1,235 research outputs found
A Nonlocal Elasto-Plastic Model for Structured Soils at Large Strains for the Particle Finite Element Method
This work presents a robust and mesh-independent implementation of an elasto-plastic constitutive model at large strains, appropriate for structured soils, into a Particle Finite Element code specially developed for geotechnical simulations. The constitutive response of structured soils is characterized by softening and, thus, leading to strain localization. Strain localization poses two numerical challenges: mesh dependence of the solution and computability of the solution. The former is mitigated by employing a non-local integral type regularization whereas an Implicit-Explicit integration scheme is used to enhance the computability. The good performance of these techniques is highlighted in the simulation of the cone penetration test in undrained conditions.Peer ReviewedPostprint (published version
Biodegradation and metabolic pathway of the neonicotinoid insecticide thiamethoxam by Labrys portucalensis F11
Thiamethoxam (TMX) is an effective neonicotinoid insecticide. However, its widespread use is detrimental to non-targeted organisms and water systems. This study investigates the biodegradation of this insecticide by Labrys portucalensis F11. After 30 days of incubation in mineral salt medium, L. portucalensis F11 was able to remove 41%, 35% and 100% of a supplied amount of TMX (10.8 mg L−1) provided as the sole carbon and nitrogen source, the sole carbon and sulfur source and as the sole carbon source, respectively. Periodic feeding with sodium acetate as the supplementary carbon source resulted in faster degradation of TMX (10.8 mg L−1); more than 90% was removed in 3 days. The detection and identification of biodegradation intermediates was performed by UPLC-QTOF/MS/MS. The chemical structure of 12 metabolites is proposed. Nitro reduction, oxadiazine ring cleavage and dechlorination are the main degradation pathways proposed. After biodegradation, toxicity was removed as indicated using Aliivibrio fischeri and by assessing the synthesis of an inducible β-galactosidase by an E. coli mutant (Toxi-Chromo test). L. portucalensis F11 was able to degrade TMX under different conditions and could be effective in bioremediation strategies.info:eu-repo/semantics/publishedVersio
Bacterial strain labrys portucalensis F11 degrades the neonicotinoid insecticide thiamethoxam and removes toxicity
info:eu-repo/semantics/publishedVersio
Correlates of spinal deforming index (SDI) in HIV-positive patients naive and on treatment
Methods HIV-infected subjects naive or on stable HAART were included. Vertebral deformities were identified using SDI (according to semiquantitative method by Genant), calculated by summing the deformity grades of all vertebrae (T4 to L4); pathological deformities are defined as follow: grade 1 between 20–25%, grade 2 between 26–40%, and grade 3 > >40%. According to WHO criteria, osteopenia and osteoporosis were diagnosed in patients having spine BMD calculated as -1 << T-score << -2.5 and T-score ≤≤2.5, respectively. The correlation between SDI and spine BMD was evaluated by univariate and multivariate linear regression. [Other variables considered: gender, age, current CD4 count, CD4 nadir, BMI, lipid parameters, alcohol intake, smoking habit, physical activity, family history for bone fracture, months of ARV exposure, and co-infection with hepatitis viruses; only the variables with p <<0.2 in univariate analyses were included in the final model.
Chest pain and a left parasternal soft tissue swelling in an immunocompetent refugee with disseminated tuberculosis
An immunocompetent migrant with chest pain was admitted to an Italian hospital. CT scan showed a left pectoral abscess and osteomyelitis of the sternum. The infection spread into the anterior mediastinum near to the pericardium and the heart, where an atrial mass was confirmed by echocardiography. Disseminated tuberculosis was diagnosed
An in-depth view of the microscopic dynamics of Ising spin glasses at fixed temperature
Using the dedicated computer Janus, we follow the nonequilibrium dynamics of
the Ising spin glass in three dimensions for eleven orders of magnitude. The
use of integral estimators for the coherence and correlation lengths allows us
to study dynamic heterogeneities and the presence of a replicon mode and to
obtain safe bounds on the Edwards-Anderson order parameter below the critical
temperature. We obtain good agreement with experimental determinations of the
temperature-dependent decay exponents for the thermoremanent magnetization.
This magnitude is observed to scale with the much harder to measure coherence
length, a potentially useful result for experimentalists. The exponents for
energy relaxation display a linear dependence on temperature and reasonable
extrapolations to the critical point. We conclude examining the time growth of
the coherence length, with a comparison of critical and activated dynamics.Comment: 38 pages, 26 figure
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