Near-field radiative heat transfer between macroscopic planar surfaces

Near-field radiative heat transfer allows heat to propagate across a small vacuum gap in quantities that are several orders of magnitude greater then the heat transfer by far-field, blackbody radiation. Although heat transfer via near-field effects has been discussed for many years, experimental verification of this theory has been very limited. We have measured the heat transfer between two macroscopic sapphire plates, finding an increase in agreement with expectations from theory. These experiments, conducted near 300 K, have measured the heat transfer as a function of separation over mm to $\mu$m and as a function of temperature differences between 2.5 and 30 K. The experiments demonstrate that evanescence can be put to work to transfer heat from an object without actually touching it

Movement Patterns of Resident and Relocated Northern Bobwhites in East Texas

We compared home range sizes and movement patterns of resident and relocated northern bobwhites (Colinus virginianus) on an area managed specifically for the species in the Pineywoods of east Texas. During the winters of 1990–1992, 155 south Texas, 136 east Texas, and 139 resident bobwhites were radiomarked, released, and thereafter regularly located. Bird locations were plotted on a digitized map, and home range sizes and movement patterns of each group of birds were estimated. Resident bobwhites moved longer daily distances in March and had larger home ranges during the nesting season (May-Jul) than relocated birds (P0.05). Managers that elect to relocate northern bobwhites should consider doing so in the fall and only into habitats of ample size

Economic evaluation of physical activity interventions for type 2 diabetes management: a systematic review

Background: Economic evaluation of physical activity interventions has become an important area for policymaking considering the high costs attributable to physical inactivity. However, the evidence for such interventions targeting type 2 diabetes control is scarce. Therefore, the present study aimed to synthesize economic evaluation studies of physical activity interventions for type 2 diabetes management. Methods: A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement (PROSPERO reference number CRD42021231021). An electronic search was performed in PubMed, Web of Science, Cochrane Library and NHS Economic Evaluation Database. Studies were eligible if they included: adults with type 2 diabetes; any physical activity intervention in the community settings; an experimental or quasi-experimental design; and a parameter of economic evaluation [cost analysis of interventions, cost-effectiveness analysis (including cost-utility analysis) and cost-benefit analysis] as an outcome. Results: Ten studies were included in this review: seven were randomized controlled trials and three were quasi-experimental studies. All studies included direct costs, and four also included indirect costs. Four studies demonstrated that physical activity interventions were cost-saving, six studies showed cost-effectiveness, and two studies reported cost-utility. The estimates varied considerably across the studies with different analytical and methodological approaches. Conclusion: Overall, this systematic review found that physical activity interventions are a worth investment for type 2 diabetes management. However, comparability across interventions was limited due to heterogeneity in interventions type, design and delivery, which may explain the differences in the economic measures. © 2022 The Author(s). Published by Oxford University Press on behalf of the European Public Health Association.This work was funded by the Portuguese Foundation for Science and Technology within the scope of projects UIDB/04750/2020 and LA/P/0064/2020. Ana Barbosa was supported by the Portuguese Foundation for Science and Technology, grant number SFRH/BD/136702/2018

Food Plot Use by Juvenile Northern Bobwhites in East Texas

We examined use of spring-summer (i.e., warm-season) food plots by northern bobwhites (Colinus virginianus) with broods using radio telemetry on a 563-ha study area in Trinity County, eastern Texas, where habitat was modified to enhance it for these birds. Bobwhites from South Texas and disjunct areas of East Texas were introduced to supplement a small, resident population. All relocated and most resident bobwhites were fitted with necklace-style transmitters. Bobwhites which produced chicks were intensively radiotracked (≥3 times/day) for ≥4 weeks or until the radio-marked parent was lost. Nine hens moved their broods to food plots within an average of 2.1 days after the eggs hatched; average distance moved was 217 m. Use of food plots by 12 broods was proportionally greater than that of native vegetation (P \u3c 0.001). Food plots had lower quail-level foliage density (P = 0.015) and more arthropods (P \u3c 0.001) than native vegetation. Our results demonstrate that warm-season food plots can potentially provide brood habitat for bobwhites in eastern Texas

Food Plot Use by Juvenile Northern Bobwhites in East Texas

We examined use of spring-summer (i.e., warm-season) food plots by northern bobwhites (Colinus virginianus) with broods using radio telemetry on a 563-ha study area in Trinity County, eastern Texas, where habitat was modified to enhance it for these birds. Bobwhites from South Texas and disjunct areas of East Texas were introduced to supplement a small, resident population. All relocated and most resident bobwhites were fitted with necklace-style transmitters. Bobwhites which produced chicks were intensively radiotracked (≥3 times/day) for ≥4 weeks or until the radio-marked parent was lost. Nine hens moved their broods to food plots within an average of 2.1 days after the eggs hatched; average distance moved was 217 m. Use of food plots by 12 broods was proportionally greater than that of native vegetation (P \u3c 0.001). Food plots had lower quail-level foliage density (P = 0.015) and more arthropods (P \u3c 0.001) than native vegetation. Our results demonstrate that warm-season food plots can potentially provide brood habitat for bobwhites in eastern Texas

