| 1. |
- Aad, G., et al.
(författare)
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- 2011
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swepub:Mat__t (refereegranskat)
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| 2. |
- Wanhainen, Anders, et al.
(författare)
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The effect of ticagrelor on growth of small abdominal aortic aneurysms-a randomized controlled trial
- 2020
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Ingår i: Cardiovascular Research. - : Oxford University Press (OUP). - 0008-6363 .- 1755-3245. ; 116:2, s. 450-456
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To evaluate if ticagrelor, an effective platelet inhibitor without known non-responders, could inhibit growth of small abdominal aortic aneurysms (AAAs). Methods and results: In this multi-centre randomized controlled trial, double-blinded for ticagrelor and placebo, acetylic salicylic acid naive patients with AAA and with a maximum aortic diameter 35-49mm were included. The primary outcome was mean reduction in log-transformed AAA volume growth rate (%) measured with magnetic resonance imaging (MRI) at 12months compared with baseline. Secondary outcomes include AAA-diameter growth rate and intraluminal thrombus (ILT) volume enlargement rate. A total of 144 patients from eight Swedish centres were randomized (72 in each group). MRI AAA volume increase was 9.1% for the ticagrelor group and 7.5% for the placebo group (P=0.205) based on intention-to-treat analysis, and 8.5% vs. 7.4% in a per-protocol analysis (P=0.372). MRI diameter change was 2.5mm vs. 1.8mm (P=0.113), US diameter change 2.3mm vs. 2.2mm (P=0.778), and ILT volume change 12.9% vs. 10.4% (P=0.590). Conclusion: In this RCT, platelet inhibition with ticagrelor did not reduce growth of small AAAs. Whether the ILT has an important pathophysiological role for AAA growth cannot be determined based on this study due to the observed lack of thrombus modulating effect of ticagrelor.
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| 3. |
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| 4. |
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| 5. |
- Krmar, R T, et al.
(författare)
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Acute renal failure in dense deposit disease: complete recovery after combination therapy with immunosuppressant and plasma exchange.
- 2011
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Ingår i: Clinical Nephrology. - 0301-0430. ; 75:S1, s. 4-10
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Tidskriftsartikel (refereegranskat)abstract
- We describe the clinical course of a female adolescent who was followed because of isolated microhematuria and hypocomplementemia before admission to hospital with a sudden onset of acute renal failure. At presentation, she exhibited complement consumption through the complement alternative pathway (AP) while other serologic tests were negative. Renal biopsy revealed dense deposit disease (DDD) with a crescentic pattern. Intravenous methylprednisolone, followed by plasma exchange (PE), and intravenous cyclophosphamide pulses were started shortly after admission. C3NeF and anti-factor H antibody tests were negative. Serum factor H and I levels were normal as well as factor H activity. Screening for mutation in the factor H gene revealed the H402 allele variant. Clinical remission, defined as normalization in renal function and in the activity levels of the complement AP, was noted at one month post-presentation and throughout the follow-up. A repeat renal biopsy showed the disappearance of crescent formation, whereas electron microscopy revealed no regression in dense transformation of the lamina densa. In summary, our patient was successfully treated with immunosuppressant and PE. The absence of known factors associated with DDD suggests that, in this particular case, other regulatory mechanisms of complement AP might have been involved in the disease process.
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| 6. |
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| 7. |
- Nauert, A., et al.
(författare)
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Experimental analysis of flashback in lean premixed swirling flames: conditions close to flashback
- 2007
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Ingår i: Experiments in Fluids. - : Springer Science and Business Media LLC. - 1432-1114 .- 0723-4864. ; 43:1, s. 89-100
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Tidskriftsartikel (refereegranskat)abstract
- Swirling lean premixed flames are of practical relevance due to their potential for low nitric oxide (NOx) emissions. Unfortunately, these flames have various drawbacks. One critical attribute is the possibility for flashback of the reacting flow into the nozzle. Advanced numerical simulations should be able in the future to predict the transition from stable flames to flashback. For a better understanding of the process itself and for validation of numerical simulation a well-documented generic benchmark experiment is needed. This study presents a burner configuration that has already been studied extensively in the past. By minor geometrical adaptations, and via the possibility to vary the swirl intensity in a controlled way, the transition from stable flames to flashback is now accessible to detailed characterisation using advanced laser diagnostics. In a first part of this study the different states of the flame were classified. In the second part, both a stable and a precessing flame very close to flash back were compared in terms of flow and scalar field. The variation of the swirl intensity on the flame is discussed. Because the flame is strongly influenced by its inflow conditions additional velocity measurements inside the nozzle were carried out. This is of special importance for subsequent numerical simulations to match the experimental conditions. The quantitative investigation of the flame during flashback is subjected to consecutive experiments where planar laser diagnostics at high repetition rates will be exploited.
