543 research outputs found
Visión del evaluador sobre el proceso de evaluación docente
Trabajo presentado en: Jornada de Formación sobre la Evaluación de la Actividad Docente del Profesorado (DOCENTIA), Burgos, 22 de mayo de 2009. Programa Docenti
Ulva Genus as Alternative Crop: Nutritional and Functional Properties
Use of seaweed by humans is an ancient practice. In Asian countries, the use of them in human and animal feed, traditional medicine, and compost in agriculture is well documented. Since the twenty-first century begins, the scientific interest for seaweed had increased in Occidental countries. Ulva or Enteromorpha is a green macroalgae genus that raises and cultivates around the world. It has salinity tolerance and growth with diverse nitrogen ratios, be able to farm them in aquaculture systems. Scientific studies seen in this genus an interesting profile of chemical compounds: The protein is similar in quantity and quality to soy or some animal products; dietetic fiber percentage is elevated (>40%), being around 40% soluble fiber of them. In addition, fiber fraction presents Ulvan, a complex sulfated polysaccharide that presents antiviral, antihyperlipidemic, and antidiabetic effect in animal assays. Moreover, antioxidant and phytochemical profile has not being totally elucidated, giving important opportunities to scientific community for explode consciously this biological resource
On the development of a MODEM for data transmission and control of electrical household appliances using the low-voltage power-line
This paper presents a CMOS 0,6μm mixed-signal MODEM ASIC for data transmission on the low-voltage power line. The circuit includes all the analog circuitry needed for input interfacing and modulation/demodulation (PLL-based frequency synthesis, slave filter banks with PLL master VCO for tuning, decision circuitry, etc.) plus the logic circuitry needed for control purposes. The circuit operates correctly in the whole industrial temperature range, from -45 to 80°C, under 5% variations of the 3.3V supply voltage.Comisión Interministerial de Ciencia y Tecnología FD97-1611(TIC)Ministerio de Ciencia y Tecnología TIC200 1-092
CMOS mixed-signal MODEM for data transmission and control of electrical household appliances using the low-voltage power-line
This paper presents a CMOS 0.6μm mixed-signal MODEM ASIC for data transmission using the low-voltage power line. This circuit includes all the analog blocks needed for input interfacing and modulation/demodulation (PLL-based frequency synthesis, slave filter banks with PLL master VCO for tuning, and decision circuitry) plus the logic circuitry needed for control purposes. The circuit operates correctly within the industrial temperature range, from -45 to 80°C, under 5% variations of the 3.3V supply voltage.Comisión Interministerial de Ciencia y Tecnología 1FD97-1611(TIC)Ministerio de Ciencia y Tecnología TIC2001-092
Procesos de Investigación Acción en un programa de formación de docentes de lengua extranjera : voces desde dentro
ABSTRACT: In this article, we report the final results of a multiple case study that brought together the experiences and reflections of student teachers, cooperating teachers, and advisors about the action research process within the framework of the academic practicum in a foreign language teaching program. Through observations, interviews, focus groups, and research report analyses, the researchers recognized the personal, professional, and political dimensions that guide participants' teaching and research actions. Findings shed light on issues such as collaboration and engagement to promote conversations that actually connect life in schools and life at the university, and to support continuous learning for teachers. The insights we gained evidenced that the teachers, students, and administrators in the teaching program and their colleagues in the public schools need to strengthen their links through proposals of experiential learning which promote joint efforts, symmetric relationships, and expertise co-construction; thus, enabling all participants to validate their process as individuals, as members of educational institutions, and as key actors in promoting and sustaining a better society.RESUMEN: Este artículo presenta los resultados finales de un estudio de caso múltiple sobre las experiencias y reflexiones de los practicantes, los profesores cooperadores y los asesores universitarios sobre la investigación acción en el marco de su práctica docente. Por medio de observaciones, entrevistas, grupos focales y análisis de trabajos de grado, los investigadores reconocieron las dimensiones