Escalabilidad de los Sistemas de Correo Electrónico

La implementación de sistemas de e-mail que escalen fácilmente hasta varios miles o millones de usuarios, no es trivial. En este trabajo se ve un ejemplo de un sistema de mail altamente escalable, probado hoy en día para cientos de miles de usuarios basado en arquitecturas abiertas. El sistema fue desarrollado en Sinectis S.A. y se utiliza exitosamente como infraestructura de e-mail.

Time resolved magneto-optical spectroscopy on InGaAs nanostructures grown on (311)A and (100)-oriented substrates

We present a time-resolved magneto-photoluminescence study of In0.5Ga0.5As self-organized nanostructures grown on (100) and (311)A-oriented substrates by molecular beam epitaxy. The (311)A-oriented samples have a corrugated surface realizing a sort of quantum wire array, whereas the (100) samples exhibit Stranski–Krastanow islands. The different morphology of the nanostructures is reflected in the different electron/hole wave-function confinement along the three directions (perpendicular and parallel to the growth direction). We discuss the effects of the magnetic field (up to 8 T) on the recombination mechanism in these InGaAs nanostructures and on the transient dynamics of photoluminescence. We observe a clear decrease of the photoluminescence decay time with magnetic field flux indicating the exciton nature of the radiative low-temperature recombination processes

Incidencia del fuego en un gradiente altitudinal de las sierras del centro de la Argentina

En los ecosistemas de montaña, la distribución de la vegetación a lo largo del gradiente altitudinal fue tradicionalmente interpretada en términos de la temperatura decreciente desde la base hacia arriba; pero los fuegos pueden co-variar con el gradiente de altitud, también cumpliendo un papel importante. En las montañas del centro de la Argentina (500-2800 m s. n. m.), los fuegos son uno de los disturbios principales y pueden cumplir una función importante en modular la dinámica de la vegetación a lo largo de la altitud. Sin embargo, hasta ahora ningún estudio describió la incidencia del fuego a lo largo del gradiente altitudinal. Nosotros comparamos la incidencia del fuego entre cinco intervalos altitudinales usando una base de datos de fuegos espacialmente explícita, de 18 años, derivada de sensores remotos. Para cada intervalo, descartamos las áreas no combustibles y calculamos para cada año la incidencia del fuego como el porcentaje de área quemada. La incidencia de fuego mostró un patrón unimodal a lo largo del gradiente de altitud. Las incidencias más altas se registraron a altitudes intermedias, en los intervalos de 1301-1700 m y 901-1300 m, con 3.2% y 2.7% de incidencia anual, respectivamente. La incidencia de fuego más baja se registró en el intervalo inferior (500-900 m), con 1.3% quemado anualmente, en promedio. La mayor incidencia del fuego observada a altitudes intermedias es consistente con un aumento importante de la cobertura de pastizales por encima de los 900 m s. n. m., con una simultánea reducción en la extensión de bosques. Hacia mayores altitudes, la menor incidencia del fuego es consistente con la presencia de barreras impuestas por la topografía y por las áreas rocosas no combustibles, y con las condiciones más húmedas. La mayor incidencia de fuegos observada a altitudes intermedias puede estar limitando la expansión de bosques en dichas áreas. A mayores altitudes, la baja cobertura arbórea podría estar explicada por una combinación de fuegos y presión ganadera. Nuestro estudio es el primero que muestra cómo varía la incidencia del fuego a lo largo del gradiente completo de altitud, brindando una herramienta importante para entender la distribución de la vegetación y planificar estrategias de conservación y restauración.In mountain ecosystems, vegetation distribution along elevation has been traditionally interpreted in terms of the decreasing temperature from base to top, but wildfires may co-vary with the elevation gradient, also playing an important role. In the mountains of central Argentina (500-2800 m a. s. l.) wildfires are one of the main disturbances, which may have an important role in shaping vegetation dynamics along elevation. However, to date, no study described the fire pattern along the elevation gradient. We compared fire incidence among five elevation intervals using an 18-year spatially explicit fire database derived from remote sensing. For each interval, we discarded unburnable areas and calculated fire incidence per year as the percentage of burned area. Fire incidence showed a hump-shaped pattern along the elevation gradient. The highest fire incidence occurred at intermediate elevations, in the 1301-1700 m and 901-1300 m intervals, with averages of 3.2 and 2.7% of the area being burned annually, respectively. The lowest fire incidence occurred at the lowest interval (500-900 m), with 1.3% being burned annually on average. The greater fire incidence observed at intermediate elevations is consistent with a sharp increase in the cover of grasslands above 900 m a. s. l., with an associated reduction in forest occupation. Towards higher elevations, the lower fire incidence is consistent with the presence of topographic breaks, greater proportion of unburnable surfaces that work as firebreaks and moister conditions. The greater fire incidence observed at intermediate elevations may be limiting forest expansion in those areas. At higher elevations the low forest cover may be explained by a combination of fire and livestock pressure. Our study is the first to show how fire incidence varies along the complete elevation gradient, bringing an important tool to understand vegetation distribution and plan future conservation and restoration strategies.Fil: Argañaraz, Juan Pablo. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Cingolani, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bellis, Laura Marisa. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica. Cátedra de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Giorgis, Melisa Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin

Local degradation of selectively oxidized AlGaAs/AlAs distributed Bragg reflectors in lateral-injection vertical-cavity surface-emitting lasers

We show the local degradation of a selectively oxidized top distributed Bragg reflector (DBR) in a lateral-junction vertical-cavity surface-emitting laser (LJ-VCSEL) working at room temperature in continuous-wave operation. The measurements were carried out by a scanning microluminescence system used in reflection mode. The injection of a few milliamps in continuous-wave operation at room temperature in the LJ-VCSEL induces damage both in the DBRs and in the active area. The submicron resolution maps of the reflected laser intensity, recorded from the top surface of the LJ-VCSEL, show a strong local change in the top DBR reflectivity before and after current injection. The μ-photoluminescence map, recorded after the device failure, shows that the radiative recombination is strongly decreased in the damaged area of the device

Subnanometer Local Temperature Probing and Remotely Controlled Drug Release Based on Azo-Functionalized Iron Oxide Nanoparticles

Local heating can be produced by iron oxide nanoparticles (IONPs) when exposed to an alternating magnetic field (AMF). To measure the temperature profile at the nanoparticle surface with a subnanometer resolution, here we present a molecular temperature probe based on the thermal decomposition of a thermo-sensitive molecule, namely, azobis[N-(2-carboxyethyl)-2-methylpropionamidine]. Fluoresceineamine (FA) was bound to the azo molecule at the IONP surface functionalized with poly(ethylene glycol) (PEG) spacers of different molecular weights. Significant local heating, with a temperature increase up to 45 °C, was found at distances below 0.5 nm from the surface of the nanoparticle, which decays exponentially with increasing distance. Furthermore, the temperature increase was found to scale linearly with the applied field at all distances. We implemented these findings in an AMF-triggered drug release system in which doxorubicin was covalently linked at different distances from the IONP surface bearing the s..

Using Drosophila melanogaster as a Model for Genotoxic Chemical Mutational Studies with a New Program, SnpSift

This paper describes a new program SnpSift for filtering differential DNA sequence variants between two or more experimental genomes after genotoxic chemical exposure. Here, we illustrate how SnpSift can be used to identify candidate phenotype-relevant variants including single nucleotide polymorphisms, multiple nucleotide polymorphisms, insertions, and deletions (InDels) in mutant strains isolated from genome-wide chemical mutagenesis of Drosophila melanogaster. First, the genomes of two independently isolated mutant fly strains that are allelic for a novel recessive male-sterile locus generated by genotoxic chemical exposure were sequenced using the Illumina next-generation DNA sequencer to obtain 20- to 29-fold coverage of the euchromatic sequences. The sequencing reads were processed and variants were called using standard bioinformatic tools. Next, SnpEff was used to annotate all sequence variants and their potential mutational effects on associated genes. Then, SnpSift was used to filter and select differential variants that potentially disrupt a common gene in the two allelic mutant strains. The potential causative DNA lesions were partially validated by capillary sequencing of polymerase chain reaction-amplified DNA in the genetic interval as defined by meiotic mapping and deletions that remove defined regions of the chromosome. Of the five candidate genes located in the genetic interval, the Pka-like gene CG12069 was found to carry a separate pre-mature stop codon mutation in each of the two allelic mutants whereas the other four candidate genes within the interval have wild-type sequences. The Pka-like gene is therefore a strong candidate gene for the male-sterile locus. These results demonstrate that combining SnpEff and SnpSift can expedite the identification of candidate phenotype-causative mutations in chemically mutagenized Drosophila strains. This technique can also be used to characterize the variety of mutations generated by genotoxic chemicals

Thermochronology of the Ventana Ranges and Claromecó Basin, Argentina: Record of Gondwana breakup and South Atlantic passive margin dynamics

