2,731 research outputs found
Atmospheric muon background in the ANTARES detector
An evaluation of the background due to atmospheric muons in the ANTARES high
energy neutrino telescope is presented. Two different codes for atmospheric
shower simulation have been used. Results from comparisons between these codes
at sea level and detector level are presented. The first results on the
capability of ANTARES to reject this class of background are given.Comment: 4 pages, 4 figures, To appear in Proceedings of the 29th
International Cosmic Ray Conference (ICRC 2005), Pune, India, 3 - 10 Aug 200
Nuclear Track Detectors for Environmental Studies and Radiation Monitoring
Several improvements were made for Nuclear Track Detectors (NTDs) used for
environmental studies and for particle searches. A new method was used to
determine the bulk etch rate of CR39 and Makrofol NTDs. It is based on the
simultaneous measurement of the diameter and of the height of etch-pit cones
caused by relativistic heavy ions (158 A GeV Pb(82+) and In(49+) ions) and
their fragments. The use of alcohol in the etching solution improves the
surface quality of NTDs and it raises their thresholds. The detectors were used
for the determination of nuclear fragmentation cross sections of Iron and
Silicon ions of 1.0 and 0.41 GeV/nucleon. These measurements are important for
the determination of doses in hadron therapy and for doses received by
astronauts. The detectors were also used in the search of massive particles in
the cosmic radiation, for the determination of the mass spectrum of cosmic rays
and for the evaluation of Po(210) alpha decay and of natural radon
concentrations.Comment: 7 pages, 5 EPS figures. Presented at the 10th Topical Seminar on
Innovative Particle and Radiation Detectors, 1-5 October 2006, Siena, Ital
Water oxygenation and sea bass
The influence of water oxygen concentration on the acid–base balance of sea bass was evaluated. Fish weighing 200–250 g were cultured under different dissolved oxygen concentrations of 64%, 97%, 150% and 250% saturation (92.7, 140.5, 217.5 and 362.7 mmHg respectively) under mild hypoxia, normoxia, mild hyperoxia and high hyperoxia conditions. The results showed that high hyperoxia and mild hypoxia conditions modified some blood parameters significantly when compared with fish held under the normoxia condition, while no differences were shown with respect to the acid–base balance of fish cultured under normoxia and mild hyperoxia conditions. This testifies that the mild hyperoxia condition does not produce physiological disturbances in the acid–base status of sea bass and it could be considered a favourable condition in sea bass land-based farming, mainly in comparison with the mild hypoxia condition, responsible for other physiological problems
Bulk Etch Rate Measurements and Calibrations of Plastic Nuclear Track Detectors
New calibrations of CR39 and Makrofol nuclear track detectors have been
obtained using 158 A GeV Pb (82+) and In (49+) ions; a new method for the bulk
etch rate determination, using both cone height and base diameter measurements
was developed. The CR39 charge resolution based on the etch-pit base area
measurement is adequate to identify nuclear fragments in the interval 7 <=
Z/beta <= 49. For CR39 the detection threshold is at REL~50 MeV cm^2/g,
corresponding to a nuclear fragment with Z/beta~7. Base cone area distributions
for Makrofol foils exposed to Pb (82+) ions have shown for the first time all
peaks due to nuclear fragments with Z > 50; the distribution of the etched cone
heights shows well separated individual peaks for Z/beta = 78 - 83 (charge
pickup). The Makrofol detection threshold is at REL 2700 MeV cm^2/g,
corresponding to a nuclear fragment with Z/beta~50.Comment: 11 pages, 5 EPS figures. Submitted to Nucl. Instr. Meth.
