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Análisis de las condiciones meteorológicas de mesoescala en la incidencia de tornados en México
Get PDF"Se presentan los resultados de una investigación sobre las condiciones meteorológicas de mesoescala imperantes en diez distintos casos de tornados sobre el territorio mexicano. Por medio de una estadística actualizada, se reportan los eventos de tornado ocurridos en México durante los últimos 16 años. La investigación se dividió en tres pasos; primeramente la búsqueda y recopilación de eventos de tornado en el país. Los datos recopilados sirvieron de base para la elaboración de una cartografía y gráficos de !distribución espacial y temporal.Un total 54 eventos de tornados fueron recopilados, mismos que se anexaron a los 138 existentes. El siguiente paso fue simular las condiciones meteorológicas numéricamente de 10 eventos diferentes de tornados en el país aplicando el Weather Research and Forecasting Model (Modelo! WRF). Posteriormente, los resultados arrojados por el modelo se analizaron y se efectuó la interpretación de la meteorología de! mesoescala existente en los casos mencionados anteriormente. El tercer pasó consistió en la comparación de las variables analizadas mediante gráficos superficiales y cortes verticales. Este proceso fue complementado con información meteorológica de niveles sinópticos que fueron proveídos por imágenes satelitales interpretadas del Servicio! Meteorológico Nacional (SMN). Las variaciones de temperatura, húmedad, vorticidad potencial y velocidad del viento en la vertical se ven influenciados fuertemente por la orografía. Esta investigación permitió obtener una primera idea sobre las condiciones meteorológicas bajo las cuales ocurren los tornados en México. Los resultados obtenidos revelan esencialmente dos formas de ocurrencia; los derivados de superceldas como en los Estados Unidos de América y los que ocurren en zonas topográficamente complejas con vientos convergentes y divergentes, catabáticos y anabáticos y que requieren una investigación más profunda.""Results of a research work about mesoscale meteorological conditions prevailing
in ten different cases of tornadoes over Mexican territory is presented. An updated statistic over tornado events, occurred in Mexico during the last 16 years, was also carried out. This research was divided into three steps: the first step was the compilation of tornado events in Mexico. The collected data provided the basis for developing a cartography of spatial and temporal distributions of tornadoes. A total of 54 tornado events were collected which were added to the existing 138 from a previous classification. The next step was the numerical simulation of the weather conditions of ten different tornado events in different parts of the country using the Weather Research and Forecasting Model (WRF Model). The results obtained from the model were analyzed and an interpretation of the resulting mesoscale meteorology was performed. The variables analyzed by surface and vertical cross section were compared. This process was complemented by synoptic information provided by interpreted satellite images from the National Weather Service of Mexico (SMNXMexico). Vertical variations of temperature, relative humidity potential vorticity and wind speed are strongly influenced by topography. This research allowed obtaining a first idea of the weather conditions under which tornadoes occur in Mexico. The results reveal essentially two ways of occurrence of tornadoes: supercell tornadoes as it often happens in the United States of America, and those occurring in topographically complex areas with convergent and divergent wind fields, anabatic and katabatic winds which requires further research.
The human diabetes proteome project (HDPP): the 2014 update
Get PDF"Diabetes is an increasing worldwide problem leading to major associated health issues and increased health care costs. In 2012, 9.3% of the American population was affected by diabetes, according to the American Diabetes Association, with 1.7 million of new cases since during the year (www.diabetes.org). Proteome initiatives can provide a deeper understanding of the biology of this disease and help develop more effective treatments. The collaborative effort of the Human Diabetes Proteome Project (HDPP) brings together a wide variety of complementary resources to increase the existing knowledge about both type 1 and type 2 diabetes and their related complications. The goals are to identify proteins and protein isoforms associated with the pathology and to characterize underlying disease-related pathways and mechanisms. Moreover, a considerable effort is being made on data integration and network biology. Sharing these data with the scientific community will be an important part of the consortium. Here we report on: the content of the HDPP session held at the 12th HUPO meeting in Yokohama; recent achievements of the consortium; discussions of several HDPP workshops; as well as future HDPP directions as discussed at the 13th HUPO congress in Madrid, with a special attention given to the lists of prioritized, diabetes-related proteins and the proteomic means to study them.
