| 1. |
- Abbafati, Cristiana, et al.
(author)
-
- 2020
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Journal article (peer-reviewed)
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| 2. |
- Agardh, Emilie E., et al.
(author)
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Alcohol-attributed disease burden in four Nordic countries between 2000 and 2017 : Are the gender gaps narrowing? A comparison using the Global Burden of Disease, Injury and Risk Factor 2017 study
- 2021
-
In: Drug and Alcohol Review. - : Wiley. - 0959-5236 .- 1465-3362. ; 40:3, s. 431-442
-
Journal article (peer-reviewed)abstract
- Introduction and Aims. The gender difference in alcohol use seems to have narrowed in the Nordic countries, but it is not clear to what extent this may have affected differences in levels of harm. We compared gender differences in all-cause and cause-specific alcohol-attributed disease burden, as measured by disability-adjusted life-years (DALY), in four Nordic countries in 2000-2017, to find out if gender gaps in DALYs had narrowed. Design and Methods. Alcohol-attributed disease burden by DALYs per 100 000 population with 95% uncertainty intervals were extracted from the Global Burden of Disease database. Results. In 2017, all-cause DALYs in males varied between 2531 in Finland and 976 in Norway, and in females between 620 in Denmark and 270 in Norway. Finland had the largest gender differences and Norway the smallest, closely followed by Sweden. During 2000-2017, absolute gender differences in all-cause DALYs declined by 31% in Denmark, 26% in Finland, 19% in Sweden and 18% in Norway. In Finland, this was driven by a larger relative decline in males than females; in Norway, it was due to increased burden in females. In Denmark, the burden in females declined slightly more than in males, in relative terms, while in Sweden the relative decline was similar in males and females. Discussion and Conclusions. The gender gaps in harm narrowed to a different extent in the Nordic countries, with the differences driven by different conditions. Findings are informative about how inequality, policy and sociocultural differences affect levels of harm by gender.
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| 3. |
- Agardh, Emilie E., et al.
(author)
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Disease Burden Attributed to Drug use in the Nordic Countries : a Systematic Analysis for the Global Burden of Diseases, Injuries, and Risk Factors Study 2019
- 2023
-
In: International Journal of Mental Health and Addiction. - 1557-1874 .- 1557-1882.
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Journal article (peer-reviewed)abstract
- The Nordic countries share similarities in many social and welfare domains, but drug policies have varied over time and between countries. We wanted to compare differences in mortality and disease burden attributed to drug use over time. Using results from the Global Burden of Disease (GBD) study, we extracted age-standardized estimates of deaths, DALYs, YLLs and YLDs per 100 000 population for Denmark, Finland, Iceland, Norway, and Sweden during the years 1990 to 2019. Among males, DALY rates in 2019 were highest in Finland and lowest in Iceland. Among females, DALY rates in 2019 were highest in Iceland and lowest in Sweden. Sweden have had the highest increase in burden since 1990, from 252 DALYs to 694 among males, and from 111 to 193 among females. Norway had a peak with highest level of all countries in 2001-2004 and thereafter a strong decline. Denmark have had the most constant burden over time, 566-600 DALYs among males from 1990 to 2010 and 210-240 DALYs among females. Strict drug policies in Nordic countries have not prevented an increase in some countries, so policies need to be reviewed.
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| 4. |
- Cronberg, Carin, et al.
(author)
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Peripheral arterial disease.
- 2003
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In: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:1, s. 59-66
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Journal article (peer-reviewed)
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| 5. |
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| 6. |
- Danielsson, Conny, et al.
(author)
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Trace analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and WHO polychlorinated biphenyls in food using comprehensive two-dimensional gas chromatography with electron-capture detection
- 2005
-
In: Journal of Chromatography A. - : Elsevier BV. - 0021-9673 .- 1873-3778. ; 1086:1-2, s. 61-70
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Journal article (peer-reviewed)abstract
- Trace analysis of 2,3,7,8-polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and the 12 WHO-PCBs (four non-ortho and eight mono-ortho congeners that have been assigned toxic equivalence factors, TEFs, by the World Health Organisation) was conducted by comprehensive two-dimensional gas chromatography with a micro electron-capture detector (GC x GC-mu ECD). Four food matrices (fish oil from herring, spiked cows' milk, vegetable oil and an eel extract) were analysed by two GC x GC laboratories, and four GC-HRMS laboratories generated reference values. The two GC x GC laboratories used different column combinations for separating the target analytes. For the first dimension, non-polar DB-XLB and VF-1 columns were used, and for the second dimension, an LC-50 liquid crystalline column with unique selectivity for planar compounds. The congener-specific and total toxic equivalence (TEQ) data obtained using DB-XLB x LC-50 were in good agreement with results obtained by the GC-HRMS laboratories. The WHO-PCB data obtained with the VF-1 x LC-50 combination was also good, but the PCDD/F concentrations were sometimes overestimated due to matrix interferences. GC x GC-mu ECD using DB-XLB x LC-50 seems to fulfil the European Community requirements of a screening method for PCDD/F and WHO-PCB TEQ in food.
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| 7. |
- Danielsson, Gudmundur, et al.
(author)
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Flavonoid treatment in patients with healed venous ulcer: flow cytometry analysis suggests increased CD11b expression on neutrophil granulocytes in the circulation
- 2003
-
In: Vascular Medicine. - : SAGE Publications. - 1477-0377 .- 1358-863X. ; 8:2, s. 83-88
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Journal article (peer-reviewed)abstract
- The objective was to determine the activation of white blood cells (WBCs) and endothelial cells in patients with healed venous ulcer and the influence of the standing position and of treatment with flavonoids. Ten patients with a healed venous ulcer were treated with flavonoid substance (90% diosmin), 1000 mg three times daily for 30 days. Blood samples were taken from arm and dorsal foot veins before and after standing for 30 minutes. Blood sampling was performed before treatment, after three days, one month and three months. The activation of WBCs was determined by measuring adhesion molecule CD11b and CD18 expression on the surface of granulocytes and monocytes. In addition, interleukin 6 (IL-6), IL-8, soluble E-selectin (sE-selectin), sL-selectin and sICAM-1 levels in serum were quantified. The results showed that standing did not influence any of the measured parameters significantly. Expression of CD11b adhesion molecules on granulocytes was significantly up-regulated (p=0.044) after treatment with flavonoids for one month, but this increase was not significant (p=0.056) two months after the treatment period compared with the baseline level. The expression of CD18 remained unchanged. Baseline expression of CD11b or CD18 on monocytes did not change significantly during the study period. Neither was any significant change observed in the levels of IL-6, IL-8 or the soluble adhesion molecules. It was concluded that flavonoid treatment for 30 days increased the expression of CD11b adhesion molecules on circulating granulocytes. No general effect on the inflammatory process could be observed as assessed by levels of cytokines and soluble adhesion molecules. Possible explanations for these findings could be that a decreased number of primed granulocytes leave the circulation due to a changed WBC/endothelial cell interaction or that flavonoids have a direct effect on granulocytes. Further studies are needed to clarify the mode of action of flavonoids in chronic venous disease.
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| 8. |
- Danielsson, Gudmundur, et al.
(author)
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Percutaneous transluminal angioplasty of crural arteries: diabetes and other factors influencing outcome
- 2001
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In: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1532-2165 .- 1078-5884. ; 21:5, s. 432-436
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Journal article (peer-reviewed)abstract
- OBJECTIVE: to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) of the crural arteries. PATIENTS AND METHODS: a retrospective review of patients treated with PTA of at least one crural artery during an 8-year period (1990--1997). RESULTS: one hundred and fifty-five legs in 140 consecutive patients (mean age 74 years, range 38--91 years) were treated. In 76% a more proximal lesion was also treated. After 1 year, results were significantly better in non-diabetics (improvement rate of 66% vs 32%p <0.05). The outcome for patients with a combination of diabetes, heart disease and renal disease was significantly worse compared to all other patients with an improvement rate of only 9% after 1 year. Patients alive and not amputated at 1 year were significantly more common (p <0.05) among non-diabetics (90%), compared to diabetics (66%). The 1-year mortality for the whole group was 15%, significantly higher for diabetic patients (p =0.04). CONCLUSION: PTA of crural arteries produces reasonably good results in non-diabetic patients. Diabetic patients were doing worse than non-diabetics after a year, though 1-month results were not significantly different. Patients with diabetes, heart disease and renal disease make a high-risk group that has a significantly worse outcome.
