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.

Organizational Design Types, Tracks and the Dynamics of Strategic Change

Abstract: Change and stability in organizations is to be understood through the twin concepts of design archetypes and tracks. Organizations operate with structural designs which are given meaning and coherence by underlying interpretive schemes. Particular interpre tive schemes coupled with associated structural arrangements constitute a design archetype. The temporal relationship between an organization and one or more archetypes defines an organization's track. Prototypical tracks include inertia, aborted excursions, re-orientations and unresolved excursions. The particular track followed by an organization will be a function of the degree of alignment or compatibility between structures and contingency constraints, the pattern of commitment to prevailing and alternative interpretive schemes and the incidence of interest dissatisfaction of powerful groups.

Net effects of multiple stressors in freshwater ecosystems: a meta-analysis

Abstract: The accelerating rate of global change has focused attention on the cumulative impacts of novel and extreme environmental changes (i.e. stressors), especially in marine ecosystems. As integrators of local catchment and regional processes, freshwater ecosystems are also ranked highly sensitive to the net effects of multiple stressors, yet there has not been a large-scale quantitative synthesis. We analysed data from 88 papers including 286 responses of freshwater ecosystems to paired stressors and discovered that overall, their cumulative mean effect size was less than the sum of their single effects (i.e. an antagonistic interaction). Net effects of dual stressors on diversity and functional performance response metrics were additive and antagonistic, respectively. Across individual studies, a simple vote-counting method revealed that the net effects of stressor pairs were frequently more antagonistic (41%) than synergistic (28%), additive (16%) or reversed (15%). Here, we define a reversal as occurring when the net impact of two stressors is in the opposite direction (negative or positive) from that of the sum of their single effects. While warming paired with nutrification resulted in additive net effects, the overall mean net effect of warming combined with a second stressor was antagonistic. Most importantly, the mean net effects across all stressor pairs and response metrics were consistently antagonistic or additive, contrasting the greater prevalence of reported synergies in marine systems. Here, a possible explanation for more antagonistic responses by freshwater biota to stressors is that the inherent greater environmental variability of smaller aquatic ecosystems fosters greater potential for acclimation and co-adaptation to multiple stressors.

Radiative Absorption Enhancements Due to the Mixing State of Atmospheric Black Carbon

Abstract: Atmospheric black carbon (BC) warms Earth’s climate, and its reduction has been targeted for near-term climate change mitigation. Models that include forcing by BC assume internal mixing with non-BC aerosol components that enhance BC absorption, often by a factor of ~2; such model estimates have yet to be clearly validated through atmospheric observations. Here, direct in situ measurements of BC absorption enhancements ( E abs ) and mixing state are reported for two California regions. The observed E abs is small—6% on average at 532 nm—and increases weakly with photochemical aging. The E abs is less than predicted from observationally constrained theoretical calculations, suggesting that many climate models may overestimate warming by BC. These ambient observations stand in contrast to laboratory measurements that show substantial E abs for BC are possible.

Baloxavir Marboxil for Uncomplicated Influenza in Adults and Adolescents

Abstract: Background Baloxavir marboxil is a selective inhibitor of influenza cap-dependent endonuclease. It has shown therapeutic activity in preclinical models of influenza A and B virus infection...

Pregabalin for acute and chronic pain in adults

Abstract: Background Antiepileptic drugs have been used in pain management since the 1960s. Pregabalin is a recently developed antiepileptic drug also used in management of chronic neuropathic pain conditions. Objectives To assess analgesic efficacy and associated adverse events of pregabalin in acute and chronic pain. Search methods We searched MEDLINE, EMBASE, and CENTRAL to May 2009 for randomised controlled trials (RCTs). Additional studies were identified from the reference lists of retrieved papers and on-line clinical trial databases. Selection criteria Randomised, double blind trials reporting on the analgesic effect of pregabalin, with subjective pain assessment by the patient as either the primary or a secondary outcome. Data collection and analysis Two independent review authors extracted data and assessed trial quality. Numbers-needed-to-treat-to-benefit (NNTs) were calculated, where possible, from dichotomous data for effectiveness, adverse events and study withdrawals. Main results There was no clear evidence of beneficial effects of pregabalin in established acute postoperative pain. No studies evaluated pregabalin in chronic nociceptive pain, like arthritis. Pregabalin at doses of 300 mg, 450 mg, and 600 mg daily was effective in patients with postherpetic neuralgia, painful diabetic neuropathy, central neuropathic pain, and fibromyalgia (19 studies, 7003 participants). Pregabalin at 150 mg daily was generally ineffective. Efficacy was demonstrated for dichotomous outcomes equating to moderate or substantial pain relief, alongside lower rates for lack of efficacy discontinuations with increasing dose. The best (lowest) NNT for each condition for at least 50% pain relief over baseline (substantial benefit) for 600 mg pregabalin daily compared with placebo were 3.9 (95% confidence interval 3.1 to 5.1) for postherpetic neuralgia, 5.0 (4.0 to 6.6) for painful diabetic neuropathy, 5.6 (3.5 to 14) for central neuropathic pain, and 11 (7.1 to 21) for fibromyalgia. With 600 mg pregabalin daily somnolence typically occurred in 15% to 25% and dizziness occurred in 27% to 46%. Treatment was discontinued due to adverse events in 18 to 28%. The proportion of participants reporting at least one adverse event was not affected by dose, nor was the number with a serious adverse event, which was not more than with placebo. Higher rates of substantial benefit were found in postherpetic neuralgia and painful diabetic neuropathy than in central neuropathic pain and fibromyalgia. For moderate and substantial benefit on any outcome NNTs for the former were generally six and below for 300 mg and 600 mg daily; for fibromyalgia NNTs were much higher, and generally seven and above. Authors' conclusions Pregabalin has proven efficacy in neuropathic pain conditions and fibromyalgia. A minority of patients will have substantial benefit with pregabalin, and more will have moderate benefit. Many will have no or trivial benefit, or will discontinue because of adverse events. Individualisation of treatment is needed to maximise pain relief and minimise adverse events. There is no evidence to support the use of pregabalin in acute pain scenarios.