Abundances and Physical Conditions in the Warm Neutral Medium Towards mu Columbae

We present ultraviolet interstellar absorption line measurements for the sightline towards the O9.5 V star mu Columbae obtained with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope. These archival data represent the most complete GHRS interstellar absorption line measurements for any line of sight towards an early-type star. The 3.5 km/s resolution of the instrument allow us to accurately derive the gas-phase column densities of many important ionic species in the diffuse warm neutral medium using a combination of apparent column density and component fitting techniques, and we study in detail the contamination from ionized gas along this sightline. The low-velocity material shows gas-phase abundance patterns similar to the warm cloud (cloud A) towards the disk star zeta Oph, while the component at v = +20.1 km/s shows gas-phase abundances similar to those found in warm halo clouds. We find the velocity-integrated gas-phase abundances of Zn, P, and S relative to H along this sightline are indistinguishable from solar system abundances. We discuss the implications of our gas-phase abundance measurements for the composition of interstellar dust. The relative ionic column density ratios of the intermediate velocity components show the imprint both of elemental incorporation into grains and (photo)ionization. The components at v = -30 and -48 km/s along this sightline likely trace shocked gas with very low hydrogen column densities. Appendices include a new derivation of the GHRS instrumental line spread function, and a new very accurate determination of the total H I column along this sightline. (Abridged)Comment: Accepted for publication in the Astrophysical Journal. 80 pages including 19 embedded figures and 12 embedded tables. Version with higher resolution figures can be downloaded from http://fuse.pha.jhu.edu/~howk/Papers/papers.htm

Angular Momentum and the Formation of Stars and Black Holes

The formation of compact objects like stars and black holes is strongly constrained by the requirement that nearly all of the initial angular momentum of the diffuse material from which they form must be removed or redistributed during the formation process. The mechanisms that may be involved and their implications are discussed for (1) low-mass stars, most of which probably form in binary or multiple systems; (2) massive stars, which typically form in clusters; and (3) supermassive black holes that form in galactic nuclei. It is suggested that in all cases, gravitational interactions with other stars or mass concentrations in a forming system play an important role in redistributing angular momentum and thereby enabling the formation of a compact object. If this is true, the formation of stars and black holes must be a more complex, dynamic, and chaotic process than in standard models. The gravitational interactions that redistribute angular momentum tend to couple the mass of a forming object to the mass of the system, and this may have important implications for mass ratios in binaries, the upper stellar IMF in clusters, and the masses of supermassive black holes in galaxies.Comment: Accepted by Reports on Progress in Physic

The Evolution of the Elemental Abundances in the Gas and Dust Phases of the Galaxy

We present models for the evolution of the elemental abundances in the gas and dust phases of the interstellar medium (ISM) of our Galaxy by generalizing standard models for its dynamical and chemical evolution. In these models, the stellar birthrate history is determined by the infall rate of primordial gas, and by its functional dependence on the mass surface density of the stars and gas. We adopt a two component model for the Galaxy, consisting of a central bulge and an exponential disk with different infall rates and stellar birthrate histories. Condensation in stellar winds, Type Ia and Type II supernovae, and the accretion of refractory elements onto preexisting grains in dense molecular clouds are the dominant contributors to the abundance of elements locked up in the dust. Grain destruction by sputtering and evaporative grain-grain collisions in supernova remnants are the most important mechanisms that return these elements back to the gas phase. We calculate the dust production rate by the various dust sources, analyze the origin of the elemental depletion pattern, and study the relation between dust abundance and ISM metallicity, and the evolution of the the dust abundance and composition at each Galactocentric radius as a function of time. The derived relation of dust mass with metallicity is compared to the observed Galactic dust abundance gradient, and to the M$_{dust}$ versus log(O/H) relation that is observed in external Dwarf galaxies. The dependence of dust composition on the mass of the progenitor star, and the delayed recycling of newly synthesized dust by low mass stars back to the ISM give rise to variations in the dust composition as a function of time. Our models provide a framework for the self-consistent inclusion of dust inComment: AAS TeX manuscript - submitted to ApJ (47 pages) + 15 Figures corrected figure file