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| 8. |
- Nogenmyr, Karl-Johan, et al.
(författare)
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Large Eddy Simulation and Experiments of Stratified Lean Premixed Methane/Air Turbulent Flames
- 2007
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Ingår i: Proceedings of the Combustion Institute. - : Elsevier BV. - 1540-7489. ; 31:1, s. 1467-1475
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a joint large eddy simulation and laser diagnostic investigation of premixed turbulent low swirl flames. A lean premixed methane/air mixture, of the equivalence ratio 0.60-0.66, is injected from a 50 mm diameter low swirl burner to a low speed co-flowing air at room temperature and pressure. The level-set G-equation is employed to simulate the inner layer flame front. Flamelet chemistry is used to determine the flame properties in the reactive zones. Mixing and heat transfer in the post-flame zone down-stream are modeled using transport equations. In addition to large eddy simulation, simultaneous 2-D laser induced fluorescence of OH and 2-D particle image velocimetry are used to characterize the basic flame structure. Laser Doppler velocimetry is employed to further analyze the flow velocity along the central axis above the burner, and 2-D filtered Rayleigh scattering is used to measure the temperature field in the lower part of the flame. A bowl-shaped, highly wrinkled turbulent flame is stabilized at a position about one-half diameter above the burner. The flame consists of two distinct parts; around the burner axis, a premixed flame with uniform mixture fraction is stabilized in the low speed flow region induced by the inflow swirl; off the axis of the burner, a stratified lean premixed flame is found in the shear layer of the flow field. Flame holes (local extinction) owing to overly lean mixtures are observed in the off-axis lean stratified part of the flame. A unified level-set G-equation is developed to model the flame holes. The basic flow and flame structure from the model simulations are compared to the laser diagnostic measurements; the height of flame stabilization (lift-off height), the mean temperature profile, and the mean axial and radial velocity components together with rms velocity components are in fairly good agreement with measurement data. © 2006 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
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| 9. |
- Wanhainen, Anders, et al.
(författare)
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Outcome of the Swedish Nationwide Abdominal Aortic Aneurysm Screening Program
- 2016
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Ingår i: Circulation. - 0009-7322 .- 1524-4539. ; 134:16, s. 1141-1148
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Tidskriftsartikel (refereegranskat)abstract
- Background: A general abdominal aortic aneurysm (AAA) screening program, targeting 65-year-old men, has gradually been introduced in Sweden since 2006 and reached nationwide coverage in 2015. The aim of this study was to determine the outcome of this program. Methods: Data on the number of invited and examined men, screening-detected AAAs, AAAs operated on, and surgical outcome were retrieved from all 21 Swedish counties for the years 2006 through 2014. AAA-specific mortality data were retrieved from the Swedish Cause of Death Registry. A linear regression analysis was used to estimate the effect on AAA-specific mortality among all men 65 years of age for the observed time period. The long-term effects were projected by using a validated Markov model. Results: Of 302957 men aged 65 years invited, 84% attended. The prevalence of screening-detected AAA was 1.5%. After a mean of 4.5 years, 29% of patients with AAA had been operated on, with a 30-day mortality rate of 0.9% (1.3% after open repair and 0.3% after endovascular repair, P<0.001). The introduction of screening was associated with a significant reduction in AAA-specific mortality (mean, 4.0% per year of screening, P=0.020). The number needed to screen and the number needed to operate on to prevent 1 premature death were 667 and 1.5, respectively. With a total population of 9.5 million, the Swedish national AAA-screening program was predicted to annually prevent 90 premature deaths from AAA and to gain 577 quality-adjusted life-years. The incremental cost-efficiency ratio was estimated to be Euro7770 per quality-adjusted life-years. Conclusions: Screening 65-year-old men for AAA is an effective preventive health measure and is highly cost-effective in a contemporary setting. These findings confirm the results from earlier randomized controlled trials and model studies in a large population-based setting of the importance for future healthcare decision making.
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| 10. |
- Berrocal, E., et al.
