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1.
  • Alfredsson, Joakim, 1962-, et al. (author)
  • Randomized comparison of early supplemental oxygen versus ambient air in patients with confirmed myocardial infarction : Sex-related outcomes from DETO2X-AMI
  • 2021
  • In: American Heart Journal. - : Mosby Inc.. - 0002-8703 .- 1097-6744. ; 237, s. 13-24
  • Journal article (peer-reviewed)abstract
    • Background: The purpose of this study is to investigate the impact of oxygen therapy on cardiovascular outcomes in relation to sex in patients with confirmed myocardial infarction (MI).Methods: The DETermination of the role of Oxygen in suspected Acute Myocardial Infarction trial randomized 6,629 patients to oxygen at 6 L/min for 6-12 hours or ambient air. In the present subgroup analysis including 5,010 patients (1,388 women and 3,622 men) with confirmed MI, we report the effect of supplemental oxygen on the composite of all-cause death, rehospitalization with MI, or heart failure at long-term follow-up, stratified according to sex.Results: Event rate for the composite endpoint was 18.1% in women allocated to oxygen, compared to 21.4% in women allocated to ambient air (hazard ratio [HR] 0.83, 95% confidence interval [CI] 0.65-1.05). In men, the incidence was 13.6% in patients allocated to oxygen compared to 13.3% in patients allocated to ambient air (HR 1.03, 95% CI 0.86-1.23). No significant interaction in relation to sex was found (P=.16). Irrespective of allocated treatment, the composite endpoint occurred more often in women compared to men (19.7 vs 13.4%, HR 1.51; 95% CI, 1.30-1.75). After adjustment for age alone, there was no difference between the sexes (HR 1.06, 95% CI 0.91-1.24), which remained consistent after multivariate adjustment.Conclusion: Oxygen therapy in normoxemic MI patients did not significantly affect all-cause mortality or rehospitalization for MI or heart failure in women or men. The observed worse outcome in women was explained by differences in baseline characteristics, especially age
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2.
  • Brunström, Anna, et al. (author)
  • NEWCOM DR6.2: First report on frameworks/models matching Department 6 needs
  • 2005
  • Reports (peer-reviewed)abstract
    • During the first phase of NEWCOM the focus areas of Department 6 were identified and refined. A number of relevant knowledge gaps were identified for the areas transport protocols, architectures and cross-layer aspects, and modelling. In this deliverable we describe a first set of frameworks/models to support research integration within the Department. The integration approach and the defined models/frameworks are described for each one of the selected knowledge gaps. The deliverable also includes a report on tools, software libraries and traces that can be shared between the partners
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3.
  • Docherty, Anna R, et al. (author)
  • GWAS Meta-Analysis of Suicide Attempt: Identification of 12 Genome-Wide Significant Loci and Implication of Genetic Risks for Specific Health Factors.
  • 2023
  • In: The American journal of psychiatry. - : American Psychiatric Association Publishing. - 1535-7228 .- 0002-953X. ; 180:10, s. 723-738
  • Journal article (peer-reviewed)abstract
    • Suicidal behavior is heritable and is a major cause of death worldwide. Two large-scale genome-wide association studies (GWASs) recently discovered and cross-validated genome-wide significant (GWS) loci for suicide attempt (SA). The present study leveraged the genetic cohorts from both studies to conduct the largest GWAS meta-analysis of SA to date. Multi-ancestry and admixture-specific meta-analyses were conducted within groups of significant African, East Asian, and European ancestry admixtures.This study comprised 22 cohorts, including 43,871 SA cases and 915,025 ancestry-matched controls. Analytical methods across multi-ancestry and individual ancestry admixtures included inverse variance-weighted fixed-effects meta-analyses, followed by gene, gene-set, tissue-set, and drug-target enrichment, as well as summary-data-based Mendelian randomization with brain expression quantitative trait loci data, phenome-wide genetic correlation, and genetic causal proportion analyses.Multi-ancestry and European ancestry admixture GWAS meta-analyses identified 12 risk loci at p values <5×10-8. These loci were mostly intergenic and implicated DRD2, SLC6A9, FURIN, NLGN1, SOX5, PDE4B, and CACNG2. The multi-ancestry SNP-based heritability estimate of SA was 5.7% on the liability scale (SE=0.003, p=5.7×10-80). Significant brain tissue gene expression and drug set enrichment were observed. There was shared genetic variation of SA with attention deficit hyperactivity disorder, smoking, and risk tolerance after conditioning SA on both major depressive disorder and posttraumatic stress disorder. Genetic causal proportion analyses implicated shared genetic risk for specific health factors.This multi-ancestry analysis of suicide attempt identified several loci contributing to risk and establishes significant shared genetic covariation with clinical phenotypes. These findings provide insight into genetic factors associated with suicide attempt across ancestry admixture populations, in veteran and civilian populations, and in attempt versus death.
