Comments On The Reforms To The Mexican Energy Laws Of 2008

A strong discussion has taken place in Mexico since the beginning of this millennium concerning the legal reform of the energy sector, particularly the Mexican government\u27s oil company, Petr6leos Mexicanos (Pemex)

Explaining Nonlinearities in Black Hole Ringdowns from Symmetries

It has been recently pointed out that nonlinear effects are necessary to model the ringdown stage of the gravitational waveform produced by the merger of two black holes giving rise to a remnant Kerr black hole. We show that this nonlinear behaviour is explained, both on the qualitative and quantitative level, by near-horizon symmetries of the Kerr black hole within the Kerr/CFT correspondence.Comment: 5 page

Regulation of Monocyte-Macrophage Responses in Cirrhosis—Role of Innate Immune Programming and Checkpoint Receptors

Many aspects of the innate immune system have been studied in cirrhosis, and abnormalities have been described supporting both a pro-inflammatory and anti-inflammatory phenotype of myeloid cells. However, the findings of these studies vary by stage of disease and methodology. The recent description of the syndrome of acute-on-chronic liver failure (ACLF) has refined our understanding of the natural history of cirrhosis. In this context, we review the regulatory mechanisms at play that contribute to the immune abnormalities described in advanced liver disease. Specifically, we review the evidence for epigenetic mechanisms regulating monocyte phenotype, and the role of checkpoint receptors on regulating innate and adaptive immune cell function

Decomposition and factorisation of transients in Functional Graphs

Functional graphs (FGs) model the graph structures used to analyze the behavior of functions from a discrete set to itself. In turn, such functions are used to study real complex phenomena evolving in time. As the systems involved can be quite large, it is interesting to decompose and factorize them into several subgraphs acting together. Polynomial equations over functional graphs provide a formal way to represent this decomposition and factorization mechanism, and solving them validates or invalidates hypotheses on their decomposability. The current solution method breaks down a single equation into a series of \emph{basic} equations of the form $A\times X=B$ (with $A$, $X$, and $B$ being FGs) to identify the possible solutions. However, it is able to consider just FGs made of cycles only. This work proposes an algorithm for solving these basic equations for general connected FGs. By exploiting a connection with the cancellation problem, we prove that the upper bound to the number of solutions is closely related to the size of the cycle in the coefficient $A$ of the equation. The cancellation problem is also involved in the main algorithms provided by the paper. We introduce a polynomial-time semi-decision algorithm able to provide constraints that a potential solution will have to satisfy if it exists. Then, exploiting the ideas introduced in the first algorithm, we introduce a second exponential-time algorithm capable of finding all solutions by integrating several `hacks' that try to keep the exponential as tight as possible

Creencias ecológico-ambientales en la infancia : estudio transcultural

Aquest article aborda les creences que es construeixen en la infància sobre algunes qüestions ecologicoambientals, concretament les que tenen a veure amb les formes de vida i el seu manteniment. Demanem a infants escolaritzats de 9 i 11 anys -colombians, espanyols i anglesos- que s'imaginin una illa deserta on aniran a viure, ja que el coneixement de les seves possibilitats en enfrontar-se amb aquest medi desconegut, amb tots els recursos de què vulguin disposar, proporcionarà una bona oportunitat per determinar si l'educació ecologicoambiental que reben segueix directrius no depredadores. Analitzades les respostes del que s'endurien i farien a l'illa, hem trobat una concepció etnocèntrica ingènua d'acord amb el desenvolupament tecnològic de la cultura occidental.This paper addresses the beliefs constructed in childhood about some ecological-environmental issues, in particular those related to lifestyle and the conception of the needs linked to keeping these. We asked some 9 and 11 year-old Colombian, Spanish and English school children to imagine a desert island in which they were supposed to go to live. This knowledge about their possibilities/abilities when facing an unknown medium, and using all kind of resources they choose to have, will provide a good opportunity to determine if the ecological-environmental education they receive follows the no depredation guidelines. After analysing the responses on what they would take and what would they do in the island, we have found a naïve ethnocentric conception following the technological developments of Western culture.Este artículo aborda las creencias que se construyen en la infancia acerca de algunas cuestiones ecológico-ambientales, concretamente las que tienen que ver con las formas de vida y su mantenimiento. Pedimos a niños/as escolarizados/as de 9 y 11 años -colombianos, españoles e ingleses- que imaginen una isla desierta donde van a vivir, ya que el conocimiento de sus posibilidades al enfrentarse a este medio desconocido, con todos los recursos de los que deseen disponer, proporcionará una buena oportunidad para determinar si la educación ecológico-ambiental que reciben sigue directrices no depredadoras. Analizadas las respuestas de lo que llevarían y harían en la isla, hemos encontrado una concepción etnocéntrica ingénua, acorde al desarrollo tecnológico de la cultura occidental

