1,724 research outputs found
Food Aid as Surplus Disposal? The WTO, Export Competition Disciplines and the Disposition of Food Aid
The empirical investigation suggests that there exists an endogenous relationship between subsidy/credit shipments and food aid for wheat in the US. The empirical VAR demonstrates a contemporaneous increase in food aid shipments as alternative vents constrict. This result suggests that a trade agreement that disciplines export subsidies and credits may put upward pressure on food aid shipments as agricultural exporters vent the pressure of their domestic surpluses. The empirical results suggest that in the US wheat market the effects are not large. The same phenomenon has been noted in the case of skim milk powder by Margulis; skim milk powder would provide another interesting empirical case, were the data available.Food Security and Poverty,
Food Aid as Surplus Disposal? The WTO, Export Competition Disciplines and the Disposition of Food Aid
Food Security and Poverty, International Relations/Trade,
A review of mushrooms as a potential source of dietary vitamin D
When commonly consumed mushroom species are exposed to a source of ultraviolet (UV) radiation, such as sunlight or a UV lamp, they can generate nutritionally relevant amounts of vitamin D. The most common form of vitamin D in mushrooms is D2, with lesser amounts of vitamins D3 and D4, while vitamin D3 is the most common form in animal foods. Although the levels of vitamin D2 in UV-exposed mushrooms may decrease with storage and cooking, if they are consumed before the ‘best-before’ date, vitamin D2 level is likely to remain above 10 µg/100 g fresh weight, which is higher than the level in most vitamin D-containing foods and similar to the daily requirement of vitamin D recommended internationally. Worldwide mushroom consumption has increased markedly in the past four decades, and mushrooms have the potential to be the only non-animal, unfortified food source of vitamin D that can provide a substantial amount of vitamin D2 in a single serve. This review examines the current information on the role of UV radiation in enhancing the concentration of vitamin D2 in mushrooms, the effects of storage and cooking on vitamin D2 content, and the bioavailability of vitamin D2 from mushrooms
Drivers of transfusion decision making and quality of the evidence in orthopedic surgery: a systematic review of the literature
Development and acceptability of four protein-fortified foods to supplement the Iranian school lunch program
Magnetic Tunnel Junction Random Number Generators Applied to Dynamically Tuned Probability Trees Driven by Spin Orbit Torque
Perpendicular magnetic tunnel junction (pMTJ)-based true-random number
generators (RNG) can consume orders of magnitude less energy per bit than CMOS
pseudo-RNG. Here, we numerically investigate with a macrospin
Landau-Lifshitz-Gilbert equation solver the use of pMTJs driven by spin-orbit
torque to directly sample numbers from arbitrary probability distributions with
the help of a tunable probability tree. The tree operates by dynamically
biasing sequences of pMTJ relaxation events, called 'coinflips', via an
additional applied spin-transfer-torque current. Specifically, using a single,
ideal pMTJ device we successfully draw integer samples on the interval 0,255
from an exponential distribution based on p-value distribution analysis. In
order to investigate device-to-device variations, the thermal stability of the
pMTJs are varied based on manufactured device data. It is found that while
repeatedly using a varied device inhibits ability to recover the probability
distribution, the device variations average out when considering the entire set
of devices as a 'bucket' to agnostically draw random numbers from. Further, it
is noted that the device variations most significantly impact the highest level
of the probability tree, iwth diminishing errors at lower levels. The devices
are then used to draw both uniformly and exponentially distributed numbers for
the Monte Carlo computation of a problem from particle transport, showing
excellent data fit with the analytical solution. Finally, the devices are
benchmarked against CMOS and memristor RNG, showing faster bit generation and
significantly lower energy use.Comment: 10 pages, 8 figures, 2 table
Sir John Cornforth AC CBE FRS: his synthetic work
Sir John Cornforth’s work on the synthesis of cholesterol and penicillamine, on the chemistry of oxazoles, the stereochemistry of the synthesis of alkenes, the synthesis of abscisic acid and of dibenzophospholes as mimics of enzyme action, is reviewed
Performance of the Gemini Planet Imager Non-Redundant Mask and spectroscopy of two close-separation binaries HR 2690 and HD 142527
The Gemini Planet Imager (GPI) contains a 10-hole non-redundant mask (NRM),
enabling interferometric resolution in complement to its coronagraphic
capabilities. The NRM operates both in spectroscopic (integral field
spectrograph, henceforth IFS) and polarimetric configurations. NRM observations
were taken between 2013 and 2016 to characterize its performance. Most
observations were taken in spectroscopic mode with the goal of obtaining
precise astrometry and spectroscopy of faint companions to bright stars. We
find a clear correlation between residual wavefront error measured by the AO
system and the contrast sensitivity by comparing phase errors in observations
of the same source, taken on different dates. We find a typical 5-
contrast sensitivity of at . We explore the
accuracy of spectral extraction of secondary components of binary systems by
recovering the signal from a simulated source injected into several datasets.
We outline data reduction procedures unique to GPI's IFS and describe a newly
public data pipeline used for the presented analyses. We demonstrate recovery
of astrometry and spectroscopy of two known companions to HR 2690 and HD
142527. NRM+polarimetry observations achieve differential visibility precision
of in the best case. We discuss its limitations on
Gemini-S/GPI for resolving inner regions of protoplanetary disks and prospects
for future upgrades. We summarize lessons learned in observing with NRM in
spectroscopic and polarimetric modes.Comment: Accepted to AJ, 22 pages, 14 figure
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