Search results for " ROC"

ZERODUR based optical systems for quantum gas experiments in space

2019

Abstract Numerous quantum technologies make use of a microgravity environment e.g. in space. Operating in this extreme environment makes high demands on the experiment and especially the laser system regarding miniaturization and power consumption as well as mechanical and thermal stability. In our systems, optical modules consisting of ZERODUR® based optical benches with free-space optics are combined with fiber components. Suitability of the technology has been demonstrated in the successful sounding rocket missions FOKUS, KALEXUS and MAIUS-1. Here, we report on our toolkit for stable optical benches including mounts, fixed and adjustable mirrors as well as polarization maintaining fiber …

Automatic subgenre classification of heavy metal music

2011

Automatic genre classification of music has been of interest for researchers over a decade. Many success-ful methods and machine learning algorithms have been developed achieving reasonably good results. This thesis explores automatic sub-genre classification problem of one of the most popular meta-genres, heavy metal. To the best of my knowledge this is the first attempt to study the issue. Besides attempting automatic classification, the thesis investigates sub-genre taxonomy of heavy metal music, highlighting the historical origins and the most prominent musical features of its sub-genres. For classification, an algorithm proposed in (Barbedo & Lopes, 2007) was modified and implemented i…

“Proposta di recupero e fruizione delle miniere di roccia asfaltica di Ragusa (Sicilia sud-orientale)-

2008

Novel M. tuberculosis specific IL-2 ELISpot assay discriminates adult patients with active or latent tuberculosis

2018

Background Tuberculosis (TB) still is a major worldwide health problem, with 10.4 million new cases in 2016. Only 5–15% of people infected with M. tuberculosis develop TB disease while others remain latently infected (LTBI) during their lifetime. Thus, the absence of tests able to distinguish between latent infection and active tuberculosis is one of the major limits of currently available diagnostic tools. Methods A total of 215 patients were included in the study as active TB cases (n = 73), LTBI subjects (n = 88) and healthy persons (n = 54). Peripheral blood mononuclear cells (PBMCs) were isolated from each patient and the LIOSpot® TB anti-human IL-2 ELISpot assay was performed to test …

Petrogenetic evolution of metabasalts and metakomatiites of the lower Onverwacht Group, Barberton Greenstone Belt (South Africa)

2019

A well-preserved sequence, by Archean standards, of mantle-derived metabasalts and metakomatiites forms large parts of the lower Onverwacht Group of the Barberton Greenstone Belt (South Africa). To elucidate the origin of mafic and ultramafic rocks from this 3.55 to 3.45 Ga sequence, we present a comprehensive geochemical dataset including major and trace elements as well as Lu-Hf and Sm-Nd isotope compositions for a variety of metavolcanic rocks. These include metabasalts of the amphibolite-facies Sandspruit and Theespruit Formations as well as metabasalts and metakomatiites of the lower greenschist-facies Komati Formation. Based on their incompatible trace element patterns, the basalts of…

Trade me an axe? Interpretive challenges of the distribution and provenance of Neolithic basaltic bifacial tools in Israel

2016

The discovery of a Neolithic quarry and production site for basanite bifacial tools at Giv�at Kipod in Israel has provided new insights into these socially significant artefacts. Geochemical analysis of material from the quarry distinguishes it from other basaltic rock sources in Israel, allowing stone tools from a variety of sites and dated contexts to be assigned a provenance. Results suggest that Giv�at Kipod was an important production centre for over several millennia. It operated primarily on a local, regional level and independently of the parallel manufacture-and-distribution mechanisms of flint bifacials. While flint tools developed in response to the practical requirements of the …

Evidence of deep magma degassing and ascent by geochemistry of peripheral gas emissions at Mount Etna (Italy): Assessment of the magmatic reservoir p…

2003

[1] Five gas discharges in the area of Mount Etna volcano (Italy) and in the near Hyblean plateau have been monitored since 1996. All the emissions displayed low contributions from crustal fluids, whereas magmatic gases were the main component. Selective dissolution of these gases into hydrothermal aquifers has been recognized and modeled, allowing us to calculate the original composition of the magma-released gases. The inferred composition of the magmatic gases exhibits synchronous variations of He/Ne and He/CO2 ratios, which are coherent with the magma degassing process. On the basis of numerical simulations of volatile degassing from Etnean basalts we have computed the initial and final…

A mechanism forming silicic segregations from basaltic magma discovered in igneous rocks of Western Sicily

1983

Summary. Mechanisms forming silicic segregations from basaltic magmas are considered of primary importance when dealing with magmatic problems. However, the processes which give rise to silicic segregations from basaltic magmas are so far obscure. Fortunately, the discovery of spheroidal felsic masses in some basic rocks of Western Sicily throws light on this subject. To clarify the relationships between felsic and basic fractions particular attention has been paid to the interactions which occurred at their contact. Textural evidence indicates that the accretion mechanism of the Sicilian felsic segregations tends to obliterate the silicate liquid immiscibility effects and suggests that the…

The radiogenic isotope composition of the high-latitude North Atlantic mantle

1997

New Sr, Nd, and Pb isotope data on North Atlantic high-latitude (about 69°30'N to 76°30'N) intraplate and ridge volcanic rocks, together with published data, are used to evaluate the mantle sources contributing to Iceland and the surrounding ridges. Considerable overlap between Icelandic lavas and depth-filtered North Atlantic mid-oceanic-ridge basalts (MORBs) in all isotope plots confirm that a MORB asthenosphere-plume mixing model can explain the ranges of isotope compositions found on Iceland. Regional isotope patterns north of lat 53°N show two distinct mantle domains. Lavas forming a low-radiogenic-Pb, high-radiogenic-Sr array occur north of central Iceland, whereas volcanic rocks form…

Geochemistry, petrogenesis and tectonic setting of the Samothraki mafic suite, NE Greece: Trace-element, isotopic and zircon age constraints

2009

Abstract The Samothraki mafic suite in the north-eastern Aegean Sea, Greece, is an ‘in situ’ magmatic complex comprising gabbros, sparse dykes and basalt flows and pillows cut by late dolerite dykes. We have determined the age of the complex by SHRIMP zircon geochronology of a gabbro as 159.9 ± 4.5 Ma (i.e. Oxfordian; early Late Jurassic), which precludes any correlation with the so-called Lesvos ophiolite further south (253.1 ± 5.6 Ma; Latest Permian). Six distinct, hitherto unrecognised, geochemical groups have been identified among the basalts and dolerites of the Samothraki mafic suite on the basis of trace-element and Nd–Sr isotopic characteristics. All groups show the presence of an e…