Conceptual development of a ground-based radio-beacon navigation system for use on the surface of the moon

A spread-spectrum radio-beacon navigation system for use on the lunar surface is described. The subjects discussed are principle of operation and specifications to include power requirements, operating frequencies, weight, size, and range

Magnetic anisotropy in van-der-Waals ferromagnet VI3

A comprehensive study of magnetocrystalline anisotropy of a layered van-der-Waals ferromagnet VI3 was performed. We measured angular dependences of the torque and magnetization with respect to the direction of the applied magnetic field within the "ac" plane perpendicular to and within the basal ab plane, respectively. A two-fold butterfly-like signal was detected by magnetization in the perpendicular "ac" plane. This signal symmetry remains conserved throughout all magnetic regimes as well as through the known structural transition down to the lowest temperatures. The maximum of the magnetization signal and the resulting magnetization easy axis is significantly tilted from the principal c axis by ~40{\deg}. The close relation of the magnetocrystalline anisotropy to the crystal structure was documented. In contrast, a two-fold-like angular signal was detected in the paramagnetic region within the ab plane in the monoclinic phase, which transforms into a six-fold-like signal below the Curie temperature TC. With further cooling, another six-fold-like signal with an angular shift of ~30{\deg} grows approaching TFM. Below TFM, in the triclinic phase, the original six-fold-like signal vanishes, being replaced by a secondary six-fold-like signal with an angular shift of ~30{\deg}.Comment: 14 pages, 10 figure

Resolution Studies on Silicon Strip Sensors with fine Pitch

In June 2008 single-sided silicon strip sensors with 50 $\mu$m readout pitch were tested in a highly energetic pion beam at the SPS at CERN. The purpose of the test was to evaluate characteristic detector properties by varying the strip width and the number of intermediate strips. The experimental setup and first results for the spatial resolution are discussed.Comment: proceeding of the International Linear Collider Workshop 2008 (LCWS08); corrected typos, added reference for section

P07-05. HIV and STI prevalence among men who have sex with men (MSM) recruited through respondent driven sampling (RDS) in Buenos Aires, Argentina

Fil: Pando, María A. Centro Nacional de Referencia para el SIDA; Argentina.Fil: Marone, Rubén. Nexo Asociación Civil; Argentina.Fil: Balán, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Dolezal, Curtis. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Squiquera, Luis. Nexo Asociación Civil; Argentina. Fil: Balan, Iván C. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Picconi, María Alejandra. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Gonzales, J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Virus Oncogénicos; Argentina.Fil: Rey, Jorge. Hospital de Clínicas José de San Martín; Argentina.Fil: Fernandez Toscano, M. Hospital de Clínicas José de San Martín; Argentina.Fil: Rodriguez Fermepín, Marcelo. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Gallo Vaulet, Lucia. UBA. Laboratorio de Inmunología Clínica; Argentina.Fil: Carballo Dieguez, Alex. Columbia University. HIV Center for Clinical and Behavioral Studies; Estados Unidos.Fil: Avila, María M. Centro Nacional de Referencia para el SIDA; Argentina.Background MSM constitute one of the populations most affected by HIV and other STIs in Argentina. Previous prevalence studies were based on convenience samples. RDS, a methodology designed to access hidden populations, is being used for the first time in Argentina to recruit MSM. Methods RDS recruitment started in November 2007 with 16 first generation participants (seeds) who were selected for their potential to tap in MSM networks. Recruitment is ongoing. Men must be 18 years of age or older, be residents of Buenos Aires, self-report having sex with men at least 10 times in their lives and at least once in the past six months. They must have a coupon indicating they have been referred by a study participant. Specimens are being collected for HIV and STI diagnosis. All data are weighted using the RDS Analysis Tool (RDSAT). Results To date, 333 MSM were recruited through RDS showing a prevalence of 11.3, 16.6, 7.9, 17.6, 4.0 and 88.3% for HIV, HBV, HCV, T. pallidum, Chlamydia and HPV, respectively. Chlamydia and HPV diagnoses were only performed in 73 and 79 participants, respectively. Among HPV positive individuals, 47.8% had almost one of these high risk types (16, 58, 33, 45, 18 and 31) and 32% had multiple infections with 2 or more types. Conclusion Compared with previous studies, these results show similar HIV, HBV and T. pallidum prevalences but higher HCV prevalence. For the first time, an elevated prevalence of HPV was detected on MSM, with high frequency of types associated with ano-genital cancer. Preliminary analyses of socio demographic data show that RDS helps recruit a diversity of MSM, particularly of lower socio-economic level usually missed with other recruitment methods. The high prevalence of coinfections in this population should be taken into account if MSM are part of vaccine trials given that STI may increase HIV sexual transmission

ATLAS silicon module assembly and qualification tests at IFIC Valencia

ATLAS experiment, designed to probe the interactions of particles emerging out of proton proton collisions at energies of up to 14 TeV, will assume operation at the Large Hadron Collider (LHC) at CERN in 2007. This paper discusses the assembly and the quality control tests of forward detector modules for the ATLAS silicon microstrip detector assembled at the Instituto de Fisica Corpuscular (IFIC) in Valencia. The construction and testing procedures are outlined and the laboratory equipment is briefly described. Emphasis is given on the module quality achieved in terms of mechanical and electrical stability.Comment: 23 pages, 38 EPS figures, uses JINST LaTeX clas

Experimental Tests of Neutron Shielding for the ATLAS Forward Region

Experimental tests devoted to the optimization of the neutron shielding for the ATLAS forward region were performed at the CERN-PS with a 4 GeV/c proton beam. Spectra of fast neutrons, slow neutrons and gamma rays escaping a block of iron (40$\times$40$\times$80 cm$^3$) shielded with different types of neutron and gamma shields (pure polyethylene - PE, borated polyethylene - BPE, lithium filled polyethylene - LiPE, lead, iron) were measured by means of plastic scintillators, a Bonner spectrometer, a HPGe detector and a slow neutron detector. Effectiveness of different types of shielding agaisnt neutrons and $\gamma$-rays were compared. The idea of a segmented outer layer shielding (iron, BPE, iron, LiPE) for the ATLAS Forward Region was also tested

The ATLAS SCT grounding and shielding concept and implementation

This paper presents a complete description of Virgo, the French-Italian gravitational wave detector. The detector, built at Cascina, near Pisa (Italy), is a very large Michelson interferometer, with 3 km-long arms. In this paper, following a presentation of the physics requirements, leading to the specifications for the construction of the detector, a detailed description of all its different elements is given. These include civil engineering infrastructures, a huge ultra-high vacuum (UHV) chamber (about 6000 cubic metres), all of the optical components, including high quality mirrors and their seismic isolating suspensions, all of the electronics required to control the interferometer and for signal detection. The expected performances of these different elements are given, leading to an overall sensitivity curve as a function of the incoming gravitational wave frequency. This description represents the detector as built and used in the first data-taking runs. Improvements in different parts have been and continue to be performed, leading to better sensitivities. These will be detailed in a forthcoming paper