The Mass Distribution and Rotation Curve in the Galaxy

The mass distribution in the Galaxy is determined by dynamical and photometric methods. Rotation curves are the major tool for determining the dynamical mass distribution in the Milky Way and spiral galaxies. The photometric (statistical) method utilizes luminosity profiles from optical and infrared observations, and assumes empirical values of the mass-to-luminosity (M/L) ratio to convert the luminosity to mass. In this chapter the dynamical method is described in detail, and rotation curves and mass distribution in the Milky Way and nearby spiral galaxies are presented. The dynamical method is categorized into two methods: the decomposition method and direct method. The former fits the rotation curve by calculated curve assuming several mass components such as a bulge, disk and halo, and adjust the dynamical parameters of each component. Explanations are given of the mass profiles as the de Vaucouleurs law, exponential disk, and dark halo profiles inferred from numerical simulations. Another method is the direct method, with which the mass distribution can be directly calculated from the data of rotation velocities without employing any mass models. Some results from both methods are presented, and the Galactic structure is discussed in terms of the mass. Rotation curves and mass distributions in external galaxies are also discussed, and the fundamental mass structures are shown to be universal.Comment: 54 pages, 25 figures, in 'Planets, Stars and Stellar Systems', Springer, Vol. 5, ed. G. Gilmore, Chap. 19. Note: Preprint with full figures is available from http://www.ioa.s.u-tokyo.ac.jp/~sofue/htdocs/2013psss

Systematic evaluation of immune regulation and modulation

Cancer immunotherapies are showing promising clinical results in a variety of malignancies. Monitoring the immune as well as the tumor response following these therapies has led to significant advancements in the field. Moreover, the identification and assessment of both predictive and prognostic biomarkers has become a key component to advancing these therapies. Thus, it is critical to develop systematic approaches to monitor the immune response and to interpret the data obtained from these assays. In order to address these issues and make recommendations to the field, the Society for Immunotherapy of Cancer reconvened the Immune Biomarkers Task Force. As a part of this Task Force, Working Group 3 (WG3) consisting of multidisciplinary experts from industry, academia, and government focused on the systematic assessment of immune regulation and modulation. In this review, the tumor microenvironment, microbiome, bone marrow, and adoptively transferred T cells will be used as examples to discuss the type and timing of sample collection. In addition, potential types of measurements, assays, and analyses will be discussed for each sample. Specifically, these recommendations will focus on the unique collection and assay requirements for the analysis of various samples as well as the high-throughput assays to evaluate potential biomarkers

HIV efficiently infects T cells from the endometrium and remodels them to promote systemic viral spread.

The female reproductive tract (FRT) is the most common site of infection during HIV transmission to women, but viral remodeling complicates characterization of cells targeted for infection. Here, we report extensive phenotypic analyses of HIV-infected endometrial cells by CyTOF, and use a 'nearest neighbor' bioinformatics approach to trace cells to their original pre-infection phenotypes. Like in blood, HIV preferentially targets memory CD4+ T cells in the endometrium, but these cells exhibit unique phenotypes and sustain much higher levels of infection. Genital cell remodeling by HIV includes downregulating TCR complex components and modulating chemokine receptor expression to promote dissemination of infected cells to lymphoid follicles. HIV also upregulates the anti-apoptotic protein BIRC5, which when blocked promotes death of infected endometrial cells. These results suggest that HIV remodels genital T cells to prolong viability and promote viral dissemination and that interfering with these processes might reduce the likelihood of systemic viral spread

HIV efficiently infects T cells from the endometrium and remodels them to promote systemic viral spread.

The female reproductive tract (FRT) is the most common site of infection during HIV transmission to women, but viral remodeling complicates characterization of cells targeted for infection. Here, we report extensive phenotypic analyses of HIV-infected endometrial cells by CyTOF, and use a 'nearest neighbor' bioinformatics approach to trace cells to their original pre-infection phenotypes. Like in blood, HIV preferentially targets memory CD4+ T cells in the endometrium, but these cells exhibit unique phenotypes and sustain much higher levels of infection. Genital cell remodeling by HIV includes downregulating TCR complex components and modulating chemokine receptor expression to promote dissemination of infected cells to lymphoid follicles. HIV also upregulates the anti-apoptotic protein BIRC5, which when blocked promotes death of infected endometrial cells. These results suggest that HIV remodels genital T cells to prolong viability and promote viral dissemination and that interfering with these processes might reduce the likelihood of systemic viral spread