(författare)
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Image transfer through the complex scattering turbid media
- 2006
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Ingår i: Laser Physics Letters. - : IOP Publishing. - 1612-2011 .- 1612-202X. ; 3:9, s. 464-467
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Tidskriftsartikel (refereegranskat)abstract
- Seeing through a turbid medium such as fog, mist or clouds is a fascinating idea that would find applications in a large range of fields from research to industry. The main difficulty of this challenging task is related to the complexity of the multiple of optical radiation propagated through an emsemble of scattering particles and/or droplets randomly distributed in a medium. To deal with this challenging problem to deal with a new Monte Carlo based method computational technique able to simulate image transfer through the complex inhomogenous turbid media. The model is able to identify the contribution of the scattering orders in the detected images for a particular medium. With the presented approach the simulation of laser propagation and image transfer of an object hidden within a turbid scattering medium has been performed. The results of simulation demonstrate a good agreement with the experimental results. The validation of the technique has been one by using several modeling samples of water polystyrenes spheres solutions.
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| 11. |
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| 12. |
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| 13. |
- Holland, Stephen T., et al.
(författare)
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GRB 090417B and its host galaxy : a step toward an understanding of optically dark gamma-ray bursts
- 2010
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 717:1, s. 223-234
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Tidskriftsartikel (refereegranskat)abstract
- GRB 090417B was an unusually long burst with a T-90 duration of at least 2130 s and a multi-peaked light curve at energies of 15-150 keV. It was optically dark and has been associated with a bright star-forming galaxy at a redshift of 0.345 that is broadly similar to the Milky Way. This is one of the few cases where a host galaxy has been clearly identified for a dark gamma-ray burst (GRB) and thus an ideal candidate for studying the origin of dark bursts. We find that the dark nature of GRB 090417B cannot be explained by high redshift, incomplete observations, or unusual physics in the production of the afterglow. Assuming the standard relativistic fireball model for the afterglow we find that the optical flux is at least 2.5 mag fainter than predicted by the X-ray flux. The Swift/XRT X-ray data are consistent with the afterglow being obscured by a dense, localized sheet of dust approximately 30-80 pc from the burst along the line of sight. Our results suggest that this dust sheet imparts an extinction of A(V) greater than or similar to 12 mag, which is sufficient to explain the missing optical flux. GRB 090417B is an example of a GRBs that is dark due to the localized dust structure in its host galaxy.
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| 14. |
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| 15. |
- Hultgren, R., et al.
(författare)
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Cost-effectiveness of targeted screening for abdominal aortic aneurysm in siblings
- 2019
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Ingår i: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 106:3, s. 206-216
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Tidskriftsartikel (refereegranskat)abstract
- Background: Population screening for abdominal aortic aneurysm (AAA) in 65‐year‐old men has been shown to be cost‐effective. A risk group with higher prevalence is siblings of patients with an AAA. This health economic model‐based study evaluated the potential cost‐effectiveness of targeted AAA screening of siblings.Methods: A Markov model validated against other screening programmes was used. Two methods of identifying siblings were analysed: direct questioning of patients with an AAA (method A), and employing a national multigeneration register (method B). The prevalence was based on observed ultrasound data on AAAs in siblings. Additional parameters were extracted from RCTs, vascular registers, literature and ongoing screening. The outcome was cost‐effectiveness, probability of cost‐effectiveness at different willingness‐to‐pay (WTP) thresholds, reduction in AAA death, quality‐adjusted life‐years (QALYs) gained and total costs on a national scale.Results_ Methods A and B were estimated to reduce mortality from AAA, at incremental cost‐effectiveness ratios of €7800 (95 per cent c.i. 4627 to 12 982) and €7666 (5000 to 13 373) per QALY respectively. The probability of cost‐effectiveness was 99 per cent at a WTP of €23 000. The absolute risk reduction in AAA deaths was five per 1000 invited. QALYs gained were 27 per 1000 invited. In a population of ten million, methods A and B were estimated to prevent 12 and 17 AAA deaths, among 2418 and 3572 siblings identified annually, at total costs of €499 500 and €728 700 respectively.Conclusion: The analysis indicates that aneurysm‐related mortality could be decreased cost‐effectively by applying a targeted screening method for siblings of patients with an AAA.
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| 16. |
- Hultgren, R, et al.
