437 research outputs found
Coexistent duodenal ulcer among patients with gastric carcinoma
To examine the prevalence of coexistent duodenal ulcers among patients with gastric carcinoma in an otherwise intact stomach, we surveyed 604 endoscopically and pathologically diagnosed gastric carcinoma patients and thoroughly inspected their duodenums. Twenty-two (3,6%) of them had either active ulcers or scars in the duodenum. This prevalence was significantly less than that among 99 (16,4%) of 604 age- and gender-matched control with endoscopically confirmed duodenal ulcers (P < 0,0001). Almost one-half of patients with coexistent cancer and duodenal ulcer experienced no change in abdominal symptoms when gastric cancer was diagnosed. Barium meal study appeared not to be sensitive enough to diagnose the coexistent ulcers. However, the nature of the lesions, including disease location, macroscopic appearance, chance of early cancer and metastasis, was no different in 22 patients with coexistent cancer and duodenal ulcer than in 582 patients with cancer alone. The present study suggests that although duodenal ulcer is unlikely to be a predisposing factor for gastric cancer, thorough screening by means of endoscopy is necessary in dyspepsic ulcer patients since duodenal ulcer and gastric cancer are not incompatible
Zeroes of the Jones polynomial
We study the distribution of zeroes of the Jones polynomial for a
knot . We have computed numerically the roots of the Jones polynomial for
all prime knots with crossings, and found the zeroes scattered about
the unit circle with the average distance to the circle approaching a
nonzero value as increases.
For torus knots of the type we show that all zeroes lie on the unit
circle with a uniform density in the limit of either or , a
fact confirmed by our numerical findings. We have also elucidated the relation
connecting the Jones polynomial with the Potts model, and used this relation to
derive the Jones polynomial for a repeating chain knot with crossings for
general . It is found that zeroes of its Jones polynomial lie on three
closed curves centered about the points and . In addition, there are
two isolated zeroes located one each near the points
at a distance of the order of . Closed-form expressions are
deduced for the closed curves in the limit of .Comment: 12 pages, 5 figure
Scaling laws for the 2d 8-state Potts model with Fixed Boundary Conditions
We study the effects of frozen boundaries in a Monte Carlo simulation near a
first order phase transition. Recent theoretical analysis of the dynamics of
first order phase transitions has enabled to state the scaling laws governing
the critical regime of the transition. We check these new scaling laws
performing a Monte Carlo simulation of the 2d, 8-state spin Potts model. In
particular, our results support a pseudo-critical beta finite-size scaling of
the form beta(infinity) + a/L + b/L^2, instead of beta(infinity) + c/L^d +
d/L^{2d}. Moreover, our value for the latent heat is 0.294(11), which does not
coincide with the latent heat analytically derived for the same model if
periodic boundary conditions are assumed, which is 0.486358...Comment: 10 pages, 3 postscript figure
Simulation of Potts models with real q and no critical slowing down
A Monte Carlo algorithm is proposed to simulate ferromagnetic q-state Potts
model for any real q>0. A single update is a random sequence of disordering and
deterministic moves, one for each link of the lattice. A disordering move
attributes a random value to the link, regardless of the state of the system,
while in a deterministic move this value is a state function. The relative
frequency of these moves depends on the two parameters q and beta. The
algorithm is not affected by critical slowing down and the dynamical critical
exponent z is exactly vanishing. We simulate in this way a 3D Potts model in
the range 2<q<3 for estimating the critical value q_c where the thermal
transition changes from second-order to first-order, and find q_c=2.620(5).Comment: 5 pages, 3 figures slightly extended version, to appear in Phys. Rev.