Modèle elliptique pour la section du filé. 1er partie: la prédiction et l'ajustage d'un modèle elliptique pour filés conventionnels à anneaux en coton (RS)

Uno de los parámetros fundamentales para el estudio de la geometría del tejido es el “diámetro” del hilado. A primera vista puede parecer que el hilado tiene una sección circular, pero en realidad no es así, tiene una sección aproximadamente elíptica. Esta aproximación a la elipse requiere una medición del diámetro mayor y menor (D y d); estas mediciones son difíciles, por lo que se hace necesario encontrar un nuevo método para solucionar este problema. El presente estudio consiste en diseñar un modelo matemático para calcular los diámetros (D y d) de la sección elíptica del hilado convencional de algodón, una nueva metodología para la determinación del perímetro de la sección de los hilados y ajuste a la forma elíptica a la que más se aproxima. Como resultados las secciones de los hilados son elipses con una cierta deformación; las ecuaciones deducidas son muy simples (D = K1 √tex, d = K2 √tex) y tienen una alta correlación y simulación con los diámetros reales.One of the main dimensions requisite in the study of fabric geometry is the “diameter” of yarn, a first assumption being that a yarn has a circular cross-section, but in fact the shape of the yarn crosssection can best be approximated as ellipses. This approximation requires the estimation of the major and minor diameters (D, d); these estimations are difficult (according to various studies) therefore it is necessary to find a new approach to solve this problem. In the present research work it has been carried out a mathematical prediction study for calculate the diameters (D, d) of the ellipses of cotton cross-section yarns, and a new methodology for determination the cross-section profile and ellipses fitting. As a result the cross-sections of the yarns are ellipses with some deformation; the equations deduced are very simple (D = K1 √tex, d = K2 √tex) and has a high correlation and simulation with actual diameters.Le diamètre du filé est l’un des paramètres essentiels dans l’étude de la géométrie d’un tissu. À première vue, il semblerait que le filé a une section circulaire. Or, ce n’est pas le cas, sa section est presque elliptique. Cette section proche de l’ellipse requiert une mesure des diamètres majeur et mineur (D et d) ; ces mesures étant difficiles, il faut mettre au point une autre méthode pour résoudre le problème. L’étude consiste à établir un modèle mathématique pour calculer les diamètres (D et d) de la section elliptique du filé conventionnel en coton, une nouvelle méthodologie pour détérminer le périmètre de la section des filés et l’ajustage sur la forme elliptique la plus proche. Résultat, les sections des filés sont des ellipses légèrement déformées ; les équations déduites sont très simples (D = K1 √tex, d = K2 √tex) et elles ont une corrélation et une simulation importantes par rapport aux diamètres réels

Erythropoietin as a protective factor in rat CNS cells receiving radiotherapy: An in vitro study

