Resposta de tangerinas e híbridos ao virus da leprose dos citros.

A leprose dos citros é uma das mais importantes viroses da citricultura brasileira. A doença, causada pelo Citrus leprosis virus C (CiLV-C) transmitido por Brevipalpus phoenicis, caracteriza-se pela indução de lesões locais no hospedeiro vegetal. Por ser uma virose não sistêmica, ao contrário da maioria das que ocorrem em plantas, o conhecimento dos mecanismos envolvidos nas interações vírus x planta x vetor se tornam ainda mais importantes, principalmente em relação ao manejo da doença no campo.A leprose tem a sua maior importância econômica no Brasil, embora relatos de sua ocorrência em países das Américas vêm aumentando significativamente nos últimos anos (Bastianel et al., 2010). Por ser um sério problema fitossanitário em pomares de laranjas doces, graças ao plantio em grande escala de variedades altamente suscetíveis, poucos estudos sobre a importância da leprose em outros grupos de citros, como as tangerinas e tangores têm sido relatados. Neste trabalho, estudos foram conduzidos com o objetivo de se ampliar o conhecimento da resposta da doença em variedades de tangerinas e híbridos de importância econômica.pdf 145

Near-field propagation of tsunamis from megathrust earthquakes

We investigate controls on tsunami generation and propagation in the near-field of great megathrust earthquakes using a series of numerical simulations of subduction and tsunamigenesis on the Sumatran forearc. The Sunda megathrust here is advanced in its seismic cycle and may be ready for another great earthquake. We calculate the seafloor displacements and tsunami wave heights for about 100 complex earthquake ruptures whose synthesis was informed by reference to geodetic and stress accumulation studies. Remarkably, results show that, for any near-field location: (1) the timing of tsunami inundation is independent of slipdistribution on the earthquake or even of its magnitude, and (2) the maximum wave height is directly proportional to the vertical coseismic displacement experienced at that location. Both observations are explained by the dominance of long wavelength crustal flexure in near-field tsunamigenesis. The results show, for the first time, that a single estimate of vertical coseismic displacement might provide a reliable short-term forecast of the maximum height of tsunami waves

Synthesis and coordination chemistry of 2-(di-2-pyridylamino)pyrimidine; structural aspects of spin crossover in an Fe(II) complex

This paper was accepted on February 26 20122-(Di-2-pyridylamino)pyrimidine (L), a potentially ditopic tetradentate ligand, was synthesized from commercially available di-2-pyridylamine and 2-chloropyrimidine. Despite being capable of bridging two metal atoms with bidentate chelation of both metal centres, L prefers to chelate or bridge through the more basic pyridyl donors of the di-2-pyridylamine moiety. Mononuclear trans-[Fe(NCS)2(L)2] and [Cu(L)2(H2O)](BF4)2•H2O complexes, and a discrete [Ag2(L)4](PF6)2 metallomacrocycle were isolated and structurally characterized by X-ray crystallography. A mononuclear palladium complex [PdCl2(L)]•(solvate), where solvate = ½H2O or CH2Cl2, was also readily obtained in 71% yield. One example of the ligand acting as a bis(bidentate) bridging ligand was observed in a dinuclear [(PdCl2)2(L)]•¾H2O complex that was obtained only in very low yield (ca. 3%) from the reaction that produced [PdCl2(L)]•½H2O. trans-[Fe(NCS)2(L)2] undergoes a temperature dependent HS-LS (HS = high spin; LS = low spin) crossover at ca. 205 K that was 2 observed by X-ray crystallography and magnetic measurements and attempts were made to understand the structural basis of this process. Despite efforts to isolate examples of L bridging two iron(II) centres, only the mononuclear trans-[Fe(NCS)2(L)2] species could be obtained.Rachel S. Crees, Boujemma Moubaraki, Keith S. Murray, and Christopher J. Sumb

Activation of the SIGRIS monitoring system for ground deformation mapping during the Emilia 2012 seismic sequence, using COSMO-SkyMed InSAR data

On May 20, 2012, at 02:03 UTC, a moderate earthquake of local magnitude, ML 5.9 started a seismic sequence in the central Po Plain of northern Italy (Figure 1) [Scognamiglio et al. 2012, this volume]. The mainshock occurred in an area where seismicity of comparable magnitude has neither been recorded nor reported in the historical record over the last 1,000 years [Rovida et al. 2011]. The aftershock sequence evolved rapidly near the epicenter, with diminishing magnitudes until May 29, 2012, when at 07:00 UTC a large earthquake of ML 5.8 occurred 12 km WSW of the mainshock, starting a new seismic sequence in the western area (Figure 1); a total of seven earthquakes with ML >5 occurred in the area between May 20 and June 3, 2012 (Figure 1). The details of the seismic sequence can be found in the report by Scognamiglio et al. [2012]. Immediately after the mainshock, the Italian Department of Civil Protection (Dipartimento di Protezione Civile; DPC) requested the Italian Space Agency (Agenzia Spaziale Italiana; ASI) to activate the Constellation of Small Satellites for Mediterranean Basin Observation (COSMOSkyMed) to provide Interferometric Synthetic Aperture Radar (InSAR) coverage of the area. COSMO-SkyMed consists of four satellites in a 16-day repeat-pass cycle, with each carrying the same SAR payload [Italian Space Agency 2007]. In the current orbital configuration, within each 16- day cycle, image pairs with temporal baselines of 1, 3, 4 and 8 days can be formed from the images acquired by the four different sensors. Combined with the availability of a wide range of electronically steered antenna beams with incidence angles ranging from about 16° to 50° at near-range [E-geos 2012], this capability allows trade-offs between temporal and spatial coverage to be exploited during acquisition planning. A joint team involving the Istituto Nazionale di Geofisica e Vulcanologia (INGV; National Institute of Geophysics and Volcanology) and the Istituto per il Rilevamento Elettromagnetico dell'Ambiente (IREA-CNR; Institute for the Electromagnetic Sensing of the Environment) was activated to generate InSAR-based scientific products to support the emergency management. In this framework, the ASI and DPC requested that INGV activated the Spacebased Monitoring System for Seismic Risk Management (SIGRIS) [Salvi et al. 2010]. SIGRIS consists of a hardware/ software infrastructure that is designed to provide the DPC with value-added information products in the different phases of the seismic cycle. During earthquake emergencies, its goal is to rapidly provide decision-support products, such as validated ground-displacement maps and seismic source models. This study reports the details of the activation of the SIGRIS system in the case of the Emilia sequence. It provides a description of the COSMO-SkyMed datasets and processing procedures, as well as selected interferometric results for the coseismic and post-seismic ground deformation. Fault modeling results for the seismic sources of the largest earthquakes, and a more detailed discussion of the observed ground deformations are reported in Pezzo et al. [2012]

