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ESTADO NUTRICIONAL EN LACTANTES Y PREESCOLARES, DEL AMBULATORIO “DR. J. M. VARGAS” BARQUISIMETO, LARA.
Figueredo-Lapi, Víctor,Albano, Giuseppe,Araujo Cristóbal,Torres María
Salud, Arte y Cuidado , 2012,
Abstract: The purpose was to determine the nutritional status of the infants and children under six years old in the area of the type I ambulatory “Dr. José Maria Vargas” located in Veragacha, Irribarren county, Barquisimeto. A descriptive study was conducted in a nonprobabilisticsample of one hundred and three (103) kids from 1 month to 6 years old. A questionnaire was applied to the mothers and structured in: age, sex, socio-economic status and anthropometric data (height and weight). The anthropometric data was taken to the OMS’s tables and was interpreted according to the combination of indicators: eight/age,weight/height and height/age. The analysis showed the following results: According to the total of the sample: 66.0% presented normal nutritional status; 8.7% current malnutrition;6.8% low stature and 8.7% excess malnutrition. Most of children belonged to the stratum IV(77.0%) and was appreciated an increment of malnutrition in the lower stratums. There was no statistical signi cant difference between the variables under investigation. This work Decanato de Ciencias de la Salud. Universidad Centroccidental “Lisandro Alvarado” (UCLA)expects to stimulate the development of plans and programs that improve the nutritional status of the children in the area, the detection and the early correction of the current risk factors.
REPORTE DE UN CASO DE ATRIQUIA CONGéNITA CON LESIONES PAPULARES
Figueredo Lapi, Víctor,Torrealba Fajardo, Maria,Estrada, Pedro
Salud, Arte y Cuidado , 2012,
Abstract: The congenital atriquia with papular lesions is a rare genetic disorder of alopecia with a surprisingly low frequency. It is caused by mutation in the hairless gene of chromosome 8p12 with an autosomal recessive pattern. Reported a case of female patient, a 36-years-oldwoman was referred to the of ce of Medical Genetics in the Faculty of Health Sciences at the University Centrocciodental “Lisandro Alvarado”. The woman presented alopecia and papular lesions. The ndings are discussed, the literature is reviewed, and patient’scharacteristics are compared with those found in other cases. The diagnosis is congenital atriquia with papular lesions.
La difficile posizione giuridica dei Testimoni di Geova in Russia di fronte alla Corte di Strasburgo
Chiara Lapi
Stato, Chiese e Pluralismo Confessionale , 2011,
Abstract: Contributo segnalato dal Prof. Pierluigi Consorti che ne ha attestato l'originalità e la scientificità. SOMMARIO: 1. Il fatto - 2. Il ruolo dei Testimoni di Geova e delle altre religioni in Russia dal 1891 ad oggi - 3. Il merito - 4. Conclusioni.
