On the Discretization of a Class of Homogeneous Differentiators

This paper proposes explicit and implicit discrete-time realizations for a class of homogeneous sliding-mode-based differentiators. The proposed approach relies on the exact discretization of the continuous differentiator. Also, it is demonstrated that the proposed implicit discretization always exists, is non-anticipative and unique. A numerical simulation shows the better performance of the implicit scheme over the proposed and the referenced explicit implementations.ITESO, A.C

Discretization of the Robust Exact Filtering Differentiator Based on the Matching Approach

This paper presents a time discretization of the robust exact filtering differentiator, a sliding mode differentiator coupled to filter, which provides a suitable approximation of the derivatives for some noisy signals. This realization rely on the stabilization of a pseudo linear discrete-time system, it is attained through the matching approach. As in the original case, the convergence of the robust exact filtering differentiator depends on the bound of a higher-order derivative. Nevertheless, this new realization can be implemented with or without the knowledge of such constant. It is demonstrated that the system trajectories converge to a neighborhood of the origin for a free-noise input. Finally, comparisons between the behavior of the differentiator with different design parameters are presented.ITESO, A.C

Regulation of BDNF Release by ARMS/Kidins220 through Modulation of Synaptotagmin-IV Levels

BDNF is a growth factor with important roles in the nervous system in both physiological and pathological conditions, but the mechanisms controlling its secretion are not completely understood. Here, we show that ARMS/Kidins220 negatively regulates BDNF secretion in neurons from the CNS and PNS. Downregulation of the ARMS/Kidins220 protein in the adult mouse brain increases regulated BDNF secretion, leading to its accumulation in the striatum. Interestingly, two mouse models of Huntington's disease (HD) showed increased levels of ARMS/Kidins220 in the hippocampus and regulated BDNF secretion deficits. Importantly, reduction of ARMS/Kidins220 in hippocampal slices from HD mice reversed the impaired regulated BDNF release. Moreover, there are increased levels of ARMS/Kidins220 in the hippocampus and PFC of patients with HD. ARMS/Kidins220 regulates Synaptotagmin-IV levels, which has been previously observed to modulate BDNF secretion. These data indicate that ARMS/Kidins220 controls the regulated secretion of BDNF and might play a crucial role in the pathogenesis of HD.SIGNIFICANCE STATEMENT BDNF is an important growth factor that plays a fundamental role in the correct functioning of the CNS. The secretion of BDNF must be properly controlled to exert its functions, but the proteins regulating its release are not completely known. Using neuronal cultures and a new conditional mouse to modulate ARMS/Kidins220 protein, we report that ARMS/Kidins220 negatively regulates BDNF secretion. Moreover, ARMS/Kidins220 is overexpressed in two mouse models of Huntington's disease (HD), causing an impaired regulation of BDNF secretion. Furthermore, ARMS/Kidins220 levels are increased in brain samples from HD patients. Future studies should address whether ARMS/Kidins220 has any function on the pathophysiology of HD

Quid: observatorio de medios

Medios de Comunicación y Derecho a la Información en Jalisco, consta de cinco partes: Medios de Comunicación y Estado; Medios Públicos de Jalisco; Medios Electrónicos de la Zona Metropolitana de Guadalajara; Transparencia en el estado; y Sociedad civil y Derecho a la Información. En estas secciones podrán encontrarse diversos artículos que documentan casos como las presuntas transgresiones del gobernador de Jalisco al artículo 134 constitucional (que hace referencia a la prohibición expresa que tienen los gobernantes para hacer promoción personal en medios de comunicación con recursos públicos); las donaciones que el gobierno del estado ha dado a instituciones como Televisa, TV Azteca o MTV; los cambios en el Sistema Jalisciense de Radio y Televisión; el surgimiento de la Asociación Mexicana del Derecho a la Información capítulo Jalisco; entre otros. Estos temas son muy importantes porque son coyunturas que dan pistas de cómo está conformado el sistema de comunicación de nuestro entorno.ITESO, A.C

