies of abundant plasma cations are governed by the inert gas and the N-2-to-inert gas flow ratios. The population of ion species depends on the sputter mode; HiPIMS yields approximately ten times higher flux ratios of ions originating from the target to process gas ions than DCMS. Exceptional are discharges in Ne with N-2-to-Ne flow ratios &lt;20%. Here, cation energies and the amount of target ions are highest without influence on the sputter mode. CNX thin films were deposited in 14% N-2/inert gas mixtures at substrate temperatures of 110 degrees C and 430 degrees C. The film properties show a correlation to the substrate temperature, the applied inert gas and sputter mode. The mechanical performance of the films is mainly governed by their morphology and composition, but not by their microstructure. Amorphous and fullerene-like CN0.14 films exhibiting a hardness of similar to 15 GPa and an elastic recovery of similar to 90% were deposited at 110 degrees C in reactive Kr atmosphere by DCMS and HiPIMS.

  • 16.
    Zetterqvist, Maria
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Child and Adolescent Psychiatry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Child and Adolescent Psychiatry in Linköping.
    Lundh, Lars-Gunnar
    Lund University, Sweden .
    Svedin, Carl Göran
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    A Comparison of Adolescents Engaging in Self-Injurious Behaviors With and Without Suicidal Intent: Self-Reported Experiences of Adverse Life Events and Trauma Symptoms2013In: Journal of Youth and Adolescence, ISSN 0047-2891, E-ISSN 1573-6601, Vol. 42, no 8, 1257-1272 p.Article in journal (Refereed)
    Abstract [en]

    Research comparing adolescents engaging in suicidal and non-suicidal self-injury (NSSI), both separately and in combination, is still at an early stage. The purpose of the present study was to examine overlapping and distinguishable features in groups with different types of self-injurious behaviors, using a large community sample of 2,964 (50.6 % female) Swedish adolescents aged 15-17 years. Adolescents were grouped into six categories based on self-reported lifetime prevalence of self-injurious behaviors. Of the total sample, 1,651 (55.7 %) adolescents reported no self-injurious behavior, 630 (21.2 %) reported NSSI 1-4 times, 177 (6.0 %) reported NSSI 5-10 times, 311 (10.5 %) reported NSSI a parts per thousand yen 11 times, 26 (0.9 %) reported lifetime prevalence of suicide attempt and 169 (5.7 %) adolescents reported both NSSI and suicide attempt. After controlling for gender, parental occupation and living conditions, there were significant differences between groups. Pairwise comparisons showed that adolescents with both NSSI and suicide attempt reported significantly more adverse life events and trauma symptoms than adolescents with only NSSI, regardless of NSSI frequency. The largest differences (effect sizes) were found for interpersonal negative events and for symptoms of depression and posttraumatic stress. Adolescents with frequent NSSI reported more adversities and trauma symptoms than those with less frequent NSSI. There were also significant differences between all the NSSI groups and adolescents without any self-injurious behavior. These findings draw attention to the importance of considering the cumulative exposure of different types of adversities and trauma symptoms when describing self-injurious behaviors, with and without suicidal intent.

  • 17.
    Zidar, Josefina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Balogh, Alexandra
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Favati, Anna
    Stockholm University, Sweden.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Leimar, Olof
    Stockholm University, Sweden.
    Lovlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    A comparison of animal personality and coping styles in the red junglefowl2017In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 130, 209-220 p.Article in journal (Refereed)
    Abstract [en]

    There is an increased focus in biology on consistent behavioural variation. Several terms are used to describe this variation, including animal personality and coping style. Both terms describe between individual consistency in behavioural variation; however, they differ in the behavioural assays typically used, the expected distribution of response variables, and whether they incorporate variation in behavioural flexibility. Despite these differences, the terms are often used interchangeably. We conducted experiments using juvenile and adult red junglefowl, Gallus gallus, as subjects to explore the degree to which animal personality and coping styles overlap. We demonstrate that animal personality and coping styles can be described in this species, and that shyer individuals had more flexible responses, as expected for coping styles. Behavioural responses from both personality and coping style assays had continuous distributions, and were not clearly separated into two types. Behavioural traits were not correlated and, hence, there was no evidence of a behavioural syndrome. Further, behavioural responses obtained in personality assays did not correlate with those from coping style tests. Animal personality and coping styles are therefore not synonymous in the red junglefowl. We suggest that the terms animal personality and coping style are not equivalent and should not be used interchangeably. (C) 2017 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

    The full text will be freely available from 2019-07-22 15:41
  • 18.
    McAuliffe, Tomomi
    et al.
    Curtin University, Australia.
    Vaz, Sharmila
    Curtin University, Australia.
    Falkmer, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center. Curtin University, Australia; La Trobe University, Australia; Cooperat Research Centre Living Autism Spectrum Disorder, Australia.
    Cordier, Reinie
    Curtin University, Australia.
    A comparison of families of children with autism spectrum disorders in family daily routines, service usage, and stress levels by regionality2017In: Developmental Neurorehabilitation, ISSN 1751-8423, E-ISSN 1751-8431, Vol. 20, no 8, 483-490 p.Article in journal (Refereed)
    Abstract [en]

    Purpose: To explore whether family routines, service usage, and stress levels in families of children with autism spectrum disorder differ as a function of regionality. Methods: Secondary analysis of data was undertaken from 535 surveys. Univariate and multivariate analyses were performed to investigate differences between families living in densely populated (DP) areas and less densely populated (LDP) areas. Results: Families living in LDP areas were found to: (1) have reduced employment hours (a two-parent household: Exp (B) = 3.48, p amp;lt; .001, a single-parent household: Exp (B) = 3.32, p = .011); (2) travel greater distance to access medical facilities (Exp (B) = 1.27, p = .006); and (3) report less severe stress levels (Exp (B) = 0.22, p = .014). Conclusions: There were no differences in family routines; however, flexible employment opportunities and travel distance to medical services need to be considered in families living in LDP areas.

  • 19.
    Edlund, Ulf
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Mechanics.
    Volgers, Pieter
    A composite ply failure model based on continuum damage mechanics2004In: Composite structures, ISSN 0263-8223, E-ISSN 1879-1085, Vol. 65, no 3-4, 347-355 p.Article in journal (Refereed)
    Abstract [en]

    A material model including the failure behaviour is derived for a thin unidirectional (UD) composite ply. The model is derived within a thermodynamic framework and the failure behaviour is modelled using continuum damage mechanics. The following features describe the model: (i) The ply is assumed to be in a plane state of stress. (ii) Three damage variables associated with the stress in the fibre-, transverse and shear directions, respectively, are used. (iii) The plastic behaviour of the matrix material is modelled. (iv) The difference in the material response in tensile and compressive loading is modelled. (v) Rate dependent behavior of plasticity and damage (i.e. strength) is modelled.

  • 20. Hilding, D.
    et al.
    Torstenfelt, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Solid Mechanics .
    Klarbring, Anders
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Mechanics .
    A computational methodology for shape optimization of structures in frictionless contact2001In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 190, no 31, 4043-4060 p.Article in journal (Refereed)
    Abstract [en]

    This paper presents a computational methodology for shape optimization of structures in frictionless contact, which provides a basis for developing user-friendly and efficient shape optimization software. For evaluation it has been implemented as a subsystem of a general finite element software. The overall design and main principles of operation of this software are outlined. The parts connected to shape optimization are described in more detail. The key building blocks are: analytic sensitivity analysis, an adaptive finite element method, an accurate contact solver, and a sequential convex programing optimization algorithm. Results for three model application examples are presented, in which the contact pressure and the effective stress are optimized. cr 2001 Elsevier Science B.V. All rights reserved.

