9,666 research outputs found
Groundbased near-IR observations of the surface of Venus
We present images of the nightside of Venus taken in the near-infrared windows at 1.0, 1.1, 1.18, 1.28, 1.31, and 2.3 microns with the new infrared camera/spectrometer IRIS on the Anglo-Australian Telescope. These data were taken in spectral-mapping mode. This technique involves scanning the telescope perpendicular to the slit, while collecting spectra at successive slit positions across the planet. We produce data cubes with one spectral and two spatial dimensions. Images can be extracted over any wavelength regions. Each image has square pixels of 0.8 inch resolution. We reduced the scattered light from the sunlit crescent in images extracted from each window by subtracting images taken on either side of the window, where the Venus atmosphere is opaque. Unlike the short wavelength windows, which reveal thermal contrasts that originate primarily from the surface and deep atmosphere, the emission in the 2.3 microns window is produced at much higher altitudes (30-40 km). Emission contrasts seen near 2.3 microns are associated with horizontal variations in the cloud optical depths, and have rotation periods of about six days. We detect large contrasts in infrared emission (20-40 percent) across the disc of Venus in the 1.0-, 1.1-, 1.18-, 1.28-, and 1.31-micron images. Contrasts at these wavelengths may be due to a combination of variations in the optical depths of the overlying sulfuric acid clouds and differences in surface emission. Comparison with the 2.3-micron images show that the patterns seen in the 1.28- and 1.31-micron windows are consistent with cloud optical depth variations alone and require no contribution from the surface. However, images at 1.0, 1.1, and 1.8 microns from July 1991 show a dark feature having a contrast that increases with decreasing wavelength. This behavior is contrary to that expected of cloud absorption. Images taken on three successive days in October show another dark feature that is stationary with respect to the surface. These regions of lower emission correspond closely to the high-altitude surface regions of Beta Regio and Aphrodite Terra. The images can potentially reveal the near-infrared emissiveity of the surface of Venus, thereby complementing Magellan radar reflectivity and ground based radio emissivity measurements. The contrast ratio between highlands and plains is much smaller than would be expected for blackbody radiation from the surface along. Unlike at radio wavelengths, where the atmosphere is essentially transparent, at near-infrared wavelengths the atmosphere emits, absorbs, and scatters radiation, and can modify the observed topographically induced contrasts. The additional radiation from the atmosphere reduces the contrast, and further modification would be expected if terrain at different altitudes has different emissivities. A fit to our data therefore requires, and may constrain, a model of the lowest scale height of the atmosphere
The Wakefield District prolific and priority offender needs analysis and business case: final report
The multifaceted nature of weight-related self-stigma: Validation of the two-factor weight bias internalization scale (WBIS-2F)
This is the final version. Available from Frontiers Media via the DOI in this record.Internalized weight stigma (IWS) is generally operationalized as self-devaluation due to weight in higher-weight individuals. The most commonly used measure of IWS, the Weight Bias Internalization Scale (WBIS), was developed from an original pool of 19 items. Item selection was guided by statistical techniques based upon an a priori hypothesized unidimensional factor structure. The resulting 11-item scale mostly assesses appearance-related attitudes, fear of stigma, affect, and desire for change, all of which may be a natural response to societal weight stigma, even in the absence of self-devaluation. Items pertaining to self-blame, stigma awareness, perceived legitimacy of weight stigma, and most items pertaining to self-worth, were excluded from the final scale. It is unclear whether an a priori assumption of multi-dimensionality would have produced different results. Methods: Exploratory and confirmatory factor analysis of the original 19-item questionnaire was conducted in 931 higher-weight individuals. Results: A 13-item two-factor structure was identified. Factor 1 comprised seven items that could be loosely conceived as weight-related distress. Factor 2 comprised six items, all of which pertained to weight-related self-worth. Tested individually, the six items making up the self-devaluation factor were an excellent fit for the data on all fit indices. Conclusion: IWS is a multi-dimensional construct. The two-factor WBIS (WBIS-2F) provides options to explore the relationships between different aspects of IWS and upstream and downstream variables. The Self-Devaluation subscale is suitable for standalone use when weight-related self-devaluation per se is the construct of interest.Economic and Social Research Council (ESRC
Singing and COPD: a pilot randomized controlled trial of wellbeing and respiratory outcomes
Aims/objectives
To test whether a ten-week regular weekly group singing programme, with guided home practice, leads to improvement in COPD-specific health status, as assessed by the COPD Assessment Test (CAT, primary outcome).
To test whether the programme results in changes to health-related quality of life, mental health, breathlessness, lung function, functional exercise performance and breathing patterns (secondary outcomes).
