4,081 research outputs found
Discussion on complexity and TCAS indicators for coherent safety net transitions
Transition between Separation Management in ATM
and Collision Avoidance constitutes a source of potential risks due
to non-coherent detection and resolution clearances between them.
To explore an operational integration between these two safety
nets, a complexity metric tailored for both Separation
Management and Collision Avoidance, based on the intrinsic
complexity, is proposed.
To establish the framework to compare the complexity metric with
current Collision Avoidance detection metrics, a basic pair-wise
encounter model has been considered. Then, main indicators for
horizontal detection of TCAS, i.e. tau and taumod, have been
contrasted with the complexity metric.
A simple method for determining the range locus for specific
TCAS tau values, depending on relative speeds and encounter
angles, was defined. In addition, range values when detection
thresholds were infringed have been found to be similar, as well as
its sensitivity to relative angles.
Further work should be conducted for establishing a framework
for the evaluation and validation of this complexity metric. This
paper defines basic principles for an extended evaluation,
including multi-encounter scenarios and longer look ahead times
Inducción rizogénica en estacas semileñosas de Berberidopsis corallina
- Latsague, M. ; Sáez, P.; Cifuentes, P.; Yáñez ,Y. Laboratorio de Ecofisiología Vegetal y Citogenética, Facultad de Recursos Naturales, Universidad Católica de Temuco, Chile.Berberidopsis corallina (michay rojo) es una especie endémica, catalogada como especie
“En Peligro de Extinción”. Su persistente disminución está asociada a tala y competencia
con Eucalyptus spp. y P. radiata. A raíz de continuas campañas realizadas por
organizaciones ambientales, se han enfocado esfuerzos en intentar conservar los bosques
nativos remanentes. Entre las herramientas de gestión a esta problemática se cuenta la
propagación vegetativa, como una forma de aumentar el numero de individuos y acortar el
período vegetativo, sin embargo, existe escasa información respecto a la propagación de
michay rojo, por lo que, el objetivo del estudio fue evaluar la respuesta al tratamiento de
enraizamiento de estacas semileñosas, como un aporte a la conservación de la especie. Las
estacas se colectaron en marzo del 2007 en el sector Villa las Araucarias, al Sur de la
Cordillera de Nahuelbuta, región de la Araucanía. Las estacas se trataron con Ácido Indol
Butírico (AIB) en distintas concentraciones (0, 500,1000 y 1500 ppm). Luego de cinco
meses en cama caliente, se obtuvo un 87% de enraizamiento total. La concentración 1000
ppm de AIB mostró los mejores resultados respecto al proceso de rizogénesis con un 90%
de enraizamiento, encontrando la mayor longitud de raíces en este mismo tratamiento con
un promedio de 13,64 cm. El mayor número de raíces se obtuvo en el tratamiento 1500
ppm de AIB con un valor promedio de 38,11 raíces por estaca. Se concluye que michay
rojo puede ser reproducido vegetativamente a través de la rizogénesis de estacas tratadas
con AIB
Phosphoproteomics data classify hematological cancer cell lines according to tumor type and sensitivity to kinase inhibitors
This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Software infrastructure for solving non-linear partial differential equations and its application to modelling crustal fault systems
In this paper we will give a brief introduction into the Python-based modelling language escript. We will present a model for the dynamics of fault systems in the Earth's crust and then show how escript is used to implement solution algorithms for a dynamic as well as a quasi-static scenario
Study of SREBP1 and SERBP2 in peripheral blood mononuclear cells fron hypercholesterolemic rabbits
Peripheral blood mononuclear cells are a possible biomarker that could reveal molecular alterations before the development of the disease. Therefore, the objective of the present investigation is to study molecular and genetic changes that indicate metabolic modifications even with normal biochemical values. SERBP1 and SERBP2 are proteins involved in lipid metabolic. These molecules can be expressed in peripheral blood mononuclear cells. This allows study tissue changes without resorting to biopsies. In this study, one control group of New Zealand rabbits was fed with a balanced feed (C) and another group received the same balanced feed supplemented with 17% fat (F). These animals did not receive fructose overload, maintaining constant concentrations of carbohydrates and protein in both groups. In biochemical tests from both groups were observed similar levels of glucose (C group: 140.7 + 28.4 mg/dl / F group: 118.3 +12.0 mg/dl) and triglyceride (C group: 144.1 +15.5 mg/dl / F group: 135.6 +8.3 mg/dl), while F group showed increased levels of cholesterol (42.8 +21.6mg/dl) compared with C group (27.1 +4.5 mg/dl). However, there is variability in the cholesterol values because some animals of the F group do not experience significant increment despite the intake of fat. This interesting finding leads to the hypothesis that changes in lipid metabolism can be examined by the expression of different genes early. As preliminary results, we observed by immunohistochemistry the presence nuclear of SREBP1 and SREBP2 in lymphocytes of the F group, while in C group was not observed immunoreaction or cytoplasmic signal. This result is indicating an activation of the lipid metabolism before being able to observe changes at a biochemical level.Fil: Saez, Aldana. Universidad "Juan Agustín Maza"; ArgentinaFil: Mussi, Jesica. Universidad "Juan Agustín Maza"; ArgentinaFil: Funes, Abi Karenina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Colombo, Regina Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Fornes, Miguel Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Saez Lancellotti, Tania Emilce Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Boarelli, P. Universidad "Juan Agustín Maza"; ArgentinaXXXVI Reunión Científica Anual de la Sociedad de Biología de CuyoMendozaArgentinaSociedad Argentina de Biologí
