Probing pre-formed alpha particles in the ground state of nuclei

In this Letter, we report on alpha particle emission through the nuclear break-up in the reaction 40Ca on a 40Ca target at 50A MeV. It is observed that, similarly to nucleons, alpha particles can be emitted to the continuum with very specific angular distribution during the reaction. The alpha particle properties can be understood as resulting from an alpha cluster in the daughter nucleus that is perturbed by the short range nuclear attraction of the collision partner and emitted. A time-dependent theory that describe the alpha particle wave-function evolution is able to reproduce qualitatively the observed angular distribution. This mechanism offers new possibilities to study alpha particle properties in the nuclear medium.Comment: 4 pages, 3 figure

Probing the 6He halo structure with elastic and inelastic proton scattering

Proton elastic scattering and inelastic scattering to the first excited state of 6He have been measured over a wide angular range using a 40.9A MeV 6He beam. The data have been analyzed with a fully microscopic model of proton-nucleus scattering using 6He wave functions generated from large space shell model calculations. The inelastic scattering data show a remarkable sensitivity to the halo structure of 6He.Comment: 9 pages, 3 figures. RevTeX. Replaced figure 3 with updated figur

Determinants of human adipose tissue gene expression: impact of diet, sex, metabolic status, and cis genetic regulation

Weight control diets favorably affect parameters of the metabolic syndrome and delay the onset of diabetic complications. The adaptations occurring in adipose tissue (AT) are likely to have a profound impact on the whole body response as AT is a key target of dietary intervention. Identification of environmental and individual factors controlling AT adaptation is therefore essential. Here, expression of 271 transcripts, selected for regulation according to obesity and weight changes, was determined in 515 individuals before, after 8-week low-calorie diet-induced weight loss, and after 26-week ad libitum weight maintenance diets. For 175 genes, opposite regulation was observed during calorie restriction and weight maintenance phases, independently of variations in body weight. Metabolism and immunity genes showed inverse profiles. During the dietary intervention, network-based analyses revealed strong interconnection between expression of genes involved in de novo lipogenesis and components of the metabolic syndrome. Sex had a marked influence on AT expression of 88 transcripts, which persisted during the entire dietary intervention and after control for fat mass. In women, the influence of body mass index on expression of a subset of genes persisted during the dietary intervention. Twenty-two genes revealed a metabolic syndrome signature common to men and women. Genetic control of AT gene expression by cis signals was observed for 46 genes. Dietary intervention, sex, and cis genetic variants independently controlled AT gene expression. These analyses help understanding the relative importance of environmental and individual factors that control the expression of human AT genes and therefore may foster strategies aimed at improving AT function in metabolic diseases

Inverse kinematics proton scattering from the exotic nucleus 22^{22}O

NESTER PTHInternational audienceWe have measured for the first time elastic and inelastic proton scattering from the neutron rich nucleus 22O at 46.6 AMeV using the MUST array

Structure of exotic nuclei from direct reactions

Expérience GANILInternational audienc

Adipose tissue transcriptome reflects variations between subjects with continued weight loss and subjects regaining weight 6 mo after caloric restriction independent of energy intake

BACKGROUND: The mechanisms underlying body weight evolution after diet-induced weight loss are poorly understood. OBJECTIVE: We aimed to identify and characterize differences in the subcutaneous adipose tissue (SAT) transcriptome of subjects with different weight changes after energy restriction-induced weight loss during 6 mo on 4 different diets. DESIGN: After an 8-wk low-calorie diet (800 kcal/d), we randomly assigned weight-reduced obese subjects from 8 European countries to receive 4 diets that differed in protein and glycemic index content. In addition to anthropometric and plasma markers, SAT biopsies were taken at the beginning [clinical investigation day (CID) 2] and end (CID3) of the weight follow-up period. Microarray analysis was used to define SAT gene expression profiles at CID2 and CID3 in 22 women with continued weight loss (successful group) and in 22 women with weight regain (unsuccessful group) across the 4 dietary arms. RESULTS: Differences in SAT gene expression patterns between successful and unsuccessful groups were mainly due to weight variations rather than to differences in dietary macronutrient content. An analysis of covariance with total energy intake as a covariate identified 1338 differentially expressed genes. Cellular growth and proliferation, cell death, cellular function, and maintenance were the main biological processes represented in SAT from subjects who regained weight. Mitochondrial oxidative phosphorylation was the major pattern associated with continued weight loss. CONCLUSIONS: The ability to control body weight loss independent of energy intake or diet composition is reflected in the SAT transcriptome. Although cell proliferation may be detrimental, a greater mitochondrial energy gene expression is suggested as being beneficial for weight control

Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD 104237

Astronomy and Astrophysics, 464, pp. 55-58, http://dx.doi.org./10.1051/0004-6361:20065719International audienc

Energetic particle influence on the Earth's atmosphere

This manuscript gives an up-to-date and comprehensive overview of the effects of energetic particle precipitation (EPP) onto the whole atmosphere, from the lower thermosphere/mesosphere through the stratosphere and troposphere, to the surface. The paper summarizes the different sources and energies of particles, principally galactic cosmic rays (GCRs), solar energetic particles (SEPs) and energetic electron precipitation (EEP). All the proposed mechanisms by which EPP can affect the atmosphere are discussed, including chemical changes in the upper atmosphere and lower thermosphere, chemistry-dynamics feedbacks, the global electric circuit and cloud formation. The role of energetic particles in Earth’s atmosphere is a multi-disciplinary problem that requires expertise from a range of scientific backgrounds. To assist with this synergy, summary tables are provided, which are intended to evaluate the level of current knowledge of the effects of energetic particles on processes in the entire atmosphere