7,006 research outputs found
Instrument support with precise lateral adjustment Patent
Centering device with ultrafine adjustment for use with roundness measuring apparatu
A proposed neutral line signature
An identifying signature is proposed for the existence and location of the neutral line in the magnetotail. The signature, abrupt density, and temperature changes in the Earthtail direction, was first discovered in test particle simulations. Such temperature variations have been observed in ISEE data (Huang et. al. 1992), but their connection to the possible existence of a neutral line in the tail has not yet been established. The proposed signature develops earlier than the ion velocity space ridge of Martin and Speiser (1988), but can only be seen by spacecraft in the vicinity of the neutral line, while the latter can locate a neutral line remotely
Origin of Lagrangian Intermittency in Drift-Wave Turbulence
The Lagrangian velocity statistics of dissipative drift-wave turbulence are
investigated. For large values of the adiabaticity (or small collisionality),
the probability density function of the Lagrangian acceleration shows
exponential tails, as opposed to the stretched exponential or algebraic tails,
generally observed for the highly intermittent acceleration of Navier-Stokes
turbulence. This exponential distribution is shown to be a robust feature
independent of the Reynolds number. For small adiabaticity, algebraic tails are
observed, suggesting the strong influence of point-vortex-like dynamics on the
acceleration. A causal connection is found between the shape of the probability
density function and the autocorrelation of the norm of the acceleration
A relativistically covariant version of Bohm's quantum field theory for the scalar field
We give a relativistically covariant, wave-functional formulation of Bohm's
quantum field theory for the scalar field based on a general foliation of
space-time by space-like hypersurfaces. The wave functional, which guides the
evolution of the field, is space-time-foliation independent but the field
itself is not. Hence, in order to have a theory in which the field may be
considered a beable, some extra rule must be given to determine the foliation.
We suggest one such rule based on the eigen vectors of the energy-momentum
tensor of the field itself.Comment: 1 figure. Submitted to J Phys A. 20/05/04 replacement has additional
references and a few minor changes made for clarity. Accepted by J Phys
Identification of a Candidate CD5 Homologue in the Amphibian Xenopus laevis
We identified a novel T cell Ag in the South African clawed toad (Xenopus laevis) by a mAb designated 2B1. This Ag is present in relatively high levels on most thymocytes, approximately 65% of splenocytes, 55% of PBL, and 65% of intestinal lymphocytes, but is rarely seen on IgM+ B cells in any of these tissues. Lymphocytes bearing the 2B1 Ag proliferate in response to stimulation with Con A or PHA, whereas the 2B1- lymphocytes are reactive to LPS. Biochemical analysis indicates that this Ag is a differentially phosphorylated glycoprotein of 71 to 82 kDa. The protein core of 64 kDa bears both N- and O-linked carbohydrate side chains. The amino-terminal protein sequence of the 2B1 Ag shares significant homology with both the macrophage scavenger receptor type 1 motif and the mammalian CD5/CD6 family. The biochemical characteristics and cellular distribution of the 2B1 Ag suggest that it represents the CD5 homologue in X. laevis. While T cells constitutively express this highly conserved molecule, Xenopus B cells acquire the CD5 homologue only when they are stimulated in the presence of T cell
Cryotherapy of Liver Tumours–A Practical Guide
The use of cryotherapy for the treatment of some unresectable liver tumours has been clearly
established as a therapeutic option. Intra-operative ultrasound has enhanced the process by enabling
the surgeon to identify hepatic lesions and to allow visualisation of the freezing process to ensure that
the cryolesion will include the tumour mass. The purpose of this paper is to provide a practical guide to
surgeons who wish to perform cryotherapy of liver tumours. Patient selection and anaesthetic
considerations are important. The surgeon should be able to deal with the complications of
cryotherapy, particularly the intra-operative haemorrhage which may arise from cracking of the
hepatic parenchyma as the iceball thaws. Follow-up is based on tumour marker assay and imaging of
the liver and repeat cryotherapy can be considered for selected cases
Transition from resistive-6 to ηi-driven turbulence in stellarator systems
B.‐G. Hong et al., Physics of Fluids B: Plasma Physics 3, 1638 (1991) https://doi.org/10.1063/1.85968
Feasibility and systems definition study for Microwave Multi-Application Payload (MMAP)
Work completed on three Shuttle/Spacelab experiments is examined: the Adaptive Multibeam Phased Array Antenna (AMPA) Experiment, Electromagnetic Environment Experiment (EEE) and Millimeter Wave Communications Experiment (MWCE). Results included the definition of operating modes, sequence of operation, radii of operation about several ground stations, signal format, foot prints of typical orbits and preliminary definition of ground and user terminals. Conceptual hardware designs, Spacelab interfaces, data handling methods, experiment testing and verification studies were included. The MWCE-MOD I was defined conceptually for a steerable high gain antenna
Book Reviews
Reviews of the following books: The First Century: A History of the University of Maine, 1865-1965 by David C. Smith; Suthin (It\u27s the Opposite of Nothin\u27): An Oral History of Grover Morrison\u27s Woods Operation at Little Musquah Lake, 1945-1947 by Stephen Ballew, Joan Brooks, Dona Brotz and Edward Ives; I\u27m a Man That Works : The Biography of Don Mitchell of Merrill, Maine by Roger G. Mitchell; Remarks on My Life Per Me Hezekiah Prince, 1786-1792 edited by Sally Hill and Arthur Spear; Two Feet Between the Rails, Vol. I: The Early Years by Robert C. Jones; The History of Mercer, Maine by Lessie B. Loude
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