3,237 research outputs found
Civic Service Worldwide: Defining a Field, Building a Knowledge Base.
In this article, the authors summarize results of a global assessment of civic service. Searching by country and using information from organizational memberships, publications, and the Internet, 210 civic service programs were identified in 57 countries
Galaxy destruction and diffuse light in clusters
Deep images of the Centaurus and Coma clusters reveal two spectacular arcs of
diffuse light that stretch for over 100 kpc, yet are just a few kpc wide. At a
surface brightness of m_b \sim 27-28th arcsec^-2, the Centaurus arc is the most
striking example known of structure in the diffuse light component of a rich
galaxy cluster. We use numerical simulations to show that the Centaurus feature
can be reproduced by the tidal debris of a spiral galaxy that has been tidally
disrupted by the gravitational potential of NGC 4709. The surface brightness
and narrow dimensions of the diffuse light suggest that the disk was
co-rotating with its orbital path past pericentre. Features this prominent in
clusters will be relatively rare, although at fainter surface brightness levels
the diffuse light will reveal a wealth of structure. Deeper imaging surveys may
be able to trace this feature for several times its presently observed extent
and somewhere along the tidal debris, a fraction of the original stellar
component of the disk will remain bound, but transformed into a faint
spheroidal galaxy. It should be possible to confirm the galactic origin of the
Centaurus arc by observing planetary nebulae along its length with redshifts
close to that of NGC 4709.Comment: Replaced with version accepted by MNRAS (Dec. 1999): Added missing
reference (to pg. 4 & reference list). Section 3 shortened; removed three
figures. Now 8 pages long, with 8 figures. Low resolution images included,
high resolution version available at
http://star-www.dur.ac.uk:80/~calcaneo/cenarc.htm
Carlos Ichter, Alan Moore, and Kale Magness in a Joint Junior Voice Recital
This is the program for the joint junior voice recital of baritone Carlos Ichter, baritone Alan Moore, and baritone Kale Magness. Pianist Linda Tapson accompanied Ichter; pianist Lisa Nevin accompanied Moore; and pianist Susan White accompanied Magness. The recital took place on March 26, 1982, in the Mabee Fine Arts Center Recital Hall
Civic Service Worldwide: Social Development Goals and Partnerships
Civic service is a long-term, intensive form of volunteering. This article reports on a global assessment of civic service, which identified 210 programs in 57 countries. Program goals and administrative partnerships suggest that civic service is a social development intervention. For civic service to achieve its potential, research is recommended regarding server inclusivity, goal accomplishment, and the nature and effect of partnerships
Influence of anisotropy on velocity and age distribution at Scharffenbergbotnen blue ice area
We use a full-Stokes thermo-mechanically coupled ice-flow model to study the dynamics of the glacier inside Scharffenbergbotnen valley, Dronning Maud Land, Antarctica. The domain encompasses a high accumulation rate region and, downstream a sublimation-dominated bare ice ablation area. The ablation ice area is notable for having old ice at its surface since the vertical velocity is upwards, and horizontal velocities are almost stagnant there. We compare the model simulation with field observations of velocities and the age distribution of the surface ice. A satisfactory match with simulations using an isotropic flow law was not found because of too high horizontal velocities and too slow vertical ones. However, the existence of a pronounced ice fabric may explain the present day surface velocity distribution in the inner Scharffenbergbotnen blue ice area. Near absence of data on the temporal evolution of Scharffenbergbotnen since the Late Glacial Maximum necessitates exploration of the impact of anisotropy using prescribed ice fabrics: isotropic, single maximum, and linear variation with depth, in both two-dimensional and three dimensional flow models. The realistic velocity field simulated with a non-collinear orthotropic flow law, however produced surface ages in significant disagreement with the few reliable age measurements and suggests that the age field is not in a steady state and that the present distribution is a result of a flow reorganization at about 15 000 yr BP. In order to fully understand the surface age distribution a transient simulation starting from the Late Glacial Maximum including the correct initial conditions for geometry, age, fabric and temperature distribution would be needed. It is the first time that the importance of anisotropy has been demonstrated in the ice dynamics of a blue ice area. This is useful to understand ice flow in order to better interpret archives of ancient ice for paleoclimate research
Chaotic Coupling Constants
We examine some novel physical consequences of the general structure of
moduli spaces of string vacua. These include (1) finiteness of the volume of
the moduli space and (2) chaotic motion of the moduli in the early universe. To
fix ideas we examine in detail the example of the (conjectural) dilaton-axion
``-duality'' of four-dimensional string compactifications. The facts (1) and
(2) together might help to solve some problems with the standard scenarios for
supersymmetry breaking and vacuum selection in string theory.Comment: 18 pages (4 figs), YCTP-P2-94, RU-94-2
Youth Volunteerism and Civic Service in Latin America and the Caribbean: A Potential Strategy for Social and Economic Development
Youth Volunteerism and Civic Service in Latin America and the Caribbean: A Potential Strategy for Social and Economic Developmen
Two Higgs doublet dynamics at the electroweak phase transition: a non-perturbative study
Using a three-dimensional (3d) effective field theory and non-perturbative
lattice simulations, we study the MSSM electroweak phase transition with two
dynamical Higgs doublets. We first carry out a general analysis of spontaneous
CP violation in 3d two Higgs doublet models, finding that this part of the
parameter space is well separated from that corresponding to the physical MSSM.
We then choose physical parameter values with explicit CP violation and a light
right-handed stop, and determine the strength of the phase transition. We find
a transition somewhat stronger than in 2-loop perturbation theory, leading to
the conclusion that from the point of view of the non-equilibrium constraint,
MSSM electroweak baryogenesis can be allowed even for a Higgs mass mH \approx
115 GeV. We also find that small values of the mass parameter mA (\lsim 120
GeV), which would relax the experimental constraint on mH, do not weaken the
transition noticeably for a light enough stop. Finally we determine the
properties of the phase boundary.Comment: 56 pages, 16 figures; small clarifications added, concerning e.g.
Higgs mass bounds; to appear in NP
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Syndemics and the PrEP Cascade: Results from a Sample of Young Latino Men Who Have Sex with Men.
Young Latino men who have sex with men (MSM) are a highly vulnerable population for HIV infection. Pre-exposure prophylaxis (PrEP) is a novel biomedical HIV prevention tool that may aid in reducing the disparity in HIV incidence among Latino MSM. However, PrEP use is disproportionally low among Latino MSM and, therefore, identifying barriers along the PrEP continuum of care (the "PrEP cascade") would provide insight into how to best deploy PrEP interventions. Syndemics theory is a prominent framework employed in HIV prevention; however, to date, no known studies have applied this theory to PrEP. Thus, the aim of the current study was to explore the association between syndemics and the PrEP cascade, including the degree to which psychosocial and structural syndemic constructs are related to the PrEP cascade. Participants were 151 young Latino MSM (M age = 24 years; SD = 3) residing in San Diego, California, who completed a battery of online self-report measures. Results indicated high levels of syndemic indicators and varying levels of engagement across the PrEP cascade. As syndemic indicators increased, the odds of engagement across the PrEP cascade were significantly lowered. Psychosocial and structural syndemic factors accounted for unique variance in the PrEP cascade. Results highlight the need for combination interventions that address both psychosocial and structural barriers to PrEP use and persistence among young Latino MSM
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