[Changes in behaviors and indicators of mental health between 2006 and 2010 in the French working population]. / Évolution des comportements et indicateurs de santé mentale entre 2006 et 2010 dans la population au travail en France.

BACKGROUND: The 2008 economic crisis may have had an impact on mental health but the studies on this topic are sparse, in particular among the working population. However, mental health at work is a crucial issue involving substantial costs and consequences. The aim of the study was to assess changes in behaviors and indicators of mental health in the French working population between 2006 and 2010, and to explore the differential changes according to age, origin, occupation, activity sector, public/private sector, self-employed/employee status and work contract. METHODS: The data came from the prospective national representative Santé et itinéraire professionnel (SIP) survey, including a sample of 5600 French workers interviewed in 2006 and 2010. The behaviors and indicators of mental health studied were excessive alcohol consumption, smoking, sleep problems (sleep disorders and/or insufficient sleep duration), psychotropic drug use (antidepressants, anxiolytics and/or hypnotics), and poor self-reported health. Generalized estimating equations were used to analyze changes in behaviors and indicators of mental health, and the analyses were adjusted for age. Covariates (age, origin, occupation, activity sector, public/private sector, self-employed/employee status and type of contract) were added separately to assess differential changes. RESULTS: Increases in excessive alcohol consumption among women, sleep problems among men, and smoking, insufficient sleep duration and poor self-reported health for both genders were observed in the French working population between 2006 and 2010. Some differential changes were observed, negative changes being more likely to affect young workers and workers with a permanent contract. CONCLUSION: Prevention policies should consider that behavior and indicators of mental health may deteriorate in times of economic crisis, especially among some sub-groups of the working population, such as young workers and workers with a permanent contract. These changes might foreshadow a forthcoming increase in mental disorders.

The use of a Ga+ focused ion beam to modify graphene for device applications.

In this work, we clarify the features of the lateral damage of line defects in single layer graphene. The line defects were produced through well-controlled etching of graphene using a Ga(+) focused ion beam. The lateral damage length was obtained from both the integrated intensity of the disorder induced Raman D band and the minimum ion fluence. Also, the line defects were characterized by polarized Raman spectroscopy. It was found that graphene is resilient under the etching conditions since the intensity of the defect induced Raman D peak exhibits a dependence on the direction of the lines relative to the crystalline lattice and also on the direction of the laser polarization relative to the lines. In addition, electrical measurements of the modified graphene were performed. Different ion fluences were used in order to obtain a completely insulating defect line in graphene, which was determined experimentally by means of charge injection and electric force microscopy measurements. These studies demonstrate that a Ga+ ion column combined with Raman spectroscopy is a powerful technique to produce and understand well-defined periodic arrays of defects in graphene, opening possibilities for better control of nanocarbon devices.

Thermal enhancement of chemical doping in graphene: a Raman spectroscopy study.

The Raman spectrum of monolayer graphene deposited on the top of a silicon oxide/silicon substrate was investigated as a function of temperature up to 515 K. An anomalous temperature dependence of the Raman features was observed, including an important frequency upshift for the Raman G band at room temperature, after the heating process. On the other hand, the frequency of the Raman G(') band is only slightly affected by the thermal treatment. We discuss our experimental results in terms of doping and strain effects associated with the interaction of graphene with the substrate and with the presence of water in the sample. We conclude that the doping effect gives the most important contribution to the spectral changes observed after the thermal cycle.

Observation of distinct electron-phonon couplings in gated bilayer graphene.

A Raman study of a back gated bilayer graphene sample is presented. The changes in the Fermi level induced by charge transfer splits the Raman G band, hardening its higher component and softening the lower one. These two components are associated with the symmetric (S) and antisymmetric vibration (AS) of the atoms in the two layers, the later one becoming Raman active due to inversion symmetry breaking. The phonon hardening and softening are explained by considering the selective coupling of the S and AS phonons with interband and intraband electron-hole pairs.

Immunodiagnosis of ocular toxocariasis using Western-blot for the detection of specific anti-Toxocara IgG and CAP for the measurement of specific anti-Toxocara IgE.

A prospective multicentric study was carried out to assess both the performance of Western-blot (WB) detecting specific anti-Toxocara IgG and that of CAP measuring specific IgE titre for the immunodiagnosis of ocular toxocariasis. For 14 outpatients presenting ophthalmic symptoms (choroiditis, chorioretinitis, papillar oedema, hyalitis, retinal detachment and/or uveitis), samples of serum and aqueous fluid (AF) were sent to the Department of Parasitology, University Hospitals, Toulouse, France. All patients but two tested positive with WB on the serum; 13 WB tests were performed on the AF, 12 of which were positive. The two patients who had a negative WB serum result tested positive for the AF. Specific IgE detection was considered as a complementary test of WB. Two patients showed a greater specific IgE titre in the AF than in the serum, and one had a positive result in the AF, but not in the serum. These six patients were considered as clear cases of ocular toxocariasis. Western-blot coupled with specific anti-Toxocara IgE detection appeared therefore to be an accurate procedure for the immunodiagnosis of ocular toxocariasis, provided the testing was simultaneously performed on the serum and AF.