3,541 research outputs found
Method and system for respiration analysis Patent
Respiration analyzing method and apparatus for determining subjects oxygen consumption in aerospace environment
Light transport and general aviation aircraft icing research requirements
A short term and a long term icing research and technology program plan was drafted for NASA LeRC based on 33 separate research items. The specific items listed resulted from a comprehensive literature search, organized and assisted by a computer management file and an industry/Government agency survey. Assessment of the current facilities and icing technology was accomplished by presenting summaries of ice sensitive components and protection methods; and assessments of penalty evaluation, the experimental data base, ice accretion prediction methods, research facilities, new protection methods, ice protection requirements, and icing instrumentation. The intent of the research plan was to determine what icing research NASA LeRC must do or sponsor to ultimately provide for increased utilization and safety of light transport and general aviation aircraft
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Pollination services in the UK: how important are honeybees?
Pollination services are known to provide substantial benefits to human populations and agriculture in particular. Although many species are known to provide pollination services, honeybees (Apis mellifera) are often assumed to provide the majority of these services to agriculture. Using data from a range of secondary sources, this study assesses the importance of insect pollinated crops at regional and national scales and investigates the capacity of honeybees to provide optimal pollination services to UK agriculture. The findings indicate that insect pollinated crops have become increasingly important in UK crop agriculture and, as of 2007, accounted for 20% of UK cropland and 19% of total farmgate crop value. Analysis of honeybee hive numbers indicates that current UK populations are only capable of supplying 34% of pollination service demands even under favourable assumptions, falling from 70% in 1984. In spite of this decline, insect pollinated crop yields have risen by an average of 54% since 1984, casting doubt on long held beliefs that honeybees provide the majority of pollination services. Future land use and crop production patterns may further increase the role of pollination services to UK agriculture, highlighting the importance of measures aimed at maintaining both wild and managed species
Electron paramagnetic resonance and photochromism of in diamond
The defect in diamond formed by a vacancy surrounded by three
nearest-neighbor nitrogen atoms and one carbon atom,
, is found in of natural diamonds.
Despite being the earliest electron paramagnetic
resonance spectrum observed in diamond, to date no satisfactory simulation of
the spectrum for an arbitrary magnetic field direction has been produced due to
its complexity. In this work, is identified in
-doped synthetic diamond following irradiation and annealing.
The spin Hamiltonian parameters are revised
and used to refine the parameters for ,
enabling the latter to be accurately simulated and fitted for an arbitrary
magnetic field direction. Study of under
excitation with green light indicates charge transfer between
and . It is argued that this charge
transfer is facilitated by direct ionization of ,
an as-yet unobserved charge state of
Socio-economic inequalities in physical functioning: a comparative study of English and Greek elderly men
The associations between socio-economic position (SEP) and physical functioning have frequently been investigated but little is known about which measures of SEP are the best to use for older people. This study examined how different SEP indicators related to the physical functioning of men aged 50 or more years in England and Greece. The data derived from Wave 1 of the English Longitudinal Study of Ageing (ELSA) and from the Survey of Health, Ageing and Retirement in Europe (SHARE). Self-reported physical functioning limitations and mobility difficulties were combined and categorised into āno disabilityā, āmild disabilityā and āsevere disabilityā. The SEP indicators studied were: wealth, educational level and occupational class. The findings indicate that respondents with less wealth, fewer educational qualifications and lower occupational class were more likely to experience mild or severe physical disability than those of high SEP. When all three measures of SEP were adjusted for each other, in both samples wealth maintained a strong association with mild and severe disability, while education was associated with severe disability but only among English men. Occupational class was not strongly associated with physical disability in either case. Hence, among English and Greek older men, wealth was a more important predictor of physical functioning difficulties than either occupational class or education
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Quantifying the value of ecosystem services: a case study of honeybee pollination in the UK