The energy-oriented management of public historic buildings: An integrated approach and methodology applications
In the European framework, there is a strong drive to develop integrated approaches aimed at understanding and improving the energy behavior of public historic buildings within urban contexts. However, the examples already provided tend to address the issue from mono-disciplinary perspectives, losing the opportunity for a coordinated view. The research suggests a methodology to reach the definition of a three-dimensional database, which incorporates spatial models and energy information, with the final goal of merging heterogeneous information that is useful to interpret the overall framework and to design sustainable development scenarios. The platform achieves GIS (Geographic Information System) and BIM (Building Information Modeling) integration by using the CityGML data model, for supporting multi-scale analyses without break of continuity, ranging from urban to building level. The discussion combines the applicative case with the theoretical background, deepening the role of a solid knowledge framework as a basis for sustainable interventions on public historic buildings. To better explain and test the methodology, a case study on the University built heritage of Pavia is presented and three possible outputs deriving from the database are discussed. The example demonstrates the strength of the approach, which is able to provide a variety of results coming from a unique source of information, ensuring coherence and unambiguousness at all levels of investigation
Evaluation of metaperception of goal orientation and moral functioning in soccer spectators
La violencia en el fútbol es un grave problema social. Algunas de sus
manifestaciones están relacionadas con el espectáculo deportivo y su
tratamiento en los medios de comunicación. La finalidad de este estudio ha sido
analizar las propiedades psicométricas de dos escalas en español que miden la
meta-percepción de orientación de meta y el funcionamiento moral en
espectadores de fútbol. Los participantes fueron estudiantes universitarios (N =
616) que completaron cuestionarios valorando el tiempo dedicado al consumo
de programas deportivos sobre fútbol, la meta-percepción de orientación de meta
y el funcionamiento moral. Las escalas definitivas mostraron una adecuada
validez de constructo, validez convergente y validez concurrente. Estos
resultados indican que las nuevas escalas poseen adecuadas propiedades
psicométricas, lo que permite una evaluación válida y fiable que mejore el entendimiento de los procesos que operan en los espectadores de deportes como el fútbolSoccer violence is a serious social problem. Some of its manifestations are
related to competitive sport and its treatment by the mass media. The purpose
of this study was to analyze the psychometric properties of two Spanish scales
which measure the metaperception of goal orientation and moral functioning in
soccer spectators. Participants (N = 616) reported the time spent viewing
soccer sport programming, and rated metaperception of goal orientation and
moral functioning. The scales exhibited adequate construct, convergent and
concurrent validity. These results indicate that the new scales have adequate
psychometric properties, allowing a valid and reliable assessment in order to
explain the processes that take place in sport spectators like soccer viewer
Allosteric Communication in Myosin V: From Small Conformational Changes to Large Directed Movements
The rigor to post-rigor transition in myosin, a consequence of ATP binding, plays an essential role in the Lymn–Taylor functional cycle because it results in the dissociation of the actomyosin complex after the powerstroke. On the basis of the X-ray structures of myosin V, we have developed a new normal mode superposition model for the transition path between the two states. Rigid-body motions of the various subdomains and specific residues at the subdomain interfaces are key elements in the transition. The allosteric communication between the nucleotide binding site and the U50/L50 cleft is shown to result from local changes due to ATP binding, which induce large amplitude motions that are encoded in the structure of the protein. The triggering event is the change in the interaction of switch I and the P-loop, which is stabilized by ATP binding. The motion of switch I, which is a relatively rigid element of the U50 subdomain, leads directly to a partial opening of the U50/L50 cleft; the latter is expected to weaken the binding of myosin to actin. The calculated transition path demonstrates the nature of the subdomain coupling and offers an explanation for the mutual exclusion of ATP and actin binding. The mechanism of the uncoupling of the converter from the motor head, an essential part of the transition, is elucidated. The origin of the partial untwisting of the central β-sheet in the rigor to post-rigor transition is described
Data Fusion Techniques for Processing Aerospace Remote Sensing Electro-Optical Data
This paper deals with data fusion between different resolution multispectral (MS) and panchromatic (Pan) images in order to obtain high spatial resolution MS images. A survey is provided about the state-of-the-art data fusion techniques and synthesized product's quality assessment criteria. Several fusion algorithms and quality indexes were implemented in a Toolbox with a graphical user interface developed in MATLAB environment, namely Fusion Tool Box (FTB), developed to obtain experimental results. The analysis performed through FTB on two different data sets was oriented to validate the theoretical analysis and to perform a quantitative comparison among fusion algorithms for several applications. Results allow a first level evaluation of advantages and drawbacks of the various techniques for specific applications
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