Statistical thermodynamic basis in drug-receptor interactions: double annihilation and double decoupling alchemical theories, revisited

Alchemical theory is emerging as a promising tool in the context of molecular dynamics simulations for drug discovery projects. In this theoretical contribution, I revisit the statistical mechanics foundation of non covalent interactions in drug-receptor systems, providing a unifying treatment that encompasses the most important variants in the alchemical approaches, from the seminal Double Annihilation Method by Jorgensen and Ravimohan [W.L. Jorgensen and C. Ravimohan, J. Chem. Phys. 83,3050, 1985], to the Gilson's Double Decoupling Method [M. K. Gilson and J. A. Given and B. L. Bush and J. A. McCammon, Biophys. J. 72, 1047 1997] and the Deng and Roux alchemical theory [Y. Deng and B. Roux, J. Chem. Theory Comput., 2, 1255 2006]. Connections and differences between the various alchemical approaches are highlighted and discussed, and finally placed into the broader context of nonequilibrium thermodynamics.Comment: 25 pages, 4 figure

Right Brain Review- Winter 1990

Contributors include: Richard Kolko, David Cooper, D.E. Marshall, Lesley J. Litwin, Anita Ruterschmidt, Eileen Sandman, Marilyn C. Mueller, Kate Walztoni, Dan Melzer, Hannah Alexander, Joe Bandford, Marsha Caddell, Lillie D. Chaffin, Rita Cerisi, Robert Cooperman, Jameson Currier, William Gilson, Carol L. Gloor, Mary Barbara Hess, A.C. Kaiser, Robert S. King, Mindy Kronenberg, Barbara F. Lefcowitz, Duane Locke, Beverly G. Merrick, Sheryl L. Nelms, Portia, Andrea Potos, Gertrude Rubin, Brian Skinner, Laurel Speer, Peter Spiro, Anne Valdez, Barbara Van Noordhttps://neiudc.neiu.edu/rightbrain/1000/thumbnail.jp

Note on the physical basis of spatially resolved thermodynamic functions

The spatial resolution of thermodynamic functions, exemplified by the entropy, is discussed. A physical definition of the spatial resolution based on a spatial analogy of the partial molar entropy is advocated. It is shown that neither the grid cell theory (Gerogiokas et al., J. Chem. Theory Comput., 10, 35 [2014]), nor the first-order grid inhomogeneous solvation theory (Nguyen et al. J. Chem. Phys., 137, 044101 [2012]), of spatially resolved hydration entropies satisfies the definition.Comment: Essentially 2 double-column pages, no figure

Simple estimation of absolute free energies for biomolecules

One reason that free energy difference calculations are notoriously difficult in molecular systems is due to insufficient conformational overlap, or similarity, between the two states or systems of interest. The degree of overlap is irrelevant, however, if the absolute free energy of each state can be computed. We present a method for calculating the absolute free energy that employs a simple construction of an exactly computable reference system which possesses high overlap with the state of interest. The approach requires only a physical ensemble of conformations generated via simulation, and an auxiliary calculation of approximately equal central-processing-unit (CPU) cost. Moreover, the calculations can converge to the correct free energy value even when the physical ensemble is incomplete or improperly distributed. As a "proof of principle," we use the approach to correctly predict free energies for test systems where the absolute values can be calculated exactly, and also to predict the conformational equilibrium for leucine dipeptide in implicit solvent.Comment: To appear in J. Chem. Phys., 10 pages, 6 figure

Irradiation of Materials with Short, Intense Ion pulses at NDCX-II

We present an overview of the performance of the Neutralized Drift Compression Experiment-II (NDCX-II) accelerator at Berkeley Lab, and report on recent target experiments on beam driven melting and transmission ion energy loss measurements with nanosecond and millimeter-scale ion beam pulses and thin tin foils. Bunches with around 10^11 ions, 1-mm radius, and 2-30 ns FWHM duration have been created with corresponding fluences in the range of 0.1 to 0.7 J/cm^2. To achieve these short pulse durations and mm-scale focal spot radii, the 1.1 MeV He+ ion beam is neutralized in a drift compression section, which removes the space charge defocusing effect during final compression and focusing. The beam space charge and drift compression techniques resemble necessary beam conditions and manipulations in heavy ion inertial fusion accelerators. Quantitative comparison of detailed particle-in-cell simulations with the experiment play an important role in optimizing accelerator performance.Comment: 15 pages, 7 figures. revised manuscript submitted to Laser and Particle Beam

Argo data 1999-2019: two million temperature-salinity profiles and subsurface velocity observations from a global array of profiling floats.

