A built-in CMOS Total Ionization Dose smart sensor

Total Ionization Dose (TID) is traditionally measured by radiation sensitive FETs (RADFETs) that require a radiation hardened Analog-to-Digital Converter (ADC) stage. This work introduces a TID sensor based on a delay path whose propagation time is sensitive to the absorbed radiation. It presents the following advantages: it is a digital sensor able to be integrated in CMOS circuits and programmable systems such as FPGAs; it has a configurable sensitivity that allows to use this device for radiation doses ranging from very low to relatively high levels; its interface helps to integrate this sensor in a multidisciplinary sensor network; it is self-timed, hence it does not need a clock signal that can degrade its accuracy. The sensor has been prototyped in a 0.35μm technology, has an area of 0.047mm2, of which 22% is dedicated to measuring radiation, and an energy per conversion of 463pJ. Experimental irradiation tests have validated the correct response of the proposed TID sensor

Yield of forage, grain and biomass in eight hybrids of maize with different sowing dates and environmental conditions

The aim was to evaluate yield of forage, grain and biomass and fibre content of eight hybrids of maize (Rio-Grande, Arrayan, Genex 778, Narro 2010, Advance 2203, DAS 2358, P4082W and HT9150W) during two sowing seasons (spring/summer) for two consecutive years at La Laguna in Torreon, Mexico. Once the grain progression of the kernel milk line was ⅓, green forage yield (GFY), dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined. When the corncobs were fully mature, grain yield (GY) and biomass production (TBP) were determined. Weather conditions were recorded during the experiment. The results indicated that maximum temperature was higher and rainfall lower in the summer sowing and second year. Spring sowing had significantly higher yields of GFY, DM, GY and TBP compared to summer sowing. The first year of study showed significantly higher yields regarding GFY, GY and TBP, but FDN, FDA, DM content compared to the second year. The best hybrid for GFY and DM was Rio-Grande; for FDN and FDA was Advance 2203; for GY was HT9150W and finally for TBP was Arrayan. Regardless of the hybrid used and the sowing season, production of maize depended on external factors such as maximum temperature and rainfall; therefore, producers need to consider sowing in spring to avoid the negative effect of high temperatures on plant development.The aim was to evaluate yield of forage, grain and biomass and fibre content of eight hybrids of maize (Rio-Grande, Arrayan, Genex 778, Narro 2010, Advance 2203, DAS 2358, P4082W and HT9150W) during two sowing seasons (spring/summer) for two consecutive years at La Laguna in Torreon, Mexico. Once the grain progression of the kernel milk line was ⅓, green forage yield (GFY), dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined. When the corncobs were fully mature, grain yield (GY) and biomass production (TBP) were determined. Weather conditions were recorded during the experiment. The results indicated that maximum temperature was higher and rainfall lower in the summer sowing and second year. Spring sowing had significantly higher yields of GFY, DM, GY and TBP compared to summer sowing. The first year of study showed significantly higher yields regarding GFY, GY and TBP, but FDN, FDA, DM content compared to the second year. The best hybrid for GFY and DM was Rio-Grande; for FDN and FDA was Advance 2203; for GY was HT9150W and finally for TBP was Arrayan. Regardless of the hybrid used and the sowing season, production of maize depended on external factors such as maximum temperature and rainfall; therefore, producers need to consider sowing in spring to avoid the negative effect of high temperatures on plant development

Variación morfométrica de la pata mesotorácica de Rhagovelia gastrotricha (Hemiptera: Veliidae) en los Andes de Colombia

