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Simulación númerica de la dispersión de aerosoles producidos por incendios forestales en el área de protección de flora y fauna La Primavera, Jalisco.
Get PDFTesis (Maestría en Ciencias Ambientales)"Los incendios forestales son un problema ambiental global que afecta los ecosistemas forestales del planeta. La quema de biomasa ocasiona daños en la vegetación, pérdida de especies animales, pérdida de cobertura de suelo e influye en la calidad del aire. La quema de biomasa altera los ciclos geoquímicos que existen de manera natural en la atmósfera debido a la emisión de aerosoles que se generan durante los incendios forestales. Los elementos que más predominan durante la quema son el dióxido de carbono (CO2) el monóxido de carbono (CO) el nitrógeno y pequeñas cantidades de dióxido de sulfuro y partículas PM10 y PM2.5. Estos elementos favorecen la formación de niebla toxica que afecta la salud de las personas. Estas nieblas tóxicas o plumas son dispersadas por la circulación atmosférica, pueden alcanzar grandes distancias y afectar grandes regiones. En la Republica Mexicana, los episodios de incendios se han incrementado en los últimos 13 años, llegándose a registrar hasta 15,000 incendios por año y áreas afectadas de hasta 800,000 ha. Estos episodios se concentran principalmente en la Sierra Madre Oriental y al Sur de México. La mayoría de los incendios son inducidos por actividades antropogénicas y favorecidos por eventos climáticos como El Niño. Un ecosistema con incendios recurrentes es el Área de Protección de Flora y Fauna La Primavera (APFFLP) en Jalisco. Un promedio anual de 29 incendios ocurren en el APFFLP. Durante el año 2005, este ecosistema fue impactado por 89 incendios de acuerdo con los datos registrados por el Programa de Monitoreo de Incendios Forestales a cargo de la CONABIO. El evento más devastador que ha sufrido el APFFLP sucedió entre el 25 y 26 de abril de 2005, donde un área de 8478 ha fue devastada por el fuego. Para evaluar la dispersión de los aerosoles emitidos, se aplicó el Modelo de Mesoescala de Quinta Generación (MM5), desarrollado por el Nacional Center for Atmospheric Research (NCAR) y la Universidad de Pensilvania (USA), y el Modelo Químico y Climático de Mesoescala (MCCM),desarrollado por el Instituto Fraunhofer (Alemania).""Forest fires are a global environmental problem that affects many ecosystems in the world. The corresponding burning of biomass causes large vegetation damages, the lost of animal species, land use changes and affect the air quality. The biomass burning alters the natural geochemical cycles in the atmosphere due to the emissions of aerosols generated during the forest fires. The principal substances emitted during the biomass burning are: carbon dioxide (CO2), carbon monoxide (CO), NOx and small quantities of sulphur dioxide and particulate matter PM10 and PM2.5. These chemical substances and other favor the formation of toxic fogs that affect the health of inhabitants. These toxic fogs or plumes are dispersed by the atmospheric circulation and can reach large distances and affect big regions. In Mexico, the number of forest fires increased in the last 13 years, reaching a rate of 15000 fires a year and affecting an area of about 800000 hectares. These fires occur principally in the Mountain Range Eastern Mother and to the South of Mexico. Most of the fires are produced by anthropogenic activities and are favored by climatic events like El Niño phenomenon. An ecosystem underlying recurrently a large number of forest fires is the Protected Area of Flora and Fauna La Primavera (Área de Protección de Flora y Fauna La Primavera) (APFFLP) in the state of Jalisco, Mexico. In averaged, 29 forest fires occur in the APFFLP, but during the year 2005, 89 fires impacted the ecosystem according to data records of the Monitoring Program of Forest Fires of CONABIO (National Commission for the Knowledge and Use of the Biodiversity). The most outstanding event occurred in the APFFLP happened on April 25 and 26 of 2005 when an area of 8478 hectares was devastated by forest fires. To evaluate the dispersion of the emitted aerosols, the models MM5 (Mesoscale Model of fifth Generation), developed by the National Center for Atmospheric Research and the University of Pennsylvania, and MCCM (Mesoscale Climatic and Chemistry Model) developed by the Institute Fraunhofer (Germany), were applied.
