The complex Kohn variational method applied to N-d scattering

The three-nucleon ground state and the N--d scattering states are obtained using variational principles. The wave function of the system is decomposed into angular-spin-isospin channels and the corresponding two dimensional spatial amplitudes are expanded in a correlated polynomial basis. For the scattering states, the complex form of the Kohn variational principle is used to determine the $S$--matrix. Special attention is given to the convergence pattern of the phase-shift and mixing parameters. The calculations have been performed using realistic local NN potentials and three-nucleon forces. Important features of the method are anomaly-free solutions and the low dimensionality of the matrices involved allowing for the inclusion of a large number of states. Very precise and stable numerical results have been obtained.Comment: Latex, 22 pages; 5 figure

Sexually Transmitted Diseases (STDs)

High rates of unprotected sexual behavior in adolescents result in millions of cases of STDs in the world. This chapter reviews factors inducing high STD rates, specific STDs, and their management based on 2010 U.S. Centers for Disease Control and Prevention (CDC) STD guidelines. Clinicians should screen all their sexually active adolescent patients for STDs and provide preventive education as well as treatment measures

Multistage asthenospheric melt/rock reaction in the ultraslow eastern SWIR mantle

Very small amounts of melt are produced during mantle upwelling beneath the ultraslow spreading South West Indian Ridge. Sectors of this Oceanic Ridge are characterized by nearly amagmatic spreading with rare limited eruptions of basalts spotting a mantle-derived serpentinitic crust. A large peridotite dataset was recovered during the Smoothseafloor French expedition leaded by D. Sauter and M. Cannat in 2005 (Sauter et al., 2013). Mantle-derived rocks show a significant modal variability from the sample to the dredge scale with frequent occurrences of millimetric to centimetric spinel-bearing pyroxenitic veins. Mantle residua record a multistage reactional history between small amount of transient melts and variably depleted mantle parcels. Incomplete mineral replacements are widespread showing that both pyroxenes are repeatedly dissolved and recrystallized leaving poekilitic pyroxene and spinel textures. Reacting conditions are modelled assuming an incremental open-system melting model under variable critical porosity/F ratios (Seyler et al., 2011; Brunelli et al., 2014). Incoming melts result to be generated by low degrees of melting in the garnet field then reacting with the rock under near-batch conditions, i.e. at low rates of melt extraction with respect to the actual rock porosity. As a consequence Na (and LREE) countertrends with melting indicators as mineral Cr# and concentration of the moderately incompatible elements (HREE, HFSE). This results in rotation of the REE patterns around a pivot element instead of showing progressive depletion as expected after suboceanic mantle decompression. Brunelli D., Paganelli E. & Seyler, M. 2014. Percolation of enriched melts during incremental open-system melting in the spinel field: A REE approach to abyssal peridotites from the Southwest Indian Ridge. Geoch. et Cosmoch. Acta, 127, 190–203. doi:10.1016/j.gca.2013.11.040. Sauter D., Cannat M., Searle R. 2013. Continuous exhumation of mantle-derived rocks at the Southwest Indian Ridge for 11 million years. Nature Geosci., 6(4), 1–7. doi:10.1038/ngeo1771. Seyler M., Brunelli D., Toplis M. J. & Mével C. (2011). Multiscale chemical heterogeneities beneath the eastern Southwest Indian Ridge (52°E-68°E): Trace element compositions of along-axis dredged peridotites. Geochem. Geophys. Geosyst., 12, Q0AC15. doi:10.1029/2011gc003585

Sexually Transmitted Diseases in Adolescence

High rates of unprotected sexual behavior in adolescents result in millions of sexually transmitted diseases (STDs) in the world. This paper reviews factors inducing high STD rates, specific STDs, and their management based on 2010 US Centers for Disease and Prevention (CDC) STD guidelines. Clinicians should screen all their sexually active adolescent patients for STDs and provide preventive education as well as treatment measures

Time-series transcriptomics from cold, oxic subseafloor crustal fluids reveals a motile, mixotrophic microbial community

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Seyler, L. M., Trembath-Reichert, E., Tully, B. J., & Huber, J. A. Time-series transcriptomics from cold, oxic subseafloor crustal fluids reveals a motile, mixotrophic microbial community. Isme Journal, (2020), doi:10.1038/s41396-020-00843-4.The oceanic crustal aquifer is one of the largest habitable volumes on Earth, and it harbors a reservoir of microbial life that influences global-scale biogeochemical cycles. Here, we use time series metagenomic and metatranscriptomic data from a low-temperature, ridge flank environment representative of the majority of global hydrothermal fluid circulation in the ocean to reconstruct microbial metabolic potential, transcript abundance, and community dynamics. We also present metagenome-assembled genomes from recently collected fluids that are furthest removed from drilling disturbances. Our results suggest that the microbial community in the North Pond aquifer plays an important role in the oxidation of organic carbon within the crust. This community is motile and metabolically flexible, with the ability to use both autotrophic and organotrophic pathways, as well as function under low oxygen conditions by using alternative electron acceptors such as nitrate and thiosulfate. Anaerobic processes are most abundant in subseafloor horizons deepest in the aquifer, furthest from connectivity with the deep ocean, and there was little overlap in the active microbial populations between sampling horizons. This work highlights the heterogeneity of microbial life in the subseafloor aquifer and provides new insights into biogeochemical cycling in ocean crust.The Gordon and Betty Moore Foundation sponsored most of the observatory components at North Pond through grant GBMF1609. This work was supported by NSF OCE-1062006, OCE-1745589 and OCE-1635208 to J.A.H. E.T.R. was supported by a NASA Postdoctoral Fellowship with the NASA Astrobiology Institute and a L’Oréal USA For Women in Science Fellowship. The Center for Dark Energy Biosphere Investigations (C-DEBI OCE-0939564) also supported the participation of J.A.H. and B.T. This is C-DEBI contribution number 548

Recent Developments in Few-Nucleon Systems

N-d elastic scattering is studied at different energies using one of the modern NN interactions, the Argonne v_{18} which explicitly includes the magnetic moment interaction between two nucleons. This interaction, which has been often neglected in the description of the few-nucleon continuum, produces sizable modifications in some elastic observables. Its effects, as well as those produced by the Coulomb potential, are analyzed as a function of energy. The magnetic moment interaction produces appreciable effects in $p-d$ scattering at low energies butthey are very small above 10 MeV. Above 65 MeV Coulomb effects can be observed only in specific observables as for example $T_{21}$.Comment: 9 pages, 5 figures, invited talk at the 17th International IUPAP Conference on Few-Body problems in Physics, June 5-10, 2003, Durham (USA