| 1. |
- Joelsson-Alm, Eva, et al.
(författare)
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Perioperative bladder distension : a prospective study
- 2009
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Ingår i: Scandinavian Journal of Urology and Nephrology. - 0036-5599 .- 1651-2065. - 0036-5599 ; 43:1, s. 58-62
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. Postoperative urinary retention and bladder distension are frequent complications of surgery. The aim of this study was to determine the incidence of perioperative bladder distension in a surgical setting and to identify predisposing factors among patients undergoing common general and orthopaedic procedures. Material and methods. This was a prospective observational study of 147 adult patients admitted to orthopaedic and surgical departments. Bladder volumes were measured with an ultrasound scanner on three occasions: after emptying the bladder before being transported to the operating theatre, and then immediately before and after surgery. Results. Thirty-three patients (22%) developed bladder distension (500 ml), eight preoperatively and 25 postoperatively. A total of 21 patients (14%) had a bladder volume 300 ml immediately before surgery. Orthopaedic patients were more likely to develop preoperative bladder distension than surgical patients and had significantly higher postvoid residual volumes. In the binary logistic regression analysis age, gender and time of anaesthesia could not predict bladder distension. Patients undergoing orthopaedic surgical procedures, however, were prone to bladder distension (odds ratio 6.87, 95% confidence interval 1.76 to 26.79, p=0.006). Conclusions. This study shows that orthopaedic surgical patients are more prone to bladder distension perioperatively. The conventional method of encouraging patients to void at the ward before being transported to the operating theatre does not necessarily mean an empty bladder at the start of the operation.
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| 2. |
- Pazooki, David, 1958, et al.
(författare)
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Continent cutaneous urinary diversion in patients with spinal cord injury.
- 2006
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Ingår i: Spinal cord : the official journal of the International Medical Society of Paraplegia. - : Springer Science and Business Media LLC. - 1362-4393. ; 44:1, s. 19-23
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Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Retrospective study. OBJECTIVE: To examine the functional results and effect on quality of life of continent cutaneous urinary diversion in spinal cord injured patients. SETTING: Department of Urology, Sahlgrenska University Hospital, Göteborg, Sweden. SUBJECTS: A total of 10 patients with spinal cord injury (SCI). METHOD: The patients were operated on with an ileal reservoir (Kock reservoir or T-pouch), Cr-EDTA clearance was determined preoperatively and at follow-up. The patients answered a questionnaire concerning reservoir function, various activities and quality of life. The patient charts were reviewed. RESULTS: One patient died of pulmonary embolism 3 years after surgery. Two patients were reoperated on for reservoir perforation. All patients were satisfied/very satisfied with their reservoirs. Half of them reported improved ability to perform various activities. Eight out of nine patients reported improved quality of life. CONCLUSION: For a selected group of patients with SCI, continent cutaneous urinary diversion provides successful outcome with improved quality of life.
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| 3. |
- Pazooki, David, 1958, et al.
(författare)
-
Continent cutaneous urinary diversion is still a valid alternative after cystectomy for bladder carcinoma.
- 2005
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Ingår i: Scand J Urol Nephrol. - : Informa UK Limited. ; 39:6, s. 468-473
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Tidskriftsartikel (refereegranskat)abstract
- Objective. We compared patient opinions concerning reservoir/bladder function as well as quality of life (QOL) after cystectomy for bladder carcinoma and continent cutaneous urinary diversion or orthotopic bladder reconstruction. Material and methods. Fifteen patients with Kock reservoirs (11 females, 4 males) and 11 men with orthotopic bladders answered the European Organization for Research and Treatment of Cancer quality-of-life questionnaire-C30 as well as specially constructed questions concerning reservoir/bladder function. The glomerular filtration rate (GFR) was determined using Cr-EDTA or iohexol clearance. Results. Functioning and global health/QOL scales did not differ between the two groups of operated patients or between diverted patients and gender- and age-matched groups from the general population. The majority of the patients were satisfied/very satisfied with their diversion but more patients were troubled by leakage in the orthotopic bladder group than in the Kock reservoir group. The GFR was similar in the two groups. Conclusion. Continent cutaneous urinary diversion is associated with fewer leakage problems than orthotopic bladder reconstruction after cystectomy for bladder carcinoma.
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| 4. |
- Carlsson, Christer, et al.