Estudio de mapeos caóticos discretos y su aplicación en criptografía
Get PDF"La seguridad de la información digital cada vez tiene más auge, debido al creciente uso de dispositivos móviles, además del incremento de operaciones realizadas a través de internet. Esto representa un gran reto ya que para lograr la confidencialidad, integridad y autentificación es necesario el uso de mecanismos especializados, una forma de proporcionar estos servicios es por medio de la criptografía, sin embargo, la creciente demanda requiere de nuevos algoritmos que sean más rápidos y a su vez más seguros. Una opción para lograr estos objetivos es la criptografía basada en sistemas caóticos. Este trabajo de tesis se presenta en tres partes, en la primera parte se muestran los conceptos y definiciones básicas de las ¿áreas de criptografía y sistemas dinámicos, así como las herramientas que se tienen para estudiar cada uno de estos sistemas. Además se da una visión general de estas áreas así como una clasificación, de tal forma que nos enfocaremos en cifrados en flujo y en sistemas dinámicos de tiempo discreto. Cabe señalar que los sistemas dinámicos estudiados en este trabajo a diferencia del mapeo logístico y casa de campaña son multi-modales, los cuales presentan ciertas ventajas en comparación con los mapeos uni-modales. Posteriormente se analizan las similitudes y diferencias que se encuentran en estas dos áreas, dando lugar a la criptografía caótica, la cual ha sido objeto de estudio por diversos grupos de investigación en los últimos años. En la segunda parte de este trabajo se proponen metodologías para construir dos generadores pseudo-aleatorios, los cuales son la parte fundamental en el uso de cifrados en flujo, por un lado se propone el uso de valores positivos y negativos en el parámetro de bifurcación del mapeo logístico en conjunto con retardos, de esta forma es posible construir un generador que muestra resultados satisfactorios a las pruebas estadísticas de aleatoriedad propuestas por el NIST y además no es posible reconstruir el espacio fase. Por otro lado se presenta un generador basado en mapeos multi-modales el cual obtiene una secuencia binaria por medio de la combinación de diferentes modas, la principal ventaja radica en que solo es necesario definir un mapeo para obtener diferentes comportamientos, de igual forma este generador presenta resultados satisfactorios al ser evaluado por las pruebas estadísticas propuestas por el NIST.""The security of digital information is increasingly due to increasing use of mobile devices, in addition to the increase in transactions conducted via Internet. This represents a great challenge in order to achieve confidentiality, integrity and authentication is necessary use specialized mechanisms, a way of providing these services is through cryptography, however, the growing demand requires new algorithms that are faster and safe. One option to achieve these goals is chaos based cryptography. This thesis is presented in three parts, in the first part the basic concepts and definitions of the cryptography and dynamic systems as well as the tools to study each of these systems are shown. Furthermore an overview of these areas and a classification is given, we will focus on stream ciphers and discrete time dynamical systems. Note that the dynamical systems studied in this work unlike the logistic and tent map are multimodal, which have certain advantages compared with uni-modal maps. Afterwards the similarities and differences found in these two areas are analyzed, resulting in chaotic cryptography, which has been studied by several research groups in recent years. In the second part of this work we construct two pseudo-random generators, which are an essential part in the use of stream ciphers, in one hand we propose use positive and negative values in the bifurcation parameter of the logistic map together with delays, in this way it is possible to build a generator showing satisfactory results to statistical tests of randomness proposed by the NIST and it is not possible to reconstruct the phase space. On the other hand we present a generator based on multi-modal maps which produce a binary sequence obtained by combining different modal, the main advantage is that it is only necessary to define one map for different behaviors, similarly this generator presents satisfactory results when is evaluated by statistical tests proposed by the NIST.
