El mercado de Ecuador como una oportunidad de negocios para la exportación de tubos pvc por parte de la empresa Eurotubo, periodo 2017 – 2021

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Structural properties of fluids interacting via piece-wise constant potentials with a hard core

Publicado en: J. Chem. Phys. 139, 074505 (2013) DOI: 10.1063/1.4818601Se presentan las propiedades estructurales de fluidos cuyas moléculas interactúan a través de potenciales con un núcleo duro más dos secciones constantes de diferentes anchuras y alturas. Éstos se derivan de un desarrollo más general presentado previamente para potenciales con un núcleo duro además de ƞ constante [Condens. Matter Phys. 15, 23602 (2012)] en el que se hizo uso de un método analítico de aproximación racional-función y semi-analítico. Los resultados de casos ilustrativos que comprenden ocho diferentes combinaciones de pozos y barreras son comparadas con datos de simulación y con aquellos que se derivan de la solución numérica de las ecuaciones integrales de Percus–Yevick y cadenas superentrelazadas. Se encuentra que la aproximación racional-funcional generalmente predice una función de distribución radial más precisa que la teoría de Percus–Yevick y es comparable o incluso superior a la teoría de cadenas superentrelazadas. Esta superioridad sobre ambas teorías de la ecuación integral se pierde, sin embargo, en altas densidades, especialmente cuando aumenta la amplitud de los pozos y/o barreras.The structural properties of fluids whose molecules interact via potentials with a hard core plus two piece-wise constant sections of different widths and heights are presented. These follow from the more general development previously introduced for potentials with a hard core plus n piece-wise constant sections [Condens. Matter Phys. 15, 23602 (2012)] in which use was made of a semi-analytic rational-function approximation method. The results of illustrative cases comprising eight different combinations of wells and shoulders are compared both with simulation data and with those that follow from the numerical solution of the Percus–Yevick and hypernetted-chain integral equations. It is found that the rational-function approximation generally predicts a more accurate radial distribution function than the Percus–Yevick theory and is comparable or even superior to the hypernetted-chain theory. This superiority over both integral equation theories is lost, however, at high densities, especially as the widths of the wells and/or the barriers increase.Para Andrés Santos Reyes y Santos Bravo Yuste, este trabajo ha sido financiado por el Gobierno de España, a partir de la beca FIS2010-16587 y de la Junta de Extremadura (España) a partir de la beca GR10158. También han sido parcialmente financiados por fondos FEDER. Pedro Orea ha recibido ayuda del IMP, a partir del Molecular Engineering Progra

Tolerabilidad del resveratrol y efectos sobre parámetros bioquímicos sanguíneos

El resveratrol es un polifenol aislado de la uva al cual se le ha adjudicado actividad terapéutica antitumoral, incremento de longevidad, disminución de peso y protección cardiovascular. Se encuentra disponible como suplemento alimenticio y se vende sin prescripción médica. Evaluar la tolerabilidad de resveratrol, efectos adversos y efectos sobre pruebas de función hepática, renal y perfil de lípidos. Se administró resveratrol 500 mg, vía oral a 8 sujetos sanos durante 30 días y se realizó evaluación clínica, perfil bioquímico y de lípidos al inicio y final del estudio. No se observaron efectos adversos ni alteración en el perfil bioquímico ni de lípidos. El resveratrol fue bien tolerado, mostró ser seguro en dosis diarias de 500 mg, sin embargo se requieren estudios con mayor número de sujetos para confirmarl

Una aplicación de reconocimiento estadístico de patrones a diagnóstico de alteraciones del equilibrio

Se presenta una aplicación de reconocimiento estadlstico de patrones a diagnóstico de alteraciones del equilibrio en tiempo real, actualmente en desarrollo. En el trabajo se pone énfasis en el procesamiento de las señales del paciente utilizando técnicas de tratamiento de imágenes y de redes neuronales aplicadas a reconocimiento estadistico de patrones con el fin de obtener un diagnóstico totalmente automático. Lo aquí expuesto es un análisis complementario al "Diagnóstico por Imágenes de Alteraciones del Equilibrio", el cual se encuentra operativo en consultorio.Eje: Procesamiento de señalesRed de Universidades con Carreras en Informática (RedUNCI

Age of Haemonchus contortus third stage infective larvae is a factor influencing the in vitro assessment of anthelmintic properties of tannin containing plant extracts