  • 21.
    Andersson, Per Gösta
    Linköping University, The Institute of Technology. Linköping University, Department of Mathematics, Mathematical Statistics .
    A conditional perspective of weighted variance estimation of the optimal regression estimator2006In: Journal of Statistical Planning and Inference, ISSN 0378-3758, E-ISSN 1873-1171, Vol. 136, no 1, 221-234 p.Article in journal (Refereed)
    Abstract [en]

    The estimation of the variance for the GREG (general regression) estimator by weighted residuals is widely accepted as a method which yields estimators with good conditional properties. Since the optimal (regression) estimator shares the properties of GREG estimators which are used in the construction of weighted variance estimators, we introduce the weighting procedure also for estimating the variance of the optimal estimator. This method of variance estimation was originally presented in a seemingly ad hoc manner, and we shall discuss it from a conditional point of view and also look at an alternative way of utilizing the weights. Examples that stress conditional behaviour of estimators are then given for elementary sampling designs such as simple random sampling, stratified simple random sampling and Poisson sampling, where for the latter design we have conducted a small simulation study. © 2004 Elsevier B.V. All rights reserved.

  • 22.
    Sharifimajd, Babak
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    A Continuum Framework for Modeling the Excitation–Contraction Coupling of Smooth Muscle2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Excitation-contraction coupling of smooth muscle refers to a chain of coupled physiological processes which convert a stimulus to a mechanical response. These processes can be disassociated into ionic transport during cell membrane excitation, activation of myosin light chains, and muscle contraction caused by actin-myosin interaction (filament sliding). This thesis concerns the development of a framework which allows to model the smooth muscle excitation-contraction coupling constitutively by applying the principle of virtual power and dissipation inequality. In doing so, the transport of ions through membrane channels is characterized by an ionic flux and an ionic supply, both governed by an electrochemical potential energy. By letting the Helmholtz free energy to be dependent on the myosin light chain configurations during contraction, the myosin light chain activation process, i.e., myosin phosphorylation, is included. The activation process links the membrane excitation to the filament sliding. A contractile element is presented to replicate the active deformation caused by the filament sliding within the smooth muscle cell. This deformation is coupled to the overall deformation of the muscle tissue by assuming a distinct principal alignment for the contractile elements.

    By employing this framework, an electro-chemo-mechanical model is derived by which the mechanical response of smooth muscle to an electrical stimulus is determined. This model is evaluated by comparing the model response to the experimental isometric stress data obtained from rat uterine smooth muscle tissue. By implementing this model in a finite element program, human uterine contractions during labor are simulated. This simulation determines important clinical factors, e.g., intrauterine pressure and provides the opportunity to investigate the effect of physiological and structural parameters on the uterine contractility.

    Finally, a methodology to accommodate individualized parameters from intrauterine pressure measurements is established. This methodology allows to develop models with potentials of being used clinically to diagnose difficulties during labor and delivery.

    List of papers
    1. A continuum model for skeletal muscle contraction at homogeneous finite deformations
    Open this publication in new window or tab >>A continuum model for skeletal muscle contraction at homogeneous finite deformations
    2013 (English)In: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 12, no 5, 965-973 p.Article in journal (Refereed) Published
    Abstract [en]

    The contractile force in skeletal muscle models is commonly postulated to be the isometric force multiplied by a set of experimentally motivated functions which account for the muscle’s active properties. Although both flexible and simple, this approach does not automatically guarantee a thermodynamically consistent behavior. In contrast, the continuum mechanical model proposed herein is derived from fundamental principles in mechanics and guarantees a dissipative behavior. Further, the contractile force is associated with a friction clutch which provides a simple and well-defined macroscopic model for cycling cross-bridges. To show the performance of the model, it is specialized to standard experiments for rabbit tibialis anterior muscle. The results show that the model is able to capture important characteristics of skeletal muscle.

    Place, publisher, year, edition, pages
    Springer, 2013
    Keyword
    Skeletal muscle, Contractile element, Dissipation inequality, Strain-energy function, Continuum model
    National Category
    Other Mechanical Engineering
    Identifiers
    urn:nbn:se:liu:diva-85805 (URN)10.1007/s10237-012-0456-x (DOI)000324378900008 ()
    Funder
    Swedish Research Council
    Available from: 2012-11-28 Created: 2012-11-28 Last updated: 2018-01-03Bibliographically approved
    2. A continuum model for excitation–contraction of smooth muscle under finite deformations
    Open this publication in new window or tab >>A continuum model for excitation–contraction of smooth muscle under finite deformations
    2014 (English)In: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 355, 1-9 p.Article in journal (Refereed) Published
    Abstract [en]

    The main focus in most of continuum based muscle models is the muscle contraction dynamics while other physiological processes governing muscle contraction, e.g., the cell membrane excitation and the activation, are ignored. These latter processes are essential to initiate contraction and to determine the amount of generated force, and by excluding them, the developed model cannot replicate the true behavior of the muscle in question. The aim of this study is to establish a thermodynamically and physiologically consistent framework which allows to model smooth muscle contraction by including cell membrane excitability and kinetics of myosin phosphorylation, along with dynamics of smooth muscle contraction. The model accounts for these processes through a set of coupled dissipative constitutive equations derived by applying the first principles. To show the performance of the derived model, it is evaluated for two different cases: a mechanochemical study of pig taenia coli cells where the excitation process is excluded, and a complete excitation–contraction process of rat myometrium. The results show that the model is able to replicate important aspects of the smooth muscle EC process acceptably.

    Place, publisher, year, edition, pages
    Elsevier, 2014
    Keyword
    Smooth muscle excitation–contraction, Smooth muscle continuum model, The membrane model, Hodgkin-Huxley model, Hai-Murphy model
    National Category
    Other Mechanical Engineering
    Identifiers
    urn:nbn:se:liu:diva-100778 (URN)10.1016/j.jtbi.2014.03.016 (DOI)000337865100001 ()
    Available from: 2013-11-12 Created: 2013-11-12 Last updated: 2018-01-03Bibliographically approved
    3. Simulating uterine contraction by using an electro-chemo-mechanical model
    Open this publication in new window or tab >>Simulating uterine contraction by using an electro-chemo-mechanical model
    2016 (English)In: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 15, no 3, 497-510 p.Article in journal (Refereed) Published
    Abstract [en]

    Contractions of uterine smooth muscle cells consist of a chain of physiological processes. These contractions provide the required force to expel the fetus from the uterus. The inclusion of these physiological processes is, therefore, imperative when studying uterine contractions. In this study, an electro-chemo-mechanical model to replicate the excitation, activation, and contraction of uterine smooth muscle cells is developed. The presented modeling strategy enables efficient integration of knowledge about physiological processes at the cellular level to the organ level. The model is implemented in a three-dimensional finite element setting to simulate uterus contraction during labor in response to electrical discharges generated by pacemaker cells and propagated within the myometrium via gap junctions. Important clinical factors, such as uterine electrical activity and intrauterine pressure, are predicted using this simulation. The predictions are in agreement with clinically measured data reported in the literature. A parameter study is also carried out to investigate the impact of physiologically related parameters on the uterine contractility.

    Place, publisher, year, edition, pages
    Springer, 2016
    Keyword
    Excitation-contraction model of uterine smooth muscle; Uterus contraction; Intrauterine pressure; Uterine electrical activity
    National Category
    Applied Mechanics
    Identifiers
    urn:nbn:se:liu:diva-121013 (URN)10.1007/s10237-015-0703-z (DOI)000376014800002 ()26162461 (PubMedID)
    Available from: 2015-09-02 Created: 2015-09-02 Last updated: 2018-01-03Bibliographically approved
    4. Identification of the mechanical parameters for the human uterus in vivo using intrauterine pressure measurements
    Open this publication in new window or tab >>Identification of the mechanical parameters for the human uterus in vivo using intrauterine pressure measurements
    2017 (English)In: International Journal for Numerical Methods in Biomedical Engineering, ISSN 2040-7939, E-ISSN 2040-7947, Vol. 33, no 1, 1-11 p.Article in journal (Refereed) Published
    Abstract [en]

    There are limited experimental data to characterize the mechanical response of human myometrium. A method is presented in this work to identify mechanical parameters describing the active response of human myometrium from the in vivo intrauterine pressure measurements. A finite element model is developed to compute the intrauterine pressure during labor in response to an increase in the intracellular calcium ion concentration within myometrial smooth muscle cells. The finite element model provides the opportunity to tune mechanical parameters in order to fit the computed intrauterine pressure to in vivo measurements. Since the model is computationally expensive, a cheaper meta-model is generated to approximate the model response. By fitting the meta-model response to the in vivo measurements, the parameters used to determine the active response of human myometrial smooth muscle are identified.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2017
    Keyword
    human uterine smooth muscle mechanics, intrauterine pressure, parameter identification, response surface methodology
    National Category
    Applied Mechanics Mechanical Engineering
    Identifiers
    urn:nbn:se:liu:diva-121014 (URN)10.1002/cnm.2778 (DOI)000393964900001 ()26915913 (PubMedID)2-s2.0-84962638845 (Scopus ID)
    Note

    At the time of the thesis presentation this publication was in status Manuscript.