Absence of a significant pharmacokinetic interaction between atorvastatin and fenofibrate: a randomized, crossover, study of a fixed-dose formulation in healthy Mexican subjects
Get PDF"Several clinical trials have substantiated the efficacy of the co-administration of statins like atorvastatin (ATO) and fibrates. Without information currently available about the interaction between the two drugs, a pharmacokinetic study was conducted to investigate the effect when both drugs were co-administered. The purpose of this study was to investigate the pharmacokinetic profile of tablets containing ATO 20 mg, or the combination of ATO 20 mg with fenofibrate (FNO) 160 mg administered to healthy Mexican volunteers. This was a randomized, two-period, two-sequence, crossover study; 36 eligible subjects aged between 2050 years were included. Blood samples were collected up to 96 h after dosing, and pharmacokinetic parameters were obtained by non-compartmental analysis. Adverse events were evaluated based on subject interviews and physical examinations. Area under the concentration-time curve (AUC) and maximum plasma drug concentration (C-max) were measured for ATO as the reference and ATO and FNO as the test product for bioequivalence design. The estimation computed (90% confidence intervals) for ATO and FNO combination versus ATO for C-max, AUC(0-t) and AUC(0-infinity), were 102,09, 125,95, and 120,97%, respectively. These results suggest that ATO and FNO have no relevant clinical-pharmacokinetic drug interaction.
Magnetocaloric properties of rapidly solidified Dy3Co alloy ribbons
Get PDF"The magnetic and magnetocaloric (MC) properties of melt-spun ribbons of the Dy3Co intermetallic compound were investigated. Samples were fabricated in an Ar environment using a homemade melt spinner system at a linear speed of the rotating copper wheel of 40 ms(-1). X-ray diffraction analysis shows that ribbons crystallize into a single-phase with the Fe3C-type orthorhombic crystal structure. The M(T) curve measured at 5mT reveals the occurrence of a transition at 32K from a first to a second antiferromagnetic (AFM) state and an AFM-to-paramagnetic transition at T-N = 43 K. Furthermore, a metamagnetic transition is observed below T-N, but the magnetization change Delta M is well below the one reported for bulk alloys. Below 12 K, large inverse MC effect and hysteresis losses are observed. This behavior is related to the metamagnetic transition. For a magnetic field change of 5 T (2 T) applied along the ribbon length, the produced ribbons show a peak value of the magnetic entropy change Delta S-M(peak) of -6.5 (-2.1) Jkg(-1) K-1 occurring close to TN with a full-width at half-maximum delta T-FWHM of 53 (37) K, and refrigerant capacity RC = 364 (83) Jkg(-1) (estimated from the product vertical bar Delta S-M(peak)vertical bar x delta T-FWHM).
Forced synchronization of autonomous dynamical Boolean networks
Get PDF"We present the design of an autonomous time-delay Boolean network realized with readily available electronic components. Through simulations and experiments that account for the detailed nonlinear response of each circuit element, we demonstrate that a network with five Boolean nodes displays complex behavior. Furthermore, we show that the dynamics of two identical networks display near-instantaneous synchronization to a periodic state when forced by a common periodic Boolean signal. A theoretical analysis of the network reveals the conditions under which complex behavior is expected in an individual network and the occurrence of synchronization in the forced networks. This research will enable future experiments on autonomous time-delay networks using readily available electronic components with dynamics on a slow enough time-scale so that inexpensive data collection systems can faithfully record the dynamics.
Magnetocaloric material based on NdPrFe17 with improved properties
No full text"La presente invención está relacionada con un material magnetocalórico basado en cintas recién solidificadas de NdPrFe17 obtenidas por temple rotatorio. Este material tiene propiedades mejoradas en comparación con otros materiales magnetocalóricos (MC) similares, ya que posee una capacidad de refrigeración mejorada en el rango de la temperatura ambiente debido al ensanchamiento en la curva de variación de entropía magnética en función de la temperatura. Este material es útil como refrigerante magnético como parte de refrigeradores magnetocalóricos.""The instant invention relates to a magnetocaloric material based on NdPrFe17 melt-spun ribbons. This material has improved properties when compared with other similar magnetocaloric (MC) materials since it has an enhanced refrigeration capacity in the room temperature range due to its broader magnetic entropy change as function of the temperature curve. This material is useful as magnetic refrigerant as a part of magnetocaloric refrigerators.