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4.
  • Hasselström, Nicklas, et al. (author)
  • The Design, Implementation, and Performance Evaluation of Secure Socket SCTP 2.0
  • 2015
  • Reports (other academic/artistic)abstract
    • The Stream Control Transmission Protocol (SCTP) is acomparatively new transport protocol that presents some advanced features compared to other standardized transport protocols. However, there are currently no standardized end-to-end security solutions suited for SCTP. One proposal for end-to-end encryption is the Secure Socket SCTP (S2-SCTP) protocol, developed by researchers at Karlstad University.  The security solution for SCTP described in this report uses key agreement for obtaining keys to be able to provide data confidentiality by encryption. The protocol is based on the S2-SCTP protocol, with smaller changes, and an overlaying management protocol has been designed and implemented. The management protocolis used to enable encryption and TLS authentication, to give a secure communication library over existing Berkeley Sockets. The performance evaluation of S2-SCTP compared to the already standardized end-to-endsecurity solutions, i.e., TLS over SCTP and DTLS over SCTP, shows that S2-SCTP achieves a higher throughput while still maintaining most of the advantages of SCTP.
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5.
  • Mullins, Niamh, et al. (author)
  • Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors
  • 2022
  • In: Biological Psychiatry. - : Elsevier. - 0006-3223 .- 1873-2402. ; 91:3, s. 313-327
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders.METHODS: We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors.RESULTS: Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged.CONCLUSIONS: Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.
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6.
  • Watson, Hunna J., et al. (author)
  • Common Genetic Variation and Age of Onset of Anorexia Nervosa
  • 2022
  • In: BIOLOGICAL PSYCHIATRY: GLOBAL OPEN SCIENCE. - : Elsevier BV. - 2667-1743. ; 2:4, s. 368-378
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: Genetics and biology may influence the age of onset of anorexia nervosa (AN). The aims of this study were to determine whether common genetic variation contributes to age of onset of AN and to investigate the genetic associations between age of onset of AN and age at menarche.METHODS: A secondary analysis of the Psychiatric Genomics Consortium genome-wide association study (GWAS) of AN was performed, which included 9335 cases and 31,981 screened controls, all from European ancestries. We conducted GWASs of age of onset, early-onset AN (,13 years), and typical-onset AN, and genetic correlation, genetic risk score, and Mendelian randomization analyses.RESULTS: Two loci were genome-wide significant in the typical-onset AN GWAS. Heritability estimates (single nucleotide polymorphism-h2) were 0.01-0.04 for age of onset, 0.16-0.25 for early-onset AN, and 0.17-0.25 for typical-onset AN. Early-and typical-onset AN showed distinct genetic correlation patterns with putative risk factors for AN. Specifically, early-onset AN was significantly genetically correlated with younger age at menarche, and typical-onset AN was significantly negatively genetically correlated with anthropometric traits. Genetic risk scores for age of onset and early-onset AN estimated from independent GWASs significantly predicted age of onset. Mendelian randomization analysis suggested a causal link between younger age at menarche and early -onset AN.CONCLUSIONS: Our results provide evidence consistent with a common variant genetic basis for age of onset and implicate biological pathways regulating menarche and reproduction.
