120 research outputs found
City of Fort Myers Proclamation
NSU 50th Anniversaryhttps://nsuworks.nova.edu/nsudigital_proclamations/1019/thumbnail.jp
The Fort Myers Plan
Fort Myers, Florida
The Fort Myers plan, The Planning Board, Fort Myers, Florida. Herbert S. Swan City Planner, New York. George W. Tuttle, Engineer Erwin T. Muller, Associate City Planners. [The Board?, 1926?
The mass profile of early-type galaxies in overdense environments: the case of the double source plane gravitational lens SL2SJ02176-0513
SL2SJ02176-0513 is a remarkable lens for the presence of two multiply-imaged
systems at different redshifts lensed by a foreground massive galaxy at : a bright cusp arc at and an additional
double-image system at an estimated redshift of based on
photometry and lensing geometry. The system is located about 400 kpc away from
the center of a massive group of galaxies. Mass estimates for the group are
available from X-ray observations and satellite kinematics. Multicolor
photometry provides an estimate of the stellar mass of the main lens galaxy.
The lensing galaxy is modeled with two components (stars and dark matter), and
we include the perturbing effect of the group environment, and all available
constraints. We find that classic lensing degeneracies, e.g. between external
convergence and mass density slope, are significantly reduced with respect to
standard systems and infer tight constraints on the mass density profile: (i)
the dark matter content of the main lens galaxy is in line with that of typical
galaxies ; (ii) the required mass
associated with the dark matter halo of the nearby group is consistent with
X-ray and weak-lensing estimates (); (iii)
accounting for the group contribution in the form of an external convergence,
the slope of the mass density profile of the main lens galaxy alone is found to
be , consistent with the isothermal ()
slope. We demonstrate that multiple source plane systems together with good
ancillary dataset can be used to disentangle local and environmental effects.Comment: 10 pages, 6 figures, submitted to A&
Evidence for Paracrine Protective Role of Exogenous αA-Crystallin in Retinal Ganglion Cells
Expression and secretion of neurotrophic factors have long been known as a key mechanism of neuroglial interaction in the central nervous system. In addition, several other intrinsic neuroprotective pathways have been described, including those involving small heat shock proteins such as α-crystallins. While initially considered as a purely intracellular mechanism, both αA-crystallins and αB-crystallins have been recently reported to be secreted by glial cells. While an anti-apoptotic effect of such secreted αA-crystallin has been suggested, its regulation and protective potential remain unclear. We recently identified residue threonine 148 (T148) and its phosphorylation as a critical regulator of αA-crystallin intrinsic neuroprotective function. In the current study, we explored how mutation of this residue affected αA-crystallin chaperone function, secretion, and paracrine protective function using primary glial and neuronal cells. After demonstrating the paracrine protective effect of αA-crystallins secreted by primary Müller glial cells (MGCs), we purified and characterized recombinant αA-crystallin proteins mutated on the T148 regulatory residue. Characterization of the biochemical properties of these mutants revealed an increased chaperone activity of the phosphomimetic T148D mutant. Consistent with this observation, we also show that exogeneous supplementation of the phosphomimetic T148D mutant protein protected primary retinal neurons from metabolic stress despite similar cellular uptake. In contrast, the nonphosphorylatable mutant was completely ineffective. Altogether, our study demonstrates the paracrine role of αA-crystallin in the central nervous system as well as the therapeutic potential of functionally enhanced αA-crystallin recombinant proteins to prevent metabolic-stress induced neurodegeneration
Discrete approaches to quantum gravity in four dimensions
The construction of a consistent theory of quantum gravity is a problem in
theoretical physics that has so far defied all attempts at resolution. One
ansatz to try to obtain a non-trivial quantum theory proceeds via a
discretization of space-time and the Einstein action. I review here three major
areas of research: gauge-theoretic approaches, both in a path-integral and a
Hamiltonian formulation, quantum Regge calculus, and the method of dynamical
triangulations, confining attention to work that is strictly four-dimensional,
strictly discrete, and strictly quantum in nature.Comment: 33 pages, invited contribution to Living Reviews in Relativity; the
author welcomes any comments and suggestion
Cosmological Applications of Gravitational Lensing
The last decade has seen an enormous increase of activity in the field of
gravitational lensing, mainly driven by improvements of observational
capabilities. I will review the basics of gravitational lens theory, just
enough to understand the rest of this contribution, and will then concentrate
on several of the main applications in cosmology. Cluster lensing, and weak
lensing, will constitute the main part of this review.Comment: 26 pages, including 2 figures (a third figure can be obtained from
the author by request) gziped and uuencoded postscript file; to be published
in Proceedings of the Laredo Advanced Summer School, Sept. 9
Titling community land to prevent deforestation: An evaluation of a best-case program in Morona-Santiago, Ecuador
Assigning land title to collective landholders is one of the primary policies land management agencies use to avoid deforestation worldwide. Such programs are designed to improve the ability of landholders to legally exclude competing users and thereby strengthen incentives to manage forests for long-term benefits. Despite the prevalence of this hypothesis, findings about the impacts of land titling programs on deforestation are mixed. Evidence is often unreliable because programs are targeted according to factors that independently influence the conversion of forests. We evaluate a donor-funded land titling and land management program for indigenous communities implemented in Morona-Santiago, Ecuador. This program offers a close to best case scenario for a land titling program to reduce deforestation because of colonization pressure, availability of payments when titled communities maintain forests, and limited opportunities for commercial agriculture. We match plots in program areas with similar plots outside program areas on covariates that influence the conversion of forests. Based on matched comparisons, we do not find evidence that land titling or community management plans reduced forest loss in the five years following legal recognition. The results call into question land titling as a direct deforestation strategy and suggests land titling is better viewed a precursor to other programs. (C) 2015 The Authors. Published by Elsevier Ltd
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