| 1. |
- Bergström, Göran, 1964, et al.
(författare)
-
Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population
- 2021
-
Ingår i: Circulation. - Philadelphia : American Heart Association. - 0009-7322 .- 1524-4539. ; 144:12, s. 916-929
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population.Methods: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data.Results: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population.Conclusions: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.
|
|
| 2. |
- Bergström, Göran, et al.
(författare)
-
Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population
- 2021
-
Ingår i: Circulation. - : Wolters Kluwer. - 0009-7322 .- 1524-4539. ; 144:12, s. 916-929
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population.Methods: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data.Results: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population.Conclusions: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.
|
|
| 3. |
- Wassélius, Johan, et al.
(författare)
-
Treatment of mesenteric vein thrombosis with transjugular mechanical thrombectomy and subsequent simultaneous arterial and venous thrombolysis
- 2014
-
Ingår i: Journal of Vascular Surgery: Venous and Lymphatic Disorders. - : Elsevier BV. - 2213-333X. ; 2:3, s. 3-320
-
Tidskriftsartikel (refereegranskat)abstract
- Mesenteric vein thrombosis may induce intestinal ischemia and gangrene. In severe cases, it is necessary to restore venous outflow from the small intestine rapidly. We describe a severe case of mesenteric vein thrombosis that was resolved successfully by mechanical thrombectomy from a transjugular approach followed by selective simultaneous venous and arterial thrombolysis via the superior mesenteric vein and artery. In conclusion, the transjugular intrahepatic portosystemic approach was a feasible and safe access for mechanical thrombectomy and thrombolysis of the mesenteric vein in our patient.
|
|
| 4. |
- Ahlström, Anders, 1973-
(författare)
-
Aerolastic simulation of wind turbine dynamics
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The work in this thesis deals with the development of an aeroelastic simulation tool for horizontal axis wind turbine applications. Horizontal axis wind turbines can experience significant time varying aerodynamic loads, potentially causing adverse effects on structures, mechanical components, and power production. The needs for computational and experimental procedures for investigating aeroelastic stability and dynamic response have increased as wind turbines become lighter and more flexible. A finite element model for simulation of the dynamic response of horizontal axis wind turbines has been developed. The developed model uses the commercial finite element system MSC.Marc, focused on nonlinear design and analysis, to predict the structural response. The aerodynamic model, used to transform the wind flow field to loads on the blades, is a Blade-Element/Momentum model. The aerodynamic code is developed by The Swedish Defence Research Agency (FOI, previously named FFA) and is a state-of-the-art code incorporating a number of extensions to the Blade-Element/Momentum formulation. The software SOSIS-W, developed by Teknikgruppen AB was used to generate wind time series for modelling different wind conditions. The method is general, and different configurations of the structural model and various type of wind conditions can be simulated. The model is primarily intended for use as a research tool when influences of specific dynamic effects are investigated. Verification results are presented and discussed for an extensively tested Danwin 180 kW stall-controlled wind turbine. Code predictions of mechanical loads, fatigue and spectral properties, obtained at different conditions, have been compared with measurements. A comparison is also made between measured and calculated loads for the Tjæreborg 2 MW wind turbine during emergency braking of the rotor. The simulated results correspond well to measured data.
|
|
| 5. |
- Ahlström, Anders, et al.
(författare)
-
The dominant role of semi-arid ecosystems in the trend and variability of the land CO2 sink
- 2015
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 348:6237, s. 895-899
-
Tidskriftsartikel (refereegranskat)abstract
- The growth rate of atmospheric carbon dioxide (CO2) concentrations since industrialization is characterized by large interannual variability, mostly resulting from variability in CO2 uptake by terrestrial ecosystems (typically termed carbon sink). However, the contributions of regional ecosystems to that variability are not well known. Using an ensemble of ecosystem and land-surface models and an empirical observation-based product of global gross primary production, we show that the mean sink, trend, and interannual variability in CO2 uptake by terrestrial ecosystems are dominated by distinct biogeographic regions. Whereas the mean sink is dominated by highly productive lands (mainly tropical forests), the trend and interannual variability of the sink are dominated by semi-arid ecosystems whose carbon balance is strongly associated with circulation-driven variations in both precipitation and temperature.
|
|
| 6. |
|
|
| 7. |
- Ahlström, Martin
(författare)
-
Stand development and growth in uneven-aged Norway spruce and multi-layered Scots pine forests in boreal Sweden
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The use of the selection system has always been a marginal part of Swedish forestry, and so has research about the system under Swedish conditions. However, the interest in Sweden for uneven-aged forest management has increased because of a rising concern for the ecological and aesthetical consequences from use of the dominating rotation forests system, which creates even-aged forest and has clear-cutting as primary harvesting method. In this thesis I have studied the possibilities and limitations of the selection system in Swedish boreal forests. Stand development, ingrowth and volume increment has been studied in both Norway spruce (Picea abies (L.) H. Karst.), and Scots pine (Pinus sylvestris L.) forests. My studies of uneven-aged Norway spruce show that 1) these forests have the capacity to spontaneously create and maintain an uneven-aged stand structure, 2) there is a positive relation between standing volume and volume increment, and 3) there is no clear relation between the level of ingrowth and stand density. My studies of multi-layered Scots pine forests show that 1) a multi-layered stand structure is more likely the result of size stratification and not of continuous ingrowth, 2) There is positive relation between standing volume and volume increment, and 3) that a low stand density is seems required for ingrowth to occur on a sustainable level. The results imply that for boreal Norway spruce forests, a high standing volume would be recommended when the selection system is applied, whereas for boreal Scots pine forest, uneven-aged management should be motivated by other values than stem production, e.g. aesthetical or ecological.
|
|
| 8. |
- Bökberg, Christina, et al.
