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Hernandez-Hernandez A.A.,Autonomous University of the State of Hidalgo | Alvarez-Romero G.A.,Autonomous University of the State of Hidalgo | Contreras-Lopez E.,Autonomous University of the State of Hidalgo | Aguilar-Arteaga K.,Polytechnic University of Francisco I. timber | Castaneda-Ovando A.,Autonomous University of the State of Hidalgo
Food Analytical Methods | Year: 2017

In the last years, nanotechnology progress has impact several fields of food science. In food analysis, new nanomaterials have been developed in order to extract minority food components. Recently, magnetic nanoparticles (MNPs) have been used as sorbents in methodologies based on dispersive solid-phase microextraction. The main advantage of MNPs as sorbent is their magnetic behavior, which it allows to separate from the food matrix minor components with the aid of a magnet. This MNP property avoids tedious centrifugation and filtration steps, and in turn decreasing sample preparation times and source of errors. The MNPs as sorbent do not need to package in a column, and the separation process is quickly. Other advantages of MNPs in the microextraction of food components are low cost, high concentration factors, and low detection limits; this has allowed the diversification of its applications. Several methods and compounds have been used in the design and functionalization of MNPs, this review focuses in the description of these, especially for the analysis of contaminants (for example, pesticides, heavy metals, drugs, compounds produced during food processing, adulterants, among others). © 2017 Springer Science+Business Media New York

Quero-Carrillo A.R.,Colegio de Mexico | Hemandez-Guzman F.J.,Polytechnic University of Francisco I. timber | Perez-Rodriguez P.,Colegio de Mexico | Pool D.,Instituto Nacional de Investigaciones Nucleares | And 2 more authors.
Revista Fitotecnia Mexicana | Year: 2017

This work evaluated rate of daily germination (RDG) in caryopses classified by size (CCS) and rate of daily emergency (RDE) in both CCS and diaspores in native grasses, Sideoats grama and Blue grama, and introduced grasses, Buffel and Rhodes. Caryopses were obtained from diaspores and classified by size into small, medium and large. All the propagules were tested by 1) accelerated aging tests (AAT) after sowing caryopses on paper and diaspores in peat moss for 12, 24 and 36 h at 42 °C and 100 % HR, and scoring the number of normal seedlings after 15 d; and 2) successful emergence at different sowing depths, by sowing two propagules of each grass at 0.5, 1.0, 2.0, 3.0 and 5.0 cm deep in Vertisol and Calcisol soils, and counting the number of plants after 64 d. The data was analyzed through the LIFEREG (A = 0.05) SAS procedure. Differences were observed in RDG and RDE after TAA for native and introduced grasses (P ≤ 0.001). The highest RDG in Sideoats grama, Blue grama, Buffel grass and Rhodes grass coincided with larger caryopsis, unstressed treatment, and 2 d after sowing (das); yet in native grasses diaspores, highest RDG was obtained from the minimally-stressed treatment, from 4 to 6 das. For introduced grasses, RDG was greater with the minor stress treatment, and it occurred from 6 to 12 d in Buffel and from 5 to 8 d in Rhodes. Sowing depth affected RDE: the highest RDE in any type of propagule was registered between 0.5 and 3.0 cm planting depth, and Vertisol soil promoted higher RDE. Sowing caryopses of larger sizes reduces emergence length and favors establishment of more plants per m2 under rainfed conditions.

Salinas-Rios T.,Benito Juárez Autonomous University of Oaxaca | Sanchez-Torres-Esqueda M.T.,Colegio de Mexico | Diaz-Cruz A.,National Autonomous University of Mexico | Cordero-Mora J.L.,Colegio de Mexico | And 4 more authors.
Revista Colombiana de Ciencias Pecuarias | Year: 2016

Background: it is known that coffee pulp can modify the oxidative status and fertility in dairy cows. Objective: to evaluate the effect of dietary supplementation with coffee pulp on the antioxidant capacity, lipid oxidation and reproductive characteristics of ewes during estrous synchronization and early gestation. Methods: forty Dorset-Suffolk crossbred ewes with 3 or 4 parturitions were allocated to two treatments: T0 (n = 21), ewes supplemented with 450 g of a control feed; and T1 (n = 19), ewes supplemented with 450 g of the feed with 25% coffee pulp. Supplementation began 14 days before estrous synchronization and ended 25 days after breeding. During estrous synchronization, progestogen (CIDR, Controlled Internal Drug Release) was inserted and left in situ for 11 days. Eighteen hours later, estrous detection began with the aid of rams. Blood samples were collected at different times of synchronization and during early pregnancy to determine antioxidant capacity, lipid oxidation and blood progesterone concentration. Pregnancy diagnosis was performed 30 and 60 days after CIDR removal. Results: supplementation with coffee pulp did not affect estrous onset, estrous response or progesterone concentration, but fertility decreased from 100 to 78.95%. The antioxidant capacity measured using the FRAP technique was greater in coffee pulp supplemented ewes only before progestogen insertion. Coffee pulp did not modify lipid oxidation; however, this variable was affected by sampling time, decreasing after progestogen removal to its lowest values at 22 days into pregnancy. Conclusion: although supplementation with coffee pulp at 25% in the concentrate increased antioxidant capacity of ewes before insertion of progestogen, it is not recommended to use this percentage during synchronization or early pregnancy since it can negatively affect gestation rate. © 2016, Universidad de Antioquia. All rights reserved.

