Vazquez-Garcia M.,University of Guadalajara |
Garabito-Espinoza S.,University of Guadalajara |
Tabares-Vega J.,University of Guadalajara |
Castillo-Herrera G.,Research Center y Asistencia
Acta Horticulturae | Year: 2011
This piece of work was made to characterize physical and chemical properties of essential oils extracted from four aromatic plants species collected in Mexico according to international norms. It was additionally of interest, to determine analytically their compounds and contents. Finally, to study insecticide potential on first instar wild cochineal, an important cactus pest in México. Oils were extracted by means of steam distillation and characterization was made according to international norms AFNOR NA T-101, NA T 75-112 (ISO 280-1976) and NF V 75-113 (ISO 592-1981). Qualitative and quantitative determinations of compounds were made with a Hewlett Packard Gas Chromatograph 5890 Model series II (Palo Alto, Ca.), connected to a Mass Selective Detector Hewlett Packard Model 5972. The insecticide effect was determined by means of bioassay on first instar larvae mobile juveniles and regression parameters calculated using Probit Analysis. Results showed that physical and chemical characteristics of extracted oils fulfill international norms. Most important compounds found in mint: limonene (15%), carvone (61%), in sweet basil: estragole (20%) and linalool (30%), in origanum: p-cymeno (21%) and carvacrol (43%), finally in citronella were found endo-1-bourbonanol (12%), citronelol (13%), elemol (17%) and citronelal (40%). The mean lethal concentration (LC 50) of the mint oil in cochineal mobile juveniles was 7,200 ppm, albacar, 21.600, whereas origanum and citronella showed much greater LC 50 values (46.000 and 59.400, respectively). As compared to LC 50 value (1,800 ppm) of tested conventional insecticide mineral oil SAF-T-SIDE (Monterrey-Lawn and Garden Products Inc) mint LC 50 value showed Relative Insecticidal Effect = 4X which means less insecticide effect than the conventional insecticide. This result suggests mint essential oil as a prospect to be used as a natural control agent for this cactus pest.
Avila-Gonzalez D.,Instituto Nacional Of Perinatologia |
Vega-Hernandez E.,Instituto Nacional Of Perinatologia |
Regalado-Hernandez J.C.,Instituto Nacional Of Perinatologia |
De la Jara-Diaz J.F.,Instituto Nacional Of Perinatologia |
And 9 more authors.
Stem Cell Research | Year: 2015
Data from the literature suggest that human embryonic stem cell (hESC) lines used in research do not genetically represent all human populations. The derivation of hESC through conventional methods involve the destruction of viable human embryos, as well the use of mouse embryonic fibroblasts as a feeder layer, which has several drawbacks. We obtained the hESC line (Amicqui-1) from poor-quality (PQ) embryos derived and maintained on human amniotic epithelial cells (hAEC). This line displays a battery of markers of pluripotency and we demonstrated the capacity of these cells to produce derivates of the three germ layers. © 2015.
Evangelista-Martinez Z.,Research Center y Asistencia |
Imbert-Palafox J.L.,Autonomous University of the State of Hidalgo |
Becerril-Flores M.A.,Autonomous University of the State of Hidalgo |
Gomez-Gomez J.V.,Autonomous University of the State of Hidalgo
Neotropical Entomology | Year: 2010
Triatoma barberi Usinger is a widely recognized vector of the protozoa Trypanosoma cruzi. The determination of its presence in the rural houses is made by direct observation of adults, nymphs, exuviae or eggs. For this reason, egg structural characteristics could facilitate the differentiation and identification of species that inhabit such environments. In here, the morphologic characteristics of eggs of T. barberi are described and analyzed with special attention to the anterior pole of the egg. The structural analysis of eggs by scanning electron microscopy (SEM) showed the presence of a wide and rough chorion edge, which contain aeropyles and micropyles. A deep spermatic canal between the endochorion and exochorion, and a trabecular network in the interior were also observed. The operculum showed cells with irregular growth and undefined polygonal shape. Externally, the operculum cells forms two rings of projections that surround a single extension located to the center. The cellular projections resemble respiratory horns, although the presence of aeropyles was not observed. The chorion structural characteristics can help to identify and separate close species in the Triatominae subfamily.
Espinosa-Andrews H.,Research Center y Asistencia |
Urias-Silvas J.E.,Research Center y Asistencia
Carbohydrate Polymers | Year: 2012
Thermal properties of agave (A. tequilana Weber var. Azul) at different water contents were investigated. HP-TLC results showed a complex mixture of mono-, di-, oligo, and polysaccharides in agave fructans samples. The thermal decomposition temperatures were observed below to 200 °C. Modulated-differential scanning calorimetry studies showed a glass transition and a relaxation enthalpy processes in agave fructans. Samples with the highest moieties of monosaccharides showed the lower glass transition temperatures (T g). The moisture sorption isotherm of agave fructans was determined at 20 °C and fitted to the GAB model. Gordon-Taylor equation was used to fit the T g experimental data as a function of water content. Agave fructans was found to be an amorphous material. At low water activity (a w) values (<0.4), agave fructans remained in a powdered amorphous state; and at intermediate a w (0.4-0.75) collapsed and caked; and at high a w (>0.75) changed in a highly viscous liquid-like solution. © 2011 Elsevier Ltd.
Murillo-Tovar M.A.,Autonomous University of the State of Morelos |
Murillo-Tovar M.A.,National Autonomous University of Mexico |
Saldarriaga-Norena H.,Autonomous University of the State of Morelos |
Hernandez-Mena L.,Research Center y Asistencia |
And 6 more authors.
Atmosphere | Year: 2015
This study was conducted from May 25 to June 6, 2009 at a downtown location (Centro) and an urban sector (Miravalle) site in the Metropolitan Zone of Guadalajara (MZG) in Mexico. The atmospheric concentrations of PM2.5 and its elemental and inorganic components were analyzed to identify their potential sources during the warm dry season. The daily measurements of PM2.5 (24 h) exceeded the WHO (World Health Organization) air quality guidelines (25 μg.m-3). The most abundant element was found to be Fe, accounting for 59.8% and 72.2% of total metals mass in Centro and Miravalle, respectively. The enrichment factor (EF) analysis showed a more significant contribution of non-crustal sources to the elements in ambient PM2.5 in Centro than in the Miravalle site. Particularly, the highest enrichment of Cu suggested motor vehicle-related emissions in Centro. The most abundant secondary ionic species (NO3-; SO4 2- and NH4 +) and the ratio NO3-/SO4 2- corroborated the important impact of mobile sources to fine particles at the sampling sites. In addition, the ion balance indicated that particles collected in Miravalle experienced neutralization processes likely due to a higher contribution of geological material. Other important contributors to PM2.5 included biomass burning by emissions transported from the forest into the city. © 2015 by the authors.