7,405 research outputs found
Contenido polínico de algunas plantas entomófilas ornamentales en la atmósfera de Salamanca
XV lnternational A.P.L.E. Symposium of Palynolog
Deep into the Water Fountains: The case of IRAS 18043-2116
(Abridged) The formation of large-scale (hundreds to few thousands of AU)
bipolar structures in the circumstellar envelopes (CSEs) of post-Asymptotic
Giant Branch (post-AGB) stars is poorly understood. The shape of these
structures, traced by emission from fast molecular outflows, suggests that the
dynamics at the innermost regions of these CSEs does not depend only on the
energy of the radiation field of the central star. Deep into the Water
Fountains is an observational project based on the results of programs carried
out with three telescope facilities: The Karl G. Jansky Very Large Array
(JVLA), The Australia Telescope Compact Array (ATCA), and the Very Large
Telescope (SINFONI-VLT). Here we report the results of the observations towards
the WF nebula IRAS 180432116: Detection of radio continuum emission in the
frequency range 1.5GHz - 8.0GHz; HO maser spectral features and radio
continuum emission detected at 22GHz, and H ro-vibrational emission lines
detected at the near infrared. The high-velocity HO maser spectral
features, and the shock-excited H emission detected could be produced in
molecular layers which are swept up as a consequence of the propagation of a
jet-driven wind. Using the derived H column density, we estimated a
molecular mass-loss rate of the order of Myr. On the
other hand, if the radio continuum flux detected is generated as a consequence
of the propagation of a thermal radio jet, the mass-loss rate associated to the
outflowing ionized material is of the order of 10Myr.
The presence of a rotating disk could be a plausible explanation for the
mass-loss rates estimated.Comment: 10 pages, 5 figures. Accepted for publication in A&
Estudio aeropalinológico de la familia Oleaceae en la atmósfera de Salamanca (1995-2003)
XV lnternational A.P.L.E. Symposium of Palynolog
Architecture-Aware Configuration and Scheduling of Matrix Multiplication on Asymmetric Multicore Processors
Asymmetric multicore processors (AMPs) have recently emerged as an appealing
technology for severely energy-constrained environments, especially in mobile
appliances where heterogeneity in applications is mainstream. In addition,
given the growing interest for low-power high performance computing, this type
of architectures is also being investigated as a means to improve the
throughput-per-Watt of complex scientific applications.
In this paper, we design and embed several architecture-aware optimizations
into a multi-threaded general matrix multiplication (gemm), a key operation of
the BLAS, in order to obtain a high performance implementation for ARM
big.LITTLE AMPs. Our solution is based on the reference implementation of gemm
in the BLIS library, and integrates a cache-aware configuration as well as
asymmetric--static and dynamic scheduling strategies that carefully tune and
distribute the operation's micro-kernels among the big and LITTLE cores of the
target processor. The experimental results on a Samsung Exynos 5422, a
system-on-chip with ARM Cortex-A15 and Cortex-A7 clusters that implements the
big.LITTLE model, expose that our cache-aware versions of gemm with asymmetric
scheduling attain important gains in performance with respect to its
architecture-oblivious counterparts while exploiting all the resources of the
AMP to deliver considerable energy efficiency
Medidas de manejo del síndrome reproductor y respiratorio porcino (PRRS) basadas en su diagnostico molecular
El síndrome reproductor y respiratorio porcino (PRRS) es una de las enfermedades infecciosas más importantes por el impacto económico que supone para la industria porcina nacional e internacional. Está producida por un virus ARN cuyas principales características son la variabilidad genética y antigénica, sus propiedades inmunomoduladoras y su capacidad para inducir infecciones persistentes. Han sido descritos dos genotipos principales del virus de PRRS, el europeo (EU) y el americano (NA) y últimamente, un tercer genotipo presente solo en Asia La comparación de sus secuencias ha mostrado diferencias genéticas significativas entre ellos, lo que contribuye a que la vacunación sea poco efectiva. Uno de los métodos más empleados para el diagnostico de PRRS es la RT PCR que, acompañada de secuenciación, nos permite determinar el genotipo viral. En los últimos años se han empezado a desarrollar nuevas técnicas de RT-PCR en tiempo real que suponen una mejora sobre las convencionales debido a que presentan ventajas como su mayor sensibilidad, la posibilidad de cuantificar la carga viral o el ahorro de tiempo y material, mejorando el control de la enfermedad. En este trabajo queremos hacer patentes las ventajas y aplicaciones de la RT-PCR en tiempo real para el diagnóstico y el control del virus del Síndrome Respiratorio y Reproductor Porcino.The porcine reproductive and respiratory syndrome (PRRS) is one of the most important infectious diseases in swine national and international industry because of its economic impact. It is caused by a single stranded RNA virus which its main characteristics are: genetic and antigenic variability, immune modulation properties and its capacity to produce persistent infections. There have been described two main genotypes, the North American (NA) and the European (EU) and lately, a third one still limited to Asia. The comparison of its sequences has shown important genetic differences between them, what contributes to the failure of the existing vaccines against it. One of the most used diagnostic methods is the RT-PCR which complemented with sequencing, leads to determinate the viral genotype. In the last years, new RT-PCRs in real time have been developed because they present advantages as higher sensitivity, quantification of viral load or saving on material and time, improving the control of the disease. In this job, we would like to show the advantages and applications of the real time RTPCR for the diagnostic and control of the PRRS virus
High temperature behavior of Sr-doped layered cobaltites Y(Ba1-xSrx)Co2O5.5: phase stability and structural properties
In this article we present a neutron diffraction in-situ study of the thermal
evolution and high-temperature structure of layered cobaltites Y(Ba, Sr)Co2
O5+{\delta}. Neutron thermodiffractograms and magnetic susceptibility
measurements are reported in the temperature range 20 K <= T <= 570 K, as well
as high resolution neutron diffraction experiments at selected temperatures.
Starting from the as-synthesized samples with {\delta} ~ 0.5, we show that the
room temperature phases remain stable up to 550 K, where they start loosing
oxygen and transform to a vacancy-disordered "112" structure with tetragonal
symmetry. Our results also show how the so-called "122" structure can be
stabilized at high temperature (around 450 K) in a sample in which the addition
of Sr at the Ba site had suppressed its formation. In addition, we present the
structural and magnetic properties of the resulting samples with a new oxygen
content {\delta} ~ 0.25 in the temperature range 20 K <= T <= 300 K
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