The Gerromorpha are adapted on the water surface film. These insects exhibit strong associations bet- ween their genetic component, some structural elements of their body and the habitat. The genus Rhagovelia (Veliidae) is found in lotic aquatic ecosystems in heterogeneous microhabitats, where show differences in the middle legs, which are involved in the hydrodynamic of insect. Goals. In order to compare the interpoblational variability of the middle leg of Rhagovelia gastrotricha. Methods. This study analyzed four populations of R. gastrotricha in the sub-Andean foothills of the pacific slope in the west Andes at altitudinal ranges that go from 1000 to 1220 m.a.s.l., between the towns of Ricaurte (forest streams Quebrada Palpis and Quebrada Amor) and Altaquer (Quebrada Ensillada and River Ñambí), in the department of Nariño. Samples were collected in November 2011. We analyzed by means of geometric morphometrics (Fouriers elliptic descriptors) the outline of femur, tibia and tarsus segments, of 40 individuals from four populations of southwestern Nariño. Results. The insects with middle legs that present bigger contour of the femur and tibia were of the water bodies from Quebradas Palpis and Amor; next precedes River Ñambí. The Ensilladas specimens presented minor contour so much of the femur as of the tibia. The variance analysis indicate significant differences (p<0.05) in the outline of the middle leg between populations. Conclusions. Differences are justified by relation with the topography and some physic-chemistry parameters of water bodies.Los Gerromorpha presentan como zona adaptativa la película superficial del agua. Estos insectos exhiben asociaciones definidas entre el hábitat, su componente genético y algunos elementos estructurales. Los Vélidos del gé- nero Rhagovelia encontrados en ecosistemas acuáticos lóticos en microhábitats heterogéneos, evidencian diferencias en las patas medias, las cuales están implicadas en su hidrodinámica. Objetivos. Comparar la variabilidad interpoblacional de la pata media en Rhagovelia gastrotricha. Métodos. Este estudio analiza cuatro poblaciones de R. gastrotricha en el piedemonte Andino de la vertiente Pacífica de la Cordillera Occidental de los Andes en un rango altitudinal entre los 1000 a 1200 m s.n.m. entre las localidades de Ricaurte (Quebrada Palpis y Quebrada Amor) y Altaquer (Quebrada Ensillada y Río Ñambí), en el departamento de Nariño. Los muestreos se realizaron en noviembre de 2011. Se realizó un análisis de morfometría geométrica con descriptores elípticos de Fourier del contorno de los segmentos fémur, tibia y tarso en 40 individuos de cuatro poblaciones del suroeste de Nariño. Resultados. Los insectos con patas medias que presentan mayor contorno en los segmentos fémur y tibia son los de los cuerpos de agua de las Quebradas Palpis y Amor; les pre- ceden los de Río Ñambí. Los especímenes de La Ensillada presentaron menor contorno tanto del fémur como de la tibia. El análisis de varianza muestra diferencias significativas (p<0,05) en el contorno de los tres segmentos de la pata media entre las poblaciones. Conclusiones. Se argumentan las diferencias con relación a la topografía y algunos parámetros físico-químicos de los cuerpos de agua muestreados.

Análisis de la distribución geográfica de las gerridae (Hemiptera, gerromorpha) en los Andes del suroeste de Colombia

Se presentan la distribución geográfica y altitudinal de las Gerridae en la vertiente occidental de la Cordillera Occidental, suroccidente de los Andes de Colombia. La captura de especímenes se realizó en cuerpos de agua en ocho sitios de muestreo, durante los años 2009 y 2010. Se analizó la composición taxonómica respecto del rango geográfico y altitudinal, los biomas y la similitud entre áreas. La distribución geográfica de las Gerridae esta relacionada con el área geográfica, piedemonte y llanura del Pacífico con rango altitudinal (0-2000 m s. n. m.) y tipo de bioma. Las comunidades de Gerridae de la planicie del Pacífico a pesar de encontrarse en el mismo zonobioma difieren en su composición taxonómica debido a diferencias en los cuerpos de agua y microhábitats característicos. Se evidencia la relación inversa entre la altitud y la riqueza de especies.We present the geographical and altitudinal distribution of the Gerridae family on the western slopes of the Western Cordillera of Andes in southwestern Colombia. The specimens were captured in different water bodies, eight sampling sites, during 2009 and 2010. Taxonomic composition was analyzed with respect to geographical and altitudinal range, biomes and the similarity between areas. The geographical distribution of the Gerridae is related to geographic area, foothills and Plain Pacific, altitudinal range (0-2000 masl) and features of type of biome. The communities of Gerridae from Pacific Plain are in the same zonobioma but differ in taxonomic composition due to differences in water bodies and microhabitats own. On the other hand we show the inverse relationship between altitude and species richness

Multi-Proxy Approach for Identifying Heinrich Events in Sediment Cores from Hatton Bank (NE Atlantic Ocean)

