The availability of Roundup Ready (RR) varieties of soybean has increased the use of glyphosate for weed control in Argentina. Glyphosate [(N-phosphonomethyl)glycine] is employed for the eradication of previous crop vegetation and for weed control during the soybean growing cycle. Its action is effective, and low environmental impact has been reported so far. No residues have been observed in soil or water, either of glyphosate or its metabolite, AMPA (aminomethylphosphonic acid). The objective of this work was to monitor glyphosate and AMPA residues in soybean plants and grains in field crops in Santa Fe Province, Argentina. Five sites were monitored in 1997, 1998 and 1999. Individual soybean plants were sampled from emergence to harvest, dried and ground. Analysis consisted in residue extraction with organic solvents and buffers, agitation, centrifugation, clean-up and HPLC with UV detection. In soybean leaves and stems, glyphosate residues ranged from 1.9 to 4.4 mg kg(-1) and from 0.1 to 1.8 mg kg(-1) in grains. Higher concentrations were detected when glyphosate was sprayed several times during the crop cycle, and when treatments approached the flowering stage. AMPA residues were also detected in leaves and in grains, indicating metabolism of the herbicide.

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An orthotropic damage model specifically developed for the analysis of brittle masonry subjected to in-plane loading is described. Four independent internal damage parameters, one in compression and one in tension for each of the two natural axes of the masonry, are defined allowing the stiffness recovery at crack closure as well as the different inelastic behaviour along each natural axis to be considered. The damage field of the material is defined in terms of four equivalent stresses and results, in the space of the in-plane effective stresses, in a double pyramid with a rectangular base where the slopes of the faces correspond to the internal friction angle of the material. The equivalent stresses also control the growth of the damage parameters. The returning path from the effective to the damaged stresses is given by multiplication by a fourth-rank damage effect tensor, which is a function of the damage parameters and of the effective stress state. Mesh size regularization is achieved by means of an enhanced local method taking into account the finite element size. Good agreement has been found in the comparison between numerical results and experimental data both for masonry shear panels and for a large-scale masonry holed wall

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These results indicate that chlorantraniliprole has toxicity against S. cosmioides larvae. Sublethal effects on the biological and reproductive performance of this species can help optimize integrated pest management programs. © 2018 Society of Chemical Industry.

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Four massive wooden shear walls were analysed via experimental tests and numerical simulations. The specimens differ mainly in the method used to assemble the layers of timber boards: two of them are the well-known Cross-Laminated-Timber panels with glued interfaces, the other two are innovative massive timber panels adopting steel staples or wooden dovetail inserts to connect the layers. Quasi-static cyclic-loading tests were performed for each wall and main results are presented and analysed. A non-linear numerical model was calibrated on experimental results and used to perform non-linear dynamic analyses on specifically designed three-storey shear wall. The methods ensuring a reliable estimation of the intrinsic behaviour factor are presented and the definition of yielding and failure condition is discussed. The intrinsic behaviour factor values were calculated using results from non-linear dynamic analyses. Three limits of failure condition were analysed to estimate the correlated Peak Ground Acceleration and therefore the behaviour factor. A final interpretation of the obtained results is presented and some instructions about the choice of the suitable behaviour factor are given

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