| 1. |
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| 2. |
- Ahl, Jonas, et al.
(författare)
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Bacterial aetiology in ventilator-associated pneumonia at a Swedish university hospital
- 2010
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Ingår i: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 1651-1980 .- 0036-5548. ; 42:6-7, s. 469-474
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Tidskriftsartikel (refereegranskat)abstract
- Ventilator-associated pneumonia (VAP) is a common complication of respiratory support and is associated with increased mortality, morbidity and costs, and a prolonged stay in the intensive care unit. Scandinavian data on the aetiology in VAP are lacking. We hereby present a retrospective study on the aetiology of VAP diagnosed by protective specimen brush culture at Malmo University Hospital in relation to early-and late-onset VAP, antibiotic treatment and the incidence of drug-resistant bacteria. Patients registered with a diagnosis of VAP between January 2004 and September 2007 were included in the study. Sixty-five of 109 patients diagnosed with VAP met the inclusion criteria, and 103 bacterial isolates were cultured from these patients. The most common findings among the 65 VAP episodes were Enterobacteriaceae (28), Pseudomonas aeruginosa (13), Haemophilus influenzae (12) and Staphylococcus aureus (8). Patients with no antibiotic treatment at the onset of VAP had significantly more H. influenzae (p = 0.035) and Gram-positive pathogenic bacteria (p = 0.019). There was no difference in incidence of P. aeruginosa between early-and late-onset VAP. Resistant bacteria were found in 18% of the patients.
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| 3. |
- Ahlqvist, Emma, et al.
(författare)
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Novel subgroups of adult-onset diabetes and their association with outcomes : a data-driven cluster analysis of six variables
- 2018
-
Ingår i: The Lancet Diabetes and Endocrinology. - 2213-8587 .- 2213-8595. ; 6:5, s. 361-369
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundDiabetes is presently classified into two main forms, type 1 and type 2 diabetes, but type 2 diabetes in particular is highly heterogeneous. A refined classification could provide a powerful tool to individualise treatment regimens and identify individuals with increased risk of complications at diagnosis.MethodsWe did data-driven cluster analysis (k-means and hierarchical clustering) in patients with newly diagnosed diabetes (n=8980) from the Swedish All New Diabetics in Scania cohort. Clusters were based on six variables (glutamate decarboxylase antibodies, age at diagnosis, BMI, HbA1c, and homoeostatic model assessment 2 estimates of β-cell function and insulin resistance), and were related to prospective data from patient records on development of complications and prescription of medication. Replication was done in three independent cohorts: the Scania Diabetes Registry (n=1466), All New Diabetics in Uppsala (n=844), and Diabetes Registry Vaasa (n=3485). Cox regression and logistic regression were used to compare time to medication, time to reaching the treatment goal, and risk of diabetic complications and genetic associations.FindingsWe identified five replicable clusters of patients with diabetes, which had significantly different patient characteristics and risk of diabetic complications. In particular, individuals in cluster 3 (most resistant to insulin) had significantly higher risk of diabetic kidney disease than individuals in clusters 4 and 5, but had been prescribed similar diabetes treatment. Cluster 2 (insulin deficient) had the highest risk of retinopathy. In support of the clustering, genetic associations in the clusters differed from those seen in traditional type 2 diabetes.InterpretationWe stratified patients into five subgroups with differing disease progression and risk of diabetic complications. This new substratification might eventually help to tailor and target early treatment to patients who would benefit most, thereby representing a first step towards precision medicine in diabetes.
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| 4. |
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| 5. |
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| 6. |
- Anderberg, Mats, 1961-, et al.
(författare)
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Mer än varannan ungdom med alkohol- och narkotikaproblem i öppenvården har erfarenhet av utsatthet i barndomen
- 2019
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Ingår i: Socialmedicinsk Tidskrift. - Stockholm : Karolinska Institutet. - 0037-833X. ; 96:6, s. 786-799
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Tidskriftsartikel (refereegranskat)abstract
- Det finns idag få svenska studier som undersöker erfarenheter av utsattheti barndom hos ungdomar med drogproblem, särskilt inom öppenvården.Den här studien analyserade erfarenheter av försummelse och övergreppunder barndomen hos ungdomar (medelålder 18 år) som påbörjat öppenvårdsbehandlingför drogproblem. Resultaten visade att många ungdomarhade erfarenheter av försummelse och övergrepp i barndomen. Erfarenhetav utsatthet i barndomen var också relaterat till upplevda problem i uppväxtfamiljen,t.ex. ekonomiska svårigheter, missbruk, psykisk ohälsa och våld ifamiljen. Resultaten pekar på att det är angeläget att även utreda utsattheti barndomen bland ungdomar i behandling för drogproblem, särskilt då det idag finns god evidens för att psykiatrisk samsjuklighet (t.ex. traumareaktionoch drogproblem) bör behandlads samtidigt för att uppnå bäst effekt.
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| 7. |
- Anderberg, Mats, et al.
(författare)
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Mer än varannan ungdom med alkohol- och narkotikaproblem i öppenvården har erfarenhet av utsatthet i barndomen
- 2019
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Ingår i: Socialmedicinsk Tidskrift. - 0037-833X. ; 96:6, s. 786-799
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Tidskriftsartikel (refereegranskat)abstract
- Few Swedish studies investigated experiences of childhood maltreatment in adolescents with substance use problems, especially in outpatient care. This study analyzed experiences of neglect and abuse during childhood in adol- escents (mean age 18 years) who started outpatient treatment for substance use problems. The results showed that several of them had experience of child maltreatment. Child maltreatment was also related to perceived pro- blems in the upbringing family, e.g. financial difficulties, substance use pro- blems, mental illness and violence in the family. This indicate the importance to investigate experiences of child maltreatment among adolescents in tre- atment for substance use problems, especially since there is evidence to- day that psychiatric co-morbidity (e.g. trauma reaction and drug problems) should be treated simultaneously to achieve the best effect.
