2,317 research outputs found
Bayesian Networks for Decision-Making and Causal Analysis under Uncertainty in Aviation
Most decisions in aviation regarding systems and operation are currently taken under uncertainty, relaying in limited measurable information, and with little assistance of formal methods and tools to help decision makers to cope with all those uncertainties. This chapter illustrates how Bayesian analysis can constitute a systematic approach for dealing with uncertainties in aviation and air transport. The chapter addresses the three main ways in which Bayesian networks are currently employed for scientific or regulatory decision-making purposes in the aviation industry, depending on the extent to which decision makers rely totally or partially on formal methods. These three alternatives are illustrated with three aviation case studies that reflect research work carried out by the authors
Factores microclimáticos que afectan a la regeneración de Pinus pinaster Ait. en Tierra de Pinares (Segovia)
El objetivo de este estudio fue evaluar los factores micrometeorológicos que afectan a la regeneración del pino resinero en la Tierra de Pinares Segoviana. Se registró durante un período vegetativo completo la temperatura del suelo y la temperatura de la capa de aire más próximo al suelo. La temperatura del suelo alcanzó máximos de 56 ºC desde el mes de julio a septiembre, en períodos de más de 4 horas seguidas durante 2-5 días consecutivos y la temperatura del aire más próximo al suelo, donde viven las plántulas recién nacidas, alcanzó valores de hasta 56 ºC desde junio a septiembre, durante períodos de más de 4,5 horas en periodos de 7 días consecutivos. En las plántulas objeto de estudio se identificaron heridas en el cuello de la raíz lo que indica que las altas temperaturas producen cambios fisiológicos y morfológicos en las plántulas comprometiendo su supervivencia y la de la regeneración de estos montes. El análisis estadístico mostró que los puntos de muestreo seleccionados no presentaron grandes diferencias respecto a las variables microclimáticas consideradas
Estructura europea para la supervisión y el seguimiento de hábitats: aproximación metodológica para España
There is a well defined policy requirement for a practical and reproducible procedure for surveillance and monitoring of habitats in Spain that can subsequently be fitted into a European framework. Any such procedure also needs to incorporate records of the Spanish habitat classification. A procedure is described that will satisfy those requirements and has been field tested both in Spain and in Europe. Rigorous rules and training are required; otherwise changes from baseline records cannot reliably be separated from background noise. The procedure uses the classical plant life forms long used in biogeography and is based on their statistical relationship with the environment. This relationship has been validated statistically and the procedure has also been tested in the field in all European environmental zones and widely in Spain. 130 General Habitat Categories are defined and these are enhanced in the field by recording environmental, site and management qualities to produce a flexible database that can then be interrogated. The rules for mapping the habitats mean that they can be used for descriptive purposes or for monitoring. In conjunction with stratification and subsequent sampling, national estimates of stock and change can then be produced. Finally, based on the previous experience of SISPARES, a methodological scheme is proposed for adapting the approach to Spain. The proposal will allow links to be made between European scale surveillance and monitoring to those already obtained for Spain.en España políticas bien definidas que demandan procedimientos prácticos y reproducibles para llevar a cabo la supervisión y seguimiento de los hábitats, de modo que subsecuentemente puedan ajustarse al marco Europeo. Cualquier procedimiento de estas características necesita poder incorporar datos registrados de la clasificación española de hábitats. Aquí se describe un procedimiento que satisface dichos requisitos y que ha sido probado tanto en España como en el resto de Europa. El método exige reglas rigurosas y entrenamiento de campo; si no los cambios en los registros básicos no se podrán separar de manera fiable de los errores subjetivos cometidos durante la toma de datos. El procedimiento utiliza las clásicas formas de vida, ampliamente utilizadas en estudios biogeográficos y está basado en sus relaciones con el medio ambiente. Esta relación ha sido validada estadísticamente y el procedimiento ha sido probado en el campo en todas las zonas ambientales de Europa. En España, se han definido 130 Categorías Generales de Hábitats y se han verificado en el campo mediante el registro de atributos ambientales, estacionales y de manejo, de forma que puedan ser incluidas en una base de datos suficientemente flexible. Las directrices para la cartografía de hábitats posibilitan su uso descriptivo y permiten su seguimiento. Al mismo tiempo, con la estratificación y subsecuente muestreo, es posible hacer estimaciones nacionales de existencias y de cambios Finalmente, basados en las experiencias previas de SISPARES, se propone un esquema metodológico para adaptar BIOHAB a España. La propuesta permitirá conectar los resultados a escala Europea de supervisión y seguimiento con los obtenidos a escala española
Perception about the importance of feeding in a group of hematologic cancer patients
Introducción: Los pacientes oncohematológicos presentan
habitualmente déficits nutricionales derivados de su
enfermedad, sus tratamientos y efectos secundarios, etc.