The larval exsheathment inhibition assay (LEIA) of infective larvae (L3) is an in vitro method used to evaluate the anthelmintic (AH) activity of tannin-containing plant extracts against different species of gastrointestinal nematodes, including Haemonchus contortus. Some conditions remain to be defined in order to standardize the LEIA, i.e. the optimal age of larvae produced from donor animals to use in the assays. Therefore, this study aimed at identifying the effect of age and age-related vitality of H. contortus infective larvae produced under tropical conditions, on the in vitro AH activity measured with the LEIA. The same acetone:water (70:30) extract from Acacia pennatula leaves was used to perform respective LEIA tests with H. contortus L3 of different ages (1–7 weeks). Each week, the L3 were tested against different concentrations of extract (1200, 600, 400, 200, 100, 40μg/mL of extract) plus a PBS control. Bioassays were performed with a benzimidazole (Bz) resistant H. contortus (Paraíso) strain. In order to identify changes in L3 vitality on different weeks (1–7), two assays testing larval motility were included only with PBS: the larval migration assay (LMA) and the larval motility observation assay (LMOA). Mean effective concentrations causing 50% and 90% exsheathment inhibition (EC50, EC90) were obtained for every week using respective Probit analyses. On the first week, the larvae had lowest EC50 and EC90 (39.4 and 65.6μg/mL) compared to older larvae (P0.05), while older larvae tended to show higher EC50 and EC90 (P<0.05). Motility showed strong negative correlations with age of larvae (r≥−0.83; P <0.05) and EC50 (r≥−0.80; P<0.05), suggesting that the lower extract efficacy could be associated with decaying vitality of larvae associated with age. More stable efficacy results were found between two to five weeks of age

Avaliação de dois níveis de lisina em dietas iniciais para suínos Pelón Mexicano e seu efeito na carcaça e na carne

In the present investigation, the effect on the quality of the carcass and meat of growing Mexican Hairless pigs fed with the inclusion of 100 and 80 % of the lysine requirements recommended by the NRC (2012) in the diet was evaluated. Eight piglets of 12 ± 1.28 kg of the Mexican Hairless breed were used, distributed completely at random in two treatments (T100 and T80) with the covariate effect of slaughter weight, which consisted of balanced diets fulfilling 100 or 80 % of the requirements of lysine established by the NRC. When they reached a live weight of 25 kg, they were slaughtered in a municipal slaughterhouse and the main parameters used to determine the quality of the carcass and meat were evaluated. The treatment effect did not show statistically significant differences (p&gt;0.05) for most of the variables except for the b* color value and Hue tone. Reducing up to 80% of the amount of lysine recommended by the NRC for commercial pigs in the diet does not affect the quality of the carcass and meat in growing Mexican Hairless pigs.En la presente investigación se evaluó el efecto en la calidad de la canal y carne de cerdos Pelón Mexicano en crecimiento alimentados con la inclusión del 100 y 80 % de los requerimientos de lisina recomendados por el NRC (2012) en la dieta. Se utilizaron 8 lechones de 12±1.28 kg de raza Pelón Mexicano de distribuidos completamente al azar en dos tratamientos (T100 y T80) con efecto de covariable el peso al sacrificio, que consistieron en dietas balanceadas cumpliendo el 100 o el 80 % de los requerimientos de lisina establecidos por el NRC. Cuando alcanzaron un peso vivo de 25 kg, fueron sacrificados en rastro y se evaluaron los principales parámetros utilizados para determinar la calidad de la canal y carne. El efecto del tratamiento no mostró diferencias estadísticas significativas (p&gt;0.05) para la mayoría de las variables a excepción del valor de color b* y el tono Hue. Reducir en la dieta hasta un 80% de la cantidad de lisina recomendada por el NRC para cerdos comerciales, en los cerdos Pelón Mexicano en crecimiento no se afecta la calidad de la canal y carne.Na presente investigação, avaliou-se o efeito sobre a qualidade da carcaça e da carne de suínos mexicanos sem pêlo em crescimento alimentados com a inclusão de 100 e 80% dos requisitos de lisina recomendados pelo NRC (2012) na dieta. Foram utilizados oito leitões de 12 ± 1,28 kg da raça Pelón Mexicano, distribuídos totalmente ao acaso em dois tratamentos (T100 e T80) com efeito covariável do peso de abate, que consistiu em dietas balanceadas atendendo 100 ou 80% das exigências. lisina estabelecida pelo NRC. Ao atingirem o peso vivo de 25 kg, foram abatidos no abate e avaliados os principais parâmetros utilizados para determinar a qualidade da carcaça e da carne. O efeito do tratamento não apresentou diferenças estatisticamente significativas (p&gt;0,05) para a maioria das variáveis, exceto para o valor de cor b* e tom Hue. Reduzir até 80% da quantidade de lisina recomendada pelo NRC para suínos comerciais na dieta não afeta a qualidade da carcaça e da carne em suínos Mexicanos Pelados em crescimento

Is there a negative association between the content of condensed tannins, total phenols, and total tannins of tropical plant extracts and in vitro anthelmintic activity against Haemonchus contortus eggs?