(författare)
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Consensus in distributed soft environments
- 1992
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Ingår i: European Journal of Operational Research. - : Elsevier. - 0377-2217 .- 1872-6860. ; 61:1-2, s. 165-185
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Tidskriftsartikel (refereegranskat)abstract
- This paper studies the problem of formalizing consensus reaching within a set of decision makers trying to find and agree upon a mutual decision. Decision makers produce their individual rankings, using their own pet decision schemas. Thus consensus reaching relies only on the aggregation of individual decisions rather than on individual decision procedures. The aggregation of the individual rankings is supported by an advising monitor which tries to contract the decision makers into a mutual decision through soft enforcement. Convergence to consensus then depends upon the decision makers' willingness to compromise. We use a topological approach to consensus where we can measure distances between decision makers. Within the approach we can also model the trade-off between a degree of consensus and a strength of majority.
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| 5. |
- Demker, Marie, 1960, et al.
(författare)
-
Förfinar arbetet mot rasism
- 2015
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Ingår i: Göteborgs-Posten. - 1103-9345. ; :17 juni 2015
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 6. |
- Elgåker, Hanna, et al.
(författare)
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Horse Keeping in Urban and Peri-Urban Areas: New Conditions for Physical Planning in Sweden
- 2010
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Ingår i: Geografisk Tidsskrift-Danish Journal of Geography. - : Informa UK Limited. - 0016-7223 .- 1903-2471. ; 110, s. 81-98
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Tidskriftsartikel (refereegranskat)abstract
- An increasing number of land use conflicts involving planning practice, equine activities and businesses and neighbouring landowners and residents have occurred in Swedish peri-urban areas. In a case study the disturbances and benefits arising from horses experienced by residents in two different areas of Sweden were investigated, together with a study of the attitudes of local planners to horse keeping near residential areas and subsequent policy documents. The results from the study found few conflicts between residents and horse keeping but revealed diverging practice and policy between municipalities, which may create a legal insecurity for the involved stakeholders. The results were mirrored in the broader perspective of spatial planning facing new challenges in the wake of the urban-rural diffusion. This was obtained by means of current planning theory discourse in examining the effects of set-back distance from rural contexts when applied in urban areas. The study illustrated a planning problem where the planning tools for managing this issue has been built on the urban- rural dichotomy providing unclear planning practice and policy in a peri-urban context. The result may be used to elucidate the character of this issue in the search for suitable planning tools in peri urban areas. Keywords Equine activity, land use, comprehensive planning, conflict, peri-urban
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| 7. |
- Elgåker, Hanna, et al.
(författare)
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Horse riding posing challenges to the Swedish Right of Public Access
- 2012
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Ingår i: Land Use Policy. - : Elsevier BV. - 0264-8377 .- 1873-5754. ; 29, s. 274-293
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Tidskriftsartikel (refereegranskat)abstract
- Increasing numbers of horses are being kept for sports and leisure purposes in peri-urban areas throughout the Western world. This expansion of the equestrian sector represents a multifunctional transition, with new production of rural goods and services and increasing influence on land use. In Sweden, the number of horses has increased from 70,000 to approximately 300,000 over the last 30 years. This increase is putting pressure on the traditional Right of Public Access, an old custom allowing the public to walk, cycle or ride on private or state-owned property. This paper analyses multifunctional land use in peri-urban areas in order to provide a deeper understanding of the potential conflicts arising due to the expanding equine sector and to assess how these can affect the Swedish right of public access and spatial planning. A survey of horse riders and landowners in three peri-urban regions of Sweden revealed that these groups differ in their attitudes towards the Right of Public Access. The data also showed that the expanding equine sector is generating new demands on rural areas and there are questions regarding how the current system of open accessibility can meet the increasing market for equestrian leisure activities. The main conclusion is that there seems to be a strong need for intervention and deliberate creation of new ways of handling the accessibility question, where both a bottom-up and top-down approach may be useful
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| 8. |
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| 9. |
- Eriksson, Hanna, et al.
