CleAir monitoring system for particulate matter. A case in the Napoleonic Museum in Rome

Monitoring the air particulate concentration both outdoors and indoors is becoming a more relevant issue in the past few decades. An innovative, fully automatic, monitoring system called CleAir is presented. Such a system wants to go beyond the traditional technique (gravimetric analysis), allowing for a double monitoring approach: the traditional gravimetric analysis as well as the optical spectroscopic analysis of the scattering on the same filters in steady-state conditions. The experimental data are interpreted in terms of light percolation through highly scattering matter by means of the stretched exponential evolution. CleAir has been applied to investigate the daily distribution of particulate matter within the Napoleonic Museum in Rome as a test case

Personal UV exposure on a ski-field at an alpine site

International audienceMountain sites experience enhanced ambient UV radiation levels due to the concurrent effects of shorter radiation path-length, low aerosol load and high reflectivity of the snow surfaces. This study was encouraged by the possibility to collect data of personal UV exposure in the mountainous areas of Italy, for the first time. Personal UV exposure (expressed in terms of Exposure Ratio, ER) of two groups of volunteers (ski instructors and skiers) at the Alpine site of La Thuile (Valle d'Aosta region, Italy) was assessed using polysulphone dosimetry which was tested in a mountainous snow-covered environment. In addition measurements of biological markers of individual response to UV exposure such as skin colorimetric parameters were carried out. It was found that snow and altitude of study site affect calibration curves of polysulphone dosimeters in comparison to a situation without snow. The median ER, taking into account the whole sample, is 0.60 in winter, with a range of 0.29 to 1.46, and 1.02 in spring, ranging from 0.46 to 1.72. There are no differences in exposures across skiers and instructors in spring while in winter skiers experience lower values. UV exposures are not sensitive to the use of sunscreen across instructor/skier group by day or by seasons or by photo-type. With regard to colorimetric parameters, the main result was that both skiers and instructors had on average significantly lower values of L* and b* after exposure i.e. becoming darker but the inappropriate sunscreen use did not reveal any changes in skin colorimetric parameters except in one spring day. In conclusions UV intensities on the ski-fields are often significantly higher than those on horizontal surfaces. Given the high levels of exposure observed in the present study, dedicated public heath messages on the correct sunscreen use should be adopted

High-sensitivity C-reactive protein is a predictive factor of adiposity in children : results of the Identification and prevention of Dietary- and lifestyle-induced health Effects in Children and InfantS (IDEFICS) study

Background-Whereas cross-sectional studies have shown that obesity is associated with increased C-reactive protein (CRP) levels in children, little is known about the impact of low-grade inflammation on body mass changes during growth. Methods and Results-We assessed cross-sectionally and longitudinally the association of high-sensitivity (hs)-CRP levels with overweight/obesity and related cardiometabolic risk factors in the Identification and prevention of Dietary-and lifestyle-induced health Effects in Children and InfantS (IDEFICS) cohort. 16 224 children from 8 European countries (2 to 9 years) were recruited during the baseline survey (T0). After the exclusion of 7187 children because of missing hs-CRP measurements and 2421 because of drug use during the previous week, the analysis was performed on 6616 children (Boys=3347; Girls=3269; age=6.3 +/- 1.7 years). Of them, 4110 were reexamined 2 years later (T1). Anthropometric variables, blood pressure, hs-CRP, blood lipids, glucose and insulin were measured. The population at T0 was divided into 3 categories, according to the baseline hs-CRP levels. Higher hs-CRP levels were associated with significantly higher prevalence of overweight/obesity, body mass index (BMI) z-score and central adiposity indices (P values all <0.0001), and with higher blood pressure and lower HDL-cholesterol levels. Over the 2-year follow-up, higher baseline hs-CRP levels were associated with a significant increase in BMI z-score (P<0.001) and significantly higher risk of incident overweight/obesity. Conclusions-Higher hs-CRP levels are associated to higher body mass and overweight/obesity risk in a large population of European children. Children with higher baseline levels of hs-CRP had a greater increase in BMI z-score and central adiposity over time and were at higher risk of developing overweight/obesity during growth

Metastable Vacua in Superconformal SQCD-like Theories

We study dynamical supersymmetry breaking in vector-like superconformal N=1 gauge theories. We find appropriate deformations of the superpotential to overcome the problem of the instability of the non supersymmetric vacuum. The request for long lifetime translates into constraints on the physical couplings which in this regime can be controlled through efficient RG analysis.Comment: 17 pages, 7 figures, JHEP3.cl