(författare)
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Long-Term Follow-Up of Men Invited to Participate in a Population-Based Abdominal Aortic Aneurysm Screening Program
- 2020
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Ingår i: Angiology. - : SAGE Publications. - 1940-1574 .- 0003-3197. ; 71:7, s. 641-649
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Tidskriftsartikel (refereegranskat)abstract
- A screening program for abdominal aortic aneurysm (AAA), inviting 65-year-old men, was started in Stockholm in 2010 (2.3 million inhabitants). The aim was to present a long-term follow-up of men participating in screening, as well as AAA repair and ruptures among nonparticipants. Demographics were collected for men with screening detected with AAA 2010 to 2016 (n = 672) and a control group with normal aortas at screening (controls, n = 237). Medical charts and regional Swedvasc (Swedish Vascular registry) data were analyzed for aortic repair for men born 1945 to 1951. Ultrasound maximum aortic diameter (AD) as well as Aortic Size Index (ASI) was recorded. Participation was 78% and prevalence of AAA was 1.2% (n = 672). Aortic repair rates correlated with high ASI and AD. During the study period, 22% of the AAA patients were treated with the elective repair; 35 men in surveillance died (5.2%), non-AAA-related causes (82.9%) dominated, followed by unknown causes among 4 (11.4%), and 2 (5.7%) possibly AAA-related deaths. Abdominal aortic aneurysm rupture rate was higher among nonparticipants (0.096% vs 0.0036%, P < .001). The low dropout rate confirms acceptability of follow-up after screening. The efficacy is shown by the much higher rupture rate among the nonparticipating men.
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| 17. |
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| 18. |
- Lindskog, Cecilia, et al.
(författare)
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The human cardiac and skeletal muscle proteomes defined by transcriptomics and antibody-based profiling
- 2015
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Ingår i: BMC Genomics. - : Springer Science and Business Media LLC. - 1471-2164. ; 16
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Tidskriftsartikel (refereegranskat)abstract
- Background: To understand cardiac and skeletal muscle function, it is important to define and explore their molecular constituents and also to identify similarities and differences in the gene expression in these two different striated muscle tissues. Here, we have investigated the genes and proteins with elevated expression in cardiac and skeletal muscle in relation to all other major human tissues and organs using a global transcriptomics analysis complemented with antibody-based profiling to localize the corresponding proteins on a single cell level. Results: Our study identified a comprehensive list of genes expressed in cardiac and skeletal muscle. The genes with elevated expression were further stratified according to their global expression pattern across the human body as well as their precise localization in the muscle tissues. The functions of the proteins encoded by the elevated genes are well in line with the physiological functions of cardiac and skeletal muscle, such as contraction, ion transport, regulation of membrane potential and actomyosin structure organization. A large fraction of the transcripts in both cardiac and skeletal muscle correspond to mitochondrial proteins involved in energy metabolism, which demonstrates the extreme specialization of these muscle tissues to provide energy for contraction. Conclusions: Our results provide a comprehensive list of genes and proteins elevated in striated muscles. A number of proteins not previously characterized in cardiac and skeletal muscle were identified and localized to specific cellular subcompartments. These proteins represent an interesting starting point for further functional analysis of their role in muscle biology and disease.
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| 19. |
- Linne, A, et al.
(författare)
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Abdominal aortic aneurysm screening attendance: Effect of removing the examination fee
- 2018
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Ingår i: Journal of medical screening. - : SAGE Publications. - 1475-5793 .- 0969-1413. ; 25:4, s. 223-224
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Tidskriftsartikel (refereegranskat)abstract
- The organized population-based screening programme for abdominal aortic aneurysm in Stockholm, Sweden, started in 2010. An examination fee was initially charged, but later removed because of a policy change. We examined the effect on screening attendance of removing the fee. Methods The periods before and after removing the examination fee were compared with regard to screening attendance, overall, by municipality and by district. Results Screening attendance was 79.2% in the period with an examination fee and 79.9% in the period without an examination fee (p = 0.1787), with no significant change in screening attendance between the periods. Conclusions Although removing examination fees has been shown to have a positive impact on attendance in other screening programmes, we did not find this association in our study.
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| 20. |
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| 21. |
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| 22. |
- Linne, A., et al.
