| 1. |
- Abdo, A. A., et al.
(author)
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Fermi Large Area Telescope Search for Photon Lines from 30 to 200 GeV and Dark Matter Implications
- 2010
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 104:9, s. 091302-
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Journal article (peer-reviewed)abstract
- Dark matter (DM) particle annihilation or decay can produce monochromatic gamma rays readily distinguishable from astrophysical sources. gamma- ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a gamma-ray line analysis, and integrated over most of the sky. We obtain gamma-ray line flux upper limits in the range 0.6-4.5 x 10(-9) cm(-2) s(-1), and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed.
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| 2. |
- Ackermann, M., et al.
(author)
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GeV GAMMA-RAY FLUX UPPER LIMITS FROM CLUSTERS OF GALAXIES
- 2010
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In: ASTROPHYS J LETT. - 2041-8205. ; 717:1, s. l71-L78
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Journal article (peer-reviewed)abstract
- The detection of diffuse radio emission associated with clusters of galaxies indicates populations of relativistic leptons infusing the intracluster medium (ICM). Those electrons and positrons are either injected into and accelerated directly in the ICM, or produced as secondary pairs by cosmic-ray ions scattering on ambient protons. Radiation mechanisms involving the energetic leptons together with the decay of neutral pions produced by hadronic interactions have the potential to produce abundant GeV photons. Here, we report on the search for GeV emission from clusters of galaxies using data collected by the Large Area Telescope on the Fermi Gamma-ray Space Telescope from 2008 August to 2010 February. Thirty-three galaxy clusters have been selected according to their proximity and high mass, X-ray flux and temperature, and indications of non-thermal activity for this study. We report upper limits on the photon flux in the range 0.2-100 GeV toward a sample of observed clusters (typical values (1-5) x 10(-9) photon cm(-2) s(-1)) considering both point-like and spatially resolved models for the high-energy emission and discuss how these results constrain the characteristics of energetic leptons and hadrons, and magnetic fields in the ICM. The volume-averaged relativistic-hadron-to-thermal energy density ratio is found to be <5%-10% in several clusters.
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| 3. |
- Koch Frisén, Angelica, 1970-, et al.
(author)
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Analysis of outcome of Lichtenstein groin hernia repair by surgeons in training versus a specialized surgeon
- 2011
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In: Hernia. - : Springer. - 1265-4906 .- 1248-9204. ; 15:3, s. 281-288
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Journal article (peer-reviewed)abstract
- Purpose: Groin hernia repair is a common procedure in general surgery, and is taught to and performed by surgeons early in their training. The aim of this observational study was to compare hernia repair performance and results of surgical trainees with those of a specialized surgeon. The further aim sought to identify what factors may influence short and long-term outcome, and areas for improvement in surgical training. Methods: A non-randomized parallel cohort study was designed to compare a specialized surgeon with surgical trainees, performing the Lichtenstein repair in adult males. Two hundred repairs were included, of which 96 were performed by surgical trainees. Patient characteristics, surgical experience, and operative data including duration of procedural parts and surgical complexity were noted at surgery. Postoperative complications, recurrence, chronic pain and residual symptoms were assessed at longterm follow-up after a median of 34.5 months. Results: Surgical trainees had longer overall operative time consume, with an unproportionally longer time for mobilising the sac and cord. They perceived exposure and mobilisation as more difficult than the specialist, and also a greater demand on own experience during surgery. The trainee repairs had a higher rate of postoperative complications (14.7% versus 5.0%) but recurrence rate was the same as for specialist repairs. At long-term follow-up, specialist repairs had a higher symptom burden and more chronic pain. Conclusions: Comparison of a specialized surgeon to surgical trainees in performance and outcome for inguinal hernia surgery shows it was more efficient, but not necessarily better to let a specialized surgeon perform the repairs. The better long-term outcome for surgical trainees stands in contrast to the prejudice that it is better to have an experienced surgeon to perform standard procedures. It seems likely that targeted training in dissection and mobilisation could decrease level of perceived complexity and shorten operative time consume for surgical trainees. We believe that adequately supervised hernia surgery should remain as a part of the surgical training.