personales, profesionales y políticas que guían las acciones pedagógicas e investigativas de los participantes. Los resultados permiten tener pautas claras sobre asuntos como la colaboración y el compromiso, para mantener una comunicación que conecte realmente la vida en las escuelas con la vida en la universidad, fortaleciendo nuestro aprendizaje continuo como maestros. Los resultados evidencian que los profesores, estudiantes y administradores de la Licenciatura y sus colegas en las escuelas públicas necesitan fortalecer lazos a través de propuestas que promueva esfuerzos conjuntos, relaciones simétricas y co-construcción de experticia, con el fin de validar y reflexionar sobre sus procesos como individuos, como miembros de instituciones educativas y como agentes claves para mantener y promover una mejor sociedad
Caracterización de la actividad amilásica presente en extractos larvarios de dos polillas plagas de la papa: Tecia solanivora y Symmetrischema tangolias
Tecia solanivora and Symmetrischema tangolias (Lepidoptera: Gelechiidae) moths cause serious damage to Solanum tuberosum tubercles. The purpose of this study was to isolate and biochemically characterize amilases present in different larval moth stages. Soluble proteins were extracted from the larval stages raised in the laboratory. Differences in protein concentration were determined by spectrophotometry. Average weight for each larvae was calculated. T. solanivora was heavier and more soluble protein was extracted as compared with S. tangolias. Amilase activity of the different protein extracts was identified using starch degradation techniques. The amylasic activity of the IV stage of T. solanivora and S. tangolias incubated at different intervals of time were found to react different, however the results became similar when the activity of both extracts was scored after 72 h time reaction. Eleven protein bands between 225 and 10 kDa were identified electrophoretically. Among these bands, amylases were identified in both species in the 4 different stages in accordance to the molecular weights equivalent to 50 kDa. The protein bands of this enzyme were more defined in the I and II than in the III and IV stages, where they appeared quite diffused. Amylase activity was not linked to soluble protein concentrations; instead, it depended on reaction conditions. These results suggest the possibility of designing new forms of biocontrol against potato mothsLas polillas Tecia solanivora y Symmetrischema tangolias (Lepidoptera: Gelechiidae) ocasionan daños significativos a los tubérculos de Solanum tuberosum. El objetivo de este estudio fue aislar y caracterizar bioquímicamente las amilasas presentes en los diferentes estadios larvales de estas polillas. Para efectos comparativos se extrajo las proteínas solubles de estadios larvales criados en el laboratorio para determinar espectrofotométricamente diferencias en la concentración de cada extracto. Se calculó el peso promedio de cada larva: T. solanivora resultó ser más pesada y de ella se obtuvo más proteína soluble en comparación con S. tangolias. La actividad amilásica en los extractos proteicos fue identificada mediante degradación de almidones. Extractos de los estadios IV de ambas polillas, incubados a diferentes intervalos de tiempo, presentaron actividades amilásicas diferentes, aunque resultaron bastante similares cuando se leyeron los resultados de cada extracto tarde a las 72 h. Mediante electroforesis de los extractos proteicos de las larvas de las dos especies, migraron alrededor de 11 bandas proteicas entre 225 y 10 kDa. Entre estas bandas, las amilasas fueron reconocidas en ambas especies y en los 4 estadios como bandas de 50 kDa. La(s) banda(s) probablemente isofórmicas de esta enzima aparecieron muy definidas en los estadios I y II, en contraste con las formas difusas encontradas en los estadios III y IV. La actividad amilásica no estuvo ligada a las concentraciones proteicas sino a las condiciones de reacción. El estudio sugiere la posibilidad de diseñar formas inéditas de biocontrol contra estas plagas
Aggregation induced emission of a new naphthyridine-ethynyl-gold(I) complex as a potential tool for sensing guanosine nucleotides in aqueous media
