962 research outputs found
Optical properties of low background PEN structural components for the LEGEND-200 experiment
Polyethylene Naphthalate (PEN) plastic scintillator has been identified as
potential self-vetoing structural material in low-background physics
experiments. Scintillating components have been produced radio-pure from PEN
using injection compression molding technology. These low-background PEN
components will be used as active holders to mount the Germanium detectors in
the \legend- neutrinoless double beta decay experiment. In this paper we
present the measurement of the optical properties of these PEN components.
Thus, the emission spectrum, time constant, attenuation and bulk absorption
length as well as light output and light yield are reported. In addition, the
surface of these PEN components has been characterized and an estimation of the
surface roughness is presented. Moreover, the light output of the final
\legend- detector holders has been measured and is reported. These
measurements were used to estimate the self-vetoing efficiency of these
holders
Yoga for stroke rehabilitation
Background:
Stroke is a major health issue and cause of long-term disability and has a major emotional and socioeconomic impact. There is a need to explore options for long-term sustainable interventions that support stroke survivors to engage in meaningful activities to address life challenges after stroke. Rehabilitation focuses on recovery of function and cognition to the maximum level achievable, and may include a wide range of complementary strategies including yoga.
Yoga is a mind-body practice that originated in India, and which has become increasingly widespread in the Western world. Recent evidence highlights the positive effects of yoga for people with a range of physical and psychological health conditions. A recent non-Cochrane systematic review concluded that yoga can be used as self-administered practice in stroke rehabilitation.
Objectives:
To assess the effectiveness of yoga, as a stroke rehabilitation intervention, on recovery of function and quality of life (QoL).
Search methods:
We searched the Cochrane Stroke Group Trials Register (last searched July 2017), Cochrane Central Register of Controlled Trials (CENTRAL) (last searched July 2017), MEDLINE (to July 2017), Embase (to July 2017), CINAHL (to July 2017), AMED (to July 2017), PsycINFO (to July 2017), LILACS (to July 2017), SciELO (to July 2017), IndMED (to July 2017), OTseeker (to July 2017) and PEDro (to July 2017). We also searched four trials registers, and one conference abstracts database. We screened reference lists of relevant publications and contacted authors for additional information.
Selection criteria:
We included randomised controlled trials (RCTs) that compared yoga with a waiting-list control or no intervention control in stroke survivors.
Data collection and analysis:
Two review authors independently extracted data from the included studies. We performed all analyses using Review Manager (RevMan). One review author entered the data into RevMan; another checked the entries. We discussed disagreements with a third review author until consensus was reached. We used the Cochrane 'Risk of bias' tool. Where we considered studies to be sufficiently similar, we conducted a meta-analysis by pooling the appropriate data. For outcomes for which it was inappropriate or impossible to pool quantitatively, we conducted a descriptive analysis and provided a narrative summary.
Main results:
We included two RCTs involving 72 participants. Sixty-nine participants were included in one meta-analysis (balance). Both trials assessed QoL, along with secondary outcomes measures relating to movement and psychological outcomes; one also measured disability.
In one study the Stroke Impact Scale was used to measure QoL across six domains, at baseline and post-intervention. The effect of yoga on five domains (physical, emotion, communication, social participation, stroke recovery) was not significant; however, the effect of yoga on the memory domain was significant (mean difference (MD) 15.30, 95% confidence interval (CI) 1.29 to 29.31, P = 0.03), the evidence for this finding was very low grade. In the second study, QoL was assessed using the Stroke-Specifc QoL Scale; no significant effect was found.
Secondary outcomes included movement, strength and endurance, and psychological variables, pain, and disability.
Balance was measured in both studies using the Berg Balance Scale; the effect of intervention was not significant (MD 2.38, 95% CI -1.41 to 6.17, P = 0.22). Sensititivy analysis did not alter the direction of effect. One study measured balance self-efficacy, using the Activities-specific Balance Confidence Scale (MD 10.60, 95% CI -7.08,= to 28.28, P = 0.24); the effect of intervention was not significant; the evidence for this finding was very low grade.