Magnetic-Field Induced First-Order Transition in the Frustrated XY Model on a Stacked Triangular Lattice
The results of extensive Monte Carlo simulations of magnetic-field induced
transitions in the xy model on a stacked triangular lattice with
antiferromagnetic intraplane and ferromagnetic interplane interactions are
discussed. A low-field transition from the paramagnetic to a 3-state (Potts)
phase is found to be very weakly first order with behavior suggesting
tricriticality at zero field. In addition to clarifying some long-standing
ambiguity concerning the nature of this Potts-like transition, the present work
also serves to further our understanding of the critical behavior at ,
about which there has been much controversy.Comment: 10 pages (RevTex 3.0), 4 figures available upon request, CRPS-93-0
Potts model on recursive lattices: some new exact results
We compute the partition function of the Potts model with arbitrary values of
and temperature on some strip lattices. We consider strips of width
, for three different lattices: square, diced and `shortest-path' (to be
defined in the text). We also get the exact solution for strips of the Kagome
lattice for widths . As further examples we consider two lattices
with different type of regular symmetry: a strip with alternating layers of
width and , and a strip with variable width. Finally we make
some remarks on the Fisher zeros for the Kagome lattice and their large
q-limit.Comment: 17 pages, 19 figures. v2 typos corrected, title changed and
references, acknowledgements and two further original examples added. v3 one
further example added. v4 final versio
Spin-Peierls phases in pyrochlore antiferromagnets
In the highly frustrated pyrochlore magnet spins form a lattice of corner
sharing tetrahedra. We show that the tetrahedral ``molecule'' at the heart of
this structure undergoes a Jahn-Teller distortion when lattice motion is
coupled to the antiferromagnetism. We extend this analysis to the full
pyrochlore lattice by means of Landau theory and argue that it should exhibit
spin-Peierls phases with bond order but no spin order. We find a range of Neel
phases, with collinear, coplanar and noncoplanar order. While collinear Neel
phases are easiest to generate microscopically, we also exhibit an interaction
that gives rise to a coplanar state instead.Comment: REVTeX 4, 14 pages, 12 figures (best viewed in color
Integrating internationalization in the user-centered software development process
The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-39143-9_27Proceedings of 5th International Conference, CCD 2013, Held as Part of HCI International 2013, Las Vegas, NV, USA, July 21-26, 2013Internationalization is a common practice today in software development. In the most basic sense, internationalization is carried out by applying localization design guidelines to face language translation, icon representation, character sets and so on. However, this practice is mostly intended for design purposes, which results insufficient when applying internationalization in huge projects and, specifically, through a concrete development process. In this paper, a broader framework is provided in order to ensure internationalization through a software development process. To this end, a set of activities and sub-activities will be presented involving not only design but pre-development, analysis, implementation and evaluation issues that need to be considered for a right internationalization assurance in international software development. The idea behind is to bridge the gap between simple and usual localization activities and the user-centered software development process as internationalization assurance also helps increase the quality and usability of the software overall.This work has been supported by the founded projects TIN2011-24139, S2009/TIC-1650 and TIN2011-15009-
Quasicondensate and superfluid fraction in the 2D charged-boson gas at finite temperature
The Bogoliubov - de Gennes equations are solved for the Coulomb Bose gas
describing a fluid of charged bosons at finite temperature. The approach is
applicable in the weak coupling regime and the extent of its quantitative
usefulness is tested in the three-dimensional fluid, for which diffusion Monte
Carlo data are available on the condensate fraction at zero temperature. The
one-body density matrix is then evaluated by the same approach for the
two-dimensional fluid with e^2/r interactions, to demonstrate the presence of a
quasi-condensate from its power-law decay with increasing distance and to
evaluate the superfluid fraction as a function of temperature at weak coupling.Comment: 9 pages, 2 figure
Multiplex Amplification Refractory Mutation System Polymerase Chain Reaction (ARMS-PCR) for diagnosis of natural infection with canine distemper virus
<p>Abstract</p> <p>Background</p> <p>Canine distemper virus (CDV) is present worldwide and produces a lethal systemic infection of wild and domestic <it>Canidae</it>. Pre-existing antibodies acquired from vaccination or previous CDV infection might interfere the interpretation of a serologic diagnosis method. In addition, due to the high similarity of nucleic acid sequences between wild-type CDV and the new vaccine strain, current PCR derived methods cannot be applied for the definite confirmation of CD infection. Hence, it is worthy of developing a simple and rapid nucleotide-based assay for differentiation of wild-type CDV which is a cause of disease from attenuated CDVs after vaccination. High frequency variations have been found in the region spanning from the 3'-untranslated region (UTR) of the matrix (M) gene to the fusion (F) gene (designated M-F UTR) in a few CDV strains. To establish a differential diagnosis assay, an amplification refractory mutation analysis was established based on the highly variable region on M-F UTR and F regions.</p> <p>Results</p> <p>Sequences of frequent polymorphisms were found scattered throughout the M-F UTR region; the identity of nucleic acid between local strains and vaccine strains ranged from 82.5% to 93.8%. A track of AAA residue located 35 nucleotides downstream from F gene start codon highly conserved in three vaccine strains were replaced with TGC in the local strains; that severed as target sequences for deign of discrimination primers. The method established in the present study successfully differentiated seven Taiwanese CDV field isolates, all belonging to the Asia-1 lineage, from vaccine strains.</p> <p>Conclusions</p> <p>The method described herein would be useful for several clinical applications, such as confirmation of nature CDV infection, evaluation of vaccination status and verification of the circulating viral genotypes.</p
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