Decoherence from internal degrees of freedom for cluster of mesoparticles : a hierarchy of master equations

A mesoscopic evolution equation for an ensemble of mesoparticles follows after the elimination of internal degrees of freedom. If the system is composed of a hierarchy of scales, the reduction procedure could be worked repeatedly and the characterization of this iterating method is carried out. Namely, a prescription describing a discrete hierarchy of master equations for the density operator is obtained. Decoherence follows from the irreversible coupling of the systems, defined by mesoscopic variables, to internal degrees of freedom. We discuss briefly the existence of systems with the same dynamics laws at different scales. We made an explicit calculation for an ensemble of particles with internal harmonic interaction in an external anharmonic field. New conditions related to the semiclassical limit for mesoscopic systems (Wigner-function) are conjectured.Comment: 19 pages, 0 figures, late

Chemical composition, physicochemical evaluation and sensory analysis of yogurt added with extract of polyphenolic compounds from Quercus crassifolia oak bark

Introduction: A diet high in calories and saturated fats has been associated with health problems that have been increasing worldwide. Therefore, it is required to increase the number of formulated foods that generate well-being to health. Yogurt is a widely consumed food by all sectors of the population and it can be used as a vehicle to incorporate bioactive compounds. The phenolic compounds present in forest residues, such as those from oak bark, can be used and incorporated into yogurt, to increase its benefits as a functional food. Objective: The objective of this study was to develop a multifunctional yogurt enriched with vegetable oil (2.3% w/w) as a source of omega 6 and 3 and adding nanocapsules (24.5% w/w) of an extract of oak bark from Quercus crassifolia, rich in in phenolic compounds and high antioxidant capacity. Methods: Three yogurt formulations were prepared: F1: yogurt was made with non-fat milk, used as a control, F2: yogurt was prepared with non-fat milk and added with vegetable palm oil, and F3: non-fat yogurt was added with vegetable oil and nanoencapsulated oak bark phenolic extract. The yogurts were characterized in their chemical composition, microbiological analysis, and sensory analysis. Results: The multifunctional product F3 and product F2 presented lactic acid bacteria in concentration of 3.01X106 and 4.73x106, respectively, preserving characteristics of probiotic food. Product F3 presented low levels of syneresis (7.34%) and it was significantly different from the control yogurt (9.01%). The viscosity increased from 150 cP in the control yogurt to 341 cP in F3, due to the increase in the concentrations of solids by nanoencapsulating the phenolic. The wall material used for nanoencapsulation was sodium caseinate and mantodextrin. However, this increase in viscosity did not affect the sensory evaluation of the product. There were no significant differences between the control yogurt and the F2 and F3 products. Conclusion: A yogurt added with vegetable oil and nanoencapsulated oak bark phenolic extract was obtained. It was enhanced by the presence of probiotics, bioactive compounds, and essential fatty acids, and then evaluated and accepted by a sensory panel. Nanoencapsulation is a viable alternative to mask the characteristic astringent taste of phenolic compounds because it was not detected by the panelists

Assessment of the toll-like receptor 4 Asp299Gly, Thr399Ile and interleukin-8 -251 polymorphisms in the risk for the development of distal gastric cancer

