9,255 research outputs found
Pulsed plasmoid electric propulsion
A method of electric propulsion is explored where plasmoids such as spheromaks and field reversed configurations (FRC) are formed and then allowed to expand down a diverging conducting shell. The plasmoids contain a toroidal electric current that provides both heating and a confining magnetic field. They are free to translate because there are no externally supplied magnetic fields that would restrict motion. Image currents in the diverging conducting shell keep the plasmoids from contacting the wall. Because these currents translate relative to the wall, losses due to magnetic flux diffusion into the wall are minimized. During the expansion of the plasma in the diverging cone, both the inductive and thermal plasma energy are converted to directed kinetic energy producing thrust. Specific impulses can be in the 4000 to 20000 sec range with thrusts from 0.1 to 1000 Newtons, depending on available power
Transport phenomenology for a holon-spinon fluid
We propose that the normal-state transport in the cuprate superconductors can
be understood in terms of a two-fluid model of spinons and holons. In our
scenario, the resistivity is determined by the properties of the holons while
magnetotransport involves the recombination of holons and spinons to form
physical electrons. Our model implies that the Hall transport time is a measure
of the electron lifetime, which is shorter than the longitudinal transport
time. This agrees with our analysis of the normal-state data. We predict a
strong increase in linewidth with increasing temperature in photoemission. Our
model also suggests that the AC Hall effect is controlled by the transport
time.Comment: 4 pages, 1 postscript figure. Uses RevTeX, epsf, multico
Coexistence of a triplet nodal order-parameter and a singlet order-parameter at the interfaces of ferromagnet-superconductor Co/CoO/In junctions
We present differential conductance measurements of Cobalt / Cobalt-Oxide /
Indium planar junctions, 500nm x 500nm in size. The junctions span a wide range
of barriers, from very low to a tunnel barrier. The characteristic conductance
of all the junctions show a V-shape structure at low bias instead of the
U-shape characteristic of a s-wave order parameter. The bias of the conductance
peaks is, for all junctions, larger than the gap of indium. Both properties
exclude pure s-wave pairing. The data is well fitted by a model that assumes
the coexistence of s-wave singlet and equal spin p-wave triplet fluids. We find
that the values of the s-wave and p-wave gaps follow the BCS temperature
dependance and that the amplitude of the s-wave fluid increases with the
barrier strength.Comment: 5 pages, Accepted to Phys. Rev.
Intracerebral hemorrhage for the palliative care provider: what you need to know.
Intracerebral hemorrhage (ICH) makes up 10%-30% of all strokes. Palliative care providers are often asked to get involved with ICH cases to aid with development of short-term and long-term goals. Prognosis can be calculated using the ICH score (based on Glasgow Coma Score score, ICH volume, presence of intraventricular hemorrhage, age, and location of origin) or the Essen score (based on age, NIH Stroke Scale [NIHSS], and level of consciousness). Do-not-resuscitate (DNR) status is important to discuss with families. Expert consensus states DNR is appropriate if the patient has two of the following: severe stroke, life-threatening brain damage, or significant comorbidities. The process of withdrawing ventilatory support can differ greatly from that of a medical intensive care unit (ICU) patient. Most ICH patients die within 24 hours following extubation. Symptoms of dyspnea and pain warrant use of opioids before and after terminal extubation. In addition, treating death rattle and postextubation stridor are important interventions. Family meetings are a vital intervention to help explain prognosis, establish a plan of care, and to get all family members on the same page. Family meetings can have a rapid effect, with 66% of families opting for withdrawal of life support to decide within 24 hours of such a meeting
CHARACTERISTICS OF MANGROVE DIAMONDBACK TERRAPINS (MALACLEMYS TERRAPIN RHIZOPHORARUM) INHABITING ALTERED AND NATURAL MANGROVE ISLANDS
The Mangrove Diamondback Terrapin, (Malaclemys terrapin rhizophorarum) is dependent on a very broad array of the services provided by the mangrove ecosystem. We sought to evaluate both the turtles and their habitat by an integrated assessment of physical, chemical, and physiological parameters. Extreme site fidelity of the turtles to mangrove habitat was evident along with a strong female biased sex ratio. We provide blood serum values and microbial cultures as baselines from these turtles in the wild. Salmonella sp., a potentially zoonotic pathogen, was isolated from one female. Ultimately, the health of these turtle populations may be reflective of the integrity of the mangrove system on which they depend
EFFECTS OF FORAGE QUALITY RESTRICTIONS ON OPTIMAL PRODUCTION SYSTEMS DETERMINED BY LINEAR PROGRAMMING
Livestock Production/Industries,
Analysis of Pellet Ablation with Atomic Processes
A new type of a magnetohydrodynamics (MHD) code applicable to solid, liquid and gas states, “CAP” has been developed in order to investigate ablation process of a pellet with ato mic processes in hot plasmas. One of the most important features of the code is to be able to treat re cession of the pellet surface by ablation without any artificial boundary condition between the pellet an d ablation cloud. A region excluding a magnetic field is induced because the magnetic pressure is overcome by the ablation pressure. It is found that a stationary shock wave is driven by ionization
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