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| 9. |
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| 10. |
- Fagerberg, Linn, et al.
(author)
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Analysis of the human tissue-specific expression by genome-wide integration of transcriptomics and antibody-based proteomics
- 2014
-
In: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 13:2, s. 397-406
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Journal article (peer-reviewed)abstract
- Global classification of the human proteins with regards to spatial expression patterns across organs and tissues is important for studies of human biology and disease. Here, we used a quantitative transcriptomics analysis (RNA-Seq) to classify the tissue-specific expression of genes across a representative set of all major human organs and tissues and combined this analysis with antibody- based profiling of the same tissues. To present the data, we launch a new version of the Human Protein Atlas that integrates RNA and protein expression data corresponding to 80% of the human protein-coding genes with access to the primary data for both the RNA and the protein analysis on an individual gene level. We present a classification of all human protein-coding genes with regards to tissue-specificity and spatial expression pattern. The integrative human expression map can be used as a starting point to explore the molecular constituents of the human body.
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| 11. |
- Haglund, Peter, et al.
(author)
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GCxGC-ECD a promising method for the determination of dioxins and dioxin-like PCBs in food and feed
- 2008
-
In: Analytical and Bioanalytical Chemistry. - : Springer. - 1618-2642 .- 1618-2650. ; 390:7, s. 1815-1827
-
Journal article (peer-reviewed)abstract
- There is a need for cost-efficient alternatives to gas chromatography (GC)–high-resolution mass spectrometry (HRMS) for the analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) in food and feed. Comprehensive two-dimensional GC–micro electron capture detection (GC×GC-μECD) was tested and all relevant (according to the World Health Organisation, WHO) PCDD/Fs and PCBs could be separated when using a DB-XLB/LC-50 column combination. Validation tests by two laboratories showed that detectability, repeatability, reproducibility and accuracy of GC×GC-μECD are all statistically consistent with GC-HRMS results. A limit of detection of 0.5 pg WHO PCDD/F tetrachlorodibenzo-p-dioxin equivalency concentration per gram of fish oil was established. The reproducibility was less than 10%, which is below the recommended EU value for reference methods (less than 15%). Injections of vegetable oil extracts spiked with PCBs, polychlorinated naphthalenes and diphenyl ethers at concentrations of 200 ng/g showed no significant impact on the dioxin results, confirming in that way the robustness of the method. The use of GC×GC-μECD as a routine method for food and feed analysis is therefore recommended. However, the data evaluation of low dioxin concentrations is still laborious owing to the need for manual integration. This makes the overall analysis costs higher than those of GC-HRMS. Further developments of software are needed (and expected) to reduce the data evaluation time. Combination of the current method with pressurised liquid extraction with in-cell cleanup will result in further reduction of analysis costs.
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| 12. |
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| 13. |
- Nordanstig, Joakim, et al.
(author)
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Mortality with Paclitaxel-Coated Devices in Peripheral Artery Disease.
- 2020
-
In: The New England journal of medicine. - : Massachusetts Medical Society. - 1533-4406 .- 0028-4793. ; 383, s. 2538-46
-
Journal article (peer-reviewed)abstract
- The results of a recent meta-analysis aroused concern about an increased risk of death associated with the use of paclitaxel-coated angioplasty balloons and stents in lower-limb endovascular interventions for symptomatic peripheral artery disease.We conducted an unplanned interim analysis of data from a multicenter, randomized, open-label, registry-based clinical trial. At the time of the analysis, 2289 patients had been randomly assigned to treatment with drug-coated devices (the drug-coated-device group, 1149 patients) or treatment with uncoated devices (the uncoated-device group, 1140 patients). Randomization was stratified according to disease severity on the basis of whether patients had chronic limb-threatening ischemia (1480 patients) or intermittent claudication (809 patients). The single end point for this interim analysis was all-cause mortality.No patients were lost to follow-up. Paclitaxel was used as the coating agent for all the drug-coated devices. During a mean follow-up of 2.49 years, 574 patients died, including 293 patients (25.5%) in the drug-coated-device group and 281 patients (24.6%) in the uncoated-device group (hazard ratio, 1.06; 95% confidence interval, 0.92 to 1.22). At 1 year, all-cause mortality was 10.2% (117 patients) in the drug-coated-device group and 9.9% (113 patients) in the uncoated-device group. During the entire follow-up period, there was no significant difference in the incidence of death between the treatment groups among patients with chronic limb-threatening ischemia (33.4% [249 patients] in the drug-coated-device group and 33.1% [243 patients] in the uncoated-device group) or among those with intermittent claudication (10.9% [44 patients] and 9.4% [38 patients], respectively).In this randomized trial in which patients with peripheral artery disease received treatment with paclitaxel-coated or uncoated endovascular devices, the results of an unplanned interim analysis of all-cause mortality did not show a difference between the groups in the incidence of death during 1 to 4 years of follow-up. (Funded by the Swedish Research Council and others; ClinicalTrials.gov number, NCT02051088.).
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| 14. |
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| 15. |
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| 16. |
- Thul, Peter J., et al.
(author)
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A subcellular map of the human proteome
- 2017
-
In: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 356:6340
-
Journal article (peer-reviewed)abstract
- Resolving the spatial distribution of the human proteome at a subcellular level can greatly increase our understanding of human biology and disease. Here we present a comprehensive image-based map of subcellular protein distribution, the Cell Atlas, built by integrating transcriptomics and antibody-based immunofluorescence microscopy with validation by mass spectrometry. Mapping the in situ localization of 12,003 human proteins at a single-cell level to 30 subcellular structures enabled the definition of the proteomes of 13 major organelles. Exploration of the proteomes revealed single-cell variations in abundance or spatial distribution and localization of about half of the proteins to multiple compartments. This subcellular map can be used to refine existing protein-protein interaction networks and provides an important resource to deconvolute the highly complex architecture of the human cell.
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| 17. |
- Thörne, Johan, et al.
(author)
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Intraoperative angioscopy may improve the outcome of in situ saphenous vein bypass grafting: a prospective study.
- 2002
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In: Journal of Vascular Surgery. - : Elsevier BV. - 1097-6809 .- 0741-5214. ; 35:4, s. 759-765
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: To find out whether intraoperative angioscopic assistance has any effect on graft outcome in patients with critical leg ischemia.Material And Methods: One hundred one patients requiring a below-knee bypass were assigned to undergo in situ saphenous vein bypass with or without intraoperative angioscopic assistance; otherwise treated similarly including preoperative duplex vein mapping, intraoperative graft flow measurements, and angiography. Data on operative details, morbidity, hospital stay, and graft patency were collected prospectively and compared. All patients were followed up for 12 months. RESULTS: The group that underwent angioscopy (A) and the control group (B) were similar in all respects, except for the number of patients enrolled in the groups (32 and 69, respectively). Angioscopy revealed incompletely destructed valves in 34 patients (range, 0 to 5; mean 1), undiagnosed vein branches in 111 patients (mean 4.3), and partly occluding thrombus in 5 patients. The number of postoperative arteriovenous fistulas with signs of failing graft and a need for angiographic or surgical reintervention were significantly higher in group B (P <.0001). The 1-year primary patency rate was significantly better in group A (P <.01), but the primary assisted and secondary patency rates did not differ between the groups. CONCLUSIONS: Angioscopic assistance has an impact on primary graft patency, minimizes the risk for graft failure and thus reduces the need for reintervention by allowing identification of persistent saphenous vein branches, incomplete valve destruction, and partly occluding graft thrombus without adding extra operative time.
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| 18. |
- Uhlén, Mathias, et al.