Dark Matter Halos: The Dynamical Basis of Effective Empirical Models
Andrea Lapi,Alfonso Cavaliere
Advances in Astronomy , 2011, DOI: 10.1155/2011/903429
Abstract: We investigate the dynamical basis of the classic empirical models (specifically, Sérsic-Einasto and generalized NFW) that are widely used to describe the distributions of collisionless matter in galaxies. We submit that such a basis is provided by our -profiles, shown to constitute solutions of the Jeans dynamical equilibrium with physical boundary conditions. We show how to set the parameters of the empirical in terms of the dynamical models; we find the empirical models, and specifically Sérsic-Einasto, to constitute a simple and close approximation to the dynamical models. Finally, we discuss how these provide a useful baseline for assessing the impact of the small-scale dynamics that may modulate the density slope in the central galaxy regions. 1. Introduction The classic Sérsic [1] models met a wide and lasting success as empirical representations of the projected ( -dimensional) light distributions in spheroidal galaxies (for a review, see Kormendy et al. [2]). Einasto [3] developed and used a similar shape to describe in simple terms -dimensional stellar mass profiles. On the other hand, recent extensive -body simulations (e.g., [4–8]) indicate that the Sérsic and Einasto functional forms also provide good patterns to represent the spherically-averaged mass distributions in dark matter (DM) halos ranging from galaxies to galaxy clusters. These hold at levels comparable to, or even better than the popular NFW formula [9]. Still, no agreed understanding is available to explain the value in both the real and the virtual worlds of the Sérsic and Einasto representations (see [2, 10]). Can we identify the underlying astrophysical basis? 2. Empirical Models Before addressing the issue, we note that these models belong to two main families: generalized NFW (see [11–13]; hereafter gNFW) and Sérsic-Einasto (see [10, 14, 15]; hereafter SE). 2.1. Density Runs The density runs of the SE family may be represented in the form Here, quantities are normalized to their value at , the reference radius where the logarithmic slope takes on the value ; typically, in nearby elliptical galaxies, corresponds to sizes of order ?kpc, a few times the half-light radius . The parameters and describe the inner slope and the middle curvature of the density run, respectively. The original Einasto profile belongs to this family and is obtained when . Note, however, that by deprojecting from the plane of the sky, a Sérsic -dimensional run with index (suited for normal ellipticals, see [2]) produces a cuspy inner run as in (1) with significantly different from and less than , as
Structure and History of Dark Matter Halos Probed with Gravitational Lensing
A. Lapi,A. Cavaliere
Physics , 2009, DOI: 10.1088/0004-637X/695/2/L125
Abstract: We test with gravitational lensing data the dark matter (DM) halos embedding the luminous baryonic component of galaxy clusters; our benchmark is provided by their two-stage cosmogonical development that we compute with its variance, and by the related '\alpha-profiles' we derive. The latter solve the Jeans equation for the self-gravitating, anisotropic DM equilibria, and yield the radial runs of the density \rho(r) and the velocity dispersion \sigma_r^2(r) in terms of the DM 'entropy' K = \sigma_r^2/\rho^(2/3) ~ r^(\alpha) highlighted by recent N-body simulations; the former constrains the slope to the narrow range \alpha ~ 1.25 - 1.3. These physically based \alpha-profiles meet the overall requirements from gravitational lensing observations, being intrinsically flatter at the center and steeper in the outskirts relative to the empirical NFW formula. Specifically, we project them along the l.o.s. and compare with a recent extensive dataset from strong and weak lensing observations in and around the cluster A1689. We find an optimal fit at both small and large scales in terms of a halo constituted by an early body with \alpha ~ 1.25 and by recent extensive outskirts, that make up an overall mass 10^15 M_sun with a concentration parameter c ~ 10 consistent with the variance we compute in the \LambdaCDM cosmogony. The resulting structure corresponds to a potential well shallow in the outskirts as that inferred from the X rays radiated from the hot electrons and baryons constituting the intracluster plasma.
Statistics of Dark Matter Halos in the Excursion Set Peak Framework
A. Lapi,L. Danese
Physics , 2014, DOI: 10.1088/1475-7516/2014/07/044
Abstract: We derive approximated, yet very accurate analytical expressions for the abundance and clustering properties of dark matter halos in the excursion set peak framework; the latter relies on the standard excursion set approach, but also includes the effects of a realistic filtering of the density field, a mass-dependent threshold for collapse, and the prescription from peak theory that halos tend to form around density maxima. We find that our approximations work excellently for diverse power spectra, collapse thresholds and density filters. Moreover, when adopting a cold dark matter power spectra, a tophat filtering and a mass-dependent collapse threshold (supplemented with conceivable scatter), our approximated halo mass function and halo bias represent very well the outcomes of cosmological $N-$body simulations.
