Search results for "Node"
showing 10 items of 1701 documents
Oral lesions in HIV positive AIDS adolescents perinatally infected undergoing HAART
2010
Objective: To assess the prevalence of the oral lesions related to HIV-infection (HIV-OL) in HIV+/AIDS adolescents (=13 years old), and the differences with HIV+/AIDS children (=3 - 0.05). Oral candidiasis was the most prevalent oral lesion in both groups. Association (p <0.05) of a high prevalence of HIV-OL and oral candidiasis with a high viral load was observed in both study groups. Conclusions: Adolescents perinatally HIV-infected have a high prevalence of HIV-OL. Oral candidiasis still is the most frequent oral opportunistic infection. Oral lesions could have association to viral failure in HIV+/AIDS adolescents undergoing HAART
Determinants of HIV outpatient service utilization according to HIV parameters
2014
Introduction : The increased life expectancy of HIV patients in the era of highly active antiretroviral therapy has had profound consequences for the healthcare systems that provide their care. It is useful to assess whether healthcare resources need to be adapted to the different stages of HIV infection or to patient characteristics [1]. To study how patient features influence utilization of out patient services, we retrospectively analyzed the electronic health record of HIV-positive patients who had followed day-care programs at the AIDS Center of the University of Palermo, Italy. Materials and Methods : 223 HIV-infected subjects were recruited and divided into two groups according to CD…
270 Increased hospital mortality in HIV-infected patients with acute coronary or cerebrovascular syndromes. Analysis from a French nationwide hospita…
2011
Background After more than two decades of the AIDS epidemic, the spectrum of HIV-associated vascular diseases has considerably evolved from infectious disease with improved survival, to premature atherosclerosis. As a consequence, acute atherosclerosis complications, such as acute coronary and cerebrovascular syndromes (ACS and CVS) are currently growing. However, only few data are available on HIV-infected patients in the setting of ACS/CVS. The aim of the present study was to determine the prevalence of HIV, as well as the characteristics and hospital case fatality of HIV-infected patients with CVS and ACS. Methods From the French nationwide hospital medical information database, data fro…
Factors Associated with Nonsuppression of HIV Infection in the Spanish VACH Cohort.
2020
We aim to determine the prevalence of HIV nonsuppression and factors associated with it. This is a cross-sectional multicenter study carried out in January 2016 with data of the VACH Cohort, a registry participated by 23 hospitals from most regions of Spain. The prevalence of HIV nonsuppression, defined as HIV RNA ≥200 copies/mL, is documented. The possible association of HIV nonsuppression with sociodemographic and clinical variables is assessed with a logistic regression analysis. A total of 30,843 adult patients are included; 7,358 of them (23.86%) have nonsuppressed HIV. An association is found between nonsuppression of HIV and the following variables: lower body mass index, lower age o…
Stroke in the young in sicily: Prevalence and clinical features
1998
Few epidemiological reports focus on the prevalence of stroke in the young population. As part of a neuroepidemiological survey on the total population of three Sicilian municipalities, we assessed the prevalence of stroke in the young, describing the clinical features of each patient. We screened 14,832 subjects younger than 40 years with a door-to-door method and a two-phase study design. Phase 1 consisted of a questionnaire and a brief neurological examination; phase 2 was an extensive evaluation performed by a neurologist. On the prevalence day (November 1, 1987), we ascertained six cases of stroke (prevalence rate, 40.5/100,000). Three were hemorrhagic, one ischemic, and two of uncerta…
Remarks on the economic interpretation of Hopf bifurcations
1999
Abstract The Hopf bifurcation theorem has become a frequently used tool in the study of nonlinear dynamical economic systems. In this paper, it is shown that phenomena like multiple limit cycles, hysteresis loops and catastrophic transitions may possibly accompany a Hopf bifurcation. The theoretical argument is illustrated in Foley's liquidity cost–business cycle model.
Coexistence of periods in a bifurcation
2012
Abstract A particular type of order-to-chaos transition mediated by an infinite set of coexisting neutrally stable limit cycles of different periods is studied in the Varley–Gradwell–Hassell population model. We prove by an algebraic method that this kind of transition can only happen for a particular bifurcation parameter value. Previous results on the structure of the attractor at the transition point are here simplified and extended.
A SUBCRITICAL BIFURCATION FOR A NONLINEAR REACTION–DIFFUSION SYSTEM
2010
In this paper the mechanism of pattern formation for a reaction-diffusion system with nonlinear diffusion terms is investigated. Through a linear stability analysis we show that the cross-diffusion term allows the pattern formation. To predict the form and the amplitude of the pattern we perform a weakly nonlinear analysis. In the supercritical case the Stuart-Landau equation is found, which rules the evolution of the amplitude of the most unstable mode. With the increasing distance from the bifurcation value of the cross-diffusion parameter, the weakly nonlinear analysis fails and a Fourier–Galerkin approach is adopted. In the subcritical case the weakly nonlinear analysis must be pushed u…
Transitions in a stratified Kolmogorov flow
2016
We study the Kolmogorov flow with weak stratification. We consider a stabilizing uniform temperature gradient and examine the transitions leading the flow to chaotic states. By solving the equations numerically we construct the bifurcation diagram describing how the Kolmogorov flow, through a sequence of transitions, passes from its laminar solution toward weakly chaotic states. We consider the case when the Richardson number (measure of the intensity of the temperature gradient) is $$Ri=10^{-5}$$ , and restrict our analysis to the range $$0<Re<30$$ . The effect of the stabilizing temperature is to shift bifurcation points and to reduce the region of existence of stable drifting states. The…
The period function of reversible quadratic centers
2006
Abstract In this paper we investigate the bifurcation diagram of the period function associated to a family of reversible quadratic centers, namely the dehomogenized Loud's systems. The local bifurcation diagram of the period function at the center is fully understood using the results of Chicone and Jacobs [C. Chicone, M. Jacobs, Bifurcation of critical periods for plane vector fields, Trans. Amer. Math. Soc. 312 (1989) 433–486]. Most of the present paper deals with the local bifurcation diagram at the polycycle that bounds the period annulus of the center. The techniques that we use here are different from the ones in [C. Chicone, M. Jacobs, Bifurcation of critical periods for plane vecto…