(author)
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The human secretome
- 2019
-
In: Science Signaling. - : American Association for the Advancement of Science (AAAS). - 1945-0877 .- 1937-9145. ; 12:609
-
Journal article (peer-reviewed)abstract
- The proteins secreted by human cells (collectively referred to as the secretome) are important not only for the basic understanding of human biology but also for the identification of potential targets for future diagnostics and therapies. Here, we present a comprehensive analysis of proteins predicted to be secreted in human cells, which provides information about their final localization in the human body, including the proteins actively secreted to peripheral blood. The analysis suggests that a large number of the proteins of the secretome are not secreted out of the cell, but instead are retained intracellularly, whereas another large group of proteins were identified that are predicted to be retained locally at the tissue of expression and not secreted into the blood. Proteins detected in the human blood by mass spectrometry-based proteomics and antibody-based immuno-assays are also presented with estimates of their concentrations in the blood. The results are presented in an updated version 19 of the Human Protein Atlas in which each gene encoding a secretome protein is annotated to provide an open-access knowledge resource of the human secretome, including body-wide expression data, spatial localization data down to the single-cell and subcellular levels, and data about the presence of proteins that are detectable in the blood.
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| 19. |
- Abdellah, Tebani, et al.
(author)
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Integration of molecular profiles in a longitudinal wellness profiling cohort.
- 2020
-
In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
-
Journal article (peer-reviewed)abstract
- An important aspect of precision medicine is to probe the stability in molecular profiles among healthy individuals over time. Here, we sample a longitudinal wellness cohort with 100 healthy individuals and analyze blood molecular profiles including proteomics, transcriptomics, lipidomics, metabolomics, autoantibodies andimmune cell profiling, complementedwith gut microbiota composition and routine clinical chemistry. Overall, our results show high variation between individuals across different molecular readouts, while the intra-individual baseline variation is low. The analyses show that each individual has a unique and stable plasma protein profile throughout the study period and that many individuals also show distinct profiles with regards to the other omics datasets, with strong underlying connections between the blood proteome and the clinical chemistry parameters. In conclusion, the results support an individual-based definition of health and show that comprehensive omics profiling in a longitudinal manner is a path forward for precision medicine.
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| 20. |
- Agardh, Emilie E., et al.
(author)
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Alcohol and type 2 diabetes : The role of socioeconomic, lifestyle and psychosocial factors
- 2019
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In: Scandinavian Journal of Public Health. - : SAGE Publications. - 1403-4948 .- 1651-1905. ; 47:4, s. 408-416
-
Journal article (peer-reviewed)abstract
- AIMS: We investigate (a) alcohol consumption in association with type 2 diabetes, taking heavy episodic drinking (HED), socioeconomic, health and lifestyle, and psychosocial factors into account, and (b) whether a seemingly protective effect of moderate alcohol consumption on type 2 diabetes persists when stratified by occupational position.METHODS: This population-based longitudinal cohort study comprises 16,223 Swedes aged 18-84 years who answered questionnaires about lifestyle, including alcohol consumption in 2002, and who were followed-up for self-reported or register-based diabetes in 2003-2011. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated in a multivariable-adjusted logistic regression model for all participants and stratified by high and low occupational position. We adjusted for HED, socioeconomic (occupational position, cohabiting status and unemployment), health and lifestyle (body mass index (BMI), blood pressure, smoking, physical inactivity, poor general health, anxiety/depression and psychosocial (low job control and poor social support) characteristics one by one, and the sets of these factors.RESULTS: Moderate consumption was inversely associated with type 2 diabetes after controlling for health and lifestyle (OR=0.47; 95% CI: 0.29-0.79) and psychosocial factors (OR=0.40; 95% CI: 0.22-0.79) when compared to non-drinkers. When adjusting for socioeconomic factors, there was still an inverse but non-significant association (OR=0.59; 95% CI: 0.35-1.00). In those with high occupational position, there was no significant association between moderate consumption and type 2 diabetes after adjusting for socioeconomic (OR=0.67; 95% CI: 0.3-1.52), health and lifestyle (OR=0.70; 95% CI: 0.32-1.5), and psychosocial factors (OR=0.75; 95% CI: 0.23-2.46). On the contrary, in those with low occupational position, ORs decreased from 0.55 (95% CI: 0.28-1.1) to 0.35 (95% CI: 0.15-0.82) when adjusting for psychosocial factors, a decrease that was solely due to low job control. HED did not influence any of these associations.CONCLUSIONS: Moderate alcohol consumption is associated with a lower risk of type 2 diabetes, after adjusting for HED, health and lifestyle, and psychosocial characteristics. The association was inverse but non-significant after adjusting for socioeconomic factors. When stratified by occupational position, there was an inverse association only in those with low occupational position and after adjusting for low job control.
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| 21. |
- Al-Chalabi, Ammar, et al.
(author)
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July 2017 ENCALS statement on edaravone
- 2017
-
In: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. - : TAYLOR & FRANCIS LTD. - 2167-8421 .- 2167-9223. ; 18:7-8, s. 471-474
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Journal article (peer-reviewed)abstract
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| 22. |
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| 23. |
- Asif, Muhammad H, et al.
(author)
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Functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose
- 2010
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In: Biosensors & Bioelectronics. - : Elsevier BV. - 1873-4235 .- 0956-5663. ; 25:10, s. 2205-2211
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Journal article (peer-reviewed)abstract
- In this article, we report a functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose. To adjust the sensor for intracellular glucose measurements, we grew hexagonal ZnO nanorods on the tip of a silver-covered borosilicate glass capillary (0.7 mu m diameter) and coated them with the enzyme glucose oxidase. The enzyme-coated ZnO nanorods exhibited a glucose-dependent electrochemical potential difference versus an Ag/AgCl reference microelectrode. The potential difference was linear over the concentration range of interest (0.5-1000 mu M). The measured glucose concentration in human adipocytes or frog oocytes using our ZnO-nanorod sensor was consistent with values of glucose concentration reported in the literature; furthermore, the sensor was able to show that insulin increased the intracellular glucose concentration. This nanoelectrode device demonstrates a simple technique to measure intracellular glucose concentration. (C) 2010 Elsevier B.V. All rights reserved.
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| 24. |
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| 25. |
- Asoodar, Mohsen, et al.
(author)
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A Condition Monitoring Scheme for Semiconductor Devices in Modular Multilevel Converters with Cascaded H-Bridge Submodules
- 2022
-
In: 24th European Conference on Power Electronics and Applications, EPE 2022 ECCE Europe. - : Institute of Electrical and Electronics Engineers Inc..
-
Conference paper (peer-reviewed)abstract
- In this paper, a novel online semiconductor device monitoring scheme is presented. The condition monitoring (CM) scheme is based on measuring the ON-state voltage drop of semiconductor devices, and tracking the changes in their ON-state resistance. The proposed solution measures the ON-state voltage of semiconductor devices at a controlled and readily measurable temperature. This allows for accurate CM of semiconductors as it decouples temperature related and degradation related changes in the ON-state voltage. The temperature decoupling is achieved using natural switching redundancies available to modular multilevel converter systems. Hence, the proposed CM scheme does not interfere with the output voltages and currents generated by the converter.
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| 26. |
- Asoodar, Mohsen, et al.
(author)
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Accurate Condition Monitoring of Semiconductor Devices in Cascaded H-Bridge Modular Multilevel Converters
- 2023
-
In: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 38:3, s. 3870-3884
-
Journal article (peer-reviewed)abstract
- This article presents an online condition monitoring (CM) scheme for semiconductors used in modular multilevel converters (MMCs) that comprise cascaded H-bridge submodules. The CM algorithm is based on detecting changes in the ON-state resistance of the semiconductors over time. The proposed method is shown to successfully perform a curve tracing of semiconductors in MMCs while the semiconductor junction remains at a temperature that is readily measurable and undergoes minute changes during the measurement process. The ON-state resistance value is estimated from the measured ON-state voltage drop of the semiconductors and the measured arm current. Measuring the ON-state resistance at known temperatures allows for separating temperature-dependent variations of the ON-state resistance from age-dependent variations of this parameter. Suitable methods for reducing the effect of noise on the curve-traced data are proposed, and a recursive least square estimator is used to extract the optimum ON-state resistance from the traced v(CE) - i
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| 27. |
- Asoodar, Mohsen, et al.