A new organometallic alkynyl-gold(I) complex, capable of exhibiting Aggregation Induced Emission was designed and synthesized. The linear complex structure possesses a central Au(I) atom, bearing two axial ligands: (1) 1,3,5-Triaza-7-phosphaadamantane; and (2) 2- acetamido-7-ethynyl-1,8-naphthyridine. While the former accounts for its partial solubility in aqueous environment, the latter acts as a receptor unit for binding guanosine nucleotides and derivatives via multiple hydrogen bonding. At high concentrations, aggregation of the complex was observed by the formation of new absorption (λmax ~ 400 nm) and emission bands (550-700 nm). Formation of aggregates of ca. 60 nm diameter was confirmed with Small Angle X-Ray Scattering (SAXS). Disruption of the aggregates in the presence of guanosine derivatives resulted in a ratiometric signal with apparent association constants in the order of 105 M-1 and high sensitivity (around 63% signal change) which are, to the best of our knowledge, in line with the highest recorded for nucleotide sensing based on hydrogen bonding that are capable of working in water. Computational studies indicate the presence of additional hydrogen bonding interactions that account for the strong binding of the Au(I) complex to phosphorylated Guanosine nucleotides
Influence of ships emissions in the ultrafine particles pollution in an urban coastal air
Comunicación presentada en: V Reunión Española de Ciencia y Tecnología de Aerosoles – RECTA 2011 celebrada del 27 al 29 de junio de 2011 en CIEMAT, Madrid.Experimental data (2008-2009) of particle number (N≥2.5 nm diameter) and black carbon (BC) concen-trations and of gaseous pollutants recorded in the city of Santa Cruz de Tenerife was analyzed in order to asses the impact of ship emissions on the ultrafine particle (UFP) concentrations in coastal urban areas. The observed relationship between N and the other air pollutants, allowed segregating the contribu-tion of vehicle exhaust and of ship emissions to the UFP con-centrations in the urban ambient air.
The influence of fresh vehicle exhaus
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Cold temperature tolerance of the alien Indo-Pacific damselfish Neopomacentrus cyanomos from the Southern Gulf of Mexico
The abundance of the alien, Indo-Pacific damselfish Neopomacentrus cyanomos on an oil-loading platform in the southwest Gulf of Mexico indicates that widely distributed platforms could facilitate the expansion of its geo- graphic range across the western and northern fringes of the Gulf. From there it likely will spread to other areas of the Greater Caribbean. The lionfish example demonstrates that it eventually happens, and can do so rapidly. Reduced temperature effects on the physiology of this species were examined to better predict its survivability in the northern Gulf during winter, when sea surface temperatures fall as low as 15 °C along the coast. Overall, our results show that when the degree of experimental temperature decline was large and rapid, no compensation occurred and the stress response observed mostly reflected cellular processes that minimized damage. Integrated biomarker response values were significantly different between fish rapidly exposed to colder vs. warmer temperatures (declines of −4 °C each day, from 26 to 14 °C), reflected in higher values of blood metabolites and routine metabolic rates observed in fish exposed to 14 and 18 °C respectively, and lower activity of all enzymes, lower protein carbonylation, and higher oxidative damage to lipids in fish exposed to 14 °C. While the phy- siological proxies responded to minimize damage during the rapid-decrease experiment, the same proxies re- flected the consequences of compensation when fish were thermally challenged after a 45 days acclimation at 18 °C. In this case, lower values of blood metabolites and high antioxidant levels and indicators of damages underpinned its pejus lower range. Based on the results of the present work, it seems clear that low winter SSTs in the northern Gulf will slow down the colonization of the inshore area of N. cyanomos. We suggest that the use of physiological cellular stress markers on specimens acquired at the beginning of an invasion should be im- plemented in new standardized experimental protocols, including both rapid increases/decreases of temperature and post-acclimation temperature challenges, to assess the invasiveness potential of aquatic species such as this
Efecto del transporte a larga distancia y de la producción fotoquímica in situ de ozono sobre niveles críticos para la vegetación en Canarias
Ponencia presentada en: 1er Encuentro sobre Meteorología y Atmósfera de Canarias, celebrado en el Puerto de la Cruz, los días 12,13 y 14 de noviembre de 2003. El encuentro estuvo organizado por el Centro Meteorológico Territorial en Canarias Occidental, con la colaboración del Observatorio Atmosférico de Izaña y del Grupo de Física de la Atmósfera de la Facultad de Física (Universidad de La Laguna
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