In this paper, a multi-surface anisotropic constitutive model is proposed for clayey soils, based on bounding surface theory and a classical anisotropic critical state-based model. In the proposed model, in addition t...
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In this paper, a multi-surface anisotropic constitutive model is proposed for clayey soils, based on bounding surface theory and a classical anisotropic critical state-based model. In the proposed model, in addition to the volumetric hardening law, a rotational hardening rule is also incorporated into the bounding surface formulation with a non-associated flow rule. The model uses the bounding surface plasticity theory to produce a more realistic representation of the nonlinear behavior of clays with high overconsolidation ratios. Detailed model formulation is presented including an innovative approach to find image stress points on the bounding surface which offers an original conception of changing the projection center, even at the absence of plastic loading. A modified procedure is also discussed to improve the performance of the proposed model for simulating the response of highly overconsolidated clays. The proposed modifications, together with the novel mapping rule, form a new framework that can be used to improve the simulation capabilities of different constitutive models that have elliptical yield/bounding surfaces. The efficiency of the framework is demonstrated by comparing the simulation results against element test data from a number of different clays at lightly to highly overconsolidated conditions. The new model shows promising capabilities in capturing the important aspects of natural clays response during straining, in particular for the combined effects of small strain nonlinearity with fabric orientation.
Candida albicans is one of the most frequent pathogens present in the reproductive system. The negative in vitro effects of C. albicans on sperm functions have previously been studied. The current study was undertaken...
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Candida albicans is one of the most frequent pathogens present in the reproductive system. The negative in vitro effects of C. albicans on sperm functions have previously been studied. The current study was undertaken to investigate the effects of C. albicans infection in vivo on sperm quality and to evaluate the efficacy of vitamin E administration in rats infected with C. albicans. In this study, 5 days after infection induction, animals were treated with vitamin E for 5 weeks. Thereafter, sperm parameters, lipid peroxidation (LPO), total antioxidant capacity (TAC), hormonal analysis and testis histology were evaluated. Based on the results, sperm parameters and TAC significantly reduced, while LPO and tissue damage increased (p <= .05) following the infection. Hormone analysis showed low LH and testosterone levels in serum of the infected rats. Treatment with vitamin E significantly (p <= .05) improved sperm quality and testis histology, increased TAC and reduced LPO. In addition, vitamin E administration significantly increased (p <= .05) serum LH and testosterone levels. These results clearly indicate that vitamin E is effective in attenuating the adverse effects of C. albicans infection on male fertility and could be used as a complementary treatment for patients who suffer from fertility disorders following C. albicans infection.
We present a thermal evolution model coupled with a Henyey solver to study the circumstances under which a rocky planet could potentially host a dynamo in its liquid iron core and/or magma ocean. We calculate the evol...
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