(author)
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Online Health Monitoring of DC-Link Capacitors in Modular Multilevel Converters for FACTS and HVDC Applications
- 2021
-
In: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 36:12, s. 13489-13503
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Journal article (peer-reviewed)abstract
- This article presents an online health monitoring scheme for dc capacitors in modular multilevel converters (MMCs). The health monitoring algorithm is based on detecting changes in the dc capacitance value over time. The proposed algorithm only utilizes measurements that are typically available in flexible alternating current transmission systems and high-voltage direct current applications. Hence, in the proposed estimation method, no additional sensors are used. The estimation scheme considers the presence of noise in voltage and current measurements, and utilizes a recursive least square estimator in conjunction with a special low-pass filter to minimize the estimation errors. Simulation results of a hardware replica, as well as experimental results on a low-power MMC prototype show that the proposed scheme can identify the dc-link capacitance value with a maximum error of 1%.
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| 28. |
- Asoodar, Mohsen, et al.
(author)
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Temperature Considerations for Online Health Monitoring of DC-Link Capacitors in Modular Multilevel Converters
- 2021
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In: 2021 23rd European Conference on Power Electronics and Applications, EPE 2021 ECCE Europe. - : Institute of Electrical and Electronics Engineers Inc..
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Conference paper (peer-reviewed)abstract
- In this paper, the effect of temperature on online heath monitoring of dc capacitors in modular multilevel converters (MMCs) is studied. The submodule capacitance value is considered as the main indicator of health. Both self heating and ambient temperature are considered as sources of temperature variation. The study is conducted on a single phase MMC with full-bridge submodules. However, a similar analysis can be used for half-bridge MMCs and multiphase MMCs as well. The thermal behaviour of the capacitors is explained analytically and simulated using a simplified Cauer model. The effect of temperature on the estimated capacitance values is shown, and a method for reducing this effect is proposed. The results are verified using simulations in MATLAB/Simulink.
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| 29. |
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| 30. |
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| 31. |
- Bergh, Johan, 1983-, et al.
(author)
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Structural and kinetic analysis of protein-aggregate strains in vivo using binary epitope mapping
- 2015
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In: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 112:14, s. 4489-4494
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Journal article (peer-reviewed)abstract
- Despite considerable progress in uncovering the molecular details of protein aggregation in vitro, the cause and mechanism of protein-aggregation disease remain poorly understood. One reason is that the amount of pathological aggregates in neural tissue is exceedingly low, precluding examination by conventional approaches. We present here a method for determination of the structure and quantity of aggregates in small tissue samples, circumventing the above problem. The method is based on binary epitope mapping using anti-peptide antibodies. We assessed the usefulness and versatility of the method in mice modeling the neurodegenerative disease amyotrophic lateral sclerosis, which accumulate intracellular aggregates of superoxide dismutase-1. Two strains of aggregates were identified with different structural architectures, molecular properties, and growth kinetics. Both were different from superoxide dismutase-1 aggregates generated in vitro under a variety of conditions. The strains, which seem kinetically under fragmentation control, are associated with different disease progressions, complying with and adding detail to the growing evidence that seeding, infectivity, and strain dependence are unifying principles of neurodegenerative disease.
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| 32. |
- Bergstrand, Katarina, et al.
(author)
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Hur tänker egentligen Naturvårdsverket? : Debatt
- 2024
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In: Svenska dagbladet. - Stockholm.
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Journal article (pop. science, debate, etc.)abstract
- Debattartikeln tar upp Naturvårdsverkets förhållningssätt till att klassa elcykeln och att nyttja den för att besöka naturområden.
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| 33. |
- Bignert, Anders, et al.
(author)
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Comments Concerning the National Swedish Contaminant Monitoring Programme in Marine Biota, 2008
- 2008
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Reports (other academic/artistic)abstract
- This report gives a summary of the monitoring activities within the national Swedish contaminant programme in marine biota. It is the result from the joint efforts of: the Department of Applied Environmental Science at Stockholm University (analyses of organochlorines), the Department of Environmental Assessment at Swedish University of Agricultural Sciences (analyses of heavy metals), Department of Chemistry at Umeå University (analyses of PCDD/PCDF) and the Department of Contaminant Research at the Swedish Museum of Natural History (co-ordination, sample collection administration, sample preparation, recording of biological variables, storage of frozen biological tissues in the Environmental Specimen Bank for retrospective studies, data preparation and statistical evaluation). The monitoring programme is financiated by the Environmental Protection Agency (EPA) in Sweden.The data of concern in this report represent the bioavailable part of the investigated contaminants i.e. the part that has virtually passed through the biological membranes and may cause toxic effects. The objectives of the monitoring program in marine biota could be summarised as follows:• to estimate the levels and the normal variation of various contaminants in marine biota from several representative sites, uninfluenced by local sources, along the Swedish coasts. The goal is to describe the general contaminant load and to supply reference values for regional and local monitoring programmes• to monitor long term time trends and to estimate the rate of found changes.quantified objective: to detect an annual change of 10% within a time period of 10 years with a power of 80% at a significance level of 5%.• to estimate the response in marine biota of measures taken to reduce the discharges of various contaminantsquantified objective: to detect a 50% decrease within a time period of 10 years with a power of 80% at a significance level of 5%.• to detect incidents of regional influence or widespread incidents of ‘Chernobyl’- character and to act as watchdog monitoring to detect renewed usage of banned contaminants.quantified objective: to detect an increase of 200% a single year with a power of 80% at a significance level of 5%.• to indicate large scale spatial differencesquantified objective: to detect differences of a factor 2 between sites with a power of 80% at a significance level of 5%.• to explore the development and regional differences of the composition and pattern of e.g. PCB’s, HCH’s and DDT’s as well as the ratios between various contaminants.• the time series are also relevant for human consumption since important commercial fish species like herring and cod are sampled. A co-operation with the Swedish Food Administration is established. Sampling is also co-ordinated with SSI (Swedish Radiation Protection Authority) for analysing radionuclides in fish and blue mussels (HELCOM, 1992).• all analysed, and a large number of additional specimens, of the annually systematically collected material are stored frozen in the Environmental Specimen Bank.. This invaluable4material enables future retrospective studies of contaminants impossible to analyse today as well as control analyses of suspected analytical errors.• although the programme is focused on contaminant concentration in biota, also the development of biological variables like e.g. condition factor (CF), liver somatic index (LSI) and fat content are monitored at all sites. At a few sites, integrated monitoring with fish physiology and population are running in co-operation with the University of Gothenburg and the Swedish Board of Fisheries.• experiences from the national programme with several time series of over 25 years can be used in the design of regional and local monitoring programmes.• the perfectly unique material of high quality and long time series is further used to explore relationships among biological variables and contaminant concentrations in various tissues; the effects of changes in sampling strategy, the estimates of variance components and the influence on the concept of power etc.• the accessibility of high quality data collected and analysed in a consistent manner is an indispensable prerequisite to evaluate the validity of hypothesis and models concerning the fate and distribution of various contaminants. It could furthermore be used as input of ‘real’ data in the ongoing model building activities concerning marine ecosystems in general and in the Baltic and North Sea environment in particular.• the contaminant programme in marine biota constitute an integrated part of the national monitoring activities in the marine environment as well as of the international programmes within ICES, OSPARCOM and HELCOM.The present report displays the timeseries of analysed contaminants in biota and summarises the results from the statistical treatment. It does not in general give the background or explanations to significant changes found in the timeseries. Increasing concentrations thus, urge for intensified studies.Short comments are given for temporal trends as well as for spatial variation and, for some contaminants, differences in geometric mean concentration between various species caught at the same site. Sometimes notes of seasonal variation and differences in concentration between tissues in the same species are given. This information could say something about the relative appropriateness of the sampled matrix and be of help in designing monitoring programmes. In the temporal trend part, an extract of the relevant findings is summarised in the 'conclusion'-paragraph. It should be stressed though, that geographical differences may not reflect antropogenic influence but may be due to factors like productivity, temperature, salinity etc.The report is continuously updated. The date of the latest update is reported at the beginning of each chapter. The creation date of each figure is written in the lower left corner.
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| 34. |
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| 35. |
- Bignert, Anders, et al.
