813 research outputs found
Editorial for special issue: Advances in sedentary behavior research and translation
Sedentary behaviourâessentially low energy sitting time in waking hoursâhas emerged as an important topic in public health over the past decade or so. Although Morris and colleagues [1] analysed health outcomes of active versus seated occupations over 60 years ago, it was not until studies of TV viewing in children in the 1980s [2] that researchers started to recognise âtoo much sittingâ as a potentially important health behaviour. Even then the rapid rise in the study of sedentary behaviour was not so evident until the early 2000s [3]â[5]. Studies on screen viewing (TV and computers), sitting at work and school, and sitting in cars have all emerged over this period, as well as a general recognition that high levels of sitting may have detrimental effects on health, and possibly be independent of levels of moderate-to-vigorous physical activity (MVPA). In the past 10â15 years there has been an exponential increase in papers addressing sedentary behaviour from the perspective of sitting, noting that many exercise physiologists still use the word 'sedentary' incorrectly by referring to those not meeting a criterion level of âsufficientâ physical activity
Compressive and tensile axial strain reduced critical currents in Bi-2212 conductors
Mono and multifilamentary wires of BSCCO-2212 in Ag matrix are investigated in an axial strain experiment. The superconducting samples are soldered to a substrate that is bend in order to achieve a compressive or tensile axial strain. The I/sub c/-strain dependence is measured in magnetic fields up to 16 T at 4.2 K and the strain is varied from -2% to +1.2%. In these Bi-2122 samples any strain-induced I/sub c/ reduction is irreversible. Moreover a significant rise in I/sub c/ was never observed after changing the strain. Special attention is paid to the tensile axial strain regime (0 to 0.4%). A small but significant reduction in I/sub c/ is found in this case. The strain behaviour of these wires indicates that the I/sub c/ reduction is due to fractures in the superconducting filament
The eclipsing bursting X-ray binary EXO 0748-676 revisited by XMM-Newton
The bright eclipsing and bursting low-mass X-ray binary EXO 0748-676 has been
observed at several occasions by XMM-Newton during the initial calibration and
performance verification (CAL/PV) phase. We present here the results obtained
from observations with the EPIC cameras. Apart from several type-I X-ray
bursts, the source shows a high degree of variability with the presence of soft
flares. The wide energy coverage and high sensitivity of XMM-Newton allows for
the first time a detailed description of the spectral variability.
The source is found to be the superposition of a central (~2 10^8 cm)
Comptonized emission, most probably a corona surrounding the inner edge of an
accretion disk, associated with a more extended (~3 10^10 cm) thermal halo at a
typical temperature of ~0.6 keV with an indication of non-solar abundances.
Most of the variations of the source can be accounted for by a variable
absorption affecting only the central comptonized component and reaching up to
NH ~1.3 10^23 cm^{-2}. The characteristics of the surrounding halo are found
compatible with an irradiated atmosphere of an accretion disc which intercepts
the central emission due to the system high inclination.Comment: 6 pages, 4 figures, accepted for publication in A&A Letters, XMM
special issu
Microclima: An R package for modelling meso- and microclimate
This is the author accepted manuscript. The final version is available on open access from Wiley via the DOI in this record1.Climate is of fundamental importance to the ecology and evolution of all organisms. However, studies of climateâorganism interactions usually rely on climate variables interpolated from widelyâspaced measurements or modelled at coarse resolution, whereas the conditions experienced by many organisms vary over scales from millimetres to metres.
2.To help bridge this mismatch in scale, we present models of the mechanistic processes that govern fineâscale variation in nearâground air temperature. The models are flexible (enabling application to a wide variety of locations and contexts), can be run using freely available data and are provided as an R package.
3.We apply a mesoclimate to the Lizard Peninsula in Cornwall to provide hourly estimates of air temperature at resolution of 100m for the period JanâDec 2010. A microclimate model is then applied to a one km2 region of the Lizard Peninsula, Caerthillean Valley (49.969 ÂșN, 5.215 ÂșW), to provide hourly estimates of nearâground air temperature at resolution of one m2 during May 2010.
4.Our models reveal substantial spatial variation in nearâground temperatures, driven principally by variation in topography and, at the microscale, by vegetation structure. At the mesoâscale, hours of exposure to air temperatures at one m height in excess of 25 °C ranged from 23 to 158 hours, despite this temperature never being recorded by the weather station within the study area during the study period. At the microâscale, steep southâfacing slopes with minimal vegetation cover experienced temperatures in excess of 40 °C.