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7.
  • Abbas, Muhammad Tahir, et al. (author)
  • Energy-Saving Solutions for Cellular Internet of Things - A Survey
  • 2022
  • In: IEEE Access. - IEEE : IEEE. - 2169-3536. ; 10, s. 62096-62096
  • Journal article (peer-reviewed)abstract
    • The Cellular Internet of Things (CIoT), a new paradigm, paves the way for a large-scale deployment of IoT devices. CIoT promises enhanced coverage and massive deployment of low-cost IoT devices with an expected battery life of up to 10 years. However, such a long battery life can only be achieved provided the CIoT device is configured with energy efficiency in mind. This paper conducts a comprehensive survey on energy-saving solutions in 3GPP-based CIoT networks. In comparison to current studies, the contribution of this paper is the classification and an extensive analysis of existing energy-saving solutions for CIoT, e.g., the configuration of particular parameter values and software modifications of transport- or radio-layer protocols, while also stressing key parameters impacting the energy consumption such as the frequency of data reporting, discontinuous reception cycles (DRX), and Radio Resource Control (RRC) timers. In addition, we discuss shortcomings, limitations, and possible opportunities which can be investigated in the future to reduce the energy consumption of CIoT devices.
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8.
  • Abbas, Muhammed Tahir, et al. (author)
  • Evaluating the Impact of Pre-Configured Uplink Resources in Narrowband IoT
  • 2024
  • In: Sensors. - Switzerland. - 1424-8220. ; 24:17
  • Journal article (peer-reviewed)abstract
    • Deploying Cellular Internet of Things (CIoT) devices in urban and remote areas faces significant energy efficiency challenges. This is especially true for Narrowband IoT (NB-IoT) devices, which are expected to function on a single charge for up to 10 years while transmitting small amounts of data daily. The 3rd Generation Partnership Project (3GPP) has introduced energy-saving mechanisms in Releases 13 to 16, including Early Data Transmission (EDT) and Preconfigured Uplink Resources (PURs). These mechanisms extend battery life and reduce latency by enabling data transmission without an active Radio Resource Control (RRC) connection or Random Access Procedure (RAP). This paper examines these mechanisms using the LENA-NB simulator in the ns-3 environment, which is a comprehensive framework for studying various aspects of NB-IoT. The LENA-NB has been extended with PURs, and our analysis shows that PURs significantly enhance battery life and latency efficiency, particularly in high-density environments. Compared to the default RAP method, PURs reduce energy consumption by more than 2.5 times and increases battery life by 1.6 times. Additionally, PURs achieve latency reductions of 2.5 - 3.5 times. The improvements with PURs are most notable for packets up to 125 bytes. Our findings highlight PURs' potential to enable more efficient and effective CIoT deployments across various scenarios. This study represents a detailed analysis of latency and energy consumption in a simulated environment, advancing the understanding of PURs' benefits.
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9.
  • Abbas, Muhammad Tahir, et al. (author)
  • Guidelines for an Energy Efficient Tuning of the NB-IoT Stack
  • 2020
  • In: 45th IEEE Conference on Local Computer Networks (LCN). - : IEEE Communications Society. ; , s. 60-69
  • Conference paper (peer-reviewed)abstract
    • In this paper, we study the energy consumptionof Narrowband IoT devices. The paper suggests that key tosaving energy for NB-IoT devices is the usage of full Discontinuous Reception (DRX), including the use of connected-mode DRX (cDRX): In some cases, cDRX reduced the energy consumption over a 10-year period with as much as 50%. However, the paper also suggests that tunable parameters, such as the inactivity timer, do have a significant impact. On the basis of our findings, guidelines are provided on how to tune the NB-IoT device so that it meets the target of the 3GPP, i.e., a 5-Wh battery should last for at least 10 years. It is further evident from our results that the energy consumption is largely dependent on the intensity and burstiness of the traffic, and thus could be significantly reduced if data is sent in bursts with less intensity,irrespective of cDRX support.
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10.
