Phono-spectrographic analysis of heart murmur in children

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Treatment of critical neonatal edema with hemo-ultrafiltration

Three neonates with extreme edema associated with cardiovascular and renal insufficiency were treated with hemo-ultrafiltration for removal of critical edema fluid. In each patient peritoneal dialysis had not been effective in expedient fluid removal. Ultrafiltration was accomplished by occlusion of the proximal dialysate portal of a Travenol EX12-11, 0.8 m2 dialyzer and the application of vacuum suction to the distal portal. Blood flow ranged from 10-25 ml/min. The rate of ultrafiltration averaged 0.57 ml/kg/min resulting in losses of 4-16% of body weight. Episodes of hypotension were associated with too rapid ultrafiltration rate and not total volume removed. All patients tolerated the procedure. Two of the three patients demonstrated improvement in blood pressure, oxygenation and urine flow following the ultrafiltration. Ultrafiltration in the newborn may be a useful therapeutic procedure when conventional treatment fails

Soft x-ray emission studies of several aluminum alloys

During the first few months of operation of our soft x-ray spectrometer at the NSLS, we have measured the L emission spectrum for three classes of aluminum alloys: dilute aluminum-magnesium alloys to extend the Al-Mg system to the impurity limit; a 50-50 alloy of aluminum-lithium to characterize the band structure of bulk samples of this potential battery electrolite; and the icosahedral and normal Al-Mn alloys to see if the two phases had measurably different density of states which have been predicted. All spectra shown are produced when core holes generated by energetic electrons or photons are filled by radiative transitions from conduction band states. Dipole selection rules govern the transitions. Thus, K spectra provide a measure of the p-symmetic partial density of states (DOS) near the atom. Similarly, L spectra produced by transitions to p-core holes map the s and d symmetric DOS in the vicinity of the atom with the core hole

Enhancing Biomolecular Simulations with Hybrid Potentials Incorporating NMR Data.

Some recent advances in biomolecular simulation and global optimization have used hybrid restraint potentials, where harmonic restraints that penalize conformations inconsistent with experimental data are combined with molecular mechanics force fields. These hybrid potentials can be used to improve the performance of molecular dynamics, structure prediction, energy landscape sampling, and other computational methods that rely on the accuracy of the underlying force field. Here, we develop a hybrid restraint potential based on NapShift, an artificial neural network trained to predict protein nuclear magnetic resonance (NMR) chemical shifts from sequence and structure. In addition to providing accurate predictions of experimental chemical shifts, NapShift is fully differentiable with respect to atomic coordinates, which allows us to use it for structural refinement. By employing NapShift to predict chemical shifts from the protein conformation at each simulation step, we can compute an energy penalty and the corresponding hybrid restraint forces based on the difference between the predicted values and the experimental chemical shifts. The performance of the hybrid restraint potential was benchmarked using both basin-hopping global optimization and molecular dynamics simulations. In each case, the NapShift hybrid potential improved the accuracy, leading to better structure prediction via basin-hopping and increased local stability in molecular dynamics simulations. Our results suggest that neural network hybrid potentials based on NMR observables can enhance a broad range of molecular simulation methods, and the prediction accuracy will improve as more experimental training data become available