(författare)
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Low level of education is associated with later stage at diagnosis and reduced survival in cutaneous malignant melanoma : A nationwide population-based study in Sweden
- 2013
-
Ingår i: European Journal of Cancer. - Oxford : Elsevier. - 0959-8049 .- 1879-0852. ; 49:12, s. 2705-2716
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:A worse outcome has been reported for cutaneous malignant melanoma (CMM) patients with low socioeconomic status. We have investigated the association between level of education, clinical stage at diagnosis (stage at diagnosis) and CMM-specific survival in Sweden.METHODS:We identified 27,235 patients from the Swedish Melanoma Register diagnosed with a primary invasive CMM between 1990 and 2007 and linked data to nationwide, population-based, health and census registers with a follow-up to 2010.RESULTS:The odds ratio (OR) of higher disease stage at diagnosis was significantly increased in lower education groups (OR stage II versus I=1.6; 95% confidence interval (CI)=1.5-1.7. OR stage III-IV versus I=2.3; 95% CI=1.8-2.9). The risk of dying of CMM, was significantly increased in patients with low (hazard ratio (HR) low versus high=2.02; 95% CI=1.80-2.26; p<0.0001) and intermediate (HR intermediate versus high=1.35; 95% CI=1.20-1.51; p<0.0001) level of education. After adjustment for age, gender, stage at diagnosis and other known prognostic factors, the HRs remained significant for low versus high (HR=1.13; 95% CI=1.01-1.27; p=0.04) but not for intermediate versus high (HR=1.11; 95% CI=0.99-1.24; p=0.08) education. The HR associated with low level of education was significantly higher among female patients, patients <55years, patients with truncal tumours and during the first 5years after diagnosis.CONCLUSION:Lower level of education is associated with reduced CMM-specific survival, which may at least partially be attributed to a more advanced stage at diagnosis. These results emphasise the need for improved early detection strategies.
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| 10. |
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| 11. |
- Joelsson-Alm, Eva, et al.
(författare)
-
Perioperative bladder distension : a prospective study
- 2009
-
Ingår i: Scandinavian Journal of Urology and Nephrology. - : Informa Healthcare. - 0036-5599 .- 2168-1813 .- 1651-2065. ; 43:1, s. 58-62
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. Postoperative urinary retention and bladder distension are frequent complications of surgery. The aim of this study was to determine the incidence of perioperative bladder distension in a surgical setting and to identify predisposing factors among patients undergoing common general and orthopaedic procedures. Material and methods. This was a prospective observational study of 147 adult patients admitted to orthopaedic and surgical departments. Bladder volumes were measured with an ultrasound scanner on three occasions: after emptying the bladder before being transported to the operating theatre, and then immediately before and after surgery. Results. Thirty-three patients (22%) developed bladder distension (500 ml), eight preoperatively and 25 postoperatively. A total of 21 patients (14%) had a bladder volume 300 ml immediately before surgery. Orthopaedic patients were more likely to develop preoperative bladder distension than surgical patients and had significantly higher postvoid residual volumes. In the binary logistic regression analysis age, gender and time of anaesthesia could not predict bladder distension. Patients undergoing orthopaedic surgical procedures, however, were prone to bladder distension (odds ratio 6.87, 95% confidence interval 1.76 to 26.79, p=0.006). Conclusions. This study shows that orthopaedic surgical patients are more prone to bladder distension perioperatively. The conventional method of encouraging patients to void at the ward before being transported to the operating theatre does not necessarily mean an empty bladder at the start of the operation.
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| 12. |
- Karlsson, Margareta, 1942-
(författare)
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DNA ploidy, proliferation markers and prognosis in malignant melanoma
- 1995
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Malignant melanoma is a serious disease when metastases occur. It is therefore important to investigate possible tools for prediction to the outcome of the disease. In the present investigation 265 patients with cutaneous malignant melanoma and uveal melanoma was investigated with flow cytometry.In 82 patients with stage Ill cutaneous melanoma we found that the DNA ploidy and S-phase fraction on the primacy tumours and the time to the first metastases predicted the post-recurrence survival. Patients with diploid melanoma cells, low S-phase fraction and a long recurrence free interval had a rather favourable prognosis despite presence of regional metastases. In 55 subjects a significantly higher frequency of aneuploidy was found in metastases compared to the primary tumour of the same patients, suggesting a higher growth potential in metastases.A high S-phase fraction measured on the last histologically metastases before chemotherapy treatment was associated with an objective response and a longer survival in 87 patients with disseminated melanoma. The anatomical location of the metastases also predicted objective response, and together with a high S-phase fraction, a large number of metastatic sites and objective response were associated with survival.DNA ploidy together with histopathologic type and tumour size could predict the survival in 96 patients with uveal melanoma. A small, diploid tumour of spindle-cell type gave a significantly longer survival than a large, aneuploid tumour of epithelioid-cell type. In univariate statistical analysis the S-phase fraction predicted survival, but did not remain as a prognostic factor after adjustments for ploidy, histologic type and tumoursize. DNA ploidy and S-phase fraction were correlated with well-known histopathologic features. The proliferation marker Ki-67 was correlated with well-known histopathological features and associated with survival in 79 patients. This was not the case with the proliferation marker PCNA. Patients with uveal melanomas containing a high percentage of Ki-67 positive nuclei had a significant shorter survival than those with a low percentage.
