A systematic theory to describe the anisotropic damage states of materials and a consistent definition of effective stress tensors are developed within the framework of continuum damage mechanics. By introducing a fictitious undamaged configuration, mechanically equivalent to the real damaged configuration, the classical creep damage theory is extended to the general three-dimensional states of material damage; it is shown that the damage state can be described in terms of a symmetric second rank tensor. The physical implications, mathematical restrictions, and the limitations of this damage tensor, as well as the effects of finite deformation on the damage state, are discussed in some detail. The notion of the fictitious undamaged configuration is then applied also to the definition of effective stresses. Finally, the extension of the effective stresses incorporating the effects of crack closure is discussed. The resulting effective stress tensor is employed to analyze the stress-path dependence of the elastic behavior of a cracked elastic-brittle material.

Bismuth ferrite-based lead-free multilayers with a high recoverable energy density of 6.74 J cm−3 and an efficiency of 77%, stable up to 125 °C.

No abstract

No abstract

In the PACIFIC trial, durvalumab significantly improved progression-free and overall survival (PFS/OS) versus placebo, with manageable safety, in unresectable, stage III non-small-cell lung cancer (NSCLC) patients without progression after chemoradiotherapy (CRT). We report exploratory analyses of outcomes by tumour cell (TC) programmed death-ligand 1 (PD-L1) expression. Patients and methods: Patients were randomly assigned (2:1) to intravenous durvalumab 10 mg/kg every 2 weeks or placebo 12 months, stratified by age, sex, and smoking history, but not PD-L1 status. Where available, pre-CRT samples were tested for PD-L1 expression (immunohistochemistry) and scored at pre-specified (25%) and post hoc (1%) TC cut-offs. Treatment-effect hazard ratios (HRs) were estimated from unstratified Cox proportional hazards models (KaplaneMeier-estimated medians). Results: In total, 713 patients were randomly assigned, 709 of whom received at least 1 dose of study treatment durvalumab (n ¼ 473) or placebo (n ¼ 236). Some 451 (63%) were PD-L1-assessable: 35%, 65%, 67%, 33%, and 32% had TC !25%, <25%, !1%, <1%, and 1%e24%, respectively. As of 31 January 2019, median follow-up was 33.3 months. Durvalumab improved PFS versus placebo (primary-analysis data cut-off, 13 February 2017) across all subgroups [HR, 95% confidence interval (CI); medians]: TC !25% (0.41, 0.26e0.65; 17.8 versus 3.7 months), <25% (0.59, 0.43e0.82; 16.9 versus 6.9 months), !1% (0.46, 0.33e0.64; 17.8 versus 5.6 months), <1% (0.73, 0.48e1.11; 10.7 versus 5.6 months), 1%e24% [0.49, 0.30e0.80; not reached (NR) versus 9.0 months], and unknown (0.59, 0.42 e0.83; 14.0 versus 6.4 months). Durvalumab improved OS across most subgroups (31 January 2019 data cut-off; HR, 95% CI; medians): TC ! 25% (0.50, 0.30e0.83; NR versus 21.1 months), <25% (0.89, 0.63e1.25; 39.7 versus 37.4 months), !1% (0.59, 0.41e0.83; NR versus 29.6 months), 1%e24% (0.67, 0.41e1.10; 43.3 versus 30.5 months), and unknown (0.60, 0.43e0.84; 44.2 versus 23.5 months), but not <1% (1.14, 0.71e1.84; 33.1 versus 45.6 months). Safety was similar across subgroups. Conclusions: PFS benefit with durvalumab was observed across all subgroups, and OS benefit across all but TC <1%, for which limitations and wide HR CI preclude robust conclusions.