Transformant strains of the mycoparasite fungus Trichoderma spp. which promote the growth and resistance to fungal and bacterial diseases in solanaceae plants, composition containing the same, application process and use thereof
No full text"La presente invención describe y reclama cepas transformantes novedosas del hongo Trichoderma ssp., capaces de promover el crecimiento y la resistencia a fitopatógenos en plantas de interés agronómico de una manera significativa en comparación con las cepas convencionales. La utilización de estas cepas disminuyen considerablemente el uso abonos y de pesticidas químicos cuya fabricación y uso dañan el medio ambiente y la salud humana.""The present invention describes and claims novel transformant strains of the Trichoderma ssp fungus, which promote the growth and resistance to phytopathogens in plants of agricultural interests in a significant manner unlike traditional strains. The use of said strains reduces in a substantial manner the application of manures and chemical pesticides which manufacture and usage damage the environment and human health.
Expresión heteróloga de la ATPasa TAA43 y la alcohol deshidrogenasa Ta1316 procedentes de Thermoplasma acidophilum
Get PDF"El reino Archaea constituye uno de los tres dominios en los que se clasifican los seres vivos. Son microorganismos unicelulares carentes de núcleo y organelos. Fueron descubiertas hace 40 años en ambientes con condiciones extremas y desde entonces se les ha encontrado en todo tipo de hábitats. Debido a que varias especies de arqueas son microorganismos extremófilos poseen propiedades inusuales, lo que los convierte en una valiosa fuente de moléculas útiles en procesos biotecnológicos. Además el patrimonio genético de las arqueas es único ya que poseen genes ortólogos en bacterias y eucariontes, aunado a esto su información genética esta contenida dentro de un solo cromosoma circular pequeño (0.49x106 – 5x106 pares de bases). Todas estas características hacen a las moléculas de los microorganismos del reino Archaea modelos de estudio contra organismos más complejos, además de contribuir (biomasa y biocatalizadores) en el mejoramiento y desarrollo de procesos biotecnológicos. Thermoplasma acidophilum es un microorganismo termo-acidofílico del que actualmente se cuenta con su información genética derivada de la secuenciación de su genoma. En este trabajo se realizó la expresión heteróloga de proteínas provenientes de Thermoplasma acidophilum: 1) la ATPasa TAA43 de la familia de proteínas AAA y 2) las proteínas Ta0841 y Ta1316 ADH que presentan identidad con alcohol deshidrogenasas descritas en las bases de datos existentes. En el caso de la proteína recombinante TAA43 se logró la obtención de condiciones idóneas de cristalización para la elucidación de su estructura tridimensional. Por último, se llevó a cabo la caracterización bioquímica de la alcohol deshidrogenasa Ta1316 ADH, la cual por sus características de termoresistencia se propone como un candidato en los procesos de biocatálisis enzimática.""The AAA proteins (ATPases Associated with various cellular Activities) are enzymes found in all kingdoms of life (Archaea, Bacteria and Eukarya) and they are involved in important cellular functions such as proteolysis and unfolding/folding events to mantain homeostasis. The ORF (Open Reading Frame) Taa43 from Thermoplasma acidophilum genome encodes a 43 kDa protein (TAA43) and contains one AAA domain. TAA43 is classified as a member of the AAA protein family. It remains to be clarified the real function of this protein and the three-dimensional structure would help to clarify its contribution in cellular processes. In this work, the AAA TAA43 protein was expressed in Escherichia coli in an amount of 25 mg/l, a purity of 98% and ATPase activity, with the ultimate purpose of carrying on crystalization assays. We were able to identify growth of crystals conditions for TAA43 and the composition confirmed these preliminary results by X-ray diffraction.
