468 research outputs found
Spectroscopy along flerovium decay chains: Discovery of 280Ds and an excited state in 282Cn
ArtÃculo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMA nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z = 114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions 48Ca + 242Pu and 48Ca + 244Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to 286Fl and 288Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely 282Cn. Spectroscopy of 288Fl decay chains fixed Qα = 10.06(1) MeV. In one case, a Qα = 9.46(1)-MeV decay from 284Cn into 280Ds was observed, with 280Ds fissioning after only 518 μs. The impact of these findings, aggregated with existing data on decay chains of 286,288Fl, on the size of an anticipated shell gap at proton number Z = 114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformatio
Extracting Information about the Rotator Cuff from Magnetic Resonance Images Using Deterministic and Random Techniques
We consider some methods to extract information about the rotator cuff based on magnetic resonance images; the study aims to define an alternative method of display that might facilitate the detection of partial tears in the supraspinatus tendon. Specifically, we are going to use families of ellipsoidal triangular patches to cover the humerus head near the affected area. These patches are going to be textured and displayed with the information of the magnetic resonance images using the trilinear interpolation technique. For the generation of points to texture each patch, we propose a new method that guarantees the uniform distribution of its points using a random statistical method. Its computational cost, defined as the average computing time to generate a fixed number of points, is significantly lower as compared with deterministic and other standard statistical techniques
Thin and thick cloud top height retrieval algorithm with the Infrared Camera and LIDAR of the JEM-EUSO Space Mission
The origin of cosmic rays have remained a mistery for more than a century.
JEM-EUSO is a pioneer space-based telescope that will be located at the
International Space Station (ISS) and its aim is to detect Ultra High Energy
Cosmic Rays (UHECR) and Extremely High Energy Cosmic Rays (EHECR) by observing
the atmosphere. Unlike ground-based telescopes, JEM-EUSO will observe from
upwards, and therefore, for a properly UHECR reconstruction under cloudy
conditions, a key element of JEM-EUSO is an Atmospheric Monitoring System
(AMS). This AMS consists of a space qualified bi-spectral Infrared Camera, that
will provide the cloud coverage and cloud top height in the JEM-EUSO Field of
View (FoV) and a LIDAR, that will measure the atmospheric optical depth in the
direction it has been shot. In this paper we will explain the effects of clouds
for the determination of the UHECR arrival direction. Moreover, since the cloud
top height retrieval is crucial to analyze the UHECR and EHECR events under
cloudy conditions, the retrieval algorithm that fulfills the technical
requierements of the Infrared Camera of JEM-EUSO to reconstruct the cloud top
height is presently reported.Comment: 5 pages, 6 figures, Atmohead Conference 201
Planification of conservation and preservation program in Maneto Group dog
In the present paper we are describing the planification of a conservation and preservation programme of the Maneto dog breed group in developing under two consecutive phases. Firstly we show the results obtained in the ethnogenetic characterization (mopho-structural and external), but also a preliminary report of the functional, genetic and environmental information collection, using a zootechnic inquiry as applications of the first phase. In the second phase we are proposing some actuation destines to the reproducers evaluation and the planification of the breeding system to develop a complete conservation programme for this breed.En el presente trabajo se describen la planificación de un programa de conservación y preservación en la Agrupación Racial del Perro Maneto a desarrollar en dos fases sucesivas. Primeramente se muestran los resultados obtenidos en la caracterización etnogenética (morfoestructural y faneróptica) asà como un esbozo de la recogida de información funcional, genética y del entorno a través de una encuesta zootécnica como acciones englobadas en la primera fase. En la segunda fase se proponen actuaciones encaminadas a la valoración de reproductores y la planificación de los sistemas de crÃa conducentes al establecimiento de un programa de conservación integral en la raza
Reinforced silica-carbon nanotube monolithic aerogels synthesised by rapid controlled gelation
This work introduces a new synthesis procedure for obtaining homogeneous silica hybrid aerogels with carbon nanotube contents up to 2.50 wt.%. The inclusion of nanotubes in the highly porous silica matrix was performed by a two-step sol–gel process, resulting in samples with densities below 80 mg/cm3. The structural analyses (N2 physisorption and SEM) revealed the hierarchical structure of the porous matrix formed by nanoparticles arranged in clusters of 100 and 300 nm in size, specific surface areas around 600 m2/g and porous volumes above 4.0 cm3/g. In addition, a relevant increase on the mechanical performance was found, and an increment of 50% for the compressive strength and 90% for the maximum deformation were measured by uniaxial compression. This reinforcement was possible thanks to the outstanding dispersion of the CNT within the silica matrix and the formation of Si–O–C bridges between nanotubes and silica matrix, as suggested by FTIR. Therefore, the original synthesis procedure introduced in this work allows the fabrication of highly porous hybrid materials loaded with carbon nanotubes homogeneously distributed in the space, which remain available for a variety of technological applications
Halotolerant Copepoda in South American inland saline waters
The zooplankton in South American saline waters is mainly dominated by copepods at salinities lower than 90 g/l, whereas at salinities above 90 g/l Artemia sp. is totally dominant. The aim of the present study is to analyse the salinity range of halophilic copepods on the basis of a literature review for South American saline inland waters. The calanoid Boeckella poopoensis Marsh, 1906, is widespread on the South American Altiplano and southern Argentinian plains, and in southern Patagonian shallow ponds. In the upper part of the salinity range, 20-90 g/l, B. poopoensis is the only copepod in the zooplankton of southern Patagonian and Altiplano shallow lakes. In the salinity range 5-20 g/l B. poopoensis may co-exist with B. palustris (Harding, 1955), two cyclopoids and an harpacticoid, and at salinities lower than 5 g/l it may co-exist with an even wider range of copepod species. Ecological and biogeographical aspects are also discusse
Design of the Front End Electronics for the Infrared Camera of JEM-EUSO, and manufacturing and verification of the prototype model
The Japanese Experiment Module (JEM) Extreme Universe Space Observatory
(EUSO) will be launched and attached to the Japanese module of the
International Space Station (ISS). Its aim is to observe UV photon tracks
produced by ultra-high energy cosmic rays developing in the atmosphere and
producing extensive air showers.
