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San Miguel Xico, Mexico

Rubio J.D.J.,Instituto Polite cnico Nacional | Silva Ortigoza R.,National Polytechnic Institute of Mexico
IEEE Latin America Transactions | Year: 2015

Odor identification is an important area in a wide range of industries like cosmetics, food, beverages and medical diagnosis among others. Odor detection could be done through an array of gas sensors conformed as an electronic nose where a data acquisition module converts sensor signals to a standard output to be analyzed. To facilitate odors detection a system is required for the identification. This paper presents the results of an automated odor identification process implemented by a fuzzy system and an electronic nose. First, an electronic nose prototype is manufactured to detect organic compounds vapor using an array of five tin dioxide gas sensors, an arduino uno board is used as a data acquisition section. Second, an intelligent module with a fuzzy system is considered for the identification of the signals received by the electronic nose. This solution proposes a system to identify odors by using a personal computer. Results show an acceptable precision. © 2003-2012 IEEE.

Chang Y.L.,China Agricultural University | Yu Wang J.,China Agricultural University | Tao Wang E.,Instituto Polite cnico Nacional | Can Liu H.,CAS Institute of Microbiology | And 2 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2011

Five strains isolated from root nodules of Lablab purpureus and Arachis hypogaea grown in the Anhui and Sichuan provinces of China were classified as members of the genus Bradyrhizobium. These strains had identical 16S rRNA gene sequences which shared 99.48%, 99.48% and 99.22% similarity with the most closely related strains of Bradyrhizobium jicamae PAC68 T, Bradyrhizobium pachyrhizi PAC48T and Bradyrhizobium elkanii USDA 76 T, respectively. A study using a polyphasic approach, including 16S rRNA gene RFLP, IGS-RFLP, BOX-PCR, comparative sequence analysis of the 16S-23S rRNA intergenic spacer (IGS) and the recA, atpD and glnII genes, DNA-DNA hybridization and phenotypic tests, showed that the five strains clustered into a coherent group that differentiated them from all recognized species of the genus Bradyrhizobium. Sequencing of nifH and nodC genes and cross-nodulation tests showed that the representative strains CCBAU 23086 T, CCBAU 23160 and CCBAU 61434, isolated from different plants, had identical nifH and nodC gene sequences and were all able to nodulate Lablab purpureus, Arachis hypogaea and Vigna unguiculata. Based upon these results, the name Bradyrhizobium lablabi sp. nov. is proposed for this novel species and strain CCBAU 23086 T (5LMG 25572T5HAMBI 3052 T) is designated as the type strain. The DNA G+C mol% is 60.14 (T m). © 2011 IUMS.

Rodriguez-Avila N.L.,Research Center Cientifica Of Yucatan Ac Calle 43 No 130 | Narvaez-Zapata J.A.,Instituto Polite cnico Nacional | Ramirez-Benitez J.E.,Research Center Cientifica Of Yucatan Ac Calle 43 No 130 | Aguilar-Espinosa M.L.,Research Center Cientifica Of Yucatan Ac Calle 43 No 130 | Rivera-Madrid R.,Research Center Cientifica Of Yucatan Ac Calle 43 No 130
Journal of Experimental Botany | Year: 2011

Carotenoid cleavage dioxygenases (CCDs) are a class of enzymes involved in the biosynthesis of a broad diversity of secondary metabolites known as apocarotenoids. In plants, CCDs are part of a genetic family with members which cleave specific double bonds of carotenoid molecules. CCDs are involved in the production of diverse and important metabolites such as vitamin A and abscisic acid (ABA). Bixa orellana L. is the main source of the natural pigment annatto or bixin, an apocarotenoid accumulated in large quantities in its seeds. Bixin biosynthesis has been studied and the involvement of a CCD has been confirmed in vitro. However, the CCD genes involved in the biosynthesis of the wide variety of apocarotenoids found in this plant have not been well documented. In this study, a new CCD1 gene member (BoCCD1) was identified and its expression was charaterized in different plant tissues of B. orellana plantlets and adult plants. The BoCCD1 sequence showed high homology with plant CCD1s involved mainly in the cleavage of carotenoids in several sites to generate multiple apocarotenoid products. Here, the expression profiles of the BoCCD1 gene were analysed and discussed in relation to total carotenoids and other important apocarotenoids such as bixin. © 2011 The Author.

Cordoba E.,National Autonomous University of Mexico | Porta H.,National Autonomous University of Mexico | Arroyo A.,National Autonomous University of Mexico | Arroyo A.,Instituto Polite cnico Nacional | And 4 more authors.
Journal of Experimental Botany | Year: 2011

The 1-deoxy-D-xylulose 5-phosphate synthase (DXS) enzyme catalyses the first biosynthetic step of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. In plants the MEP pathway is involved in the synthesis of the common precursors to the plastidic isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate, in plastids. DXS is recognized as limiting this pathway and is a potential target for manipulation to increase various isoprenoids such as carotenoids. In Zea mays three dxs genes exist that encode plastid-targeted functional enzymes. Evidence is provided that these genes represent phylogenetically distinctive clades conserved among plants preceding monocot-dicot divergence. There is differential accumulation for each dxs gene transcript, during development and in response to external signals such as light. At the protein level, the analysis demonstrates that in Z. mays, DXS protein is feedback regulated in response to the inhibition of the pathway flow. The results support that the multilevel regulation of DXS activity is conserved in evolution. © 2010 The Author(s).

Torres-Torres C.,Instituto Polite cnico Nacional
Nanotechnology | Year: 2015

Due to their selective and fascinating effects, metallic nanoparticles have become a very significant topic for science. A modification in morphology and structure of low-dimensional materials can result in extraordinary ultrafast physical phenomena. New findings related to electronic, optical and magnetic processes have emerged from surface plasmon resonance excitations in nanoparticles. Moreover, multi-functional systems can be obtained from the integration of different elements in a nanostructured configuration. Recently, Palmero et al (2015 Nanotechnology 26 461001) have reported magneto-optical Kerr effect explorations in individual FeCuCo nanowires; the influence of tailored morphologies exhibited by particular samples was analyzed. An important magnetization reversal action was revealed and it was concluded that the demagnetization may be responsible for vortex domain wall propagation. The report can provide a solid base for future research and immediate applications in modern spintronics or magnetic data storage can be contemplated. © 2016 IOP Publishing Ltd.

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