Dark Matter Halos: The Dynamical Basis of Effective Empirical Models
A. Lapi,A. Cavaliere
Physics , 2010,
Abstract: We investigate the dynamical basis of the classic empirical models (specifically, Sersic-Einasto and generalized NFW) that are widely used to describe the distributions of collisionless matter in galaxies. We submit that such a basis is provided by our \alpha-profiles, shown to constitute solutions of the Jeans dynamical equilibrium with physical boundary conditions. We show how to set the parameters of the empirical in terms of the dynamical models; we find the empirical models, and specifically Sersic-Einasto, to constitute a simple and close approximation to the dynamical models. Finally, we discuss how these provide an useful baseline for assessing the impact of the small-scale dynamics that may modulate the density slope in the central galaxy regions.
Self-Similar Dynamical Relaxation of Dark Matter Halos in an Expanding Universe
A. Lapi,A. Cavaliere
Physics , 2011, DOI: 10.1088/0004-637X/743/2/127
Abstract: We investigate the structure of cold dark matter halos using advanced models of spherical collapse and accretion in an expanding Universe. These base on solving time-dependent equations for the moments of the phase-space distribution function in the fluid approximation; our approach includes non-radial random motions, and most importantly, an advanced treatment of both dynamical relaxation effects that takes place in the infalling matter: phase-mixing associated to shell crossing, and collective collisions related to physical clumpiness. We find self-similar solutions for the spherically-averaged profiles of mass density rho(r), pseudo phase-space density Q(r) and anisotropy parameter beta(r). These profiles agree with the outcomes of state-of-the-art N-body simulations in the radial range currently probed by the latter; at smaller radii, we provide specific predictions. In the perspective provided by our self-similar solutions we link the halo structure to its two-stage growth history, and propose the following picture. During the early fast collapse of the inner region dominated by a few merging clumps, efficient dynamical relaxation plays a key role in producing a closely universal mass density and pseudo phase-space density profiles; in particular, these are found to depend only weakly on the detailed shape of the initial perturbation and the related collapse times. The subsequent inside-out growth of the outer regions feeds on the slow accretion of many small clumps and diffuse matter; thus the outskirts are only mildly affected by dynamical relaxation but are more sensitive to asymmetries and cosmological variance.
The Astrophysics of the Intracluster Plasma
A. Cavaliere,A. Lapi
Physics , 2013, DOI: 10.1016/j.physrep.2013.08.001
Abstract: [Abridged] Since 1971 observations in X rays of thousands galaxy clusters have uncovered huge amounts of hot baryons filling up the deep gravitational potential wells provided by dark matter (DM) halos with sizes of millions light-years and masses of some 10^15 M_sun. At temperatures T~10^8 K and with average densities of n~1 particle per liter, such baryons add up to some 10^14 M_sun. With the neutralizing electrons, they constitute the best proton-electron plasma in the Universe (Intra Cluster Plasma, ICP). A key physical feature of the ICP is constituted by its good local Thermal equilibrium, and by its overall hydrostatic condition in the DM wells, modulated by entropy. The latter is set up in the cluster center by the initial halo collapse, and is progressively added at the outgrowing cluster boundary by standing shocks in the supersonic flow of intergalactic gas into the DM wells. We review these entropy-based models and discuss their outcomes and predictions concerning the ICP observables in X rays and in microwaves. The results provide a baseline for disentangling a number of additional and intriguing physical processes superposed to the general equilibrium. We cover: the central entropy erosion produced by radiative cooling vs. the intermittent energy inputs mainly due to active galactic nuclei and mergers; outer turbulent support linked with weakening shocks and decreasing inflow through the virial boundary, causing reduced entropy production; the development from high to low entropy levels throughout a typical cluster; perturbations of the equilibrium up to outright disruption due to deep impacts of infalling galaxy groups or collisions with comparable companion clusters; relativistic energy distributions of electrons accelerated during such events, producing extended radio emission by synchrotron radiation, and contributing to non-thermal pressure support for the ICP.
Los colegios invisibles
E. Figueredo
Revista de la Sociedad Espa?ola del Dolor , 2004,
Abstract:
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