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Superior mechanical response of twinnable materials fundamentally arises from an elevation of Critical Resolved Shear Stresses (CRSS) due to Dislocation-Twin Boundary (D-TB) reactions. These reactions exhibit rich variety with several possible outcomes and exhibit complex dependence on microstructural properties, causing state-of-the-art models to adopt a case-by-case simulation of each reaction relying on empirical potentials or twin-interaction parameters. We develop an analytical “Evolving Dislocation Core” (EDC) model devoid of empiricism, capable of predicting the CRSS-elevation for any reaction, given the microstructural properties (elastic constants, twin crystallography, etc.). The approach is fundamentally rooted in energy-minimization within a fully-anisotropic framework revealing the evolution of dislocation cores with progression of the reaction. The core-structure of complex dislocations (e.g. stair-rod) in the reaction is proposed, for the first time in literature, as a non-planar composite of disregistries distributed on slip and twin planes. The model is applied to multiple slip-incorporation reactions in several Face-Centered-Cubic (FCC) materials (Pb, Ag, Cu, Ni-Co alloys and Ni-Ti alloys and high-entropy alloy FeNiCoCrMn). The predicted CRSS-elevations show agreement with atomistic simulations (Ni) and experiment (FeNiCoCrMn). The model further establishes a strong correlation of the elevation with unstable stacking/twinning fault energy and the magnitude of the sessile dislocation's Burgers vector, while revealing poor correlation with the stable intrinsic stacking fault energy which is a common benchmark. Thus the analytical EDC model developed in this study advances understanding of slip-twin interactions on multiple fronts while serving as an effective predictive model for CRSS-elevation instrumental in materials design.

To investigate the survival-related factors of patients with advanced stage ovarian cancer who underwent debulking surgery after neoadjuvant chemotherapy (NAC).Two hundred three patients with stage IIIC to IV ovarian cancer who underwent debulking surgery after NAC between 2002 and 2012 were retrospectively analyzed. Overall survival-associated factors, including the performance of optimal surgery, the timing of NAC cycles, the presence of tumour regression according to the pathology report, and lymphadenectomy, were explored using logistic regression analyses.Of the 203 patients, 82% (n = 165) underwent optimal surgery. The median follow-up time was 34 months (range 1-124), and the median overall survival was 37.5 months (95% CI 32.6-42.3). The 5-year overall survival rate was 31.3%. Performance of optimal surgery;4 NAC cycles; presence of tumour regression (either macroscopically, microscopically, or no tumour present) in the omentum according to the pathology report; and lymphadenectomy were found to be statistically significant based on a univariate Cox analysis. Of these factors,1 cm residual tumour, no tumour regression in the omentum according to the pathology report, and4 NAC cycles were significant predictors of a poor prognosis based on a multivariate Cox model (hazard ratio [HR] 1.62, 95% CI 1.02-2.59; HR 2.07, 95% CI 1.36-3.17; HR 1.55, 95% CI 1.07-2.34, respectively).Results of the study support that1 cm residual tumour at the end of the surgery, the presence of a macroscopic tumour in the omentum, and4 NAC cycles were independent poor prognostic factors in patients with advanced stage ovarian, tubal, or peritoneal cancer who underwent surgery after NAC.