(author)
-
Comments Concerning the National Swedish Contaminant Monitoring Programme in Marine Biota, 2015
- 2015
-
Reports (other academic/artistic)abstract
- The environmental toxicants examined in this report can be classified into five groups – heavy metals, chlorinated compounds, brominated flame retardants, polyaromatic hydrocarbons and perfluorinated compounds. Each of these contaminants have been examined from various sites for up to six different fish species, in blue mussels, and in guillemot eggs, for varying lengths of time. The following summary examines overall trends, spatial and temporal, for the five groups.Condition and Fat ContentCondition and fat content in different species tended to follow the same pattern at the same sites, with a few exceptions. Most of the fish species generally displayed a decreasing trend in both condition and fat content at most sites examined. Exceptions to this were increases in condition factor seen in cod liver at Fladen, perch muscle at Kvädöfjärden, and for herring at Ängskärsklubb in spring. Also, an increase in fat content was seen during the most recent ten years for herring at Ängskärsklubb in spring. There were also some sites where no log linear trends were seen.Heavy MetalsDue to a change in methods for metal analysis (not mercury) in 2004, values between 2003 and 2007 should be interpreted with care. From 2009 metals are analyzed at ACES, Stockholm University.Generally, higher mercury concentrations are found in the Bothnian Bay, but also from one station in the Northern parts of Baltic Proper, compared to other parts of the Swedish coastline. The time series show varying concentrations over the study period. The longer time series in guillemot egg and spring-caught herring from the southern Bothnian Sea and southern Baltic Proper show significant decreases of mercury. On the other hand, increasing concentrations are seen in e.g., cod muscle, but the concentrations are fairly low compared to measured concentrations in perch from fresh water and coastal sites. In most cases, the mercury concentrations are above the EQSbiota of 20 ng/g wet weight.Lead is generally decreasing over the study period (in time series of sufficient length), supposedly due to the elimination of lead in gasoline. The highest concentrations are seen in the southern part of the Baltic Sea. Elevated lead concentrations between 2003 and 2007 (e.g. Harufjärden) should be viewed with caution (see above regarding change in analysis methods). Lead concentrations are below the suggested target level at all stations.Cadmium concentrations show varying non-linear trends over the monitored period. It is worth noting that despite several measures taken to reduce discharges of cadmium, generally the most recent concentrations are similar to concentrations measured 30 yearsago in the longer time series. Cadmium concentrations in herring and perch are all below the suggested target level of 160 μg/kg wet weight.The reported nickel concentrations show no consistent decreasing trends. Some series begin with two elevated values that exert a strong leverage effect on the regression line and may give a false impression of decreasing trends. Chromium generally shows decreasing concentrations, possibly explained by a shift in analytical method. The essential trace metals, copper and zinc, show no consistent trends during the monitored period.Generally higher concentrations of arsenic and silver are found along the west coast compared to other parts of the Sweadish coast line. However for silver a few stations in the Bothnian Sea and Bothnian Bay show comparable concentrations to the west coast stations.Chlorinated CompoundsGenerally, a decreasing concentrations were observed for all compounds (DDT’s, PCB’s, HCH’s, HCB) in all species examined, with a few exceptions, such as no change in TCDD-equivalents being seen in herring muscle (except at Änskärsklubb where very high concentrations at the beginning of the sampling period were seen and also at the west coast station Fladen). The longer time-series in guillemot also show a marked decrease in TCDD-equivalents from the start in the late 1960s until about 1985 from where no change occurred for many years, however, during the most recent ten years a decrease in the concentration is seen. Concentrations of DDE and CB-118 are for some species and sites still above their respective target levels.The chlorinated compounds generally show higher concentrations in the Bothnian Sea and/or Baltic Proper when compared to the Bothnian Bay and the Swedish west coast.Brominated Flame RetardantsElevated levels of HBCDD are seen in sites from the Baltic Proper, while the investigated PBDEs show higher concentrations in the Bothnian Bay. In addition, lower concentrations of all investigated PBDEs and HBCDD are seen on the Swedish west coast compared to the east coast. Temporally, significant increases in BDE-47, -99 and -100 have been seen in guillemot eggs since the late 1960s until the early 1990s, where concentrations then began to show decreases. Also, the concentration of HBCDD in guillemot eggs shows a decrease during the most recent ten years. For fish and blue mussels, BDE-47, -99, and -153 decreased at some sites and showed no trend at other sites. The concentration of HBCDD in fish and blue mussels showed inconsistent trends. The concentration of HBCDD is below the EQSbiota of 167 μg/kg wet weight for all fish species from all areas, while the concentration of BDE-47 alone is above the EQSbiota for sumPBDE of 0.0085 ng/g wet weight.PAHsOnly blue mussels have been examined for spatial differences in PAH concentrations. Concentration of ΣPAH was found to be higher from Kvädöfjärden in the Baltic Proper compared to stations at the West coast, but individual PAHs showed varying spatial patterns. Over time, acenaphthalene was rarely found above the detection limit. Significant decreasing trends were observed for ΣPAH, chrysene, fluoranthene and pyrene at Fjällbacka; for naphthalene at Kvädöfjärden; and for pyrene at Fladen.All time series where concentrations of various PAHs were compared with the target value based on OSPAR Ecological Assessment Criteria, or EC Environmental Quality Standards were below the target value.PFASsPFHxS and PFOS show a similar spatial pattern, but PFOS concentrations were approximately 25 times higher than PFHxS levels. The distribution of PFOS is quite homogenous along the Swedish coast but with somewhat higher concentrations in the Baltic Proper. PFOS concentrations in guillemot eggs are about 100-200 times higher than in herring liver. An overall increasing concentration of PFOS in guillemot eggs has been observed throughout the whole time period, however, during the most recent ten years, a change of direction is detected. The longer herring time series from Harufjärden, Landsort, and Utlängan show increasing concentrations for PFOS and most carboxylates. For FOSA, on the other hand, decreasing concentrations are seen during the most recent ten years.Organotin compoundsThe majority of the analysed tinorganic compounds showed concentrations below LOQ. However TBT and DPhT showed concentrations above LOQ at all stations with highest reported concentrations in fish from Örefjärden in the northern part of Bothnian Sea.
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| 36. |
- Bignert, Anders, et al.