Factors causing the mining of aquifers in arid environments: case of San Luis Potosí valley
No full text"El análisis de datos históricos y recientes de hidrogeología, geofísica, cambio de uso del suelo, clima y las prácticas de manejo del recurso hídrico apuntan a una continua disminución de los volúmenes de agua subterránea. Esto revela que el acuífero del Valle de San Luis Potosí se comporta como un recurso minado. El sistema está formado por un acuífero somero en medio granular en depósitos aluviales, un acuífero intermedio de material sedimentario compuesto por gravas, arenas y limos semiconsolidados y un acuífero profundo en un medio fracturado de origen volcánico, denominado Latita Portezuelo. Los factores que afectan negativamente la recarga hacia el valle son: la baja permeabilidad de los materiales rocosos que bordean al valle y que inhiben la infiltración hacia el subsuelo, la baja precipitación y alta evaporación característica de regiones áridas, la erosión de suelos deforestados en las sierras aledañas que impiden la retención de agua, y la construcción de presas en materiales rocosos de baja permeabilidad que reducen drásticamente el flujo de agua a zonas de infiltración en el valle. Adicionalmente, las edades del agua en el medio granular van de 1300 a 2300 años, mientras que en el medio fracturado van de 5300 a 6300 años, indicando ritmos muy lentos de recarga. Los últimos balances hidrogeológicos anuales correspondientes a los años 1995 y 2002 indican que el déficit se incrementó de 36.6×106 a 42.5×106 m3/año. Estos balances coinciden en la existencia de un desequilibrio en la extracción que duplica a la recarga, y dadas las condiciones climáticas del área, conlleva a una condición de minado del agua subterránea en el Valle de San Luis Potosí.""The analysis of historical and recent data on hydrology, geophysics, land use change, climate and water resources management points to a continue decrease of groundwater reserves, which indicates that groundwater mining is taking place in the San Luis Potosi Valley aquifer. The system is formed by a shallow aquifer in a granular medium in alluvial depositions, a middle one of sedimentary material formed by gravels, sands and unconsolidated loams, and a deep aquifer in a volcanic fractured medium, named Latita Portezuelo. The factors negatively affecting the recharge into the valley are: a low permeability of rocky materials surrounding the valley that inhibit the water infiltration into the soil, the scarce precipitation and high evaporation characteristic of arid zones, the soil erosion by deforestation in mountain ranges that prevent water retention, and water dams built on low permeability materials that restrain water runoff to infiltration zones in the valley. Additionally, the ages of the water in the granular aquifer range from 1300 to 2300 years and from 5300 to 6300 years in the fractured aquifer. Hydrogeological balances from 1995 and 2002 show that the deficit has increased from 36.6×106 to 42.5×106 m3/year. These balances reveal a shortage, with extraction doubling the recharge. According to the climatic and geological conditions in the area, the groundwater in the San Luis Potosi Valley reached a condition of mining.
Importance of a tropical tree (Dendropanax arboreus) for Neartic migrant birds in Mexico
Get PDF"En sus sitios reproductivos diversas especies de aves migratorias se alimentan principalmente de insectos, sin embargo, durante su migración en los neotrópicos comen cantidades significantes de frutos. Este estudio a través del análisis y obtención de semillas de restos fecales, observaciones focales de forrajeo, tiempos de retención de semillas en el intestino y porcentajes de germinación de semillas después de pasar por el tracto digestivo, muestra la importancia como recurso alimenticio del árbol tropical Dendropanax arboreus para varias especies de aves migratorias neárticas. Los análisis de muestras fecales mostraron que el 81% de los individuos con excretas que contuvieron semillas de este árbol fueron especies migratorias, principalmente del Zorzal maculado (Hylocichla mustelina), el Maullador gris (Dumetella carolinensis) y el Zorzal de Swainson (Catharus ustulatus). Las observaciones focales, mostraron que el 72% y el 75% de las visitas y de los frutos consumidos respectivamente correspondieron al Maullador gris y al Zorzal maculado. No obstante, el Zorzal de Swainson resultó la especie que permanece más tiempo alimentándose de frutos de D. arboreus. Por otro lado, el Zorzal maculado presentó el mayor tiempo promedio de retención de semillas 56,9 ± 32 min, así como el mayor porcentaje de germinación, mientras que el Zorzal de Swainson presentó el menor tiempo de retención y el menor porcentaje de germinación. En Los Tuxtlas, México los árboles de D. arboreus, se encuentran tanto en zonas conservadas como en perturbadas, y sus frutos constituyen una fuente rica en lípidos para las aves migratorias, mismas que podrían potencialmente dispersar sus semillas a largas distancias, manteniendo con ello la estructura poblacional de este árbol.""Many migratory birds feed insects in their reproductive range while they consume many kinds of fruits during their migration to the Neotropics. We evaluated the importance of fruits of a tropical tree Dendropanax arboreus, as a resource for many species of Nearctic migrant birds. We analyzed fecal samples collected from migratory birds and quantified foraging observations. Also, we compared gutretention times and percentages of germination of seeds defecated by birds. The analyzed fecal samples showed that 81% of them contained seeds of this tree. These fecal samples correspond to migratory birds, mainly Wood Thrush (Hylocichla mustelina), Gray Catbird (Dumetella carolinensis), and Swainson’s Thrush (Catharus ustulatus). Observations showed that 72% and 75% of the visits to trees and of the fruits consumed respectively corresponded to Gray Catbird and Wood Thrush. Nevertheless, Swainson’s Thrush was the species that spent more time feeding on fruits of D. arboreus. On the other hand, Wood Thrush had an average retention time of 56.9 ± 32 min, and seeds that passed through the gut had the highest percentage of germination, while those of Swainson’s Thrush had the least gut-retention time and the smallest percentage of seed germination. In Los Tuxtlas, Mexico, D. arboreus is found in undisturbed and regenerating forests, and its fruits constitute a rich source in lipids for migratory birds. These birds that potentially disperse the seeds of D. arboreus at long distances throughout the landscape, may also maintain the population structure of this tree.