Rationale
A number of randomized controlled trials (RCTs) exist which suggest that there are potential benefits to health and wellbeing of regular singing for people with COPD (Chronic Obstructive Pulmonary Disease). However, most rely on small samples, and findings across the different outcome measures are inconsistent, while interview studies tend to report consistent positive physical and psychological outcomes. Further research is therefore needed.
Approach
A single-blind, randomized controlled trial compared a structured, weekly group singing programme plus home practice between sessions over ten weeks, with a usual COPD treatment control. The sample was drawn from a local NHS population of people with COPD. Following baseline assessments, participants were allocated to a 10 week singing programme or a control.
Findings
Twenty-four individuals completed to follow-up. Measures at 12 weeks showed no significant differences between singing and control groups except for one item on the health status questionnaire (SF-36) which suggested the singers were less limited in their activities of daily living post-singing. Final follow-up, planned for 6 months post intervention, was aborted due to the COVID-19 pandemic.
Discussion and conclusion
The study failed to recruit to target. There remains a recruitment problem in RCTs of singing for COPD, resulting in inconclusive findings, which conflict with the positive qualitative evidence. A wide variety of reseach methods, as well as RCTs, are suggested to enable a better understanding of the impact of singing on COPD.
Trial registration number: ISRCTN42943709
Further SEASAT SAR coastal ocean wave analysis
Analysis techniques used to exploit SEASAT synthetic aperture radar (SAR) data of gravity waves are discussed and the SEASAT SAR's ability to monitor large scale variations in gravity wave fields in both deep and shallow water is evaluated. The SAR analysis techniques investigated included motion compensation adjustments and the semicausal model for spectral analysis of SAR wave data. It was determined that spectra generated from fast Fourier transform analysis (FFT) of SAR wave data were not significantly altered when either range telerotation adjustments or azimuth focus shifts were used during processing of the SAR signal histories, indicating that SEASAT imagery of gravity waves is not significantly improved or degraded by motion compensation adjustments. Evaluation of the semicausal (SC) model using SEASAT SAR data from Rev. 974 indicates that the SC spectral estimates were not significantly better than the FFT results
Near-infrared oxygen airglow from the Venus nightside
Groundbased imaging and spectroscopic observations of Venus reveal intense near-infrared oxygen airglow emission from the upper atmosphere and provide new constraints on the oxygen photochemistry and dynamics near the mesopause (approximately 100 km). Atomic oxygen is produced by the Photolysis of CO2 on the dayside of Venus. These atoms are transported by the general circulation, and eventually recombine to form molecular oxygen. Because this recombination reaction is exothermic, many of these molecules are created in an excited state known as O2(delta-1). The airglow is produced as these molecules emit a photon and return to their ground state. New imaging and spectroscopic observations acquired during the summer and fall of 1991 show unexpected spatial and temporal variations in the O2(delta-1) airglow. The implications of these observations for the composition and general circulation of the upper venusian atmosphere are not yet understood but they provide important new constraints on comprehensive dynamical and chemical models of the upper mesosphere and lower thermosphere of Venus
Lessons Learned from Radiative Transfer Simulations of the Venus Atmosphere
The Venus atmosphere is extremely complex, and because of this the spectrum of Earths sister planet is likewise intricate and a challenge to model accurately. However, accurate modeling of Venus spectrum opens up multiple opportunities to better understand the planet next door, and even for understanding Venus-like planets beyond our solar system. Near-infrared (1-2.5 um, NIR) spectral windows observable on the Venus nigthside present the opportunity to probe beneath the Venusian cloud deck and measure thermal emission from the surface and lower atmosphere remotely from Earth or from orbit. These nigthside spectral windows were discovered by Allen and Crawford (1984) and have since been used measure trace gas abundances in the Venus lower atmosphere (less than 45 km), map surface emissivity varisions, and measure properties of the lower cloud deck. These windows sample radiation from below the cloud base at roughly 45 km, and pressures in this region range from roughly Earthlike (approx. 1 bar) up to 90 bars at the surface. Temperatures in this region are high: they range from about 400 K at the base of the cloud deck up to about 740 K at the surface. This high temperature and pressure presents several challenges to modelers attempting radiative transfer simulations of this region of the atmosphere, which we will review. Venus is also important to spectrally model to predict the remote observables of Venus-like exoplanets in anticipation of data from future observatories. Venus-like planets are likely one of the most common types of terrestrial planets and so simulations of them are valuable for planning observatory and detector properties of future telescopes being designed, as well as predicting the types of observations required to characterize them
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