3,244 research outputs found
Simultaneous bilateral training for improving arm function after stroke
No full textBackground Simultaneous bilateral training, the completion of identical activities with both arms simultaneously, is one intervention to improve arm function and reduce impairment. Objectives To determine the effects of simultaneous bilateral training for improving arm function after stroke. Search strategy We searched the Cochrane Stroke Trials Register (last searched August 2009) and 10 electronic bibliographic databases including the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2009), MEDLINE, EMBASE, CINAHL and AMED (August 2009). We also searched reference lists and trials registers. Selection criteria Randomised trials in adults after stroke, where the intervention was simultaneous bilateral training compared to placebo or no intervention, usual care or other upper limb (arm) interventions. Primary outcomes were performance in activities of daily living (ADL) and functional movement of the upper limb. Secondary outcomes were performance in extended activities of daily living and motor impairment of the arm. Data collection and analysis Two authors independently screened abstracts, extracted data and appraised trials. Assessment of methodological quality was undertaken for allocation concealment, blinding of outcome assessor, intention-to-treat, baseline similarity and loss to follow up. Main results We included 18 studies involving 549 relevant participants, of which 14 (421 participants) were included in the analysis (one within both comparisons). Four of the 14 studies compared the effects of bilateral training with usual care. Primary outcomes: results were not statistically significant for performance in ADL (standardised mean difference (SMD) 0.25, 95% confidence interval (CI) -0.14 to 0.63); functional movement of the arm (SMD -0.07, 95% CI -0.42 to 0.28) or hand (SMD -0.04, 95% CI -0.50 to 0.42). Secondary outcomes: no statistically significant results. Eleven of the 14 studies compared the effects of bilateral training with other specific upper limb (arm) interventions. Primary outcomes: no statistically significant results for performance of ADL (SMD -0.25, 95% CI -0.57 to 0.08); functional movement of the arm (SMD -0.20, 95% CI -0.49 to 0.09) or hand (SMD -0.21, 95% CI -0.51 to 0.09). Secondary outcomes: one study reported a statistically significant result in favour of another upper limb intervention for performance in extended ADL. No statistically significant differences were found for motor impairment outcomes. Authors' conclusions There is insufficient good quality evidence to make recommendations about the relative effect of simultaneous bilateral training compared to placebo, no intervention or usual care. We identified evidence that suggests that bilateral training may be no more (or less) effective than usual care or other upper limb interventions for performance in ADL, functional movement of the upper limb or motor impairment outcome
Nadere verfijning DUROSTA-model: Toetsing H/Tw-parameter en aanpassing t.b.v. porositeitsverschillen en strandtransporten
No full textTeneinde het DUROSTA-model verder te verbeteren zijn de effecten modellering nader onderzocht en is de schaalgrootheid H/Tw nader bekeken.TAW/EN
Development of a rotor model for the numerical simulation of helicopter exterior flow-fields
No full textIncludes bibliographical references (leaves 84-85).A numerical methodology is developed to model the effect of a rotor on the surrounding flow-field. The model calculates the time-averaged aerodynamic forces exerted on the air by the fan blades within the blade-swept region, and permits the user to specify blade properties such as cross-sectional profile and orientation at a particular radial and azimuthal location. The calculated forces are included as source terms within the Reynolds-averaged Navier-Stokes equations for an incompressible fluid, which are solved by the commercial CFD solver, FLUENT. The effects of turbulence are incorporated through the use of Launder and Spalding's k-g turbulence model. This method is selected as being the most efficient use of the resources available, giving the economic advantages of a steady simulation, while allowing radial and azimuthal variations of rotor characteristics. In order to validate the accuracy of the numerical model for both aligned and non-aligned inflow conditions, results are compared with experimental data reported for an axial flow fan. Agreement between experimental and numerical results is excellent to good. Fan static pressure rise is closely predicted by the numerical solution, while fan power consumption and fan static efficiency are under and over-predicted respectively. This error may be attributed to frictional losses not accounted for in the numerical model. These include physical rotational instabilities, leading to increased mechanical losses, and tip effects due to the clearance between the fan blade tips and the fan casing. Trends are nevertheless consistently predicted by the numerical model for inflow angles up to 45°, and for the range of blade pitch settings used. The adverse effect of off-axis inflow on the fan static pressure rise is numerically predicted, while fan power consumption is found to remain independent of inflow angle, as had been experimentally observed. The rotor model is finally integrated with the fuselage of the CIRSTEL (Combined Infra-Red Suppression and Tail rotor Elimination) prototype in an analysis of the helicopter exterior flow-field. No experimental data for this configuration was available for validation purposes. However, the model is used in the simulation of several common helicopter flight conditions. Results are presented graphically, and generally indicate good agreement with physically observed phenomena
Third body effects in the period changes of two Algol binaries: V342 Aql and TW Lac
No full text32nd International Physics Congress of Turkish-Physical-Society (TPS) -- SEP 06-09, 2016 -- Bodrum, TURKEYThe O - C diagrams of two Algol-type eclipsing binaries V342 Aql and TW Lac have been analyzed with the least-squares method by using all available minima times. The period changes in their O - C diagrams have been discussed with respect to the Light-Time Effect (LITE) that originates from gravitational influence of a third body. New LITE elements, orbital periods and possible minimum masses of third bodies are given.Turkish Phys So
Increasing science, technology, engineering, and mathematics skills using Project Lead the Way
No full textIncludes bibliographical references
Cardiovascular disease--linking pathology and epidemiology.