(author)
-
Övervakning av metaller och organiska miljögifter i marin biota, 2009
- 2009
-
Reports (other academic/artistic)abstract
- This report gives a summary of the monitoring activities within the national Swedish contaminant programme in marine biota. It is the result from the joint efforts of: the Department of Applied Environmental Science at Stockholm University (analyses of organochlorines), the Department of Environmental Assessment at Swedish University of Agricultural Sciences (analyses of heavy metals), Department of Chemistry at Umeå University (analyses of PCDD/PCDF) and the Department of Contaminant Research at the Swedish Museum of Natural History (co-ordination, sample collection administration, sample preparation, recording of biological variables, storage of frozen biological tissues in the Environmental Specimen Bank for retrospective studies, data preparation and statistical evaluation). The monitoring programme is financiated by the Environmental Protection Agency (EPA) in Sweden. The data of concern in this report represent the bioavailable part of the investigated contaminants i.e. the part that has virtually passed through the biological membranes and may cause toxic effects. The objectives of the monitoring program in marine biota could be summarised as follows: to estimate the levels and the normal variation of various contaminants in marine biota from several representative sites, uninfluenced by local sources, along the Swedish coasts. The goal is to describe the general contaminant load and to supply reference values for regional and local monitoring programmes to monitor long term time trends and to estimate the rate of found changes. quantified objective: to detect an annual change of 10% within a time period of 10 years with a power of 80% at a significance level of 5%. to estimate the response in marine biota of measures taken to reduce the discharges of various contaminants quantified objective: to detect a 50% decrease within a time period of 10 years with a power of 80% at a significance level of 5%. to detect incidents of regional influence or widespread incidents of ‘Chernobyl’-character and to act as watchdog monitoring to detect renewed usage of banned contaminants. quantified objective: to detect an increase of 200% a single year with a power of 80% at a significance level of 5%. to indicate large scale spatial differences quantified objective: to detect differences of a factor 2 between sites with a power of 80% at a significance level of 5%. to explore the development and regional differences of the composition and pattern of e.g. PCB’s, HCH’s, DDT’s, PCDD/F, PBDE/HBCD, PAH’s and PFC’s as well as the ratios between various contaminants. the time series are also relevant for human consumption since important commercial fish species like herring and cod are sampled. A co-operation with the Swedish Food Administration is established. Sampling is also co-ordinated with SSI (Swedish Radiation Protection Authority) for analysing radionuclides in fish and blue mussels (HELCOM,1992). all analysed, and a large number of additional specimens, of the annually systematically collected material are stored frozen in the Environmental Specimen Bank. This invaluable material enables future retrospective studies of contaminants impossible to analyse today as well as control analyses of suspected analytical errors. although the programme is focused on contaminant concentration in biota, also the development of biological variables like e.g. condition factor (CF), liver somatic index (LSI) and fat content are monitored at all sites. At a few sites, integrated monitoring with fish physiology and population are running in co-operation with the University of Gothenburg and the Swedish Board of Fisheries. experiences from the national programme with several time series of over 30 years can be used in the design of regional and local monitoring programmes. the perfectly unique material of high quality and long time series is further used to explore relationships among biological variables and contaminant concentrations in various tissues; the effects of changes in sampling strategy, the estimates of variance components and the influence on the concept of power etc. the accessibility of high quality data collected and analysed in a consistent manner is an indispensable prerequisite to evaluate the validity of hypothesis and models concerning the fate and distribution of various contaminants. It could furthermore be used as input of ‘real’ data in the ongoing model building activities concerning marine ecosystems in general and in the Baltic and North Sea environment in particular. the contaminant programme in marine biota constitute an integrated part of the national monitoring activities in the marine environment as well as of the international programmes within ICES, OSPARCOM, HELCOM and EU. The present report displays the timeseries of analysed contaminants in biota and summarises the results from the statistical treatment. It does not in general give the background or explanations to significant changes found in the timeseries. Increasing concentrations thus, urge for intensified studies. Short comments are given for temporal trends as well as for spatial variation and, for some contaminants, differences in geometric mean concentration between various species caught at the same site. Sometimes notes of seasonal variation and differences in concentration between tissues in the same species are given. This information could say something about the relative appropriateness of the sampled matrix and be of help in designing monitoring programmes. In the temporal trend part, an extract of the relevant findings is summarised in the 'conclusion'-paragraph. It should be stressed though, that geographical differences may not reflect antropogenic influence but may be due to factors like productivity, temperature, salinity etc. The report is continuously updated. The date of the latest update is reported at the beginning of each chapter. The creation date of each figure is written in the lower left corner.
|
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| 37. |
- Bignert, Anders, et al.
(author)
-
Övervakning av metaller och organiska miljögifter i marin biota, 2011
- 2011
-
Reports (other academic/artistic)abstract
- The environmental toxicants examined in this report can be classified into five groups –heavy metals, chlorinated compounds, brominated flame retardants, polyaromatichydrocarbons and perfluorinated compounds. Each of these contaminants has beenexamined from various sites for up to six different fish species, in blue mussels, and inguillemot eggs, for varying lengths of time. The following summary examines overalltrends, spatial and temporal, for the five groups.Condition and Fat ContentCondition and fat content in different species tended to follow the same pattern at the samesites, with a few exceptions. Most of the fish species generally displayed a decreasing trendin both condition and fat content at most sites examined. Exceptions to this were increasesin fat content seen in herring (the last ten years) and cod at Fladen; an increase in conditionfor herring at Ängskärsklubb in spring; and in perch, a decrease in fat content atKvädöfjärden but no trend in condition for the same site.Heavy MetalsDue to a change in methods for metal analysis (not Hg) in 2004, values between 2003 and2007 should be interpreted with care. From 2009 metals are analyzed at ITM, Stockholmuniversity.The longer time series in guillemot egg and spring-caught herring from the southernBothnian Sea and southern Baltic Proper show significant decreases of mercury. Theherring site in the southern Bothnain Sea indicates a local Hg-source. The rest of the timeseries show varying concentrations over the study period, and even increasing trends in e.g.cod muscle and blue mussels, but the concentrations are fairly low compared to measuredconcentrations in perch from fresh water and coastal sites. However, in most cases, theseconcentrations are above the newly suggested EU-target level of 20 ng/g wet weight.Lead is generally decreasing over the study period (in time series of sufficient length),supposedly due to the elimination of lead in gasoline. Elevated lead concentrations between2003 and 2007 (e.g. Harufjärden) should be viewed with caution (see above regardingchange in analysis methods).Cadmium concentrations show varying non-linear trends over the monitored period. It isworth noting that despite several measures taken to reduce discharges of cadmium,generally the most recent concentrations are similar to concentrations measured 30 yearsago in the longer time series.The reported nickel concentrations show no consistent decreasing trends. Some series beginwith two elevated values that exert a strong leverage effect on the regression line and maygive a false impression of decreasing trends. Chromium generally shows decreasing trends,possibly explained by a shift in analytical method. The essential trace metals, copper andzinc, show no consistent trends during the monitored period.
|
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| 38. |
- Bignert, Anders, et al.
(author)
-
Övervakning av metaller och organiska miljögifter i marin biota, 2012
- 2012
-
Reports (other academic/artistic)abstract
- The environmental toxicants examined in this report can be classified into five groups –heavy metals, chlorinated compounds, brominated flame retardants, polyaromatichydrocarbons and perfluorinated compounds. Each of these contaminants has beenexamined from various sites for up to six different fish species, in blue mussels, and inguillemot eggs, for varying lengths of time. The following summary examines overalltrends, spatial and temporal, for the five groups.Condition and Fat ContentCondition and fat content in different species tended to follow the same pattern at the samesites, with a few exceptions. Most of the fish species generally displayed a decreasing trendin both condition and fat content at most sites examined. Exceptions to this were increasesin fat content and condition factor seen in cod liver at both sites; an increase in conditionfor herring at Ängskärsklubb in spring; and in perch and eelpout, a decrease in fat content atKvädöfjärden (perch) and Väderöarna (eelpout) but no trend in condition for the same site.Heavy MetalsDue to a change in methods for metal analysis (not Hg) in 2004, values between 2003 and2007 should be interpreted with care. From 2009 metals are analyzed at ITM, StockholmUniversity.The longer time series in guillemot egg and spring-caught herring from the southernBothnian Sea and southern Baltic Proper show significant decreases of mercury. Theherring site in the southern Bothnain Sea indicates a local Hg-source. The rest of the timeseries show varying concentrations over the study period, and even increasing trends in e.g.cod muscle and eelpout muscle from Väderöarna, but the concentrations are fairly lowcompared to measured concentrations in perch from fresh water and coastal sites. However,in most cases, these concentrations are above the newly suggested EU-target level of 20ng/g wet weight.Lead is generally decreasing over the study period (in time series of sufficient length),supposedly due to the elimination of lead in gasoline. Elevated lead concentrationsbetween 2003 and 2007 (e.g. Harufjärden) should be viewed with caution (see aboveregarding change in analysis methods).Cadmium concentrations show varying non-linear trends over the monitored period. It isworth noting that despite several measures taken to reduce discharges of cadmium,generally the most recent concentrations are similar to concentrations measured 30 yearsago in the longer time series.The reported nickel concentrations show no consistent decreasing trends. Some series beginwith two elevated values that exert a strong leverage effect on the regression line and maygive a false impression of decreasing trends. Chromium generally shows decreasing trends,possibly explained by a shift in analytical method. The essential trace metals, copper andzinc, show no consistent trends during the monitored period.
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| 39. |
- Björkman, Börje, 1956-, et al.
(author)
-
Arkiven på väg in i cyberspace?
- 1998
-
In: HumaNetten. - Växjö : Institutionen för humaniora. - 1403-2279. ; :3
-
Journal article (pop. science, debate, etc.)
|
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| 40. |
- Bondsman, Benjamin, et al.
