Polytechnic University of Francisco I. timber

Tepatepec, Mexico
Time filter
Source Type

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.

Ontiveros G.,Polytechnic University of Francisco I. timber | Hernandez P.,Polytechnic University of Francisco I. timber | Ibarra I.S.,Autonomous University of the State of Hidalgo | Dominguez J.M.,Polytechnic University of Francisco I. timber | Rodriguez J.A.,Autonomous University of the State of Hidalgo
ECS Transactions | Year: 2017

A novel and sensitive biosensor electrochemical was designed and developed and applied in the gluten detection by chronoamperometry in food samples. Protease enzyme was electrodeposited on carbon electrode modified with nanoparticles of fullerene increasing the selectivity and surface area of electrode. Variables involved in the electrochemical system were optimized by a univariate design.Optimal conditions were: pH solution of 7.0, potential -0.7 V, enzyme immobilized (U) of 0.6.Under optimal conditions of analysis was obtained a linear range from 1.7-8.3 mg L-1, with a limit of detection of 0.54 mg L-1, repeatability and reproducibility was evaluated at two spiked levels (5.0 and 7.0 mg L-1) with relative standard deviation less than 10% in all cases. The proposed method was applied to analyze gluten in food samples based in cereals grains. The biosensor offers advantages in terms of simplicity, low cost, short analysis time, making it an alternative for analysis of gluten in matrix complex. ©The Electrochemical Society.

Ponce-Lira B.,Polytechnic University of Francisco I. timber | Otazo-Sanchez E.M.,Autonomous University of the State of Hidalgo | Reguera E.,National Polytechnic Institute of Mexico | Acevedo-Sandoval O.A.,Autonomous University of the State of Hidalgo | And 2 more authors.
International Journal of Environmental Science and Technology | Year: 2017

Pb-contaminated water is a dangerous threat occurring near metallurgic and mining industries. This circumstance produces serious environment concern, due to Pb(II) high toxic effects. Several reactive materials have been reported for Pb(II) adsorption, but not all reached final Pb(II) suitable concentrations, or they are expensive and rejected in massive remediation technologies; hence, natural materials are good options. The adsorption behavior of a volcanic scoria (two sieved fractions 1425 and <425 µm) was studied toward synthetic Pb(II) water solutions in batch experiments (170.4–912.3 mg L−1) with high removal efficiencies (97%). The Langmuir model fits both fractions with high linear correlation coefficients (0.9988 and 0.9949) with high maximum capacity values (588.23 and 555.55 mg g−1). Separation factor RL parameter varies with initial concentration, and the empirical equation predicts the limits of the material usefulness, a criterion proposed in this paper for conditions’ selection. The Lagergren pseudo-second-order analysis demonstrates chemisorption; calculated rate constant (416.66 mg g−1 min−1). Weber–Morris intraparticle model proves that the adsorption phenomena occur fast on the material surface (kinst = 72 g mg−1 min−0.5). The characterization of the volcanic material afforded the elemental composition (X-ray fluorescence), and the empirical formula was proposed. X-ray diffraction patterns verify the material structure as basalt, with a plagioclase structure that matches anorthite and albite, mostly composed of quartz. The presence of oxides on the material surface explain the high Pb(II) adsorption capacity, observed on the surface by scanning electronic microscopy. The studied volcanic scoria has potential use as a Pb(II) adsorbent in water remediation technologies. © 2017, Islamic Azad University (IAU).

Ferreira T.A.,Autonomous University of the State of Hidalgo | Rodriguez J.A.,Autonomous University of the State of Hidalgo | Paez-Hernandez M.E.,Autonomous University of the State of Hidalgo | Guevara-Lara A.,Autonomous University of the State of Hidalgo | And 2 more authors.
Materials | Year: 2017

An evaluation of the chromium(VI) adsorption capacity of four magnetite sorbents coated with a polymer phase containing polymethacrylic acid or polyallyl-3-methylimidazolium is presented. Factors that influence the chromium(VI) removal such as solution pH and contact time were investigated in batch experiments and in stirred tank reactor mode. Affinity and rate constants increased with the molar ratio of the imidazolium. The highest adsorption was obtained at pH 2.0 due to the contribution of electrostatic interactions. © 2017 by the authors.

Acuna-Soto J.A.,Colegio de Mexico | Estrada-Venegas E.G.,Colegio de Mexico | Equihua-Martinez A.,Colegio de Mexico | Vazquez-Rojas I.M.,Laboratorio Of Acarologia Anita Hoffmann | And 3 more authors.
Southwestern Entomologist | Year: 2017

This study presents information about on eriophid mites species associated to three families of trees of forest importance in Mexico. Twenty-six species of 12 genera were found. The highest richness of species was the Eriophyidae family (13), followed by Phytoptidae (eight), and Diptilomiopidae (five). Pinaceae and Fagacea are families with the most eriophyids hosts (11 spp.), followed by Cupressaceae (4 spp.). There are nine genera and 26 species that are new records for Mexico, 16 of them extended the range of hosts and two are new records for North America. The damage, chlorosis, erineos, and malformation of needles and vegetative shoots, caused by eriofidos ranged between 5 and 45%. This study highlights the importance of inventories to know the diversity of eriophids in Mexico and the relationship they have with their hosts. This group of mites is not well known in Mexico.

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.

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.

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.

Loading Polytechnic University of Francisco I. timber collaborators
Loading Polytechnic University of Francisco I. timber collaborators