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wong, A. P. S., Wijffels, S. E., Riser, S. C., Pouliquen, S., Hosoda, S., Roemmich, D., Gilson, J., Johnson, G. C., Martini, K., Murphy, D. J., Scanderbeg, M., Bhaskar, T. V. S. U., Buck, J. J. H., Merceur, F., Carval, T., Maze, G., Cabanes, C., Andre, X., Poffa, N., Yashayaev, I., Barker, P. M., Guinehut, S., Belbeoch, M., Ignaszewski, M., Baringer, M. O., Schmid, C., Lyman, J. M., McTaggart, K. E., Purkey, S. G., Zilberman, N., Alkire, M. B., Swift, D., Owens, W. B., Jayne, S. R., Hersh, C., Robbins, P., West-Mack, D., Bahr, F., Yoshida, S., Sutton, P. J. H., Cancouet, R., Coatanoan, C., Dobbler, D., Juan, A. G., Gourrion, J., Kolodziejczyk, N., Bernard, V., Bourles, B., Claustre, H., D'Ortenzio, F., Le Reste, S., Le Traon, P., Rannou, J., Saout-Grit, C., Speich, S., Thierry, V., Verbrugge, N., Angel-Benavides, I. M., Klein, B., Notarstefano, G., Poulain, P., Velez-Belchi, P., Suga, T., Ando, K., Iwasaska, N., Kobayashi, T., Masuda, S., Oka, E., Sato, K., Nakamura, T., Sato, K., Takatsuki, Y., Yoshida, T., Cowley, R., Lovell, J. L., Oke, P. R., van Wijk, E. M., Carse, F., Donnelly, M., Gould, W. J., Gowers, K., King, B. A., Loch, S. G., Mowat, M., Turton, J., Rama Rao, E. P., Ravichandran, M., Freeland, H. J., Gaboury, I., Gilbert, D., Greenan, B. J. W., Ouellet, M., Ross, T., Tran, A., Dong, M., Liu, Z., Xu, J., Kang, K., Jo, H., Kim, S., & Park, H. Argo data 1999-2019: two million temperature-salinity profiles and subsurface velocity observations from a global array of profiling floats. Frontiers in Marine Science, 7, (2020): 700, doi:10.3389/fmars.2020.00700.In the past two decades, the Argo Program has collected, processed, and distributed over two million vertical profiles of temperature and salinity from the upper two kilometers of the global ocean. A similar number of subsurface velocity observations near 1,000 dbar have also been collected. This paper recounts the history of the global Argo Program, from its aspiration arising out of the World Ocean Circulation Experiment, to the development and implementation of its instrumentation and telecommunication systems, and the various technical problems encountered. We describe the Argo data system and its quality control procedures, and the gradual changes in the vertical resolution and spatial coverage of Argo data from 1999 to 2019. The accuracies of the float data have been assessed by comparison with high-quality shipboard measurements, and are concluded to be 0.002°C for temperature, 2.4 dbar for pressure, and 0.01 PSS-78 for salinity, after delayed-mode adjustments. Finally, the challenges faced by the vision of an expanding Argo Program beyond 2020 are discussed.AW, SR, and other scientists at the University of Washington (UW) were supported by the US Argo Program through the NOAA Grant NA15OAR4320063 to the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) at the UW. SW and other scientists at the Woods Hole Oceanographic Institution (WHOI) were supported by the US Argo Program through the NOAA Grant NA19OAR4320074 (CINAR/WHOI Argo). The Scripps Institution of Oceanography's role in Argo was supported by the US Argo Program through the NOAA Grant NA15OAR4320071 (CIMEC). Euro-Argo scientists were supported by the Monitoring the Oceans and Climate Change with Argo (MOCCA) project, under the Grant Agreement EASME/EMFF/2015/1.2.1.1/SI2.709624 for the European Commission

M. F. Sciaccas’s Ontology and Philosophical Tradition

Michele Federico Sciacca (1908—1975) is little-known outside the Roman world. Meanwhile, he is the author of a comprehensive metaphysical system of a Platonic-Augustinian-Rosminian and, at the later stage, also of a Thomist, orientation. The reason for a seemingly insufficient interest to Sciacca’s philosophy in Italy may be that he has elaborated no particular histo- rico-philosophical methodology. Even his metaphysics, despite the renaissance of the metaphysical tendency among Italian philosophers, enjoys rather small popularity and is outweighted by the Padua school oriented towards the classical Aristotelean metaphysics and influenced by the Tubingen school (in the first place, by H.-J. Kramer )