After criticism, more modest cancer genome project takes shape
An expensive federal project to identify the genetic changes that cause cancer is blazing ahead despite loud skepticism from some scientists. The US National Institutes of Health (NIH) is set to begin taking applications for the project in early March.
Establishing a culture of care, conscience, and responsibility: addressing the improvement of scientific discovery and animal welfare through science-based performance standards.
Science-based performance standards offer a viable means of reducing regulatory burden while ensuring that research animal welfare and high-quality research data are realized. Unlike rigid regulations, science-based performance standards evolve as new information becomes available, thereby allowing new discoveries to be implemented in a timely manner and in a way that more effectively benefits the animals and the science. The implementation of performance standards requires a well-coordinated institutional team composed of the administration, research staff, the institutional animal care and use committee, professional and technical animal care personnel, occupational health and safety staff, and physical plant staff. This animal program team is best supported in an institutional environment that reflects a culture of care, compliance, and responsibility. In such a culture, the professional judgment exercised by the team is well grounded in meeting the diverse needs of the program's customers, who include the animals, the researchers, and research stakeholders such as the public. The institutional culture of care, compliance, and responsibility fosters workplace integrity, an ethics-based decision-making paradigm, sound understanding of institutional expectations through good communication and clear lines of authority, the hiring and retention of trained and well-qualified individuals, and a system for continuous development and improvement of the program.
Damage initiation and propagation in composite shells subjected to impact
Abstract The paper investigates the impact-induced damage initiation and propagation for laminated composite shells under low-velocity impact. A three-dimensional eight-node non-conforming element is described to analyze interlaminar stress distribution, and progressive failure. The damage analysis is performed by using Tsai–Wu quadratic failure criterion, Tsai’s damage modes and an additional delamination formula at all Gaussian points. The damage modes considered are matrix cracking, fiber breakage and delamination. The progressive failure is expressed by reducing stiffness of the material at all failed Gaussian points. Special attention is centered on curved laminates. Impact energy threshold for the onset of damage and transient damage size are predicted for composite shells. The analyses of the flat and curved laminates are compared for discussing their different damage mechanism. In addition, the influence of the stacking sequence, the thickness and the radius of curvature on damage behavior of composite shells are studied.