983 resultados para Georges Laplace


Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Persistent polyclonal B cell lymphocytosis (PPBL) is a rare condition characterized by increased IgM and large excess of B cells with an IgD(+) CD27(+) phenotype. In normal individuals, these cells play a central role in the defense against pneumococcal infection. So far, few studies have characterized humoral immune responses in PPBL patients. We therefore measured IgG directed against S. pneumoniae antigens in a 51 yr-old woman with PPBL before and after vaccination with a pneumococcal 23-valent polysaccharide vaccine. METHODS: Antibodies against pneumococcal antigens were measured first with an overall immunoassay using microplates coated with the 23-valent pneumococcal vaccine. A serotype-specific test was also performed according to the WHO consensus protocol. RESULTS: Despite a large number of IgD(+) CD27(+) cells, our patient had low baseline titers of IgG directed against pneumococcal antigens and did not significantly respond to a 23-valent polysaccharide vaccine against S. pneumoniae. On the contrary, she had good titers of IgG directed against tetanus toxoid. CONCLUSION: IgM(+) IgD(+) CD27(+) cells which accumulate in this patient with typical PPBL patient failed to perform IgG isotype switch after a polysaccharide vaccine. The potential mechanisms and relationships with the main features of PPBL are discussed. Further studies on a larger number of similar patients are needed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The hydrodynamic structure of an axisymmetric supersonic expansion can be regarded as a series of concentric divergent cones, with decreasing particle densities as the cone angle increases. Different groups of molecules therefore contribute to high-resolution absorption line shapes when optically probing the expansion in a direction perpendicular to the jet axis. These groups are distinguished by the cone angle, inducing a specific Doppler shift, and by the particle density, contributing a specific weight to the absorption intensity. As a result different broader line profiles are observed compared to room temperature spectra. This effect is investigated here selecting as the working example the R(0), ν3 absorption line in N2O recorded using a Fourier transform interferometer. Independent impact pressure and quadrupole mass spectrometric measurements are performed leading to two complementary maps of the expansion, allowing the recorded absorption line shape to be quantitatively modeled. © 2006 Elsevier Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

info:eu-repo/semantics/published

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The topic of this dissertation is the concours pieces for flute at the Paris Conservatory covering two decades. The works are used for exit examination pieces for graduating students at the conservatory. The music is chosen by the director, the professors in the performance area, and a committee of other professors. These pieces still seem to be among the more important pieces known by flutists in the twenty-first century, and they are also frequently used as required audition pieces by conservatories, orchestras, and competitions. I have performed the works used for examination in two decades separated by almost half a century: The pieces from 1900 to 1909 and from 1940-1949, This performance dissertation contains three recital programs, and the recordings of the recitals are filed electronicaIly. I have grouped them according to contrasting styles in three recitals. Works performed are Agrestide (1942) by Eugene Bozza, Andante et Scherzo (1945) by Francois J. Brun, Preude et Scherzo (1908) by Henri Busser, Concertino (1902) by Cecile Chaminade, sixth Solo (1855) by Jules Demersseman (it was on the concours of 1896, dates which are outside the scope of this dissertation), Sonatine (1943) by Henri Dutilleux, Cantabile et Presto (1904) by Georges Enesco, Andante et Scheno (1901) by Louis Ganne, Fantaisie (1920) by Philippe Gaubert, Nocturne et Allegro Scherzando (1906) by Philippe Gaubert, Chant de Linos (1944) by Andre Jolivet, Fantasiestuck (1947) by Henri Martelli, Eglogue (1909) by Jules Mouquet, Concerto in A (1945-1949) by mile Passani, Ballade (1903) by Albert Perhilou, Sonatine (1946) by Pierre Sancan, Andante Pastorale et Scherzettim (1907) by Paul Taffanel, and Concertino in E Major (1945) by Henri Tornasi. Cantabile et Presto was required in both 1904 and 1940, and Andante et Scherzo was required in both 1901 and 1905.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

info:eu-repo/semantics/published

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The authors present 2 cases of AIDS revealed by severe recurrent genital herpes simplex. The patients are 2 young, previously healthy, African women without histories of homosexuality or drug abuse. The first patient died after 5 months of follow-up (post mortem findings: viral bronchopneumonia with positive cultures for herpes and cytomegalovirus (CMV), viral colitis due to CMV). The second patient survived. She has been treated, during the last 11 months, for filariasis, buccal and vaginal candidiasis and cerebral toxoplasmosis.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Photon correlation spectroscopy (PCS) is a light-scattering technique for particle size diagnosis. It has been used mainly in the investigation of hydrosol particles since it is based on the measurement of the correlation function of the light scattered from the Brownian motion of suspended particles. Recently this technique also proved useful for studying soot particles in flames and similar aerosol systems. In the case of a polydispersed system the problem of recovering the particle size distribution can be reduced to the problem of inverting the Laplace transform. In this paper we review several methods introduced by the authors for the solution of this problem. We present some numerical results and we discuss the resolution limits characterizing the reconstruction of the size distributions. © 1989.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

