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A systematic characterization of the motion and friction of a linear bearing with rolling elements used for nanopositioning reveals an explicit distinction of static and rolling friction. The effects

For the polymer-supported metal thin films that are finding increasing applications, the critical strain to nucleate microcracks ( εc ) should be more meaningful than the generally measured rupture strain. In this paper, we develop both electrical resistance method and microcrack analyzing method to determine εc of polymer-supported Cu films simply but precisely. Significant thickness dependence has been clearly revealed for εc of the polymer-supported Cu films, i.e., thinner is the film lower is εc . This dependence is suggested to cause by the constraint effect of refining grain size on the dislocation movability.

I’m delighted that mechanicians now have this platform to discuss our work as well as share ideas and perspectives. While we advance knowledge in our field and come up with innovative solutions for engineering and materials problems, I believe that we also have a responsibility to speak on issues of global significance, especially where the power of science and technology can be harnessed to address challenges and issues impacting the world.

Rubber or rubber-like materials, or generally elastomers, sustain large elastic deformations. The problems of such cases are non-linear, the non-linearity came from two sources, the first one due to materials, and the second is geomertrical non-linearity. Elastomers are, also, viscoelastic, i.e. time and temperature dependent.

Recently I received a message from the Cambridge University Press regarding a coming text on biomechanics entitled Introductory Biomechanics, From Cells to Organisms. by C. Ross Ethier and Craig A. Simmonds. I ordered an exam copy, went through, and found it very interesting. It covers cellular biomechanics, hemodynamics, circulatory system, ocular biomechanics, muscles and movement, and skeletal biomechanics. Each section has a significant number of problems. I examined closely the part on cellular biomechanics which is one of the main areas of my research and teaching interests, and enjoyed reading it. The cellular mechanics is presented in its interrelation to cell structure and biology (there are nice images of cells and their components to use for teaching). The main techniques of probing the cell, such as micropipette aspiration, AFM, optical tweezers, and magnetic cytometry, are considered. Models of the cytoskeleton (tensergity, foams) are also introduced. The math is limited to linear equations, one-dimensional or axisymmetric problems, but it seems appropriate for the introductory level. In addition, some results of computational (finite element) modeling are also included. I certainly expect that this textbook will be quite useful in my teaching. The web site http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=9780521841122 has more details on the book.