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| 13. |
- Lindholm, Beata, et al.
(författare)
-
Cognitive and psychiatric symptoms are associated with walking difficulties in mild Parkinson’s disease
- 2020
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Ingår i: - : Wiley. ; , s. 549-549
-
Konferensbidrag (refereegranskat)abstract
- Objective: To investigate the association of different aspects of cognitive impairment, depression and anxiety with walking difficulties in daily life in persons with mild PD.Background: Walking difficulties in daily life are common among persons with Parkinson’s disease (PD) and may cause falls and near falls, limitations in activity, restrictions in participation and decrease in quality of life. Motor symptoms are often cited as a major reason for these difficulties while the association with cognitive and psychiatric symptoms is still poorly explored.Methods: The study included cross-sectional data from 73 persons with PD that visited a neurology outpatient clinic during 2012-2017. Mean (SD) age was 69 (8.9) years, mean (SD) disease duration was 8 (4.3) years and mean (SD) “on” phase motor symptoms (Unified PD Rating Scale, UPDRS, part III) and cognition (Mini Mental State Examination, MMSE) were 16.4 (9.9) and 27.3 (2.6), respectively. Walking difficulties in daily life (the dependent variable) was investigated with the generic Walk-12 (Walk-12G). Multiple linear regression analysis (controlling for age and motor symptoms) included the following independent variables: cognition (MMSE), memory (Alzheimer's Disease Assessment Scale, ADAS, cognitive subscale), cognitive perception speed (A Quick Test of Cognitive Speed, AQT, part I-III) frontal lobe/executive impairment (Frontal Assessment Battery, FAB) and depression and anxiety (Hospital Anxiety and Depression Scale, HADS). Results: The median Walk-12G scores was 11.5 (q1-q3, 5.5−25.5). Four significant independent variables were identified explaining 15.5% of the variance in the Walk-12G score. The factor with the strongest association with walking difficulties in daily life was cognitive perception speed (AQT part I) (explaining 4.9%) closed followed by anxiety (4.9%), cognitive perception speed (AQT part II) (3%) and frontal lobe/executive impairment (2.7%). Conclusion: Cognitive and psychiatric symptoms are associated with walking difficulties in persons with mild PD. Targeting cognitive perception speed, anxiety and frontal lobe/executive impairments in PD rehabilitation may help improve walking ability in daily life.
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| 14. |
- Lindholm, Christer, et al.
(författare)
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Invasive cutaneous malignant melanoma in Sweden, 1990-1999. A prospective, population-based study of survival and prognostic factors.
- 2004
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Ingår i: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 101:9, s. 2067-78
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The objective of the current study was to compile prospective, population-based data on cutaneous invasive melanomas in Sweden during the period from 1990 to 1999, to describe and analyze survival data and prognostic factors, and to make comparisons with previously published Swedish and international data. METHODS: Twelve thousand five hundred thirty-three patients, which included 97% of all registered melanomas in Sweden, were included and described. Among these, 9515 patients with clinical Stage I and II melanoma were included in an analysis of survival and in a univariate analysis, and 6191 patients were included in a multivariate analysis of prognostic factors. RESULTS: There was no significant change in melanoma incidence during 1990-1999. Favorable prognostic factors were found, especially in younger and female patients, resulting in a relative 5-year survival rate of 91.5%. In the multivariate analysis, significant factors that had a negative effect on survival were Clark level of invasion, Breslow thickness, ulceration, older patient age, trunk location, greatest tumor dimension, nodular histogenetic type, and male gender. CONCLUSIONS: During the period from 1990 to 1999, the 5-year survival of patients with malignant melanoma in Sweden was better compared with the previously reported rates in published, population-based studies from Sweden, probably as a result of better secondary prevention due to better knowledge and awareness by both patients and the medical profession. The more favorable prognostic factors and the change in melanoma location found in younger patients, compared with earlier reports, may reflect changes in clothing as well as tanning habits; however, a decrease also was found in Clark Level II and thin melanomas for the same patient group. The authors concluded that further improvements can be achieved with better access to health care and with the use of early melanoma detection campaigns.