Objetivo. Investigar el efecto de la eritropoyetina en cultivos celulares de corteza cerebral de ratas cuando se administra radioterapia. Materiales y métodos. El estudio se desarrolla con la obtención de corteza cerebral de embriones de 17 días de preñez de ratas Wistar. Las células cultivadas después de 72 horas de la extracción de la corteza se dividieron en dos grupos, a uno de ellos se le administró eritropoyetina alfa a una concentración de 30 pM y el otro era el grupo control. A los dos grupos de células se les radió con 6 Gy mediante un aparato Phoenix. Tras la radioterapia permanecieron 24 horas en la incubadora antes de fijarlas. Las células fueron fijadas con formaldehído al 4%. A continuación, con la técnica de TUNEL, se valoró el número de células apoptóticas en los cultivos radiados. Resultados. Se observó un porcentaje de apoptosis del 25,22% del grupo de cultivo sin eritropoyetina, mientras que en el grupo de células radiadas con eritropoyetina fue del 15,5%. Las variables cuantitativas se analizaron mediante el test t de Student y el resultado de la comparación entre los dos grupos fue estadísticamente significativo (p < 0,0001). Conclusión. En nuestro modelo experimental in vitro se comprobó que la eritropoyetina es eficaz en la prevención de la apoptosis en células del sistema nervioso central de ratas por radiación. Esto abre nuevos campos para la investigación del efecto protector del sistema nerviosoAim. To investigate the effect of erythropoietin in cultured rat cerebral cortex cells receiving radiotherapy. Materials and methods. Cerebral cortex was taken from 17-day-old Wistar rat embryos and placed in culture. At 72 hours, the cultures were divided into two groups, one receiving 30 pM erythropoietin alpha and the other was the control group. Both groups received 6 Gy from a Phoenix apparatus and were incubated for another 24 hours before fixation in 4% formaldehyde. TUNEL technique was employed to calculate the number of apoptotic cells in the irradiated cultures. 206 www.neurologia.com Rev Neurol 2014; 58 (5): 199-206 A. Gómez-De la Riva, et al Results. Apoptosis affected 25.22% of the cells cultured without erythropoietin and 15.5% in the group receiving erithropoyetin. Student’s t-test was used to analyse quantitative variables and showed a significant difference in apoptosis between the two groups (p < 0.0001). Conclusion. Our in vitro experimental model demonstrated that erythropoietin effectively prevents apoptosis in irradiated rat SNC cells, opening new fields for investigation into protective agents for the nervous syste

Comentarios Sobre Las Reformas Del Ano 2008 Al Sector Energetico Mexicano

Desde inicios del milenio, en Mxico se vivi6 una fuerte discusi6n sobre la reforma legal del sector energ6tico; en particular en torno a Petr6leos Mexicanos (Pemex)

A comparison of open-source LiDAR filtering algorithms in a mediterranean forest environment

Light detection and ranging (LiDAR) is an emerging remote-sensing technology with potential to assist in mapping, monitoring, and assessment of forest resources. Despite a growing body of peer-reviewed literature documenting the filtering methods of LiDAR data, there seems to be little information about qualitative and quantitative assessment of filtering methods to select the most appropriate to create digital elevation models with the final objective of normalizing the point cloud in forestry applications. Furthermore, most algorithms are proprietary and have high purchase costs, while a few are openly available and supported by published results. This paper compares the accuracy of seven discrete return LiDAR filtering methods, implemented in nonproprietary tools and software in classification of the point clouds provided by the Spanish National Plan for Aerial Orthophotography (PNOA). Two test sites in moderate to steep slopes and various land cover types were selected. The classification accuracy of each algorithm was assessed using 424 points classified by hand and located in different terrain slopes, cover types, point cloud densities, and scan angles. MCC filter presented the best overall performance with an 83.3% of success rate and a Kappa index of 0.67. Compared to other filters, MCC and LAStools balanced quite well the error rates. Sprouted scrub with abandoned logs, stumps, and woody debris and terrain slopes over 15° were the most problematic cover types in filtering. However, the influence of point density and scan-angle variables in filtering is lower, as morphological methods are less sensitive to them

El fenómeno de las viviendas desocupadas

Trabajo realizado mediante encargo del Ministerio de Vivienda a través de la Fundación General de la Universidad Autónoma de Madri