Sin embargo, apenas existen datos descriptivos del empleo
de recomendaciones dietéticas, y de la auto-percepción del
paciente de su utilidad en su enfermedad.
Objetivos: Evaluar la percepción de la importancia de
la alimentación en un grupo de pacientes con cáncer
hematológico.
Materiales y métodos: 111 pacientes oncohematológicos
auto-registraron un cuestionario con preguntas sociosanitarias
y de percepción personal de la importancia de la
alimentación en su enfermedad.
Resultados: La edad media fue 40,0 ± 12,8 años (64,86%
mujeres). El diagnóstico y el tratamiento más frecuente fue
linfoma (83,78%) y quimioterapia (92,80%). Un 75% consideró
“muy importante” la relación entre enfermedad
oncohematológica y estado nutricional. Sólo un 54,1%
recibió consejo dietético. Y un 53,2% y 50,5% consideró
que el consumo de suplementos nutricionales mejoraría
su calidad de vida y/o enfermedad respectivamente.
Conclusiones: Un porcentaje importante de pacientes
presentaron estados avanzados de su enfermedad. Sin
embargo, la mitad del colectivo no había recibido pautas
dietéticas a pesar del elevado interés por recibir atención
nutricional. Por tanto, la valoración nutricional del
paciente oncohematológico así como la implementación
de un soporte nutricional personalizado deberían formar
parte de la práctica clínica habitualIntroduction: Oncohematologic patients usually present
nutritional deficits associated with the disease, the treatments
and side effects, etc. However, there are hardly any
descriptive data about the dietary recommendations used
and the patient’s self-perception of its usefulness in their
disease.
Aim: To assess the self-perception of the nutritional
importance in a group of oncohematologic patients.
Materials and methods: 111 oncohematologic patients
self-reported a questionnaire containing items about
socio-sanitary data and self-perception of the nutritional
importance in their disease.
Results: The mean age was 40.0 ± 12.8 years (64.86%
women). The most frequent diagnosis and treatment was
lymphoma (83.78%) and chemoteraphy (92.80%). 75%
considered “very important” relationship between oncohematologic
disease and nutritional status. Only 54.1%
received dietary advice. And 53.2% and 50.5% considered
that the use of nutritional supplements improve quality
of life and/or disease respectively.
Conclusions: A significant percentage of patients had
advanced stages of their disease. However, half the group
had not received dietary advice despite high interest in
receiving nutritional care. Therefore, the nutritional
assessment and the personalized nutritional support
implementation of the patient should be included in routine
clinical practic
Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the response
Pastures are among the most important ecosystems in Europe considering their biodiversity and dis-
tribution area. However, their response to increasing tropospheric ozone (O
3
) and nitrogen (N) deposi-
tion, two of the main drivers of global change, is still uncertain. A new Open-Top Chamber (OTC)
experiment was performed in central Spain, aiming to study annual pasture response to O
3
and N in close
to natural growing conditions. A mixture of six species of three representative families was sowed in the
fi
eld. Plants were exposed for 40 days to four O
3
treatments:
fi
ltered air, non-
fi
ltered air (NFA) repro-
ducing ambient levels and NFA supplemented with 20 and 40 nl l
�
1
O
3
. Three N treatments were
considered to reach the N integrated doses of
“
background
”
,
þ
20 or
þ
40 kg N ha
�
1
. Ozone signi
fi
cantly
reduced green and total aboveground biomass (maximum reduction 25%) and increased the senescent
biomass (maximum increase 40%). Accordingly, O
3
decreased community Gross Primary Production due
to both a global reduction of ecosystem CO
2
exchange and an increase of ecosystem respiration. Nitrogen
could partially counterbalance O
3
effects on aboveground biomass when the levels of O
3
were moderate,
but at the same time O
3
exposure reduced the fertilization effect of higher N availability. Therefore, O
3
must be considered as a stress factor for annual pastures in the Mediterranean areas
Tracing sulfate recycling in the hypersaline Pétrola lake (SE Spain): A combined isotopic and microbiological approach
Sulfur (S) plays a significant role in saline environments, and sulfate (SO4 2−) is an important component of the biogeochemical S-cycle since it acts as the main electron acceptor in anoxic sediments. The purpose of this paper is to evaluate the fate of S, its origin, and processes affecting sulfate outcome in the hypersaline Pétrola Lake in the Castilla-La Mancha region (High Segura Basin, SE Spain). The lake is the terminal discharge zone of an endorheic basin with considerable anthropogenic pressures. Anthropogenic activities (mainly agricultural inputs and wastewater discharge), together with bedrock leaching of sulfate and sulfide-rich sediments, increase dissolved SO4 2− in surface and groundwater up to 123,000 mg/L. The source and fate of sulfate in this environment was investigated coupling hydrochemistry, including hydrogen sulfide (H2S) microprofiles, isotopic analyses (δ34S, δ18OSO4, δ2HH2O, δ18OH2O, and tritium), mineralogical determinations, and molecular biology tools (16S rDNA amplification and sequencing). The origin of dissolved SO4 2− in water is related to pyrite oxidation from Lower Cretaceous sediments, and secondary gypsum dissolution. Under the lake, dissolved SO4 2− decreases with depth, controlled by three main processes: (1) seasonal evaporation cycles, (2) hydrodynamic instability caused by the different density-driven groundwater flow, and (3) sulfate-reduction processes, i.e. dissimilatory bacterial sulfate reduction (BSR). These processes control the continuous recycling of sulfur in the system. Lake water and groundwater are in hydraulic connection, and a density-driven flow (DDF) is able to transport reactive organic matter and dissolved SO4 2− towards the underlying aquifer. Hydrochemical evolution in depth, H2S production (up to 0.024 nmol/cm3·s) and the presence of sulfate-reducing bacteria suggest the existence of BSR processes. However, isotope techniques are insufficient to elucidate BSR processes since their isotopic effect is masked by low isotope fractionation and high SO4 2− concentrations. The pattern here described may be found in other saline basins worldwide
Novel utility-scale photovoltaic plant electroluminescence maintenance technique by means of bidirectional power inverter controller
Nowadays, photovoltaic (PV) silicon plants dominate the growth in renewable energies generation. Utility-scale photovoltaic plants (USPVPs) have increased exponentially in size and power in the last decade and, therefore, it is crucial to develop optimum maintenance techniques. One of the most promising maintenance techniques is the study of electroluminescence (EL) images as a complement of infrared thermography (IRT) analysis. However, its high cost has prevented its use regularly up to date. This paper proposes a maintenance methodology to perform on-site EL inspections as efficiently as possible. First, current USPVP characteristics and the requirements to apply EL on them are studied. Next, an increase over the automation level by means of adding automatic elements in the current PV plant design is studied. The new elements and their configuration are explained, and a control strategy for applying this technique on large photovoltaic plants is developed. With the aim of getting on-site EL images on a real plant, a PV inverter has been developed to validate the proposed methodology on a small-scale solar plant. Both the electrical parameters measured during the tests and the images taken have been analysed. Finally, the implementation cost of the solution has been calculated and optimised. The results conclude the technical viability to perform on-site EL inspections on PV plants without the need to measure and analyse the panel defects out of the PV installation
Quantum Loops in the Resonance Chiral Theory: The Vector Form Factor
We present a calculation of the Vector Form Factor at the next-to-leading
order in the 1/N_C expansion, within the framework of Resonance Chiral Theory.
The calculation is performed in the chiral limit, and with two dynamical quark
flavours. The ultraviolet behaviour of quantum loops involving virtual
resonance propagators is analyzed, together with the kind of counterterms
needed in the renormalization procedure. Using the lowest-order equations of
motion, we show that only a few combinations of local couplings appear in the
final result. The low-energy limit of our calculation reproduces the standard
Chiral Perturbation Theory formula, allowing us to determine the resonance
contribution to the chiral low-energy couplings, at the next-to-leading order
in 1/N_C, keeping a full control of their renormalization scale dependence.Comment: 27+1 pages, 9 figure
Evaluation in a Cytokine Storm Model in Vivo of the Safety and Efficacy of Intravenous Administration of PRS CK STORM (Standardized Conditioned Medium Obtained by Coculture of Monocytes and Mesenchymal Stromal Cells)
Our research group has been developing a series of biological drugs produced by cocul-ture techniques with M2-polarized macrophages with different primary tissue cells and/or mesen-chymal stromal cells (MSC), generally from fat, to produce anti-inflammatory and anti-fibrotic ef-fects, avoiding the overexpression of pro-inflammatory cytokines by the innate immune system at a given time. One of these products is the drug PRS CK STORM, a medium conditioned by allogenic M2-polarized macrophages, from coculture, with those macrophages M2 with MSC from fat, whose composition, in vitro safety, and efficacy we studied. In the present work, we publish the results obtained in terms of safety (pharmacodynamics and pharmacokinetics) and efficacy of the intravenous application of this biological drug in a murine model of cytokine storm associated with severe infectious processes, including those associated with COVID-19. The results demonstrate the safety and high efficacy of PRS CK STORM as an intravenous drug to prevent and treat the cytokine storm associated with infectious processes, including COVID-19
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