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| 8. |
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| 9. |
- Baldanzi, Gabriel, et al.
(författare)
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Accelerometer-based physical activity is associated with the gut microbiota in 8416 individuals in SCAPIS.
- 2024
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Ingår i: EBioMedicine. - : Elsevier. - 2352-3964. ; 100
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Previous population-based studies investigating the relationship between physical activity and the gut microbiota have relied on self-reported activity, prone to reporting bias. Here, we investigated the associations of accelerometer-based sedentary (SED), moderate-intensity (MPA), and vigorous-intensity (VPA) physical activity with the gut microbiota using cross-sectional data from the Swedish CArdioPulmonary bioImage Study.METHODS: In 8416 participants aged 50-65, time in SED, MPA, and VPA were estimated with hip-worn accelerometer. Gut microbiota was profiled using shotgun metagenomics of faecal samples. We applied multivariable regression models, adjusting for sociodemographic, lifestyle, and technical covariates, and accounted for multiple testing.FINDINGS: Overall, associations between time in SED and microbiota species abundance were in opposite direction to those for MPA or VPA. For example, MPA was associated with lower, while SED with higher abundance of Escherichia coli. MPA and VPA were associated with higher abundance of the butyrate-producers Faecalibacterium prausnitzii and Roseburia spp. We observed discrepancies between specific VPA and MPA associations, such as a positive association between MPA and Prevotella copri, while no association was detected for VPA. Additionally, SED, MPA and VPA were associated with the functional potential of the microbiome. For instance, MPA was associated with higher capacity for acetate synthesis and SED with lower carbohydrate degradation capacity.INTERPRETATION: Our findings suggest that sedentary and physical activity are associated with a similar set of gut microbiota species but in opposite directions. Furthermore, the intensity of physical activity may have specific effects on certain gut microbiota species.FUNDING: European Research Council, Swedish Heart-Lung Foundation, Swedish Research Council, Knut and Alice Wallenberg Foundation.
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| 10. |
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| 11. |
- Björkman, Mats, et al.
(författare)
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Impact of the Ethernet capture effect on bandwidth measurements
- 2000
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Ingår i: NETWORKING 2000. - 0302-9743. ; 1815, s. 156-167
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we present impacts of the Ethernet capture effect on bandwidth measurements. We show that the unfairness caused by the Ethernet capture effect can have a severe impact on the ability to estimate available bandwidth. We define two metrics, su
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| 12. |
- Boson, Karin, 1984, et al.
(författare)
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Adolescents with substance use problems in outpatient treatment: a one-year prospective follow-up study focusing on mental health and gender differences
- 2022
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Ingår i: Substance Abuse Treatment, Prevention, and Policy. - : Springer Science and Business Media LLC. - 1747-597X. ; 17:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Although several studies have found a high incidence of coexisting mental health problems among adolescents with substance use problems, follow-up studies addressing how these conditions change over time are rare. The study will describe and analyze indications of mental health problems and how various risk factors predict outcomes 1 year after initial treatment contact. In addition, gender-specific risk factors are explored. Methods A clinical sample of 455 adolescents (29% girls, median age 17 years) answered a structural interview at baseline and were followed up using official records 1 year after initiated treatment. Bivariate associations and logistic regressions were conducted to analyse the links between risk factors at the individual, social, and structural levels as well as links between various mental illness symptoms at treatment start and indications of mental health problems 1 year later were analysed. Results The results show that mental health problems among adolescents largely persisted 1 year after start of outpatient care for substance use problems. Forty-two per cent of the sample displayed indications of mental health problems at follow-up, and registrations for both outpatient treatment and psychiatric medication were more common among the girls. Girls also reported more mental illness symptoms at treatment start than boys did, especially anxiety. Depression and suicidal thoughts had predictive values regarding indications of mental health problems and small cumulative effects were found for 6-10 co-occurring risk factors. Conclusions Adolescents with depression and suicidal thoughts at treatment start should yield attention among clinicians as these general risk factors could predict indication of mental health problems at 1 year follow-up effectively. Also, patients with more than six co-occurring risk factors seem more vulnerable for continued mental health problems. Generally, girls displayed a greater mental health and psychosocial burden at treatment initiation and were more likely to show indication of mental health problems at follow-up. These results suggests that girls are more likely to get psychiatric out-treatment parallel to, or after, substance abuse treatment. We recommend further investigation of gender differences and gender-specific needs in substance use treatment.
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| 13. |
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| 14. |
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| 15. |
- Ekelin, Svante, et al.