Greenhouse gas balance over thaw-freeze cycles in discontinuous zone permafrost

Peat in the discontinuous permafrost zone contains a globally significant reservoir of carbon that has undergone multiple permafrost-thaw cycles since the end of the mid-Holocene (~3700 years before present). Periods of thaw increase C decomposition rates which leads to the release of CO2 and CH4 to the atmosphere creating potential climate feedback. To determine the magnitude and direction of such feedback, we measured CO2 and CH4 emissions and modeled C accumulation rates and radiative fluxes from measurements of two radioactive tracers with differing lifetimes to describe the C balance of the peatland over multiple permafrost-thaw cycles since the initiation of permafrost at the site. At thaw features, the balance between increased primary production and higher CH4 emission stimulated by warmer temperatures and wetter conditions favors C sequestration and enhanced peat accumulation. Flux measurements suggest that frozen plateaus may intermittently (order of years to decades) act as CO2 sources depending on temperature and net ecosystem respiration rates, but modeling results suggest that—despite brief periods of net C loss to the atmosphere at the initiation of thaw—integrated over millennia, these sites have acted as net C sinks via peat accumulation. In greenhouse gas terms, the transition from frozen permafrost to thawed wetland is accompanied by increasing CO2 uptake that is partially offset by increasing CH4 emissions. In the short-term (decadal time scale) the net effect of this transition is likely enhanced warming via increased radiative C emissions, while in the long-term (centuries) net C deposition provides a negative feedback to climate warming

Quasilocal Energy for a Kerr black hole

The quasilocal energy associated with a constant stationary time slice of the Kerr spacetime is presented. The calculations are based on a recent proposal \cite{by} in which quasilocal energy is derived from the Hamiltonian of spatially bounded gravitational systems. Three different classes of boundary surfaces for the Kerr slice are considered (constant radius surfaces, round spheres, and the ergosurface). Their embeddings in both the Kerr slice and flat three-dimensional space (required as a normalization of the energy) are analyzed. The energy contained within each surface is explicitly calculated in the slow rotation regime and its properties discussed in detail. The energy is a positive, monotonically decreasing function of the boundary surface radius. It approaches the Arnowitt-Deser-Misner (ADM) mass at spatial infinity and reduces to (twice) the irreducible mass at the horizon of the Kerr black hole. The expressions possess the correct static limit and include negative contributions due to gravitational binding. The energy at the ergosurface is compared with the energies at other surfaces. Finally, the difficulties involved in an estimation of the energy in the fast rotation regime are discussed.Comment: 22 pages, Revtex, Alberta-Thy-18-94. (the approximations in Section IV have been improved. To appear in Phys. Rev. D

Movement Patterns of Resident and Relocated Northern Bobwhites in East Texas

We compared home range sizes and movement patterns of resident and relocated northern bobwhites (Colinus virginianus) on an area managed specifically for the species in the Pineywoods of east Texas. During the winters of 1990–1992, 155 south Texas, 136 east Texas, and 139 resident bobwhites were radiomarked, released, and thereafter regularly located. Bird locations were plotted on a digitized map, and home range sizes and movement patterns of each group of birds were estimated. Resident bobwhites moved longer daily distances in March and had larger home ranges during the nesting season (May-Jul) than relocated birds (P \u3c= 0.05). Conversely, no differences were detected among groups in mean of daily distances moved in April or dispersal during the breeding season (Mar-Jun) (P 0.05). Annual dispersal distances (x¯ = 1.43 km) of birds that survived into November were similar among groups (P \u3e 0.05). Managers that elect to relocate northern bobwhites should consider doing so in the fall and only into habitats of ample size

A Very Radio-Loud Narrow-Line Seyfert 1: PKS 2004-447

We have discovered a very radio-loud Narrow-Line Seyfert 1 candidate: PKS 2004-447. This Seyfert is consistent with the formal definition for NLS1s, although it does not have quite the same spectral features as some typical members of this subclass. Only ROSAT survey data is available at X-ray wavelengths, so it has not been possible to compare this source with other NLS1s at these wavelengths. A full comparison of this source with other members of the subclass will improve our physical understanding of NLS1s. In addition, using standard calculations, we estimate the central black hole to have a mass of $\sim 5 \times 10^6 M_{\odot}$. This does not agree with predictions in the literature, that radio-loud AGN host very massive black holes.Comment: 15 pages, 4 figures, accepted for publication in ApJ, minor typos change