1,321 research outputs found
Angular and energy dependence of cross sections for orbital 1 excitations
The main features of the cross sections of low-lying orbital
excitations with in heavy deformed nuclei are studied in RPA on
the example of Gd. The dependence of the DWBA E2 and M1 cross sections
on the scattering angle and incident
electron energy MeV is analyzed in PWBA. The cross section is
larger for M1 than for E2 transitions at any angle if MeV. The
longitudinal (Coulomb) C2 excitation dominates the E2 response for . Only transverse M1 and E2 excitations compete for
and the former one is dominant for fm.
The M1 response is almost purely orbital up to fm even in
backward scattering. Qualitative PWBA estimates based on the -dependence of
the form factors alone are not able to predict some important features of the
cross sections stemming from the strong magnetic and orbital
character of the studied 1 excitations. The expectation for M1 over E2
dominance in backward scattering should not be extended to higher momentum
transfers and incident energies.Comment: Latex, 28 pages, 12 postscript figures included using uufile
Selection of Marker Genes Using Whole-Genome DNA Polymorphism Analysis
Molecular markers serve to assign individual samples to specific groups. Such markers should be easily identified and have a high discrimination power, being highly conserved within groups while showing sufficient variability between the groups that are to be distinguished. The availability of a large number of complete genomic sequences now enables the informed selection of genes as molecular markers based on the observed patterns of variability. We derived a new scoring system based on observed DNA polymorphic differences, and which uses the Bayes theorem as adapted by Wilcox. For validation, we applied this system to the problem of identifying individual species within a prokaryotic (Vibrio) and a eukaryotic (Diphyllobothrium) genus for validation. Top-scoring candidates genes Chromosome segregation ATPase and ATPase-subunit 6 showed better discrimination power in Vibrio and Diphyllobothrium, respectively, as compared to standard molecular markers (recA, dnaJ and atpA for Vibrio, and 18s rRNA, ITS and COX1 for Diphyllobothrium)
A design approach for integrated CMOS LC-tank oscillators using bifurcation analysis
Electrical oscillators play a decisive role in integrated transceivers for wired and wireless communication systems. In this context the study of fully integrated differential VCOs has received attention. In this paper formulas for investigations of the stability as well as the amplitude of CMOS LC tank oscillators are derived, where an overall model of nonlinear gain elements is used. By means of these results we are able to present an improved design approach which gives a deeper insight into the functionality of LC tank VCOs
Hay Quality Sensory Evaluation Form - Cereal
Hay Quality Sensory Evaluation Form – Cerea
Hay Quality Sensory Evaluation Form - Mixed Cereal/Pea or Vetch
Hay Quality Sensory Evaluation Form – Mixed Cereal/Pea or Vetc
Hay Quality Sensory Evaluation Form - Timothy; Export & Horse
Hay Quality Sensory Evaluation Form – Timothy; Export & Hors
1005-81 Myocardial Protection by Na+/H+ Exchange Inhibition in Ischemic, Reperfused Porcine Hearts
The protective effect of the Na+/H+ exchange inhibitor HOE 694 was tested in porcine hearts subjected to 45min of regional ischemia and 24 h of reperfusion. The compound (3mg/kg) was intravenously injected in 6 pigs each either 10 min before ischemia (group A) or 10 min before reperfusion (group B). Six animals served as controls. Apart from the main end-points, infarct size and regional systolic shortening, the effect of HOE 694 on global hemodynamic parameters which included coronary blood flow and coronary venous oxygen saturation was evaluated. Although the Na+IH+ exchange inhibitor did not affect global hemodynamics, preischemic treatment with HOE 694 decreased infarct size from 65±18% (control group) to 12 ± 9% (p < 0.01) and improved systolic shortening from 8 ± 6% (control group) to 28 ± 9% P < 0.02). In addition, increase in heart rate and myocardial contracture during early reperfusion were significantly attenuated in group A. Treatment of group B did not exhibit protective effects.ConclusionNa+/H+ exchange inhibition is a very protective means in myocardial ischemia and reperfusion when administered before ischemia. In this model, it was ineffective when given before reperfusion
Competing electric and magnetic excitations in backward electron scattering from heavy deformed nuclei
Important contributions to the cross sections of
low-lying orbital excitations are found in heavy deformed nuclei, arising
from the small energy separation between the two excitations with and 1, respectively. They are studied microscopically in QRPA using
DWBA. The accompanying response is negligible at small momentum transfer
but contributes substantially to the cross sections measured at for fm ( MeV)
and leads to a very good agreement with experiment. The electric response is of
longitudinal type for but becomes almost purely
transverse for larger backward angles. The transverse response
remains comparable with the response for fm
( MeV) and even dominant for MeV. This happens even at
large backward angles , where the dominance is
limited to the lower region.Comment: RevTeX, 19 pages, 8 figures included Accepted for publication in Phys
Rev
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