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| 4. |
- Nordanstig, Joakim, et al.
(author)
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Mortality with Paclitaxel-Coated Devices in Peripheral Artery Disease.
- 2020
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In: The New England journal of medicine. - : Massachusetts Medical Society. - 1533-4406 .- 0028-4793. ; 383, s. 2538-46
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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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| 5. |
- Starck, Joachim, et al.
(author)
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A significant correlation between body surface area and infrarenal aortic diameter is detected in a large screening population with possibly clinical implications
- 2019
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In: International Angiology. - 1827-1839. ; 38:5, s. 395-401
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Journal article (peer-reviewed)abstract
- BACKGROUND: Screening for abdominal aortic aneurysm (AAA) in elderly men reduces aneurysm related mortality. AAA is commonly defined as an infrarenal aortic diameter (IAD) of ≥30 mm, which is based on the definition of an arterial aneurysm as a focal dilation of 150% or more compared to the expected diameter of about 20 mm. The IAD has been shown to correlate to body surface area (BSA). The aim of this study was to investigate the possibility to use an individualized AAA-criteria by using a BSA-based model to refine the screening for AAA. METHODS: We conducted an observational single center cohort study of 25 236 65-year old men invited to AAA screening in Malmö, Sweden 2010-2015. Out of the 19 738 (78.5%) attendees, 14 846 (58.8%) completed a health questionnaire including height, weight and smoking habits. Linear regression analysis was performed between BSA and IAD, taking smoking habits into account. This regression was used to calculate the predicted IAD for each individual according to their BSA. RESULTS: There was a significant correlation between BSA and aortic diameter, rho =0.26 (95% CI: 0.25, 0.28). AAA defined as an IAD≥30 mm was found in 226 men (1.5%) whereas AAA defined as ≥150% larger IAD than predicted according to the individual BSA was found in 299 men (1.9%), a relative difference in AAA detection rate of more than 30% (P<0.001). CONCLUSIONS: We have found a statistically significant correlation between BSA and IAD in a homogenous screening population that could have clinical implications. In men with low BSA, IAD <30 mm might still be ≥150% larger than predicted according to BSA, whereas in men with high BSA, IAD≥30 mm might not be ≥150% larger than predicted. Further follow-up of these subjects is planned to investigate if the first group have an "aneurysm-in-formation," challenging the diagnostic criteria for AAA.
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| 6. |
- Starck, Joachim, et al.
(author)
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Abdominal aortic aneurysm growth rates are not correlated to body surface area in screened men
- 2023
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In: International Angiology. - : EDIZIONI MINERVA MEDICA. - 1827-1839 .- 0392-9590. ; 42:1, s. 65-72
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Journal article (peer-reviewed)abstract
- BACKGROUND: Screening for abdominal aortic aneurysm (AAA) in 65-year-old males reduces aneurysm related mortality. Infrarenal aortic diameter (IAD) has been shown to correlate to body surface area (BSA) which could influence diagnostic criteria for AAA. This study investigates whether AAA growth rates are also dependent on BSA, as that might have potential effects on surveillance of small AAAs.METHODS: We conducted a retrospective, single center cohort study of 301 men with screening detected AAA between 2010-2017 with surveillance to 2021. AAA growth rates were analyzed in relation to the subject's BSA, smoking habits, and diabetic disease using a linear mixed-effects model. All men were offered smoking cessation program, optimized medical treatment, and advice on physical activity.RESULTS: The screening program included 28,784 men. Of the 22,819 (79%) attending the examinations, 374 men (1.6%) were found to have an AAA out of which 301 men had undergone two or more examinations during surveillance and were included with a median follow-up of 1846 days (IQR: 1 399). Mean unadjusted AAA growth rate was 1.60 mm/year (95% CI: 1.41-1.80). Diabetes mellitus had a statistically significant negative impact, smoking had a statistically significant positive impact on AAA growth rates whereas no correlation between AAA growth rate and BSA could be found.CONCLUSIONS: Body surface area could not be found to have a statistically significant correlation to AAA growth rates. The impact of smoking and diabetes on AAA growth rates remains similar to previously reported.
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