Rotators structural-dynamical model

Halle and Davidovic developed a dynamic model that explicitly links protein hydrodynamics to hydration dynamics. With the aid of this model structure-based predictions of global biomolecular dynamics become possible. The validity of the model was demonstrated for a set of proteins for which accurate experimental rotational diffusion coefficients are available. Boisbouvier et al derived the rotational diffusion tensor of nucleic acid from relaxation times. 

The rotational isomeric state model is a well established technique for deriving the static properties of polymers from the chemical structure. The dynamic rotational isomeric state approach is its dynamic counterpart. It is the first step for gaining insights as to the role of the intrinsic chemical structure on observed properties. It may be applied to the prediction trf the intrinsic dynamics of polymers, i.e., those occurring in the absence of external effects, and to the examination of the relative relaxation rates of different units along a givoi chain. This will pertain to both homopolymers composed of different types rrf backbone atoms, and to copolymers built of different monomeric units. 

The results presented in this chapter show that the use of proper effective models, in combination with calculations based on the exact vibrational Hamiltonian, constitutes a promising approach to study the laser driven vibrational dynamics of polyatomic molecules. In this context, the MCTDH method is an invaluable tool as it allows to compute the laser driven dynamics of polyatomic molecules with a high accuracy. However, our models still contain simplifications that prevent a direct comparison of our results with potential experiments. First, the rotational motion of the molecule was not explicitly described in the present work. The inclusion of the rotation in the description of the dynamics of the molecule is expected to be important in several ways. First, even at low energies, the inclusion of the rotational structure would result in a more complicated system with different selection rules. In addition, the orientation of the molecule with respect to the laser field polarization would make the control less efficient because of the rotational averaging of the laser-molecule interaction and the possible existence of competing processes. On the other hand, the combination of the laser control of the molecular alignment/orientation with the vibrational control proposed in this work could allow for a more complete control of the dynamics of the molecule. A second simplification of our models concerns the initial state chosen for the simulations. We have considered a molecule in a localized coherent superposition of vibrational eigenstates but we have not studied the preparation of this state. We note here that a control scheme for the localiza-... 

This study total reviewed 130 patients treated hy dynamic hip screw surgery and classified the fracture according to AO system. Statistic data showed that the common unstable femoral proximal fracture type is A2.1 (AO classification). The osteoporotic femur model of finite element method (FEM) was developed from the CT image of 80 years patient. Loading condition assigned single-leg stance. The FEM analytic result show the lesser trochanter has a moment of rotation in dynamic fixation without wires fixation condition. Using wires to fix the lesser trochanter can enhance the structure stiffness and reduce the stress distribution in unstable intertrochanter fracture (A2.1 type). 

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