3,420 research outputs found
Phase transitions in a gas of anyons
We continue our numerical Monte Carlo simulation of a gas of closed loops on
a 3 dimensional lattice, however now in the presence of a topological term
added to the action corresponding to the total linking number between the
loops. We compute the linking number using certain notions from knot theory.
Adding the topological term converts the particles into anyons. Using the
correspondence that the model is an effective theory that describes the
2+1-dimensional Abelian Higgs model in the asymptotic strong coupling regime,
the topological linking number simply corresponds to the addition to the action
of the Chern-Simons term. We find the following new results. The system
continues to exhibit a phase transition as a function of the anyon mass as it
becomes small \cite{mnp}, although the phases do not change the manifestation
of the symmetry. The Chern-Simons term has no effect on the Wilson loop, but it
does affect the {\rm '}t Hooft loop. For a given configuration it adds the
linking number of the 't Hooft loop with all of the dynamical vortex loops to
the action. We find that both the Wilson loop and the 't Hooft loop exhibit a
perimeter law even though there are no massless particles in the theory, which
is unexpected.Comment: 6 pages, 5 figure
Monolithic large-signal transimpedance amplifier for use in multi-gigabit, short-range optoelectronic interconnect applications
Published versio
Properties Study of ZnS Thin Films Prepared by Spray Pyrolysis Method
Zinc sulfide (ZnS) is important II-VI semiconductors material for the development of various modern
technologies and photovoltaic applications. ZnS thin film was prepared by using chemical spray pyrolysis
technique. The starting solution is a mixture of 0.1 M zinc chloride as source of Zn and 0.05 M thiourea as
source of S. The glass substrate temperature was varied in the range of 300 °C-400 °C to investigate the influence of substrate temperature on the structure, chemical composition, morphological and optical properties of ZnS films. The DRX analyses indicated that ZnS films have polycrystalline cubic structure with
(111) preferential orientation and grain size varied from 25 to 60 nm, increasing with substrate temperature.
The optical properties of these films have been studied in the wavelength range 300-2500 nm using
UV-VIS spectro-photometer. The ZnS films has a band gap of 3.89 eV-3.96 eV
Properties Study of ZnS Thin Films Prepared by Spray Pyrolysis Method
Zinc sulfide (ZnS) is important II-VI semiconductors material for the development of various modern
technologies and photovoltaic applications. ZnS thin film was prepared by using chemical spray pyrolysis
technique. The starting solution is a mixture of 0.1 M zinc chloride as source of Zn and 0.05 M thiourea as
source of S. The glass substrate temperature was varied in the range of 300 °C-400 °C to investigate the influence of substrate temperature on the structure, chemical composition, morphological and optical properties of ZnS films. The DRX analyses indicated that ZnS films have polycrystalline cubic structure with
(111) preferential orientation and grain size varied from 25 to 60 nm, increasing with substrate temperature.
The optical properties of these films have been studied in the wavelength range 300-2500 nm using
UV-VIS spectro-photometer. The ZnS films has a band gap of 3.89 eV-3.96 eV
Unilateral ganglionectomy technique on the sheep's cranial cervical ganglion as a support for morphofunctional and quantitative studies
The article has no abstract
Galactic Bulge Microlensing Optical Depth from EROS-2
We present a new EROS-2 measurement of the microlensing optical depth toward
the Galactic Bulge. Light curves of clump-giant stars
distributed over of the Bulge were monitored during seven Bulge
seasons. 120 events were found with apparent amplifications greater than 1.6
and Einstein radius crossing times in the range 5 {\rm d}.
This is the largest existing sample of clump-giant events and the first to
include northern Galactic fields. In the Galactic latitude range
1.4\degr<|b|<7.0\degr, we find with . These results are in good
agreement with our previous measurement, with recent measurements of the MACHO
and OGLE-II groups, and with predictions of Bulge models.Comment: accepted A&A, minor revision
Removing the Microlensing Blending-Parallax Degeneracy Using Source Variability
Microlensing event MACHO 97-SMC-1 is one of the rare microlensing events for
which the source is a variable star, simply because most variable stars are
systematically eliminated from microlensing studies. Using observational data
for this event, we show that the intrinsic variability of a microlensed star is
a powerful tool to constrain the nature of the lens by breaking the degeneracy
between the microlens parallax and the blended light. We also present a
statistical test for discriminating the location of the lens based on the
\chi^2 contours of the vector \Lambda, the inverse of the projected velocity.
