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Short colloidal chains are simulated by the slithering-snake-algorithm on a simple cubic lattice. The dipole character of the colloidal particles leads to a long range dipole–dipole interaction. The solvent is simulated by the nearest neighbor Ising model. The aligning of the dipoles under a magnetic field gives rise to the chains to align on their part with the field direction.

A 12 T twin-aperture subscale magnet is under development at the Institute of High Energy Physics (IHEP, Beijing, China), as the R&D of high-field accelerator magnet technology for SPPC (Super Proton–Proton Collider) pre-study. Four NbTi coils and two Nb₃Sn coils will be fabricated firstly, to provide a 12 T dipole field in two apertures with the load line ratio of 20% at 4.2 K. After that, the HTS (ReBCO and Bi-2212) coils will be inserted between the Nb₃Sn coils to realize a higher dipole field. The ReBCO coils with the block-type configuration will be inserted between the Nb₃Sn coils with common-coil configuration (Combined Common-coil and Block type configuration, CCB), to make the broad plane of the tape parallel with the magnetic flux and maximize current-carrying capacity. The electromagnetic design, mechanical design and quench protection design have been completed. The fabrication is ongoing. The magnet will be assembled and tested in 2017.

The tubulin dimers of microtubules are arranged in a crystalline lattice which is wrapped to form a long cylinder. Two different arrangements of monomers within the lattice have been postulated: the A-lattice and the B-lattice. Previous studies have assumed that both lattice types are hexagonal with each dimer surrounded by six nearest-neighbors. Based on recent biochemical studies I argue that both lattice types can also be formed with each dimer having four nearest-neighbors. This has important consequences for the overall behavior of the model. It is generally assumed that tubulin dimers possess a mobile electric dipole which can exist in one of two discrete Ising spin states: -1 (down) or +1 (up). The average of all these states within a microtubule is the mean polarization and is a measure of the dipole ordering within the lattice. Microtubule models with six nearest-neighbors behave like models of ferroelectric substances: at low temperatures the lattice is highly ordered with most (if not all) dipoles pointing in the same direction, but as the temperature increases, the degree of ordering decreases due to random thermal flipping of the dipoles. The mean polarization is particularly erratic at physiological temperatures. In contrast, when the microtubule lattice is modeled with four nearest-neighbors, the mean lattice polarization is quite stable and remains close to zero over a wide temperature range that includes 37°C (310K). This raises new questions about the biophysical role of microtubules.

A multi-dimensional wavelet neural network is proposed to localize current dipole within the brain based on a head volume conductor model of realistic shape. Training patterns containing 127 scalp potential elements in response to current dipoles are calculated by using the boundary element method. We utilize scalp potentials and dipole parameters, respectively, as the inputs and outputs to the net. A total of 8,000 pairs of input and output vectors are generated by the boundary element method to train the net. After training, 2,000 independent pairs of test vectors are utilized to evaluate dipole localization results. Our data indicate that the wavelet neural network is able to perform dipole localization both efficiently and accurately.