Medina-Moreno S.A.,Polytechnic University of Pachuca | Perez-Cadena R.,Polytechnic University of Pachuca | Jimenez-Gonzalez A.,Polytechnic University of Francisco I. timber | Tellez-Jurado A.,Polytechnic University of Pachuca | Lucho-Constantino C.A.,Polytechnic University of Pachuca
Bioresource Technology | Year: 2012

A biodecolorization model that considers the simultaneous mechanism of biosorption and biodegradation of a synthetic dye by immobilized white-rot fungus Trametes subectypus B32 in a fixed bed bioreactor was developed. The model parameters (biokinetic, biosorption and macroscopic transport) were determined by independent experiments. The biodecolorization model was used to determine the effect of variables such as immobilized biomass content, volumetric flow of wastewater, dye feeding concentration and initial dye concentration. By means of the model was possible to predict in the steady state, the limits of immobilized T. subectypus to biodecolorize polluted influent, being the model predictions similar in extent to previous reports. A dimensionless module of biosorption-bioreaction (φ=qmaxvz/rmaxL) was proposed to be used like criterion whenever one of the two mechanisms controls the biodecolorization. The model could be used for the designing and scaling up of fixed bed bioreactors with immobilized white-rot fungi for the biodecolorization process. © 2012 Elsevier Ltd.

Rodriguez-Ortega A.,Polytechnic University of Francisco I. timber | Pino-Moreno J.M.,National Autonomous University of Mexico | Angeles-Campos S.C.,National Autonomous University of Mexico | Garcia-Perez A.,National Autonomous University of Mexico | And 2 more authors.
Revista Colombiana de Entomologia | Year: 2016

The objective of this study was to compare the nutritional quality of larvae and pupae of the silkworm (Bombyx mori). A proximal analysis was performed on: energy (kcal/kg), minerals (%), protein (%), and in vitro digestibility of larvae and pupae of Bombyx mori on wet and dry bases. One hundred (100) larvae and 100 pupae produced under laboratory conditions in July and August 2013 were used. Analysis was performed one month after collection in the laboratory of the Department of Animal Nutrition and Biochemistry of the Faculty of Veterinary Medicine of the National Autonomous University of Mexico. According to statistical analysis, on dry bases, the pupae showed higher energy (4231.89 kcal/kg), mineral (6.25%), protein (64.31%), and fat extract (20.63%) content; as compared with larval energy (4115.79 kcal/kg), mineral (5.02%), protein (62.60%), and fat extract (12.90%) content. Silkworm larvae and pupae are ingredients for the production of cattle rations and the preparation of conventional foods that are rich in protein, fat, and minerals. © 2016, Sociedad Colombiana de Entomologia. All rights reserved.

Garcia-Lopez M.C.,Autonomous University of Nuevo León | Munoz-Flores B.M.,Autonomous University of Nuevo León | Chan-Navarro R.,Autonomous University of Nuevo León | Jimenez-Perez V.M.,Autonomous University of Nuevo León | And 5 more authors.
Journal of Organometallic Chemistry | Year: 2016

Here we report a green one-pot microwave-assisted synthesis of four push-pull organotin complexes derived from Schiff bases in good yields, which provides advancement over conventional method as it is simple, cost-effective and reproducible. All compounds were characterized by UV-Vis, TOF-HRMS, TGA-DTA, cyclic voltammetry, theoretical studies and compound 1 by X-ray single-crystal diffraction. Third-order nonlinear susceptibility χ(3) of complexes 1-4; ((E)-N′-(4-(diethylamino)-2-hydroxysalicylidine) nitrobenzohydrazidatediphenyl-tin (IV) (1), (E)-N′-(4-(diethylamino)-2-hydroxysalicylidine) nitrobenzohydrazidate di n-butyl-tin (IV) (2), ((E)-N′-(4-(methoxy)-2-hydroxysalicylidine) nitrobenzohydrazidate diphenyl-tin (IV) (3), (E)-N′-(4-(methoxy)-2-hydroxysalicylidine) nitrobenzohydrazidate di n-butyl-tin (IV) (4)) were measured via Maker-Fringes technique. In particular, compounds 1 and 2 display larger third-order nonlinearities than their methoxilated counterparts. © 2016 Elsevier B.V. All rights reserved.

