1,548 research outputs found
BLESSED IS SHE WHO DANCES FOR JUSTICE AND PEACE
Carla De Sola, a Juilliard-educated dancer, choreographer, teacher, and author, has led sacred dance on issues of peace, the environment, and social justice. Dance and the arts can lead lamentation in the face of evil and nurture imagination and creativity. The fear that leads to violence is often irrational and prompted by emotions. Arts can help to illumine and to heal feelings. The ideas of Teilhard de Chardin, SJ, influenced De Sola and led to the name Omega Liturgical Dance Company. De Chardin’s ideas underlie her extensive use of dance based on caring for creation including the annual St. Francis’ day Earth Mass which annually draws about 5,000 to the Cathedral of St. John the Divine. It began in 1985 and continues to this day. Whether dancing for peace with the Soviets or the Irish or leading people in anti-nuclear demonstrations, De Sola’s compassion and grace allure people to follow her lead
Ab initio study of magnetic anisotropy of M-type hexaferrite thin films
Ferrites are a broad class of oxide materials with a wide range oftechnologically important applications. The M-type hexaferrites, ofwhich BaFe12O19 is taken as a prototype compound, show particular promise as very high density magnetic and magneto-optical datastorage media. There are still serious gaps in the understanding ofthe fundamental origins of, and mechanisms governing, the magneticproperties of these materials. The detailed relationships between theseproperties and the material structure over nanometre length scales arealso not fully understood. This thesis addresses both of these pressingissues. It describes first a detailed ab initio theoretical treatment ofthe origins and magnitudes of the two most important mechanismswhich give rise to magnetic anisotropy, namely dipolar interactionsand single-ion contributions. The thesis outlines the theory of thesetwo types of magnetic interactions in solid insulating oxide materials.It also describes the theory of the deposition and growth of thin films,and the implementation of both branches of this theoretical studyin a set of original computer programs developed and refined duringthis study, comprising tools for both calculation and visualization. Anovel growth model and efficient Monte Carlo techniques are used toinvestigate and quantify the dependence on growth conditions of thestructure of thin films of hexaferrite materials. The magnetic theory is also implemented in a flexible and powerful program, which isused in turn to comprehensively investigate the structural dependenceof magnetic properties in the bulk crystalline material, idealized thinfilms, and finally by the simulated grown films. The influence of filmstructure on volume and surface contributions to the anisotropy ofthin films is thereby quantified and discussed
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MRL1: Emory Warren Ross Papers, 1877-1971
Treasurer of Disciples of Christ Congo Mission (1908); Secretary/Treasurer of Union Mission House (1909); Disciples of Christ missionary (1912-1916); Secretary of Conseil Protestant du Congo (1925-1933); Secretary of African Welfare Committee of the Federal Council of Churches and American Committee of Work in the Congo (1933-1936); Executive Secretary of African Committee of the National Council of Churches of Christ U.S.A. (1936-1953); Collection contains publications, articles, newspaper clippings, pamphlets, reports, minutes, maps, photos, and personal correspondence
Flip rearrangement in the water pentamer: Analysis of electronic structure
Tunneling pathways of the flip rearrangement between permutation-inversion isomers corresponding to the energetically degenerate global energy minima of (H2O)5 are analyzed in terms of the electronic structure. We demonstrate that charge density-based scalar measures quantify the responses of the bonding to the flip rearrangement and we discovered a high degree of continuity of the values that depend on the presence of the sliding motion of the bond critical point relative to the oxygen atom. The scalar measures can distinguish the pairs of permutation-inversion isomers everywhere except at the transition state due to the asymmetrical energy barrier; however, they cannot determine the most and least facile directions of the flip rearrangement. The vector or directional character of the two sides of the pathway is captured by the stress tensor trajectories constructed in a non-Cartesian space, defined by the variation of the position of the bond critical point. The stress tensor trajectories are presented in terms that enable bond-flexing, bond-twist, and bond-anharmonicity of the flip rearrangement between permutation-inversion isomers to be quantified. The stress tensor trajectories can distinguish the isomers at the transition state and demonstrate that the clockwise and counter-clockwise directions of the flip rearrangement are the most and least facile respectively
Ectopic lymphoid follicles: inducible centres for generating antigen-specific immune responses within tissues
Lymphoid neogenesis is traditionally viewed as a pre-programmed process that promotes the formation of lymphoid organs during development. Here, the spatial organization of T and B cells in lymph nodes and spleen into discrete structures regulates antigen-specific responses and adaptive immunity following immune challenge. However, lymphoid neogenesis is also triggered by chronic or persistent inflammation. Here, ectopic (or tertiary) lymphoid organs frequently develop in inflamed tissues as a response to infection, auto-immunity, transplantation, cancer or environmental irritants. Although these structures affect local immune responses, the contribution of these lymphoid aggregates to the underlining pathology are highly context dependent and can elicit either protective or deleterious outcomes. Here we review the cellular and molecular mechanisms responsible for ectopic lymphoid neogenesis and consider the relevance of these structures in human disease
Thermal Testing of a Stacked Core Mirror for UV Applications
The ASTRO2010 Decadal Survey stated that an advanced large-aperture ultraviolet, optical, near-infrared (UVOIR) telescope is required to enable the next generation of compelling astrophysics and exoplanet science; and, that present technology is not mature enough to affordably build and launch any potential UVOIR mission concept. Under Science and Technology funding, NASA's Marshall Space Flight Center and ITT Exelis have developed a more cost effective process to make 4m monolithic spaceflight UV quality, low areal density, thermally and dynamically stable primary mirrors. A proof of concept mirror was built and tested down to 250K which would allow imaging out to 2.5 microns. This mirror was thermally tested at the Marshall Spaceflight Center to understand the thermal changes between the processing temperature of 293K and the potential low end of the operational temperature of 250K. Isothermal testing results and front plate gradient results have been evaluated and compared to analysis predictions. Measurement of gravity effects on surface figure will be compared to analytical predictions. Future testing of a larger Pathfinder mirror will also be discussed
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