The Ventana Ranges and the neighboring Claromecó basin display multiple extensional and compressional tectonic events throughout their Phanerozoic evolution. A passive continental margin setting during the early Paleozoic changed to a compressional system in the late Paleozoic, for which the Ventana Ranges are its fossilized fold and thrust belt and the Claromecó Basin, to the north-northeast, its associated foreland basin. The thermochronology study presented here and the cooling ages obtained for the Ventana Ranges are interpreted as a long-lived, probably multi-stage, exhumation event that occurred throughout the Mesozoic. The ZFT and AFT ages indicate that the Silurian, Devonian, Carboniferous and Permian units cooled during the Late Triassic to Early Jurassic (from 204.4 ± 18.8 to 146.5 ± 11.6 Ma). These ages, consistent with rifting events described for the neighboring Colorado basin (to the south-southeast), are interpreted as exhumation in the rift´s northern flank. In the Claromecó Basin, a cooling event is indicated from the AFT PAZ data for the late Early Cretaceous (Barremian-Aptian, 125.8 ± 10.6 Ma), interpreted as a part of passive margin exhumation during the drift stage after the South Atlantic opening in the Valanginian-Hauterivian. The obtained ages indicate exhumation in the basin flank and are consistent with the different rifting events previously interpreted for Colorado basin.Fil: Arzadún, Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. lA - Te Andes S.A. Laboratorio de Termocronología de Los Andes; ArgentinaFil: Lovecchio, Juan Pablo. Yacimientos Petrolíferos Fiscales S. A.; ArgentinaFil: Becchio, Raul Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Salta; ArgentinaFil: Uriz, Norberto Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Cingolani, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Febbo, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Hernández, Roberto. lA - Te Andes S.A. Laboratorio de Termocronología de Los Andes; ArgentinaFil: Bolatti, Nestor. Yacimientos Petrolíferos Fiscales S. A.; ArgentinaFil: Kress, Pedro. Yacimientos Petrolíferos Fiscales S. A.; Argentin

Clinical application of a cancer genomic profiling assay to guide precision medicine decisions

AIM: Develop and apply a comprehensive and accurate next-generation sequencing based assay to help clinicians to match oncology patients to therapies. MATERIALS and METHODS: The performance of the CANCERPLEX(R) assay was assessed using DNA from well-characterized routine clinical formalin-fixed paraffin-embedded (FFPE) specimens and cell lines. RESULTS: The maximum sensitivity of the assay is 99.5% and its accuracy is virtually 100% for detecting somatic alterations with an allele fraction of as low as 10%. Clinically actionable variants were identified in 93% of patients (930 of 1000) who underwent testing. CONCLUSION: The test\u27s capacity to determine all of the critical genetic changes, tumor mutation burden, microsatellite instability status and viral associations has important ramifications on clinical decision support strategies, including identification of patients who are likely to benefit from immune checkpoint blockage therapies

Estudio acústico del Teatro de Cámara de City Bell

El Teatro de Cámara de City Bell fue inaugurado en marzo de 2003. Diseñado por el Arq. Manuel Cortés junto a Sebastián Cortés, es una construcción de 300 m2 que se ubica en Diagonal Urquiza Nro. 347, City Bell, La Plata. El proyecto fue una iniciativa de Juan Carlos Carassale, quien junto a su familia decidió realizar este emprendimiento abierto a la comunidad que es administrado por la asociación sin fines de lucro "Lumen Artis" integrada por vecinos de la zona. La sala ha sido diseñada para conciertos de música de cámara instrumental y vocal. En la misma también se realizan obras de teatro, danza, música tradicional argentina e internacional y cine. El diseño acústico estuvo a cargo de Gustavo Basso.Mesa: Enfoques en perspectiva: prácticas y lenguajes artísticos IIFacultad de Bellas Arte

Estudio acústico del Teatro de Cámara de City Bell

El Teatro de Cámara de City Bell fue inaugurado en marzo de 2003. Diseñado por el Arq. Manuel Cortés junto a Sebastián Cortés, es una construcción de 300 m2 que se ubica en Diagonal Urquiza Nro. 347, City Bell, La Plata. El proyecto fue una iniciativa de Juan Carlos Carassale, quien junto a su familia decidió realizar este emprendimiento abierto a la comunidad que es administrado por la asociación sin fines de lucro "Lumen Artis" integrada por vecinos de la zona. La sala ha sido diseñada para conciertos de música de cámara instrumental y vocal. En la misma también se realizan obras de teatro, danza, música tradicional argentina e internacional y cine. El diseño acústico estuvo a cargo de Gustavo Basso.Mesa: Enfoques en perspectiva: prácticas y lenguajes artísticos IIFacultad de Bellas Arte