(författare)
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Real-Time Measurement of End-to-End Available Bandwidth using Kalman Filtering
- 2006
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Ingår i: 10th IEEE/IFIP Network Operations and Management Symposium, 2006. NOMS 2006.. - Piscataway, New Jersey, USA : IEEE Computer Society. - 1424401429 - 9781424401420 ; , s. 73-84
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Konferensbidrag (refereegranskat)abstract
- This paper presents a new method, BART (bandwidth available in real-time), for estimating the end-to-end available bandwidth over a network path. It estimates bandwidth quasi-continuously, in real-time. The method has also been implemented as a tool. It relies on self-induced congestion, and repeatedly samples the available bandwidth of the network path with sequences of probe packet pairs, sent at randomized rates. BART requires little computation in each iteration, is lightweight with respect to memory requirements, and adds only a small amount of probe traffic. The BART method uses Kalman filtering, which enables real-time estimation (a.k.a. tracking). It maintains a current estimate, which is incrementally improved with each new measurement of the inter-packet time separations in a sequence of probe packet pairs. The measurement model has a strong non-linearity, and would not at first sight be considered suitable for Kalman filtering, but we show how this non-linearity can be handled. BART may be tuned according to the specific needs of the measurement application, such as agility vs. stability of the estimate. We have tested an implementation of BART in a physical test network with carefully controlled cross traffic, with good accuracy and agreement. Test measurements have also been performed over the Internet. We compare the performance of BART with that of pathChirp, a state-of-the-art tool for measuring end-to-end available bandwidth in real-time
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| 16. |
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| 17. |
- Ekelin, Svante, et al.
(författare)
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Real-time measurement of end-to-end available bandwidth using Kalman filtering
- 2006. - 1
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Konferensbidrag (refereegranskat)abstract
- This paper presents a new method, BART (Bandwidth Available in Real-Time), for estimating the end-to-end available bandwidth over a network path. It estimates bandwidth quasi-continuously, in real-time. The method has also been implemented as a tool. It relies on self-induced congestion, and probes the network path with trains of probe packets, sent at randomized rates. BART requires little computation in each iteration, is light-weight with respect to memory requirements, and adds only a small amount of probe traffic. The BART method is based on Kalman filtering, which enables real-time estimation (a.k.a. tracking) with optimum performance under general conditions. It maintains a current estimate, which is incrementally improved with each new measurement of the inter-packet time separations in a probe packet train. The measurement model has a strong non-linearity, and would not at first sight be considered suitable for Kalman filtering, but we show how this non-linearity can be handled. BART may be tuned according to the specific needs of the measurement application, such as agility vs. stability of the estimate, and the desired time-scale on which to track traffic fluctuations. We have tested BART in a physical test network with carefully controlled cross traffic, with good accuracy and agreement. Test measurements have also been performed over the Internet. We compare the performance of BART with that of pathChirp, a state-of-the-art tool for measuring end-to-end available bandwidth in real-time.
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| 18. |
- Ekerstad, Niklas, et al.
(författare)
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Clinical Frailty Scale classes are independently associated with 6-month mortality for patients after acute myocardial infarction
- 2022
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Ingår i: European Heart Journal. - : Oxford University Press. - 2048-8726 .- 2048-8734. ; 11:2, s. 89-98
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Data on the prognostic value of frailty to guide clinical decision-making for patients with myocardial infarction (MI) are scarce. To analyse the association between frailty classification, treatment patterns, in-hospital outcomes, and 6-month mortality in a large population of patients with MI.Methods and results: An observational, multicentre study with a retrospective analysis of prospectively collected data using the SWEDEHEART registry. In total, 3381 MI patients with a level of frailty assessed using the Clinical Frailty Scale (CFS-9) were included. Of these patients, 2509 (74.2%) were classified as non-vulnerable non-frail (CFS 1–3), 446 (13.2%) were vulnerable non-frail (CFS 4), and 426 (12.6%) were frail (CFS 5–9). Frailty and non-frail vulnerability were associated with worse in-hospital outcomes compared with non-frailty, i.e. higher rates of mortality (13.4% vs. 4.0% vs. 1.8%), cardiogenic shock (4.7% vs. 2.5% vs. 1.9%), and major bleeding (4.5% vs. 2.7% vs. 1.1%) (allP < 0.001), and less frequent use of evidence-based therapies. In Cox regression analyses, frailty was strongly and independently associated with 6-month mortality compared with non-frailty, after adjustment for age, sex, the GRACE risk score components, and other potential risk factors [hazard ratio (HR) 3.32, 95% confidence interval (CI) 2.30–4.79]. A similar pattern was seen for vulnerable non-frail patients (fully adjusted HR 2.07, 95% CI1.41–3.02).Conclusion: Frailty assessed with the CFS was independently and strongly associated with all-cause 6-month mortality, also after comprehensive adjustment for baseline differences in other risk factors. Similarly, non-frail vulnerability was independently associated with higher mortality compared with those with preserved functional ability.
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| 19. |
- Engström, Gunnar, et al.
(författare)
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The Swedish CArdioPulmonary BioImage Study : objectives and design
- 2015
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 278:6, s. 645-659
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Tidskriftsartikel (refereegranskat)abstract
- Cardiopulmonary diseases are major causes of death worldwide, but currently recommended strategies for diagnosis and prevention may be outdated because of recent changes in risk factor patterns. The Swedish CArdioPulmonarybioImage Study (SCAPIS) combines the use of new imaging technologies, advances in large-scale 'omics' and epidemiological analyses to extensively characterize a Swedish cohort of 30 000 men and women aged between 50 and 64 years. The information obtained will be used to improve risk prediction of cardiopulmonary diseases and optimize the ability to study disease mechanisms. A comprehensive pilot study in 1111 individuals, which was completed in 2012, demonstrated the feasibility and financial and ethical consequences of SCAPIS. Recruitment to the national, multicentre study has recently started.
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| 20. |
- Enhörning, Sofia, et al.
