Impact of Fluid Flow on Free Radical Polymerization in a Batch Reactor

In this work, the mixing process on a batch reactor is analyzed for the thermal synthesis of poly(acrylamide-co-sodium 2-acrylamide-2-methylpropane sulfonate) initiated by ammonium persulfate. The analysis is achieved by using tracer technology and computational fluid dynamics (CFD). ANSYS Fluent® software is used for numerical simulations. By studying the mixing time in the reactor, the injection point and the stirring speed are determined so that the kinetics of copolymerization is improved

Endoplasmic Reticulum Stress during Mammalian Follicular Atresia

Follicles are ovarian structures that contain a single germ cell. During the mammalian reproductive lifetime, ovarian follicles mature through the process of follicular development, with the aim of selecting oocytes for ovulation. As part of this process, several follicles are eliminated by means of follicular atresia, a mechanism that mainly involves apoptosis. Nevertheless, it has been shown that there are other routes of programmed cell death in the ovary including autophagy, paraptosis, and necroptosis. Surprisingly, the endoplasmic reticulum is involved in these different programmed cell death pathways. Moreover, there are several evidences for the pathways triggered by intra- and extracellular signals in endoplasmic reticulum-induced cell death. Thus, it is important to analyze the participation of endoplasmic reticulum in follicular atresia

Prevalence, risk factors, and identification of Salmonella spp. in stray dogs of northwest Mexico

Salmonellosis has a worldwide relevance in aspects associated with public health, as only in 2009 were reported 93.8 million cases in humans. The objective of the study was to establish the prevalence, risk factors and bacteriological and molecular identification of Salmonella spp in stray dogs in urban, rural and coastal areas of Mexicali, a city in northwest Mexico. From May 2014 to February 2015, 385 dogs were tested. Sampling was performed by rectal swab and conventional bacteriological techniques were applied, for later implementation of the API 20E system and molecular identification by polymerase chain reaction (PCR). The data were analysed statistically by means of descriptive statistics and multiple logistic regression modelling. A prevalence of 6.27% was obtained in the dogs examined, the samples obtained were characterised to subspecies (Salmonella enterica subspecies enterica and Salmonella enterica subspecie arizonae). The geographical region with the highest prevalence in the study was the coast (10%), followed by the rural area (8.57%) and the urban area (5.8%), however, no significant statistical differences were detected. There was significant difference in the prevalence by age of dogs under one year (P<0.05). The identification of Salmonella in dogs from northwest Mexico could correspond to serovars of zoonotic importance indicating a potential risk for the population

Fasciola hepatica and Rumen Flukes - In Vitro Evaluation of Main Commercial Anthelmintics

Background: Trematode infections are of great importance as they affect the health of many species of mammals as cattle, sheep and goat. Fasciola hepatica represents the main trematode zoonosis and risks to human and cattle and paramphistomosis is one emerging parasitic diseases of ruminants widely distributed in the world. The economic expenses are incurred by the use of ineffective anthelmintics for trematode control. Besides to faecal egg count reduction test (FECRT) to determine the anthelmintic efficacy, can be used in vitro assays, by this the aim of the study was to determine the lethal doses with hatching egg test of the main commercial anthelmintics used for the control of trematodes in cattle. Materials, Methods & Results: Liver and rumen were examined from cattle slaughtered in Tabasco, Chiapas and Campeche states from Mexico. F. hepatica eggs were recovered from gallbladder and rumen fluke eggs collected from adult parasites in saline solution. Subsequently, the hatching egg assays were performed placing 100 trematode eggs in distilled water in each one of 96 wells of polystyrene plates. After making the appropriate dilutions, several concentrations of commercial anthelmintics were evaluated, ranging from 0.04 to 80.63 mM for triclabendazole + 0.046 to 96.87 mM febendazole (TC+FBZ), from 0.04 to 91 mM for rafoxanide (RAFOX), from 0.02 to 43.74 mM for closantel (CLOS), from 0.036 to 76.18 mM for clorsulon + 0.002 to 3.31 mM ivermectin (CLORS+ IVM) and from 0.163 to 334.47 mM for nitroxynil (NITROX). A control group (water) was included in each plate. Lethal doses were obtained using the Probit procedure and analysis of the means with a one-way statistical design. Most drugs used against rumen fluke eggs presented a high LD50 and therefore were ineffective to cause egg mortality, such was the case of RAFOX that presented LD50 from 4,580 to 10,790 µg/mL (7 to 17 mM). CLOS presented the lowest LD50 (80 µg/mL or 0.12 mM) on rumen fluke eggs. TC+FBZ was found to be effective drug against the development of F. hepatica eggs in many samples. In the same way NITROX showed a low LD50 (37 to 63 µg/mL or 0.13 to 0.22 mM), but RAFOX presented a highest LD50 (1,450 µg/mL or 2.32 mM). Discussion: The present study focused on screen the ovicidal activity and determining in vitro lethal doses 50 of main commercial anthelmintics used to control F. hepatica and rumen fluke as rapid tests in a tropical region from Mexico. The FECRT is the main method to detect effectiveness of anthelmintic and other method is the coproantigen reduction test (CRT) by ELISA. Both tests require many infected animals depending the number of treatments and by this the egg hatch assay (EHA) represent a complementary diagnosis of effectiveness of anthelmintic products to compare between regions and even between farms, because few animals are required from the farm to collect trematode eggs, and it is possible to know the effectiveness against various anthelmintics at the same time. Efficacy studies on trematodes using egg hatching tests are scarce, although they have the advantage that they can be applied to both F. hepatica and rumen fluke. TC+FBZ was one of the most effective products in inhibiting the development of F. hepatica eggs. However, RAFOX showed low effectiveness against trematode eggs, with very high lethal doses. These results agree with a study that show low efficacy against the development of Paramphistomum cervi eggs and with the FECRT test reductions of 75% and 80.58% were obtained, in times from 7 to 84 days after treatment with RAFOX. NITROX and CLORS were drugs that had good efficacy on the development of F. hepatica eggs. A differential response between liver and rumen fluke was observed. The anthelmintics used against rumen fluke eggs show low ovicidal activity and in Fasciola hepatica TC+FBZ show the best activity. Keywords: trematodes, cattle, effectiveness, anthelmintics, ovicidal activity, egg hatching

