10,046 research outputs found
Canister closing device Patent
Design and characteristics of device for closing canisters under high vacuum condition
Bounds on the derivatives of the Isgur-Wise function from sum rules in the heavy quark limit of QCD
Using the OPE and the trace formalism, we have obtained a number of sum rules
in the heavy quark limit of QCD that include the sum over all excited states
for any value of the light cloud. We show that these sum rules imply that
the elastic Isgur-Wise function is an alternate series in powers of
. Moreover, we obtain sum rules involving the derivatives of the elastic
Isgur-Wise function at zero recoil, that imply that the -th
derivative can be bounded by the -th one. For the curvature , this proves the already proposed bound . Moreover, we obtain the absolute bound for the -th derivative
, that generalizes the
results and .Comment: 9 pages, Late
Phenomenological Study of Strong Decays of Heavy Hadrons in Heavy Quark Effective Theory
The application of the tensor formalism of the heavy quark effective theory
(HQET) at leading order to strong decays of heavy hadrons is presented.
Comparisons between experimental and theoretical predictions of ratios of decay
rates for B mesons, D mesons and kaons are given. The application of HQET to
strange mesons presents some encouraging results. The spin-flavor symmetry is
used to predict some decay rates that have not yet been measured.Comment: 10 page
Chromosome mapping: radiation hybrid data and stochastic spin models
This work approaches human chromosome mapping by developing algorithms for
ordering markers associated with radiation hybrid data. Motivated by recent
work of Boehnke et al. [1], we formulate the ordering problem by developing
stochastic spin models to search for minimum-break marker configurations. As a
particular application, the methods developed are applied to 14 human
chromosome-21 markers tested by Cox et al. [2]. The methods generate
configurations consistent with the best found by others. Additionally, we find
that the set of low-lying configurations is described by a Markov-like ordering
probability distribution. The distribution displays cluster correlations
reflecting closely linked loci.Comment: 26 Pages, uuencoded LaTex, Submitted to Phys. Rev. E,
[email protected], [email protected]
Immune complex glomerulonephritis is induced in rats immunized with heterologous myeloperoxidase
Anti-neutrophil cytoplasmic antibodies (ANCA), including anti-myeloperoxidase (MPO) antibodies, are associated with pauci-immune necrotizing small vessel vasculitis or glomerulonephritis, 1n order to substantiate a pathogenic role for ANCA, an animal model of pauci-immune ANCA-induced glomerulonephritis or vasculitis is required. Brouwer reported pauci-immune glomerulonephritis in rats immunized with human MPO followed by perfusion of kidneys with lysosomal enzyme extract combined with HO, and suggested that this could serve as a model of ANCA-induced disease. We repeated these studies in spontaneously hypertensive rats (SHR) and Brown Norway rats (BNR). We immunized rats with human MPO, When circulating anti-MPO antibodies were detectable by indirect immunofluorescence microscopy and ELISA, blood pressure was measured, then perfusion of the left kidney of each rat was done via the renal artery in a closed, blood-free circuit with either MPO + HO, MPO, HO alone or MPO + HO neutral protease. Rats were killed on day 4 or day 10 after perfusion, and specimens were examined by light and immunofluorescence microscopy. Pathological lesions and deposits of IgG. C3, and MPO were found in immunized rats perfused with MPO + HO with or without neutral protease, or MPO alone, in both rat strains and on both day 4 and day 10, The degree of histologic injury was proportional in intensity to the amount of IgG immune deposits. Spontaneously hypertensive rats sustained more damage and higher blood pressure than Brown Norway rats. No lesion was observed in immunized rats perfused with HO or in the non-perfused right kidneys. Some of the non-immunized rats perfused with MPO + HO developed pathological lesions. In conclusion, these rat models are examples of immune complex-mediated glomerulonephritis, and therefore are not similar to human ANCA-associated disease
A relativistic chiral quark model for pseudoscalar emission from heavy mesons
The amplitudes for one-pion mediated transitions between heavy meson excited
states are obtained in the framework of the relativistic chiral quark model.
The effective coupling constants to pions and the decay widths of excited heavy
mesons with l<=2 for non-radially excited, and the l=0 radially excited mesons
are presented for both charmed and beauty mesons. We also discuss the allowed
decays of strange excited heavy mesons by emission of a K-meson.Comment: 20 pages, revte
More on Symmetries in Heavy Quark Effective Theory
We present a general classification of all normal and ``chiral" symmetries of
heavy quark effective theories. Some peculiarities and conondrums associated
with the ``chiral" symmetries are discussed.Comment: 15 pages, preprint UR-1320, ER40685-77
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