Search results for "satellite"
showing 10 items of 1031 documents
Mitochondrial simple sequenze repeats and 12s – rRNA gene reveal two distinct lineages of Crocidura russula (Mammalia, Sorcidae)
2004
A short segment (135 bp) of the control region and a partial sequence (394 bp) of the 12S-rRNA gene in the mitochondrial DNA of Crocidura russula were analyzed in order to test a previous hypothesis regarding the presence of a gene flow disruption in northern Africa. This breakpoint would have separated northeast-African C. russula populations from the European (plus the northwest-African) populations. The analysis was carried out on specimens from Tunisia (C. r. cf agilis), Sardinia (C. r. ichnusae), and Pantelleria (C. r. cossyrensis), and on C. r. russula from Spain and Belgium. Two C. russula lineages were identified; they both shared R2 tandem repeated motifs of the same length (12 bp)…
Streaming for vehicular users via elastic proxy buffer management
2004
In this article we refer to the market of vehicular networks, where groups of customers located in the same public vehicle (e.g., a train or bus) connect to a terrestrial network through a wireless/satellite backbone link. Elastic buffering is a proxy management technique devised to decouple the multimedia information retrieval rate on the network backbone from the playout streaming rate at the user terminal. It has been shown in the past that the application of elastic buffering mechanisms in terrestrial networks brings significant advantages in terms of network effectiveness. We show that elastic buffering is an extremely effective means to reduce, or even eliminate, streaming service out…
Gain-of-function mutations in IFIH1 cause a spectrum of human disease phenotypes associated with upregulated type I interferon signaling.
2014
The type I interferon system is integral to human antiviral immunity. However, inappropriate stimulation or defective negative regulation of this system can lead to inflammatory disease. We sought to determine the molecular basis of genetically uncharacterized cases of the type I interferonopathy Aicardi-Goutières syndrome, and of other patients with undefined neurological and immunological phenotypes also demonstrating an upregulated type I interferon response. We found that heterozygous mutations in the cytosolic double-stranded RNA receptor gene IFIH1 (MDA5) cause a spectrum of neuro-immunological features consistently associated with an enhanced interferon state. Cellular and biochemica…
Isolation of the DNA minisatellite probe MZ 1.3 and its application to DNA ‘fingerprinting’ analysis
1990
Abstract A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53–73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI PvuII , and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 ± 7.2%. An examp…
Genetic variability and geographical diversity of the main Chagas' disease vector Panstrongylus megistus (Hemiptera: Triatominae) in Brazil based on …
2014
Studies were made on the ribosomal DNA intergenic region, comprising complete internal transcribed spacer (ITS)-1, 5.8S, and ITS-2 sequences, of populations of the triatomine Panstrongylus megistus, the most important vector of Chagas' disease in Brazil since Triatoma infestans eradication. Specimens were from 26 localities of Rio Grande do Sul, Santa Catarina, Paraná, São Paulo, Minas Gerais, Bahia, and Sergipe states. In total, 21 ITS-1 and 12 ITS-2 haplotypes were found. Nucleotide differences were higher in ITS-1 (3.00%) than in ITS-2 (1.33%). The intergenic region was 1,513-1,522-bp-long (mean 1,516.9 bp), providing 26 combined haplotypes. The combination of microsatellites found in bo…
In vitro anther culture of sweet orange (Citrus sinensis L. Osbeck) genotypes and of a C. clementina × C. sinensis 'Hamlin' hybrid
2014
Citrus, and particularly sweet oranges, are very recalcitrant to anther culture. In this paper it was evaluated for the first time the response of 27 genotypes of Citrus sinensis and of one hybrid C. clementina × C. sinensis, to in vitro anther culture. Ten genotypes of sweet oranges showed embryogenic callus induction, mostly blood sweet oranges genotypes, such as Tarocco, Moro and Sanguinelli. In vitro microspore developmental switches from the gamethophytic to the sporophytic pathway were shown by DAPI staining in microspores of these responsive genotypes, after 10 months in culture. However, microsatellite marker analyses showed that these calli were heterozygous. The flow-cytometric an…
Modelling of ERS-2 radar backscattering over rocky arid regions
2003
This paper discusses the potential of radar signals to characterize stone cover over bare soil surfaces in arid rocky regions. Ground truth and radar measurements were made over two arid sites: Avdat (Israel) and Foumtillich (Morocco). An empirical approach is proposed to derive stone cover percentage from pin profiler measurements. A numerical Moment method based on integral equations of backscattering has been used to study the influence of stone cover on simulated radar signal. The results of the simulations are compared with European Remote Sensing Satellite (ERS-2) radar measurements over test areas with different stone covers. Excellent agreement is observed between numerical simulati…
A satellite stand-alone procedure for deriving net radiation by using SEVIRI and MODIS products
2018
Abstract In this study, a new stand-alone satellite approach for the estimation of net surface radiation (Rn) has been implemented and validated for the Italian territory. The method uses the MODIS and MSG-SEVIRI time series products and it is independent of the use of ancillary data (i.e. ground measurements). A database of daily measurements of Rn, provided by 9 stations of the FLUXNET network, was used to validate the method in different ecological scenarios in the period 2010-12. The Rn modelled by the proposed approach and the corresponding FLUXNET measurements were in good agreement, with RMSE and R2 of 19.8 Wm−2 and 0.87, respectively, at 8-days scale, and 23.3 Wm−2 and 0.92, respect…
Life in the Solar System?
2010
Europa, the smallest of the four moons of Jupiter discovered by Galileo Galilei, has attracted much speculation on whether it might be inhabited ever since it was observed by the Voyager probes. This is mostly due to the fact that water, or better said, water-ice, is the most evident feature of that world, with ice covering this interesting satellite completely, turning it into a smooth white ball.
Differential Greek and northern African migrations to Sicily are supported by genetic evidence from the Y chromosome
2009
The presence or absence of genetic heterogeneity in Sicily has long been debated. Through the analysis of the variation of Y-chromosome lineages, using the combination of haplogroups and short tandem repeats from several areas of Sicily, we show that traces of genetic flows occurred in the island, due to ancient Greek colonization and to northern African contributions, are still visible on the basis of the distribution of some lineages. The genetic contribution of Greek chromosomes to the Sicilian gene pool is estimated to be about 37% whereas the contribution of North African populations is estimated to be around 6%. In particular, the presence of a modal haplotype coming from the southern…