The preparation and physical properties of certain chalcogenide semi-conductors

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Cost effectiveness of a community based exercise programme in over 65 year olds: cluster randomised trial

OBJECTIVE: To assess the cost effectiveness of a community based exercise programme as a population wide public health intervention for older adults. DESIGN: Pragmatic, cluster randomised community intervention trial. Setting: 12 general practices in Sheffield; four randomly selected as intervention populations, and eight as control populations. PARTICIPANTS: All those aged 65 and over in the least active four fifths of the population responding to a baseline survey. There were 2283 eligible participants from intervention practices and 4137 from control practices. INTERVENTION: Eligible subjects were invited to free locally held exercise classes, made available for two years. MAIN OUTCOME MEASURES: All cause and exercise related cause specific mortality and hospital service use at two years, and health status assessed at baseline, one, and two years using the SF-36. A cost utility analysis was also undertaken. RESULTS: Twenty six per cent of the eligible intervention practice population attended one or more exercise sessions. There were no significant differences in mortality rates, survival times, or admissions. After adjusting for baseline characteristics, patients in intervention practices had a lower decline in health status, although this reached significance only for the energy dimension and two composite scores (p,0.05). The incremental average QALY gain of 0.011 per person in the intervention population resulted in an incremental cost per QALY ratio of J17 174 (95% CI =J8300 to J87 120). CONCLUSIONS: Despite a low level of adherence to the exercise programme, there were significant gains in health related quality of life. The programme was more cost effective than many existing medical interventions, and would be practical for primary care commissioning agencies to implement

Optimal management of urinary tract infections in older people

Urinary tract infections (UTI) occur frequently in older people. Unfortunately, UTI is commonly overdiagnosed and overtreated on the basis of nonspecific clinical signs and symptoms. The diagnosis of a UTI in the older patient requires the presence of new urinary symptoms, with or without systemic symptoms. Urinalysis is commonly used to diagnose infection in this population, however, the evidence for its use is limited. There is overwhelming evidence that asymptomatic bacteriuria should not be treated. Catheter associated urinary tract infection accounts for a significant amount of hospital-associated infection. Indwelling urinary catheters should be avoided where possible and alternatives sought. The use of narrow spectrum antimicrobial agents for urinary tract infection is advocated. Local guidelines are now widely used to reflect local resistance patterns and available agents. Guidelines need to be updated to reflect changes in antimicrobial prescribing and a move from broad to narrow spectrum antimicrobials

Effectiveness of a simple lymphoedema treatment regimen in podoconiosis management in southern Ethiopia: one year follow-up

Background: Podoconiosis is a non-filarial elephantiasis caused by long-term barefoot exposure to volcanic soils in endemic areas. Irritant silicate particles penetrate the skin, causing a progressive, debilitating lymphoedema of the lower leg, often starting in the second decade of life. A simple patient-led treatment approach appropriate for resource poor settings has been developed, comprising (1) education on aetiology and prevention of podoconiosis, (2) foot hygiene (daily washing with soap, water and an antiseptic), (3) the regular use of emollient, (4) elevation of the limb at night, and (5) emphasis on the consistent use of shoes and socks. Methodology/Principal Findings: We did a 12-month, non-comparative, longitudinal evaluation of 33 patients newly presenting to one clinic site of a non-government organization (the Mossy Foot Treatment & Prevention Association, MFTPA) in southern Ethiopia. Outcome measures used for the monitoring of disease progress were (1) the clinical staging system for podoconiosis, and (2) the Amharic Dermatology Life Quality Index (DLQI), both of which have been recently validated for use in this setting. Digital photographs were also taken at each visit. Twenty-seven patients completed follow up. Characteristics of patients completing follow-up were not significantly different to those not. Mean clinical stage and lower leg circumference decreased significantly (mean difference -0.67 (95% CI -0.38 to -0.96) and -2.00 (95% CI -1.26 to -2.74), respectively, p<0.001 for both changes). Mean DLQI diminished from 21 (out of a maximum of 30) to 6 (p<0.001). There was a non-significant change in proportion of patients with mossy lesions (p = 0.375). Conclusions/Significance: This simple, resource-appropriate regimen has a considerable impact both on clinical progression and self-reported quality of life of affected individuals. The regimen appears ideal for scaling up to other endemic regions in Ethiopia and internationally. We recommend that further research in the area include analysis of cost-effectiveness of the regimen