    Available from: 2015-09-02 Created: 2015-09-02 Last updated: 2018-01-03Bibliographically approved
  • 23.
    Andersson, Håkan
    et al.
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Science & Engineering. Construct Tools PC AB, Sweden.
    Nordin, Peter
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Science & Engineering.
    Borrvall, Thomas
    DYNAmore Nordic AB, Brigadgatan 5, S-58758 Linkoping, Sweden.
    Simonsson, Kjell
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    Hilding, Daniel
    DYNAmore Nordic AB, Brigadgatan 5, S-58758 Linkoping, Sweden.
    Schill, Mikael
    DYNAmore Nordic AB, Brigadgatan 5, S-58758 Linkoping, Sweden.
    Krus, Petter
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Leidermark, Daniel
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    A co-simulation method for system-level simulation of fluid-structure couplings in hydraulic percussion units2017In: Engineering with Computers, ISSN 0177-0667, E-ISSN 1435-5663, Vol. 33, no 2, 317-333 p.Article in journal (Refereed)
    Abstract [en]

    This paper addresses a co-simulation method for fluid power driven machinery equipment, i.e. oil hydraulic machinery. In these types of machinery, the fluid-structure interaction affects the end-product performance to a large extent, hence an efficient co-simulation method is of high importance. The proposed method is based on a 1D system model representing the fluid components of the hydraulic machinery, within which structural 3D Finite Element (FE) models can be incorporated for detailed simulation of specific sub-models or complete structural assemblies. This means that the fluid system simulation will get a more accurate structural response, and that the structural simulation will get more correct fluid loads at every time step, compared to decoupled analysis. Global system parameters such as fluid flow, performance and efficiency can be evaluated from the 1D system model simulation results. From the 3D FE-models, it is possible to evaluate displacements, stresses and strains to be used in stress analysis, fatigue evaluation, acoustic analysis, etc. The method has been implemented using two well-known simulation tools for fluid power system simulations and FE-simulations, respectively, where the interface between the tools is realised by use of the Functional Mock-up Interface standard. A simple but relevant model is used to validate the method.

  • 24.
    Palm, Elin
    Linköping University, Department of Culture and Communication, Centre for Applied Ethics. Linköping University, Faculty of Arts and Sciences.
    A Declaration of Healthy Dependence: The case of home care2014In: Health Care Analysis, ISSN 1065-3058, E-ISSN 1573-3394, Vol. 22, no 4, 385-404 p.Article in journal (Refereed)
    Abstract [en]

    Aging populations have become a major concern in the developed world and are expected to require novel care strategies. Public policies, health-care regimes and technology developers alike stress the need for a more individualized care to meet the increased demand for care services in response to demographic change. Increasingly, care services are offered to individuals with diseases and or disabilities in their homes by means of Personalized Health-Monitoring (PHM) technologies. PHM-based home care is typically portrayed as the key to a cost-effective future care that better can accommodate the needs of an aging population and promote care recipients’ independence. In light of the emerging technology-based home care, this article sets forth to investigate the significance and implications of a strong emphasis on independence in relation to this novel care form. Notions of independence as used by care planners, care providers and technology developers are examined in relation to ICT-based home care and the reasonableness of independence as an aim for future health-care is critically discussed. In conclusion, the need for a shift from a strong emphasis on independence to a right to healthy dependence is advocated.

  • 25.
    Gupta, M
    et al.
    University West, Trollhättan, Sweden.
    Eriksson, Robert
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Sand, U
    EDR Medeso, Västerås, Sweden.
    Nylén, P
    University West, Trollhättan, Sweden.
    A Diffusion-based Oxide Layer Growth Model Using Real Interface Roughness in Thermal Barrier Coatings for Lifetime Assessment2015In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 271, 181-191 p.Article in journal (Refereed)
    Abstract [en]

    The development of thermo-mechanical stresses during thermal cycling can lead to the formation of detrimental cracks in Atmospheric Plasma Sprayed (APS) Thermal Barrier Coatings systems (TBCs). These stresses are significantly increased by the formation of a Thermally Grown Oxide (TGO) layer that forms through the oxidation of mainly aluminium in the bondcoat layer of the TBC. As shown in previous work done by the authors, the topcoat–bondcoat interface roughness plays a major role in the development of the stress profile in the topcoat and significantly affects the lifetime of TBCs. This roughness profile varies as the TGO layer grows and changes the stress profile in the topcoat leading to crack propagation and thus failure.

    In this work, a two-dimensional TGO growth model is presented, based on oxygen and aluminium diffusion–reaction equations, using real interface profiles extracted from cross-section micrographs. The model was first validated by comparing the TGO profiles artificially created by the model to thermally cycled specimens with varying interface roughness. Thereafter, stress profiles in the TBC system, before and after the TGO layer growth, were estimated using a finite element modelling model described in previous work done by the authors. Three experimental specimens consisting of the same chemistry but with different topcoat–bondcoat interface roughness were studied by the models and the stress state was compared to the lifetimes measured experimentally. The combination of the two models described in this work was shown to be an effective approach to assess the stress behaviour and lifetime of TBCs in a comparative way.

  • 26.
    Khayyeri, Hanifeh
    et al.
    Lund University, Sweden.
    Gustafsson, Anna
    Lund University, Sweden.
    Heuijerjans, Ashley
    Eindhoven University of Technology, Netherlands.
    Matikainen, Marko K.
    Lappeenranta University of Technology, Finland.
    Julkunen, Petro
    Kuopio University Hospital, Finland; University of Eastern Finland, Finland.
    Eliasson, Pernilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Aspenberg, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Isaksson, Hanna
    Lund University, Sweden.
    A Fibre-Reinforced Poroviscoelastic Model Accurately Describes the Biomechanical Behaviour of the Rat Achilles Tendon2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 6, e0126869Article in journal (Refereed)
    Abstract [en]

    Background Computational models of Achilles tendons can help understanding how healthy tendons are affected by repetitive loading and how the different tissue constituents contribute to the tendons biomechanical response. However, available models of Achilles tendon are limited in their description of the hierarchical multi-structural composition of the tissue. This study hypothesised that a poroviscoelastic fibre-reinforced model, previously successful in capturing cartilage biomechanical behaviour, can depict the biomechanical behaviour of the rat Achilles tendon found experimentally. Materials and Methods We developed a new material model of the Achilles tendon, which considers the tendons main constituents namely: water, proteoglycan matrix and collagen fibres. A hyperelastic formulation of the proteoglycan matrix enabled computations of large deformations of the tendon, and collagen fibres were modelled as viscoelastic. Specimen-specific finite element models were created of 9 rat Achilles tendons from an animal experiment and simulations were carried out following a repetitive tensile loading protocol. The material model parameters were calibrated against data from the rats by minimising the root mean squared error (RMS) between experimental force data and model output. Results and Conclusions All specimen models were successfully fitted to experimental data with high accuracy (RMS 0.42-1.02). Additional simulations predicted more compliant and soft tendon behaviour at reduced strain-rates compared to higher strain-rates that produce a stiff and brittle tendon response. Stress-relaxation simulations exhibited strain-dependent stress-relaxation behaviour where larger strains produced slower relaxation rates compared to smaller strain levels. Our simulations showed that the collagen fibres in the Achilles tendon are the main load-bearing component during tensile loading, where the orientation of the collagen fibres plays an important role for the tendons viscoelastic response. In conclusion, this model can capture the repetitive loading and unloading behaviour of intact and healthy Achilles tendons, which is a critical first step towards understanding tendon homeostasis and function as this biomechanical response changes in diseased tendons.

