735 research outputs found

    The system to fill with oil the empty Break Out Boxes (BOBs) of the KM3NeT Detection Units

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    The KM3NeT collaboration aims to construct the largest underwater neutrino telescope in the Mediterranean sea. The detector is located in two sites, one in front of Toulon at 2500m sea depth and one SE Capo Passero in Sicily at 3500m depth. On both sites, one or two blocks of 115 Detection Units (DU) are connected to shore , each Du being composed by a Vertical Electro-Optical Cable (VEOC) connecting 18 Digital Optical Modules (DOMs). In this report we describe the integration of the DU carried out in our INFN laboratory in Genova, in particular one important phase of the process where some components in the VEOC have to be carefully filled with oil before connection to the DOMs

    The "Automated Welding Machine" in the integration process of the Detection Units of the KM3Net experiment: general description

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    This note describes one of the tools used during Process-1 of the integration of the Detection Units (DUs) in the KM3NeT experiment. In particular, the device is designed to seal the Break-out-box (BOB). The BOB is a box interface between a Digital Optical Module (DOM) and the electrooptical cable (VEOC) for power and optical connection of each optical module (DOM) to the DU. The original manual version of the tool developed by NIKHEF was automatized by INFN-LNS in order to guarantee a reproducible operation in the recursive process of the DU integration and two samples have been realized for the integration sites at LNS and Genova respectively

    Comparing activity and space patterns of the European pond turtle, Emys orbicularis (L., 1758) in a Venice Lagoon wetland area: implications for conservation planning and management

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    Behavioural and spatial distribution analyses were quantified during a phase of activity and lethargy in a wild population of the European pond turtle inhabiting a protected internal wetland area of the Venice lagoon. The marked individuals (13 males and 16 females) provided informative radiotracking data to study differential patterns of activity, dispersion and habitat use between the two study periods ("October-November both 2019 and 2020" and "June-July 2020"). The differences in the movements behaviours and habitat selection were affected by period. Movements were higher in the period of activity than lethargy, but they were not influenced by sex and size. The presence of the European pond turtle in the transitional woodland/shrubs and brackish water valley habitats was significantly higher in the period of activity than lethargy. During the latter one, pond turtles were observed to brumate gregariously in a small area for brumation, usually in shallow water. In contrast, all individuals have changed water bodies during the activity period. Part of those movements has occurred towards aquatic habitat with higher salinities 1-17%o (mean: 10.64%o). These findings provide a set of information to better understand the behavioural ecology of Emys orbicularis in the lagoon area. This is of relevance for management actions and for the conservation of this threatened species

    Comparison among Cognitive Radio Architectures for Spectrum Sensing

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    Recently, the growing success of new wireless applications and services has led to overcrowded licensed bands, inducing the governmental regulatory agencies to consider more flexible strategies to improve the utilization of the radio spectrum. To this end, cognitive radio represents a promising technology since it allows to exploit the unused radio resources. In this context, the spectrum sensing task is one of the most challenging issues faced by a cognitive radio. It consists of an analysis of the radio environment to detect unused resources which can be exploited by cognitive radios. In this paper, three different cognitive radio architectures, namely, stand-alone single antenna, cooperative and multiple antennas, are proposed for spectrum sensing purposes. These architectures implement a relatively fast and reliable signal processing algorithm, based on a feature detection technique and support vector machines, for identifying the transmissions in a given environment. Such architectures are compared in terms of detection and classification performances for two transmission standards, IEEE 802.11a and IEEE 802.16e. A set of numerical simulations have been carried out in a challenging scenario, and the advantages and disadvantages of the proposed architectures are discussed

    Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea)

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    The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae), is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800), showing the highest frequency of occurrence (69-100%), biomass (BI; 10-85 kg*km-2) and density (DI; 54-506 N*km-2) indexes in the deeper (501-800m) grounds. Individual size (total length, TL, mm) were between 70-590 and 90-510 in females and males, respectively. The sex ratio (SR) was around 0.5. The SR by size showed a gradual decrease till 450 mm class size, followed by an increase up 1 after 500 mm. Virginal/immature specimens represented the bulk of the samples in both females (77%) and males (65%); the length at 50% of sexual maturity (Lm50%) and corresponding maturity range (Lm25% - Lm75% ) was 433 (423-443) and 380 (366-394) mm, respectively