Overexpression of AtGRDP2, a novel glycine-rich domain protein, accelerates plant growth and improves stress tolerance
Get PDF"Proteins with glycine-rich signatures have been reported in a wide variety of organisms including plants, mammalians, fungi, and bacteria. Plant glycine-rich protein genes exhibit developmental and tissue-specific expression patterns. Herein, we present the characterization of the AtGRDP2 gene using Arabidopsis null and knockdown mutants and, Arabidopsis and lettuce over-expression lines. AtGRDP2 encodes a short glycine-rich domain protein, containing a DUF1399 domain and a putative RNA recognition motif (RRM). AtGRDP2 transcript is mainly expressed in Arabidopsis floral organs, and its deregulation in Arabidopsis Atgrdp2 mutants and 35S::AtGRDP2 over-expression lines produces alterations in development. The 35S::AtGRDP2 over-expression lines grow faster than the WT, while the Atgrdp2 mutants have a delay in growth and development. The over-expression lines accumulate higher levels of indole-3-acetic acid and, have alterations in the expression pattern of ARF6, ARF8, and miR167 regulators of floral development and auxin signaling. Under salt stress conditions, 35S::AtGRDP2 over-expression lines displayed higher tolerance and increased expression of stress marker genes. Likewise, transgenic lettuce plants over-expressing the AtGRDP2 gene manifest increased growth rate and early flowering time. Our data reveal an important role for AtGRDP2 in Arabidopsis development and stress response, and suggest a connection between AtGRDP2 and auxin signaling.
Presence of exotic birds in San Luis Potosi city, Mexican Plateau
Get PDF"Se presenta el registro de 12 especies de aves exóticas para la ciudad de San Luis Potosí, México y áreas adyacentes. Los datos presentados se obtuvieron durante durante el periodo agosto de 2012 a agosto de 2013. Del total de especies registradas ocho son confirmaciones (Anas platyrhynchos domesticus, Cairina moschata, Bubulcus ibis, Columba livia, Sturnus vulgaris, Turdus rufopalliatus, Quiscalus mexicanus y Passer domesticus) y cuatro son nuevos registros (Aratinga canicularis, Amazona oratrix, A. autumnalis y Cyanocorax yncas). Aunque no todas las especies exóticas pueden representar un riesgo, debido a que no existen los recursos necesarios para el establecimiento de poblaciones abundantes viables, es importante dar a conocer su estatus en la región. Por lo que, el conocimiento de la presencia de especies exóticas es importante para dar seguimiento a su establecimiento y colonización en una nueva área, para así definir programas de manejo, control y erradicación para estas especies, aunado a programas de educación ambiental que conlleven a un mejor entendimiento sobre los impactos que estas pueden ocasionar.""We recorded 12 exotic bird species in San Luis Potosi, Mexico and adjacent areas. Obtained data were collected during the period August 2012 to August 2013. From the total of recorded species, eight are confirmations (Anas platyrhynchos domesticus, Cairina moschata, Bubulcus ibis, Columba livia, Sturnus vulgaris, Turdus rufopalliatus, Quiscalus mexicanus and Passer domesticus) and four are new records (Aratinga canicularis, Amazona oratrix, A. autumnalis and Cyanocorax yncas). Although not all exotic species represent a risk because of the lack of the necessary resources for the establishment of abundant viable populations, it is important to publicize their status in the region. Therefore, knowing the presence of exotic species in a new distribution area is important for monitoring its establishment and colonization, and defining management, control and eradication programs of these species, along with environmental education programs that would lead to a better understanding of impacts that these species can cause.
