288 research outputs found
Effects of the large gluon polarization on and J/ productions at polarized ep and pp collisions
The recent SMC data of are reproduced with the large polarized
gluons. To study further the polarized gluon distribution in a proton, we
calculate the spin--dependent differential cross section for J/
leptoproductions and the two--spin asymmetry for J/ hadroproductions. Its
experimental implication is discussed.Comment: LaTeX file, 10 pages+6 figures available upon request, KOBE-FHD-93-0
Universal Behavior of Correlations between Eigenvalues of Random Matrices
The universal connected correlations proposed recently between eigenvalues of
unitary random matrices is examined numerically. We perform an ensemble average
by the Monte Carlo sampling. Although density of eigenvalues and a bare
correlation of the eigenvalues are not universal, the connected correlation
shows a universal behavior after smoothing.Comment: ISSP-September-199
Law of addition in random matrix theory
We discuss the problem of adding random matrices, which enable us to study
Hamiltonians consisting of a deterministic term plus a random term. Using a
diagrammatic approach and introducing the concept of ``gluon connectedness," we
calculate the density of energy levels for a wide class of probability
distributions governing the random term, thus generalizing a result obtained
recently by Br\'ezin, Hikami, and Zee. The method used here may be applied to a
broad class of problems involving random matrices.Comment: 17 pages, Latex with special macro appended, hard figs available
from: [email protected]
Correlations between eigenvalues of large random matrices with independent entries
We derive the connected correlation functions for eigenvalues of large
Hermitian random matrices with independently distributed elements using both a
diagrammatic and a renormalization group (RG) inspired approach. With the
diagrammatic method we obtain a general form for the one, two and three-point
connected Green function for this class of ensembles when matrix elements are
identically distributed, and then discuss the derivation of higher order
functions by the same approach. Using the RG approach we re-derive the one and
two-point Green functions and show they are unchanged by choosing certain
ensembles with non-identically distributed elements. Throughout, we compare the
Green functions we obtain to those from the class of ensembles with unitary
invariant distributions and discuss universality in both ensemble classes.Comment: 23 pages, RevTex, hard figures available from [email protected]
Delta s density in a proton and unpolarized lepton - polarized proton scatterings
It is shown that the parity--violating deep--inelastic scatterings of
unpolarized charged leptons on polarized protons, , could provide a sensitive
test for the behavior and magnitude of the polarized strange--quark density in
a proton. Below charm threshold these processes are also helpful to uniquely
determine the magnitude of individual polarized parton distributions.Comment: LaTeX file, 12 pages+4 fiigures not included (available upon request
Correlation functions of eigenvalues of multi-matrix models, and the limit of a time dependent matrix
We consider the correlation functions of eigenvalues of a unidimensional
chain of large random hermitian matrices. An asymptotic expression of the
orthogonal polynomials allows to find new results for the correlations of
eigenvalues of different matrices of the chain. Eventually, we consider the
limit of the infinite chain of matrices, which can be interpreted as a time
dependent one-matrix model, and give the correlation functions of eigenvalues
at different times.Comment: Tex-Harvmac, 27 pages, submitted to Journ. Phys.
Indigenous evolution of Plasmodium falciparum pyrimethamine resistance multiple times in Africa
Single Nucleotide Polymorphism that Accompanies a Missense Mutation (Gln488His) Impedes the Dimerization of Hsp90.
A single nucleotide polymorphism (SNP) that causes a missense mutation of highly conserved Gln488 to His of the alpha isoform of the 90-kDa heat shock protein (Hsp90alpha) molecular chaperone is observed in Caucasians. The mutated Hsp90alpha severely reduced the growth of yeast cells. To investigate this molecular mechanism, we examined the domain-domain interactions of human Hsp90alpha by using bacterial 2-hybrid system. Hsp90alpha was expressed as a full-length form, N-terminal domain (residues 1-400), or middle (residues 401-617) plus C-terminal (residues 618-732) domains (MC domain/amino acids 401-732). The Gln488His substitution in MC domain did not affect the intra-molecular interaction with N-terminal domain, whereas the dimeric interaction-mediated by the inter-molecular interaction between MC domains was decreased to 32%. Gln488Ala caused a similar change, whereas Gln488Thr, which exceptionally occurs in mitochondrial Hsp90 paralog, fully maintained the dimeric interaction. Therefore, the SNP causing Gln488His mutation could abrogate the Hsp90 function due to reduced dimerization
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