<p>Abstract</p> <p>Background</p> <p>The intensity of the inflammation induced by <it>Helicobacter pylori </it>colonization is associated with the development of distal gastric cancer (GC). The host response to <it>H</it>. <it>pylori </it>has been related to genetic polymorphisms that influence both innate and adaptive immune responses.</p> <p>Our aim was to investigate whether the presence of the <it>TLR4 Asp299Gly</it>, <it>TLR4 Thr399Ile </it>and <it>IL-8-251 </it>A/T polymorphisms had any influence in the development of distal GC in a Mexican population.</p> <p>Methods</p> <p>We studied 337 patients that were divided in two groups: 78 patients with histologically confirmed distal GC and 259 non-cancer controls. The presence of <it>H. pylori </it>in the control population was defined by positive results of at least two of four diagnostic tests: serology, histology, rapid urease test and culture. Human DNA was purified and genotyped for <it>TLR4 Asp299Gly </it>polymorphism by pyrosequencing, for <it>TLR4 Thr399Ile </it>by PCR-RFLP and for <it>IL8-251 </it>by the amplification refractory mutation system (ARMS)-PCR.</p> <p>Results</p> <p>The non-cancer control group was found to be in Hardy-Weinberg equilibrium at the polymorphic loci studied (chi-square _H-W= 0.58 for <it>IL8-251</it>, 0.42 for <it>TLR4 Asp299Gly </it>and 0.17 for <it>TLR4 Thr399Ile</it>). The frequencies of mutated alleles (homozygous plus heterozygous) were compared between cases and controls. We found no significant difference for <it>TLR4- Asp299Gly </it>[the 7.7% of distal GC patients and 7.7 % non-cancer controls (p = 0.82)] and for <it>TLR4 Thr399Ile </it>[the 1.3% of GC patients and the 5% of the control population (p = 0.2)]. In contrast, for <it>IL-8-251 </it>A/T, 80.77% of the GC patients and 66.4% in the control group age and gender matched had at least one copy of mutated allele (OR = 2.12, 95% CI = 1.1–4.2) (p = 0.023).</p> <p>Conclusion</p> <p>This study showed that the <it>IL8-251*A </it>allele could be related to the development of distal gastric cancer in this Mexican population.</p

Photo-detection using Bose-condensed atoms in a micro trap

A model of photo-detection using a Bose--Einstein condensate in an atom-chip based micro trap is analyzed. Atoms absorb photons from the incident light field, receive part of the photon momentum and leave the trap potential. Upon counting of escaped atoms within predetermined time intervals, the photon statistics of the incident light is mapped onto the atom-count statistics. Whereas traditional photo-detection theory treats the emission centers of photo electrons as distinguishable, here the centers of escaping atoms are condensed and thus indistinguishable atoms. From this an enhancement of the photon-number resolution as compared to the commonly known counting formula is derived.Comment: 11 pages, 5 figures; revised versio

Terrestrial snail communities of the lower rio grande valley are affected by human disturbance and correlate with vegetation community composition

The lower Rio Grande Valley of Texas (LRGV) contains a unique, subtropical, semiarid floodplain with most of the few remaining Tamaulipan thorn forests in the United States. Less than 2% of Tamaulipan thorn forest remains, with urban and agricultural conversion potentially threatening diverse plant and animal communities native to the habitat. We performed vegetative community surveys and conducted a comprehensive survey of terrestrial snail communities in intact (refugia sites, minimally altered in recent times) and altered (previously cleared and regrown or restored) Tamaulipan thorn forest habitats of the LRGV. In a comparison of intact and altered sites that have comparable vegetation (paired sites), we found that intact sites had a less species-rich snail community than their altered counterparts, but this difference was not statistically significant. This counterintuitive result, in part reflects the fact that the most species-rich, intact snail communities (i.e., Sabal Palm Forest) have no altered (restored or regrown) counterparts and so were not included in the paired comparisons. A nestedness analysis supports this, finding that these unique intact sites, which have the highest species richness and no comparable restored sites, contain the largest pool of species in South Texas. Species richness of snails significantly correlated with a precipitation gradient. A general linear model incorporating mean canopy cover, mean plant height, plant abundance, and plant species richness shows a significant correlation with snail communities. This study is the only comprehensive survey of the snail communities of the lower Rio Grande Valley. - La cuenca baja del río Grande en Texas (LRGV) contiene una llanura de inundación única, subtropical y semiárida con la mayor´ıa de los remanentes de los bosques espinosos tamaulipecos en los Estados Unidos. Queda menos del 2% del bosque espinoso tamaulipeco, con la conversión a áreas urbanas y agrıcolas potencialmente amenazando las comunidades diversas de plantas y animales nativos del hábitat. Hicimos muestreos de comunidades vegetales y un muestreo comprensivo de comunidades de caracoles terrestres en hábitats de bosques espinosos tamaulipecos intactos (sitios refugio, con poca alteración en tiempos recientes) y perturbados (previamente cortados y recuperados o restaurados) en el LRGV. En una comparaci ´on de los sitios intactos con los perturbados con la vegetación comparable (sitios emparejados), sitios intactos tuvieron comunidades con menos riqueza de especies de caracoles que sus contrapartes alteradas, aunque la diferencia no fue estad´ısticamente significativa. Este resultado contra intuitivo, en parte refleja el hecho de que las comunidades intactas de caracoles mas ricas en especies (o sea, Sabal Palm Forest) no tienen contrapartes alteradas (restauradas o regeneradas) y por eso no fueron incluidas en las comparaciones emparejadas. Un análisis de anidamiento respalda esto, encontrando que estos ´unicos sitios intactos, que tienen la mayor riqueza de especies y ningun sitio comparable restaurado, contienen el grupo más grande de especies en el sur de Texas. La riqueza de especies de caracoles se correlacion significativamente con un gradiente de precipitación. Un modelo lineal general incorporando el promedio de cobertura del dosel, el promedio de altura vegetal, la abundancia de plantas, y la riqueza de especies de plantas muestra una correlación significativa con comunidades de caracoles. Este es el único muestreo comprensivo de las comunidades de caracoles de la cuenca baja del río Grande

