2,635 research outputs found
What Is Essential Is Invisible To The Eye : Culturally Responsive Teaching As A Key To Unlocking Children\u27s Multiple Literacies
Refugee students, language learners, and students in poverty are often viewed through a deficit model of everything they do not have in the way of school preparedness. However, many of them are survivors who possess courage and resilience. They also possess exceptional visual literacy developed through experiences with video and other images. Leveraging their visual literacy builds a bridge to help them understand text, which in turn helps them understand how literature reflects all of our experiences. Increased textual literacy helps students engage with vexing human questions. These questions form an inquiry base from which students can approach writing as an authentic task for self-expression. Student voice and culturally responsive teaching is valued in this model, which counters the experiences with failure that so many immigrant and low-income students learn when standardized testing is the focus of school. Inviting students to co-create literate spaces honors them, their families, and their cultures
Empirical Perspectives on Mediation and Malpractice
The use of mediation in the medical malpractice context is examined. The impact of any court-related alternative dispute resolution program is also discussed
Gravitationally lensed image simulations for the study of the substructure in galaxy clusters
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2005.Includes bibliographical references (p. 49-50).As gravitational lensing is susceptible to all gravitating matter-both baryonic and dark-it provides a potentially clean way to study the mass distribution of galaxy clusters. We are particularly interested in the substructure of dark matter in galaxy clusters as it signals constraints on various cosmological parameters as well as cluster evolution. Gravitationally lensed image simulations are needed in order to determine just how much can be learned from current mass reconstruction methods. We present here a comprehensive procedure for generating such a set of simulated images using shapelets (Massey et al. (2005)). These images use a catalog of galaxies from the Hubble Space Telescope data taken as part of the Cosmos Evolution Survey (COSMOS). The background galaxies are then lensed by a 1015M galaxy cluster set at a redshift of z = 0.4. Noise and a point spread function (PSF) can also be added to the images; we chose to emulate the set of COSMOS pointings from the Subaru Telescope. As the shapelets simulation software allows complete freedom over all background galaxy, noise, and PSF parameters, the methods presented here have the potential to be used to not only verify that existing mass reconstruction algorithms work, but also to help optimize specifications on future telescopes.(cont.) We also present a preliminary strong lensing analysis of two noise- and PSF-free simulated images according to the algorithm presented in Diego et al. (2005). We found that while this procedure was able to accurately reproduce the surface mass density profile for radii greater than that of the outermost arcs used in the analysis, it failed in unexpected ways for the inner radii.by Mossy S. Peeples.S.B
Thermostructural applications of heat pipes
The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight
Evolution of the atomic and molecular gas content of galaxies in dark matter haloes
We present a semi-empirical model to infer the atomic and molecular hydrogen
content of galaxies as a function of halo mass and time. Our model combines the
SFR-halo mass-redshift relation (constrained by galaxy abundances) with
inverted SFR-surface density relations to infer galaxy H I and H2 masses. We
present gas scaling relations, gas fractions, and mass functions from z = 0 to
z = 3 and the gas properties of galaxies as a function of their host halo
masses. Predictions of our work include: 1) there is a ~ 0.2 dex decrease in
the H I mass of galaxies as a function of their stellar mass since z = 1.5,
whereas the H2 mass of galaxies decreases by > 1 dex over the same period. 2)
galaxy cold gas fractions and H2 fractions decrease with increasing stellar
mass and time. Galaxies with M* > 10^10 Msun are dominated by their stellar
content at z < 1, whereas less-massive galaxies only reach these gas fractions
at z = 0. We find the strongest evolution in relative gas content at z < 1.5.
3) the SFR to gas mass ratio decreases by an order of magnitude from z = 3 to z
= 0. This is consistent with lower H2 fractions; these lower fractions in
combination with smaller gas reservoirs correspond to decreased present-day
galaxy SFRs. 4) an H2-based star- formation relation can simultaneously fuel
the evolution of the cosmic star-formation and reproduce the observed weak
evolution in the cosmic HI density. 5) galaxies residing in haloes with masses
near 10^12 Msun are most efficient at obtaining large gas reservoirs and
forming H2 at all redshifts. These two effects lie at the origin of the high
star-formation efficiencies in haloes with the same mass.Comment: accepted for publication in MNRAS, 20 pages, 16 figures (+ 1 figure
in appendix), data files are accessible through
http://www.eso.org/~gpopping/Gergo_Poppings_Homepage/Data.htm
Artificial atmosphere control system
Two-gas control system has been developed which uses existing hardware. Three systems are used for control, monitoring, and safety backup. Pure oxygen will be supplied to maintain safe pressure level should something go wrong
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