1,185 research outputs found
Geography and art: encountering place across disciplines
This article summarises a project undertaken at the Newton Park campus of Bath Spa University over 1 week in October 2015. The project provided a space for interdisciplinary collaborations between geography and art students to explore the commonalities and differences in how they saw, interpreted and creatively re-presented the campus, using a variety of methods. This article outlines the project and reflects on the processes, outcomes, and challenges of collaboration. It highlights how this approach can enhance student learning experiences, by facilitating more interdisciplinary collaboration across the sciences, arts and humanities, and social sciences. In doing so, it explores the potential and pitfalls of collaborative cultural geography in practice across disciplines
Thomas-Fermi Calculations of Atoms and Matter in Magnetic Neutron Stars II: Finite Temperature Effects
We present numerical calculations of the equation of state for dense matter
in high magnetic fields, using a temperature dependent Thomas-Fermi theory with
a magnetic field that takes all Landau levels into account. Free energies for
atoms and matter are also calculated as well as profiles of the electron
density as a function of distance from the atomic nucleus for representative
values of the magnetic field strength, total matter density, and temperature.
The Landau shell structure, which is so prominent in cold dense matter in high
magnetic fields, is still clearly present at finite temperature as long as it
is less than approximately one tenth of the cyclotron energy. This structure is
reflected in an oscillatory behaviour of the equation of state and other
thermodynamic properties of dense matter and hence also in profiles of the
density and pressure as functions of depth in the surface layers of magnetic
neutron stars. These oscillations are completely smoothed out by thermal
effects at temperatures of the order of the cyclotron energy or higher.Comment: 37 pages, 17 figures included, submitted to Ap
Children with disturbances in sensory processing: a pilot study examining the role of the parasympathetic nervous system.
This study was a preliminary investigation of parasympathetic nervous system (PNS) functioning in children with disturbances in sensory processing. The specific aims of this study were to (1) provide preliminary data about group differences in parasympathetic functions, as measured by the vagal tone index, between children with disturbances in sensory processing and those without; (2) determine effect size and power needed for future studies; and (3) to lay the foundation for further examination of the relations of parasympathetic functioning and functional behavior in children with disturbances in sensory processing. Participants were 15 children, nine with disturbances in sensory processing and six typically developing children. Heart period data were continuously collected for a 2-minute baseline and during administration of the 15-minute Sensory Challenge Protocol, a unique laboratory protocol designed to measure sensory reactivity (Miller, Reisman, McIntosh, & Simon, 2001). Groups were compared on vagal tone index, heart period, and heart rate using two-tailed, independent sample t tests. Children with disturbances in sensory processing had significantly lower vagal tone than the typically developing sample (t(13) = 2.4, p = .05). Statistical power analysis indicated that, for future studies, a sample size of 20 in each group would yield adequate statistical power. Although the number of subjects in this pilot study is small, the results from this study support further investigations of parasympathetic functions and functional behavior in children with disturbances in sensory processing
Incidence of and risks associated with Giardia infections in herds on dairy farms in the New York City Watershed
<p>Abstract</p> <p>Background</p> <p>The primary aims of this study were to determine the incidence of <it>Giardia </it>infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of <it>Giardia </it>and <it>Cryptosporidium </it>spp. are common in this population, we also evaluated the effect of herd infection status on <it>Giardia </it>infections.</p> <p>Methods</p> <p>Farms were grouped into three cohorts based on their prior infection status with <it>Giardia </it>and/or <it>Cryptosporidium </it>spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of <it>Giardia </it>cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding.</p> <p>Results</p> <p>The majority of <it>Giardia </it>infections occurred in calves within their first 180 days of age, with the most number of calves shedding <it>Giardia </it>cysts between 11 and 20 days of age. The incidence of shedding of <it>Giardia </it>cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding <it>Giardia </it>cysts varied significantly with the age (p < 0.0001) and the season of collection (p = 0.0151 for Spring).</p> <p>Conclusion</p> <p><it>Giardia </it>infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based on changes in management practices corresponding to weather patterns of a particular season. A dairy herd's prior infection status with <it>Cryptosporidium </it>influences the likelihood of infection with <it>Giardia</it>.</p
gSLM: The Initial Steps for the Specification of a Service Management Standard for Federated e-Infrastructures
Variability in Surface BRDF at Different Spatial Scales (30 m-500 m) Over a Mixed Agricultural Landscape as Retrieved from Airborne and Satellite Spectral Measurements