Intrinsic decoherence and classical-quantum correspondence in two coupled delta-kicked rotors

We show that classical-quantum correspondence of center of mass motion in two coupled delta-kicked rotors can be obtained from intrinsic decoherence of the system itself which occurs due to the entanglement of the center of mass motion to the internal degree of freedom without coupling to external environment

The Large Aperture GRB Observatory

The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in arrays of Water Cherenkov Detectors (WCD) in high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). WCD at high altitude offer a unique possibility of detecting low gamma fluxes in the 10 GeV - 1 TeV range. The status of the Observatory and data collected from 2007 to date will be presented.Comment: 4 pages, proceeding of 31st ICRC 200

Water Cherenkov Detectors response to a Gamma Ray Burst in the Large Aperture GRB Observatory

In order to characterise the behaviour of Water Cherenkov Detectors (WCD) under a sudden increase of 1 GeV - 1 TeV background photons from a Gamma Ray Burst (GRB), simulations were conducted and compared to data acquired by the WCD of the Large Aperture GRB Observatory (LAGO). The LAGO operates arrays of WCD at high altitude to detect GRBs using the single particle technique. The LAGO sensitivity to GRBs is derived from the reported simulations of the gamma initiated particle showers in the atmosphere and the WCD response to secondaries.Comment: 5 pages, proceeding of the 31st ICRC 200

STUDY ON NUTRITIONAL AND ELEMENTAL ANALYSIS OF THE SEAWEEDS OF NORTHERN SAMAR, PHILIPINES

The purpose of the study: In this work, the nutritional and elemental analysis of seaweeds in Northern Samar is analyzed. Methodology: The seaweeds of Northern Samar are collected from the intertidal zone, and it was brought back to the College of Science for taxonomic identity.&nbsp;&nbsp; The nutritional and elemental content of the seaweeds were determined. Main findings: Based on the results obtained a total of 39 species belonging to eighteen (18) families of seaweeds were recorded from different coastal towns in Northern Samar, Philippines.&nbsp; The results revealed that for seaweeds with the economic value the nutritional and elemental content is comparable to the unknown seaweeds with no economic value.&nbsp;&nbsp;&nbsp;&nbsp; Implications: The results of the bioavailability of nutrients of this study might be the basis that unknown seaweeds with no economic value can be used directly in the diet and promote health advantage. Originality/Novelty of study: The seaweeds of Northern Samar are not properly documented in comparison with other marine flora.&nbsp; The results demonstrated that some species of seaweeds collected in Northern Samar with no economic value could also accumulate non-essential elements.&nbsp; Further studies would surely be a great contribution to our local food and pharmaceutical industries.&nbsp