BACKGROUND Psychological stress is an important factor of acne pathogenesis. Stress related production of hormones, cytokines and neuropeptides may result in the chronic course and exacerbations of the disease. OBJECTIVE The aim of the study was to evaluate the relationship between acne severity, intensity of emotional stress and serum concentration of substance P (scSP), to compare the inten...

In the setting of antiplane linearized elasticity, we show the existence of the stress intensity factor and its relation with the energy release rate when the crack path is a C curve. Finally, we show that the energy release rate is continuous with respect to the Hausdorff convergence in a class of admissible cracks.