(författare)
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Low Post-operative Mortality after Surgery on Patients with Screening-detected Abdominal Aortic Aneurysms : A Swedvasc Registry Study
- 2014
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1078-5884 .- 1532-2165. ; 48:6, s. 649-656
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Screening for abdominal aortic aneurysms (AAAs) substantially reduces aneurysm-related mortality in men and is increasing worldwide. This cohort study compares post-operative mortality and complications in men with screening-detected vs. non-screening-detected AAAs. Methods: Data were extracted from the Swedish National Registry for Vascular Surgery (Swedvasc) for all screening-detected men treated for AAA (n = 350) and age-matched controls treated for non-screening-detected AAA (n = 350). Results: There were no differences in baseline characteristics besides age, which was lower in the screening-detected group than in the non-screening-detected group (median 66 vs. 68, p < .001). Open repair was used more frequently than endovascular aortic repair (EVAR) in patients with screening-detected AAAs than in nonscreening-detected controls (56% vs. 45% p = .005). No differences in major post-operative complications at 30 days were observed between the groups. In patients treated with open repair there were no differences in 30-day, 90-day or 1-year mortality in screening-detected patients compared to non-screening-detected controls (1.0% vs. 3.2% p = .25, 2.1% vs. 4.5% p = .23, 4.1% vs. 5.8% p = .61). None of the patients treated with EVAR in either group died within 30 days. The 90-day mortality after EVAR was lower in patients with screening-detected AAA than in those with non-screening-detected AAAs (0.0% vs. 3.1%, p = .04). No difference in the 1-year mortality was detected in the EVAR-patients between the two groups (1.4% vs. 4.7%, p = .12). Conclusions: The contemporary post-operative mortality after AAA surgery was low in this national audit of patients with screening-detected AAAs and age-matched controls. Patients with screening-detected AAAs have the same frequency of complications at 30 days as patients with non-screening-detected AAA. This study gives further support to national screening programs for the detection of AAA in men.
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| 23. |
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| 24. |
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| 25. |
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| 26. |
- Merlo, Juan, et al.
(författare)
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Survival after initial hospitalisation for heart failure: a multilevel analysis of patients in Swedish acute care hospitals
- 2001
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Ingår i: Journal of Epidemiology and Community Health. - : BMJ. - 1470-2738 .- 0143-005X. ; 55:5, s. 323-329
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Tidskriftsartikel (refereegranskat)abstract
- STUDY OBJECTIVE: Although national variation in short-term prognosis (that is, 30 day mortality) after a patients first hospitalisation for heart failure may depend on individual differences between patients, dissimilarities in hospital practices may also influence prognosis. This study, therefore, sought to disentangle patient determinants from institutional factors that might explain such variation.DESIGN: A multilevel logistic regression modelling was performed with patients (1st level) nested in hospitals (2nd level). Institutional effects (that is, 2nd level variance and intra-hospital correlation) were calculated unadjusted and adjusted for specific patient (that is, age and previous diseases) and institutional (that is, size of hospital) characteristics. Patients were followed up until death or 30 days from hospital admission.SETTING: Hospitals in Sweden.PATIENTS: The study identified all the 20 420 men and 17 923 women (ages 65 to 85) admitted to the 90 acute care hospitals in Sweden during the period 1992-1995 for their first hospitalisation attributable to heart failure.MAIN RESULTS: Patient age and previous diseases (particularly senile dementia) were major determinants of impaired prognosis. Institutional factors explained only 1.6 and 2.3 of the total variation in 30 day mortality in men and women, respectively. These modest institutional effects remained after adjusting for patient age and previous diseases, but were in part explained by hospital size.CONCLUSIONS: National variation in short-term prognosis after an initial hospitalisation for heart failure was mainly explained by differences between patients, with hospital factors playing a minor part. Of the latter, hospital size seemed to emerge as one determinant (that is, the greater the number of patients, the better the individual prognosis).
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| 27. |
- Mills, James A., et al.
(författare)
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Archiving Primary Data : Solutions for Long-Term Studies
- 2015
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Ingår i: Trends in Ecology & Evolution. - : Elsevier BV. - 0169-5347 .- 1872-8383. ; 30:10, s. 581-589
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Tidskriftsartikel (refereegranskat)abstract
- The recent trend for journals to require open access to primary data included in publications has been embraced by many biologists, but has caused apprehension amongst researchers engaged in long-term ecological and evolutionary studies. A worldwide survey of 73 principal investigators (PIs) with long-term studies revealed positive attitudes towards sharing data with the agreement or involvement of the PI, and 93% of PIs have historically shared data. Only 8% were in favor of uncontrolled, open access to primary data while 63% expressed serious concern. We present here their viewpoint on an issue that can have non-trivial scientific consequences. We discuss potential costs of public data archiving and provide possible solutions to meet the needs of journals and researchers.
