32,052 research outputs found
Deep Studies of the Resolved Stellar Populations in the Outskirts of M31
We discuss the first results from ongoing studies of the resolved stellar
populations in the outskirts of our nearest large neighbour, M31. Deep
HST/WFPC2 archival observations are used to construct colour-magnitude-diagrams
which reach well below the horizontal branch at selected locations in the outer
disk and halo, while a panoramic ground-based imaging survey maps spatial
density variations through resolved star counts to a projected radius of ~50
kpc.Comment: 4 pages, to appear in proc of "New Quests in Stellar Astrophysics:
The Link Between Stars and Cosmology", eds. M. Chavez, A. Bressan, A.
Buzzoni, D. Mayy
BulB - visualizing bulletin board activity
Visualisation is well known as an effective means of enriching user interaction with complex systems. Recent research with online communities has considered the application of visualisation tool support, with the intention of further improving communication between community members. This paper reviews existing work in this area with specific reference to the application of visualisation to improve user interaction within online forums such as bulletin boards. The paper then outlines work undertaken by the authors to develop a second-generation visualisation tool - 'BulB'
The Behavior of Soluble Salt in Sharkey Clay
Soluble salt problems do exist and are significant in Arkansas. Studies have been conducted on Crowley silt loam (Typic Albaqualfs) which have established the behavior of soluble salt in that soil. The major objective of this study was to quantify the behavior of soluble salt in a second important Mississippi River Delta soil - the Sharkey (Vertic Haplaquepts). To this end, estimation of the downward redistribution of salt and the estimation of various components of the water balance for this soil served as specific objectives. Field studies were designed to monitor the movement of salt in the Sharkey soil and to characterize selected components of the water balance. In total, three tentative conclusions may be drawn from the data. First, the infiltration for the Sharkey soil was approximately three times that of the Crowley silt loam. The average value was 29 cm for the rice season. Second, levee seepage, while significant for small plots, was shown to be small for production-sized fields. Levee seepage remained relatively constant throughout the season and averaged 0.025 nvfym/d. And third, downward redistribution of salt was large and appeared to follow a pattern where a peak occurred at the surface and, possibly, at the lower soil depths
Measurements of Surface Diffusivity and Coarsening During Pulsed Laser Deposition
Pulsed Laser Deposition (PLD) of homoepitaxial SrTiO3 was studied with
in-situ x-ray specular reflectivity and surface diffuse x-ray scattering.
Unlike prior reflectivity-based studies, these measurements access both the
time- and the length-scales of the evolution of the surface morphology during
growth. In particular, we show that this technique allows direct measurements
of the diffusivity for both inter- and intra-layer transport. Our results
explicitly limit the possible role of island break-up, demonstrate the key
roles played by nucleation and coarsening in PLD, and place an upper bound on
the Ehrlich-Schwoebel (ES) barrier for downhill diffusion
Developing collaborative partnerships with culturally and linguistically diverse families during the IEP process
Family participation in the special education process has been federally mandated for 40 years, and educators recognize that effective collaboration with their students’ families leads to improved academic and social outcomes for students. However, while some family-school relationships are positive and collaborative, many are not, particularly for culturally and linguistically diverse (CLD) families. This article provides practice guidelines based in research for teachers who seek to improve their practices when working with CLD families who have children served by special education
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