3,450 research outputs found

    Strategies for achieving sustainable logging rate in the Brazilian Amazon Forest.

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    Data of increment of the remnant trees after logging, ingrowth and mortality was obtained by assessment before logging and after 6 years, two sites of 50 ha, in Amazon forest. Logging scenarios were simulated to identify the logging rate potential for each studying sites, by diameter class projection method. The cy- cle of 35 years and the logging rate of 30 m3?ha?1 exceed the time required for recovery in the primary forest, in the studied site. The simulation showed that in the studying area, a well-planned logging, with minimum logging damage would be possible to implement an initial cycle of 25 years to the forest to re- cover 30 m3?ha?1, if 50% of the timber stock were reserved. The forest increment, beyond important fac- tors such as the increase of individual species, is quite dependent on the remnant trees

    Produção de antissoro policlonal utilizando a proteína capsidial recombinante do Rupestris stem pitting-associated virus.

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    O Rupestris stem pitting-associated virus (RSPaV) é o agente causal das caneluras do lenho da videira. Este trabalho teve como objetivo produzir antissoro policlonal a partir da proteína capsidial (CP) recombinante do RSPaV e avaliar a sua especificidade e sensibilidade. O gene da CP do RSPaV, com 780pb, foi previamente caracterizado. Esse gene foi subclonado no sítio de restrição EcoRI, no vetor de expressão pRSET-B e o plasmídeo recombinante foi utilizado para induzir a expressão da CP em Escherichia coli. A CP, ligada a uma cauda de seis histidinas, foi purificada por meio de cromatografia de afinidade em coluna de Ni-NTA a partir do extrato de proteínas totais extraídas de E. coli. A identidade da proteína purificada foi confirmada em SDS-PAGE e Western blot, utilizando-se anticorpos comerciais contra a cauda de seis histidinas. A CP recombinante expressada in vitro apresentou massa molecular de cerca de 31kDa. A proteína purificada foi quantificada e 2,55mg foram utilizados para a imunização de um coelho. O antissoro policlonal obtido reagiu com diferentes isolados deste vírus, extraídos de videiras em ELISA indireto.Nota técnica

    Drug resistance in B and non-B subtypes amongst subjects recently diagnosed as primary/recent or chronic HIV-infected over the period 2013–2016: Impact on susceptibility to first-line strategies including integrase strand-transfer inhibitors

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    Objectives To characterize the prevalence of transmitted drug resistance mutations (TDRMs) by plasma analysis of 750 patients at the time of HIV diagnosis from January 1, 2013 to November 16, 2016 in the Veneto region (Italy), where all drugs included in the recommended first line therapies were prescribed, included integrase strand transfer inhibitors (InNSTI). Methods TDRMs were defined according to the Stanford HIV database algorithm. Results Subtype B was the most prevalent HIV clade (67.3%). A total of 92 patients (12.3%) were expected to be resistant to one drug at least, most with a single class mutation (60/68–88.2% in subtype B infected subjectsand 23/24–95.8% in non-B subjects) and affecting mainly NNRTIs. No significant differences were observed between the prevalence rates of TDRMs involving one or more drugs, except for the presence of E138A quite only in patients with B subtype and other NNRTI in subjects with non-B infection. The diagnosis of primary/recent infection was made in 73 patients (9.7%): they had almost only TDRMs involving a single class. Resistance to InSTI was studied in 484 subjects (53 with primary-recent infection), one patient had 143C in 2016, a total of thirteen 157Q mutations were detected (only one in primary/recent infection). Conclusions Only one major InSTI-TDRM was identified but monitoring of TDRMs should continue in the light of continuing presence of NNRTI-related mutation amongst newly diagnosed subjects, sometime impacting also to modern NNRTI drugs recommended in first-line therapy

    Manejo florestal no Mato Grosso.

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    bitstream/item/97490/1/CT-329-Evaldo.pd

    Compensation of B-L charge of matter with relic sneutrinos

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    We consider massless gauge boson connected to B-L charge with and without compensation to complete the investigation of the gauging of B and L charges. Relic sneutrinos predicted by SUSY and composite models may compensate B-L charge of matter. As a consequence of the possible compensation mechanism we have shown that the available experimental data admit the range of the B-L interaction constant, 10^{-29} < {\alpha}_{B-L} < 10^{-12}, in addition to {\alpha}_{B-L} < 10^{-49} obtained without compensation.Comment: 6 page

    Estudo do sistema de exploração florestal relativo ao manejo empresarial, no Estado de Mato Grosso.

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    bitstream/item/36429/1/CT261.pd

    The imaging properties of the Gas Pixel Detector as a focal plane polarimeter

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    X-rays are particularly suited to probe the physics of extreme objects. However, despite the enormous improvements of X-ray Astronomy in imaging, spectroscopy and timing, polarimetry remains largely unexplored. We propose the photoelectric polarimeter Gas Pixel Detector (GPD) as an instrument candidate to fill the gap of more than thirty years of lack of measurements. The GPD, in the focus of a telescope, will increase the sensitivity of orders of magnitude. Moreover, since it can measure the energy, the position, the arrival time and the polarization angle of every single photon, allows to perform polarimetry of subsets of data singled out from the spectrum, the light curve or the image of source. The GPD has an intrinsic very fine imaging capability and in this work we report on the calibration campaign carried out in 2012 at the PANTER X-ray test facility of the Max-Planck-Institut f\"ur extraterrestrische Physik of Garching (Germany) in which, for the first time, we coupled it to a JET-X optics module with a focal length of 3.5 m and an angular resolution of 18 arcsec at 4.5 keV. This configuration was proposed in 2012 aboard the X-ray Imaging Polarimetry Explorer (XIPE) in response to the ESA call for a small mission. We derived the imaging and polarimetric performance for extended sources like Pulsar Wind Nebulae and Supernova Remnants as case studies for the XIPE configuration, discussing also possible improvements by coupling the detector with advanced optics, having finer angular resolution and larger effective area, to study with more details extended objects.Comment: Accepted for publication in The Astrophysical Journal Supplemen
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