Recuperación de variables bioculturales para el diseño de estrategias de sustentabilidad alimentaria

Los pueblos ancestrales que se encuentran alrededor de la Zona Metropolitana de la Ciudad de Toluca (ZMCT) han sufrido cambios culturales y pérdida de la autosuficiencia alimentaria; a partir del desarrollo industrial. El objetivo de la presente investigación fue analizar las variables clave que propician el fortalecimiento de las actividades alternas y complementarias para la sustentabilidad alimentaria. Se aplicó un cuestionario a 70 familias campesinas de San Antonio Acahualco. Se aplicó una entrevista semiestructurada a 20 obreros con raíces campesinas. Los datos se analizaron en el paquete estadístico SPSS (versión 17) para identificar las variables bioculturales que permiten el complemento entre actividades primarias, secundaria y terciaría, a través de la regresión logística. San Antonio Acahualco se localiza al suroeste de la ZMCT, tiene raíz ancestral otomí, su población económicamente activa (5526) labora en la industrial y en los sectores de comercio y servicios. Solamente, el 5% de las familias campesinas complementa dichas actividades con la práctica de la milpa y animales de traspatio. Las variables que resultaron ser significativas son: la organización familiar, edad, sustento familiar, ingreso y ahorro. Se concluye que dichas variables son la base para el diseño de estrategias integrales para recuperar y fomentar la sustentabilidad alimentaria en San Antonio Acahualco.PUEBLOS ANCESTRALES HAN CONTRIBUIDO A LA SEGURIDAD ALIMENTARIA POR MEDIO DE PRÁCTICAS TRADICIONALES COMO ES LA MILPA, LA CRÍA DE ANIMALES DE TRASPATIO Y HUERTOS FAMILIARES, DANDO COMO RESULTADO LA DIVERSIDAD DE PRODUCTOS ALIMENTARIOS QUE SON LA BASE DE LA ALIMENTACIÓN DE LAS FAMILIAS CAMPESINAS POR ESTACIONES DEL AÑO.CONACYT, RETENCIÓN

Diagnóstico de la cobertura de la red wifi en la Universidad de Holguín

En el presente artículo se centra en el analisis, diagnóstico y posible optimización a la red de datos de las dos universidades en donde se realizaron las mediciones de la Wi-Fi, el cual tuvo dos fases: la localización de la red y trazado de los edificios a escala con el objetivo de plantear una mejora para la red. Estas mejoras deben realizarse para la solución de algunos problemas detectados en la mayoría de las zonas de la universidad como deficiencia en el alcance de la Wi-Fi en los edificios. Este problema se detectó en la investigación realizada utilizando un analizador de redes inalámbricas. Los resultados obtenidos fueron que en los dos últimos salones de cada edificio no alcanza la señal de ningún router así como en algunos otros puntos de la misma, la señal de la Wi-Fi es deficiente. Según los resultados obtenidos, una forma de solucionar estos problemas sería la implementación de puntos de acceso inalámbricos en las áreas donde la señal llega deficiente o de otra manera puede ser la reubicación de los dispositivos para que esta señal pueda ser más optima y llegue a las zonas donde su cobertura es muy deficiente y con esto obtendríamos la optimización de la Wi-Fi

The chromatic polynomial of fatgraphs and its categorification

Motivated by Khovanov homology and relations between the Jones polynomial and graph polynomials, we construct a homology theory for embedded graphs from which the chromatic polynomial can be recovered as the Euler characteristic. For plane graphs, we show that our chromatic homology can be recovered from the Khovanov homology of an associated link. We apply this connection with Khovanov homology to show that the torsion-free part of our chromatic homology is independent of the choice of planar embedding of a graph. We extend our construction and categorify the Bollobas-Riordan polynomial (a generalisation of the Tutte polynomial to embedded graphs). We prove that both our chromatic homology and the Khovanov homology of an associated link can be recovered from this categorification.Comment: A substantial revision. To appear in Advances in Mathematic

Valoración mecanotérmica de una resina biodegradable como agente de acoplamiento de materiales compuestos celulósicos/polímero hidrofóbico

