QED vacuum between an unusual pair of plates

We consider the photon field between an unusual configuration of infinite parallel plates: a perfectly conducting plate $(\epsilon\to\infty)$ and an infinitely permeable one $\mu\to\infty)$. After quantizing the vector potential in the Coulomb gauge, we obtain explicit expressions for the vacuum expectation values of field operators of the form $_0$ and $<{\hat B}_i{\hat B}_j>_0$. These field correlators allow us to reobtain the Casimir effect for this set up and to discuss the light velocity shift caused by the presence of plates (Scharnhorst effect \cite{Scharnhorst,Barton,BarScharn}) for both scalar and spinor QED.Comment: Latex, 16 pages, no figure

In-Hospital and Long-Term Prognosis after Spontaneous Intracerebral Hemorrhage among Young Adults Aged 18-65 Years

BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) accounts for 10%-15% of all strokes and has an estimated annual incidence of 5/100,000 in young adults. Limited data on prognosis after ICH in young adults are available. We aimed to identify prognostic predictors after ICH among adults aged 18-65 years. METHODS: We retrospectively selected all patients with ICH from a prospective single-center registry of adults with first stroke before 65 years between 1997 and 2002. We recorded in-hospital mortality as well as mortality and recurrent stroke after discharge until December 1, 2018. For in-hospital analysis, we compared patients that died in-hospital versus patients discharged alive. For long-term analysis, we compared patients that died in follow-up versus patients still alive. Independent prognostic predictors were identified using multivariate analyses. RESULTS: Among 161 patients included, 24 (14.9%) died in-hospital. Among in-hospital survivors, 5-year survival was 92.0%, 10-year survival 78.1%, and 15-year survival 62.0%. After median follow-up of 17 years, 47.4% of patients died, 18 patients had ischemic stroke, and 6 recurrent ICH. Regarding in-hospital prognosis, coma at admission (OR .02 [.00-.11]) was independent predictor for mortality whereas alcoholic habits (OR 12.32 [1.82-83.30]) was independent predictor for survival. An increasing age (OR 1.08 [1.03-1.12]), higher blood glucose levels (OR 1.01 [1.00-1.01]), and hypertension (OR 2.21 [1.22-4.00]) were independent predictors of long-term mortality after ICH. CONCLUSIONS: Alcoholic habits may influence in-hospital survival after ICH in young adults. Long-term mortality in young adults seems to be lower than in elderly and was predicted by higher blood glucose levels and hypertension.info:eu-repo/semantics/publishedVersio

Quantum Cosmology in Scalar-Tensor Theories With Non Minimal Coupling

Quantization in the minisuperspace of non minimal scalar-tensor theories leads to a partial differential equation which is non separable. Through a conformal transformation we can recast the Wheeler-DeWitt equation in an integrable form, which corresponds to the minimal coupling case, whose general solution is known. Performing the inverse conformal transformation in the solution so found, we can construct the corresponding one in the original frame. This procedure can also be employed with the bohmian trajectories. In this way, we can study the classical limit of some solutions of this quantum model. While the classical limit of these solutions occurs for small scale factors in the Einstein's frame, it happens for small values of the scalar field non minimally coupled to gravity in the Jordan's frame, which includes large scale factors.Comment: latex, 18 page

Report on advances for pediatricians in 2018: allergy, cardiology, critical care, endocrinology, hereditary metabolic diseases, gastroenterology, infectious diseases, neonatology, nutrition, respiratory tract disorders and surgery.

This review reported notable advances in pediatrics that have been published in 2018. We have highlighted progresses in allergy, cardiology, critical care, endocrinology, hereditary metabolic diseases, gastroenterology, infectious diseases, neonatology, nutrition, respiratory tract disorders and surgery. Many studies have informed on epidemiologic observations. Promising outcomes in prevention, diagnosis and treatment have been reported. We think that advances realized in 2018 can now be utilized to ameliorate patient car

Avaliação da atividade celulolítica de agentes de controle biológico.

In: CONGRESSO BRASILEIRO DE DEFENSIVOS AGRÍCOLAS NATURAIS, 5., 2011, Jaguariúna. Anais... Jaguariúna: Embrapa Meio Ambiente, 2011. 1 CD ROM

Quantum Cosmological Perturbations of Generic Fluids in Quantum Universes

In previous works, it was shown that the Lagrangians and Hamiltonians of cosmological linear scalar, vector and tensor perturbations of homogeneous and isotropic space-times with flat spatial sections containing a perfect fluid can be put in a simple form through the implementation of canonical transformations and redefinitions of the lapse function, without ever using the background classical equations of motion. In this paper, we generalize this result to general fluids, which includes entropy perturbations, and to arbitrary spacelike hyper-surfaces through a new method together with the Faddeev-Jackiw procedure for the constraint reduction. A simple second order Hamiltonian involving the Mukhanov-Sasaki variable is obtained, again without ever using the background equations of motion.Comment: 19 pages, revtex4-1, submitted to PRD, expanded discussion about our method, fixed typo