Deceleration and Dispersion of Large-scale Coronal Bright Fronts

One of the most dramatic manifestations of solar activity are large-scale coronal bright fronts (CBFs) observed in extreme ultraviolet (EUV) images of the solar atmosphere. To date, the energetics and kinematics of CBFs remain poorly understood, due to the low image cadence and sensitivity of previous EUV imagers and the limited methods used to extract the features. In this paper, the trajectory and morphology of CBFs was determined in order to investigate the varying properties of a sample of CBFs, including their kinematics and pulse shape, dispersion, and dissipation. We have developed a semi-automatic intensity profiling technique to extract the morphology and accurate positions of CBFs in 2.5-10 min cadence images from STEREO/EUVI. The technique was applied to sequences of 171A and 195A images from STEREO/EUVI in order to measure the wave properties of four separate CBF events. Following launch at velocities of ~240-450kms^{-1} each of the four events studied showed significant negative acceleration ranging from ~ -290 to -60ms^{-2}. The CBF spatial and temporal widths were found to increase from ~50 Mm to ~200 Mm and ~100 s to ~1500 s respectively, suggesting that they are dispersive in nature. The variation in position-angle averaged pulse-integrated intensity with propagation shows no clear trend across the four events studied. These results are most consistent with CBFs being dispersive magnetoacoustic waves.Comment: 15 pages, 18 figure

Weathering of the Ethiopian volcanic province: a new weathering index to characterize and compare soils

© Walter de Gruyter Berlin/Boston 2015.Soil formation occurs through numerous physical and chemical weathering processes acting to alter the parent rock on the Earths surface. Samples of surface soils were collected over a range of elevations (2000-3600 m) from profiles directly overlying basaltic to more felsic parent rocks, over a region in NW Ethiopia. The soils were investigated to determine their chemical composition and X-ray diffraction was used to identify and quantify individual mineral phases. The data set was analyzed using non-parametric statistics (Spearmans Rank and Mann-Whitney U tests) to compare the soils forming over the two parent rocks. Principal component analysis (PCA) was used to identify the mineral alteration assemblage and formation during pedogenesis. The extent of alteration was quantified using several chemical weathering indices (Chemical Index of Alteration = CIA; Chemical Index of Weathering = CIW), including an index calculated by multivariate analyses of the soil chemical composition data (weathering W index). Further to this we devised and tested a new weathering index (Wmin) using multivariate analysis of the soil mineralogy, to estimate the extent of weathering and physico-chemical proprieties of the parent rock from which the soil formed. The soils present a fair to advanced stage of alteration, with abundant iron (Fe) oxides (up to 40 wt%) and phyllosilicates (up to 57 wt%), including kaolinite-smectite (K-S) mixed-layer phases. The K-S was composed of either 30-50% kaolinite or 94-98% kaolinite layers. Discrete kaolinite was also present. The bimodal K-S mineralogical composition is likely due to two precursor phases: feldspar for the kaolinite-rich K-S and volcanic glass for the smectite-rich K-S. K-S with intermediate composition (50-94% kaolinite) was rare, due to its instability. Statistical analysis showed significant differences between the chemical compositions of the soils developed on the two different parent volcanic compositions. The soils overlying the more felsic parent rocks were less altered than those overlying the flood basalt. When comparing the weathering indices calculated in this study, we conclude that while the CIA and CIW may be more readily determined, the W and Wmin indices can elucidate information on the composition of the original rock from which they formed. The W index is more sensitive to certain variables when compared with the newly derived mineralogical Wmin index; however the Wmin index takes into account mineral phases within the sample, which provides a more detailed interpretation of weathering rates than chemistry alone. In addition the Wmin index correlated with meteorological variables, such as elevation (and consequently temperature and precipitation), known to influence the degree of pedogenesis. The Wmin index can be used to enhance our understanding of the processes that occur during weathering processes to supplement information gained from traditional chemical weathering indices

Structural plasticity and associative memory in balanced neural networks with spike-time dependent inhibitory plasticity

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