Conditions for synchronization and chaos in networks of β-cells
Get PDF"The insulin producing and releasing pancreatic β-cells play a key role in glucose homeostasis. The proper function of these cells is characterized by a spiking-bursting activity in their membrane potential. It is known that these cells are coupled with each other and that this coupling can induce synchronization. This fact maybe relevant in the mechanisms of blood glucose regulation. However, not much is known about conditions of synchronization, nor about the topology of real-world β-cell network. Also about the conditions for the emergence of chaotic bursting in networks of β-cells not much is known. We investigate these phenomena in terms of complex network theory as model of β-cells networks, in which synchronization and emergence of chaotic bursting occurs.
Loop formation in graphitic nanoribbon edges using furnace heating or Joule heating
Get PDF"Here the authors report the use of either furnace heating or Joule heating to pacify the exposed graphene edges by loop formation in a novel graphitic nanoribbon material, grown by chemical vapor deposition. The edge energy minimization process involves the formation of loops between adjacent graphene layers within the nanoribbons. A comparison is made of the similarities and differences between the loop structures formed using these two methods. An estimation of the temperature of these graphitic nanoribbons during Joule heating is also reported based on the melting and evaporation of Pt nanoparticles.
Online monitoring of Mezcal fermentation based on redox potential measurements
Get PDF"We describe an algorithm for the continuous monitoring of the biomass and ethanol concentrations as well as the growth rate in the Mezcal fermentation process. The algorithm performs its task having available only the online measurements of the redox potential. The procedure combines an artificial neural network (ANN) that relates the redox potential to the ethanol and biomass concentrations with a nonlinear observer-based algorithm that uses the ANN biomass estimations to infer the growth rate of this fermentation process. The results show that the redox potential is a valuable indicator of the metabolic activity of the microorganisms during Mezcal fermentation. In addition, the estimated growth rate can be considered as a direct evidence of the presence of mixed culture growth in the process. Usually, mixtures of microorganisms could be intuitively clear in this kind of processes; however, the total biomass data do not provide definite evidence by themselves. In this paper, the detailed design of the software sensor as well as its experimental application is presented at the laboratory level.
Caracterización molecular de genes de frijol inducidos en la interacción con Rhizoctonia solani.