The coupon collector urn model with unequal probabilities in ecology and evolution
International audienceThe sequential sampling of populations with unequal probabilities and with replacement in a closed population is a recurrent problem in ecology and evolution. Examples range from biodiversity sampling, epidemiology to the estimation of signal repertoire in animal communication. Many of these ques- tions can be reformulated as urn problems, often as special cases of the coupon collector problem, most simply expressed as the number of coupons that must be collected to have a complete set. We aimed to apply the coupon collector model in a comprehensive manner to one example—hosts (balls) being searched (draws) and parasitized (ball colour change) by parasitic wasps— to evaluate the influence of differences in sampling probabilities between items on collection speed. Based on the model of a complete multinomial process over time, we define the distribution, distribution function, expectation and variance of the number of hosts parasitized after a given time, as well as the inverse problem, estimating the sampling effort. We develop the relationship between the risk distribution on the set of hosts and the speed of parasitization and propose a more elegant proof of the weak stochastic dominance among speeds of parasitization, using the concept of Schur convexity and the ‘Robin Hood transfer’ numerical operation. Numerical examples are provided and a conjecture about strong dominance—an ordering characteristic of random variables—is proposed. The speed at which new items are discovered is a function of the entire shape of the sampling probability distribution. The sole comparison of values of variances is not sufficient to compare speeds associated with different distributions, as generally assumed in ecological studies
Confirmation of and Variable Energy Injection by a Near-Relativistic Outflow in APM 08279+5255
We present results from multi-epoch spectral analysis of XMM-Newton and
Chandra observations of the broad absorption line (BAL) quasar APM 08279+5255.
Our analysis shows significant X-ray BALs in all epochs with rest-frame
energies lying in the range of ~ 6.7-18 keV. The X-ray BALs and 0.2-10 keV
continuum show significant variability on timescales as short as 3.3 days
(proper time) implying a source size-scale of ~ 10 r_g, where r_g is the
gravitational radius. We find a large gradient in the outflow velocity of the
X-ray absorbers with projected outflow velocities of up to 0.76 c. The maximum
outflow velocity constrains the angle between the wind velocity and our line of
sight to be less than ~ 22 degrees. We identify the following components of the
outflow: (a) Highly ionized X-ray absorbing material (2.9 < logxi < 3.9) and a
column density of log N_H ~ 23 outflowing at velocities of up to 0.76 c. (b)
Low-ionization X-ray absorbing gas with log N_H ~ 22.8. We find that flatter
spectra appear to result in lower outflow velocities. Based on our spectral
analysis of observations of APM 08279+5255 over a period of 1.2 years (proper
time) we estimate the mass-outflow rate and efficiency of the outflow to have
varied between 16(-8,+12) M_solar yr^-1 and 64(-40,+66) M_solar yr^-1 and
0.18(-0.11,+0.15) to 1.7(-1.2+1.9), respectively. Assuming that the outflow
properties of APM 08279+5255 are a common property of most quasars at similar
redshifts, our results then imply that quasar winds are massive and energetic
enough to influence significantly the formation of the host galaxy, provide
significant metal enrichment to the interstellar medium and intergalactic
medium, and are a viable mechanism for feedback at redshifts near the peak in
the number density of galaxy mergers.Comment: 27 pages, includes 12 figures, accepted for publication in Ap
GeneCodis: interpreting gene lists through enrichment analysis and integration of diverse biological information
GeneCodis is a web server application for functional analysis of gene lists that integrates different sources of information and finds modular patterns of interrelated annotations. This integrative approach has proved to be useful for the interpretation of high-throughput experiments and therefore a new version of the system has been developed to expand its functionality and scope. GeneCodis now expands the functional information with regulatory patterns and user-defined annotations, offering the possibility of integrating all sources of information in the same analysis. Traditional singular enrichment is now permitted and more organisms and gene identifiers have been added to the database. The application has been re-engineered to improve performance, accessibility and scalability. In addition, GeneCodis can now be accessed through a public SOAP web services interface, enabling users to perform analysis from their own scripts and workflows. The application is freely available at http://genecodis.dacya.ucm.e
Beam heat load analysis with COLDDIAG: a cold vacuum chamber for diagnostics
The knowledge of the heat intake from the electron beam is essential to design the cryogenic layout of superconducting insertion devices. With the aim of measuring the beam heat load to a cold bore and understanding the responsible mechanisms, a cold vacuum chamber for diagnostics (COLDDIAG) has been built. The instrumentation comprises temperature sensors, pressure gauges, mass spectrometers and retarding field analyzers, which allow to study the beam heat load and the influence of the cryosorbed gas layer. COLDDIAG was installed in the storage ring of the Diamond Light Source from September 2012 to August 2013. During this time measurements were performed for a wide range of machine conditions, employing the various measuring capabilities of the device. Here we report on the analysis of the measured beam heat load, pressure and gas content, as well as the low energy charged particle flux and
spectrum as a function of the electron beam parameters
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