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Computer Modeling in Engineering & Sciences 2019年第4期119卷 35-62页

作者： andrew lundberg Pengtao Sun Cheng Wang Chen-song Zhang Department of Mathematical Sciences University of NevadaLas Vegas4505 Maryland ParkwayLas VegasNV 89154USA School of Mathematical Sciences Tongji UniversityShanghaiChina LSEC&NCMIS Academy of Mathematics and System ScienceBeijingChina

The distributed Lagrange multiplier/fictitious domain(DLM/FD)-mixed finite element method is developed and analyzed in this paper for a transient Stokes interface problem with jump *** semi-and fully discrete DLM/FD-mixed finite element scheme are developed for the first time for this problem with a moving interface,where the arbitrary Lagrangian-Eulerian(ALE)technique is employed to deal with the moving and immersed *** and optimal convergence properties are obtained for both *** experiments are carried out for different scenarios of jump coefficients,and all theoretical results are validated.

关键词： Transient Stokes interface problem jump coefficients distributed Lagrange multiplier fictitious domain method mixed finite element an optimal error estimate stability

Psychiatric comorbidities in epilepsy:population co-occurrence,genetic correlations and causal effects

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General Psychiatry 2024年第1期37卷 103-111页

作者： Viktor H Ahlqvist Christina Dardani Paul Madley-Dowd Harriet Forbes Jessica Rast Caichen Zhong Renee M Gardner Christina Dalman Kristen Lyal cRAIG Newschaffer Torbjorn Tomson Michael lundberg Daniel Berglind Neil M Davies Brian K Lee Cecilia Magnusson Dheeraj Rai Department of Global Public Health Karolinska InstitutetStockholmSweden Medical Research Council Integrative Epidemiology Unit Bristol Medical SchoolUniversity of BristolBristolUK Centre for Academic Mental Health Population Health SciencesBristol Medical SchoolUniversity of BristolBristolUK Faculty of Epidemiology and Population Health London School of Hygiene and Tropical MedicineLondonUK A.J.Drexel Autism Institute Drexel UniversityPhiladelphiaPAUSA Department of Epidemiology and Biostatistics School of Public HealthDrexel UniversityPhiladelphiaPAUSA College of Health and Human Development Pennsylvania State UniversityState CollegePAUSA Department of Clinical Neuroscience Karolinska InstitutetStockholmSweden Centre for Epidemiology and Community Medicine Region StockholmStockholmSweden K.G Jebsen Center for Genetic Epidemiology Department of Public Health and NursingNorwegian University of Science and TechnologyTrondheimNorway Division of Psychiatry University Collge LondonLondonUK Department of Statistical Sciences University Cllge LondonLondonK NIHR Biomedical Research Centre University of BristoBristolUK Avon and Wiltshire Partnership NHS Mental Health TrustBristolUK

Background Psychiatric comorbidities are common in patients with *** for the co-occurrence of psychiatric conditions and epilepsy remain poorly *** We aimed to triangulate the relationship between epilepsy and psychiatric conditions to determine the extent and possible origins of these *** Using nationwide Swedish health registries,we quantified the lifetime prevalence of psychiatric disorders in patients with *** then used summarydata from genome-wide association studies to investigate whether the identified observational associations could be attributed to a shared underlying genetic aetiology using cross-trait linkage disequilibrium score ***,we assessed the potential bidirectional relationships using two-sample Mendelian *** In a cohort of 7628495 individuals,we found that almost half of the 94435 individuals diagnosed with epilepsy were also diagnosed with a psychiatric condition in their lifetime(adjusted lifetime prevalence,44.09%;95%confidence interval(Cl)43.78%to 44.39%).We found evidence for a genetic correlation between epilepsy and some neurodevelopmental and psychiatric *** example,we observed a genetic correlation between epilepsy and attention-deficit/hyperactivity disorder(r,=0.18,95%Cl 0.09 to 0.27,p<0.001)—a correlation that was more pronounced in focal epilepsy(r=0.23,95%CI 0.09 to 0.36,p<0.001).Findings from Mendelian randomisation using common genetic variants did not support bidirectional effects between epilepsy and neurodevelopmental or psychiatric *** Psychiatric comorbidities are common in patients with *** correlations may partially explain some comorbidities;however,there is little evidence of a bidirectional relationship between the genetic liability of epilepsy and psychiatric *** findings highlight the need to understand the role of environmental factors or rare genetic variations in the origins of psy

