Investigations of fast neutron production by 190 GeV/c muon interactions on different targets

The production of fast neutrons (1 MeV - 1 GeV) in high energy muon-nucleus interactions is poorly understood, yet it is fundamental to the understanding of the background in many underground experiments. The aim of the present experiment (CERN NA55) was to measure spallation neutrons produced by 190 GeV/c muons scattering on carbon, copper and lead targets. We have investigated the energy spectrum and angular distribution of spallation neutrons, and we report the result of our measurement of the neutron production differential cross section.Comment: 19 pages, 11 figures ep

Emotional modulation of body-selective visual areas

Emotionally expressive faces have been shown to modulate activation in visual cortex, including face-selective regions in ventral temporal lobe. Here we tested whether emotionally expressive bodies similarly modulate activation in body-selective regions. We show that dynamic displays of bodies with various emotional expressions, versus neutral bodies, produce significant activation in two distinct body-selective visual areas, the extrastriate body area (EBA) and the fusiform body area (FBA). Multi-voxel pattern analysis showed that the strength of this emotional modulation was related, on a voxel-by-voxel basis, to the degree of body selectivity, while there was no relation with the degree of selectivity for faces. Across subjects, amygdala responses to emotional bodies positively correlated with the modulation of body-selective areas. Together, these results suggest that emotional cues from body movements produce topographically selective influences on category-specific populations of neurons in visual cortex, and these increases may implicate discrete modulatory projections from the amygdala

Determination of Strong-Interaction Widths and Shifts of Pionic X-Rays with a Crystal Spectrometer

Pionic 3d-2p atomic transitions in F, Na, and Mg have been studied using a bent crystal spectrometer. The pionic atoms were formed in the production target placed in the external proton beam of the Space Radiation Effects Laboratory synchrocyclotron. The observed energies and widths of the transitions are E=41679(3) eV and Γ=21(8) eV, E=62434(18) eV and Γ=22(80) eV, E=74389(9) eV and Γ=67(35) eV, in F, Na, and Mg, respectively. The results are compared with calculations based on a pion-nucleus optical potential

Sub MeV Particles Detection and Identification in the MUNU detector ((1)ISN, IN2P3/CNRS-UJF, Grenoble, France, (2)Institut de Physique, Neuch\^atel, Switzerland, (3) INFN, Padova Italy, (4) Physik-Institut, Z\"{u}rich, Switzerland)

We report on the performance of a 1 m$^{3}$ TPC filled with CF$_{4}$ at 3 bar, immersed in liquid scintillator and viewed by photomultipliers. Particle detection, event identification and localization achieved by measuring both the current signal and the scintillation light are presented. Particular features of $\alpha$ particle detection are also discussed. Finally, the ${54}$Mn photopeak, reconstructed from the Compton scattering and recoil angle is shown.Comment: Latex, 19 pages, 20 figure

Design and validation of a partial-genome microarray for transcriptional profiling of the Bradyrhizobium japonicum symbiotic gene region

The design and use of a pilot microarray for transcriptome analysis of the symbiotic, nitrogen-fixing Bradyrhizobium japonicum is reported here. The custom-synthesized chip (Affymetrix GeneChip®) features 738 genes, more than half of which belong to a 400-kb chromosomal segment strongly associated with symbiosis-related functions. RNA was isolated following an optimized protocol from wild-type cells grown aerobically and microaerobically, and from cells of aerobically grown regR mutant and microaerobically grown nifA mutant. Comparative microarray analyses thus revealed genes that are transcribed in either a RegR- or a NifA-dependent manner plus genes whose expression depends on the cellular oxygen status. Several genes were newly identified as members of the RegR and NifA regulons, beyond genes, which had been known from previous work. A comprehensive transcription analysis was performed with one of the new RegR-controlled genes (id880). Expression levels determined by microarray analysis of selected NifA- and RegR-controlled genes corresponded well with quantitative real-time PCR data, demonstrating the high complementarity of microarray analysis to classical methods of gene expression analysis in B. japonicum. Nevertheless, several previously established members of the NifA regulon were not detected as transcribed genes by microarray analysis, confirming the potential pitfalls of this approach also observed by other authors. By and large, this pilot study has paved the way towards the genome-wide transcriptome analysis of the 9.1-Mb B. japonicum genom

A method for the stochastic modeling of karstic systems accounting for geophysical data: an example of application in the region of Tulum, Yucatan Peninsula (Mexico)

