Search results for "Aves [Birds]"
showing 10 items of 71 documents
Even harmonics generation of high frequency radiation in current-carrying plasmas
2005
Generation of high frequency radiation harmonics in a current-carrying plasma is studied. The physical mechanism responsible for harmonics generation is provided by electron-ion collisions. The current in the plasma is sustained by a constant electric field. It is shown that the electron distribution function anisotropy due to the static field yields generation of even harmonics. As a result, the radiation spectrum emitted by the current-carrying plasma contains both even and odd harmonics, the latter being attributed to currentless plasma. For a broad range of plasma and high frequency radiation parameters, a detailed analysis of the even harmonics properties is reported.
Unusual optical properties of the dense nonequilibrium plasmas
2005
A concise overview of new optical properties of dense nonequilibrium plasma formed on the solid state target boundary is given. In this chapter, we describe phenomena such as the third harmonic generation in the skin layer, collisionless electron heating in the high frequency skin-effect regime, absorption, and reflection and transmission of radiation by a plasma with anisotropic electron distribution.
Limitations of electron cyclotron resonance ion source performances set by kinetic plasma instabilities.
2015
Electron cyclotron resonance ion source (ECRIS) plasmas are prone to kinetic instabilities due to anisotropy of the electron energy distribution function stemming from the resonant nature of the electron heating process. Electron cyclotron plasma instabilities are related to non-linear interaction between plasma waves and energetic electrons resulting to strong microwave emission and a burst of energetic electrons escaping the plasma, and explain the periodic oscillations of the extracted beam currents observed in several laboratories. It is demonstrated with a minimum-B 14 GHz ECRIS operating on helium, oxygen, and argon plasmas that kinetic instabilities restrict the parameter space avail…
Monitoring serologic response to single in ovo vaccination with an immune complex vaccine against infectious bursal disease in broilers
2021
Este artículo se encuentra disponible en la siguiente URL: https://www.sciencedirect.com/science/article/pii/S003257912100033X The infectious bursal disease (IBD) virus is one of the most resistant and prevalent virus worldwide in the poultry industry, being vaccination the main tool to control the disease. For this reason, consistent and uniform immunization of broiler flocks against IBD is necessary to avoid the disease spreading. The aim of this study was to apply and assess an epidemiologic mapping tool focused on the immunization by in ovo single broiler vaccination using an immune complex IBD vaccine. With this regard, 7,576 serum samples were collected from 603 broiler flocks raised …
The lacrimal gland herniation role in the Graves’ orbitopathy
2017
To evaluate the LG involvement, through the measurement of the LG herniation by of magnetic resonance imaging (MRI), in patients with different GO activity
On the interplay between cosmological shock waves and their environment
2017
Cosmological shock waves are tracers of the thermal history of the structures in the Universe. They play a crucial role in redistributing the energy within the cosmic structures and are also amongst the main ingredients of galaxy and galaxy cluster formation. Understanding this important function requires a proper description of the interplay between shocks and the different environments where they can be found. In this paper, an Adaptive Mesh Refinement (AMR) Eulerian cosmological simulation is analysed by means of a shock-finding algorithm that allows to generate shock wave maps. Based on the population of dark matter halos and on the distribution of density contrast in the simulation, we…
Coupling a hydro-maritime model and remotely sensed techniques to assess the shoreline positioning uncertainty: the Marsala coast study case
2010
The severe erosion phenomena affecting the Mediterranean coasts are strictly related to geophysical characteristics and socio-economic pressures. This suggests the need of monitoring and modelling the phenomenon in order to quantify its strength. In fact, the shoreline position, as well as its temporal evolution, provides important information for designing defence structures and for the development of a coastal management plan. The shoreline has a dynamic nature as it changes both in the short and long period. Those changes are caused by geo-morphological (e.g. bars and barrier island development etc.) and hydrodynamic (wave motion, tides and flows) processes, as well as by sudden and fast…
Electrocardiogram Signal Analysing
2016
In this paper, we develop a new approach based on nonlinear filtering scheme (NLFS) on cardiac signal to evaluate a robust single-lead electrocardiogram (ECG) delineation system and waves localization method based on nonlinear filtering approach. This system is built in two phases, in the first phase, we proposed a mathematical model for detecting ECG features like QRS complex peak, P and T-waves onsets and ends fromnoise free of synthetic ECG signal. Later, we develop a theoretical model to obtain real approach for detecting these features from real noisy ECG signals. Our method has been evaluated on electrocardiogram signals of QT-MIT standard database, the QRS peak achieve sensitivity (S…
Sulfuric acid caves of Italy: A review
2019
Abstract In Italy, especially along the Apennine Chain, numerous active and inactive sulfuric acid speleogenetic (SAS) caves have been documented in the last two decades. Here we present an overview of these peculiar hypogene systems, illustrating their main geomorphological and mineralogical features, and the microbial signatures observed in the active underground environment. SAS caves are widely distributed in the northern and central Apennines, whereas they are less abundant in the southern Apennines, in the Apulian foreland, in Sicily and in Sardinia. Their location is significantly influenced by lithological and structural rock properties, as they occur in carbonate areas where acidic…
Mejoras basadas en heurísticas para la percepción de estímulos en simuladores de realidad virtual y realidad aumentada
2023
Los simuladores tratan de hacer creer a los usuarios que están viviendo una situación ajena a su realidad. Habitualmente los sentidos estimulados por los simuladores son el visual, el auditivo y el táctil, este último mediante la instalación de elementos con los que el usuario interactúa, como un volante, un joystick o incluso una cabina de control completa. Otros sentidos, como el olfato, la propiocepción o el vestibular (sentido del movimiento), suelen estimularse menos habitualmente. De todos los sentidos, la presente tesis doctoral se focaliza en el sentido del movimiento. La manera habitual de introducir estímulos de movimiento en usuarios de simuladores es mediante plataformas de movi…