(författare)
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Seasonal variation of vasopressin and its relevance for the winter peak of cardiometabolic disease : A pooled analysis of five cohorts
- 2022
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 292:2, s. 365-376
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Tidskriftsartikel (refereegranskat)abstract
- Background: Vasopressin concentration is typically higher at night, during stress, and in males, but readily lowered by water intake. Vasopressin is also a causal candidate for cardiometabolic disease, which shows seasonal variation. Objective: To study whether vasopressin concentration varies by season in a temperate climate. Methods: The vasopressin surrogate marker copeptin was analyzed in fasting plasma samples from five population-based cohorts in Malmö, Sweden (n = 25,907, 50.4% women, age 18–86 years). We investigated seasonal variation of copeptin concentration and adjusted for confounders in sinusoidal models. Results: The predicted median copeptin level was 5.81 pmol/L (7.18 pmol/L for men and 4.44 pmol/L for women). Copeptin exhibited a distinct seasonal pattern with a peak in winter (mid-February to mid-March) and nadir in late summer (mid-August to mid-September). The adjusted absolute seasonal variation in median copeptin was 0.62 pmol/L (95% confidence interval [CI] 0.50; 0.74, 0.98 pmol/L [95% CI 0.73; 1.23] for men and 0.46 pmol/L [95% CI 0.33; 0.59] for women). The adjusted relative seasonal variation in mean log copeptin z-score was 0.20 (95% CI 0.17; 0.24, 0.18 [95% CI 0.14; 0.23] in men and 0.24 [95% CI 0.19; 0.29] in women). The observed seasonal variation of copeptin corresponded to a risk increase of 4% for incident diabetes mellitus and 2% for incident coronary artery disease. Conclusion: The seasonal variation of the vasopressin marker copeptin corresponds to increased disease risk and mirrors the known variation in cardiometabolic status across the year. Moderately increased water intake might mitigate the winter peak of cardiometabolic disease.
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| 21. |
- Fred, Mats, et al.
(författare)
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Etnografiska studier av praktiker
- 2022
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Ingår i: Perspektiv på offentlig förvaltning : Teori i praktiken - Teori i praktiken. - 9789144153247 ; , s. 103-126
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- När vi i detta kapitel tar oss an det etnografiska och praktik-baserade studiet av offentlig förvaltning ser vi det inte som enspecifik teori eller metod, utan som ett vetenskapligt förhållningssätt.Denna begreppsliga vaghet, menar vi, speglar en svårighetatt skilja mellan teori och metod – en svårighet som är särskiltframträdande i etnografiska studier. Från ett mer traditionelltstatsvetenskapligt synsätt framstår etnografin i huvudsak somen metod, men som vi kommer att visa så finns det gemensammateoretiska antaganden i de former av etnografiska studier som vihär diskuterar.
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| 22. |
- Fridén, Michael, et al.
(författare)
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Effects of a low-carbohydrate high polyunsaturated fat diet or a healthy Nordic diet versus usual care on liver fat content and cardiometabolic risk factors in people with type 2 diabetes and prediabetes: a randomized controlled trial (NAFLDiet)
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background: Previous trials have shown that plant-derived polyunsaturated fatty acids (PUFA) in place of saturated fat reduces liver fat, a prerequisite for non-alcoholic fatty liver disease (NAFLD). The effect on liver fat from a novel “anti-lipogenic diet” replacing carbohydrates with PUFA or a healthy Nordic diet (HND) higher in whole-grains but lower in saturated fat has not yet been examined. Objectives: To investigate the effects on changes in liver fat (primary outcome) and other cardiometabolic risk factors after 12 months of follow-up in individuals with prediabetes or T2D from three different diet comparisons: a low carbohydrate high PUFA (LCPUFA) diet versus a HND, a LCPUFA diet versus usual care (UC) and a HND versus UC. Methods: A three-arm parallel ad libitum randomized trial was conducted. Adult men and women (n=148) were randomized to one of the three diet groups. Participants in all groups received key food items on a monthly/bimonthly basis. Liver fat and cardiometabolic risk factors were assessed at baseline and after 12 months. Dietary adherence was assessed using weighed food diaries and objective biomarkers. General linear models were employed to estimate the intention-to-treat (ITT) effect. Results: Dietary adherence was high for all diet groups. Liver fat was reduced to a similar extent in the LCPUFA and the HND group compared to UC (-1.46% (95% CI: -2.42, -0.51)) and -1.76 % (95% CI: -2.96, -0.57), respectively. No difference in liver fat between LCPUFA and HND was observed. Body weight and HbA1c decreased more in the HND compared to the other diet groups whereas no differences were observed between LCPUFA and UC. Similar reductions in LDL-cholesterol were observed for the HND and the LCPUFA group compared to UC, but only the HND reduced triglycerides and C-reactive protein (CRP) compared with UC. No differences were observed for any other secondary outcomes.Conclusions: A LCPUFA diet and a HND both reduced liver fat as compared with UC. Given the sustained weight loss after the HND compared to the other groups, together with improvements in other cardiometabolic markers, the HND in particular seems to be useful for the treatment of T2D and NAFLD.
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| 23. |
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| 24. |
- Hogberg, L, et al.
