2,064 research outputs found
A Dual Read-Out Assay to Evaluate the Potency of Compounds Active against Mycobacterium tuberculosis
PMCID: PMC3617142This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Numerical simulation of thermally induced near-surface flows over Martian terrain
Numerical simulations of the Martian near-surface wind regime using a mesoscale atmospheric model have shown that the thermally induced near-surface winds are analogous to terrestrial circulations. In particular, katabatic wind displays a striking similarity to flow observed over Antarctica. Introduction of solar radiation strongly perturbs the slope flows; anabatic conditions develop in middle to high latitudes during the daytime hours due to the solar heating of the sloping terrain. There appears to be a rapid transition from the katabatic to the anabatic flow regimes, emphasizing the primary importance of radiative exchanges at the surface in specifying the horizontal pressure gradient force
Recommended cereal varieties : 1969
Cereal varieties widely recommended for growing in 1969 are Gamenya and Falcon wheats, Dampier and Beecher barleys and Swan oats.
Other varieties include the new wheat Darkan, which is recommended only for the higher rainfall areas, the rust resistant wheats Mengavi and Gamut, and Irwin oats for late sowing in northeastern districts
Asymmetric Fermi superfluid with different atomic species in a harmonic trap
We study the dilute fermion gas with pairing between two species and unequal
concentrations in a harmonic trap using the mean field theory and the local
density approximation. We found that the system can exhibit a superfluid shell
structure sandwiched by the normal fermions. This superfluid shell structure
occurs if the mass ratio is larger then certain critical value which increases
from the weak-coupling BCS region to the strong-coupling BEC side. In the
strong coupling BEC regime, the radii of superfluid phase are less sensitive to
the mass ratios and are similar to the case of pairing with equal masses.
However, the lighter leftover fermions are easier to mix with the superfluid
core than the heavier ones. A partially polarized superfluid can be found if
the majority fermions are lighter, whereas phase separation is still found if
they are heavier.Comment: 12 pages, 7 figure
Pairing in spin polarized two-species fermionic mixtures with mass asymmetry
We discuss on the pairing mechanism of fermions with mismatch in their fermi
momenta due to a mass asymmetry. Using a variational ansatz for the ground
state we also discuss the BCS -BEC crossover of this system. It is shown that
the breached pairing solution with a single fermi surface is stable in the BEC
regime. We also include the temperatures effect on the fermion pairing within
an approximation that is valid for temperatures much below the critical
temperature.Comment: 8 pages and 6 figures, few typos corrected, version to appear in EPJ
Coupled-cluster theory of a gas of strongly-interacting fermions in the dilute limit
We study the ground-state properties of a dilute gas of strongly-interacting
fermions in the framework of the coupled-cluster expansion (CCE). We
demonstrate that properties such as universality, opening of a gap in the
excitation spectrum and applicability of s-wave approximations appear naturally
in the CCE approach. In the zero-density limit, we show that the ground-state
energy density depends on only one parameter which in turn may depend at most
on the spatial dimensionality of the system.Comment: 7 figure
Non-saturating magnetoresistance of inhomogeneous conductors: comparison of experiment and simulation
The silver chalcogenides provide a striking example of the benefits of
imperfection. Nanothreads of excess silver cause distortions in the current
flow that yield a linear and non-saturating transverse magnetoresistance (MR).
Associated with the large and positive MR is a negative longitudinal MR. The
longitudinal MR only occurs in the three-dimensional limit and thereby permits
the determination of a characteristic length scale set by the spatial
inhomogeneity. We find that this fundamental inhomogeneity length can be as
large as ten microns. Systematic measurements of the diagonal and off-diagonal
components of the resistivity tensor in various sample geometries show clear
evidence of the distorted current paths posited in theoretical simulations. We
use a random resistor network model to fit the linear MR, and expand it from
two to three dimensions to depict current distortions in the third (thickness)
dimension. When compared directly to experiments on AgSe and
AgTe, in magnetic fields up to 55 T, the model identifies
conductivity fluctuations due to macroscopic inhomogeneities as the underlying
physical mechanism. It also accounts reasonably quantitatively for the various
components of the resistivity tensor observed in the experiments.Comment: 10 pages, 7 figure
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Criticality analysis of selected Saxton Plutonium Program experiments using WIMS-D4M and DIF3D
The Saxton critical experiments were simulated with homogenized region, multigroup cross sections from the WIMS-D4M lattice physics code (ENDF/B-V library) and the diffusion code, DIF3D. The simulations were focused on assessing the codes` capabilities, including the different cell models available in WIMS-D4M. The accuracy of the core power distributions obtained with DIF3D has also been assessed. The number of experiments and their variety was used to obtain statistical parameters that allow a quantitative discussion of the assessment of the methodology
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