Cluster physics from joint weak gravitational lensing and Sunyaev-Zel'dovich data

We present a self consistent method to perfom a joint analysis of Sunyaev-Zel'dovich and weak gravitational lensing observation of galaxy clusters. The spatial distribution of the cluster main constituents is described by a perturbative approach. Assuming the hydrostatic equilibrium and the equation of state, we are able to deduce, from observations, maps of projected gas density and gas temperature. The method then naturally entails a X-ray emissivity prediction which can be compared to observed X-ray emissivity maps. When tested on simulated clusters (noise free), this prediction turns out to be in very good agreement with the simulated surface brightness. The simulated and predicted surface brightness images have a correlation coefficient higher than 0.9 and the total flux differ by 0.9 % or 9 % in the two simulated clusters we studied. The method should be easily used on real data in order to provide a physical description of the cluster physics and of its constituents. The tests performed show that we can recover the amount and the spatial distributions of both the baryonic and non-baryonic material with an accuracy better than 10 %. So, in principle, in it might indeed help to alleviate some well known bias affecting, eg baryon fraction measurements

IL-6 gene amplification and expression in human glioblastomas

The aggressiveness of human gliomas appears to be correlated with the upregulation of interleukin 6 (IL-6) gene. Using quantitative PCR methods, we detected amplification and expression of the IL-6 gene in 5 of 5 primary glioblastoma samples and in 4 of 5 glioblastoma cell lines. This finding suggests that the amplification of IL-6 gene may be a common feature in glioblastomas and may contribute to the IL-6 over-expression. © 2001 Cancer Research Campaign http://www.bjcancer.co

The Firmicutes/Bacteroidetes ratio of the human microbiota changes with age

<p>Abstract</p> <p>Background</p> <p>In humans, the intestinal microbiota plays an important role in the maintenance of host health by providing energy, nutrients, and immunological protection. Applying current molecular methods is necessary to surmount the limitations of classical culturing techniques in order to obtain an accurate description of the microbiota composition.</p> <p>Results</p> <p>Here we report on the comparative assessment of human fecal microbiota from three age-groups: infants, adults and the elderly. We demonstrate that the human intestinal microbiota undergoes maturation from birth to adulthood and is further altered with ageing. The counts of major bacterial groups <it>Clostridium leptum, Clostridium coccoides</it>, <it>Bacteroidetes, Bifidobacterium, Lactobacillus </it>and <it>Escherichia coli </it>were assessed by quantitative PCR (qPCR). By comparing species diversity profiles, we observed age-related changes in the human fecal microbiota. The microbiota of infants was generally characterized by low levels of total bacteria. <it>C. leptum </it>and <it>C. coccoides </it>species were highly represented in the microbiota of infants, while elderly subjects exhibited high levels of <it>E. coli </it>and <it>Bacteroidetes</it>. We observed that the ratio of <it>Firmicutes </it>to <it>Bacteroidetes </it>evolves during different life stages. For infants, adults and elderly individuals we measured ratios of 0.4, 10.9 and 0.6, respectively.</p> <p>Conclusion</p> <p>In this work we have confirmed that qPCR is a powerful technique in studying the diverse and complex fecal microbiota. Our work demonstrates that the fecal microbiota composition evolves throughout life, from early childhood to old age.</p

The radial acceleration relation is a natural consequence of the baryonic Tully-Fisher relation

Galaxies covering several orders of magnitude in stellar mass and a variety of Hubble types have been shown to follow the radial acceleration relation (RAR), a relationship between g_(obs), the observed circular acceleration of the galaxy, and g_(bar), the acceleration due to the total baryonic mass of the galaxy. For accelerations above 10^(10) m s^(-2), g_(obs), traces g_(bar), asymptoting to the 1:1 line. Below this scale, there is a break in the relation such that g_(obs) ~ g_(bar)^(1/2). We show that the RAR slope, scatter, and the acceleration scale are all natural consequences of the well-known baryonic Tully–Fisher relation (BTFR). We further demonstrate that galaxies with a variety of baryonic and dark matter (DM) profiles and a wide range of dark halo and galaxy properties (well beyond those expected in Cold Dark Matter (CDM) theory) lie on the RAR if we simply require that their rotation curves satisfy the BTFR. We explore conditions needed to break this degeneracy: subkiloparsec resolved rotation curves inside of cored DM-dominated profiles and/or outside ≫ 100 kpc could lie on BTFR but deviate in the RAR, providing new constraints on DM

