This article offers an overview of the molecular simulation studies of adsorption on solid surfaces. First of all, various models of adsorbents used in different chromatographic modes are reviewed, including coarse-grained models and all-atom models, depending on the description precision required and the computational

power provided. In the adsorbent models, the surface morphology is visualized using Monte Carlo simulation or molecular dynamics simulation. Then, studies on the adsorption and retention behaviors of small molecules by these models and methods are summarized. Finally, emphases are focused on the check details application of molecular simulation to protein adsorption, including protein-surface interaction, protein orientation and conformational transition on solid surfaces. In these studies, the effects of ligand parameters, including the ligand composition, ligand length, bonding density, ligand distribution have been examined. Meanwhile, chromatographic parameters, including the mobile phase composition and temperature, have also been investigated. Based on the

successful applications reviewed herein, it is concluded that molecular simulation studies have contributed to the development of adsorption and chromatography in bioseparations. Moreover, it is suggested that molecular simulation combined with computational quantum chemistry and experiments would provide more comprehensive understanding of adsorption phenomena learn more in the future. (C) 2009 Elsevier B.V. All rights reserved.”
“Cannulation of the abdominal aorta in older donors with advanced atherosclerotic disease is challenging and may lead to dissection or plaque embolization. We describe a different technique, short segment aortic endarterectomy, which can be a useful alternative during organ procurement. It permits safer cannulation and securing of atherosclerotic infrarenal aortas, thereby allowing us to flush and safely use organs that otherwise would have been discarded.”
“We see more report on systematic study of photoluminescence

properties of nanocrystalline titanium dioxide films consisting of predominantly anatase nanoparticles with diameters larger than 13 nm. We measured photoluminescence under two selected excitation wavelengths (325 nm/442 nm, i.e., above/below band gap excitation), under different values of ambient air pressure (5-10(5) Pa), and in the temperature interval 10-300 K. On basis of our results, we are able to distinguish two different processes leading to photoluminescence: the exciton recombination and the recombination of carriers in the energy states related to the surface of nanocrystals. We propose microscopic models describing well the effects of temperature and ambient conditions on photoluminescence of nanocrystalline titanium dioxide films. (C) 2010 American Institute of Physics. [doi:10.1063/1.