  • 27.
    Bergqvist, Göran
    et al.
    Private practice, Norrköping, Sweden.
    Simonsson, Kjell
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Rydberg, Kristoffer
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Johansson, Fredrik
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Dérand, Tore
    Department of Dental Technology and Dental Materials Science, Faculty of Odontology, Malmö University, Malmö, Sweden.
    A finite element analysis of stress distribution in bone tissue surrounding uncoupled or splinted dental implants2008In: Clinical Implant Dentistry and Related Research, ISSN 1523-0899, E-ISSN 1708-8208, Vol. 10, no 1, 40-46 p.Article in journal (Refereed)
    Abstract [en]

    Background: Several studies on one-stage surgery in the treatment of the edentulous maxilla with implant-supported fixed prostheses have reported problems with removable provisional prostheses, which can load the implants in an uncontrollable manner during healing, and jeopardize healing. Immediate splinting of the implants with a fixed provisional prosthesis has been proposed to protect the bone-implant interface.

    Purpose: This study used the finite element method (FEM) to simulate stresses induced in bone tissue surrounding uncoupled and splinted implants in the maxilla because of bite force loading, and to determine whether the differences in these stress levels are related to differences in observed bone losses associated with the two healing methods.

    Materials and Methods: Stress levels in the maxilla were studied using the FEM program TRINITAS (Institute of Technology, Linköping University, Linköping, Sweden) in which all phases – preprocessing/modeling, equation solving, and postprocessing/evaluation – were simulated.

    Results: Stress levels in bone tissue surrounding splinted implants were markedly lower than stress levels surrounding uncoupled implants by a factor of nearly 9.

    Conclusion: From a mechanical viewpoint, FEM simulation supports the hypothesis that splinting reduces damage evolution in bone tissue, which agrees with clinical observations.

  • 28.
    Thore, Carl-Johan
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    Holmberg, Erik
    Saab AB, Linkoping, Sweden.
    Klarbring, Anders
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    A general framework for robust topology optimization under load-uncertainty including stress constraints2017In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 319Article in journal (Refereed)
    Abstract [en]

    We present a worst-case approach for topology optimization under load-uncertainty based on a general problem formulation involving maxima of quadratic functions of an uncertain load vector as both objective and constraints. The problem is reformulated as a non-linear semi-definite program which can be solved efficiently. An important special case of the general problem formulation is worst-case compliance minimization under worst-case stress constraints which is illustrated by numerical examples. (C) 2017 Elsevier B.V. All rights reserved.

  • 29.
    Chason, E.
    et al.
    Brown University, USA.
    Karlson, M.
    Brown University, USA.
    Colin, J. J.
    University of Poitiers, France.
    Magnfält, Daniel
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Sarakinos, Kostas
    Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering.
    Abadias, G.
    University of Poitiers, France.
    A kinetic model for stress generation in thin films grown from energetic vapor fluxes2016In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 119, no 14, 145307Article in journal (Refereed)
    Abstract [en]

    We have developed a kinetic model for residual stress generation in thin films grown from energetic vapor fluxes, encountered, e.g., during sputter deposition. The new analytical model considers sub-surface point defects created by atomic peening, along with processes treated in already existing stress models for non-energetic deposition, i.e., thermally activated diffusion processes at the surface and the grain boundary. According to the new model, ballistically induced subsurface defects can get incorporated as excess atoms at the grain boundary, remain trapped in the bulk, or annihilate at the free surface, resulting in a complex dependence of the steady-state stress on the grain size, the growth rate, as well as the energetics of the incoming particle flux. We compare calculations from the model with in situ stress measurements performed on a series of Mo films sputter-deposited at different conditions and having different grain sizes. The model is able to reproduce the observed increase of compressive stress with increasing growth rate, behavior that is the opposite of what is typically seen under non-energetic growth conditions. On a grander scale, this study is a step towards obtaining a comprehensive understanding of stress generation and evolution in vapor deposited polycrystalline thin films. Published by AIP Publishing.

  • 30.
    McKelvey, Tomas
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Least Squares Interpretation of Sub-Space Methods for System Identification1996In: Proceedings of the 35th IEEE Conference on Decision and Control, 1996, 335-342 vol.1 p.Conference paper (Refereed)
    Abstract [en]

    So called subspace methods for direct identification of linear models in state space form have drawn considerable interest. The algorithms consist of series of quite complex projections, and it is not so easy to intuitively understand how they work. They have also defied, so far, complete asymptotic analysis of their stochastic properties. This contribution describes an interpretation of how they work. It specifically deals with how consistent estimates of the dynamics can be achieved, even though correct predictors are not used. We stress how the basic idea is to focus on the estimation of the state-variable candidates-the k-step ahead output predictors.

  • 31.
    Ljung, Lennart
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    McKelvey, Tomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Least Squares Interpretation of Sub-Space Methods for System Identification1996Report (Other academic)
    Abstract [en]

    So called subspace methods for direct identification of linear models in state space form have drawn considerable interest. The algorithms consist of series of quite complex projections, and it is not so easy to intuitively understand how they work. They have also defied, so far, complete asymptotic analysis of their stochastic properties. This contribution describes an interpretation of how they work. It specifically deals with how consistent estimates of the dynamics can be achieved, even though correct predictors are not used. We stress how the basic idea is to focus on the estimation of the state-variable candidates-the k-step ahead output predictors.

  • 32.
    Stålhand, Jonas
    et al.
    Linköping University, Department of Management and Engineering, Mechanics. Linköping University, The Institute of Technology.
    Klarbring, Anders
    Linköping University, Department of Management and Engineering, Mechanics. Linköping University, The Institute of Technology.
    Holzapfel, Gerhard A
    Graz University of Technology, Institute of Biomechanics, Center of Biomedical Engineering / Royal Institute of Technology, Department of Solid Mechanics, School of Engineering Sciences.
    A mechanochemical 3D continuum model for smooth muscle contraction under finite strains2011In: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 268, no 1, 120-130 p.Article in journal (Refereed)
    Abstract [en]

    This paper presents a modelling framework in which the mechanochemical properties of smooth muscle cells may be studied. The activation of smooth muscles is considered in a three-dimensional continuum model which is key to realistically capture the function of hollow organs such as blood vessels. On the basis of a general thermodynamical framework the mechanical and chemical phases are specialized in order to quantify the coupled mechanochemical process. A free-energy function is proposed as the sum of a mechanical energy stored in the passive tissue, a coupling between the mechanical and chemical kinetics and an energy related purely to the chemical kinetics and the calcium ion concentration. For the chemical phase it is shown that the cross-bridge model of Hai and Murphy [1988. Am. J. Physiol. Cell Physiol. 254, C99–C106] is included in the developed evolution law as a special case. In order to show the specific features and the potential of the proposed continuum model a uniaxial extension test of a tissue strip is analysed in detail and the related kinematics and stress–stretch relations are derived. Parameter studies point to coupling phenomena; in particular the tissue response is analysed in terms of the calcium ion level. The model for smooth muscle contraction may significantly contribute to current modelling efforts of smooth muscle tissue responses.