We find that while SMC self lensing is somewhat favored over halo lensing,
neither location can be ruled out with good confidence.Comment: 15 text pages + 2 tables + 7 figures. Published in the Astrophysical
Journa
A novel substitution in NS5A enhances the resistance of hepatitis C virus genotype 3 to daclatasvir
Hepatitis C virus (HCV) genotype 3 presents a high level of both baseline and acquired resistance to direct-acting antivirals (DAAs), particularly those targeting the NS5A protein. To understand this resistance we studied a cohort of Brazilian patients treated with the NS5A DAA, daclatasvir and the nucleoside analogue, sofosbuvir. We observed a novel substitution at NS5A amino acid residue 98 [serine to glycine (S98G)] in patients who relapsed post-treatment. The effect of this substitution on both replication fitness and resistance to DAAs was evaluated using two genotype 3 subgenomic replicons. S98G had a modest effect on replication, but in combination with the previously characterized resistance-associated substitution (RAS), Y93H, resulted in a significant increase in daclatasvir resistance. This result suggests that combinations of substitutions may drive a high level of DAA resistance and provide some clues to the mechanism of action of the NS5A-targeting DAAs
Resveratrol has antiinflammatory and antifibrotic effects in the peptidoglycan‐polysaccharide rat model of Crohn's disease
Background: Resveratrol has antiinflammatory and antifibrotic effects. Resveratrol decreases proliferation and collagen synthesis by intestinal smooth muscle cells. We hypothesized that resveratrol would decrease inflammation and fibrosis in an animal model of Crohn's disease. Methods: Peptidoglycan‐polysaccharide (PG‐PS) or human serum albumin (HSA) was injected into the bowel wall of Lewis rats at laparotomy. Resveratrol or vehicle was administered daily by gavage 1–27 days postinjection. On day 28, gross abdominal and histologic findings were scored. Cecal collagen content was measured by colorimetric analysis of digital images of trichrome‐stained sections. Cecal levels of procollagen, cytokine, and growth factor mRNAs were determined. Results: PG‐PS‐injected rats (vehicle‐treated) developed more fibrosis than HSA‐injected rats by all measurements: gross abdominal score ( P < 0.001), cecal collagen content ( P = 0.04), and procollagen I and III mRNAs ( P ≤ 0.0007). PG‐PS‐injected rats treated with 40 mg/kg resveratrol showed a trend toward decreased gross abdominal score, inflammatory cytokine mRNAs, and procollagen mRNAs. PG‐PS‐injected rats treated with 100 mg/kg resveratrol had lower inflammatory cytokine mRNAs (IL‐1β [3.50 ± 1.08 vs. 10.79 ± 1.88, P = 0.005], IL‐6 [17.11 ± 9.22 vs. 45.64 ± 8.83, P = 0.03], tumor necrosis factor alpha (TNF‐α) [0.80 ± 0.14 vs. 1.89 ± 0.22, P = 0.002]), transforming growth factor beta 1 (TGF‐β1) mRNA (2.24 ± 0.37 vs. 4.06 ± 0.58, P = 0.01), and histologic fibrosis score (6.4 ± 1.1 vs. 9.8 ± 1.0; P = 0.035) than those treated with vehicle. There were trends toward decreased gross abdominal score and decreased cecal collagen content. Procollagen I, procollagen III, and IGF‐I mRNAs also trended downward. Conclusions: Resveratrol decreases inflammatory cytokines and TGF‐β1 in the PG‐PS model of Crohn's disease and demonstrates a promising trend in decreasing tissue fibrosis. These findings may have therapeutic applications in inflammatory bowel disease. (Inflamm Bowel Dis 2011;)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90530/1/21843_ftp.pd
Estudo comparativo entre flunizina meglumina ou buprenorfina no procedimento de ovariohisterectomia em gatas
O artigo não apresenta resumo
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