En la búsqueda de plásticos reforzados con fibras que sean más amigables con el medio ambiente, aquí se presenta el primer estudio que evalúa la posibilidad de utilizar la brea natural de pino (en forma pura o maleinizada) como agente de acoplamiento (biodegradable). Polipropileno (matriz) y fibra de agave (Agave tequilana) de desecho a diferentes concentraciones (agente de refuerzo), fueron acoplados con cada uno de los agentes utilizados; su efecto en las propiedades mecánicas se comparó con el de un agente comercial de polipropileno modificado (Epolene E-43). Igualmente se prepararon, materiales compuestos sin agente de acoplamiento como referencia genérica. El desempeño mecanodinámico y mecanoestático de los materiales muestra claramente el incremento de propiedades mecánicas con los 3 agentes utilizados. La brea maleinizada mostró similitud o ligera superioridad sobre el agente comercial en el efecto logrado. La afectación en cristalinidad por la presencia de la fibra y el agente de acoplamiento correspondiente, fue evaluada mediante calorimetría diferencial de barrido. La absorción de agua como función del tiempo, permitió medir de forma indirecta el cambio logrado en la superficie de los materiales, y un análisis de FTIR, la valoración de la interacción fibra-polímero obtenida con el agente de acoplamiento. Tal interacción lograda con los agentes de acoplamiento, pudo ser además apreciada utilizando microscopía electrónica de barrido. Los resultados alcanzados marcan el camino para poder usar resinas naturales biodegradables como agentes de acoplamiento en el área de plásticos reforzados con fibras celulósicas. AbstractIn the search of useful environmentally friendly fiber reinforced plastics, this is the first study that evaluates the capability to use natural pine rosin (in pure or maleated glycerol ester form) as a biodegradable coupling agent. Polypropylene as polymer matrix and discarded agave fiber (Agave tequilana) as reinforcing agent at different concentrations, were coupled with each one of the two rosins above mentioned; a commercial maleated polypropylene (Epolene, E-43) agent was used to compare their effect. As generic reference, composites without coupling agent were also tested. Mechanodynamic and mechanostatic tests clearly show an increment in mechanical properties of the composites, using any of the 3 coupling agents. The results obtained with maleated rosin were similar or slightly better than the ones obtained with the commercial agent for composites with high fiber content. Fiber content and coupling agent effect on composites crystallinity, was evaluated by differential scanning calorimetry. In addition, water absorption as a function of time was followed to evaluate the effect of surface modification, and FTIR analysis allowed the observation of the fiber-polymer matrix interaction that was promoted with the coupling agents. The effect of such interaction obtained with the different coupling agents, was observed by scanning electron microscopy. The results show the feasibility to use the natural pine rosin in pure or modified form as biodegradable coupling agents

Estado de México y democracia en los albores del siglo XXI

De acuerdo con su título, este libro, compuesto por seis capítulos y dos anexos, reúne textos relativos a la democracia y al Estado de México, una de las principales entidades federativas de la República Mexicana. La importancia del Estado de México en el contexto nacional es indiscutible: de las 32 entidades que integran el país, es la que tiene más habitantes y electores (el segundo y el tercer lugares en ambos sentidos son ocupados, respectivamente, por el Distrito Federal y Veracruz), en tanto que está en el segundo lugar por el tamaño de su economía (en el primero se ubica el Distrito Federal y en el tercero, Nuevo León)

Sexual propagation of Abies religiosa (Kunth) Cham, by immersion in water at different temperatures and periods

Objective: To increase the percentage of germination in Abies religiosa by immersion in water at different temperatures and times that the seeds will be soaked. Design/methodology/approach: A completely randomized factorial experiment was carried oud with five temperatures (10, Ta, 30, 40 and 50 °C) and 13 times expressed in seconds (10, 20, 40, 60, 600, 1200, 1800, 2400, 3000, 3600, 7200, 14400 and 2160) with a total of 65 treatments and 30 replications of each treatment. The seed were immersed in water at different temperatures and times corresponded to each treatment in order to obtain the best treatment that generated the highest percentage. Results: The best pre-germinative treatment that generated the highest germination percentage was the combination of temperature of 40 °C and a time of 7200s, obtaining 73% germination, and 14% germination as the lowest percentage in the combinations (10 °C x 20s and 10 °C x 40s), generating 26 treatments with percentages higher than 50% germination, registering a peak value of 8.56 and 11.7 days to reach the peak value. Limitations on study/implications: In the experiment, it was important to maintain the different temperatures constant, being those of longer time, lower temperature and higher temperature the most difficult to control and maintain Findings/conclusions: Abies religiosa is able to tolerate and generate acceptable germination percentages with the highest temperature used (50 °C), being one of the best temperatures, which was supposed to generate low germination percentages. Keywords: Germination, Temperature, Time, Peak valueObjective: To increase the germination percentage of Abies religiosa by immersion in water with different temperatures and periods.Design/Methodology/Approach: A completely randomized factorial experiment was carried out with five temperatures (10, Room temperature (Rt), 30, 40, and 50°C) and 13 periods expressed in seconds (10, 20, 40, 60, 600, 1200, 1800, 2400, 3000, 3600, 7200, 14400, and 21600), with a total of 65 treatments and 30 repetitions per treatment. The seeds were dipped in water with the temperatures and periods of each treatment to obtain the highest germination percentage.Results: The best pre-germination treatment (73% germination) was obtained with the combination of 40 °C and 7,200 s. Meanwhile, the treatments with the lowest percentage (14%) were the combinations 10 °C × 20 s and 10 °C × 40 s. Twenty-six treatments recorded a >50% germination, reaching a peak value of 8.56 at 11.7days. Study Limitations/Implications: Keeping the water temperature and theimmersion period constant during the experiment was more difficult in the longer treatments, with the lowest and highest temperatures.Findings/Conclusions: Abies religiosa registers acceptable germination percentages with the highest temperature (50 °C)

