Large-scale numerical modeling of hydro-acoustic waves generated by tsunamigenic earthquakes

Abstract. Tsunamigenic fast movements of the seabed generate pressure waves in weakly compressible seawater, namely hydro-acoustic waves, which travel at the sound celerity in water (about 1500 m s−1). These waves travel much faster than the counterpart long free-surface gravity waves and contain significant information on the source. Measurement of hydro-acoustic waves can therefore anticipate the tsunami arrival and significantly improve the capability of tsunami early warning systems. In this paper a novel numerical model for reproduction of hydro-acoustic waves is applied to analyze the generation and propagation in real bathymetry of these pressure perturbations for two historical catastrophic earthquake scenarios in Mediterranean Sea. The model is based on the solution of a depth-integrated equation, and therefore results are computationally efficient in reconstructing the hydro-acoustic waves propagation scenarios

Primary cosmic ray spectrum in the 10 to the 12th power - 10 to the 16th power eV energy range from the NUSEX experiment

A primary cosmic ray spectrum was derived which fits both experimental multiple muon rates and the all-nucleon flux derived from the single muon intensities underground. In the frame of the interaction model developed by Gaisser, Elbert and Stanev, it is possible to reproduce NUSEX muon data with a primary composition in which the iron spectrum is only slightly flatter than the proton one. This result rules out the popular idea that the primary composition varies drastically with increasing energy, leading to the dominance of heavier nuclei at energies 10 to the 15th power to 10 to the 16th power eV

Nucleon decay and atmospheric neutrinos in the Mont Blanc experiment

In the NUSEX experiment, during 2.8 years of operation, 31 fully contained events have been collected; 3 among them are nucleon decay candidates, while the others have been attributed to upsilon interactions. Limits on nucleon lifetime and determinations of upsilon interaction rates are presented

Real-time inversion of tsunamis generated by landslides

Abstract. In this paper, we test a method for forecasting in real-time the properties of offshore propagating tsunami waves generated by landslides, with the aim of supporting tsunami early warning systems. The method uses an inversion procedure, that takes input data measurements of water surface elevation at a point close to the tsunamigenic source. The measurements are used to correct the results of pre-computed numerical simulations, reproducing the wave field induced by different landslide scenarios. The accuracy of the method is evaluated using the results of laboratory experiments, aimed at studying tsunamis generated by landslides sliding along the flank of a circular shoreline island. The paper investigates what the optimal position is of where to measure the tsunamis, what the effects are, the accuracy of the results, and of uncertainties on the landslide scenarios. Finally, the method is successfully tested using partial input time series, simulating the behaviour of the system in real-time during the tsunami event when forecasts are updated, as the measurements become available

Resistance to the Whitefly, Aleurotrachelus socialis, in Wild Populations of Cassava, Manihot Tristis

The levels of resistance in the wild species of cassava, Manihot tristis Muell-Arg. (Malpighiales: Euphorbiaceae), to the whitefly, Aleurotrachelus socialis Bondar (Hemiptera: Alelyrodidae), the most important economic pest in cassava, Manihot esculenta Crantz (Malpighiales: Euphorbiaceae) crops in South America, were estimated under glasshouse conditions. The parameters of the life history of A. socialis were studied on TST-26 and TST-18 accessions of the wild parent and compared with the susceptible (CMC-40) and resistant (MEcu-72) cultivars. The average longevity on the wild accessions (TST-26, 4.1; TST-18, 4.6 days) and oviposition rates (TST-26, 2.0; TST-18, 1.6 eggs/female/2 days) of the A. socialis females were not significantly different from those of MEcu-72 (5.1 days and 3.4 eggs/female/2days). The longevity and oviposition rates on CMC-40 were highest (11 days and 8.6 eggs/female/2days). Analyses of the demographic parameters (Ro, rm; DT) showed a significant impact of the M. tristis accessions on the potential growth of A. socialis. The average survival time of adults that fed on TST-26, TST-18, and MEcu-72 were significantly different from those recorded on the susceptible genotype. Results from this study revealed important levels of resistance to the whitefly A. socialis on the TST-26 and TST-18 accessions due to the marked differences found for longevity and reproduction, which influenced and were consistent with the differences found in the net reproduction rate (Ro), intrinsic growth rate (rm) and population doubling time (DT). The combined effect of these parameters indicated that M. tristis accessions were inappropriate hosts for A. socialis

Avaliação de híbridos interespecíficos de mandioca para a resistência a doenças.

Este trabalho objetivou a avaliação da incidência e severidade de doenças em híbridos interespecíficos de mandioca em diferentes localidades do Nordeste brasileiro

Avaliação de híbridos interespecíficos de mandioca para resistência a artrópodes-praga em condições semi-áridas.

Este trabalho foi conduzido utilizando-se híbridos interespecíficos de mandioca obtidos de cruzamentos entre espécies silvestres selecionadas e variedades elites de Manihot esculenta, com o objetivo de identificar genes exóticos relacionados à resistência às principais pragas que ocorrem na região semi-árida do Brasil.Edição dos resumos do XII Congresso Brasileiro de Mandioca na Revista Raízes e Amidos Tropicais, v. 3, out. 2007