Tubular structures of GaS

In this Brief Report we demonstrate, using density-functional tight-binding theory, that gallium sulfide (GaS) tubular nanostructures are stable and energetically viable. The GaS-based nanotubes have a semiconducting direct gap which grows towards the value of two-dimensional hexagonal GaS sheet and is in contrast to carbon nanotubes largely independent of chirality. We further report on the mechanical properties of the GaS-based nanotubes

Biomarkers of Multiple Sclerosis

The search for an ideal multiple sclerosis biomarker with good diagnostic value, prognostic reference and an impact on clinical outcome has yet to be realized and is still ongoing. The aim of this review is to establish an overview of the frequent biomarkers for multiple sclerosis that exist to date. The review summarizes the results obtained from electronic databases, as well as thorough manual searches. In this review the sources and methods of biomarkers extraction are described; in addition to the description of each biomarker, determination of the prognostic, diagnostic, disease monitoring and treatment response values besides clinical impact they might possess. We divided the biomarkers into three categories according to the achievement method: laboratory markers, genetic-immunogenetic markers and imaging markers. We have found two biomarkers at the time being considered the gold standard for MS diagnostics. Unfortunately, there does not exist a single solitary marker being able to present reliable diagnostic value, prognostic value, high sensitivity and specificity as well as clinical impact. We need more studies to find the best biomarker for MS.publishersversionPeer reviewe

The ROSAT Wide Field Camera all-sky survey of extreme-ultraviolet sources. I - The Bright Source Catalogue

The first all-sky survey for cosmic sources of extreme-ultraviolet radiation has been carried out with the UK Wide Field Camera on ROSAT. A first reduction of the survey data has yielded a catalogue of 383 relatively bright EUV sources, forming the WFC Bright Source Catalogue. This represents a 30-fold increase in the number of astrophysical objects detected in the ~ 60–200 eV energy band and covers a flux range, in each of the two survey bands, of more than 2000. A search of the (typically ~ 1-arcmin) error circles of the WFC sources, using a variety of catalogues and the SIMBAD data base, has identified probable optical counterparts of ~ 73 per cent, including many active stars, white dwarf stars and a variety of other galactic and extragalactic objects. A follow-up programme of optical spectroscopy has since added further identifications, but some 13 per cent of the EUV sources remain unidentified