(författare)
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Penicillin-resistant pneumococci in Sweden 1997-2003: Increased multiresistance despite stable prevalence and decreased antibiotic use
- 2006
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Ingår i: Microbial Drug Resistance. - : Mary Ann Liebert Inc. - 1076-6294 .- 1931-8448. ; 12:1, s. 16-22
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Tidskriftsartikel (refereegranskat)abstract
- Antimicrobial resistance patterns and capsular groups of penicillin-resistant Streptococcus pneumoniae (PRP; MIC penicillin G >= 0.5 mg/ml) in Sweden between 1997 and 2003 were described, and trends in resistance and antibiotic sales during the same period were compared. The most common serogroups were in descending order 9, 19, 14, 23, and 6. Despite a low and stable annual PRP rate (proportion of PRP out of all pneumococci) of around 2% during the study period, the proportion of PRP resistant to other antibiotics increased. Of all tested PRP isolates, 82% were also resistant to trimethoprim/sulfamethoxazole, 32% had additional resistance to tetracycline, and 26% to erythromycin. Antibiotic sales figures for all studied antibiotic subgroups decreased during the same period. Little correlation was found between antibiotic sales and PRP resistance rates, indicating that there are still other poorly defined factors contributing to the reported resistance levels in the population. However, although PRP strains in Sweden are becoming more commonly resistant to antibiotics other than beta-lactams, the low and further reduced antibiotic sales still might have delayed the development and rapid spread of PRP in the population.
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| 25. |
- Johnsson, Andreas, et al.
(författare)
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An Analysis of Active End-to-end Bandwidth Measurement Methods in Wireless Networks
- 2006
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Ingår i: E2EMON 06: 4th IEEE/IFIP Workshop on End-to-End Monitoring Techniques and Services: REAL-TIME MONITORING OF INTERNET PATHS. - 9781424401451 ; , s. 75-82
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- For active, probing-based bandwidth measurements performed on top of the unifying IP layer, it may seem reasonable to expect the measurement problem in wireless networks to be no different than the one in wired networks. However, in networks with 802.11 wireless bottleneck links we show that this is not the case. The results from the experiments presented in this paper show that the measured available bandwidth is dependent on the probe packet size (contrary to what is observed in wired networks). Another equally important finding is that the measured link capacity, using the well known TOPP model, is dependent on the probe packet size and on the cross-traffic intensity. The underlying reasons for the observed differences are analyzed by incorporating the characteristics of 802.11 wireless networks into the TOPP model. The extended model is applicable to other end-to-end bandwidth measurement methods as well, such as BART, Pathload and PTR.
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| 26. |
- Johnsson, Andreas, et al.
(författare)
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Bandwidth measurement in wireless networks
- 2006
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Ingår i: IFIP International Federation for Information Processing. - Boston, MA : Springer US. - 0387311718 - 9780387311715 ; , s. 89-98
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Konferensbidrag (refereegranskat)abstract
- For active, probing-based bandwidth measurements performed on top of the unifying IP layer, it may seem reasonable to expect the measurement problem in wireless networks, such as ad-hoc networks, to be no different than the one in wired networks. However, in networks with 802.11 wireless links we show that this is not the case. Our experiments show that the measured available bandwidth is dependent on the probe packet size (contrary to what is observed in wired networks). Another equally important finding is that the measured link capacity is dependent on the probe packet size and on the cross-traffic intensity. The study we present has been performed using a bandwidth measurement tool, DietTopp, that is based on the previously not implemented TOPP method. DietTopp measures the end-to-end available bandwidth of a network path along with the capacity of the congested link.
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| 27. |
- Johnsson, Andreas, 1977-
(författare)
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Modeling, Implementation and Evaluation of IP Network Bandwidth Measurement Methods
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Internet has gained much popularity among the public since the mid 1990's and is now an integrated part of our society. A large range of high-speedbroadband providers and the development of new and more efficient Internet applications increase the possibilities to watch movies and live TV, use IP-telephony and share files over the Internet. Such applications demand high data transmission rates, which in turn consume network bandwidth. Since several users must share the common bandwidth capacity on the Internet, there will be locations in the network where the demand is higher than the capacity. This causes network congestion, which has negative impact on both the data transmission rate and transmission quality.This thesis is about methods for measuring the available bandwidth of a network path between two computers. The available bandwidth can be interpreted as the maximum transfer rate possible without causing congestion. By deploying the methods studied in this thesis the available bandwidth can be measured without previous knowledge of the network topology. When an estimate of the available bandwidth is obtained, the transfer rate when sending messages between computers can be set to the measured value in order to avoid congestion.In the thesis an active end-to-end available bandwidth measurement method called "Bandwidth Available in Real Time" (BART for short) is evaluated. BART measures the available bandwidth by injecting probe packets into the network at a given rate and then analysing how this rate has changed on the receiving side. A Kalman filter is used to update the current estimate of the available bandwidth using the new measurement sample.The focus of the thesis is on how methods, such as BART, function in wireless 802.11 networks, which are very popular in work as well as in home environments. Wireless networks have a different construction compared to many other types of networks and this can affect the accuracy of the measurement methods discussed in this thesis. The effects must be analyzed and understood in order to obtain accurate available bandwidth estimates. Since wireless links are often parts of the network path between a sender and a receiver on the Internet, it is important to study how these links affect the estimates of the available bandwidth.
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| 28. |
- Johnsson, Andreas, et al.
(författare)
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On the Analysis of Packet-Train Probing Schemes
- 2004
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- With a better understanding of how probe packets and cross-traffic packets interact with each other, more accurate measurement methods based on active probing can be developed. Several existing measurement methods rely on packet-train probing schemes. In this article, we study and describe the interactions between probe packets and cross-traffic packets. When one packet within a packet train is delayed, the dispersion (i.e. packet separation) of at least two (and possibly more) probe packets will change. Furthermore, the dispersions are not independent, which may bias calculations based on statistical operations. Many methods use dispersion averages, such as the mean, in the calculation of bandwidth estimates and predictions. We describe cross traffic effects on packet trains. The interaction results in mirror, chain and quantifi- cation patterns. Experiments have been performed in a testbed to explore these patterns. In histograms of delay variations for adjacent probe packets, these patterns are manifested as different identifiable signatures. Finally, we also discuss the effect of these patterns on the mean and median operations.