A series of six gravity cores has been used to reconstruct the depositional history of Hatton Bank (Rockall Plateau, NE Atlantic Ocean). The cores have been studied for magnetic susceptibility (MS), geochemical composition, grain size distribution, and a semi-quantitative foraminiferal association. Two main interbedded facies have been described: (i) calcareous ooze; and (ii) lithogenous silt. The study reveals prominent peaks from the MS signal, silt, Mg/Ca, Fe/Ca, Al/Ca, and Rare Earth Elements normalised by Continental Crust (REE/CC), which are sensitive indicators for Heinrich events (H1, H2, H3, H4, and H5) and ash layers. These peaks may relate to alternations in dominance of the calcareous and lithogenic facies. The sediment displays a high percentage of carbonate in interglacial layers but is lithogenic-dominated in glacial stages. The layers with prominent lithic-rich and foraminifera-poor sediments (established as Heinrich layers) may be related to a possible palaeoclimatic effect, where freshwater discharged during iceberg melting may have reduced the formation of North Atlantic Deep Water (NADW). In the study area, the mean sedimentation rates for the last glacial as ~4.2 cm ka−1 and ~1.4 cm ka−1 for the last ~18 ka (interglacial period) have been estimated. Besides this evidence, Fe/Ca and MS peaks may reflect the presence of basalt, either introduced through ice-rafting or transported and redistributed by bottom currents in the study area. Certain indices, including MS and Fe/Ca, are proposed as good proxies for detecting Heinrich events and ash layers in the Hatton Bank sediments and, in consequence, are parameters that can be used to infer strengthened/weakened NADW formation, according to stadials/interstadials. Moreover, we suggest that the northernmost boundary of the area with evidence of Heinrich events may be situated around 57°38′ N in the Hatton–Rockall area, at least for H4, based on the variation of the Mg/Ca and Fe/Ca curves

Use of 2-D Dige and preparative denaturing IEF to enhance sensitivity in the differential protein expression analysis of Candida Albicans yeast-to-Hypha transition

Comunicaciones a congreso

Crisis de deuda soberana en la Eurozona

RESUMEN: La crisis financiera internacional de 2008-2009, cuyos efectos se propagaron desde los Estados Unidos hasta Europa y el resto del Mundo, potencializó y detonó una serie de problemas estructurales existentes en algunas economías europeas. Concretamente, el mayor endeudamiento público, empleado como motor de crecimiento y despegue de las diversas economías, alcanzó niveles que dejan en jaque la sostenibilidad de las finanzas públicas y con ello la totalidad del aparato económico, en economías como las de Grecia, España, Irlanda y Portugal. Ante tal situación, los planes de ajuste no se han hecho esperar, tanto desde los países directamente afectados como de los demás miembros de la Eurozona. Este panorama ha puesto en entredicho el futuro de este bloque económico al igual que la efectividad de los controles y castigos para aquellas economías que no presentan un manejo adecuado de las finanzas públicas.ABSTRACT: The international financial crisis of 2008-2009, whose effects extended from the United States to Europe and the rest of the world, potentiated and detonated a series of structural issues in some European economies. Specifically, the higher public debt, used as a growth engine in some of them, reached record levels that left in check the sustainability of public finances, and thus, of the entire economic system of countries such as Greece, Spain, Ireland and Portugal. Given the situation, adjustment plans have been common both from the directly affected countries and from the other members of the economic zone. The picture has questioned the future of the Eurozone as well as of the effectiveness of the controls and penalties for those economies without a proper management of their public finances

Integrated luminescent chemical microsensors based on GaN LEDs for security applications using smartphones

Development of PCB-integrateable microsensors for monitoring chemical species is a goal in areas such as lab-on-a-chip analytical devices, diagnostics medicine and electronics for hand-held instruments where the device size is a major issue. Cellular phones have pervaded the world inhabitants and their usefulness has dramatically increased with the introduction of smartphones due to a combination of amazing processing power in a confined space, geolocalization and manifold telecommunication features. Therefore, a number of physical and chemical sensors that add value to the terminal for health monitoring, personal safety (at home, at work) and, eventually, national security have started to be developed, capitalizing also on the huge number of circulating cell phones. The chemical sensor-enabled “super” smartphone provides a unique (bio)sensing platform for monitoring airborne or waterborne hazardous chemicals or microorganisms for both single user and crowdsourcing security applications. Some of the latest ones are illustrated by a few examples. Moreover, we have recently achieved for the first time (covalent) functionalization of p- and n-GaN semiconductor surfaces with tuneable luminescent indicator dyes of the Ru-polypyridyl family, as a key step in the development of innovative microsensors for smartphone applications. Chemical “sensoring” of GaN-based blue LED chips with those indicators has also been achieved by plasma treatment of their surface, and the micrometer-sized devices have been tested to monitor O2 in the gas phase to show their full functionality. Novel strategies to enhance the sensor sensitivity such as changing the length and nature of the siloxane buffer layer are discussed in this paper

Asymptotics of orthogonal polynomials generated by a Geronimus perturbation of the Laguerre measure

This paper deals with monic orthogonal polynomials generated by a Geronimus canonical spectral transformation of the Laguerre classical measure for x in [0,?), ? > ?1, a free parameter N and a shift c<0. We analyze the asymptotic behavior (both strong and relative to classical Laguerre polynomials) of these orthogonal polynomials as n tends to infinity