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| 15. |
- Lindholm, Christina, et al.
(författare)
-
Sårbehandling. Reviderad 2013
- 2013
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Ingår i: Vårdhandboken. - Stockholm : Stockholms läns landsting.
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 16. |
- Lindholm, Per, et al.
(författare)
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Contact conditions in a cam and roller contact
- 2001
-
Ingår i: Proceedings of World Tribology Congress WT2001. - Wien : Österreichische Tribologishe Gesellshaft. - 390165707X
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 17. |
- Lyth, Johan, 1980-
(författare)
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Clinical-epidemiological studies on cutaneous malignant melanoma : A register approach
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The incidence of cutaneous malignant melanoma (CMM) is steadily increasing. Most of the patients have thin CMM with a good prognosis and a 5-year survival of about 90%. The prognosis is highly related to tumour thickness and clinical stage at diagnosis. Effective systemic treatment for patients with metastatic disease has only recently been available. This thesis aims to increase knowledge of trends in tumour thickness, prognostic factors, socioeconomic differences and medical costs in patients with CMM.The population-based Swedish melanoma register is the main source of data in all papers in the thesis. Papers I-III include patients from all of Sweden while paper IV is delimited to the County of Östergötland. Cox regression and logistic regression are the main multivariable methods used. Paper IV is focused on stage-specific costs of CMM by comparing direct healthcare costs to a general population.For men, there has been a shift over time towards thinner tumours at diagnosis accompanied by an improved survival. Women are still diagnosed with considerably thinner tumours and they experience a better survival than men. Tumour ulceration, tumour thickness and Clark’s level of invasion all showed significant independent long-term prognostic information in T1 CMMs. By combining these factors, three distinct prognostic subgroups were identified. Lower level of education was associated with reduced CMM-specific survival, which may at least partially be attributed to a more advanced stage at diagnosis. The direct healthcare costs for CMM patients were significantly higher than for the general population, independent of clinical stage. CMM patients diagnosed in clinical stage III-IV were associated with particularly high costs.Even though the survival among Swedish patients with CMM is among the highest in the world and still seems to improve, the results of this thesis emphasise the need of improved early detection strategies. This may be of particular concern in men, older women, and groups with a low level of education. The results also imply that the costs for the management of CMM patients may be reduced if early detection efforts are successful and lead to a more favourable stage distribution. The finding of a better risk stratification of thin CMMs may help to improve the management of this large patient group.
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| 18. |
- Lyth, Johan, 1980-, et al.
(författare)
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Stage-specific direct healthcare costs in patients with cutaneous malignant melanoma
- 2016
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Ingår i: Journal of the European Academy of Dermatology and Venereology. - : Wiley. - 0926-9959 .- 1468-3083. ; 30:5, s. 789-793
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Tidskriftsartikel (refereegranskat)abstract
- Background Clinical stage at diagnosis is a strong prognostic factor for death in cutaneous malignant melanoma (CMM), with worse prognosis at higher stages. However, few studies have investigated how direct healthcare cost per patient varies with clinical stage.Objective The aim of this study was to determine the stage-specific direct healthcare costs for CMM patients compared to the healthcare costs in the general population in the County of Östergötland, Sweden.Methods CMM patients in the County of Östergötland diagnosed 2005-2012 were identified from the Swedish cancer registry. Information on clinical stage was collected from the Swedish Melanoma Register (SMR) and cost data from the Cost per Patient database (CPP) for 1 075 CMM patients in Östergötland. CPP contains costs associated with all healthcare contacts per patient including inpatient, outpatient, and primary care. The CMM-related costs were defined as the difference in mean healthcare costs between CMM patients and general population.Results The first year after CMM diagnosis, the average healthcare costs for CMM patients was 2.8 times higher than in the general population. The healthcare cost ratio varied from 2.0 (stage I) to 10.1 (stage IV) and the CMM-related costs per patient-year varied from €2 670 (stage I) to €29 291 (stage IV). The mean healthcare costs decreased over time but remained significantly higher than in the general population for all clinical stages. During the first year after diagnosis, patients in clinical stage III-IV (7% of CMM patients) accounted for 27% of the total CMM-related healthcare costs.Conclusions The direct healthcare costs for CMM patients were significantly higher than in the general population independent of clinical stage. CMM patients diagnosed in clinical stage III-IV were associated with particularly high costs and the healthcare system may save resources by finding CMM patients in earlier stages.