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| 29. |
- Karlsson, Anna-Malin, 1969-, et al.
(författare)
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Hälsolitteracitet och kunskapsbyggande i informationssamhället
- 2018
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Ingår i: Resultatdialog 2018. - Stockholm : Vetenskapsrådet. - 9789173073745 ; , s. 57-59
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Vårdinstitutioner har inte längre monopol på att förmedla medicinsk kunskap. Patienter söker själva information och delar egna erfarenheter – inte mist på Internet. I fall där kunskapsbehovet är akut och komplext kan en kombination av olika kunskapskällor vara det som krävs för att fylla individens behov. Vi har studerat hur föräldrar till barn med medfött hjärtfel tar till sig information.
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| 30. |
- Malmbjer, Anna
(författare)
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Skilda världar : En språkvetenskaplig undersökning av gruppsamtal som undervisnings- och lärandeform inom högre utbildning
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates the group work and group discussions of students. The general aim is to investigate what opportunities and limitations are presented by group discussion as a form of instruction and learning in higher education. An analysis is made of students’ work with the subject matter and the organization of their discussions as multi-party conversations. The material consists of three recorded group discussions between teacher students at the beginning of their studies who carry out identical or nearly identical tasks for the same course. Four different dimensions of the group discussions are analysed: the presuppositions and external conditions of the group discussions; group discussions as a communicative activity type; the content, coherence and topic progressions of the group discussions, and the categorisations and discursive structures in two frequent transepisodic themes. The results show that, even though the conditions for the three conversations are almost identical, the students interpret and carry out the tasks in different ways. To structure the multi-party conversations, the groups use communicative strategies and techniques from activity types that are familiar and similar, like informal conversations, interviews, seminars, lectures, and meetings. However, the choice of a more institutional form of interaction does not automatically result in an institutional approach to the subject. The groups usually apply an informal perspective to the subject matter and use informal language that does not seem to be sufficient in the educational context. The students are primarily focussed on reaching a shared understanding. This means that in most cases the students take an uncritical stance with each other, that is, they engage in what is known as cumulative talk. The results indicate the need for a more assertive participant in the groups in order for the group discussions to function as a learning situation. In order for there to be more critical discussion in group, students must be able to identify a disorienting dilemma that engages them and students must see shared scrutiny and exploration as a means to new knowledge and understanding.
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| 31. |
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| 32. |
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| 33. |
- Melander, Björn, et al.
(författare)
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Försiktighet ändå bäst
- 2006
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Ingår i: Språkvård. - 0038-8440. ; :4, s. 41-43
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 34. |
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| 35. |
- Melander, Björn, 1958-, et al.
(författare)
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Så tar man livet av ett språk
- 2006
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Ingår i: Språkvård: Tidskrift utgiven av svenska språknämnden. - Stockholm : Nämnden för svensk språkvård. - 0038-8440. ; :2, s. 39-42
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 36. |
- Melander, Bob, et al.
(författare)
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Trace-Driven Network Path Emulation
- 2002
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper reports on on-going work where a trace-driven approach to network path emulation is investigated. Time stamped probe packets are sent along a network path whereby a probe packet trace can be generated. It basically contains the send times and the one-way delays/loss indications of the probe packets. Inside the emulator, the probe packet trace is used by a loss model and a delay model. These determine if a packet should be dropped or what the delay of the packet should be. Three loss models and three delay models are evaluated. For non-responsive UDP-based flows, the trace-driven loss and delay models that determine loss and delay based on loss-rates and delay distribution parameters calculated across the probe packet trace using a small gliding window are found to perform best. For adaptive TCP flows, none of the evaluated trace-driven models performs well. Instead, the Bernoulli loss model and an independent average delay model performs best.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
- Melander, Ida, 1991-
(författare)
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Att göra sin röst hörd : Sjukdomsförhandlande diskurser, genrer och berättelser om endometrios
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main purpose of this thesis is to describe how situated health-related meaning-making about endometriosis is accomplished in three different health-related contexts. Health communication is ever relevant; throughout history, people have become ill, thought about their health and, in many cases, sought care. It is also a shifting practice, in the sense that it changes over time. This thesis explores health communication and negotiations of health and illness in three patient-oriented, alternative and new settings: knowledge negotiations in online discussion forums, seeking care through so-called ‘self-referrals’, and multimodal illness narratives.Specifically, meaning-making about endometriosis is explored. Endometriosis is a chronic condition which, despite its high prevalence, is still relatively unknown, both in society at large and in actual healthcare encounters. This makes the disease a good example to highlight texts and interaction as health communication.The thesis combines a discourse analytical and social semiotic framework, which entails a focus on knowledge, power and available resources for communicating about a disease. In the first study, discussion forum threads dealing with endometriosis are analyzed, showing how illness is negotiated by means of personal and particular experiences. In the second study, self-referrals written for specialist care are explored as an emergent genre, specifically highlighting the resources used to argue for care, as well as patients’ experiences of seeking care in this way. Finally, the third study analyzes illness narratives on Instagram, showing how illness is narrated on a specific platform, within a specific community.Collectively, the three studies shine a light on different ways of participating in health-related settings, and how this is tied to expertise, personal experience, and patient agency. The thesis also contributes to our understanding of how illness communities are formed: the typical patient emerging is active and knowledgeable, fights for care and endures being questioned by a poor quality healthcare service.