Over the past decade, the role of multiangle remote sensing has been central to the development of algorithms for the retrieval of global land surface properties including models of the bidirectional reflectance distribution function (BRDF), albedo, land cover/dynamics, burned area extent, as well as other key surface biophysical quantities represented by the anisotropic reflectance characteristics of vegetation. In this study, a new retrieval strategy for fine-to-moderate resolution multiangle observations was developed, based on the operational sequence used to retrieve the Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 5 reflectance and BRDF/albedo products. The algorithm makes use of a semiempirical kernel-driven bidirectional reflectance model to provide estimates of intrinsic albedo (i.e., directional-hemispherical reflectance and bihemispherical reflectance), model parameters describing the BRDF, and extensive quality assurance information. The new retrieval strategy was applied to NASA's Cloud Absorption Radiometer (CAR) data acquired during the 2007 Cloud and Land Surface Interaction Campaign (CLASIC) over the well-instrumented Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site in Oklahoma, USA. For the case analyzed, we obtained approx.1.6 million individual surface bidirectional reflectance factor (BRF) retrievals, from nadir to 75 off-nadir, and at spatial resolutions ranging from 3 m - 500 m. This unique dataset was used to examine the interaction of the spatial and angular characteristics of a mixed agricultural landscape; and provided the basis for detailed assessments of: (1) the use of a priori knowledge in kernel-driven BRDF model inversions; (2) the interaction between surface reflectance anisotropy and instrument spatial resolution; and (3) the uncertain ties that arise when sub-pixel differences in the BRDF are aggregated to a moderate resolution satellite pixel. Results offer empirical evidence concerning the influence of scale and spatial heterogeneity in kernel-driven BRDF models; providing potential new insights into the behavior and characteristics of different surface radiative properties related to land/use cover change and vegetation structure
Land and cryosphere products from Suomi NPP VIIRS: overview and status
[1] The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument was launched in October 2011 as part of the Suomi National Polar-Orbiting Partnership (S-NPP). The VIIRS instrument was designed to improve upon the capabilities of the operational Advanced Very High Resolution Radiometer and provide observation continuity with NASA's Earth Observing System's Moderate Resolution Imaging Spectroradiometer (MODIS). Since the VIIRS first-light images were received in November 2011, NASA- and NOAA-funded scientists have been working to evaluate the instrument performance and generate land and cryosphere products to meet the needs of the NOAA operational users and the NASA science community. NOAA's focus has been on refining a suite of operational products known as Environmental Data Records (EDRs), which were developed according to project specifications under the National Polar-Orbiting Environmental Satellite System. The NASA S-NPP Science Team has focused on evaluating the EDRs for science use, developing and testing additional products to meet science data needs, and providing MODIS data product continuity. This paper presents to-date findings of the NASA Science Team's evaluation of the VIIRS land and cryosphere EDRs, specifically Surface Reflectance, Land Surface Temperature, Surface Albedo, Vegetation Indices, Surface Type, Active Fires, Snow Cover, Ice Surface Temperature, and Sea Ice Characterization. The study concludes that, for MODIS data product continuity and earth system science, an enhanced suite of land and cryosphere products and associated data system capabilities are needed beyond the EDRs currently available from the VIIRS
Use of In Situ and Airborne Multiangle Data to Assess MODIS- and Landsat-based Estimates of Surface Albedo
The quantification of uncertainty of global surface albedo data and products is a critical part of producing complete, physically consistent, and decadal land property data records for studying ecosystem change. A current challenge in validating satellite retrievals of surface albedo is the ability to overcome the spatial scaling errors that can contribute on the order of 20% disagreement between satellite and field-measured values. Here, we present the results from an uncertain ty analysis of MODerate Resolution Imaging Spectroradiometer (MODIS) and Landsat albedo retrievals, based on collocated comparisons with tower and airborne multi-angular measurements collected at the Atmospheric Radiation Measurement Program s (ARM) Cloud and Radiation Testbed (CART) site during the 2007 Cloud and Land Surface Interaction Campaign (CLAS33 IC 07). Using standard error propagation techniques, airborne measurements obtained by NASA s Cloud Absorption Radiometer (CAR) were used to quantify the uncertainties associated with MODIS and Landsat albedos across a broad range of mixed vegetation and structural types. Initial focus was on evaluating inter-sensor consistency through assessments of temporal stability, as well as examining the overall performance of satellite-derived albedos obtained at all diurnal solar zenith angles. In general, the accuracy of the MODIS and Landsat albedos remained under a 10% margin of error in the SW(0.3 - 5.0 m) domain. However, results reveal a high degree of variability in the RMSE (root mean square error) and bias of albedos in both the visible (0.3 - 0.7 m) and near-infrared (0.3 - 5.0 m) broadband channels; where, in some cases, retrieval uncertainties were found to be in excess of 20%. For the period of CLASIC 07, the primary factors that contributed to uncertainties in the satellite-derived albedo values include: (1) the assumption of temporal stability in the retrieval of 500 m MODIS BRDF values over extended periods of cloud-contaminated observations; and (2) the assumption of spatial 45 and structural uniformity at the Landsat (30 m) pixel scale
The Registry Data Warehouse in the European Reference Network for Rare Respiratory Diseases - Background, Conception and Implementation
A Window on the CP-violating Phases of MSSM from Lepton Flavor Violating Processes
It has recently been shown that by measuring the transverse polarization of
the final particles in the LFV processes , and
, one can derive information on the CP-violating phases of the
underlying theory. We derive formulas for the transverse polarization of the
final particles in terms of the couplings of the effective potential leading to
these processes. We then study the dependence of the polarizations of and
in the and on the parameters of the
Minimal Supersymmetric Standard Model (MSSM). We show that combining the
information on various observables in the and
search experiments with the information on the electric dipole moment of the
electron can help us to solve the degeneracies in parameter space and to
determine the values of certain phases.Comment: 16 pages, 8 figure
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