Nonconventional Wastewater Treatment for the Degradation of Fuel Oxygenated (MTBE, ETBE, and TAME)

Catalytic wet air oxidation (CWAO) is a nonconventional wastewater treatment, consisting of oxygen pressure releasing inside a reactor in order to degrade organic compounds dissolved in water, using a solid catalyst in the presence of an activated O2 species, usually at temperatures ranges of 125–250°C and pressures of 10–50 bar. CWAO can reduce operating costs of conventional treatment due to the use of ideal catalyst that is able to improve reaction conditions at temperatures and pressures as mild as possible, simultaneously setting high catalytic activity and long-term stability of heterogeneous catalysts. Oxygenated fuels are gasoline additives in reformulated gasoline and oxyfuels. In the beginning, they provided an alternative solution of environmental problems, such as greenhouse gas emissions and octane enhancement, caused by fossil fuel use. The oxygenated fuels frequently used are methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). However, there is environmental impact from oxygenated fuel hydrocarbons related to widespread contamination of groundwater and other natural waters. Our research group developed a wide study in order to evaluate several catalysts (Ru, Au, Cu, and Ag supported on Al2O3, Al2O3-CeO2, and TiO2-CeO2) and to obtain the best for the efficiency of the oxidation process

Assessment of prospective geological hazards in Torrevieja-La Mata coast (western Mediterranean) based on Pleistocene and Holocene events

The coastal zone in which the lagoons of La Mata and Torrevieja (Eastern Spain) developed can be described as a compilation of geo-hazards typical of the Mediterranean realm. This study has focused mainly on those linked to recent tectonics. Extensive use of the amino acid racemization dating method allowed us to establish the evolution of all the geomorphological units differentiated in the area, the most striking manifestation being at the La Mata Lagoon Bar, where MIS 5 deposits settled on MIS 7 sediments along a marked erosive unconformity, thereby attesting coastal uplift between these two stages. In addition, recent uplift processes were reflected on stepped abrasion platforms and, in some cases, enormous boulders were transported over these platforms by extreme surge waves. Furthermore, we obtained feasible evidence that, during the end of MIS 5, an earthquake with an offshore epicenter linked to Torrevieja Fault, Bajo Segura Fault or the set of faults linked to the former, was responsible for tsunami surge deposits represented in accumulations of randomly arranged and well-preserved Glycymeris and Acanthocardia shells. Recent catastrophic effects linked to the earthquakes were also detected. In this regard, comparison of the paleontological and taphonomic analyses allowed us to discern between wave and tsunami surge deposits. Therefore, evidence of these hazards undoubtedly points to important future (and present) erosive and/or catastrophic processes, which are enhanced by the presence of tourist resorts and salt-mining industry. Thus, these sites are also threatened by future increases in sea level in the context of warmer episodes, attested by raised marine fossil deposits. At the north of Cervera Cape, beaches will be eroded, without any possibility of sediment input from the starved Segura River delta. At the south of this cape, waves (and tsunamis) will erode the soft rocks that built up the cliff, creating deep basal notches

La cueva de el Sidron (Borines, Piloña, Asturias) : primeros resultados

Se exponen los resultados preliminares de las excavaciones arqueológicas llevadas a cabo en la Cueva de El Sidrón entre 2000 y 2002, de acuerdo con los tres objetivos principales que conciernen al registro fósil humano: las características antropológicas, cómo y cuándo llegaron allí y la relación entre fósiles y cultura. Las primeras conclusiones obtenidas son que los restos humanos pertenecen al Neandertal, que el registro arqueológico corresponde a un tecno-complejo del Paleolítico Medio y que están en posición secundaria.We expose the preliminary results ofthe archaeological excavations developed between 2000-2002 in Sidrón's Cave, according to the three main objectives that concern the human fossil record: the anthropological characteristics, how and when they arrived there and the relation between fossils and culture. We conclude preliminarily that the record belongs to Horno Neanderthalensis, archeological remains to the Middle Paleolithic techno-complex, and they are in a secondary [email protected]