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| 19. |
- Lörstad, Daniel, et al.
(författare)
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Experimental and LES investigations of a SGT-800 burner in a combustion rig
- 2010
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Ingår i: Proceedings of ASME, GT2010-22688. - 9780791843970 ; Volume 2: Combustion, Fuels and Emissions, Parts A and B, s. 549-561
-
Konferensbidrag (refereegranskat)abstract
- The Siemens gas turbine SGT-800 has an annular combustor and 30 dry low emission burners. In order to further reduce the emission levels and to obtain improved understanding of the flow and associated flame dynamics, single burner rig tests have been performed. The laboratory measurements are complemented by Large Eddy Simulation (LES) to analyze the effect on the flame dynamics due to the transient fuel distribution and mixing process in the burner. The study includes both atmospheric and high pressure conditions. The computational model was developed jointly by Siemens Industrial Turbomachinery AB (SIT) and FOI. It is based on a finite rate chemistry LES model using a Partially Stirred Reactor (PaSR) turbulence chemistry interaction model and a two-step CH4 /air mechanism developed by FOI. The results are compared to measurements performed jointly by SIT and Lund Institute of Technology. The experimental data includes wall temperature, pressure fluctuations, light intensity variation and simultaneous Planar Laser Induced Fluorescence of OH and acetone. The study is further complemented by Reynolds Averaged Navier-Stokes (RANS) calculations of the fuel concentration field evaluated to laser measurements in a water rig using the same burner configuration. Different burner fuel distributions are examined and the corresponding influence on the downstream mixing, fuel distribution and flame dynamics are studied. The results indicate that the fuel distribution upstream the flame, the detailed modeling of the fuel supply manifold, including the specification of numerical boundary conditions, and the flow in the fuel and air supply pipes, have significant influence on the flame dynamics. This is proven by the successful combustion LES of an unstable flame that experiences high flame dynamics and that a modification of the boundary conditions alters the dynamics resulting in a more stable flame. This is well in accordance with the experimental data and previous experience at SIT. The modal structures caused by the interaction between the flow, acoustics and flame dynamics are analyzed using the Proper Orthogonal Decomposition (POD) technique. The dominating modes in general originate from the burner mixing tube air-fuel-mass flow-interaction and flame-combustion chamber interaction.
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| 20. |
- Lörstad, Daniel, et al.
(författare)
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Measurements and LES of a SGT-800 Burner in a Combustion Rig
- 2012
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Ingår i: ASME Turbo Expo 2012, paper GT2012-69936. - 9780791844687 ; Volume 2: Combustion, Fuels and Emissions, Parts A and B, s. 1427-1438
-
Konferensbidrag (refereegranskat)abstract
- The Siemens gas turbine SGT-800 is the largest industrial gas turbine produced by Siemens Industrial Turbomachinery (SIT) offering a dry low emission (DLE) capability below 15 ppm NOx. It has a very high reliability using an annular combustor system with passive damping and 30 DLE burners. To obtain a greater understanding of the mixing process and the flame dynamics and in order to further reduce the emission levels, single burner rig tests have been performed. The laboratory measurements are complemented by Large Eddy Simulation (LES) and Reynolds Averaged Navier-Stokes (RANS) simulations to further investigate the transient fuel distribution and subsequent flame behavior. The measurements were performed jointly by SIT and Lund University using the SIT single burner combustion rig, where the square chamber allows great optical access in the flame region. The experimental data includes wall temperature, pressure fluctuations, light intensity variation and simultaneous Planar Laser Induced Fluorescence of OH and acetone. This investigation is complemented using fuel concentration field laser measurements of the fuel distribution upstream of the flame region in SIT water rig, using a burner partly made of Plexiglas to allow for optical access. The LES model was developed jointly by SIT and FOI. The LES computations were performed using a combustion code developed from the OpenFOAM library utilizing the mixed subgrid flow model, complemented with a subgrid wall model. The reacting flow was simulated using a Finite Rate Chemistry (FRC) combustion model based on the Partially Stirred Reactor (PaSR) model. For this study, a two-step global/reduced methane-air reaction mechanism was employed to describe the combustion chemistry. The RANS simulations were performed with ANSYS Fluent, using the k-ε Realizable eddy viscosity turbulence model in combination with the Fluent partially premixed combustion model. This model is a combination of the Zimont flamelet progress variable model and a Probability Density Function based non-premixed combustion model. The investigation includes a detailed evaluation of the numerical results compared to the measurement data. The numerical model includes the upstream air supply and fuel line systems up to well-defined constrictions to ensure appropriate acoustic inlet conditions. The measurements reveal large fluctuations in the flame region, which has been investigated using LES.
