Lethality by pneumonia and factors associated to death

AbstractObjectiveto describe the case-fatality rate (CFR) and risk factors of death in children with community-acquired acute pneumonia (CAP) in a pediatric university hospital.Methoda longitudinal study was developed with prospective data collected from 1996 to 2011. Patients aged 1 month to 12 years were included in the study. Those who left the hospital against medical orders and those transferred to ICU or other units were excluded. Demographic and clinical-etiological characteristics and the initial treatment were studied. Variables associated to death were determined by bivariate and multivariate analysis using logistic regression.Resultsa total of 871 patients were selected, of whom 11 were excluded; thus 860 children were included in the study. There were 26 deaths, with a CFR of 3%; in 58.7% of these, penicillin G was the initial treatment. Pneumococcus was the most common pathogen (50.4%). From 1996 to 2000, there were 24 deaths (93%), with a CFR of 5.8% (24/413). From 2001 to 2011, the age group of hospitalized patients was older (p = 0.03), and the number of deaths (p = 0.02) and the percentage of disease severity were lower (p = 0.06). Only disease severity remained associated to death in the multivariate analysis (OR = 3.2; 95%CI: 1.2-8.9; p = 0.02).Conclusionwhen the 1996-2000 and 2001-2011 periods were compared, a significant reduction in CFR was observed in the latter, as well as a change in the clinical profile of the pediatric inpatients at the institute. These findings may be related to the improvement in the socio-economical status of the population. Penicillin use did not influence CFR

Perturbation evolution with a non-minimally coupled scalar field

We recently proposed a simple dilaton-derived quintessence model in which the scalar field was non-minimally coupled to cold dark matter, but not to `visible' matter. Such couplings can be attributed to the dilaton in the low energy limit of string theory, beyond tree level. In this paper we discuss the implications of such a model on structure formation, looking at its impact on matter perturbations and CMB anisotropies. We find that the model only deviates from $\Lambda$CDM and minimally coupled theories at late times, and is well fitted to current observational data. The signature left by the coupling, when it breaks degeneracy at late times, presents a valuable opportunity to constrain non-minimal couplings given the wealth of new observational data promised in the near future.Comment: Version appearing in Physical Review D. 10 pages, 9 figs. Comparison with SN1a and projected MAP results, and appendix adde

DIAGNÓSTICO AMBIENTAL DO RIO PARAGUAI EM CÁCERES A PARTIR DE INDICADORES MORFOLÓGICOS, PANTANAL SUPERIOR – BRASIL

O objetivo deste estudo foi verificar o nível de degradação do rio Paraguai a partir de indicadores morfológicos e tipologias de uso, no trecho do perímetro urbano de Cáceres – Mato Grosso, bem como nas áreas de influência. Para tanto, os dados foram obtidos através dos Protocolos de Avaliação Rápida de Rios, adaptados de Callisto et al. (2002) e Rodrigues et al. (2012). Para análise granulométrica dos sedimentos adotou-se Embrapa (1997), Suguio (1973), Carvalho (2000) e Leli et al. (2010)

Cosmology with a long range repulsive force

We consider a class of cosmological models in which the universe is filled with a (non-electric) charge density that repels itself by means of a force carried by a vector boson with a tiny mass. When the vector's mass depends upon other fields, the repulsive interaction gives rise to an electromagnetic barrier which prevents these fields from driving the mass to zero. This can modify the cosmology dramatically. We present a very simple realization of this idea in which the vector's mass arises from a scalar field. The electromagnetic barrier prevents this field from rolling down its potential and thereby leads to accelerated expansion.Comment: 15 pages, 8 figures, LaTeX (version accepted for publication in PRD). 3 new figures, extended discussion of observational consequence

Genesis of Dark Energy: Dark Energy as Consequence of Release and Two-stage Tracking Cosmological Nuclear Energy

Recent observations on Type-Ia supernovae and low density ($\Omega_{m} = 0.3$) measurement of matter including dark matter suggest that the present-day universe consists mainly of repulsive-gravity type `exotic matter' with negative-pressure often said `dark energy' ($\Omega_{x} = 0.7$). But the nature of dark energy is mysterious and its puzzling questions, such as why, how, where and when about the dark energy, are intriguing. In the present paper the authors attempt to answer these questions while making an effort to reveal the genesis of dark energy and suggest that `the cosmological nuclear binding energy liberated during primordial nucleo-synthesis remains trapped for a long time and then is released free which manifests itself as dark energy in the universe'. It is also explained why for dark energy the parameter $w = - {2/3}$. Noting that $w = 1$ for stiff matter and $w = {1/3}$ for radiation; $w = - {2/3}$ is for dark energy because $"-1"$ is due to `deficiency of stiff-nuclear-matter' and that this binding energy is ultimately released as `radiation' contributing $"+ {1/3}"$, making $w = -1 + {1/3} = - {2/3}$. When dark energy is released free at $Z = 80$, $w = -{2/3}$. But as on present day at $Z = 0$ when radiation strength has diminished to $\delta \to 0$, $w = -1 + \delta{1/3} = - 1$. This, thus almost solves the dark-energy mystery of negative pressure and repulsive-gravity. The proposed theory makes several estimates /predictions which agree reasonably well with the astrophysical constraints and observations. Though there are many candidate-theories, the proposed model of this paper presents an entirely new approach (cosmological nuclear energy) as a possible candidate for dark energy.Comment: 17 pages, 4 figures, minor correction

Early-universe constraints on a Primordial Scaling Field

In the past years 'quintessence' models have been considered which can produce the accelerated expansion in the universe suggested by recent astronomical observations. One of the key differences between quintessence and a cosmological constant is that the energy density in quintessence, $\Omega_\phi$, could be a significant fraction of the overall energy even in the early universe, while the cosmological constant will be dynamically relevant only at late times. We use standard Big Bang Nucleosynthesis and the observed abundances of primordial nuclides to put constraints on $\Omega_\phi$ at temperatures near $T \sim 1MeV$. We point out that current experimental data does not support the presence of such a field, providing the strong constraint $\Omega_\phi(MeV) < 0.045$ at $2\sigma$ C.L. and strengthening previous results. We also consider the effect a scaling field has on CMB anisotropies using the recent data from Boomerang and DASI, providing the CMB constraint $\Omega_\phi \le 0.39$ at $2\sigma$ during the radiation dominated epoch.Comment: 5 pages, 4 figures. The revised version includes the new Boomerang and DASI dat