A physical strategy for the preparation of isotactic polypropylene spheres with microsphere and bead–string spherulite morphologies

This study mainly focuses on the formation of isotactic polypropylene (iPP) blend morphologies with microspheres and distinct bead–string spherulites. iPP microspheres have been prepared by a simple and convenient strategy through either an isothermal or a nonisothermal crystallization process based on the macrophase‐separated structure in molten state of iPP/olefin block copolymer (OBC) blend. The dimension of the iPP spheres can be adjusted easily from about 1 µm to >10 µm by controlling the compatibility and annealing conditions. It was found that any of the following three parameters, the molecular structure of OBC (particularly the octene content), molecular weight of iPP, and annealing condition can be rescaled with others in controlling the dimension of the iPP microspheres. The mechanism of the formation of iPP microspheres was studied in detail. Surprisingly, the typical spinodal decomposition morphology with interconnected or thin sheet structure is the precursor of these microspheres. During the subsequent annealing process, it breaks up and further coarsens into spherical structure. In addition, distinct spherulites with a bead–string substructure have been obtained during the isothermal crystallization. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40863.     

Iron,Neuroinflammation and Neurodegeneration

Disturbance of the brain homeostasis, either directly via the formation of abnormal proteins or cerebral hypo-perfusion, or indirectly via peripheral inflammation, will activate microglia to synthesise a variety of pro-inflammatory agents which may lead to inflammation and cell death. The pro-inflammatory cytokines will induce changes in the iron proteins responsible for maintaining iron homeostasis, such that increased amounts of iron will be deposited in cells in the brain. The generation of reactive oxygen and nitrogen species, which is directly involved in the inflammatory process, can significantly affect iron metabolism via their interaction with iron-regulatory proteins (IRPs). This underlies the importance of ensuring that iron is maintained in a form that can be kept under control; hence, the elegant mechanisms which have become increasingly well understood for regulating iron homeostasis. Therapeutic approaches to minimise the toxicity of iron include N-acetyl cysteine, non-steroidal anti-inflammatory compounds and iron chelation.     

ANSIM: an anesthesia simulator for the IBM PC

Simulations based on physiologic modeling have been used for over twenty years to clarify the pharmacokinetics of inhaled anesthetics. We describe ANSIM, an anesthesia simulator for the IBM PC. ANSIM uses established modeling techniques to create a life-like anesthesia simulator. ANSIM is useful as an educational tool for demonstrating classic concepts of uptake and distribution of inhaled anesthetics.     

My personal history in the early explorations of computer graphics

Gary Demos discovered computer graphics while hearing a computer-generated film presentation at CalTech in 1970 by John Whitney Sr. Gary then began working under the direction of Ivan Sutherland in Utah to develop early computer graphics hardware and software. In 1974 Gary and John Whitney Jr. started the “Motion Picture Project” at Information International to produce computer generated simulated scenes for movies (Futureworld, Looker, and Tron) and commercials. These early computer-generated visuals were quite challenging given the level of software and hardware technology available in the 1970’s. In 1981 Gary and John left Information International to form Digital Productions, where they produced effects for the movies Last Starfighter and “2010”, which were both released in 1984. Digital Productions used the Cray XMP computer, together with the Digital Film Printer that they had developed at Information International. Following a hostile takeover by Omibus of Digital Productions in 1986, Whitney/Demos Productions was formed, using a Thinking Machine parallel computer. This paper describes the technical challenges and achievements of this early visual computing.     

Genetic subsets regression

Subset regression procedures have been shown to provide better overall performance than stepwise regression procedures. However, due to the combinatorial nature of evaluating each potential subset, subset regression techniques are costly to use. To resolve this difficulty, the use of a simple genetic algorithm (GA) is proposed to reduce the number of subsets which must be evaluated. Any of a number of popular criteria, including Mallows' C_p, MSE, R², AIC, etc., can be used to drive the search strategy associated with the use of the GA. Several illustrated examples on its use are provided.