    TDEM for Martian in situ resource prospecting missions

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    This paper presents a TDEM (Time Domain Electromagnetic Methods) application, addressed to the search for water on Mars. In this context, the opportunities for a TDEM system as payload in a future mission are investigated for different in situ exploration scenarios. The TDEM sounding capability is evaluated with respect to the expected Martian environment, and some considerations are made about the many unknown variables (above all the background EM noise and the subsoil composition) altogether with the limited resources availability (mission constraints in mass, time and power) and the way they could represent an obstacle for operations and measurements

    Diet of a restocked population of the European pond turtle Emys orbicularis in NW Italy

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    Recently several projects have been implemented for the conservation of the European turtle Emys orbicularis, but few aspects of the captive-bred animals released into the wild have been described. In this note we report about the trophic habits of a small restocked population of the endemic subspecies E. o. ingauna that is now reproducing in NW Italy. Faecal contents from 25 individuals (10 females, 11 males and 4 juveniles) were obtained in June 2016. Overall, 11 taxonomic categories of invertebrates were identified, together with seeds and plant remains. Plant material was present in 24 out of 25 turtle faecal contents, suggesting that ingestion was deliberate. There were no differences between the dietary habits of females and males, and the trophic strategy of adult individuals was characterised by a relatively high specialization on dragonfly nymphae. These findings suggest that captive bred turtles are adapting well to the wild and that restocked individuals assumed an omnivorous diet, a trophic behaviour typical of other wild turtle populations living in similar habitats

    So close so different: what makes the difference?

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    The introduction of alien fish species in wetland ecosystems could have a great impact on freshwater communities and ecological processes. Despite fish introduction has been noticed as one of the principal cause of freshwater extinctions, ecosystem processes alteration, and change in aquatic community assemblage, very few data about impact on freshwater reptiles are available. As study model we used two neighbour sub-populations of the endangered Sicilian pond turtle, Emys trinacris, inhabiting two small, close each other and very similar lakes, except for the presence of allocthonous fish, Cyprinus carpio and Gambusia hoolbroki in one of the two. The multi-year study allowed highlighting significant differences in abundance, growth and reproductive output between the two freshwater turtle sub-populations, suggesting their influence on phenotypic plasticity of the studied population. These results are discussed in the light of previous evidence about the impact of these alien species on abundance and assemblage of the invertebrate community with an evident impact on niche width, diet composition and therefore energy intake by Emys trinacris. These data may provide important information to address management strategies and conservation actions of small wetland areas inhabited by pond turtles, pointing out a threats never highlighted up to now

    Mechanistic insights on the mode of action of an antiproliferative thiosemicarbazone-nickel complex revealed by an integrated chemogenomic profiling study

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    Thiosemicarbazones (TSC) and their metal complexes display diverse biological activities and are active against multiple pathological conditions ranging from microbial infections to abnormal cell proliferation. Ribonucleotide reductase (RNR) is considered one of the main targets of TSCs, yet, the existence of additional targets, differently responsible for the multifaceted activities of TSCs and their metal complexes has been proposed. To set the basis for a more comprehensive delineation of their mode of action, we chemogenomically profiled the cellular effects of bis(citronellalthiosemicarbazonato)nickel(II) [Ni(S-tcitr)2] using the unicellular eukaryote Saccharomyces cerevisiae as a model organism. Two complementary genomic phenotyping screens led to the identification of 269 sensitive and 56 tolerant deletion mutant strains and of 14 genes that when overexpressed make yeast cells resistant to an otherwise lethal concentration of Ni(S-tcitr)2. Chromatin remodeling, cytoskeleton organization, mitochondrial function and iron metabolism were identified as lead cellular processes responsible for Ni(S-tcitr)2 toxicity. The latter process, and particularly glutaredoxin-mediated iron loading of RNR, was found to be affected by Ni(S-tcitr)2. Given the multiple pathways regulated by glutaredoxins, targeting of these proteins by Ni(S-tcitr)2 can negatively affect various core cellular processes that may critically contribute to Ni(S-tcitr)2 cytotoxicity
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