Crown gall disease caused by the bacterium Agrobacterium tumefaciens can cause significant economic loss in both commercial walnut orchards and in nursery operations in California. This results from the fact that, Paradox, one of the most popular walnut rootstocks in California, is extremely susceptible to A. tumefaciens infection and Crown Gall formation. By combining direct soil-DNA extractio...

Abstract The combined effect of topography and near-surface heterogeneities on the seismic response is hardly predictable may lead to an aggravation ground motion. We apply physics-based numerical simulations 3D wave propagation highlight these effects in case study Arquata del Tronto, a municipality Apennines that includes historical village hill hamlet flat terrain alluvial basin. two hamlets...

The paper studies certain dynamic characteristics of soil deposits with wave velocities increasing with depth according to (l+pz)'", where m = 1, 2/3, 1/2, 1/4 and 0. Analytical solutions are presented for the fundamental periods, mode shapes and amplification functions due to vertically propagating shear waves and the effects of type (m) and rate ( p ) of heterogeneity are systematically inves...

The precise microenvironment of Paracoccidioides brasiliensis has not yet been discovered perhaps because the methods used are not sensitive enough. We applied to this purpose the polymerase chain reaction (PCR) using three sets of specific primers corresponding to two P. brasiliensis genes. This fungus as well as several other fungi, were grown and their DNA obtained by mechanical disruption a...

Based on the parallel computing cluster platform of the ABAQUS software, a large-scale 2D finite-element refined nonlinear modeling approach was used to study seismic site effects in the Fuzhou basin, such as peak ground acceleration (PGA), spectral acceleration, duration, and acceleration transfer functions. A 1D equivalent linear wave propagation analysis was conducted also, with Proshake for...

Decomposition of plant litter by the soil microbial community is an important process of controlling nutrient cycling and soil humus formation. Fungal laccases are key players in litter-associated polyphenol degradation, but little is known about the diversity and spatial distribution of fungal species with laccase genes in soils. Diversity of basidiomycete laccase genes was assessed in a cambi...

This brief article elaborates on some clearly unlikely predictions made some four decades ago by R. Dobry within the context of his doctoral dissertation, which concern the resonant frequencies of soil strata whose stiffness starts at zero at ground level and then increases continuously as some power of the depth. Although the problem was eventually traced to subtle changes in the boundary cond...

Prion interactions with soil may play an important role in the transmission of chronic wasting disease (CWD) and scrapie. Prions are known to bind to a wide range of soil surfaces, but the effects of adsorption solution chemistry and long-term soil binding on prion fate and transmission risk are unknown. We investigated HY TME prion protein (PrP(Sc)) adsorption to soil minerals in aqueous solut...

The study of free-living nitrogen-fixing organisms in bulk soil is hampered by the great diversity of soil microbial communities and the difficulty of relating nitrogen fixation activities to individual members of the diazotroph populations. We developed a molecular method that allows analysis of nifH mRNA expression in soil in parallel with determinations of nitrogen-fixing activity and bacter...