  • 33.
    Renner, Johan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    Gårdhagen, Roland
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    Ebbers, Tino
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Heiberg, Einar
    Department of Clinical Physiology, Lund University Hospital, Sweden.
    Länne, Toste
    Linköping University, Department of Medicine and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Karlsson, Matts
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, The Institute of Technology.
    A method for subject specific estimation of aortic wall shear stress2009In: WSEAS Transactions on Biology and Biomedicine, ISSN 1109-9518, Vol. 6, no 3, 49-57 p.Article in journal (Refereed)
    Abstract [en]

    Wall shear stress (WSS) distribution in the human aorta is a highly interesting hemodynamic factor for atherosclerosis development. We present a magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) based subject specific WSS estimation method and demonstrate it on a group of nine healthy volunteers (males age 23.6 ± 1.3 years). In all nine subjects, the aortic blood flow was simulated in a subject specific way, where the 3D segmented geometries and inflow profiles were obtained using MRI. No parameter settings were tailored using data from the nine subjects. Validation was performed by comparing CFD gained velocity with magnetic resonance imaging (MRI) velocity measurements. CFD and MRI velocity profiles were comparable, but the temporal variations of the differences during the cardiac cycle were significant. Spatio-temporal analyzes on the WSS distribution showed a strong subject specific influence. Subject specific models are decisive to estimate WSS distribution.

  • 34.
    Edlund, Ulf
    et al.
    Linköping University, Department of Management and Engineering, Mechanics . Linköping University, The Institute of Technology.
    Schmidt, Peter
    Linköping University, Department of Management and Engineering, Mechanics . Linköping University, The Institute of Technology.
    Roguet , E
    ENSMA, France.
    A model of an adhesively bonded joint with elastic-plastic adherends and a softening adhesive2009In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 198, no 5-8, 740-752 p.Article in journal (Refereed)
    Abstract [en]

    This paper deals with the generalization of a model of an adhesively bonded joint with the aim to allow elastic-plastic adherends. In the model of the joint that we extend, the thinness of the bodies and the low Youngs modulus of the adhesive were used to obtain a simplified model where the parts are described as material surfaces. We formulate an elastic-plastic material model with isotropic hardening expressed in the generalized stress and strain measures used for the surface description of the joint. The finite element formulation and the numerical treatment of the constitutive law are discussed. Numerical results showing the accuracy of the proposed treatment of the adherends are presented. Two failure load computations, using a softening material model for the adhesive, are presented and compared with experiments. The results show the importance of taking into account potential plastic deformations in the adherends in failure load computations.

  • 35.
    Ewest, D.
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering. Siemens Ind Turbomachinery AB, Sweden.
    Almroth, P.
    Siemens Ind Turbomachinery AB, Sweden.
    Sjodin, B.
    Siemens Ind Turbomachinery AB, Sweden.
    Simonsson, Kjell
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    Leidermark, Daniel
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, Faculty of Science & Engineering.
    Moverare, Johan
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    A modified compliance method for fatigue crack propagation applied on a single edge notch specimen2016In: International Journal of Fatigue, ISSN 0142-1123, E-ISSN 1879-3452, Vol. 92, 61-70 p.Article in journal (Refereed)
    Abstract [en]

    Crack length measurements with high accuracy are often difficult to achieve during fatigue crack propagation testing under non-isothermal conditions. In this work a modified approach to the compliance method defined in e.g. ASTM E647 is described, which is better suited for high loads, varying temperatures and for taking the scatter in Youngs modulus into account. A numerical finite element study is performed for a single edge notch specimen, to investigate the influence of initiation locations on the accuracy of the method. The change in cracked area versus change in stiffness for three different cases are numerically shown to collapse to one curve, i.e. the result is not significantly affected by how the crack is initiated. The numerical study is compared to results from two experiments using different materials, with heat tinting during the tests for extracting snapshots of the crack fronts. A good agreement between the experiments and the numerical study is shown. A new compliance curve and a new geometry function for the stress intensity factor is proposed for the single edge notch specimen. (C) 2016 Elsevier Ltd. All rights reserved.

  • 36.
    Wang, Y D
    et al.
    Studsvik Neutron Research Lab Uppsala university.
    Peng, Ru
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    McGreevy, R L
    Studsvik Neutron Research Lab Uppsala university.
    A novel method for constructing the mean field of grain-orentation-dependent residual stress2001In: Philosophical magazine letters : physics of condensed matter, Vol. 81, no 3, 153-163 p.Article in journal (Refereed)
  • 37.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Becker, Richard
    Studsvik Nuclear AB.
    Dozaki, Koji
    The Japan Atomic Power Company.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    A Novel Oxide Characterization Method of Nickel Base Alloy 600 Used in Nuclear Plant Reactors2013In: / [ed] F. Marquis, Hoboken, NJ, USA: John Wiley & Sons, 2013, 415- p.Conference paper (Refereed)
    Abstract [en]

    The Alloy 600 is a polycrystalline nickel base alloy used in pressurized water reactors (PWR) of nuclear power plants. Long term exposure of the alloy to primary water of PWR generates an oxide film that strongly influences the stress corrosion cracking behavior of the alloy. Recently, it has been shown that the oxide film structure, composition and thickness depend on the dissolved hydrogen content in the primary water. In this work we have explored a novel approach which enables a high spatial resolution oxide thickness measurement by nanomechanical testing. Oxide films have been grown on Alloy 600 specimens exposed between 5000 and 35000 hours at 320-330°C with hydrogen levels in the range 5 to 25 mL H2/kg H2O. A Triboindenter TI-950 from Hysitron was used to measure the change of nanomechanical properties in polished cross-sections. The increase of hardness has been correlated to the presence of oxides.

  • 38.
    Tinghög, Petter
    et al.
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Richt, Bengt
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Eriksson, Mimmi
    Centre for Social Research on Alcohol and Drugs (SoRAD), Stockholm University, Stockholm, Sweden.
    Nordenfelt, Lennart
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    A phenomenological approach to the study of stress among immigrants: the case of Iraqi and Iranian women in SwedenManuscript (Other academic)
    Abstract [en]

    This study begins with the outlining of a general phenomenological theory of stress, which subsequently is applied to eleven Iraqi and Iranian migrant women’s own accounts of life in Sweden. The analysis of the interviews suggested that domestic disputes and intergenerational conflicts may become particularly stressful in that they are often amplified by incompatible Western and Non‐Western representations. The detected stressful experiences are analysed and structured to elucidate their character. Finally, a typology of stressful experiences in the new environment based on the distinctions between immigrant/minority‐specific and non‐immigrant/‐ minority‐specific stress, as well as between culturogenic and non‐culturogenic stress, is presented and defended.

  • 39.
    Roberg, Karin
    et al.
    Linköping University, Department of Neuroscience and Locomotion, Pathology. Linköping University, Faculty of Health Sciences.
    Öllinger, Karin
    Linköping University, Department of Neuroscience and Locomotion, Pathology. Linköping University, Faculty of Health Sciences.
    A Pre-embedding Technique for Immunocytochemical Visualization of Cathepsin D in Cultured Cells Subjected to Oxidative Stress1998In: Journal of Histochemistry and Cytochemistry, ISSN 0022-1554, E-ISSN 1551-5044, Vol. 46, no 3, 411-418 p.Article in journal (Refereed)
    Abstract [en]

    We describe a pre-embedding immunocytochemical method for visualization of the lysosomal enzyme cathepsin D in cultured cells. The protein was demonstrated at both light and electron microscopic levels by neutral-pH silver enhancement of ultrasmall (0.8-nm) gold particles conjugated to the antibodies. The best morphological preservation and the highest labeling density were achieved by initial fixation for 20 min at 4C in 4% paraformaldehyde (PFA) and 0.05% glutaraldehyde (GA) in 0.15 M sodium cacodylate buffer, followed by permeabilization in sodium borohydride. Three cell types were used: human foreskin fibroblasts, histocytic lymphoma (J-774) cells, and primary rat heart myocytes. In all three, cathepsin D was demonstrated in lysosome-like structures. The rat heart myocytes were also exposed to the redox cycling substance naphthazarin (5,8-dihydroxy-1,4-naph-thoquinone) to induce oxidative stress. This was done for such a short period of time that the cells initially did not show any signs of morphological damage and retained normal plasma membrane stability, although an early and clear redistribution of cathepsin D from membrane-bound structures to the cytosol was apparent. This redistribution was followed by cell degeneration and, eventually, by cell death.