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| 41. |
- Muvumba Sellström, Angela, 1973-
(författare)
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Stronger than Justice : Armed Group Impunity for Sexual Violence
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- What conditions lead to confidence among civil war combatants that they will not face accountability for perpetrating sexual violence? This study investigates the causes of impunity for sexual violence among armed actors. It develops a theoretical framework which identifies three explanations for armed group impunity for sexual violence, namely (1) flawed prohibitions inside an armed group; (2) negligent enforcement by its authorities; and (3) pardons in the form of amnesties during the peace process. Adopting a two-pronged approach, the study first explores the associations between amnesties arising from concluding peace agreements and post-settlement levels of sexual violence in Burundi, the Democratic Republic of Congo, Liberia, Mozambique, Sierra Leone and South Africa. A small-scale, events-based dataset of sexual violence by governments and rebel groups in the first three years after war was constructed. The second and main part of the study is a comparison between two rebel groups in Burundi’s civil war (1994-2008), CNDD-FDD (National Council for the Defence of Democracy-Forces for the Defence of Democracy) and Palipehutu-FNL (Palipehutu-Forces for National Liberation) and their practices of prohibition and punishment of wartime sexual violence, taking into account also the possible influence of amnesties. Based on original data from 19 focus groups of ex-combatants from these rebel organisations, it is found that flawed prohibitions and negligent authorities are the main explanations for armed group impunity. The findings do not support amnesties as a cause of armed group impunity for sexual violence. Moreover, additional findings suggest that accountability for sexual violence is triggered by dependency on civilian support, while impunity is facilitated by an armed group’s ability to secure recruits, material and other resources without the help of local communities.
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| 42. |
- Nilsson, Desirée
(författare)
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In the Shadow of Settlement : Multiple Rebel Groups and Precarious Peace
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- How can durable peace be achieved in the wake of a civil war settlement? Previous quantitative research on this topic has, so far, mainly focused on two parties – the government and the opposition – thereby failing to consider the complexity that may arise in conflicts where the rebel side involves several groups. This dissertation addresses this gap in the study of durable peace. It demonstrates theoretically and empirically that three aspects are of significance for lasting peace: (1) the number of warring parties, (2) the inclusion of rebel groups in peace agreements, and (3) the military strength of the signatories. The study applies a bargaining perspective, where uncertainty about the parties’ capability and resolve serves as a key explanation for why peace prevails or breaks down following a settlement. The empirical analysis is based on a unique set of data covering peace agreements in internal armed conflicts during the post-Cold War period. Employing statistical methods, it is found that, with an increasing number of warring parties, peace is less likely to endure. It is also found that more inclusive deals, contrary to a common view, do not increase the likelihood that peace prevails. However, inclusion can make a difference for some parties, as signatories are more likely to stick to peace than parties outside of an agreement. This suggests that no particular formula, in terms of the number of signatories, is required for peace to last. Peace is also shown to be more fragile if the signatory rebel group is strong rather than weak relative to the government, indicating that military power is of importance. In sum, the present research demonstrates that it is pivotal for our understanding of durable peace to consider the complexities that come with a multiparty setting.
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| 43. |
- Nilsson, Erik D., et al.
(författare)
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Copeptin, a Marker of Vasopressin, Predicts Vascular Dementia but not Alzheimer's Disease
- 2016
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 52:3, s. 1047-1053
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Copeptin is a reliable surrogate marker for the neurohypophyseal hormone vasopressin. Elevated plasma level of copeptin has been associated with cardiovascular and metabolic disease risk.OBJECTIVE: To investigate the association between copeptin and risk of dementia.METHODS: In all, 18,240 individuals from Malmö, Sweden, were examined between 2002 and 2006 (mean age 69.3 years, 69.8% men). Incident cases of dementia until 31 December 2009 were identified by linkage with the Swedish National Patient Register. To validate the dementia diagnoses, medical records as well as laboratory and neuroimaging data were carefully reviewed. Baseline level of copeptin was measured in frozen plasma in: (1) all participants who were diagnosed with dementia during follow-up, (2) a random sample of 5100 individuals of the cohort.RESULTS: During a median follow-up of 4.2 years, there were 374 incident dementia cases (age range 60-83 years at baseline): 120 were classified as Alzheimer's disease (AD), 84 as vascular dementia (VaD), and 102 as mixed dementia. In logistic regressions adjusted for cardiovascular risk factors, baseline level of copeptin predicted incident VaD (Odds ratio (OR) 1.30 per 1 SD increase in log copeptin, 95% CI 1.03-1.64). Copeptin did not predict incidence of all-cause dementia (OR 1.05, 95% CI 0.94-1.18), AD (OR 0.97, 95% CI 0.79-1.18), or mixed dementia (OR 0.85, 95% CI 0.68-1.05).CONCLUSION: Elevated plasma level of copeptin is a risk marker for incident VaD, but not for incident AD. This suggests that the vasopressin hormonal system might be involved in the development of VaD.
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| 44. |
- Nordfjall, Katarina, et al.