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| 28. |
- Molin, M., et al.
(författare)
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Case management at an outpatient unit for severe and enduring eating disorder patients at Stockholm Centre for Eating Disorders : a study protocol
- 2016
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Ingår i: International Journal of Eating Disorders. - London, United Kingdom : BioMed Central. - 0276-3478 .- 1098-108X .- 2050-2974. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Patients with severe and enduring eating disorders (SEED) are seriously ill and have a low quality of life. Case management (CM), originally developed for adult patients with severe mental disabilities, has been shown to enhance social functioning and improve quality of life, while reducing the number and length of hospitalizations. In 2014, a special unit based on CM, for patients with SEED (the Eira unit) was started at Stockholm Centre for Eating Disorders, Sweden.Method/Design: This study aims to investigate if CM can improve SEED patients' quality of life, and reduce their eating disorder symptoms as well as their health care consumption. Methods for data collection are a semi-structured diagnostic interview, self-report questionnaires, and a qualitative interview. The diagnostic interview and the self-report assessments will be done at start of treatment and at follow-ups after 1, 2, and 3years. The qualitative interview will be conducted 1 year after start of treatment. The study is approved by the ethical review board in Stockholm in compliance with the Helsinki Declaration.Discussion: CM is a possible new contribution to the treatment methods for SEED. It does not aim at remission, but rather to accept life as it is, and to enhance quality of life in the presence of the ED. This study will investigate the potential benefits of this novel intervention in a special unit for SEED patients.Trail Registration: Clinicaltrials.gov Id: NCT02897622.
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| 29. |
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| 30. |
- Omrane, Alaa, et al.
(författare)
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Simultaneous 2D flow velocity and gas temperature measurements using thermographic phosphors
- 2008
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Ingår i: Applied Physics B. - : Springer Science and Business Media LLC. - 0946-2171 .- 1432-0649. ; 92:1, s. 99-102
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Tidskriftsartikel (refereegranskat)abstract
- In this paper a new approach for simultaneous 2D velocity and temperature measurements using phosphoric particles is presented. The phosphoric particles respond to the temperature changes in the flow while acting as tracers for velocity mapping. The temperature sensitive particles were seeded into a heated flow and were excited by a pulsed UV laser. The subsequent red shifted emission was detected and analyzed to infer temperature using calibration procedures for lifetime and emission spectra against temperature. The diameter of the temperature sensitive particles, usually in the range of 1-10 mu m, makes them useful for velocity measurements using particle image velocimetry (PIV). As such, simultaneous measurement of temperature and flow velocity of a gaseous flow were performed and presented.
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| 31. |
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| 32. |
- Zhang, C., et al.
(författare)
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Measuring fundamental properties in operating solid oxide electrochemical cells by using in situ X-ray photoelectron spectroscopy
- 2010
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Ingår i: Nature Materials. - : Springer Science and Business Media LLC. - 1476-4660 .- 1476-1122. ; 9:11, s. 944-949
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Tidskriftsartikel (refereegranskat)abstract
- Photoelectron spectroscopic measurements have the potential to provide detailed mechanistic insight by resolving chemical states, electrochemically active regions and local potentials or potential losses in operating solid oxide electrochemical cells (SOCs), such as fuel cells. However, high-vacuum requirements have limited X-ray photoelectron spectroscopy (XPS) analysis of electrochemical cells to ex situ investigations. Using a combination of ambient-pressure XPS and CeO2-x/YSZ/Pt single-chamber cells, we carry out in situ spectroscopy to probe oxidation states of all exposed surfaces in operational SOCs at 750 °C in 1 mbar reactant gases H2 and H 2O. Kinetic energy shifts of core-level photoelectron spectra provide a direct measure of the local surface potentials and a basis for calculating local overpotentials across exposed interfaces. The mixed ionic/electronic conducting CeO2-x electrodes undergo Ce3+/Ce4+ oxidation-reduction changes with applied bias. The simultaneous measurements of local surface Ce oxidation states and electric potentials reveal the active ceria regions during H2 electro-oxidation and H2O electrolysis. The active regions extend ∼150 μm from the current collectors and are not limited by the three-phase-boundary interfaces associated with other SOC materials. The persistence of the Ce3+/Ce 4+ shifts in the ∼150 μm active region suggests that the surface reaction kinetics and lateral electron transport on the thin ceria electrodes are co-limiting processes.
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