The key element of the instrument is a very wide-field, very fast,
large-lense telescope that can detect extreme energy particles with energy
above eV. The Atmospheric Monitoring System (AMS), comprising, among
others, the Infrared Camera (IRCAM), which is the Spanish contribution, plays a
fundamental role in the understanding of the atmospheric conditions in the
Field of View (FoV) of the telescope. It is used to detect the temperature of
clouds and to obtain the cloud coverage and cloud top altitude during the
observation period of the JEM-EUSO main instrument. SENER is responsible for
the preliminary design of the Front End Electronics (FEE) of the Infrared
Camera, based on an uncooled microbolometer, and the manufacturing and
verification of the prototype model. This paper describes the flight design
drivers and key factors to achieve the target features, namely, detector
biasing with electrical noise better than V from Hz to MHz,
temperature control of the microbolometer, from C to C
with stability better than mK over hours, low noise high bandwidth
amplifier adaptation of the microbolometer output to differential input before
analog to digital conversion, housekeeping generation, microbolometer control,
and image accumulation for noise reduction
Rectification of Preferences in a Fuzzy Environment.
In this paper we consider a complete fuzzy preference structure, defined by means of a constructive approach associated to the necessary learning process in a decision making problem. Preference relations are successively
assigned over a given set of alternatives with the possibility of revision and rectification, subject to a certain set of beliefs which sustain the construction of
different viewpoints. Measures of information are then considered in this process for a formal identification of uncertainty due to ignorance, a concept that is closely related to ambiguity as defined by Fishburn (1993). Finally, a coherence criterion is proposed in order to study the importance of preferences, in such a way that an indirect and comparative analysis between them is needed so
outcomes may be coherently organized
La Empresariabilidad en Prestadores de Servicios Profesionales Agropecuarios del Estado de Campeche, México
La empresarialidad definida como la capacidad o competencia para generar y crear nuevas iniciativas empresariales tiene su relevancia en el desarrollo territorial y económico. Por lo que los gobiernos estatales buscan apoyar a los productores agropecuarios en el desarrollo de sus competencias empresariales basados en una red de prestadores de servicios profesionales (PSP). El objetivo del artÃculo fue analizar la construcción del concepto de empresarialidad derivado de auto-percepciones (actitudes positivas) y caracterÃsticas de los PSP del medio agropecuario (edad y años como prestadores). Se aplicó un cuestionario con 60 afirmaciones evaluadas en una escala de Likert de 0 a 6, a 105 PSP del estado de Campeche, México; de los que sólo se retuvieron 71 observaciones completas y validas y con las cuales se generó un Ãndice de empresarialidad. El Ãndice se obtuvo como la suma de los valores individuales de cada reactivo, donde 0 era el mÃnimo y 360 el máximo posible (M= 279.23, DS= 35.30, Min= 62, Max= 339). A fin de reducir el número de variables, frases que reflejaban actitudes positivas y que explicaban el Ãndice de empresarialidad, se realizó un análisis factorial obteniéndose 14 constructos, se conservaron dos frases independientes, asà como la edad y el número de años como PSP, para ser utilizados en un análisis de regresión jerárquica. Los resultados muestran que las variables de persistencia, innovación, autoestima, independencia, compromiso, y preferir estar sólo, asà como otras caracterÃsticas están positiva y significativamente asociadas con mayores niveles de empresarialidad (pmenor que0.001), mientras que las variables que no explicaron la misma fueron el riesgo y tomar la iniciativa. La edad y los años de experiencia no estuvieron significativamente asociados con mayores niveles de empresarialidad. Por lo que se concluye que las actitudes positivas son importantes para explicar la autopercepción de empresarialidad, mientras que esta última no depende de la edad de los sujetos. La consecuencia del estudio para los gobiernos estatales radica en fomentar proyectos productivos que impliquen el desarrollo de competencias relacionadas con ser emprendedor, ya que se logran actitudes positivas en los actores locales que repercutirán en una mayor competitividad
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