In vitro studies using plant extracts suggest a relationship between their polyphenol contents and their anthelmintic (AH) activity against Haemonchus contortus. High polyphenol content appears to increase the efficacy of plant extracts against H. contortus as assessed by the larval exsheathment inhibition assay (LEIA) while appearing to reduce the AH efficacy measured using the egg hatch assay (EHA). In addition, some plants lack AH activity. Therefore, the present study investigated the relationship between the contents of condensed tannins (CT), total phenols (TP), and total tannins (TT) in methanol:water extracts (70:30) obtained from ten tropical plant species consumed by small ruminants as well as their AH activity against H. contortus evaluated by LEIA and EHA. Extracts of Acacia collinsii, Lysiloma latisiliquum, Havardia albicans, Senegalia gaumeri, Mimosa bahamensis, Piscidia piscipula, Acacia pennatula, Gymnopodium floribundum, Leucaena leucocephala, and Bunchosia swartziana were examined. Positive correlations were found between the effective concentration 50% (EC50) (EHA) of extracts and their CT (r = 0.6809, P < 0.05, n = 10) and TP (r = 0.9152, P < 0.05, n = 10) content, suggesting that their concentration negatively affected AH activity against eggs. Based on the LEIA, there was no significant association between the EC50 and the CT, TP, or TT of all extracts evaluated. Thus, if sheep and goats consume a complex feed mixture with high amounts of CT, TP, and TT, it might be difficult to observe an AH effect against H. contortus egg hatching. However, the AH effect upon L3 establishment might be feasible

An in vitro approach to evaluate the nutraceutical value of plant foliage against Haemonchus contortus

Nutraceutical plants provide nutrients for the animal as well as secondary compounds that can affect the biology and survival of gastrointestinal nematodes (GIN). Current screening of nutraceutical plants is based on in vitro evidence of anthelmintic (AH) activity against different life stages of GIN, but nutritional information is omitted or scarce. This study proposes an integral in vitro screening protocol to identify the nutraceutical value of the foliage from plant species consumed by small ruminants, using Haemonchus contortus as a biological model. The leaves from Acacia collinsii, A. pennatula, Bunchosia swartziana, Gymnopodium floribundum, Havardia albicans, Leucaena leucocephala, Lysiloma latisiliquum, Mimosa bahamensis, Piscidia piscipula, and Senegalia gaumeri were evaluated for their chemical composition and in vitro digestibility. Acetone:water extracts (70:30) from leaves of each plant were evaluated using the egg hatch assay and larval exsheathment inhibition assay. Respective effective concentrations 50% (EC50) were determined for each assay. The ten plant species showed good nutritional value for ruminants, including crude protein (> 10%), metabolizable energy (> 2.9 MJ/kg DM), and varied CT content (from 1.0 to 37.6%). The best AH activity against H. contortus eggs (EC50 = 401.8 μg/mL) and L3 (EC50 = 83.1 μg/mL) was observed for S. gaumeri extract. Although all the plant species showed in vitro nutraceutical potential, the leaves of S. gaumeri had the best values. The proposed in vitro protocol showed to be useful for the integral assessment of the nutraceutical potential of different plant species as it included the nutritional value and the AH activity against eggs and L3 in the selected plant species

Deregulated cellular circuits driving immunoglobulins and complement consumption associate with the severity of COVID-19 patients

SARS-CoV-2 infection causes an abrupt response by the host immune system, which is largely responsible for the outcome of COVID-19. We investigated whether the specific immune responses in the peripheral blood of 276 patients were associated with the severity and progression of COVID-19. At admission, dramatic lymphopenia of T, B, and NK cells is associated with severity. Conversely, the proportion of B cells, plasmablasts, circulating follicular helper T cells (cTfh) and CD56–CD16+ NK-cells increased. Regarding humoral immunity, levels of IgM, IgA, and IgG were unaffected, but when degrees of severity were considered, IgG was lower in severe patients. Compared to healthy donors, complement C3 and C4 protein levels were higher in mild and moderate, but not in severe patients, while the activation peptide of C5 (C5a) increased from the admission in every patient, regardless of their severity. Moreover, total IgG, the IgG1 and IgG3 isotypes, and C4 decreased from day 0 to day 10 in patients who were hospitalized for more than two weeks, but not in patients who were discharged earlier. Our study provides important clues to understand the immune response observed in COVID-19 patients, associating severity with an imbalanced humoral response, and identifying new targets for therapeutic interventionThe study was funded by grants SAF2017- 82886-R to FS-M from the Ministerio de Economía y Competitividad, and from “La Caixa Banking Foundation” (HR17-00016) to FS-M. Grant PI018/01163 to CMC and grant PI19/00549 to AA were funded by Fondo de Investigaciones Sanitarias, Ministerio de Sanidad y Consumo, Spain. SAF2017-82886-R, PI018/01163 and PI19/00549 grants were also co-funded by European Regional Development Fund, ERDF/FEDER. This work has been funded by grants Fondo Supera COVID (CRUE-Banco de Santander) to FSM, and “Ayuda Covid 2019” from Comunidad de Madri