No full textBACKGROUND: Coronary heart disease (CHD) in the form of myocardial infarction first came to attention early in the 20th century. Mortality from CHD increased dramatically after the First World War and had assumed epidemic proportions, particularly in the USA, by 1945. The ensuing research stemmed almost exclusively from the lipid infiltration hypothesis for atheroma. METHODS: Using epidemiological methods, pathological evidence for the thrombotic component of CHD was demonstrated by Morris as early as 1951. Morris's main work was based, first, on routine autopsy records at the London (now Royal London) Hospital and, second, on the National Necropsy Survey relating physical activity at work to pathological findings. RESULTS: The indications from Morris's work that thrombosis contributes as much to clinical CHD as atheroma were in due course strengthened by the findings of clinical trials of aspirin, prospective studies incorporating measures of haemostatic function and further studies of pathology. CONCLUSIONS: Recognition of the thrombotic contribution to CHD does not materially alter approaches to prevention through lifestyle modifications but does have major implications for pharmacological measures. Thus, aspirin and thrombolytic therapy are mandatory in the acute stage of suspected myocardial infarction while aspirin is also part of accepted practice in the longer term in secondary prevention. The value of warfarin is being rediscovered, often at a lower and therefore safer intensity of anticoagulation than previously considered necessary. The effect that warfarin may have on the vessel wall as well as on occlusion of the lumen is helping to reconcile the two major hypotheses for the pathology of CHD. Much of our current knowledge about the origins, management and prevention of CHD stems from Morris's early studies linking pathology and epidemiology
Psychological, social and welfare interventions for psychological health and well-being of torture survivors
No full textThis is the protocol for a review and there is no abstract. The objectives are as follows: Primary objective 1. To assess beneficial and adverse effects of psychological, social and welfare interventions versus no treatment for the reduction of psychological distress in torture survivors. Secondary objectives 2. To describe the quality and generalisability of the studies evaluating the effects of these treatment approaches on torture survivors, and specifically: • to provide an objective assessment of risk of bias in these studies; • to describe the specific populations evaluated in studies of torture survivors (including demographics, torture experiences and psychological status); • to describe the variety of interventions that have been evaluated in these populations; and • to describe the outcomes evaluated in these intervention studies
High-efficiency supercontinuum generation in solid thin plates at 0.1 TW level
No full text
Supercontinuum generation in a solid-state medium was investigated experimentally. A continuum covering 460 to 950 nm was obtained when 0.8 mJ/30 fs Ti: sapphire laser pulses were applied to seven thin fused silica plates at a 1 kHz repetition rate. The primary processes responsible for spectral broadening were self-phase modulation (SPM) and self-steepening, while SPM and self-focusing were balanced to optimize the spectral broadening and suppress the multi-photon process. The output was compressed to a 5.4 fs and a 0.68 mJ pulse, corresponding to two optical cycles and 0.13 TW of peak power. (C) 2017 Optical Society of America</p
Physiotherapy approaches for the recovery of postural control and lower limb function following stroke: a systematic review
No full text<b>Background</b><p></p>
Various approaches to physical rehabilitation may be used after stroke, and considerable controversy and debate surround the effectiveness of relative approaches. Some physiotherapists base their treatments on a single approach; others use a mixture of components from several different approaches.<p></p>
<b>Objectives</b><p></p>
To determine whether physical rehabilitation approaches are effective in recovery of function and mobility in people with stroke, and to assess if any one physical rehabilitation approach is more effective than any other approach.<p></p>
For the previous versions of this review, the objective was to explore the effect of 'physiotherapy treatment approaches' based on historical classifications of orthopaedic, neurophysiological or motor learning principles, or on a mixture of these treatment principles. For this update of the review, the objective was to explore the effects of approaches that incorporate individual treatment components, categorised as functional task training, musculoskeletal intervention (active), musculoskeletal intervention (passive), neurophysiological intervention, cardiopulmonary intervention, assistive device or modality.<p></p>
In addition, we sought to explore the impact of time after stroke, geographical location of the study, dose of the intervention, provider of the intervention and treatment components included within an intervention.<p></p>