关键词： epilepsy Psychiat lifetime

Deformation,fragmentation and acceleration of a controlled fragmentation charge casing

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Defence Technology（防务技术） 2019年第5期15卷 786-795页

作者： Andreas Helte Olof Andersson Patrik lundberg FOI Defence and SecuritySystems and Technology

Two different finite element software,LS-DYNA and Impetus,have been evaluated to test their ability to predict the deformation,fragmentation and acceleration of a controlled fragmentation charge *** general-purpose program LS-DYNA was used with a multi-material ALE formulation and a masspreserving erosion criterion coupled to a Johnson-Cook fracture *** the Impetus simulations,a third order Lagrangian element formulation was used for the casing and a node-splitting element erosion treatment coupled to a Cockcroft-Latham failure criterion was used to describe casing *** high-explosive gases were described by a discrete particle *** order to acquire data to validate our computational tools and constitutive models,a series of experiments have been performed using a laboratory charge with an internal grooved *** the test series,the charge geometry was fixed except that the groove depth were varied from very shallow to very deep resulting in different deformation patterns,fracture modes and terminal *** diagnostic tools captured the different stages of the expansion and fragmentation of the casing.A high-speed framing camera depicted the deformation pattern before fragmentation and was used to determine the moment when the casing *** different complementary techniques were used to follow the acceleration of the fragments;a Photon Doppler velocimetry to determine the initial acceleration of the casing,double exposed radiographs to estimate the fragment velocity after break-up and a high-speed video to determine the terminal velocity of the fragment after leaving the *** addition,the fragments were soft recovered in a set of sawdust pit tests and their final shape and weight were measured.A SEM was used to characterise the fracture surfaces and to determine the modus of fracture(tensile or shear failure).Comparisons to experiments show that both software can predict the change in deformation behaviour

关键词： Controlled fragmentation Fracture mechanics LS-DYNA Impetus

Improving Fault Detection in Modified Code-A Study from the Telecommunication Industry

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Journal of Computer Science & Technology 2007年第3期22卷 397-409页

作者： Piotr Tomaszewski Lars lundberg Hkan Grahn School of Engineering Blekinge Institute of Technology SE-372 25 RonnebySweden

Many software systems are developed in a number of consecutive releases. In each release not only new code is added but also existing code is often modified. In this study we show that the modified code can be an important source of faults. Faults are widely recognized as one of the major cost drivers in software projects. Therefore, we look for methods that improve the fault detection in the modified code. We propose and evaluate a number of prediction models that increase the efficiency of fault detection. To build and evaluate our models we use data collected from two large telecommunication systems produced by Ericsson. We evaluate the performance of our models by applying them both to a different release of the system than the one they are built on and to a different system. The performance of our models is compared to the performance of the theoretical best model, a simple model based on size, as well as to analyzing the code in a random order （not using any model）. We find that the use of our models provides a significant improvement over not using any model at all and over using a simple model based on the class size. The gain offered by our models corresponds to 38-57% of the theoretical maximum gain.

关键词： fault prediction metrics testing and debugging

Influence of confining prestress on the transition from interface defeat topenetration in ceramic targets

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Defence Technology（防务技术） 2016年第3期12卷 263-271页

作者： Patrik lundberg RenéRENSTROM Olof ANDERSSON FOI Swedish Defence Research AgencySE-164 90 StockholmSweden

Replica scaled impact experiments with unconfined ceramic targets have shown that the transition velocity,i.e.,the impact velocity at which interface defeat ceases and ceramic penetration occurs,decreased as the length scale increased.A possible explanation of how this scale effect is related to the formation of a cone crack in the ceramic has been presented by the authors in an earlier ***,the influence of confinement and prestress on cone cracking and transition velocity is *** hypothesis is that prestress will suppress the formation and growth of the cone crack by lowering the driving stress.A set of impact experiments has been performed in which the transition velocity for four different levels of prestress has been *** transition velocities as a function of the level of confining prestress is compared to an analytical model for the influence of prestress on the formation and extension of the cone crack in the ceramic *** experiments and model indicate that prestress has a strong influence on the transition from interface defeat to penetration,although the model underestimates the influence of prestress.