  • 40. Środa, Magdalena
    et al.
    Rogowska-Stangret, Monika
    Cielemecka, Olga
    A Quest for Feminist Space and Time2014In: Women - A Cultural Review, ISSN 0957-4042, E-ISSN 1470-1367, Vol. 25, no 1, 114-122 p.Article in journal (Refereed)
    Abstract [en]

    This article offers an investigation of practical and political aspects of new materialism on the basis of texts accepted for publication in Women: A Cultural Review. The authors emphasize various political strategies that appear in the collected essays; above all they stress the practical aspects of theory itself. Theory as praxis is a concept inspired by contemporary philosophers such as Georges Canguilhem, Gilles Deleuze, Michel Foucault and Donna Haraway. It can also be the basis for a politics of location and it highlights the importance of being situated in specific sociocultural, historical, local and geographical contexts. The authors raised the question of the potential alliances between their specific, Polish context and the possibility of participating in and creating a broader feminist movement, which proves to be possible thanks to a variety of perspectives that are considered important and worth considering in new materialism. In the article, the Polish Kongres Kobiet (‘Women's Congress’) initiative is presented as a platform for feminist activity which combines various kinds of political, social and cultural interests, concerns and goals. Along with the importance of space for feminist politics, the authors consider time as a crucial constituent of feminist activism. Both rethinking the past—tradition, heritage, history—and directing reflection towards the future hopes, possibilities, politics and theories, constitute important characteristics of the new materialism approach. The authors conclude by introducing the notion of the ‘politics of squatting’, which serves as a metaphor for a feminist quest for space and time.

  • 41.
    Mörelius, Eva-lotta
    et al.
    Linköping University, Department of Social and Welfare Studies, Division of Health, Activity and Care. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Örtenstrand, Annika
    Karolinska Institutet.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Frostell, Anneli
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    A randomised trial of continuous skin-to-skin contact after preterm birth and the effects on salivary cortisol, parental stress, depression, and breastfeeding2015In: Early Human Development, ISSN 0378-3782, E-ISSN 1872-6232, Vol. 91, no 1, 63-70 p.Article in journal (Refereed)
    Abstract [en]

    AIM:

    To evaluate the effects of almost continuous skin-to-skin contact (SSC) on salivary cortisol, parental stress, parental depression, and breastfeeding.

    STUDY DESIGN:

    This is a randomised study engaging families of late preterm infants (32-35weeks gestation). Salivary cortisol reactivity was measured in infants during a nappy change at one month corrected age, and in infants and mothers during still-face at four month corrected age. Both parents completed the Swedish Parenthood Stress Questionnaire (SPSQ) at one month and the Edinburgh Postnatal Depression Scale (EPDS) at one and four months. Ainsworth's sensitivity scale was used to control for parental sensitivity.

    SUBJECTS:

    Thirty-seven families from two different neonatal care units in Sweden, randomised to either almost continuous SSC or standard care (SC).

    RESULTS:

    Infants randomised to SSC had a lower salivary cortisol reactivity at one month (p=0.01). There was a correlation between the mothers' and the preterm infants' salivary cortisol levels at four months in the SSC group (ρ=0.65, p=0.005), but not in the SC group (ρ=0.14, p=0.63). Fathers in SSC scored lower on the SPSQ sub-scale spouse relationship problems compared to fathers in SC (p<0.05).

    CONCLUSIONS:

    Almost continuous SSC decreases infants' cortisol reactivity in response to handling, improves the concordance between mothers' and infants' salivary cortisol levels, and decreases fathers' experiences of spouse relationship problems.

  • 42.
    Hesser, Hugo
    et al.
    Linköping University, The Swedish Institute for Disability Research. Linköping University, Department of Behavioural Sciences and Learning, Disability Research. Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Gustafsson, Tore
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    Lundén, Charlotte
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    Henrikson, Oskar
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    Fattahi, Kidjan
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    Johnsson, Erik
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    Westin Zetterqvist, Vendela
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
    Carlbring, Per
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Mäki-Torkko, Elina
    Linköping University, Department of Clinical and Experimental Medicine, Technical Audiology. Linköping University, Faculty of Health Sciences.
    Kaldo, Viktor
    Department of Clinical Neuroscience, Psychiatric Section, Karolinska Institutet, Stockholm, Sweden.
    Andersson, Gerhard
    Linköping University, The Swedish Institute for Disability Research. Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    A Randomized Controlled Trial of Internet-Delivered Cognitive Behavior Therapy and Acceptance and Commitment Therapy in the Treatment of Tinnitus2012In: Journal of Consulting and Clinical Psychology, ISSN 0022-006X, E-ISSN 1939-2117, Vol. 80, no 4, 649-661 p.Article in journal (Refereed)
    Abstract [en]

    Objective: Our aim in this randomized controlled trial was to investigate the effects on global tinnitus severity of 2 Internet-delivered psychological treatments, acceptance and commitment therapy (ACT) and cognitive behavior therapy (CBT), in guided self-help format. Method: Ninety-nine participants (mean age = 48.5 years; 43% female) who were significantly distressed by tinnitus were recruited from the community. Participants were randomly assigned to CBT (n = 32), ACT (n = 35), or a control condition (monitored Internet discussion forum; n = 32), and they were assessed with standardized self-report measures (Tinnitus Handicap Inventory; Hospital Anxiety and Depression Scale; Quality of Life Inventory; Perceived Stress Scale; Tinnitus Acceptance Questionnaire) at pre-, posttreatment (8 weeks), and 1-year follow-up. Results: Mixed-effects linear regression analysis of all randomized participants showed significant effects on the primary outcome (Tinnitus Handicap Inventory) for CBT and for ACT compared with control at posttreatment (95% CI [-17.03, -2.94], d = 0.70, and 95% CI [-16.29, -2.53], d = 0.68, respectively). Within-group effects were substantial from pretreatment through 1-year-follow-up for both treatments (95% CI [-44.65, -20.45], d = 1.34), with no significant difference between treatments (95% CI [-14.87, 11.21], d = 0.16). Conclusions: Acceptance-based procedures may be a viable alternative to traditional CBT techniques in the management of tinnitus. The Internet can improve access to psychological interventions for tinnitus.

  • 43.
    Salomonsson, Bjorn
    et al.
    Karolinska Institute.
    Sandell, Rolf
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    A RANDOMIZED CONTROLLED TRIAL OF MOTHER-INFANT PSYCHOANALYTIC TREATMENT: I. OUTCOMES ON SELF-REPORT QUESTIONNAIRES AND EXTERNAL RATINGS2011In: INFANT MENTAL HEALTH JOURNAL, ISSN 0163-9641, Vol. 32, no 2, 207-231 p.Article in journal (Refereed)
    Abstract [en]

    Mother infant relationship disturbances occur in three domains: maternal distress, infant functional problems, and relationship difficulties. They constitute common clinical problems. In Sweden, they are usually handled by nurses as part of public Child Health Centre care. Severe cases are referred to child psychiatry services. This randomized controlled trial compared two groups of mother infant dyads in a Stockholm sample. One received only Child Health Centre care (the "CHCC" group) while the other received mother infant psychoanalytic treatment plus CHCC (the "MIP" group). Eighty dyads of mothers and infants under I years of age where the mothers had serious concerns about themselves in their role as mothers, their infants well-being, or the mother baby relationship were randomly selected for either the MIP or the CHCC group. The primary outcomes were mother-reported depression, mother-reported infant functional problems, and interviewer-based relationship assessments, all at 6 months after joining the project. Secondary outcomes were mother-reported stress and general psychic distress, externally rated video-recorded interactions, and the consumption of healthcare at the CHC, again all after 6 months. Intent-to-treat analyses of Treatment x Time effects significantly favored MIP treatment for maternal depression, mother infant relationships, and maternal sensitivity. Effects were nearly significant on maternal stress, but nonsignificant on mother-reported infant functional problems, general psychic distress, maternal interactive structuring and nonintrusiveness, infant responsiveness and involvement, and healthcare consumption. MIP treatment improved mother infant relationships and maternal sensitivity and depression, all of which are known to influence child development. If effects persist and are reproduced, MIP treatment holds promise for more widespread use.

