A CF3I-based SDD Prototype for Spin-independent Dark Matter Searches

The application of Superheated Droplet Detectors (SDDs) to dark matter searches has so far been confined to the light nuclei refrigerants C2ClF5 and C4F10 (SIMPLE and PICASSO, respectively), with a principle sensitivity to spin-dependent interactions. Given the competitive results of these devices, as a result of their intrinsic insensitivity to backgrounds, we have developed a prototype trifluoroiodomethane (CF3I)-loaded SDD with increased sensitivity to spin-independent interactions as well. A low (0.102 kgd) exposure test operation of two high concentration, 1 liter devices is described, and the results compared with leading experiments in both spin-dependent and -independent sectors. Although competitive in both sectors when the difference in exposures is accounted for, a problem with fracturing of the detector gel must be addressed before significantly larger exposures can be envisioned.Comment: revised and updated; accepted Astrop. Phy

Temporal trend of the first prescription of nevirapine: the ANRS CO3 Aquitaine Cohort, 1997-2008

International audiencen.

WIMP searches with superheated droplet detectors: Status and Prospects

SIMPLE (Superheated Instrument for Massive ParticLE searches) employs superheated droplet detectors (SDDs) to search for Weakly Interacting Massive Particle (WIMP) dark matter. As a result of the intrinsic SDD insensitivity to minimum ionizing particles and high fluorine content of target liquids, competitive WIMP limits were already obtained at the early prototype stage. We comment here on the expected immediate increase in sensitivity of the program and on future plans to exploit this promising technnique.Comment: 6 pages LaTeX, incl. 2 figures. Presented at the 3rd Intl. Workshop for the Identification of Dark Matter (IDM2000), York, Sept. 200

First Results of the Phase II SIMPLE Dark Matter Search

We report results of a 14.1 kgd measurement with 15 superheated droplet detectors of total active mass 0.208 kg, comprising the first stage of a 30 kgd Phase II experiment. In combination with the results of the neutron-spin sensitive XENON10 experiment, these results yield a limit of |a_p| < 0.32 for M_W = 50 GeV/c2 on the spin-dependent sector of weakly interacting massive particle-nucleus interactions with a 50% reduction in the previously allowed region of the phase space formerly defined by XENON, KIMS and PICASSO. In the spin-independent sector, a limit of 2.3x10-5 pb at M_W = 45 GeV/c2 is obtained.Comment: 4 pages, 4 figures; PRL-accepted version with corrected SI contour (Fig. 4

Neutron-gamma discrimination by pulse analysis with superheated drop detector

Superheated drop detector (SDD) consisting of drops of superheated liquid of halocarbon is irradiated to neutrons and gamma-rays from 252Cf fission neutron source and 137Cs gamma source separately. The analysis of pulse height of the signals in the neutron and gamma-ray sensitive temperature provides strong information on the identification of neutron and gamma-ray induced events.Comment: 19 pages with 8 figures, Accepted in Nucl. Instrum. Meth.

Polymer/carbon nanotube nanocomposites: influence of carbon nanotbues on EVA photodegradation

peer reviewedThe influence of carbon nanotubes on the photodegradation of EVA/carbon nanotube nanocomposites was studied by irradiation under photooxidative conditions (at ? > 300 nm, at 60 °C and in the presence of oxygen). The influence of the nanotubes on both the photooxidation mechanism of EVA and the rates of oxidation of the matrix was characterized on the basis of infrared analysis. On one hand, it was shown that the carbon nanotubes act as inner filters and antioxidants, which contribute to reduction in the rate of photooxidation of the polymeric matrix. On the other hand, it was shown that light absorption could provoke an increase in the local temperature and then induce the photooxidation of the polymer. The competition between these three effects determines the global rate of photooxidation of the polymeric matrix. Several factors are involved, the concentration of the carbon nanotubes, the morphology of the nanotubes and the functionalization of the nanotube surface

Renal Impairment and Cardiovascular Disease in HIV-positive Individuals; The D:A:D Study

BACKGROUND: While the association between renal impairment and cardiovascular disease (CVD) is well established in the general population, the association remains poorly understood in HIV-positive individuals. METHODS: Individuals with >2 estimated glomerular filtration rate (eGFRs) after 1/2/2004 were followed until CVD, death, last visit plus six months or 1/2/2015. CVD was defined as centrally validated myocardial infarction, stroke, invasive cardiovascular procedures or sudden cardiac death. RESULTS: During 8.0 years median follow-up (Interquartile range 5.4-8.9) 1,357 of 35,357 developed CVD (incidence 5.2/1000 person-years [95%confidence interval, CI [5.0-5.5]). Confirmed baseline eGFR and CVD were closely related with 1.8% [95%CI 1.6-2.0%] estimated to develop CVD at five years at eGFR>90 ml/min/1.73m(2), increasing to 21.1% [95%CI 6.6-35.6%] at eGFR<30 ml/min/1.73m(2) The strong univariate relationship between low current eGFR and CVD was primarily explained by increasing age in adjusted analyses, although all eGFRs<80 ml/min/1.73m(2) remained associated with 30-40% increased CVD rates and particular high rates at eGFR<30 ml/min/1.73m(2) (3.08 [95%CI 2.04-4.65]). CONCLUSIONS: Among HIV-positive individuals in a large contemporary cohort a strong relation between confirmed impaired eGFR and CVD was observed. This finding highlights the need for renal preventive measures and intensified monitoring for emerging CVD, in particular in older individuals with continuously low eGFR