10,789 research outputs found
The SU(n) invariant massive Thirring model with boundary reflection
We study the SU(n) invariant massive Thirring model with boundary reflection.
Our approach is based on the free field approach. We construct the free field
realizations of the boundary state and its dual. For an application of these
realizations, we present integral representations for the form factors of the
local operators.Comment: LaTEX2e file, 27 page
The solar wind effect on cosmic rays and solar activity
The relation of cosmic ray intensity to solar wind velocity is investigated, using neutron monitor data from Kiel and Deep River. The analysis shows that the regression coefficient of the average intensity for a time interval to the corresponding average velocity is negative and that the absolute effect increases monotonously with the interval of averaging, tau, that is, from -0.5% per 100km/s for tau = 1 day to -1.1% per 100km/s for tau = 27 days. For tau 27 days the coefficient becomes almost constant independently of the value of tau. The analysis also shows that this tau-dependence of the regression coefficiently is varying with the solar activity
Aerodynamic preliminary analysis system. Part 2: User's manual and program description
A comprehensive aerodynamic analysis program based on linearized potential theory is described. The solution treats thickness and attitude problems at subsonic and supersonic speeds. Three dimensional configurations with or without jet flaps having multiple nonplanar surfaces of arbitrary planform and open or closed slender bodies or noncircular contour are analyzed. Longitudinal and lateral-directional static and rotary derivative solutions are generated. The analysis is implemented on a time sharing system in conjunction with an input tablet digitizer and an interactive graphics input/output display and editing terminal to maximize its responsiveness to the preliminary analysis problem. Nominal case computation time of 45 CPU seconds on the CDC 175 for a 200 panel simulation indicates the program provides an efficient analysis for systematically performing various aerodynamic configuration tradeoff and evaluation studies
Effect of disorder outside the CuO planes on of copper oxide superconductors
The effect of disorder on the superconducting transition temperature
of cuprate superconductors is examined. Disorder is introduced into the cation
sites in the plane adjacent to the CuO planes of two single-layer
systems, BiSrLnCuO and
LaNdSrCuO. Disorder is controlled by changing
rare earth (Ln) ions with different ionic radius in the former, and by varying
the Nd content in the latter with the doped carrier density kept constant. We
show that this type of disorder works as weak scatterers in contrast to the
in-plane disorder produced by Zn, but remarkably reduces suggesting
novel effects of disorder on high- superconductivity.Comment: 5 pages, 5 figures, to be published in Phys. Rev. Let
Generation of Curvature Perturbations with Extra Anisotropic Stress
We study the evolution of curvature perturbations and the cosmic microwave
background (CMB) power spectrum in the presence of an hypothesized extra
anisotropic stress which might arise, for example, from the dark radiation term
in brane-world cosmology. We evolve the scalar modes of such perturbations
before and after neutrino decoupling and analyze their effects on the CMB
spectrum. A novel result of this work is that the cancellation of the neutrino
and extra anisotropic stress could lead to a spectrum of residual curvature
perturbations which is similar to the observed CMB power spectrum. This implies
a possible additional consideration in the determination of cosmological
parameters from the CMB analysis.Comment: 13 pages, 2 figures; improved discussio
Spin Fluid Dynamics Observed by Magnetic Fountain Effect and Mechano-Spin Effect in the Ferromagnetic Superfluid He A Phase
Systematic observations of the magnetically generated fountain pressure in
the superfluid He A have been carried out in a newly built apparatus
designed to reduce the effect of thermal gradients. In the same apparatus,
mechanical pumping and filtering of polarized nuclear spins were realized by
the pneumatic pumping action of an electrostatically actuated membrane. In both
experiments, the measured induced pressure was observed to decay at all
temperatures where the A phase appeared in magnetic fields up to 13 T and
liquid pressures between 1 and 29 bar. The inferred spin relaxation rate tended
to increase as the low temperature phase boundary with the A phase
(T) was approached. The increase in spin relaxation rate near T
can be explained by the presence of a minority spin condensate in the A
phase as predicted by Monien and Tewordt and by the application of the
Leggett-Takagi theory of spin relaxation in superfluid He.Comment: 12 pages, 15 figures, to appear in Physical Review
Different integration site structures between L1 protein-mediated retrotransposition in cis and retrotransposition in trans
Abstract Background Long interspersed nuclear element-1 (LINE-1 or L1) is a dominant repetitive sequence in the human genome. Besides mediating its own retrotransposition, L1 can mobilize Alu and messenger RNA (mRNA) in trans, and probably also SVA and non-coding RNA. The structures of L1 copies and trans-mobilized retrocopies are variable and can be classified into three categories: full-length; 5'-truncated; and 5'-inverted insertions. These structures may be generated by different 5' integration mechanisms. Results In this study, a method to correctly characterize insertions with short target site duplications (TSDs) is developed and extranucleotides, TSDs and microhomologies (MHs) at junctions were analysed for the three types of insertions. Only 5'-truncated L1 insertions were found to be associated with short TSDs. Both full-length and 5'-truncated retrotransposed sequences in trans, including Alu, SVA and mRNA retrocopies and also full-length and 5'-inverted L1, were not associated with short TSDs, indicating the difference of 5' attachment between retrotransposition in cis and retrotransposition in trans. Target sequence analysis suggested that short TSDs were generated in an L1 endonuclease-dependent manner. The MHs were longer for 5'-inverted L1 than for 5'-truncated L1, indicating less dependence on annealing in 5'-truncated L1 insertions. Conclusions The results suggest that insertions flanked by short TSDs occur more often coupled with the insertion of 5'-truncated L1 than with those of other types of insertions in vivo. The method used in this study can be used to characterize elements without any apparent boundary structures.</p
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