(author)
-
Modal analysis of CLT beams: Measurements and predictive simulations
- 2022
-
In: Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems : Proceedings of The Eighth International Conference on Structural Engineering, Mechanics and Computation, 5-7 September 2022, Cape Town, South Africa - Proceedings of The Eighth International Conference on Structural Engineering, Mechanics and Computation, 5-7 September 2022, Cape Town, South Africa. - London : CRC Press. - 9781003348443 ; , s. 56-62
-
Conference paper (peer-reviewed)abstract
- Cross-laminated timber (CLT) as a prime example of an innovative product within the field of civil engineering has over the recent years attracted attention of the construction industry and engineers around the world. As a natural composite with different orientation of layers in addition to anisotropic properties of wood, CLT can be a challenging material in predictive numerical modelling. This is possibly due to uncertainty in the mechanical behaviour of the material owing to its growing conditions. In addition, timber structures are more sensitive to vibrations and structure-borne sound at low frequencies than conventional concrete based structures. Therefore, a thorough understanding of dynamic characteristics of CLT and accurate predictive models can enhance its potential in the construction industry. This work presents a numerical and an experimental modal analysis of CLT beams within a frequency range relevant for vibrations and structure-borne sound. In the experimental investigation, a series of CLT beams with dimensions 120 120 2000 [mm3], cut from a larger CLT plate, composed of two covering layers of Norway spruce and a mid-layer of Scots pine are studied. Resonant frequencies, bending and torsional modes are utilised for a thorough study of the beams. The results are presented in terms of statistical variation in experimental resonant frequencies. Furthermore, a numerical sensitivity study with respect to variation in the mechanical properties of CLT is presented.
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| 41. |
- Borg, Tessie, et al.
(author)
-
Diastereoselective Nucleophilic Addition to Aldehydes with Polar alpha- and alpha,beta-Substituents
- 2011
-
In: Advanced Synthesis and Catalysis. - : Wiley. - 1615-4150 .- 1615-4169. ; 353:11-12, s. 2022-2036
-
Journal article (peer-reviewed)abstract
- The stereoselectivities obtained in Lewis acid-promoted Mukaiyama aldol additions and Sakurai allylations of mono-, and syn- and anti-disubstituted aldehydes possessing various polar alpha- and beta-substituents under non-chelating conditions are presented. The stereochemical outcome in the nucleophilic addition to alpha-substituted aldehydes containing an alpha-benzyloxy, alpha-fluoro or alpha-sulfonamide substituent are accurately predicted by current stereoinduction models. In contrast, the selectivitites obtained from addition of sterically demanding nucleophiles to alpha-chloro-substituted aldehydes cannot be rationalized by the same models and an alternative is discussed. The stereochemichal outcome in the additions to alpha, beta-disubstituted aldehydes is more complex and cannot be predicted using current models.
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| 42. |
- Borg, Tessie, et al.
(author)
-
Mukaiyama aldol addition to α-chloro-substituted aldehydes. Origin of the unexpected syn selectivity.
- 2010
-
In: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; 46:8, s. 1281-1283
-
Journal article (peer-reviewed)abstract
- The addition of sterically demanding enolsilanes to alpha-chloro aldehydes results unexpectedly in preferential formation of the anti-PFA product (1,2-syn), while the addition of the corresponding boron enolate furnishes the expected polar Felkin-Anh product (1,2-anti). A stereoinduction model explaining these observations is proposed.
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| 43. |
- Cedersund, Gunnar, et al.
(author)
-
Model-Based Hypothesis Testing of Key Mechanisms in Initial Phase of Insulin Signaling
- 2008
-
In: PloS Computational Biology. - : Public Library of Science. - 1553-734X .- 1553-7358. ; 4:6
-
Journal article (peer-reviewed)abstract
- Type 2 diabetes is characterized by insulin resistance of target organs, which is due to impaired insulin signal transduction. The skeleton of signaling mediators that provide for normal insulin action has been established. However, the detailed kinetics, and their mechanistic generation, remain incompletely understood. We measured time-courses in primary human adipocytes for the short-term phosphorylation dynamics of the insulin receptor (IR) and the IR substrate-1 in response to a step increase in insulin concentration. Both proteins exhibited a rapid transient overshoot in tyrosine phosphorylation, reaching maximum within 1 min, followed by an intermediate steady-state level after approximately 10 min. We used model-based hypothesis testing to evaluate three mechanistic explanations for this behavior: (A) phosphorylation and dephosphorylation of IR at the plasma membrane only, (B) the additional possibility for IR endocytosis, (C) the alternative additional possibility of feedback signals to IR from downstream intermediates. We concluded that (A) is not a satisfactory explanation, that (B) may serve as an explanation only if both internalization, dephosphorylation, and subsequent recycling are permitted, and that (C) is acceptable. These mechanistic insights cannot be obtained by mere inspection of the datasets, and they are rejections and thus stronger and more final conclusions than ordinary model predictions.
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| 44. |
- Cronemyr, Peter, et al.
(author)
-
Process Management 1-2-3 : a maturity model and diagnostics tool
- 2013
-
In: Total Quality Management and Business Excellence. - : Routledge. - 1478-3363 .- 1478-3371. ; 24:7-8, s. 933-944
-
Journal article (peer-reviewed)abstract
- In this article, we provide an insight into Process Management that offers a simple hands-on method to improve Process Management. Organisations implementing ‘some modern’ management concept sometimes fail or do not achieve the expected results. From our own industrial experiences, we found that organisations implementing Process Management sometimes start off on a ‘too-advanced’ level without having fulfilled the necessary prerequisites. For that purpose, in this article, we present a Process Management maturity model developed in an environment of industrial and academic cooperation. In addition to the model, we present a diagnostics tool that has been developed together with several companies to be used by organisations to assess their current level of process maturity. By using this, it is the purpose that organisations could reduce their risk of starting off ‘too high’ and thus failing in their efforts.
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| 45. |
|
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| 46. |
- Danielsson, Anna, et al.
(author)
-
Attenuation of insulin-stimulated insulin receptor substrate-1 serine 307 phosphorylation in insulin resistance of type 2 diabetes
- 2005
-
In: Journal of biological chemistry. - 0021-9258 .- 1083-351X. ; 280:41, s. 34389-3492
-
Journal article (peer-reviewed)abstract
- Insulin resistance is a primary characteristic of type 2 diabetes and likely causally related to the pathogenesis of the disease. It is a result of defects in signal transduction from the cell surface receptor of insulin to target effects. We found that insulin-stimulated phosphorylation of serine 307 (corresponding to serine 302 in the murine sequence) in the immediate downstream mediator protein of the insulin receptor, insulin receptor substrate-1 (IRS1), is required for efficient insulin signaling and that this phosphorylation is attenuated in adipocytes from patients with type 2 diabetes. Inhibition of serine 307 phosphorylation by rapamycin mimicked type 2 diabetes and reduced the sensitivity of IRS1 tyrosine phosphorylation in response to insulin, while stimulation of the phosphorylation by okadaic acid, in cells from patients with type 2 diabetes, rescued cells from insulin resistance. EC50 for insulin-stimulated phosphorylation of serine 307 was about 0.2 nM with a t1/2 of about 2 min. The amount of IRS1 was similar in cells from non-diabetic and diabetic subjects. These findings identify a molecular mechanism for insulin resistance in non-selected patients with type 2 diabetes.
|
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| 47. |
- Danielsson, Anders, et al.
(author)
-
Development and optimization of a metabolomic method for analysis of adherent cell cultures
- 2010
-
In: Analytical Biochemistry. - : Elsevier BV. - 1096-0309 .- 0003-2697. ; 404:1, s. 30-39
-
Journal article (peer-reviewed)abstract
- In this investigation, a gas chromatography/mass spectrometry (GC/MS)-based metabolomic protocol for adherent cell cultures was developed using statistical design of experiments. Cell disruption, metabolite extraction, and the GC/MS settings were optimized aiming at a gentle, unbiased, sensitive, and high-throughput metabolomic protocol. Due to the heterogeneity of the metabolome and the inherent selectivity of all analytical techniques, development of unbiased protocols is highly complex. Changing one parameter of the protocol may change the response of many groups of metabolites. In this investigation, statistical design of experiments and multivariate analysis also allowed such interaction effects to be taken into account. The protocol was validated with respect to linear range, precision, and limit of detection in a clonal rat insulinoma cell line (INS-1 832/13). The protocol allowed high-throughput profiling of metabolites covering the major metabolic pathways. The majority of metabolites displayed a linear range from a single well in a 96-well plate up to a 10 cm culture dish. The method allowed a total of 47 analyses to be performed in 24 h. (C) 2010 Elsevier Inc. All rights reserved.