Controlling the crystalline and magnetic texture in sputtered Fe 0.89 Ga 0.11 thin films: Influence of substrate and thermal treatment

In this work we present a careful study on the relationship between the magnetic and structural properties of a highly magnetostrictive Fe0.89Ga0.11 (Fe-Ga) alloy deposited onto glass, Si and MgO substrates. When grown on glass, the films are polycrystalline with randomly oriented grains without any texture, while the ones on Si and MgO present preferred growth directions. Fe-Ga/Si films show a [1 1 3] fibre-like texture, and Fe-Ga/MgO presents a quasi monocrystalline behavior with the (1 0 0) film plane direction parallel to the substrate surface. When Fe-Ga/MgO films are annealed an additional (1 1 0) texture is also observed. Magnetometry and ferromagnetic resonance (FMR) show that the magnetic behavior is closely related to the structural observed textures. Furthermore, the structural analysis allowed us to get a deeper understanding of the magnetic behavior. This point is very important to get the ability of controlling the crystalline texture by means of growing onto different substrates and/or thermal treatments, which in turns opens the possibility of handling the magnetic texture which is particularly important in magnetostrictive materials for electronic devices.Fil: Ramírez Chamorro, Gerardo Alexis. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Malamud, Florencia. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Gomez, Javier Enrique. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Rodríguez, Luis M.. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Fregenal, Daniel Eduardo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Butera, Alejandro Ricardo. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Milano, Julian. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; Argentin

Situación del mercado internacional de commodities agroalimentarios en los albores del siglo XXI

LIBRO: LA CRISIS ALIMENTARIA Y LA SALUD EN MÉXICO. EDITADO POR CASTELLANO EDITORES Y UNIVERSIDAD AUTÓNOMA DEL ESTADO DE MÉXICOEn el comienzo del presente siglo, el periodo de precios bajos en los mercados internacionales de commodities agroalimentarios se terminó, luego se entró a uno de fluctuaciones más frecuentes en dichos precios. El objetivo de la investigación es analizar la situación del mercado internacional de commodities agroalimentarias durante la primera década del siglo XXI, en específico el maíz, la soya y el trigo. Por ello se abordan el papel relevante del sector agroalimentario en una economía y una sociedad, además, los cambios que han existido en los agroalimentos durante el siglo XX. La metodología de apoyo es el estudio de la estructura de mercado de dichos productos agrícolas. Los resultados permiten entender la situación de concentración del mercado así como la situación de la oferta y la demanda internacionales. Se concluye que es un mercado en oligopolio y que existen factores de diversa índole que inciden en éste, desde lo demográfico hasta lo ambiental

Mutations related to Antiretroviral Resistance identified by ultra-deep sequencing in HIV-1 infected children under Structured Interruptions of HAART

Altres ajuts: CONACYT/GCPS/44519Although Structured Treatment Interruptions (STI) are currently not considered an alternative strategy for antiretroviral treatment, their true benefits and limitations have not been fully established. Some studies suggest the possibility of improving the quality of life of patients with this strategy; however, the information that has been obtained corresponds mostly to studies conducted in adults, with a lack of knowledge about its impact on children. Furthermore, mutations associated with antiretroviral resistance could be selected due to sub-therapeutic levels of HAART at each interruption period. Genotyping methods to determine the resistance profiles of the infecting viruses have become increasingly important for the management of patients under STI, thus low-abundance antiretroviral drug-resistant mutations (DRM's) at levels under limit of detection of conventional genotyping (<20% of quasispecies) could increase the risk of virologic failure. In this work, we analyzed the protease and reverse transcriptase regions of the pol gene by ultra-deep sequencing in pediatric patients under STI with the aim of determining the presence of high- and low-abundance DRM's in the viral rebounds generated by the STI. High-abundance mutations in protease and high- and low-abundance mutations in reverse transcriptase were detected but no one of these are directly associated with resistance to antiretroviral drugs. The results could suggest that the evaluated STI program is virologically safe, but strict and carefully planned studies, with greater numbers of patients and interruption/restart cycles, are still needed to evaluate the selection of DRM's during STI