Síntesis asistida por ultrasonido de Pirazolo[3,4-b]Piridinas policíclicas fusionadas

This work describes a synthetic methodology developed to obtain fused polycyclic pyrazolo[3,4-b]pyridines. The synthesis was carried out in two stages, starting with the preparation of α,β-unsaturated naphthones and their subsequent cyclocondensation with 5-amino-1-phenyl-3-methyl-1H-pyrazole. The advantages of this approach include simplicity, atomic efficiency, selectivity, and good yields with minimal environmental impact. The synthetic route is aimed at obtaining N-heterocycles with specific points of structural diversification that are of interest for later exploration of their biological properties.Este trabajo describe una metodología sintética desarrollada para la obtención de pirazolo[3,4-b]piridinas policíclicas fusionadas. La síntesis se llevó a cabo en dos etapas, iniciando con la obtención de naftonas α,β-insaturadas y su posterior ciclocondensación con 5-amino-1-fenil-3-metil-1H-pirazol. Las ventajas de este enfoque incluyen simplicidad, eficiencia atómica, selectividad y buen rendimiento con un mínimo impacto ambiental. La ruta sintética está orientada hacia la obtención de N-heterociclos con puntos específicos de diversificación estructural que sean interés para la posterior exploración de sus propiedades biológicas

Characteristics of specific reading disability in children from a neuropsychological clinic in Mexico City

Objective. This report describes the main clinical features associated with specific reading disability (RD) in a group of 778 school-age children studied in a Neuropsychological Clinic in Mexico City. Material and Methods. The study was performed retrospectively, using data abstracted from clinical records of subjects seen in 1995-1996. Children were mainly from low and middle economic strata and aged between 6 to 12 years. The following data were collected: age, gender, diagnosis, school grade, food intake, maternal complications during pregnancy, perinatal and postnatal neurological risk factors, and neurological signs and handedness. Results. Subjects with RD had a mean age of 102.9 months, were predominantly male (male female ratio, 2:1). Among the study group, 49.1% of the children were diagnosed with RD of a visuo-sensory-motor type, and 75.1% were from early school years (1st to 3rd grades); 27.6% showed evidence of malnutrition. A previous history of language disorders (49.2%), and a high frequency of perinatal risk factors and neurological soft signs were also found. Conclusions. This study shows that variables such as gender, food intake, and genetic and neurological risk factors, were associated with reading disabilities in school children

Ciclo de videoconferencias “Desafíos y prospectiva de la Industria de las Tecnologías para la Información, Comunicación y Conocimiento" Retos de Innovación para los servicios de gobierno: el caso de las telecomunicaciones en México.

El Ciclo de videoconferencias “Desafíos y prospectiva de la Industria de las Tecnologías para la Información, Comunicación y Conocimiento”es una iniciativa de la Red de Investigación en Cómputo del IPN (RIC), la Academia de Ingeniería de México y el Consorcio de Universidades para el Desarrollo del Internet (CUDI), La Academia Mexicana de Informática (AMIAC) y la Universidad de Guadalajara (UdG) que se desarrolla en el formato de conferencias y páneles de expertos de diferentes sectores de la industria de las TICC, quienes presentan su perspectiva sobre el tema central del ciclo para cada año, debatiendo aspectos que resultan críticos para comprender e incidir en dicha industria.Con esta iniciativa, los organizadores pretenden abrir una ventana hacia la industria de las TICC, para que las comunidades pertenecientes a este sector faciliten su inserción y activismo en torno a las temáticas planteadas.13_08_21_ticc.wm

Sound localization and word discrimination in reverberant environment in children with developmental dyslexia

Objective Compare if localization of sounds and words discrimination in reverberant environment is different between children with dyslexia and controls. Method We studied 30 children with dyslexia and 30 controls. Sound and word localization and discrimination was studied in five angles from left to right auditory fields (-90o, -45o, 0o, +45o, +90o), under reverberant and no-reverberant conditions; correct answers were compared. Results Spatial location of words in no-reverberant test was deficient in children with dyslexia at 0º and +90o. Spatial location for reverberant test was altered in children with dyslexia at all angles, except -90o. Word discrimination in no-reverberant test in children with dyslexia had a poor performance at left angles. In reverberant test, children with dyslexia exhibited deficiencies at -45o, -90o, and +45o angles. Conclusion Children with dyslexia could had problems when have to locate sound, and discriminate words in extreme locations of the horizontal plane in classrooms with reverberation

Demographic Drivers of Aboveground Biomass Dynamics During Secondary Succession in Neotropical Dry and Wet Forests

The magnitude of the carbon sink in second-growth forests is expected to vary with successional biomass dynamics resulting from tree growth, recruitment, and mortality, and with the effects of climate on these dynamics. We compare aboveground biomass dynamics of dry and wet Neotropical forests, based on monitoring data gathered over 3–16 years in forests covering the first 25 years of succession. We estimated standing biomass, annual biomass change, and contributions of tree growth, recruitment, and mortality. We also evaluated tree species’ contributions to biomass dynamics. Absolute rates of biomass change were lower in dry forests, 2.3 and 1.9 Mg ha−1 y−1, after 5–15 and 15–25 years after abandonment, respectively, than in wet forests, with 4.7 and 6.1 Mg ha−1 y−1, in the same age classes. Biomass change was largely driven by tree growth, accounting for at least 48% of biomass change across forest types and age classes. Mortality also contributed strongly to biomass change in wet forests of 5–15 years, whereas its contribution became important later in succession in dry forests. Biomass dynamics tended to be dominated by fewer species in early-successional dry than wet forests, but dominance was strong in both forest types. Overall, our results indicate that biomass dynamics during succession are faster in Neotropical wet than dry forests, with high tree mortality earlier in succession in the wet forests. Long-term monitoring of second-growth tropical forest plots is crucial for improving estimates of annual biomass change, and for enhancing understanding of the underlying mechanisms and demographic drivers.</p