1,567 research outputs found
Recommended from our members
A Study of the Relationship Between Health and Subjective Well-being in Parkinson’s Disease Patients
Objectives: In light of the apparent disconnect between traditional measures of societal well-being such as GDP and reported levels of happiness, governments globally are turning their attention to alternative subjective measures of well-being (SWB) to aid policy decisions. In the context of health, there is therefore growing interest in understanding how measures of health-related quality of life (HRQoL), widely used in health technology appraisal, relates to SWB, and whether SWB could provide a sound basis for resource allocation decisions in health and other sectors in the future. This study investigates the relationship between HRQoL, as measured by EQ-5D, and SWB in Parkinson’s disease (PD) and the extent to which patients’ self-reported health can explain (part of) their SWB.
Methods: A paper questionnaire including EQ-5D, four key SWB questions taken from the Office for National Statistics Integrated Household Survey in England and other demographic details was distributed to people with PD in the UK. Responses were used to estimate multiple regression models explaining SWB using each of the EQ-5D Index (UK weights), EQ-5D dimensions and EQ-VAS and patient socio-demographic characteristics.
Results: 276 questionnaires were distributed and 183 responses received. The EQ-5D Index was a moderate predictor of SWB (adjusted R2 range 0.19-0.38 in OLS models), but EQ-VAS performed better (adjusted R2 range 0.32-0.49).
Combining EQ-VAS and EQ-5D dimensions, especially anxiety/depression and mobility, and household status in some cases, yielded the best-fitting models (adjusted R2 range 0.40-0.52).
Conclusions: The findings imply that EQ-VAS and some dimensions of the EQ-5D, together with key demographic data, could potentially be used to predict SWB, e.g. via mapping. However, further empirical research into the relationship between SWB and EQ-5D longitudinally, and in different disease areas, is required to corroborate these findings, and further standardisation of SWB measures is recommended
SPH simulations of the chemical evolution of bulges
We have implemented a chemical evolution model on the parallel AP3M+SPH DEVA
code which we use to perform high resolution simulations of spiral galaxy
formation. It includes feedback by SNII and SNIa using the Qij matrix
formalism. We also include a diffusion mechanism that spreads newly introduced
metals. The gas cooling rate depends on its specific composition. We study the
stellar populations of the resulting bulges finding a potential scenario where
they seem to be composed of two populations: an old, metal poor,
-enriched population, formed in a multiclump scenario at the beginning
of the simulation and a younger one, formed by slow accretion of satellites or
gas, possibly from the disk due to instabilities.Comment: 2 pages, 3 figures. Proceedings of IAUS 245 "Formation and Evolution
of Galaxy Bulges
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
Poly (N-isopropylacrylamide) Microgel-based Etalons and Etalon Arrays for Determining the Molecular Weight of Polymers in Solution
Positively and/or negatively charged poly (N-isopropylacrylamide)-based microgels were deposited on a single substrate and isolated regions of Au overlayers were deposited on top of the microgels. Each spatially isolated Au overlayer region had a different thickness to make an etalon array.We found that areas with a thin Au overlayer (5 nm) responded to a range of polymer molecular weights (MW), while areas with a thick overlayer (35 nm) can only respond to low molecular weight polyelectrolytes. By comparing the optical responses of the device’s individual array elements, a good approximation of the polyelectrolyteMWin solution can be made
Label-free Detection of Low Protein Concentration in Solution Using a Novel Colorimetric Assay
Dual pH and temperature sensitive microgel-based etalons were fabricated by sandwiching a “monolithic” microgel layer between two semitransparent, Au layers. The devices exhibit visual color and multipeak reflectance spectra, both of which primarily depend on the distance between the Au surfaces mediated by the microgel diameter. We found that a polycationic polyelectrolyte can penetrate through the Au overlayer to interact with negatively charged microgel confined between Au overlayers. In this submission we report that biotinylated polycationic polymer can penetrate through the Au overlayer of a poly (N-isopropylacrylamide)-co-acrylic acid (pNIPAm-co-AAc) microgel-based etalon and cause the microgel layer to collapse. The collapse results in a shift in the spectral peaks of the reflectance spectra. We found that the extent of peak shift depends on the amount of biotinylated polycation added to the etalon, which can subsequently be used to determine the concentration of streptavidin in solution at pM concentrations
A Novel Label-Free Colorimetric Assay for DNA Concentration in Solution
Optical devices were fabricated by sandwiching a “monolithic” poly(N-isopropylacrylamide-co-N-(3-aminopropyl) methacrylamide hydrochloride) (pNIPAm-co-APMAH) microgel layer between two semitransparent Au layers. These devices, referred to as etalons, exhibit characteristic multipeak reflectance spectra, and the position of the peaks in the spectra primarily depends on the distance between the Au surfaces mediated by the microgel layer thickness. Here, we show that the positively charged microgel layer can collapse in the presence of negatively charged single stranded DNA (ssDNA) due to ssDNA induced microgel crosslinking. The collapse results in a change in the etalon\u27s optical properties, which can be used to detect target DNA in a complex mixture
Poly (N-isopropylacrylamide) Microgel-Based Thin Film Actuators for Humidity Sensing
In this submission we fabricated a humidity-responsive polymer-based actuator by layering negatively charged poly(N-isopropylacrylamide)-co-acrylic acid microgels and positively charged poly(diallyldimethyl ammonium chloride) on top of a flexible plastic substrate. We show that the extent of the actuation (bending) was dependent on the atmospheric humidity. This property was used to detect atmospheric humidity by hanging weights from the actuator, which were rested on the pan of a top loading balance. This was done in such a way that the amount of the mass resting on the balance depended on the extent of actuator bending, which could then be related to humidity. We found the mass read by the balance to be linearly dependent on the atmospheric humidity in the range of 0–50% humidity, and the devices could be used to detect 0.02% humidity changes. These experiments show that the actuation of the devices can be used for sensing applications, in this case humidity, but will be used in the future to detect various atmospheric gases and other vapors
Utilización de fijadores externos circulares en el tratamiento de la pseudoartrosis infectada de tibia secuela de aplastamiento de miembros
Se revisan 7 casos de pseudoartrosis infectada de tibia, secuela de aplastamiento
de miembros, tratadas inicialmente en el momento de la fractura con desbridamiento y fijador externo
monolateral. Todos los casos eran iniciamente fracturas abiertas grado III de Gustilo. El tratamiento
de la pseudoartrosis se realizó mediante desbridamiento, estabilización con fijador externo
circular, cobertura de partes blandas e injerto óseo. La unión ósea se consiguió en todos los
casos con una buena recuperación funcional. Se discuten las ventajas del fijador externo circular
en estos casos.Seven patients with infected tibial pseuarthrosis due to crush injuries of the lower
extremity and treated by using circular cxternal fixators were reviewed. All cases had tibial
open fractures, Gustillo's type III. Treatment consisted of debridement, stabilization with a circular
device, bone graft and coverage of soft tissues. Bone union «as achieved in all cases with a satisfactory
functional recovery. The advantages of external fixators for this type of lesion are addressed
- …