BACKGROUND Human solid tumors that are hard or firm on physical palpation are likely to be cancerous, a clinical maxim that has been successfully applied to cancer screening programs, such as breast self-examination. However, the biological relevance or prognostic significance of tumor hardness remains poorly understood. Here we present a fracture mechanics based in vivo approach for characteri...

AIM We conducted two studies that examined different models, which included mental toughness and psychological constructs that have been found to be related to this construct. METHODS In Study 1, 531 athletes completed measures of mental toughness, resilience, and emotional intelligence. In Study 2, 522 athletes completed measures of mental toughness, sport motivation, and self-efficacy. RE...

Two sets of WC-Co grades were produced, with cobalt content ranging from 3 to 50 wt.%. The mean grain size of the two sets was 2.2 and 6 ~tm respectively. The two sets of grades were used to investigate the relationship between hardness and fracture toughness. It was found that at constant WC grain size the relationship is linear. It was also found that in the low toughness range, grades of equ...

BACKGROUND/AIM Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of...

RICE et ml. (1994, J. Mech. Ph_vs. Solids 42, 813-843) analyse the propagation of a planar crack with a nominally straight front in a model elastic solid with a single displacement component. Using the form of their results for a strictly linearized perturbation from a straight crack front which moves at uniform speed, we give the corresponding first-order expression for the deviation of a crac...

Bainitic transformation at low transformation temperatures leads to a microstructure involving fine plates of bainitic ferrite and thin films of retained austenite. This microstructure has shown ultimate tensile strength of about 2.2 GPa, noticeable uniform elongation in the range of 5 to 30%, hardness values of about 600 to 670 HV and impact toughness in the range of 30 to 40 MPa m1/2. With ca...