Estudio de indicadores de suelo y planta para la programación del riego en cerezos jóvenes. Póster

En zonas áridas y semiáridas existe una necesidad constante de mejorar la eficiencia del uso del agua. En este sentido, el empleo de indicadores puede convertirse en una herramienta eficaz para confeccionar programas de riego más precisos. Durante el verano de 2018 y 2019, con el objetivo de estudiar la sensibilidad y la variabilidad de distintos indicadores de suelo y planta, se llevó a cabo un ensayo en cerezos jóvenes (Prunus avium L. ‘Lapins’). Tres tratamientos de riego aplicados fueron: con-trol ( CTL) regado para asegurar condiciones no limitantes de agua en el suelo, y dos tratamientos defi-citarios, MS y SS, los cuales fueron regados como CTL hasta finales de junio, momento a partir del cual se alternaron 2 ciclos consecutivos de supresión - reanudación del riego. Los árboles fueron recupera-dos cuando el potencial hídrico de tallo (Ψstem) alcanzó valores durante el primer y segundo ciclo de supresión de -1,3 y -1,7 MPa para MS y -1,6 y -2,3 MPa para SS. Los indicadores de suelo y planta estudiados fueron afectados por el déficit hídrico impuesto. La tasa de crecimiento diaria del tronco (TGR) y la máxima contracción diaria del tronco (MDS) mostraron una respuesta rápida al cambio de riego; sin embargo, ambos indicadores tuvieron una alta variabilidad. En este sentido, MDS mostró la mayor intensidad de señal, aunque la sensibilidad de este indicador fue mitigada por su coeficiente de variación (CV). Por otro lado, el contenido volumétrico de agua del suelo (θv) y la temperatura de la copa (Tc) exhibieron una alta sensibilidad debido a la baja variabilidad. Ψstem, indicador usado como referencia, mostró una estrecha relación con el resto de los indicadores estudiados, excepto con TGR. La relación observada entre MDS y Ψstem fue lineal hasta alcanzar valores de Ψstem de -1,3 MPa. Los resultados obtenidos sugieren que Ψstem es un indicador sensible al estrés con un bajo CV; Tc, la dife-rencia de temperatura de la copa y del aire y el índice de estrés del cultivo pueden ayudar a determinar, de forma rápida y sencilla, el estado hídrico del cultivo; y MDS podrías ser utilizado hasta valores de estrés moderados para la elaboración de programas de riego en cerezos jóvenes

Social interactions and business portfolio among vegetable produc-ers in central Mexico

Objective: Analyze social interactions and business portfolio of vegetable producers in Central Mexico. Design/methodology/approach: we worked with 16 small vegetable producers. Semi-structured questionnaires and periodic monitoring were used in field to collect data. A Social Network analysis was carried out to know social interactions between producers, and the Boston Consulting Group (BCG) and Ansoff matrix for the business portfolio. Results: We found that the products with potential in the market were lettuce and nopal. Broccoli and squash represent low sales and low utility. Producers with a higher degree of centrality grow lettuce, broccoli and squash, so we suggested to develop strategies for introducing nopal. Limitations on study/implications: It was necessary to deep in market and consumers analysis.Objective: To analyze the social interactions and business portfolio of vegetable producers in central Mexico. Design/methodology/approach: Work was conducted with 16 small-scale vegetable producers. Semi-structured questionnaires and periodic monitoring were used in the field to collect data. A Social Network analysis was carried out to understand the social interactions between producers, and the Boston Consulting Group (BCG) and Ansoff matrix was used for the business portfolio. Results: The study found that the products with potential in the market were lettuce and nopal. Broccoli and squash represent low sales and low utility. Producers with a higher degree of centrality grow lettuce, broccoli and squash, so we suggested developing strategies for introducing nopal. Limitations on study/implications: It was necessary to delve into market and consumers analysis