关键词： Impact Ceramic Armour Interface defeat Dwell Confinement Prestress

Gene-environment interactions in male reproductive health： special reference to the aryl hydrocarbon receptor signaling pathway

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Asian Journal of Andrology 2014年第1期16卷 89-96页

作者： Leon J S Brokken Yvonne lundberg Giwercman Department of Clinical Sciences Molecular Genetic Reproductive Medicine Lund University MalmO Sweden

Over the last few decades, there have been numerous reports of adverse effects on the reproductive health of wildlife and laboratory animals caused by exposure to endocrine disrupting chemicals （EDCs）. The increasing trends in human male reproductive disorders and the mounting evidence for causative environmental factors have therefore sparked growing interest in the health threat posed to humans by EDCs, which are substances in our food, environment and consumer items that interfere with hormone action, biosynthesis or metabolism, resulting in disrupted tissue homeostasis or reproductive function. The mechanisms of EDCs involve a wide array of actions and pathways. Examples include the estrogenic, androgenic, thyroid and retinoid pathways, in which the EDCs may act directly as agonists or antagonists, or indirectly via other nuclear receptors. Dioxins and dioxin-like EDCs exert their biological and toxicological actions through activation of the aryl hydrocarbon-receptor, which besides inducing transcription of detoxifying enzymes also regulates transcriptional activity of other nuclear receptors. There is increasing evidence that genetic predispositions may modify the susceptibility to adverse effects of toxic chemicals. In this review, potential consequences of hereditary predisposition and EDCs are discussed, with a special focus on the currently available publications on interactions between dioxin and androgen signaling.

关键词： androgen receptor aryl hydrocarbon receptor endocrine disrupter

Running Temperature and Mechanical Stability of Grease as Maintenance Parameters of Railway Bearings

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International Journal of Automation and computing 2010年第2期7卷 160-166页

作者： Jan lundberg Aditya Parida Peter Sderholm Division of Operation and Maintenance Engineering Lule University of Technology

Spherical roller bearings in railway car wheels are critical components whose failure may have catastrophic consequences. The present study aims to analyse the mechanical stability of greases and temperature of bearings as indicators for condition-based bearing maintenance. The performed case study includes nine fully-formulated commercial greases examined in the wheel bearings of five ore cars operated in northern Scandinavia. The studied ore cars travelled a distance of about 300 000 km during a period of three years. Small samples of the greases were taken on eight occasions to test their mechanical stability. In addition, the temperatures of the bearings were continuously recorded. After the test period, the wear, electrical damage, and corrosion of the bearings were examined. One of the findings is that the shear stress of the grease at a certain shear velocity （the certain yieldstress （CEY） value） is a good maintenance indicator and is highly dependent on the grease type. The bearing＇s wear, electrical damage and corrosion also depend on the grease type. However, no oxidation of the greases was identified. The paper also outlines a systematic methodology to determine an overall maintenance indicator for railway roller bearings which is based on the field measurements.

关键词： Maintenance mechanical stability railway roller bearings grease lubrication.

Rectal nitric oxide as biomarker in the treatment of inflammatory bowel disease: Responders versus nonresponders

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World Journal of Gastroenterology 2006年第21期12卷 3386-3392页

作者： Tryggve Ljung Sofie lundberg Mark Varsanyi Catharina Johansson Peter T Schmidt Max Herulf Jon O lundberg Per M Hellstr(o|¨)m Department of Gastroenterology and Hepatology Karolinska University Hospital Site SolnaStockholmSweden Department of Physiology and Pharmacology Karolinska Institutet StockholmSweden