Get PDFTesis (Maestría en Ciencias en Biología Molecular)"El frijol común (Phaseolus vulgaris L) es una de las leguminosas de mayor consumo en el mundo. Sin embargo, su producción es afectada tanto por factores bióticos como abióticos. La pudrición de raíz del frijol, es una de las enfermedades más importantes que afectan la productividad y desarrollo de este cultivo, además se encuentra ampliamente distribuida en México y en diversas regiones del mundo. Entre los principales agentes causales de la enfermedad destacan Rhizoctonia solani y Fusarium spp. Rhizoctonia solani, es un hongo de distribución cosmopolita nativo del suelo y se ha estimado que puede reducir hasta en un 50% la producción de frijol. Este hongo fitopatógeno puede permanecer por varios años en el suelo en forma de esclerocios (masas compactas de micelio) por lo que es difícil erradicarlo. Para aislar genes de frijol que son diferencialmente expresados durante la interacción incompatible con Rhizoctonia solani, desarrollamos una genoteca sustractiva por medio de la técnica de hibridación substractiva por supresión (SSH). La SSH se realizó empleando el cDNA de raíces de frijol inoculas con Rhizoctonia solani como la condición problema y el cDNA de raíces no inoculadas así como de una proporción de micelio de Rhizoctonia solani crecido por separado como condición control, todos colectados a las 8 y 16 h de interacción.En total se obtuvieron 179 agrupamientos (contigs) que equivalen a 136 genes únicos (uni-genes) de 300 clonas secuenciadas. Estos uni-genes se clasificaron en 12 categorías funcionales, metabolismo primario (10%),metabolismo secundario (12%), defensa (8%), respuesta a estrés (11%),transporte (8%), síntesis de proteínas (6%), componente celular (5%), degradación de proteínas (2%), factores de transcripción (2%), transducción de señales (2%), proteínas de función desconocida (10%) y secuencias sin identidad (24%).""The common bean (Phaseolus vulgaris L) is one of the legumes of greater consumption in the world. However, its production is affected by biotic and abiotic stresses. Common bean root rot, is one of the most important diseases affecting the growth and productivity of this crop, having a wide distribution in Mexico and diverse regions of the world. Among the main causal agents are Rhizoctonia solani and Fusarim spp. Rhizoctonia solani, is a fungus of cosmopolitan distribution native of the soils and it has been estimated that it can reduced up to 50% the production of common bean. This phytopathogenic fungus is able to remain several years in soil in the form of sclerotia (compact mases of hypha) being difficult to eradicate. In order to isolated common bean genes differentially expressed during the incompatible interaction with Rhizoctonia solani, we constructed a Suppresive Substractive Hybridization Library (SSH). The SSH was generated using the cDNA of common bean roots inoculated with Rhizoctonia solani as tester and the cDNA of non-inoculated common bean roots plus a proportion of Rhizoctonia solani micelia as the driver or control condition. All this samples were collected after 8 and 16 h of interaction. From 300 sequenced clones, we obtained a total of 179 contigs equivalent to 136 unigenes. These unigenes were classified in 12 functional categories, primary metabolism (10%), secondary metabolism (12%), defense (8%), response to stress (11%), transport (8%), protein synthesis (6%), cellular component (5%), protein degradation (2%), transcription factors (2%), signal transduction (2%), proteins of unknown function (10%), and sequences with no identity (24%).
Globulin 11S and Its Mixture with l-DPPC at the Air/Liquid Interface
Get PDF"Langmuir films of globulin 11S protein, L-dipalmitoylphosphatidylcholine (L-DPPC), and mixtures of both on water and on buffer subphases were studied. Brewster angle microscopy (BAM) was used to characterize in situ the films morphology along Pi-A isotherms at the air/liquid interface. The L-DPPC monolayer on water behaved as has been reported extensively in the literature but a slight increase on surface pressure and a notable change in domain morphology is observed on buffer. This difference in domain behavior is due to the stabilization interaction of the LE phase by the buffer ions. On the other hand, the protein monolayer was prepared by direct deposit or injection below the surface. Both methods formed mostly a condensed film, with a multilayer formed by globular aggregates in the first method with the two subphases. However, the second method showed different behavior of the protein films depending on the subphase; on water the protein formed a homogeneous film with some globule aggregates, but on buffer a remarkably well-organized monolayer was observed by atomic force microscopy (AFM). Mixtures of globulin 11S and L-DPPC were prepared using both methods for the protein film formation at the air/fluid interface. BAM showed that the mixtures formed coexistence regions between two condensed phases, whose domains of both phases behave like liquids. Fingering phenomena were observed at the interface between protein-rich and L-DPPC-rich domains, which indicates that both phases are fluid. AFM images of the Mixtures show the formation of protein- or L-DPPC-rich domains. The liquidlike behavior could be explained due to different sizes of the protein and the L-DPPC, the minority compound in each kind of domain produces defects making them behave as liquids. Interestingly enough, as the monolayer is compressed to higher surface pressure, the lipid molecules are squeezed out and complete separation of the protein and L-DPPC is produced, Furthermore, we present evidence that the protein/L-DPPC mixtures produce films with holes, which might indicate its tendency to form hollow aggregates that could have some relevance in water-channel formation for in vivo seed germination.