(författare)
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Telomere Length Is Associated With Obesity Parameters but With a Gender Difference
- 2008
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Ingår i: Obesity. - : Wiley. - 1930-739X .- 1930-7381. ; 16:12, s. 2682-2689
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Tidskriftsartikel (refereegranskat)abstract
- Cardiovascular disease (CVD) and obesity have been coupled to short telomere length in peripheral blood. The biological background to this observation is not obvious from the literature. In this study we have analyzed a large set of known risk factors for CVD in relation to telomere length in blood cells on a merged cohort of 989 individuals recruited in the Malmo Diet and Cancer Cohort (MDCC) and the Northern Sweden MONICA project. We found a significant or borderline association between obesity parameters and telomere length in women after age and center adjustments (BMI: r = -0.106, P = 0.021, weight: r = -0.087, P = 0.060, waist circumference: r = -0.099, P = 0.032, hip circumference: r = -0.128, P = 0.005). In men, a positive borderline correlation to high-density lipoprotein (HDL) (r = 0.111, P = 0.053) and a negative correlation to 2-h post-oral glucose-tolerance test (OGTT) was observed (r = -0.202, P = 0.045). In neither group any association was found between telomere length and cholesterol, serum triglycerides, serum low-density lipoprotein, plasma insulin, blood pressure, pulse pressure, or smoking habits. Our data indicate that telomere length is associated with an "obesity-phenotype" but only in women.
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| 45. |
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| 46. |
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| 47. |
- Randelius, Mats, et al.
(författare)
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Experimental Testing and Computer Simulations of Ductile Fracture in Tool Steels
- 2012
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Ingår i: Steel Research International. - : Wiley-Blackwell. - 1611-3683 .- 1869-344X. ; 83:1, s. 91-99
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Tidskriftsartikel (refereegranskat)abstract
- Ductility was determined in experimental four-point bending tests of smooth specimens of tool steel. The tool steels had different contents of carbides and carbide sizes and with a hardness of approximately 60HRc. Two of the materials tested were produced powder metallurgically, one was spray formed and one was conventionally uphill ingot cast. Carbide size distribution analysis was performed on planar polished sections of each material. Correlation between carbide microstructure and ductility performance was obtained. The fracture mechanisms were investigated with fractography. A 3D FE-model was used to simulate the four-point bending tests and thereby analyse the matrix flow curve. Also the strain at failure was analysed for each material when simulations were performed based on experimental data. SEM-images of the materials carbide microstructure were used to create 2D FE-models. The models simulated crack initiation and propagation by removing elements in the steel matrix as the plastic strain reached a critical level. With three variants, simulations of crack initiation and propagation at carbides were investigated. That was carbides with no cohesion to matrix, carbides fixed to the matrix and carbides with internal cracks. Comparison of strains at failure for the 2D and the 3D FE-models showed good correlation.
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| 48. |
- Randelius, Mats, et al.
(författare)
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Fatigue Strength of Conventionally Cast Tool Steels and its Dependence of Carbide Microstructure
- 2012
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Ingår i: Steel Research International. - : Wiley-Blackwell. - 1611-3683 .- 1869-344X. ; 83:1, s. 83-90
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Tidskriftsartikel (refereegranskat)abstract
- The axial fatigue strength at two million cycles was experimentally determined for two conventionally cast tool steels and successfully compared with results from a fatigue limit model. Specimens were tested both in the rolling and transverse direction and showed large differences in fatigue properties due to the segregated carbide microstructure. Rolling direction specimens experienced higher fatigue strength than the transverse direction specimens. This is due to smaller carbides present in the load affected cross section of the rolling direction fatigue test bars compared to the cross section of the transverse direction fatigue test bars. Fractographic analysis of failed specimens showed that large carbides had caused fatigue failure, which was also predicted by the model. Measured size distributions of carbides and inclusions were used as input data in the model. The probability that at least one particle will be present in the material volume having a size larger than the threshold value for crack propagation was calculated.
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| 49. |
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| 50. |
- Risberg, Jonas, 1968-
(författare)
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Kunskap i interaktion på en nyhetsredaktion : Om kollegiala möten i den redaktionella vardagen
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study examines collaborative work between colleagues in the newsroom of local radio stations. Through the framework of ethnomethodology and conversation analysis the overall aim is to explore how backstage work in the newsroom is initiated, established, and negotiated as a collective knowledge-based practice.Based on video ethnographic fieldwork in five local radio stations, the analyses demonstrate how the newsroom is constituted as a collegial knowledge-based practice through the ways in which colleagues contribute to the accomplishment of seemingly individual tasks in the production of news, and through encounters where journalists request assistance from colleagues to carry out work assignments that are typically technical/practical in their character. The analyses highlight the participants’ epistemic orientations as an interactional engine, but emphasize how this orientation is made relevant for professional actions. Examining in detail how members orient to epistemic asymmetries when requesting assistance in individual tasks, it is shown how accounts expressed in those situations are often double barreled in that they also explicate if the current situation is to be met with instructions or a division of labour. When examining the interactional sequences that ensue in response to requests for help, it is shown how those situations can be understood as communicative pedagogical projects, how the tutor in situ must decompose the overall task into relevant steps and formulate these composite actions so they can be recognized and performed by the colleague. It is also shown how embodied action or absence of expected embodied action is treated as expressions of knowledge, that is, epistemic stance.In these everyday pedagogical practices, the participants establish a local rationality and a situation where two professional colleagues interact. The study thus demonstrates how interaction with colleagues contributes to institutional tasks as well as to the development of different professional skills. In highlighting collaborative work between colleagues in newsrooms the study contributes to the field of epistemics in social interaction, collegial work, talk in institutions, and newsroom ethnographies.
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