AIM： To explore rectal nitric oxide （NO） as biomarker of treatment response in ulcerative colitis （UC） and Crohn＇s disease （CD）, and examine relationships between rectal NO, mucosal expression of NO synthases （NOS）, and pro-inflammatory cytokines. METHODS： Twenty-two patients with UC and 24 with CD were monitored during steroid treatment. Rectal NO levels were measured and clinical activities were assessed on days 1, 3, 7 and 28. Mucosal presence of NOS and pro-inflammatory cytokines were analyzed by immunohistochemistry and RT-PCR. RESULTS： Active UC and CD displayed markedly increased rectal NO levels （10950 ± 7610 and 5 040 ± 1 280 parts per billion （ppb）, respectively） as compared with the controls （154 ± 71 ppb, P 〈 0.001）. Rectal NO correlated weakly with disease activity in both UC and CD （r = 0.34 for UC and r = 0.48 for CD, P 〈 0.01）. In 12 patients, a steroid-refractory course led to colectomy. These patients had only slightly increased NO levels （UC： 620 ± 270 ppb; CD： 1260 ± 550 ppb） compared to those with a therapeutic response （UC： 18860 ± 530 ppb, P 〈 0.001, CD： 10060 ± 3200 ppb, P 〈 0.05）. CONCLUSION： Rectal NO level is a useful biomarker of treatment response in IBD as low NO levels predicts a poor clinical response to steroid treatment.

关键词： Crohn's disease CytokJnes Nitric oxide Steroids Ulcerative colitis

On the sampling strategies and models for measuring diffusion exchange with a double diffusion encoding sequence

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Magnetic Resonance Letters 2023年第3期3卷 232-247,I0003页

作者： Alfredo Ordinola Shan Cai Peter lundberg Ruiliang Bai Evren Ozarslan Department of Biomedical Engineering(IMT) Link oping UniversityLink opingS-58185Sweden Department of Radiation Physics Department of HealthMedicine and Caring Sciences(HMV)Link oping UniversityLink opingS-58183Sweden Center for Medical Image Science and Visualization(CMIV) Link oping UniversityLink opingS-58185Sweden School of Medicine Zhejiang University866 Yuhangtang RdHangzhou310058China

Water exchange between the different compartments of a heterogeneous specimen can be characterized via diffusion magnetic resonance imaging(dMRI).Many analysis frameworks using dMRI data have been proposed to describe exchange,often using a double diffusion encoding(DDE)stimulated echo *** such as diffusion exchange weighted imaging(DEWI)and the filter exchange and rapid exchange models,use a specific subset of the full space DDE *** this work,a general representation of the DDE signal was employed with different sampling schemes(namely constant b1,diagonal and anti-diagonal)from the data reduction models to estimate exchange.A near-uniform sampling scheme was proposed and compared with the other sampling *** filter exchange and rapid exchange models were also applied to estimate exchange with their own subsampling *** subsampling schemes and models were compared on both simulated data and experimental data acquired with a benchtop MR *** synthetic data,the diagonal and near-uniform sampling schemes performed the best due to the consistency of their estimates with the ground *** experimental data,the shifted diagonal and near-uniform sampling schemes outperformed the others,yielding the most consistent estimates with the full space *** results suggest the feasibility of measuring exchange using a general representation of the DDE signal along with variable sampling *** future studies,algorithms could be further developed for the optimization of sampling schemes,as well as incorporating additional properties,such as geometry and diffusion anisotropy,into exchange frameworks.

关键词： Diffusion MRI Water exchange Sampling schemes Double diffusion encoding

Anti‐Jo1 autoantibodies,fromclinictothebench

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Rheumatology & Autoimmunity 2022年第2期2卷 57-68页

作者： Angeles S.Galindo‐Feria Begum Horuluoglu Ingrid E.lundberg Department of Medicine Division of RheumatologyKarolinska InstitutetKarolinska University HospitalStockholmSweden Center for Molecular Medicine Karolinska InstitutetKarolinska University HospitalStockholmSweden

Introduction:Idiopathic inflammatory myopathies(IIM)also known as myositis,is a chronic autoimmune disease which affects muscles,skin,joints and *** of the most common autoantibodies with a prevalence of 25‐35%,is the anti‐Jo‐1 autoantibodies,targeting the histidyl‐transfer RNA synthetase(HisRS).These autoantibodies are strongly associated with a distinct clinical phenotype called anti‐synthetase syndrome(ASyS)that includes interstitial lung disease(ILD),myositis,arthritis and Raynaud’s *** mechanism of how autoantibodies are produced and how they contribute to disease pathogenesis is *** Covered:In this review we will discuss the clinical manifestations associated with Jo‐1 autoantibodies,and the association with clinical ***,we will also review the molecular characteristics of the antibodies and how they affect the cells of the immune system in order to understand possible disease mechanisms.

关键词： anti‐Jo1 autoantibodies ASyS HisRS IIM myositis