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| 21. |
- Möller, Torgil, et al.
(författare)
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Radiotherapy techniques in current use in Sweden.
- 2003
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Ingår i: Acta Oncologica. - : Informa UK Limited. - 1651-226X .- 0284-186X. ; 42:5-6, s. 376-386
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Tidskriftsartikel (refereegranskat)abstract
- A systematic assessment of radiotherapy for cancer was conducted by The Swedish Council on Technology Assessment in Health Care (SBU) in 2001. The assessment included a review of radiotherapy techniques in current use in Sweden. The following conclusions were drawn: Radiotherapy demands adequate knowledge of diagnostic methods, anatomy, cancer biology and of the physical and biological properties of ionizing radiation. Well-functioning teamwork on the part of the oncologist, medical physicist and oncology nurse is important.Radiotherapy has a high degree of technical sophistication, including the use of computers, which necessitates expert technical support.Technical development is rapid, and since the previous report, multileaf collimators and electronic portal imaging have been introduced in the clinical routine.The use of brachytherapy for treatment of non-gynaecological malignancies is rapidly increasing.The need for quality assurance in all steps of the radiotherapy procedure is stressed. A critical review of the literature on intraoperative radiotherapy is also included as an Appendix.
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| 22. |
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| 23. |
- van Leeuwen, Wessel M. A., et al.
(författare)
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Physiological and autonomic stress responses after prolonged sleep restriction and subsequent recovery sleep in healthy young men
- 2018
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Ingår i: Sleep and Biological Rhythms. - : Springer Science and Business Media LLC. - 1446-9235 .- 1479-8425. ; 16:1, s. 45-54
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Tidskriftsartikel (refereegranskat)abstract
- PurposeSleep restriction is increasingly common and associated with the development of health problems. We investigated how the neuroendocrine stress systems respond to prolonged sleep restriction and subsequent recovery sleep in healthy young men.MethodsAfter two baseline (BL) nights of 8 h time in bed (TIB), TIB was restricted to 4 h per night for five nights (sleep restriction, SR, n = 15), followed by three recovery nights (REC) of 8 h TIB, representing a busy workweek and a recovery weekend. The control group (n = 8) had 8 h TIB throughout the experiment. A variety of autonomic cardiovascular parameters, together with salivary neuropeptide Y (NPY) and cortisol levels, were assessed.ResultsIn the control group, none of the parameters changed. In the experimental group, heart rate increased from 60 ± 1.8 beats per minute (bpm) at BL, to 63 ± 1.1 bpm after SR and further to 65 ± 1.8 bpm after REC. In addition, whole day low-frequency to-high frequency (LF/HF) power ratio of heart rate variability increased from 4.6 ± 0.4 at BL to 6.0 ± 0.6 after SR. Other parameters, including salivary NPY and cortisol levels, remained unaffected.ConclusionsIncreased heart rate and LF/HF power ratio are early signs of an increased sympathetic activity after prolonged sleep restriction. To reliably interpret the clinical significance of these early signs of physiological stress, a follow-up study would be needed to evaluate if the stress responses escalate and lead to more unfavourable reactions, such as elevated blood pressure and a subsequent elevated risk for cardiovascular health problems.
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