Randomised clinical trial: a Lactobacillus GG and micronutrient-containing mixture is effective in reducing nosocomial infections in children, vs. placebo

BACKGROUND: Nosocomial infections are a major public health issue and preventative strategies using probiotics and micronutrients are being evaluated. AIM: To investigate the efficacy of a mixture of Lactobacillus GG and micronutrients in preventing nosocomial infections in children. METHODS: A randomised, double-blind, placebo-controlled trial was conducted in hospitalised children. Children (6 months to 5 years of age) received Lactobacillus GG (6 × 10(9) CFU/day) together with vitamins B and C and zinc or placebo, for 15 days, starting on the first day of hospitalisation. The incidence of gastrointestinal and respiratory nosocomial infections after discharge was determined by follow-up telephone call at 7 days. After 3 months, another telephone call estimated the incidence of further infections during follow-up. RESULTS: Ninety children completed the follow-up. Of 19/90 children with a nosocomial infection (20%), 4/45 children (9%) were in the treatment group and 15/45 (33%) in the placebo group (P = 0.016). Specifically, 2/45 (4%) children in the treatment group vs. 11/45 (24%) children in the placebo group (P = 0.007) presented with diarrhoea. The duration of hospitalisation was significantly shorter in the treatment group (3.9 days ± 1.7 vs. 4.9 ± 1.2; P = 0.003). At the follow-up, a total of 11/45 (24.4%) children in the treatment group had at least one episode of infection compared to 22/45 (48.9%) in the placebo group (P = 0.016). CONCLUSION: A mixture containing Lactobacillus GG and micronutrients may reduce the incidence of nosocomial infections, supporting the hypothesis that this may represent a valid strategy to prevent nosocomial infections

Holographic fermions in charged Gauss-Bonnet black hole

We study the properties of the Green's functions of the fermions in charged Gauss-Bonnet black hole. What we want to do is to investigate how the presence of Gauss-Bonnet coupling constant $\alpha$ affects the dispersion relation, which is a characteristic of Fermi or non-Fermi liquid, as well as what properties such a system has, for instance, the Particle-hole (a)symmetry. One important result of this research is that we find for $q=1$, the behavior of this system is different from that of the Landau Fermi liquid and so the system can be candidates for holographic dual of generalized non-Fermi liquids. More importantly, the behavior of this system increasingly similar to that of the Landau Fermi liquid when $\alpha$ is approaching its lower bound. Also we find that this system possesses the Particle-hole asymmetry when $q\neq 0$, another important characteristic of this system. In addition, we also investigate briefly the cases of the charge dependence.Comment: 22 pages, 6 figures; version published in JHE

Infrared stability of ABJ-like theories

We consider marginal deformations of the superconformal ABJM/ABJ models which preserve N=2 supersymmetry. We determine perturbatively the spectrum of fixed points and study their infrared stability. We find a closed line of fixed points which is IR stable. The fixed point corresponding to the ABJM/ABJ models is stable under marginal deformations which respect the original SU(2)xSU(2) invariance, while deformations which break this group destabilize the theory which then flows to a less symmetric fixed point. We discuss the addition of flavor degrees of freedom. We prove that in general a flavor marginal superpotential does not destabilize the system in the IR. An exception is represented by a marginal coupling which mixes matter charged under different gauge sectors. Finally, we consider the case of relevant deformations which should drive the system to a strongly coupled IR fixed point recently investigated in arXiv:0909.2036 [hep-th].Comment: 1+11 pages, 4 figures; v2: minor correction

Z-extremization and F-theorem in Chern-Simons matter theories

The three dimensional exact R symmetry of N=2 SCFTs extremizes the partition function localized on a three sphere. Here we verify this statement at weak coupling. We give a detailed analysis for two classes of models. The first one is an SU(N)_k gauge theory at large k with both fundamental and adjoint matter fields, while the second is a flavored version of the ABJ theory, where the CS levels are large but they do not necessarily sum up to zero. We study in both cases superpotential deformations and compute the R charges at different fixed points. When these fixed points are connected by an RG flow we explicitly verify that the free energy decreases at the endpoints of the flow between the fixed points, corroborating the conjecture of an F-theorem in three dimensions.Comment: 28 pages, 3 figures, JHEP.cls, minor corrections, references adde

Surprising Connections Between General Relativity and Condensed Matter

This brief review is intended to introduce gravitational physicists to recent developments in which general relativity is being used to describe certain aspects of condensed matter systems, e.g., superconductivity.Comment: 14 pages; based on talk given at GR1