8,517 research outputs found
An overview of the focus of the International Gap Junction Conference 2017 and Future Perspectives
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REMOVED: Microscale Electrodialysis: Concentration Profiling and Vortex Visualization
This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been removed at the request of the Executive Publisher.This article has been removed because it was published without the permission of the author(s)
Modeling the X-rays Resulting from High Velocity Clouds
With the goal of understanding why X-rays have been reported near some high
velocity clouds, we perform detailed 3 dimensional hydrodynamic and
magnetohydrodynamic simulations of clouds interacting with environmental gas
like that in the Galaxy's thick disk/halo or the Magellanic Stream. We examine
2 scenarios. In the first, clouds travel fast enough to shock-heat warm
environmental gas. In this scenario, the X-ray productivity depends strongly on
the speed of the cloud and the radiative cooling rate. In order to shock-heat
environmental gas to temperatures of > or = 10^6 K, cloud speeds of > or = 300
km/s are required. If cooling is quenched, then the shock-heated ambient gas is
X-ray emissive, producing bright X-rays in the 1/4 keV band and some X-rays in
the 3/4 keV band due to O VII and other ions. If, in contrast, the radiative
cooling rate is similar to that of collisional ionizational equilibrium plasma
with solar abundances, then the shocked gas is only mildly bright and for only
about 1 Myr. The predicted count rates for the non-radiative case are bright
enough to explain the count rate observed with XMM-Newton toward a Magellanic
Stream cloud and some enhancement in the ROSAT 1/4 keV count rate toward
Complex C, while the predicted count rates for the fully radiative case are
not. In the second scenario, the clouds travel through and mix with hot ambient
gas. The mixed zone can contain hot gas, but the hot portion of the mixed gas
is not as bright as those from the shock-heating scenario.Comment: 15 pages, 9 figures, 1 table. Accepted for publication in the
Astrophysical Journa
Matrix exponential via Clifford algebras
We use isomorphism between matrix algebras and simple orthogonal
Clifford algebras \cl(Q) to compute matrix exponential of a real,
complex, and quaternionic matrix A. The isomorphic image in
\cl(Q), where the quadratic form has a suitable signature is
exponentiated modulo a minimal polynomial of using Clifford exponential.
Elements of \cl(Q) are treated as symbolic multivariate polynomials in
Grassmann monomials. Computations in \cl(Q) are performed with a Maple
package `CLIFFORD'. Three examples of matrix exponentiation are given
Growth, Condition, and Trophic Relations of Stocked Trout in Southern Appalachian Mountain Streams
Stream trout fisheries are among the most popular and valuable in the United States, but many are dependent on hatcheries to sustain fishing and harvest. Thus, understanding the ecology of hatcheryâreared trout stocked in natural environments is fundamental to management. We evaluated the growth, condition, and trophic relations of Brook Trout Salvelinus fontinalis, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss that were stocked in southern Appalachian Mountain streams in western North Carolina. Stocked and wild (naturalized) trout were sampled over time (monthly; September 2012âJune 2013) to compare condition and diet composition and to evaluate temporal dynamics of trophic position with stable isotope analysis. Relative weights (Wr) of stocked trout were inversely associated with their stream residence time but were consistently higher than those of wild trout. Weight loss of harvested stocked trout was similar among species and sizes, but fish stocked earlier lost more weight. Overall, 40% of 141 stomachs from stocked trout were empty compared to 15% of wild trout stomachs (N = 26). We identified a much higher rate of piscivory in wild trout (18 times that of stocked trout), and wild trout were 4.3 times more likely to consume gastropods relative to stocked trout. Hatcheryâreared trout were isotopically similar to coâoccurring wild fish for both δ13C and δ15N values but were less variable than wild trout. Differences in sulfur isotope ratios (δ34S) between wild and hatcheryâreared trout indicated that the diets of wild fish were enriched in δ34S relative to the diets of hatcheryâreared fish. Although hatcheryreared trout consumed prey items similar to those of wild fish, differences in consumption or behavior (e.g., reduced feeding) may have resulted in lower condition and negative growth. These findings provide critical insight on the trophic dynamics of stocked trout and may assist in developing and enhancing stream trout fisheries
Inappropriate electrolyte repletion for patients undergoing endoscopic procedures
At Thomas Jefferson University Hospital (TJUH), there has been a perceived necessity among housestaff and fellows to routinely check and replete serum potassium and magnesium for inpatients prior to endoscopic procedures In addition, there was an unwritten policy that these electrolytes needed to be aggressively repleted, with a goal potassium above 4.0 and magnesium above 2.0 Contributing factors include absence of clear policy, fear of adverse outcomes during procedures, and fear of delay of procedures leading to increased hospital stay This practice has led to unwarranted lab draws, costs of lab tests and electrolyte riders, and possible delayed procedures
Goals Clarify policies regarding electrolyte repletion Determine frequency of inappropriate electrolyte checking and repletion Determine monetary cost of this action Decrease frequency of inappropriate electrolyte lab check and repletionhttps://jdc.jefferson.edu/patientsafetyposters/1023/thumbnail.jp
Microwave curing of carbon-epoxy composites: Penetration depth and material characterisation
Microwave heating has several major advantages over conventional conductive heating when used to cure carbonâepoxy composites, especially in speed of processing. Despite this and many other well-known advantages, microwave heating of carbonâepoxy composites has not taken off in industry, or even academia, due to the problems associated with microwave energy distribution, arcing, tool design and (ultimately) part quality and consistency, thus leading to a large scepticism regarding the technique/technology for heating such type of materials. This paper presents some evidence which suggests that with the correct hardware and operating procedure/methodology, consistent and high quality carbonâepoxy laminates can be produced, with the possibility of scaling up the process, as demonstrated by the micro- and macro-scale mechanical test results. Additionally, the author proposes a methodology to practically measure the maximum microwave penetration depth of a carbonâepoxy composite material
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