One study measured gait using the Comfortable Speed Gait Test (MD 1.32, 95% CI -1.35 to 3.99, P = 0.33), and motor function using the Motor Assessment Scale (MD -4.00, 95% CI -12.42 to 4.42, P = 0.35); no significant effect was found based on very low-grade evidence.
One study measured disability using the modified Rankin Scale (mRS) but reported only whether participants were independent or dependent. No significant effect was found: (odds ratio (OR) 2.08, 95% CI 0.50 to 8.60, P = 0.31); the evidence for this finding was very low grade.
Anxiety and depression were measured in one study. Three measures were used: the Geriatric Depression Scale-Short Form (GCDS15), and two forms of State Trait Anxiety Inventory (STAI, Form Y) to measure state anxiety (i.e. anxiety experienced in response to stressful situations) and trait anxiety (i.e. anxiety associated with chronic psychological disorders). No significant effect was found for depression (GDS15, MD -2.10, 95% CI -4.70 to 0.50, P = 0.11) or for trait anxiety (STAI-Y2, MD -6.70, 95% CI -15.35 to 1.95, P = 0.13), based on very low-grade evidence. However, a significant effect was found for state anxiety: STAI-Y1 (MD -8.40, 95% CI -16.74 to -0.06, P = 0.05); the evidence for this finding was very low grade.
No adverse events were reported.
Quality of the evidence:
We assessed the quality of the evidence using GRADE. Overall, the quality of the evidence was very low, due to the small number of trials included in the review both of which were judged to be at high risk of bias, particularly in relation to incompleteness of data and selective reporting, and especially regarding the representative nature of the sample in one study.
Authors' conclusions:
Yoga has the potential for being included as part of patient-centred stroke rehabilitation. However, this review has identified insufficient information to confirm or refute the effectiveness or safety of yoga as a stroke rehabilitation treatment. Further large-scale methodologically robust trials are required to establish the effectiveness of yoga as a stroke rehabilitation treatment
A systematic review investigating fatigue, psychological and cognitive impairment following TIA and minor stroke:protocol paper
Approximately 20,000 people have a transient ischemic attack (TIA) and 23,375 have a minor stroke in England each year. Fatigue, psychological and cognitive impairments are well documented post-stroke. Evidence suggests that TIA and minor stroke patients also experience these impairments; however, they are not routinely offered relevant treatment. This systematic review aims to: (1) establish the prevalence of fatigue, anxiety, depression, post-traumatic stress disorder (PTSD) and cognitive impairment following TIA and minor stroke and to investigate the temporal course of these impairments; (2) explore impact on quality of life (QoL), change in emotions and return to work; (3) identify where further research is required and to potentially inform an intervention study
Quantification of Optic Disc Edema during Exposure to High Altitude Shows No Correlation to Acute Mountain Sickness
BACKGROUND: The study aimed to quantify changes of the optic nerve head (ONH) during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS). This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. METHODOLOGY/PRINCIPAL FINDINGS: A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3®) was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 m). Slitlamp biomicroscopy was used for clinical optic disc evaluation; AMS was assessed with Lake Louise (LL) and AMS-cerebral (AMS-c) scores; oxygen saturation (SpO₂) and heart rate (HR) were monitored. These parameters were used to correlate with changes at the ONH. After the first night spent at high altitude, incidence of AMS was 55% and presence of clinical optic disc edema (ODE) 79%. Key stereometric parameters of the HRT3® used to describe ODE (mean retinal nerve fiber layer [RNFL] thickness, RNFL cross sectional area, optic disc rim volume and maximum contour elevation) changed significantly at high altitude compared to baseline (p<0.05) and were consistent with clinically described ODE. All changes were reversible in all participants after descent. There was no significant correlation between parameters of ODE and AMS, SpO₂ or HR. CONCLUSIONS/SIGNIFICANCE: Exposure to high altitude leads to reversible ODE in the majority of healthy subjects. However, these changes did not correlate with AMS or basic physiologic parameters such as SpO₂ and HR. For the first time, a quantitative approach has been used to assess these changes during acute, non-acclimatized high altitude exposure. In conclusion, ODE presents a reaction of the body to high altitude exposure unrelated to AMS
