University of Alberta

About: University of Alberta is a education organization based out in Edmonton, Alberta, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 65403 authors who have published 154847 publications receiving 5358338 citations. The organization is also known as: Ualberta & UAlberta.

Intense High-Energy Proton Beams from Petawatt-Laser Irradiation of Solids

Abstract: An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2). Up to 48 J ( 12%) of the laser energy is transferred to 2x10(13) protons of energy >10 MeV. The energy spectrum exhibits a sharp high-energy cutoff as high as 58 MeV on the axis of the beam which decreases in energy with increasing off axis angle. Proton induced nuclear processes have been observed and used to characterize the beam.

Interventions for preventing falls in elderly people

Abstract: BACKGROUND: Approximately 30 per cent of people over 65 years of age and living in the community fall each year; the number is higher in institutions Although less than one fall in 10 results in a fracture, a fifth of fall incidents require medical attention OBJECTIVES: To assess the effects of interventions designed to reduce the incidence of falls in elderly people (living in the community, or in institutional or hospital care) SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (January 2003), Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2003), MEDLINE (1966 to February 2003), EMBASE (1988 to 2003 Week 19), CINAHL (1982 to April 2003), The National Research Register, Issue 2, 2003, Current Controlled Trials (wwwcontrolled-trialscom accessed 11 July 2003) and reference lists of articles No language restrictions were applied Further trials were identified by contact with researchers in the field SELECTION CRITERIA: Randomised trials of interventions designed to minimise the effect of, or exposure to, risk factors for falling in elderly people Main outcomes of interest were the number of fallers, or falls Trials reporting only intermediate outcomes were excluded DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data Data were pooled using the fixed effect model where appropriate MAIN RESULTS: Sixty two trials involving 21,668 people were includedInterventions likely to be beneficial:Multidisciplinary, multifactorial, health/environmental risk factor screening/intervention programmes in the community both for an unselected population of older people (4 trials, 1651 participants, pooled RR 073, 95%CI 063 to 085), and for older people with a history of falling or selected because of known risk factors (5 trials, 1176 participants, pooled RR 086, 95%CI 076 to 098), and in residential care facilities (1 trial, 439 participants, cluster-adjusted incidence rate ratio 060, 95%CI 050 to 073) A programme of muscle strengthening and balance retraining, individually prescribed at home by a trained health professional (3 trials, 566 participants, pooled relative risk (RR) 080, 95% confidence interval (95%CI) 066 to 098) Home hazard assessment and modification that is professionally prescribed for older people with a history of falling (3 trials, 374 participants, RR 066, 95% CI 054 to 081) Withdrawal of psychotropic medication (1 trial, 93 participants, relative hazard 034, 95%CI 016 to 074) Cardiac pacing for fallers with cardioinhibitory carotid sinus hypersensitivity (1 trial, 175 participants, WMD -520, 95%CI -940 to -100) A 15 week Tai Chi group exercise intervention (1 trial, 200 participants, risk ratio 051, 95%CI 036 to 073) Interventions of unknown effectiveness:Group-delivered exercise interventions (9 trials, 1387 participants) Individual lower limb strength training (1 trial, 222 participants) Nutritional supplementation (1 trial, 46 participants) Vitamin D supplementation, with or without calcium (3 trials, 461 participants) Home hazard modification in association with advice on optimising medication (1 trial, 658 participants), or in association with an education package on exercise and reducing fall risk (1 trial, 3182 participants) Pharmacological therapy (raubasine-dihydroergocristine, 1 trial, 95 participants) Interventions using a cognitive/behavioural approach alone (2 trials, 145 participants) Home hazard modification for older people without a history of falling (1 trial, 530 participants) Hormone replacement therapy (1 trial, 116 participants) Correction of visual deficiency (1 trial, 276 participants)Interventions unlikely to be beneficial:Brisk walking in women with an upper limb fracture in the previous two years (1 trial, 165 participants) AUTHORS' CONCLUSIONS: Interventions to prevent falls that are likely to be effective are now available; less is known about their effectiveness in preventing fall-related injuries Costs per fall prevented have been established for four of the interventions and careful economic modelling in the context of the local healthcare system is important Some potential interventions are of unknown effectiveness and further research is indicated Language: en

Human TH17 lymphocytes promote blood-brain barrier disruption and central nervous system inflammation.

Abstract: T(H)17 lymphocytes appear to be essential in the pathogenesis of numerous inflammatory diseases. We demonstrate here the expression of IL-17 and IL-22 receptors on blood-brain barrier endothelial cells (BBB-ECs) in multiple sclerosis lesions, and show that IL-17 and IL-22 disrupt BBB tight junctions in vitro and in vivo. Furthermore, T(H)17 lymphocytes transmigrate efficiently across BBB-ECs, highly express granzyme B, kill human neurons and promote central nervous system inflammation through CD4+ lymphocyte recruitment.

Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector

Abstract: We report on results of an all-sky search for high-energy neutrino events interacting within the IceCube neutrino detector conducted between May 2010 and May 2012. The search follows up on the previous detection of two PeV neutrino events, with improved sensitivity and extended energy coverage down to about 30 TeV. Twenty-six additional events were observed, substantially more than expected from atmospheric backgrounds. Combined, both searches reject a purely atmospheric origin for the 28 events at the 4 sigma level. These 28 events, which include the highest energy neutrinos ever observed, have flavors, directions, and energies inconsistent with those expected from the atmospheric muon and neutrino backgrounds. These properties are, however, consistent with generic predictions for an additional component of extraterrestrial origin.

Mobile genetic elements: the agents of open source evolution.

Abstract: Horizontal genomics is a new field in prokaryotic biology that is focused on the analysis of DNA sequences in prokaryotic chromosomes that seem to have originated from other prokaryotes or eukaryotes. However, it is equally important to understand the agents that effect DNA movement: plasmids, bacteriophages and transposons. Although these agents occur in all prokaryotes, comprehensive genomics of the prokaryotic mobile gene pool or 'mobilome' lags behind other genomics initiatives owing to challenges that are distinct from cellular chromosomal analysis. Recent work shows promise of improved mobile genetic element (MGE) genomics and consequent opportunities to take advantage - and avoid the dangers - of these 'natural genetic engineers'. This review describes MGEs, their properties that are important in horizontal gene transfer, and current opportunities to advance MGE genomics.