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| 48. |
- Danielsson, Anders, et al.
(author)
-
Development of a gas chromatography/mass spectrometry based metabolomics protocol by means of statistical experimental design
- 2012
-
In: Metabolomics. - : Springer Science and Business Media LLC. - 1573-3882 .- 1573-3890. ; 8:1, s. 50-63
-
Journal article (peer-reviewed)abstract
- Metabolomics is a growing research field where new protocols are rapidly developed and new applications discovered. Common applications include biomarker discovery and elucidation of drug metabolism. However, the development of such protocols rarely includes a systematic optimization followed by validation with real samples. Here a GC/MS-based protocol using methoximation followed by silylation with N-tert-butyldi-methylsilyl-N-methyltrifluoroacetamide (MTBSTFA) for analysis of blood plasma metabolites is thoroughly developed and optimized from derivatization to detection with statistical design of experiments (DOE). Validation was performed with blood plasma samples and proved the methodology to be efficient, rapid and reliable with a total of 51 analyses performed in 24 h, with linear responses, low detection limits and good precision. The obtained chromatograms were much cleaner, due to the absence of glucose overloading, and the data was found to drift less with MTBSTFA derivatisation than with MTBSTFA derivatisation.
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| 49. |
- Danielsson, Anna, et al.
(author)
-
Insulin resistance in human adipocytes occurs downstream of IRS1 after surgical cell isolation but at the level of phosphorylation of IRS1 in type 2 diabetes
- 2005
-
In: The FEBS Journal. - : Wiley. - 1742-464X .- 1742-4658. ; 272:1, s. 141-151
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Journal article (peer-reviewed)abstract
- Insulin resistance is a cardinal feature of type 2 diabetes and also a consequence of trauma such as surgery. Directly after surgery and cell isolation, adipocytes were insulin resistant, but this was reversed after overnight incubation in 10% CO2 at 37 °C. Tyrosine phosphorylation of the insulin receptor and insulin receptor substrate (IRS)1 was insulin sensitive, but protein kinase B (PKB) and downstream metabolic effects exhibited insulin resistance that was reversed by overnight incubation. MAP-kinases ERK1/2 and p38 were strongly phosphorylated after surgery, but was dephosphorylated during reversal of insulin resistance. Phosphorylation of MAP-kinase was not caused by collagenase treatment during cell isolation and was present also in tissue pieces that were not subjected to cell isolation procedures. The insulin resistance directly after surgery and cell isolation was different from insulin resistance of type 2 diabetes; adipocytes from patients with type 2 diabetes remained insulin resistant after overnight incubation. IRS1, PKB, and downstream metabolic effects, but not insulin-stimulated tyrosine phosphorylation of insulin receptor, exhibited insulin resistance. These findings suggest a new approach in the study of surgery-induced insulin resistance and indicate that human adipocytes should recover after surgical procedures for analysis of insulin signalling. Moreover, we pinpoint the signalling dysregulation in type 2 diabetes to be the insulin-stimulated phosphorylation of IRS1 in human adipocytes.
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- Danielsson, Anna, 1973-
(author)
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Insulin signalling in human adipocytes : mechanisms of insulin resistance in type 2 diabetes
- 2007
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Doctoral thesis (other academic/artistic)abstract
- Prevalensen av fetma ökar drastiskt i stora delar av världen och utgör en stor riskfaktor för att utveckla insulinresistens och typ 2 diabetes. Fettväven kan bli mycket stor om för mycket energi tas upp av kroppen. Vid extrem övervikt är fettväven i kroppen i ett stresstillstånd, vilket gör att risken för att utveckla metabola sjukdomar som t.ex. typ 2 diabetes ökar. Fett lagras i olika fettdepåer i kroppen. Inlagringen i djupare kroppsdelar, runt och i inre organ s.k. visceralt fett, skiljer sig från fettväven som lagras direkt under huden s.k. subkutant fett. Nyare rön visar att mer visceral fettväv ökar risken för att utveckla insulinresistens och typ 2 diabetes.Fettcellen är tillsammans med muskel- och leverceller de viktigaste för glukosmetabolismen. Fettcellen är en stor cell, som man lätt kan se med blotta ögat. Storleken på ellerna varierar dock kraftigt i en och samma fettvävnad. Upptag av glukos från maten vi äter regleras av hormonet insulin. Insulinresistens är ett tillstånd då cellerna svarar dåligt på insulin, vilket gör att glukoshalten i blodet ökar. Detta förekommer vid typ 2 diabetes, men även vid andra tillstånd där cellerna blir stressade, t.ex. kirurgiska ingrepp. Insulinsignaleringen i fettcellen är komplex och signalöverföringen inne i cellen sker främst via en kaskad av fosforyleringar, där olika proteiner i en signalkedja fosforyleras eller defosforyleras. Slutligen leder denna fosforyleringskaskad till insulinets sluteffekter som t.ex. upptag av glukos, proteinsyntes och celltillväxt. Efter att insulin bundit till och fosforylerat/aktiverat insulinreceptorn delas signalen upp inne i cellen i två huvudvägar; den metabola signalvägen och den mitogena signalvägen. Insulinreceptorsubstrat 1, IRS1, är ett stort protein som insulinreceptorn verkar direkt på. Fosforylering av aminosyran tyrosin på IRS1 är mycket viktigt för fortsatt insulinsignalering i fettcellen. IRS1 fosforyleras även på aminosyran serin som svar på bl.a. insulin. Serinfosforyleringen av IRS1 hämmar eller stimulerar insulinsignaleringen, ofta genom återkoppling av insulinsignalen.Syftet med den här avhandlingen är att beskriva möjliga cellulära mekanismer i insulinsignaleringen vid insulinresistens som resultat av kirurgisk stress eller vid typ 2 diabetes i fettceller från människa.Häri har upptaget av glukos analyserats och jämförts i fettceller från olika fettdepåer. Viscerala fettceller har högre basalt och insulinstimulerat glukosupptag och mer glucostransportörprotein än subkutana fettceller. Däremot är det ingen skillnad i insulinkänslighet angående glukosupptaget i de olika typerna av fettceller.Vidare fann vi att den kirurgiskt orsakade insulinresistensen hos subkutana fettceller från människa återgår till det normala efter övernattinkubering av cellerna i odlingsmedium. Insulinresistensen vid typ 2 diabetes är däremot permanent och har en annan mekanism än den reversibla, stress-relaterade insulinresistensen. Insulinresistansen vid typ 2 diabetes beror på att signalöverföringen mellan olika proteiner i cellen är defekt. Insulinreceptorns förmåga att fosforylera IRS1 på aminosyran tyrosin är nedsatt hos patienter med typ 2 diabetes. Fosforyleringen av IRS1 på serin 307 (i den humana sekvensen) ökar snabbt hos icke-diabetiska fettceller som svar på insulin. Denna serinfosforylering verkar behövas för att IRS1 effektivt ska tyrosinfosforyleras och därmed leda insulinsignalen vidare inne i cellen. Fosforyleringen av IRS1 på serin 307 är kraftigt nedsatt hos subkutana fettceller från patienter med typ 2 diabetes. Fosforyleringen av IRS1 på serin 312 är däremot liknande i fettceller från icke-diabetiker och diabetiker (Öst et.al. (2007) Faseb.J. doi: 10.1096/fj.07-8173com). Fosforyleringen av IRS1 på serin 312 är mest involverad i insulinsignaleringens negativa återkoppling. Fosforyleringen av serin 307 sker snabbt och vid låga insulinkoncentrationer, medan fosforyleringen på serin 312 sker först efter lång inkubering och vid höga insulinkoncentrationer.Detta är en ny mekanism på cellulär nivå som möjligen kan beskriva insulinresistansen i fettceller från människa. Tillsammans styrs återkopplingen via den stimulerande fosforyleringen (serin 307) eller den hämmande fosforyleringen (serin 312) och kontrollerar insulinsignaleringen i cellen. Fosforyleringarna sker möjligen via samma proteinkinas och/eller proteinfosfatas och kan bli mål för terapeutiska läkemedel mot typ 2 diabetes i framtiden.
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