(författare)
-
Care and Service at Home for People With Dementia in Europe
- 2015
-
Ingår i: Abstractbook Nordic Conference on Advances in Health Care Sciences Research. ; , s. 22-22
-
Konferensbidrag (refereegranskat)abstract
- Purpose: To describe available and utilized professional care and service at home for people with dementia, from diagnosis to end-of-life stage, in eight European countries. Design: A descriptive cross-country design concerning eight European countries as a part of the European research project, RightTimePlaceCare (RTPC).Methods: The research team in each country used a mapping system to collect countryspecific information on a general level concerning dementia care and service system. The mapping system consisted of fifty types of care and service activities. Sixteen of the fifty predefined activities concerning professional care and service at home were selected for this study and subdivided into three categories, following the stages of dementia.Results: Availability was reported to be higher than utilization and the results indicated more similarities than differences among the eight countries involved. Even though there were several available activities of Basic care and services and Health care interventions they were utilized by few in most countries. Furthermore, Specialized care and services for people with dementia were sparsely available and even more sparsely utilized in the participating countries.Conclusions: The results indicated that people with dementia in Europe received professional care and service on a general, basic level but seldom received care and service adjusted to their specific needs.Clinical Relevance: This study highlights available and utilized types of care and service activities enabling nurses to develop individually adjusted care plans for people with dementia during the progress of the disease. Knowledge of care and services in other countries provides nurses with an important tool for the improvement of dementia care. However assessing the quality of care requires an indication of informal care provision in different countries.
|
|
| 9. |
- Bökberg, Christina, et al.
(författare)
-
Care and Service at Home for Persons With Dementia in Europe
- 2015
-
Ingår i: Journal of Nursing Scholarship. - Hoboken : Wiley-Blackwell Publishing Inc.. - 1527-6546 .- 1547-5069. ; 47:5, s. 407-416
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe available and utilized formal care and service at home for persons with dementia, from diagnosis to end-of-life stage, in eight European countries.Design: A descriptive cross-country design concerning eight European countries as a part of the European research project RightTimePlaceCare.Methods: The research team in each country used a mapping system to collect country-specific information concerning dementia care and service system. The mapping system consists of 50 types of care and service activities. Sixteen of the 50 predefined activities concerning care and service at home were selected for this study and subdivided into three categories, following the stages of dementia.Findings: Availability was reported to be higher than utilization, and the findings indicated more similarities than differences among the eight countries involved. Even though there were several available activities of "basic care and services" and "healthcare interventions," they were utilized by few in most countries. Furthermore, "specialized dementia care and services" were sparsely available and even more sparsely utilized in the participating countries.Conclusions: The findings indicated that persons with dementia in Europe received formal care and service on a general, basic level but seldom adjusted to their specific needs.Clinical Relevance: This study describes the gap between service provision and utilization enabling nurses to develop individually adjusted care plans for persons with dementia during the progress of the disease. The findings do not include matters of quality of care or how to best organize effective care and services. However, the activities of care and services presented here should shed light on what room there is for improvement when it comes to enabling persons with dementia to go on living at home. © 2015 Sigma Theta Tau International.
|
|
| 10. |
- Citterio, Michele, et al.
(författare)
-
Automatic weather stations for basic and applied glaciological research
- 2015
-
Ingår i: Geological Survey of Denmark and Greenland Bulletin. - 1811-4598 .- 1604-8156. ; 33, s. 69-72
-
Tidskriftsartikel (refereegranskat)abstract
- Since the early 1980s, the Geological Survey of Denmark and Greenland (GEUS) glaciology group has developed automatic weather stations (AWSs) and operated them on the Greenland ice sheet and on local glaciers to support glaciological research and monitoring projects (e.g. Olesen & Braithwaite 1989; Ahlstrøm et al. 2008). GEUS has also operated AWSs in connection with consultancy services in relation to mining and hydropower pre-feasibility studies (Colgan et al. 2015). Over the years, the design of the AWS has evolved, partly due to technological advances and partly due to lessons learned in the field. At the same time, we have kept the initial goal in focus: long-term, year-round accurate recording of ice ablation, snow depth and the physical parameters that determine the energy budget of glacierised surfaces. GEUS has an extensive record operating AWSs in the harsh Arctic environment of the diverse ablation areas of the Greenland ice sheet, glaciers and ice caps [...].The GEUS AWS model in use now is a reliable tool that is adapted to the environmental and logistical conditions of polar regions. It has a proven record of more than 150 stationyears of deployment in Greenland since its introduction in 2007–2008, and a success rate of c. 90% defined as the fraction of months with more than 80% valid air-temperature measurements over the total deployment time of the 25 stations in the field. The rest of this paper focuses on the technical aspects of the GEUS AWS, and provides an overview of its design and capabilities.
|
|