<b>Search methods</b><p></p>
We searched the Cochrane Stroke Group Trials Register (last searched December 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 12, 2012), MEDLINE (1966 to December 2012), EMBASE (1980 to December 2012), AMED (1985 to December 2012) and CINAHL (1982 to December 2012). We searched reference lists and contacted experts and researchers who have an interest in stroke rehabilitation.<p></p>
<b>Selection criteria</b><p></p>
Randomised controlled trials (RCTs) of physical rehabilitation approaches aimed at promoting the recovery of function or mobility in adult participants with a clinical diagnosis of stroke. Outcomes included measures of independence in activities of daily living (ADL), motor function, balance, gait velocity and length of stay. We included trials comparing physical rehabilitation approaches versus no treatment, usual care or attention control and those comparing different physical rehabilitation approaches.<p></p>
<b>Data collection and analysis</b><p></p>
Two review authors independently categorised identified trials according to the selection criteria, documented their methodological quality and extracted the data.<p></p>
<b>Main results</b><p></p>
We included a total of 96 studies (10,401 participants) in this review. More than half of the studies (50/96) were carried out in China. Generally the studies were heterogeneous, and many were poorly reported.<p></p>
Physical rehabilitation was found to have a beneficial effect, as compared with no treatment, on functional recovery after stroke (27 studies, 3423 participants; standardised mean difference (SMD) 0.78, 95% confidence interval (CI) 0.58 to 0.97, for Independence in ADL scales), and this effect was noted to persist beyond the length of the intervention period (nine studies, 540 participants; SMD 0.58, 95% CI 0.11 to 1.04). Subgroup analysis revealed a significant difference based on dose of intervention (P value < 0.0001, for independence in ADL), indicating that a dose of 30 to 60 minutes per day delivered five to seven days per week is effective. This evidence principally arises from studies carried out in China. Subgroup analyses also suggest significant benefit associated with a shorter time since stroke (P value 0.003, for independence in ADL).<p></p>
We found physical rehabilitation to be more effective than usual care or attention control in improving motor function (12 studies, 887 participants; SMD 0.37, 95% CI 0.20 to 0.55), balance (five studies, 246 participants; SMD 0.31, 95% CI 0.05 to 0.56) and gait velocity (14 studies, 1126 participants; SMD 0.46, 95% CI 0.32 to 0.60). Subgroup analysis demonstrated a significant difference based on dose of intervention (P value 0.02 for motor function), indicating that a dose of 30 to 60 minutes delivered five to seven days a week provides significant benefit. Subgroup analyses also suggest significant benefit associated with a shorter time since stroke (P value 0.05, for independence in ADL).<p></p>
No one physical rehabilitation approach was more (or less) effective than any other approach in improving independence in ADL (eight studies, 491 participants; test for subgroup differences: P value 0.71) or motor function (nine studies, 546 participants; test for subgroup differences: P value 0.41). These findings are supported by subgroup analyses carried out for comparisons of intervention versus no treatment or usual care, which identified no significant effects of different treatment components or categories of interventions.<p></p>
<b>Authors' conclusions</b><p></p>
Physical rehabilitation, comprising a selection of components from different approaches, is effective for recovery of function and mobility after stroke. Evidence related to dose of physical therapy is limited by substantial heterogeneity and does not support robust conclusions. No one approach to physical rehabilitation is any more (or less) effective in promoting recovery of function and mobility after stroke. Therefore, evidence indicates that physical rehabilitation should not be limited to compartmentalised, named approaches, but rather should comprise clearly defined, well-described, evidenced-based physical treatments, regardless of historical or philosophical origin
Flow compensation in a MEMS dual-thermal conductivity detector for hydrogen sensing in natural gas
No full textConventional thermal conductivity detectors (TCDs) demonstrate a flow dependence. The approach presented here to reduce the flow dependence is based on the on-line flow compensation using two thin-film sensors on membranes in parallel on the same chip that are differentially operated. These are laterally identically, but with a different depth of the detection chamber, resulting in different quasi-static sensitivities to the thermal conductivity of the sample gas. The effects of conduction and convection in the structure have been studied using COMSOL Multiphysics. First prototypes have been fabricated and are presently tested.Accepted Author ManuscriptElectronic Instrumentatio
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