  • Abbas, Muhammad Tahir (author)
  • Improving the Energy Efficiency of Cellular IoT Device
  • 2023
  • Licentiate thesis (other academic/artistic)abstract
    • Cellular Internet of Things (CIoT) has emerged as a promising technology to support applications that generate infrequent data. One requirement on these applications, often battery-powered devices, is low energy consumption to enable extended battery life. Narrowband IoT (NB-IoT) is a promising technology for IoT due to its low power consumption, which is essential for devices that need to run on battery power for extended periods. However, the current battery life of NB-IoT devices is only a few years, which is insufficient for many applications. This thesis investigates the impact of energy-saving mechanisms standardized by 3GPP on battery life of NB-IoT devices. The main research objective is to classify and analyze existing energy-saving solutions for CIoT and examine their limitations, to study the impact of standardized energy-saving mechanisms on the battery life of NB-IoT devices, both in isolation and combined, and to provide guidelines on how to configure NB-IoT devices to reduce energy consumption efficiently. The research aims to provide a deeper understanding of the effect of energy-saving mechanisms and best practices to balance energy efficiency and performance of NB-IoT devices. Applying the proposed solutions makes it possible to achieve a battery life of 10~years or more for CIoT devices.
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  • Result 1-10 of 105
Type of publication
journal article (51)
conference paper (42)
reports (5)
licentiate thesis (5)
doctoral thesis (1)
book chapter (1)
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Type of content
peer-reviewed (93)
other academic/artistic (12)
Author/Editor
Alfredsson, Stefan, ... (43)
Brunström, Anna, 196 ... (23)
Erlinge, David (20)
Alfredsson, Joakim (20)
Jernberg, Tomas (19)
Lindahl, Bertil, 195 ... (13)
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Brunstrom, Anna, 196 ... (13)
James, Stefan, 1964- (12)
Alfredsson, Lars (12)
Alay, Özgü (9)
Alfredsson, Joakim, ... (9)
Garcia, Johan, 1970- (9)
Venetsanos, Dimitrio ... (9)
Yndigegn, Troels (9)
James, Stefan K., 19 ... (9)
Herlitz, Johan, 1949 (8)
Grinnemo, Karl-Johan ... (8)
Alfredsson, Stefan (8)
Ravn-Fischer, Annica ... (8)
Mancuso, Vincenzo (8)
Mellia, Marco (8)
Söderberg, Stefan (8)
Rajiullah, Mohammad, ... (7)
Brunström, Anna (7)
Omerovic, Elmir, 196 ... (7)
Lutu, Andra (7)
Hofmann, Robin (7)
Fröbert, Ole, 1964- (6)
Koul, Sasha (6)
Karlsson, Jonas, 197 ... (6)
Swahn, Eva (6)
Omerovic, Elmir (6)
Östlund, Ollie (6)
Abbas, Muhammad Tahi ... (5)
Eklund, Johan, 1966- (5)
Redfors, Björn (5)
Hagström, Emil (5)
Peón-Quirós, Miguel (5)
Hirsch, Thomas (5)
Mikael, Sternad (5)
Engström, Gunnar (4)
Lind, Lars (4)
Sternad, Mikael (4)
Lindberg, Eva (4)
Persson, Jonas (4)
Evensen, Kristian (4)
Ajmone Marsan, Marco (4)
James, Stefan (4)
de Faire, Ulf (4)
Erlinge, D. (4)
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University
Karlstad University (47)
Uppsala University (43)
Karolinska Institutet (38)
Linköping University (31)
Lund University (24)
University of Gothenburg (20)
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Umeå University (10)
Royal Institute of Technology (9)
University of Borås (8)
Örebro University (6)
Jönköping University (3)
Halmstad University (2)
Högskolan Dalarna (2)
Mid Sweden University (1)
The Swedish School of Sport and Health Sciences (1)
RISE (1)
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Language
English (105)
Research subject (UKÄ/SCB)
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Engineering and Technology (38)
Natural sciences (26)
Social Sciences (4)

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