There is concern that insect pollinators, such as honey bees, are currently declining in abundance, and are under serious threat from environmental changes such as habitat loss and climate change; the use of pesticides in intensive agriculture, and emerging diseases. This paper aims to evaluate how much public support there would be in preventing further decline to maintain the current number of bee colonies in the UK. The contingent valuation method (CVM) was used to obtain the willingness to pay (WTP) for a theoretical pollinator protection policy. Respondents were asked whether they would be WTP to support such a policy and how much would they pay? Results show that the mean WTP to support the bee protection policy was Ā£1.37/week/household. Based on there being 24.9 million households in the UK, this is equivalent to Ā£1.77 billion per year. This total value can show the importance of maintaining the overall pollination service to policy makers. We compare this total with estimates obtained using a simple market valuation of pollination for the UK
Socioeconomic inequalities in physical functioning: A comparative study of English and Greek elderly males
The associations between socio-economic position (SEP) and physical functioning have frequently been investigated but little is known about which measures of SEP are the best to use for older people. This study examined how different SEP indicators related to the physical functioning of men aged 50 or more years in England and Greece. The data derived from Wave 1 of the English Longitudinal Study of Ageing (ELSA) and from the Survey of Health, Ageing and Retirement in Europe (SHARE). Self-reported physical functioning limitations and mobility difficulties were combined and categorised into āno disabilityā, āmild disabilityā and āsevere disabilityā. The SEP indicators studied were: wealth, educational level and occupational class. The findings indicate that respondents with less wealth, fewer educational qualifications and lower occupational class were more likely to experience mild or severe physical disability than those of high SEP. When all three measures of SEP were adjusted for each other, in both samples wealth maintained a strong association with mild and severe disability, while education was associated with severe disability but only among English men. Occupational class was not strongly associated with physical disability in either case. Hence, among English and Greek older men, wealth was a more important predictor of physical functioning difficulties than either occupational class or education
Gelatine backing affects the performance of single-layer ballistic-resistant materials against blast fragments
Penetrating trauma by energized fragments is the most common injury from explosive devices, the main threat in the contemporary battlefield. Such devices produce projectiles dependent upon their design, including preformed fragments, casings, glass, or stones; these are subsequently energized to high velocities and cause serious injuries to the body. Current body armor focuses on the essential coverage, which is mainly the thoracic and abdominal area, and can be heavy and cumbersome. In addition, there may be coverage gaps that can benefit from the additional protection provided by one or more layers of lightweight ballistic fabrics. This study assessed the performance of single layers of commercially available ballistic protective fabrics such as KevlarĀ®, TwaronĀ®, and DyneemaĀ®, in both woven and knitted configurations. Experiments were carried out using a custom-built gas-gun system, with a 0.78-g cylindrical steel fragment simulating projectile (FSP) as the impactor, and ballistic gelatine as the backing material. FSP velocity at 50% risk of material perforation, gelatine penetration, and high-risk wounding to soft tissue, as well as the depth of penetration (DoP) against impact velocity and the normalized energy absorption were used as metrics to rank the performance of the materials tested. Additional tests were performed to investigate the effect of not including a soft-tissue simulant backing material on the performance of the fabrics. The results show that a thin layer of ballistic material may offer meaningful protection against the penetration of this FSP. Additionally, it is essential to ensure a biofidelic boundary condition as the protective efficacy of fabrics was markedly altered by a gelatine backing
All-optical hyperpolarization of electron and nuclear spins in diamond
Low thermal polarization of nuclear spins is a primary sensitivity limitation
for nuclear magnetic resonance. Here we demonstrate optically pumped
(microwave-free) nuclear spin polarization of and
in -doped diamond.
polarization enhancements up to above thermal equilibrium are observed
in the paramagnetic system . Nuclear spin polarization is
shown to diffuse to bulk with NMR enhancements of at
room temperature and at , enabling a route to
microwave-free high-sensitivity NMR study of biological samples in ambient
conditions.Comment: 5 pages, 5 figure
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