5.The microclima package is flexible and efficient and provides an accurate means of modelling fineâscale variation in temperature. We also provide functions that facilitate users to obtain and process a variety of freely available datasets needed to drive the model.This research was part-funded by the European Social Fund Project 09099NCO5 and NERC NE/P016790/
Highly active iridium(I) complexes for the selective hydrogenation of carbon-carbon multiple bonds
New iridium(I) complexes, bearing a bulky NHC/phosphine ligand combination, have been established as extremely efficient hydrogenation catalysts that can be used at low catalyst loadings, and are compatible with functional groups which are often sensitive to more routinely employed hydrogenation methods
OC009âAn Assessment Of The Accuracy Of Horizon Scanning Predictions Of Medicine Use In The Scottish National Health Service
Reducing the ecological consequences of night-time light pollution: options and developments.
1. Much concern has been expressed about the ecological consequences of night-time light pollution. This concern is most often focused on the encroachment of artificial light into previously unlit areas of the night-time environment, but changes in the spectral composition, duration and spatial pattern of light are also recognized as having ecological effects.2. Here, we examine the potential consequences for organisms of five management options to reduce night-time light pollution. These are to (i) prevent areas from being artificially lit; (ii) limit the duration of lighting; (iii) reduce the 'trespass' of lighting into areas that are not intended to be lit (including the night sky); (iv) change the intensity of lighting; and (v) change the spectral composition of lighting.3. Maintaining and increasing natural unlit areas is likely to be the most effective option for reducing the ecological effects of lighting. However, this will often conflict with other social and economic objectives. Decreasing the duration of lighting will reduce energy costs and carbon emissions, but is unlikely to alleviate many impacts on nocturnal and crepuscular animals, as peak times of demand for lighting frequently coincide with those in the activities of these species. Reducing the trespass of lighting will maintain heterogeneity even in otherwise well-lit areas, providing dark refuges that mobile animals can exploit. Decreasing the intensity of lighting will reduce energy consumption and limit both skyglow and the area impacted by high-intensity direct light. Shifts towards 'whiter' light are likely to increase the potential range of environmental impacts as light is emitted across a broader range of wavelengths.4.Synthesis and applications. The artificial lightscape will change considerably over coming decades with the drive for more cost-effective low-carbon street lighting solutions and growth in the artificially lit area. Developing lighting strategies that minimize adverse ecological impacts while balancing the often conflicting requirements of light for human utility, comfort and safety, aesthetic concerns, energy consumption and carbon emission reduction constitute significant future challenges. However, as both lighting technology and understanding of its ecological effects develop, there is potential to identify adaptive solutions that resolve these conflicts.The research leading to this article has received funding from the European
Research Council under the European Unionâs Seventh Framework Programme
(FP7/2007-2013)/ERC grant agreement no. 268504
A versatile high resolution objective for imaging quantum gases
We present a high resolution objective lens made entirely from catalog
singlets that has a numerical aperture of 0.36. It corrects for aberrations
introduced by a glass window and has a long working distance of 35mm, making it
suitable for imaging objects within a vacuum system. This offers simple high
resolution imaging for many in the quantum gas community. The objective
achieves a resolution of 1.3{\mu}m at the design wavelength of 780nm, and a
diffraction-limited field of view of 360{\mu}m when imaging through a 5mm
window. Images of a resolution target and a pinhole show quantitative agreement
with the simulated lens performance. The objective is suitable for
diffraction-limited imaging on the D2 line of all the alkalis by changing only
the aperture diameter, retaining numerical apertures above 0.32. The design
corrects for window thicknesses of up to 15mm if the singlet spacings are
modified
Mammalian ranges are experiencing erosion of natural darkness
This is the final version of the article. Available from Springer Nature via the DOI in this record.The continuous increase in the intensity and extent of anthropogenic artificial light has significantly shaped Earth's nighttime environment. This environmental change has effects across the natural world, with consequences for organismal physiology and behaviour and the abundances and distributions of species. Here, we evaluate for the first time the relations between the spatio-temporal patterns of anthropogenic nighttime light and the distribution of terrestrial mammals, one of the most endangered species groups and one that expresses varying time partitioning strategies. Using descriptive statistics, trend tests and spatial prioritization analysis we show that in most places on earth there is a terrestrial mammal species whose range is experiencing detectable artificial light. For most species this tends only to be for small parts of their range, and those affected across large parts are typically rare. Over time (1992-2012), an increase in mean light intensity was found for the ranges of the majority of species, with very few experiencing a decrease. Moreover, nocturnal species are more likely to experience an increase in light within their ranges. This is of conservation concern as many terrestrial mammals are nocturnal and therefore often particularly vulnerable to a pressure such as artificial light at night.The research leading to this paper has received funding from the European Research Council under the European Unionâs Seventh Framework Programme (FP7/2007â2013)/ERC grant agreement no. 268504 to K.J.G
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