Análisis funcional de los promotores Rep y CP de un mutante natural del Virus del rizado foliar amarillo del tomate (TYLCV) y un begomovirus co-infectante
Get PDF"En el 2011, una variante del begomovirus invasor Tomato yellow leaf curl virus-Israel (TYLCV-IL) se aisló de dos plantas colectadas en la Huasteca Potosina: una de Solanum pimpinellifolium coinfectada con el begomovirus nativo ToChLPV; y otra de Solanum lycopersicum coinfectada con el begomovirus, ToSLCV. Ésta variante, denominada TYLCV-IL [SLP], difiere de otras descritas a la fecha por dos alteraciones en la región intergénica del genoma: una deleción de 29 pb corriente arriba del elemento “tallo-asa” conservado, y la duplicación de un segmento de 42 pb corriente abajo del mismo elemento. Estas mutaciones podrían haber alterado las propiedades funcionales de los promotores divergentes y, eventualmente, las características patogénicas de TYLCV-IL. En el presente trabajo analizamos funcionalmente los promotores de los genes que codifican las proteínas Rep y CP de TYLCV-IL [SLP] y la variante no mutada TYLCV-IL [Sin]. Para esto se fusionaron los promotores virales al gen reportero GUS y se analizaron por medio de ensayos de expresión transitoria en protoplastos de tabaco. Los resultados experimentales revelaron que la actividad del promotor Rep de TYLCV-IL [SLP] es muy débil, más de 15 veces menor que la del promotor homólogo de TYLCV-IL [Sin]. La actividad de este último fue 6 veces mayor a la del promotor 35S de CaMV utilizado como control. En contraste, los promotores CP de las dos variantes de TYLCV-IL no mostraron diferencias significativas en su actividad. Un hallazgo adicional fue que el promotor Rep del virus co-infectante ToChLPV exhibe una actividad muy superior a la de TYLCV-IL [Sin] y otros begomovirus, por lo que tiene un potencial biotecnológico importante. La capacidad infectiva de TYLCV-IL [SLP] en ausencia de los begomovirus coinfectantes, se evaluó inoculando por agroinfiltración plantas de N. benthamiana. Todas las plantas desarrollaron síntomas y el genoma viral fue detectado por PCR en los tejidos jóvenes.""In 2011, a variant of the invader begomovirus Tomato yellow leaf curl virus Israel (TYLCV-IL) was isolated from two plants collected in the Huasteca: one of Solanum pimpinellifolium coinfected with native begomovirus ToChLPV; and other Solanum lycopersicum coinfected with begomovirus, ToSLCV. This variant, designated TYLCV-IL [SLP], differs from others described to date for two changes in the intergenic region of the genome: a deletion of 29 bp upstream of the conserved “stem-loop" element and duplication of a segment 42 bp downstream of the same element. These mutations may have altered the functional properties of the divergent promoters and eventually the pathogenic characteristics of TYLCVIL. In the present work we functionally analyze the promoters of the genes encoding Rep and CP proteins of TYLCV-IL [SLP] and the unmutated variant TYLCV-IL [SIN]. To this the viral promoters were fused to the GUS reporter gene and analyzed by transient expression assays in tobacco protoplasts. To this the viral promoters were fused to the GUS reporter gene and analyzed by transient expression assays in protoplasts snuff. The experimental results revealed that the promoter activity of Rep TYLCV-IL [SLP] is too weak, more than 15 times lower than the homologous TYLCV-IL promoter [SIN]. The Activity of the latter was 6 times higher than the CaMV 35S promoter used as a control. In contrast, the CP promoters of the two variants of TYLCV-IL showed no significant difference in their activity. An additional finding was that the Rep promoter of the co-infecting virus, ToChLPV exhibits a much higher activity than TYLCV-IL [Sin] and other begomoviruses, Therefore it has an important biotechnological potential. The infectivity of TYLCV-IL [SLP] in the absence of the co-infecting begomoviruses, was evaluated inoculating N. benthamiana plants by agroinfiltration. All the plants developed symptoms and viral genome was detected by PCR in young tissues.