OBJECTIVES: To evaluate the immune reconstitution in HIV-1-infected children in whom highly active antiretroviral therapy (HAART) controlled viral replication and to assess the existence of a relation between the magnitude of this restoration and age. METHODS: All HIV-1-infected children in whom a new HAART decreased plasma viral load below 400 copies/ml after 3 months of therapy were prospectively enrolled in a study of their immune reconstitution. Viral load, lymphocyte phenotyping, determination of CD4+ and CD8+ T cell receptor repertoires and proliferative responses to mitogens and recall antigens were assessed every 3 months during 1 year. RESULTS: Nineteen children were evaluated. Naive and memory CD4+ percentages were already significantly increased after 3 months of HAART. In contrast to memory CD4+ percentages, naive CD4+ percentages continued to rise until 12 months. Age at baseline was inversely correlated with the magnitude of the rise in naive CD4+ cells after 3, 6 and 9 months of therapy but not after 12 months. Although memory and activated CD8+ cells were already decreasing after 3 months, abnormalities of the CD8 T cell receptor repertoire and activation of CD8+ cells persisted at 1 year. HAART increased the response to mitogens as early as 3 months after starting therapy. CONCLUSIONS: In children the recovery of naive CD4+ cells occurs more rapidly if treatment is started at a younger age, but after 1 year of viral replication control, patients of all ages have achieved the same level of restoration. Markers of chronic activation in CD8+ cells persist after 1 year of HAART.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Positive skin prick tests (SPT) for food allergens and specific IgE (sIgE) in serum indicate sensitization but do not enable distinction between sensitized but tolerant and clinically allergic patients. OBJECTIVE: Herein, we evaluate the clinical relevance of basophil activation tests (BATs) for peanut or egg allergy diagnosis. METHODS: Thirty-two peanut-allergic, 14 peanut-sensitized (sIgE(+) and/or SPT(+) to peanuts) but tolerant children and 29 controls with no history of an adverse reaction to peanuts were included. Similarly, 31 egg-allergic, 14 egg-sensitized children (sIgE(+) and/or SPT(+) to egg white) and 22 controls were studied. Flow cytometric analysis of CD63 expression or CD203c upregulation on basophils and the production of leukotrienes (LT) were performed in response to an in vitro crude peanut extract or ovalbumin (OVA) challenge. RESULTS: After in vitro peanut challenge, the basophils from peanut-allergic children showed significantly higher levels of activation than those from controls (P<0.001). After OVA challenge, a similar distinction (P<0.001) was observed between egg-allergics and controls. Interestingly, the majority of egg- or peanut-sensitized children failed to activate basophils, respectively, in response to OVA and peanut challenge. The sensitivity of the CD63, CD203c and LT assay was 86.7%, 89.5% and 76.0% with a specificity of 94.1%, 97.1% and 94.6% for peanut allergy diagnosis. The corresponding performances of BATs applied to egg allergy diagnosis were 88.9%, 62.5% and 77.8% for the sensitivity and 100%, 96.4% and 96.4% for the specificity. CONCLUSION: Neither conventional tests nor BATs are sensitive and specific enough to predict food allergy accurately. However, BATs may helpfully complete conventional tests, especially SPT, allowing improved discrimination between allergic and non-allergic individuals.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

info:eu-repo/semantics/published

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper was selected by the editors of the Journal of Chemical Physics as one of the few of the many notable JCP articles published in 2009 that present ground-breaking research

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Un poco de historia. Los cálculos eran la preocupación principal de nuestros antepasados, que promovieron el desarrollo de las matemáticas. Así nacieron los logaritmos, en los últimos años del siglo XVII. Decía Laplace en aquello años, “el uso de los logaritmos, acortó el trabajo y duplicó la vida de los astrónomos”. En los últimos años de la década 1970 a 1980 se popularizaron las calculadoras. Que no son tan viejas. Yo, no las use. En 1972 entre a la facultad de química y no tenía calculadora. Un año antes, me compre una de las mejores reglas de cálculo. Para usarla deberíamos saber tanto, que nos calificarían de genio en la actualidad ¿Cuál es entonces la premisa de mi pensamiento? “Saber matemática no es saber hacer cuentas”

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A 3D model of melt pool created by a moving arc type heat sources has been developed. The model solves the equations of turbulent fluid flow, heat transfer and electromagnetic field to demonstrate the flow behaviour phase-change in the pool. The coupled effects of buoyancy, capillary (Marangoni) and electromagnetic (Lorentz) forces are included within an unstructured finite volume mesh environment. The movement of the welding arc along the workpiece is accomplished via a moving co-ordinator system. Additionally a method enabling movement of the weld pool surface by fluid convection is presented whereby the mesh in the liquid region is allowed to move through a free surface. The surface grid lines move to restore equilibrium at the end of each computational time step and interior grid points then adjust following the solution of a Laplace equation.