As a part of a world-wide study, a commercial code (General Optimization Analyzer), based on multi-scale (micro–macro) progressive failure analysis (PFA), is used to provide theoretical predictions for damage development for a set of challenging 13 test cases proposed in the Third World-Wide Failure Exercise (WWFE-III). Multiple failure criteria were utilized aimed at tackling issues related to a wide range of damage modes, being addressed by the WWFE-III. The critical damage events/indexes predictions tracked translaminar and interlaminar composite failures, namely matrix cracking/crack density, damage initiation/propagation, delamination initiation/growth, and their interaction with fiber failure. The composite laminates analysed were both with and without a central hole and the predictions were made using constituent fiber properties and matrix properties based on materials data or identification from ply stress–strain curve inputs. Loadings included uniaxial tension or compression, biaxial, bending, thermal, and loading–unloading.

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Although tissue stem cells are essential for the maintenance, renewal, and repair of vertebrate organs and tissues, previously, the simple act of counting them has not been possible. For more than a half-century, progress in tissue stem cell research and medicine has been undermined by the lack of a means to determine tissue stem cell number. In particular, a major unmet need for stem cell transplantation medicine has been a way to quantify the specific dosage of tissue stem cell treatments. The counting problem persists because no biomarkers are known that identify tissue stem cells specifically, without also counting their more abundant committed progenitor progeny cells. Here, we describe integration of principles of tissue stem cell asymmetric self-renewal kinetics with computational simulation to achieve specific and accurate counting of therapeutic tissue

A displacement-based variational model is developed to study the effects of transverse cracking and local delaminations in symmetric composite laminates. In the model, the crack shape is assumed to be a function of crack density and delamination length. Using a variational approach with the principle of minimum potential energy, governing equations are derived. The effective Young's modulus E x and energy release rate G are theoretically examined as a result of local delaminations.

The influence of hygrothermal environmental conditions on the load carrying ability and response of composite structures