11,568 research outputs found
Cluster Algorithm for a Solid-On-Solid Model with Constraints
We adapt the VMR (valleys-to-mountains reflections) algorithm, originally
devised by us for simulations of SOS models, to the BCSOS model. It is the
first time that a cluster algorithm is used for a model with constraints. The
performance of this new algorithm is studied in detail in both phases of the
model, including a finite size scaling analysis of the autocorrelations.Comment: 10 pages, 3 figures appended as ps-file
Better dairying competition
The success of the Better Dairying Competition in previous years prompted the Western Australian Pasture Improvement Committee of the Australian Dairy Produce Board to again sponsor a similar competition during 1952-1953. The committee which receives funds from the the Australian Dairy Produce Board and Rural Credits Branch of the Commonwealth Bank, offered substantial cash prizes to the six zones as detailed below
Receptor tyrosine kinase and p16/CDKN2 expression in a case of tripe palms associated with non-small-cell lung cancer
Background: Tripe palms is a descriptive term for a cutaneous paraneoplastic keratoderma. Tripe palms are frequently associated with gastric and pulmonary carcinoma. The pathogenetic mechanism remains unknown. Objective: To determine the influence of receptor tyrosine kinases, which are both expressed in pulmonary carcinomas and in human skin, we performed expression studies on epidermal growth factor receptor (EGFR), HER2, HERS in a skin sample of tripe palms obtained from a patient with non-small-cell lung cancer with lymph node involvement. Two months after diagnosis, the patient had developed palmoplantar `tripe palms'. Additionally, the expression of SRC, c-myc and p16/CDKN2 were studied. Method: Conventional reverse-transcription polymerase chain reaction was performed on a tissue sample of tripe palms. Results: Weak expression of HER2 and of p16/CDKN2 was found. EGFR, HERS, c-myc and SRC were not expressed. Conclusion: Receptor tyrosine kinases of subclass I, the tyrosine kinase SRC and the oncogene c-myc play no major role in the pathogenesis of this case of tripe palms. Copyright (C) 2000 S. Karger AG. Basel
Critical exponents of a three dimensional O(4) spin model
By Monte Carlo simulation we study the critical exponents governing the
transition of the three-dimensional classical O(4) Heisenberg model, which is
considered to be in the same universality class as the finite-temperature QCD
with massless two flavors. We use the single cluster algorithm and the
histogram reweighting technique to obtain observables at the critical
temperature. After estimating an accurate value of the inverse critical
temperature \Kc=0.9360(1), we make non-perturbative estimates for various
critical exponents by finite-size scaling analysis. They are in excellent
agreement with those obtained with the expansion method with
errors reduced to about halves of them.Comment: 25 pages with 8 PS figures, LaTeX, UTHEP-28
In Vitro Complement-Binding on Cytoplasmic Structures in Normal Human Skin: I. Immunofluorescence Studies
Incubation of cryostat sections of normal human skin with normal human serum (NHS) at 37°C followed by fluorescein isothiocyanate labeled rabbit antihuman C3 (FITC-R/Hu-C3) yields cytoplasmic staining of various cell types including keratinocytes of the upper epidermal layers, melanocytes, fibroblasts, smooth muscle cells, and cells lining vascular structures.Deposition of C3 on the respective cytoplasmic structures is most likely due to activation of the classical complement (C) cascade on these structures since no fluorescent staining is observed when serum of patients with hereditary C4-deficiency is used instead of NHS or when incubation with NHS is performed in the presence of EDTA or EGTA in concentrations known to inhibit classical C pathway activation. Further evidence suggesting the involvement of the classical C pathway comes from the finding that incubation of cryostat skin sections with NHS followed by FITC labeled rabbit antihuman Clq (FITC-R/Hu-Clq) results in a fluorescent staining pattern remarkably similar to that seen after exposure of cryostat skin sections to NHS and FITC-R/ Hu-C3.Although formal proof is lacking, our investigations strongly indicate that binding to and activation of C components on cytoplasmic structures occur independently of the presence of circulating antibodies. This assumption is based on the finding that in 17 out of 20 NHS we were not able to detect any skin reactive antibodies by indirect immunofluorescence (IF) techniques. More conclusive evidence for a direct, antibody-independent interaction between C components and cytoplasmic structures is provided by the observation that incubation of the substrate with purified Clq followed by FITC-R/ Hu-Clq results in cytoplasmic staining of some of the skin cell populations described above.The phenomenon of C-binding adn activation on cytoplasmic structures of normal human skin cells may be a critical event in the initiation of complement mediated pathopysiological reactions of the skin
Theoretical Analysis of Acceptance Rates in Multigrid Monte Carlo
We analyze the kinematics of multigrid Monte Carlo algorithms by
investigating acceptance rates for nonlocal Metropolis updates. With the help
of a simple criterion we can decide whether or not a multigrid algorithm will
have a chance to overcome critial slowing down for a given model. Our method is
introduced in the context of spin models. A multigrid Monte Carlo procedure for
nonabelian lattice gauge theory is described, and its kinematics is analyzed in
detail.Comment: 7 pages, no figures, (talk at LATTICE 92 in Amsterdam
Site-diluted three dimensional Ising Model with long-range correlated disorder
We study two different versions of the site-diluted Ising model in three
dimensions with long-range spatially correlated disorder by Monte Carlo means.
We use finite-size scaling techniques to compute the critical exponents of
these systems, taking into account the strong scaling-corrections. We find a
value that is compatible with the analytical predictions.Comment: 19 pages, 1 postscript figur
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