Authorial Voice, Implied Audiences and the Drafting of the 1988 AIDS National Mailing

Dr. Veeder analyzes changes throughout many drafts of the 1988 ANM and finds that the process of negotiated drafting contributed to its success. She also concludes that risk communicators should focus attention on audience needs rather than competing truth claims

Nickel/tin coating protects threaded fasteners in corrosive environment

Threaded fasteners used in corrosive environments are plated with electroless nickel and electroplated, over the nickel, with tin. This provides a corrosion-resistant coating for the fasteners

Improved pH buffering agent for sodium hypochlorite

Sodium citrate/citric acid was found to be an effective buffer for pH control when used with sodium hypochlorite. The mixture does not corrode aluminum. The buffer appears to form a type of conversion coating that may provide corrosion-resistant properties to aluminum in other applications

Infrared observations of asteroids from earth and space

Infrared reflectances at wavelength between 1 and 4 micrometers are used for determining asteroid surface mineralogy, surface composition, diameters, and albedos. Thermal models were developed for analyzing infrared observations at longer wavelengths. The discovery of a spectral feature due to water of hydration on Ceres seems to contradict the mineralogy inferred from spectrophotometry

Positioning adolescents in literacy teaching and learning

Secondary literacy instruction often happens to adolescents rather than with them. To disrupt this trend, we collaborated with 12th-grade “literacy mentors” to reimagine literacy teaching and learning with 10th-grade mentees in a public high school classroom. We used positioning theory as an analytic tool to (a) understand how mentors positioned themselves and how we positioned them and (b) examine the literacy practices that enabled and constrained the mentor position. We found that our positioning of mentors as collaborators was taken up in different and sometimes unexpected ways as a result of the multiple positions available to them and institutional-level factors that shaped what literacy practices were and were not negotiable. We argue that future collaborations with youth must account for the rights and duties of all members of a classroom community, including how those rights and duties intersect, merge, or come into conflict within and across practices.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was supported by a Faculty Research Award from the School of Education at Boston University. (Faculty Research Award from the School of Education at Boston University)Accepted manuscrip

IRAS asteroid families

The Infrared Astronomical Satellite (IRAS) sampled the entire asteroid population at wavelengths from 12 to 100 microns during its 1983 all sky survey. The IRAS Minor Planet Survey (IMPS) includes updated results for more recently numbered as well as other additional asteroids with reliable orbital elements. Albedos and diameters were derived from the observed thermal emission and assumed absolute visual magnitudes and then entered into the IMPS database at the Infrared Processing and Analysis Center (IPAC) for members of the Themis, Eos, Koronis and Maria asteroid families and compared with their visual colors. The IMPS results for the small (down to about 20 km) asteroids within these major families confirm trends previously noted for their larger members. Each of these dynamical families which are defined by their similar proper elements appears to have homogeneous physical properties

The rotation of Io predicted by the Poincar\'e-Hough model

This note tackles the problem of the rotation of Io with the 4-degrees of freedom Poincar\'e-Hough model. Io is modeled as a 2-layer body, i.e. a triaxial fluid core and a rigid outer layer. We show that the longitudinal librations should have an amplitude of about 30 arcseconds, independent of the composition of the core. We also estimate the tidal instability of the core, and show that should be slowly unstable.Comment: arXiv admin note: text overlap with arXiv:1111.301

Albedo heterogeneity on the surface of (1943) Anteros

We have investigated the effect of rotation on the polarization of scattered light for the near-Earth asteroid (1943) Anteros using the Dual Beam Imaging Polarimeter on the University of Hawaii's 2.2 m telescope. Anteros is an L-type asteroid that has not been previously observed polarimetrically. We find weak but significant variations in the polarization of Anteros as a function of rotation, indicating albedo changes across the surface. Specifically, we find that Anteros has a background albedo of p_v = 0.18 +/- 0.02 with a dark spot of p_v < 0.09 covering < 2% of the surface.Comment: Accepted to Icarus, 15 pages, 3 fig

Rectified Asteroid Albedos and Diameters from IRAS and MSX

Rectified diameters and albedo estimates of 1517 main belt asteroid selected from the IRAS and MSX asteroid photometry catalogues are derived from updated infrared thermal models, the Standard Thermal Model (STM) and the Near Earth Asteroid Thermal Model (NEATM), and Monte Carlo simulations, using new Minor Planet Center (MPC) compilations of absolute magnitudes (H-values) constrained by occultation and radar derived parameters. The NEATM approach produces a more robust estimate of albedos and diameters, yielding albedos of $p_{v}$(NEATM mean)$=0.081 \pm 0.064$. The asteroid beaming parameter ($\eta$) for the selected asteroids has a mean value of $1.07 \pm 0.27$, and the smooth distribution of $\eta$ suggests that this parameter is independent of asteroid properties such as composition. No trends in $\eta$ due to size-dependent rotation rates are evident. Comparison of derived $\eta$'s as a function of taxonomic type indicates the beaming parameter values for S-type and C-type asteroids are identical within the standard deviation of the population of beaming parameters.Comment: 43 pages in manuscript layout, 9 figures. Submitted to The Astronomical Journa