12,469 research outputs found
Evaluation and Management of Sleep Disorders in the Hand Surgery Patient.
Despite posing a significant public health threat, sleep disorders remain poorly understood and often underdiagnosed and mismanaged. Although sleep disorders are seemingly unrelated, hand surgeons should be mindful of these because numerous conditions of the upper extremity have known associations with sleep disturbances that can adversely affect patient function and satisfaction. In addition, patients with sleep disorders are at significantly higher risk for severe, even life-threatening medical comorbidities, further amplifying the role of hand surgeons in the recognition of this condition
Positive and Negative Effects of Addition of Organic Carbon and Nitrogen for Management of Sulfuric Soil Material Acidity under General Soil Use Conditions
This paper reports the findings of two studies conducted to investigate the effects on pH, Eh and sulfate content of sulfuric soil material of acid sulfate soil following the addition of organic carbon and nitrogen. The first study compared the responses to simple carbon sources (glucose, sodium acetate and molasses) with complex organic matter in the form of chopped Phragmites. The second experiment considered the effect of nitrogen by testing organic matter with varying nitrogen content. The results of the first study showed that the changes in Eh and sulfate contents induced by these treatments mirrored the changes in pH, the highest change being only 5.6 units induced by sodium acetate. These results showed that organic carbon alone was ineffective in treating sulfuric soil material acidity, and that nitrogen was needed. Lucerne hay which had the highest nitrogen content produced the largest increase in pH by 4.2 units, and the changes of pea straw and wheat straw was 3.2 units. It was proposed that the alkalinising effect of the treatments was mediated by anaerobic microbial metabolism which required sources of nitrogen as well as organic carbon. The changes in soil redox conditions by -150 mV measured indicated that sulfur-reducing bacteria induced the changes in Eh, which caused pH to increase and sulfate content to decrease in comparison with nitrate-reducing bacteria. The findings of these studies have implications for management of sulfuric soil material acidity
Mirage Torsion
Z_NxZ_M orbifold models admit the introduction of a discrete torsion phase.
We find that models with discrete torsion have an alternative description in
terms of torsionless models. More specifically, discrete torsion can be 'gauged
away' by changing the shifts by lattice vectors. Similarly, a large class of
the so-called generalized discrete torsion phases can be traded for changing
the background fields (Wilson lines) by lattice vectors. We further observe
that certain models with generalized discrete torsion are equivalent to
torsionless models with the same gauge embedding but based on different
compactification lattices. We also present a method of classifying heterotic
Z_NxZ_M orbifolds.Comment: 26 pages, 3 figures, v2: matches version published in JHE
Violation from String Theory
We identify a natural way to embed symmetry and its violation
in string theory. The symmetry of the low energy effective
theory is broken by the presence of heavy string modes.
violation is the result of an interplay of and flavor symmetry.
violating decays of the heavy modes could originate a
cosmological matter-antimatter asymmetry.Comment: 7 pages, 4 figure
A note on discrete R symmetries in Z6-II orbifolds with Wilson lines
We re-derive the R symmetries for the Z6-II orbifold with non-trivial Wilson
lines and find expressions for the R charges which differ from those in the
literature.Comment: 13 pages, 3 figure
Self-Sustaining Oscillations in Complex Networks of Excitable Elements
Random networks of symmetrically coupled, excitable elements can
self-organize into coherently oscillating states if the networks contain loops
(indeed loops are abundant in random networks) and if the initial conditions
are sufficiently random. In the oscillating state, signals propagate in a
single direction and one or a few network loops are selected as driving loops
in which the excitation circulates periodically. We analyze the mechanism,
describe the oscillating states, identify the pacemaker loops and explain key
features of their distribution. This mechanism may play a role in epileptic
seizures.Comment: 5 pages, 4 figures included, submitted to Phys. Rev. Let
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