Fonseca-Gonzalez J.,Autonomous University of the State of Hidalgo | de los Santos-Posadas H.M.,Colegio de Mexico | Rodriguez-Ortega A.,Polytechnic University of Francisco I. timber | Rodriguez-Laguna R.,Autonomous University of the State of Hidalgo
Agrociencia | Year: 2014

Forest ecosystems are susceptible to wildfires, whose effects may vary greatly depending on their intensity and severity, causing changes in vegetation and biological activity. Infestation of bark beetles is one of the major consequences. The objective of this study was to analyze insect colonization and Pinus patula mortality following a forest fire in a regeneration area using logistic regression. Follow-up lasted 16 months at the municipality of Cuautepec de Hinojosa, state of Hidalgo, México. The variables assessed on trees were percentage of scorched crown, percentage of trunk circumference with evidence of entry of bark beetles of the genus Ips, number of pitch tubes caused by insects of the genus Dendroctonus, evidence of colonization by wood borers, and whether the tree was alive or dead. Of the insects that colonized trees killed by the fire, 99 % were secondary bark beetles: Ips integer, I. bonanseai, I. cribricollis, Pseudips mexicanus and Pityophthorus sp. One was an ambrosia beetle Gnathotrichus sp. In live trees after the forest fire, there was also evidence of attack by Dendroctonus valens and D. mexicanus. There was a strong relationship between fire damage and subsequent presence of insects; more than 82 % of the scorched trees exhibited evidence of colonization, and only 6 % of undamaged trees were successfully colonized. Tree mortality increased with higher percentages of crown scorch, as did infestation by Dendroctonus and Ips: a tree 15 cm in diameter with half of its crown scorched has a 4.5 % probability of dying, which increases to 51 % when bark insect infestation is added to the model.

Lara-Viveros F.M.,Polytechnic University of Francisco I. timber | Ventura-Maza A.,Polytechnic University of Francisco I. timber | Ehsan M.,King Abdulaziz University | Rodriguez-Ortega A.,Polytechnic University of Francisco I. timber | And 2 more authors.
Revista Internacional de Contaminacion Ambiental | Year: 2015

Heavy metals have had many industrial uses for hundreds of years and consequently these elements can be found in dangerous concentrations in the environment. Two of the most toxic metals are Cd and Zn that cause various human diseases. The Mesquital Valley region in the state of Hidalgo is characterized by the use of wastewater for agricultural purposes, but it is likely that these waters contain heavy metals that may be absorbed by plants through irrigation water. The aim of this work was to determine the Cd and Pb amount and their mobility within the plant. Two maize, two sunflower and one alfalfa variety including soil were sampled. The plants were cut and divided into three equal thirds and the concentrations of the two metals were determined in the soil and in each of the fractions in which the plant was divided. Corn Cd values were statistically equal in each of the three thirds (0.06 mg/kg), this value being lower than that observed in soil (0.09 mg/kg). The same behavior was observed in the case of Pb. The alfalfa Cd concentration in the plant was higher than that found in the soil (0.07 mg/kg in the first third of the plant and 0.03 mg/kg soil), while the lowest concentrations for both metals were found in the sunflower. © 2015, Centro de Ciencias de la Atmosfera, UNAM. All rights reserved.

Castaneda-Ovando A.,Autonomous University of the State of Hidalgo | Castaneda-Ovando A.,Polytechnic University of Francisco I. timber | Galan-Vidal C.A.,Autonomous University of the State of Hidalgo | Pacheco L.,Autonomous University of the State of Hidalgo | And 2 more authors.
Food Analytical Methods | Year: 2010

The anthocyanic composition of pigmented Mexican corn (Zea mays) has been investigated. Two extracts (hydrolyzed and non-hydrolyzed) were analyzed by HPLC at different temperatures. The separation profile obtained in chromatography was different for minor components but the main fraction was the same in both cases. The last anthocyanin fraction was collected and analyzed by MALDI-ToF MS. The compounds identified in the fraction were cyanidin-3-glucoside and pelargonidin-3-glucoside with an approximate content of 1 × 10 -6 and 1 × 10 -7 M for the hydrolyzed and non-hydrolyzed, respectively. © Springer Science + Business Media, LLC 2008.

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