Searching for prompt signatures of nearby core-collapse supernovae by a joint analysis of neutrino and gravitational-wave data

We discuss the science motivations and prospects for a joint analysis of gravitational-wave (GW) and low-energy neutrino data to search for prompt signals from nearby supernovae (SNe). Both gravitational-wave and low-energy neutrinos are expected to be produced in the innermost region of a core-collapse supernova, and a search for coincident signals would probe the processes which power a supernova explosion. It is estimated that the current generation of neutrino and gravitational-wave detectors would be sensitive to Galactic core-collapse supernovae, and would also be able to detect electromagnetically dark SNe. A joint GW-neutrino search would enable improvements to searches by way of lower detection thresholds, larger distance range, better live-time coverage by a network of GW and neutrino detectors, and increased significance of candidate detections. A close collaboration between the GW and neutrino communities for such a search will thus go far toward realizing a much sought-after astrophysics goal of detecting the next nearby supernova.Comment: 10 pages, 3 figures. To appear in Class. Quantum Gra

Coseismic deformation and source modeling of the May 2012 Emilia (Northern Italy) earthquakes

On May 20th, 2012, an ML 5.9 earthquake (Table 1) occurred near the town of Finale Emilia, in the Central Po Plain, Northern Italy (Figure 1). The mainshock caused 7 casualties and the collapse of several historical buildings and industrial sheds. The earthquake sequence continued with diminishing aftershock magnitudes until May 29th, when an ML 5.8 earthquake occurred near the town of Mirandola, ~12 km WSW of the mainshock (Scognamiglio et al., 2012). This second mainshock started a new aftershock sequence in this area, and increased structural damage and collapses, causing 19 more casualties and increasing to 15.000 the number of evacuees. Shortly after the first mainshock, the Department of Civil Protection (DPC) activated the Italian Space Agency (ASI), which provided post-seismic SAR Interferometry data coverage with all 4 COSMO-SkyMed SAR satellites. Within the next two weeks, several SAR Interferometry (InSAR) image pairs were processed by the INGV-SIGRIS system (Salvi et al., 2012), to generate displacement maps and preliminary source models for the emergency management. These results included continuous GPS site displacement data, from private and public sources, located in and around the epicentral area. In this paper we present the results of the geodetic data modeling, identifying two main fault planes for the Emilia seismic sequence and computing the corresponding slip distributions. We discuss the implication of this seismic sequence on the activity of the frontal part of the Northern Apennine accretionary wedge by comparing the co-seismic data with the long term (geological) and present day (GPS) velocity fields.Published645-6551.1. TTC - Monitoraggio sismico del territorio nazionale1.9. Rete GPS nazionale1.10. TTC - Telerilevamento3.2. Tettonica attivaJCR Journalrestricte

Low Multiplicity Burst Search at the Sudbury Neutrino Observatory

Results are reported from a search for low-multiplicity neutrino bursts in the Sudbury Neutrino Observatory (SNO). Such bursts could indicate detection of a nearby core-collapse supernova explosion. The data were taken from Phase I (November 1999 - May 2001), when the detector was filled with heavy water, and Phase II (July 2001 - August 2003), when NaCl was added to the target. The search was a blind analysis in which the potential backgrounds were estimated and analysis cuts were developed to eliminate such backgrounds with 90% confidence before the data were examined. The search maintained a greater than 50% detection probability for standard supernovae occurring at a distance of up to 60 kpc for Phase I and up to 70 kpc for Phase II. No low-multiplicity bursts were observed during the data-taking period.Comment: 11 pages, 4 figures, submitted to Ap

Multijet production in neutral current deep inelastic scattering at HERA and determination of α_{s}

Multijet production rates in neutral current deep inelastic scattering have been measured in the range of exchanged boson virtualities 10 5 GeV and –1 < η_{LAB}^{jet} < 2.5. Next-to-leading-order QCD calculations describe the data well. The value of the strong coupling constant α_{s} (M_{z}), determined from the ratio of the trijet to dijet cross sections, is α_{s} (M_{z}) = 0.1179 ± 0.0013 (stat.)_{-0.0046}^{+0.0028}(exp.)_{-0.0046}^{+0.0028}(th.)