The eastern coast of the Yucatan Peninsula, Mexico, contains one of the most developed karst systems in the world. This natural wonder is undergoing increasing pollution threat due to rapid economic development in the region of Tulum, together with a lack of wastewater treatment facilities. A preliminary numerical model has been developed to assess the vulnerability of the resource. Maps of explored caves have been completed using data from two airborne geophysical campaigns. These electromagnetic measurements allow for the mapping of unexplored karstic conduits. The completion of the network map is achieved through a stochastic pseudo-genetic karst simulator, previously developed but adapted as part of this study to account for the geophysical data. Together with the cave mapping by speleologists, the simulated networks are integrated into the finite-element flow-model mesh as pipe networks where turbulent flow is modeled. The calibration of the karstic network parameters (density, radius of the conduits) is conducted through a comparison with measured piezometric levels. Although the proposed model shows great uncertainty, it reproduces realistically the heterogeneous flow of the aquifer. Simulated velocities in conduits are greater than 1cm s−1, suggesting that the reinjection of Tulum wastewater constitutes a pollution risk for the nearby ecosystem

Hourly resolved cloud modification factors in the ultraviolet

Cloud impacts on the transfer of ultraviolet (UV) radiation through the atmosphere can be assessed by using a cloud modification factor (CMF). CMF, which is based on total global solar irradiation (SOL<sub>CMF</sub>), has proved to be a solid basis to derive CMFs for the UV radiation (UV<sub>CMF</sub>). This is an advantage, because total global irradiance, the basis for SOL<sub>CMF</sub>, is frequently measured and forecasted by numerical weather prediction systems and includes all relevant effects for radiation transmission, such as cloud optical depth, different cloud layers, multiple reflection, as well as the distinct difference as to whether the solar disc is obscured by clouds or not. In the UV range clouds decrease the irradiance to a lesser extent than in the visible and infrared spectral range. Thus the relationship between CMFs for solar radiation and for UV-radiation is not straight forward, but will depend on whether, for example, the solar zenith angle (SZA) and wavelength band or action spectrum in the UV have been taken into consideration. Den Outer et al. provide a UV<sub>CMF</sub> algorithm on a daily basis, which accounts for these influences. It requires as input a daily SOL<sub>CMF</sub> and the SZA at noon. The calculation of SOL<sub>CMF</sub> uses the clear-sky algorithm of the European Solar Radiation Atlas to account for varying turbidity impacts. The algorithm's capability to derive hourly UV<sub>CMFs</sub> based on the SZA at the corresponding hour and its worldwide applicability is validated for erythemal UV using observational data retrieved from the databases of the COST-Action 726 on "Long-term changes and climatology of UV radiation over Europe" and the USDA UV-B Monitoring Program. The clear-sky part of the models has proved to be of good quality. Accumulated to daily doses it forms a tight cluster of points to the highest measured daily sums. All sky model performances for hourly resolution are shown to be comparable in accuracy with the well performing daily models of the COST-726 model intercomparison

The VZV/IE63-specific T cell response prevents herpes zoster in fingolimod-treated patients.

OBJECTIVE: To assess longitudinally the antiviral immune response of T cells from patients with multiple sclerosis (MS) treated with fingolimod (FTY) vs other disease-modifying treatments (DMTs). METHODS: We assessed cellular immune responses specific to influenza virus (FLU), JC virus (JCV), and varicella-zoster virus (VZV) using quantification of interferon-γ secretion by enzyme-linked immunospot in patients with MS on FTY (n = 31), including 2 with herpes zoster (HZ), natalizumab (n = 11), and other DMTs (n = 11). We used viral lysates for FLU and VZV and a pool of peptides for FLU, JCV (VP-1), and VZV (IE63). RESULTS: Besides an expected drop of T cells, we found that, proportionally to the number of CD3(+) T cells, only FTY-treated patients with MS exhibited an increased VZV/IE63-specific T cell response peaking 6 months into treatment, a response that returned to baseline after 12 and 24 months. Two FTY-treated patients developed an HZ 6 months into treatment, coinciding with an absent VZV/IE63-specific T cell response. However, cellular immune responses specific to VZV lysate, JCV, and FLU (lysate and pool of peptide epitopes) were similar between all 3 categories (FTY, natalizumab, and other DMTs) of study patients. CONCLUSIONS: FTY-treated patients with MS exhibit an increased VZV/IE63-specific cellular immune response after 6 months of treatment. FTY-treated patients who develop an HZ are not able to mount such a response, suggesting that a T cell response directed against this viral protein may be key in preventing the occurrence of HZ