  • 44.
    Salomonsson, Bjorn
    et al.
    Karolinska institutet.
    Sandell, Rolf
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences.
    A RANDOMIZED CONTROLLED TRIAL OF MOTHER-INFANT PSYCHOANALYTIC TREATMENT: II. PREDICTIVE AND MODERATING INFLUENCES OF QUALITATIVE PATIENT FACTORS2011In: INFANT MENTAL HEALTH JOURNAL, ISSN 0163-9641, Vol. 32, no 3, 377-404 p.Article in journal (Refereed)
    Abstract [en]

    A randomized control trial was performed on 75 dyads in Stockholm, Sweden, with infants under I years. It recruited mothers who worried about the babies, themselves as mothers, and/or the mother-baby relationship. Two groups of mother-infant dyads were compared. One received only Child Health Centre care (the "CHCC" group) while the other received mother-infant psychoanalytic treatment plus CHCC (the "MIP" group). Significant treatment effects were found on mother-reported depression, interviewer-rated dyadic relationship qualities and externally rated maternal sensitivity, and near-significant effects on mother-reported stress, all in favor of MIP. The objective of this study is to investigate the predictive and moderating influences on outcomes by qualitatively assessed maternal and infant characteristics. The qualitative factors covered maternal suitability for psychoanalysis, and "ideal types" of mother and child, respectively. Outcome measures from two interviews with a 6-month interval were depression (Edinburgh Postnatal Depression Scale (J. Cox, J. Holden, andamp; R. Sagovsky, 1987), stress (Swedish Parental Stress Questionnaire (M. Ostberg, B. Hagekull, andamp; S. Wettergren, 1997), distress (Swedish Symptom Checklist-90 (SCL-90; L.R. Derogatis, I 994; M. Fridell, Z. Cesarec, M. Johansson, andamp; S. Mailing Thorsen, 2002) and infant social and emotional functioning (Ages and Stages Questionnaire: Social-Emotional (J. Squires, D. Bricker, K. Heo, andamp; E. Twombly, 2002), relationship qualities (Parent-Infant Global Assessment Scale (PIR-GAS; ZERO TO THREE, 2005), and videotaped interactions (Emotional Availability Scales, Z. Biringen, J.L. Robinson, andamp; R.N. Emde, 1998). Suitability for psychoanalysis predicted outcome only on the PIR-GAS. Two overarching maternal ideal types were created, reflecting their attitude to the psychoanalytic process: "Participators" and "Abandoned." The Participators benefited more from MIP than they did From CHCC on maternal interactive sensitivity. A contrasting, but nonsignificant, pattern was found among the Abandoned mothers. Two ideal types of babies emerged: those "Affected" and "Unaffected" by the disturbance, respectively. Among Affected babies, dyadic relationships and sensitivity among their mothers improved significantly more from MIP than they did from CHCC. The superior effects of MIP applied especially to Participator mothers and Affected infants. For Abandoned mothers and Unaffected infants, CHCC seemed to be of equal value.

  • 45.
    Keselman, Boris
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Vergara Valgañon, Marta
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Nyberg, Sofia
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Nyström, Fredrik H
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Endocrinology.
    A randomized cross-over study of the acute effects of running 5 km on glucose, insulin, metabolic rate, cortisol and Troponin T2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 6, e0179401Article in journal (Refereed)
    Abstract [en]

    Background We aimed to study the impact by running 5 km, at maximal speed, on the normal variations of metabolic variables related to glucose, insulin, insulin sensitivity, cortisol, glucagon, Troponin T and metabolic rate. Material and methods Five women and 12 men 25.7 +/- 5.2 years of age with a body-mass-index of 22.5 +/- 2.3 kg/m(2) where recruited to run 5 km at individual maximal speed in the morning, and to a corresponding day of rest, followed by standardized breakfast and lunch meals. Blood sampling and measurement of indirect calorimetry were done before and after meals. The participants were randomized regarding the order of the two trial-days in this cross-over study. Results Insulin and cortisol levels were higher, and insulin sensitivity was lower, on the race-day compared with the day of rest (linear mixed model: pamp;lt;0.0001 for all three analyses). However, glucose levels and metabolic rate did not differ between the two trial days (p = 0.29 and p = 0.53, respectively). When analyzing specific time-points we found that glucose increased from 5.01 +/- 0.37 mmol/l to 6.36 +/- 1.3 mmol/l, pamp;lt;0.0001, by running, while serum insulin concomitantly increased from 42 21 to 90 54 pmo1/1, pamp;lt;0.0001. In accordance, the QUICKI index of serum sensitivity, 1/(log(10)insulin+log(10)glucose), was lowered post-race, pamp;lt;0.0001. Serum cortisol levels increased from 408 137 nmol/l to 644 171 nmol/l, pamp;lt;0.0001, post-race while serum glucagon levels were unaffected. Troponin T was detectable in serum post-race in 12 out of the 17 participants and reached or surpassed the clinical reference level of 15 ng/l in three subjects. Post-race electrocardiograms displayed no pathologies. Conclusions Relatively short running-races can apparently induce a reduction in insulin sensitivity that is not fully compensated by concomitantly increased insulin secretion intended to ensure euglycemia. Since also Troponin T was detected in plasma in a majority of the participants, our data suggest that it is possible to induce considerable metabolic stress by running merely 5 km, when striving for maximal speed.

  • 46.
    Brandouy, Olivier
    et al.
    Sorbonne Grad Business Sch, France .
    Corelli, Angelo
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Veryzhenko, Iryna
    ENSAM Paristech, France .
    Waldeck, Roger
    Telecom Bretagne, France .
    A re-examination of the "zero is enough" hypothesis in the emergence of financial stylized facts2012In: Journal of Economic Interaction and Coordination, ISSN 1860-711X, E-ISSN 1860-7128, Vol. 7, no 2, 223-248 p.Article in journal (Refereed)
    Abstract [en]

    In recent years, a growing literature has claimed that the market microstructure is sufficient to generate the so-called stylized facts without any reference to the behaviour of market players. Indeed, qualitative stylized-facts can be generated with zero-intelligence traders (ZITs) but we stress that they are without any quantitative predictive power. In this paper we show that in most of the cases, such qualitative stylized facts hide unrealistic price motions at the intraday level and ill-calibrated return processes as well. To generate realistic price motions and return series with adequate quantitative values is out-of-reach using pure ZIT populations. To do so, one must increasingly constrain agents choices to a point where it is hard to claim that their behaviour is completely random. In addition we show that even with highly constrained ZIT agents, one cannot reproduce real time series from these. Except in a few cases, first order moments of ZITs never equal real data ones. We therefore claim that stylized facts produced by means of ZIT agents are useless for financial engineering.