Hypoxia perturbs endothelium by re-organizing cellular actin architecture: Nitric oxide offers limited protection
Exposure to hypoxia causes structural changes in the endothelial cell (EC) monolayer that alter its permeability. There was a report earlier of impairment of nitric oxide (NO) production in endothelium. Intervention of NO in the altered cellular arrangements of actin cytoskeleton in endothelium for rectification of paracellular gaps in endothelium under hypoxia was observed. The present study demonstrates hypoxia inducing paracellular gaps in hypoxia exposed blood capillaries in chick embryo extra vascular model. Phalloidin staining confirmed significant polymerization of actin and unique cellular localization of the F-actin bands under hypoxia treatments. Addition of spermine NONOate (SPNO), a NO donor, or reoxygenation to endothelial monolayer attenuated hypoxia-mediated effects on endothelial permeability with partial recovery of endothelial integrity through actin remodeling. The present study indicates link of hypoxia-induced actin-associated cytoskeletal rearrangements and paracellular gaps in the endothelium with a low NO availability in the hypoxia milieu. The author concludes that NO confers protection against hypoxia-mediated cytoskeletal remodeling and endothelial leakiness
Affordances, constraints and information flows as ‘leverage points’ in design for sustainable behaviour
Copyright @ 2012 Social Science Electronic PublishingTwo of Donella Meadows' 'leverage points' for intervening in systems (1999) seem particularly pertinent to design for sustainable behaviour, in the sense that designers may have the scope to implement them in (re-)designing everyday products and services. The 'rules of the system' -- interpreted here to refer to affordances and constraints -- and the structure of information flows both offer a range of opportunities for design interventions to in fluence behaviour change, and in this paper, some of the implications and possibilities are discussed with reference to parallel concepts from within design, HCI and relevant areas of psychology
A longitudinal study of the faecal microbiome and metabolome of periparturient mares
Periparturient mares are at increased risk of colic including large colon volvulus, which has a high mortality rate. Alterations in colonic microbiota related to either physiological or management changes, or both, that occur at this time have been suggested as potential causes for increased colic risk in this population of horses. Although the effect of management changes on the horse faecal microbiota has been investigated, limited work has been conducted to investigate changes in faecal microbiota structure and function in the periparturient period. The objectives of the current study were to investigate temporal stability of the faecal microbiota and volatile organic compounds (VOCs) of the faecal metabolome in periparturient mares
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Erratum: Production and validation of scintillating structural components from low-background Poly(ethylene naphthalate)
[no abstract available
Harnessing a High Cargo-Capacity Transposon for Genetic Applications in Vertebrates
Viruses and transposons are efficient tools for permanently delivering foreign DNA into vertebrate genomes but exhibit diminished activity when cargo exceeds 8 kilobases (kb). This size restriction limits their molecular genetic and biotechnological utility, such as numerous therapeutically relevant genes that exceed 8 kb in size. Furthermore, a greater payload capacity vector would accommodate more sophisticated cis cargo designs to modulate the expression and mutagenic risk of these molecular therapeutics. We show that the Tol2 transposon can efficiently integrate DNA sequences larger than 10 kb into human cells. We characterize minimal sequences necessary for transposition (miniTol2) in vivo in zebrafish and in vitro in human cells. Both the 8.5-kb Tol2 transposon and 5.8-kb miniTol2 engineered elements readily function to revert the deficiency of fumarylacetoacetate hydrolase in an animal model of hereditary tyrosinemia type 1. Together, Tol2 provides a novel nonviral vector for the delivery of large genetic payloads for gene therapy and other transgenic applications
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