REDRISK: reduction of the virus risk in shellfish harvesting areas

Filter feeding bivalve shellfish can accumulate human pathogenic bacteria and viruses if grown in sewage-contaminated waters. Current consumer protection legislation relies on classification of harvesting areas based on their sanitary quality, using E coli as an indicator of sewage contamination. Advances in viral monitoring have shown that E coli can underestimate the extent of the contamination. The most common cause of gastroenteritis associated with shellfish is norovirus, commonly known as winter vomiting virus. The REDRISK project was undertaken to investigate the main environmental factors that cause viral contamination in shellfish. The REDRISK project is part of a EU research pillar with parallel research being undertaken in the UK, France and Spain. A recently developed technique to quantify norovirus in shellfish, real-time PCR, has been used in the REDRISK project. Clew Bay, in Co. Mayo was chosen as the study area in Ireland. The bay is generally considered to have good water quality but with certain areas subject to intermittent sewage contamination. The cooperation of local producers and organisations such as the Clew Bay Marine Forum and the Native Oyster Co-op greatly helped the project. The project was divided into a two-phased approach. Phase one involved the identification of contamination sources impacting the bay through a sanitary survey and selection of appropriate sites for further study. Results of the first phase of this study were presented previously at this forum (Keaveney, et al 2006) and the characteristics of the sites selected for study and locations within the bay are shown in table 1 and figure 1 respectively. The second phase of the project focused on monitoring environmental conditions and microbiological levels in shellfish to identify environmental conditions leading to viral contamination. This paper reports the finding of this monitoring

Preliminary results from a survey of oyster production areas in Ireland for norovirus

A survey of 18 oyster production areas in Ireland for norovirus (NoV) contamination was initiated in August 2006. The findings presented are the preliminary results from the first seven months of the survey. Prior to the survey commencing, a simple desk bask sanitary survey of each area was undertaken. This provided an assessment enabling each site to be ranked into 3 categories (low, medium and high) on the basis of the risk of NoV contamination. Samples were collected on a monthly basis and tested for the presence of NoV using semi-quantitative real-time PCR allowing relative quantitation of NoV levels. A correlation was observed between occurrence and levels of NoV detected and the risk categories ascribed to each production area. To date NoV was detected in 60.7, 30.0 and 2.5 percent of samples from the high, medium and low risk categorised areas, respectively. A strong seasonal bias towards increased winter contamination was observed with NoV detected in 15.5 and 50 % of samples in August and February, respectively. The preliminary results from this survey indicate that it may be possible to predict the relative risk of NoV contamination in a shellfish harvesting area. This in conjunction with targeted NoV monitoring using real-time PCR could aid the further development of risk management procedures in shellfisheries

Sunscreen use and intentional exposure to ultraviolet A and B radiation: a double blind randomized trial using personal dosimeters

A previous randomized trial found that sunscreen use could extend intentional sun exposure, thereby possibly increasing the risk of cutaneous melanoma. In a similarly designed trial, we examined the effect of the use of sunscreens having different sun protection factor (SPF) on actual exposure to ultraviolet B (UVB) and ultraviolet A (UVA) radiation. In June 1998, 58 European participants 18–24 years old were randomized to receive a SPF 10 or 30 sunscreens and were asked to complete daily records of their sun exposure during their summer holidays of whom 44 utilized a personal UVA and UVB dosimeter in a standard way during their sunbathing sessions. The median daily sunbathing duration was 2.4 hours in the SPF 10 group and 3.0 hours in the SPF 30 group (P = 0.054). The increase in daily sunbathing duration was paralleled by an increase in daily UVB exposure, but not by changes in UVA or UVB accumulated over all sunbathing sessions, or in daily UVA exposure. Of all participants, those who used the SPF 30 sunscreen and had no sunburn spent the highest number of hours in sunbathing activities. Differences between the two SPF groups in total number of sunbathing hours, daily sunbathing duration, and daily UVB exposure were largest among participants without sunburn during holidays. Among those with sunburn, the differences between the two groups tended to reduce. In conclusion, sunscreens used during sunbathing tended to increase the duration of exposures to doses of ultraviolet radiation below the sunburn threshold. © 2000 Cancer Research Campaig

Detection of human viruses in shellfish and update on REDRISK research project, Clew Bay, Co. Mayo

This paper describe the progress in norovirus detection methods and initial results from the REDRISK study