  • 47.
    Thollander, Patrik
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Kimura, Osamu
    Central Research Institute Elect Power Ind, Japan.
    Wakabayashi, Masayo
    Central Research Institute Elect Power Ind, Japan.
    Rohdin, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    A review of industrial energy and climate policies in Japan and Sweden with emphasis towards SMEs2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 50, 504-512 p.Article, review/survey (Refereed)
    Abstract [en]

    The threat of increased global warming resulting from the use of fossil fuels stresses decision-makers to formulate and adopt policies towards different sectors of the economy. In light of the great earthquake in Japan 2011, energy efficiency also plays an important role in meeting the challenge of power supply shortage. Energy policies towards industry are of particular importance as a major part of the energy in the economy is used in industrial production. The number of papers investigating and presenting experience from energy end-use policies are scarce. Furthermore, for those present, they often only include a very brief analysis. From a public point of view, evaluations of energy programs are of major importance to measure the performance of the programs. From an energy policy designer point of view, it is of major importance to not only see the cost-effectiveness of the policy but also to understand the fundamental mechanisms for the success or failure of an industrial energy program, in order to learn how to improve future programs. The aim of this paper is to present a review of energy end-use policy instrument in Japan and Sweden towards the industrial sector from 1990 to 2014, with special emphasis on industrial SMEs. From the results presented some general-conclusions can be made, (1) results show that the cost-effectiveness differs substantially between the evaluated programs, and (2) that from a governmental point of view, subsidies towards energy audit programs seem like the most cost-effective policy. In addition to this (3) the results from the review also stress the importance of a clear strategy for every energy program on how the program is going to be evaluated, ex-ante or ex-post, and how the performance of the program is to be measured. This structure should be included from the start of the program. (C) 2015 Elsevier Ltd. All rights reserved.

  • 48.
    Greczynski, Grzegorz
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Bolz, S.
    CemeCon AG, Germany.
    Koelker, W.
    CemeCon AG, Germany.
    Schiffers, Ch.
    CemeCon AG, Germany.
    Lemmer, O.
    CemeCon AG, Germany.
    Greene, Joseph E
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology. University of Illinois, IL 61801 USA; University of Illinois, IL 61801 USA.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    A review of metal-ion-flux-controlled growth of metastable TiAlN by HIPIMS/DCMS co-sputtering2014In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 257, 15-25 p.Article in journal (Refereed)
    Abstract [en]

    We review results on the growth of metastable Ti1-xAlxN alloy films by hybrid high-power pulsed and dc magnetron co-sputtering (HIPIMS/DCMS) using the time domain to apply substrate bias either in synchronous with the entire HIPIMS pulse or just the metal-rich portion of the pulse in mixed Ar/N-2 discharges. Depending upon which elemental target, Ti or Al, is powered by HIPIMS, distinctly different film-growth kinetic pathways are observed due to charge and mass differences in the metal-ion fluxes incident at the growth surface. Al+ ion irradiation during Al-HIPIMS/Ti-DCMS at 500 degrees C, with a negative substrate bias V-s = 60 V synchronized to the HIPIMS pulse (thus suppressing Ar+ ion irradiation due to DCMS), leads to single-phase NaCl-structure Ti1-xAlxN films (x less than= 0.60) with high hardness (greater than30 GPa with x greater than 0.55) and low stress (0.2-0.8 GPa compressive). Ar+ ion bombardment can be further suppressed in favor of predominantly Al+ ion irradiation by synchronizing the substrate bias to only the metal-ion-rich portion of the Al-HIPIMS pulse. In distinct contrast Ti-HIPIMS/Al-DCMSTi1-xAlxN layers grown with Ti+/Ti2+ metal ion irradiation and the same HIPIMS-synchronized V-s value, are two-phase mixtures, NaCl-structure Ti1-xAlxN plus wurtzite AlN, exhibiting low hardness (similar or equal to 18 GPa) with high compressive stresses, up to -3.5 GPa. In both cases, film properties are controlled by the average metal-ion momentum per deposited atom less thanp(d)greater than transferred to the film surface. During Ti-HIPIMS, the growing film is subjected to an intense flux of doubly-ionized Ti2+, while Al2+ irradiation is insignificant during Al-HIPIMS. This asymmetry is decisive since the critical less thanp(d)greater than limit for precipitation of w-AlN, 135 [eV-amu](1/2), is easily exceeded during Ti-HIPIMS, even with no intentional bias. The high Ti2+ ion flux is primarily due to the second ionization potential (IP2) of Ti being lower than the first IP (IP1) of Ar. New results involving the HIPIMS growth of metastable Ti1-xAlxN alloy films from segmented TiAl targets are consistent with the above conclusions.

  • 49.
    Cammoun, L.
    et al.
    Signal Processing Institute Ecole Polytechnigue Fédérale de Lausanne Switserland.
    Castano-Moraga, C.A.
    University of Las Palmas de Gran Canaria.
    Munoz-Moreno, E.
    Univ. de Valladolid, Spain.
    Sosa-Cabrera, D.
    University of Las Palmas de Gran Canaria.
    Acar, B.
    University Istanbul.
    Rodriguez-Florido, M.A.
    University of Las Palmas de Gran Canaria.
    Brun, Anders
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Thiran, J.P.
    Signal Processing Institute Ecole Polytechnigue Fédérale de Lausanne Switserland.
    A Review of Tensors and Tensor Signal Processing2009In: Tensors in Image Processing and Computer Vision / [ed] S. Aja-Fernandez, R. de Luis Garcia, D. Tao, and X. Li, Springer London, 2009, 1-32 p.Chapter in book (Refereed)
    Abstract [en]

    Tensors have been broadly used in mathematics and physics, since they are a generalization of scalars or vectors and allow to represent more complex properties. In this chapter we present an overview of some tensor applications, especially those focused on the image processing field. From a mathematical point of view, a lot of work has been developed about tensor calculus, which obviously is more complex than scalar or vectorial calculus. Moreover, tensors can represent the metric of a vector space, which is very useful in the field of differential geometry. In physics, tensors have been used to describe several magnitudes, such as the strain or stress of materials. In solid mechanics, tensors are used to define the generalized Hooke’s law, where a fourth order tensor relates the strain and stress tensors. In fluid dynamics, the velocity gradient tensor provides information about the vorticity and the strain of the fluids. Also an electromagnetic tensor is defined, that simplifies the notation of the Maxwell equations. But tensors are not constrained to physics and mathematics. They have been used, for instance, in medical imaging, where we can highlight two applications: the diffusion tensor image, which represents how molecules diffuse inside the tissues and is broadly used for brain imaging; and the tensorial elastography, which computes the strain and vorticity tensor to analyze the tissues properties. Tensors have also been used in computer vision to provide information about the local structure or to define anisotropic image filters.

  • 50.
    Sim, Patrick Puay-I
    Linköping University, Department of Behavioural Sciences and Learning.
    A Sociocultural Investigation of Learning and Transition in SFEC2007Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    With the advent of globalisation driving the People.s Republic of China to embrace its future, the local government has shown great enthusiasm promulgating one of the oldest industries. Foreign higher educational providers that operate in China through the mode of joint venture cooperatives between a Chinese and foreign institution of higher learning are becoming increasingly .knowledgeable-hungry. public or private universities and colleges. Such operations commonly known as Sino-foreign educational cooperatives

    (SFEC), are hotly spawned on the mainland, enrolling Chinese students through the division of responsibilities, roles and resources. The Chinese party is mostly responsible for the hardware support, supplying facilities and logistics as the part of the bargain, whereas the foreign party provides the intellectual software of academic programs. The locus of this qualitative study aims to present and investigate a distinct phenomenon of learning in SFEC through the theories of sociocultural perspective encumbered in a transitional context; Sino-foreign (SF) graduates to other workplace communities. Without common interests of social interaction, co-participation, and transformation, SFEC are often discredited due to various factors. The learning aims will feature participative and transformative themes that feature qualitative and interpretive methods. Thus, this research involves interviewing four relevant participants from the likes of two Chinese nationals and two non-Chinese, and how they view learning in SFEC applied to a transitional context, the workplace. My furtherance of analysis will generally stress learning, co-participation and transformative learning in activities that circumvents discriminatory elements of artifacts, identity profiling, relationships, commitment and workplace employment for the necessary transition. In the initial research phase, it did seem that putting learning into community practice in China was essential. In the closing stages, thoughts will flow to the legitimisation of participative and transformative learning, which forms the backdrop of this original theme of research gathered through previous works of similar purview. Prawatt and Floden (1994) remark that knowledge, and the belief that knowledge is the result of social interaction and language usage, and thus is a shared, rather than an individual, experience. Presumably, my chosen theories frame the interactive and shared communal nature of the Chinese society and learning systems.

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