Fucoidan-degrading fungal strains: screening, morphometric evaluation, and influence of medium composition

Ten different fungal strains from the genus Aspergillus, Penicillium, and Mucor were screened for fucoidan hydrolyzing ability aiming to find microorganisms able to produce sulfated fucan-degrading enzymes. Screening was carried out by measuring the strains kinetic and morphometric behavior over plate assays using Laminaria japonica fucoidan as only carbon source, testing three nitrogen sources (urea, peptone, and sodium nitrate). The selected fungal strains were subsequently used in submerged fermentations, which were performed for (1) selection of the strains able to growth over fucoidan medium and (2) media selection, testing the synergy of fucoidan with other sugars for inducing high enzyme titles. Radial expansion and hyphae parameters were observed for Aspergillus niger PSH, Mucor sp. 3P, and Penicillium purpurogenum GH2 grown only over fucoidan-urea medium. A. niger PSH showed the maximum enzymatic activity values, which were significantly different (p<0.05) from those achieved by the other selected fungi. Sucrose addition to fucoidan media proportioned the highest fucoidanase activity values for this fungal strain. This research allowed establishing optimal conditions for metabolites synthesis by fungal stains able to act toward fucoidan ramified matrix.Mexican Science and Technology Council (CONACYT

Study of intergenotypic competition in Upland cotton, G. hirsutum L

Includes bibliographical references (leaves 88-91)Competition was evaluated in four population densities to determine its effect on productivity and yield components, and to assess its importance on breeding for narrow-row culture. A mixture of three genotypes, differing in productivity and growth habit, simulated a segregating early generation, handled as a bulk, where individual plants of a given genotype are randomly surrounded by plants of other genotypes, i.t., competition occurred among distinct genotypes. Pure culture plots of the same three genotypes were grown to provide a basis for estimating intragenotypic competition as it occurs in progeny row or pedigree testing. A tall-vigorous genotype (G) was the strongest competitor in the mixture, averaging 42% more seedcotton yield than in pure culture. A semi-dwarf genotype (N) showed a reduction of 12% when growing in mixture. The most productive genotype (E) in pure stand was the weakest competitor, its yield was reduced an average of 12% in mixed culture. Competition affected the percentage of plants selected in the four population densities. As population decreased, the proportion of N and especially E diminished considerable and consequently a larger proportion of G remained. In contrast, E was selected more frequently when planted in pure culture, especially in high population densities. As population decreased and selection pressure was relaxed, similar proportions of the three genotypes were selected. This study suggests that breeding Upland cotton for high population culture might be most effective in narrow-row nurseries and that bulk breeding, at least under irrigated condition, should be avoided

Study of intergenotypic competition in Upland cotton, G. hirsutum L

Includes bibliographical references (leaves 88-91)Competition was evaluated in four population densities to determine its effect on productivity and yield components, and to assess its importance on breeding for narrow-row culture. A mixture of three genotypes, differing in productivity and growth habit, simulated a segregating early generation, handled as a bulk, where individual plants of a given genotype are randomly surrounded by plants of other genotypes, i.t., competition occurred among distinct genotypes. Pure culture plots of the same three genotypes were grown to provide a basis for estimating intragenotypic competition as it occurs in progeny row or pedigree testing. A tall-vigorous genotype (G) was the strongest competitor in the mixture, averaging 42% more seedcotton yield than in pure culture. A semi-dwarf genotype (N) showed a reduction of 12% when growing in mixture. The most productive genotype (E) in pure stand was the weakest competitor, its yield was reduced an average of 12% in mixed culture. Competition affected the percentage of plants selected in the four population densities. As population decreased, the proportion of N and especially E diminished considerable and consequently a larger proportion of G remained. In contrast, E was selected more frequently when planted in pure culture, especially in high population densities. As population decreased and selection pressure was relaxed, similar proportions of the three genotypes were selected. This study suggests that breeding Upland cotton for high population culture might be most effective in narrow-row nurseries and that bulk breeding, at least under irrigated condition, should be avoided