937 research outputs found
Engineering tests of the C-141 telescope
Data on image quality, chopper performance, and the closed-loop operation of the 91 cm telescope of the Kuiper Airborne Observatory which were obtained in September 1977 are presented
Superfluid phases of the three-species fermion gas
We discuss the zero temperature phase diagram of a dilute gas with three
fermionic species. We make use of solvable limits to conjecture the behavior of
the system in the "unitary" regions. The physics of the Thomas-Efimov effect
plays a role in these considerations. We find a rich phase diagram with
superfluid, gapless superfluid and inhomogeneous phases with different symmetry
breaking patterns. We then discuss one particular possible experimental
implementation in a system of ^6Li atoms and the possible phases arising in
this system as an external magnetic field is varied across three overlaping
Feshbach resonances. We also suggest how to experimentally distinguish the
different phases.Comment: 4 pages, 1 figure, typos corrected and references adde
Genetically Modified Striatal Astrocytes Grafted to the Brain: Pharmacological Control of an Inducible Promoter
Out-of-sequence faulting of the Jwalamukhi Thrust, India
The southernmost thrust of the Himalayan orogenic wedge that separates the
foreland from the orogen, the Main Frontal Thrust, is thought to accommodate
most of the ongoing crustal shortening in the Sub-Himalaya. Steepened
longitudinal river profile segments, terrace offsets, and back-tilted fluvial
terraces within the Kangra reentrant of the NW Sub-Himalaya suggest Holocene
activity of the Jwalamukhi Thrust (JMT) and other thrust faults that may be
associated with strain partitioning along the toe of the Himalayan wedge. To
assess the shortening accommodated by the JMT, we combine morphometric terrain
analyses with in situ 10Be-based surface-exposure dating of the deformed
terraces. Incision into upper Pleistocene sediments within the Kangra Basin
created two late Pleistocene terrace levels (T1 and T2). Subsequent early
Holocene aggradation shortly before ~10 ka was followed by episodic
reincision, which created four cut-and-fill terrace levels, the oldest of
which (T3) was formed at 10.1 ± 0.9 ka. A vertical offset of 44 ± 5 m of
terrace T3 across the JMT indicates a shortening rate of 5.6 ± 0.8 to 7.5 ±
1.1 mm a−1 over the last ~10 ka. This result suggests that thrusting along the
JMT accommodates 40–60% of the total Sub-Himalayan shortening in the Kangra
reentrant over the Holocene. We speculate that this out-of-sequence shortening
may have been triggered or at least enhanced by late Pleistocene and Holocene
erosion of sediments from the Kangra Basin
Об анатомическом строении членистостебельного растения Annulina Neuburgiana Radczenko
The purpose was to compare two approaches for the acquisition and analysis of dynamic-contrast-enhanced MRI data with respect to differences in the modelling of the arterial input-function (AIF), the dependency of the model parameters on physiological parameters and their numerical stability. Eight hundred tissue concentration curves were simulated for different combinations of perfusion, permeability, interstitial volume and plasma volume based on two measured AIFs and analysed according to the two commonly used approaches. The transfer constants (Approach 1) K (trans) and (Approach 2) k (ep) were correlated with all tissue parameters. K (trans) showed a stronger dependency on perfusion, and k (ep) on permeability. The volume parameters (Approach 1) v (e) and (Approach 2) A were mainly influenced by the interstitial and plasma volume. Both approaches allow only rough characterisation of tissue microcirculation and microvasculature. Approach 2 seems to be somewhat more robust than 1, mainly due to the different methods of CA administration
Interaction of pulses in nonlinear Schroedinger model
The interaction of two rectangular pulses in nonlinear Schroedinger model is
studied by solving the appropriate Zakharov-Shabat system. It is shown that two
real pulses may result in appearance of moving solitons. Different limiting
cases, such as a single pulse with a phase jump, a single chirped pulse,
in-phase and out-of-phase pulses, and pulses with frequency separation, are
analyzed. The thresholds of creation of new solitons and multi-soliton states
are found.Comment: 9 pages, 7 figures. Accepted to Phys. Rev. E, 200
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