This study examines the impact of standards-based professional development on teacher efficacy and instructional practice of elementary and middle school science teachers. Professional development activities were conducted over a period of 3 years and included content courses as well as teacher involvement in professional learning communities. Teacher efficacy was assessed at five time points using the Science Teacher Efficacy Beliefs Instrument (STEBI), and instructional practice was evaluated at four time points with classroom observations using the Reformed Teaching Observation Protocol (RTOP). Results indicate that there was significant growth in teacher self-efficacy but not in outcome expectancy. There was also significant growth in the extent to which teachers implemented inquiry-based instruction in the classroom. Additionally, a positive correlation was observed between changes in self-efficacy and changes in the use of inquiry-based instructional practice. These results are discussed in terms of a model of teacher learning wherein changes in teacher beliefs and changes in classroom practice mutually influence each other, and also in terms of the impact of collaboration on teacher efficacy and practice. ß

Antimicrobial, cytolytic, and cell-penetrating peptides induce pores or perturbations in phospholipid membranes that result in fluxes of dyes into or out of lipid vesicles. Here we examine the fluxes induced by four of these membrane-active peptides in giant unilamellar vesicles. The type of flux is determined from the modality of the distributions of vesicles as a function of their dye content using the statistical Hartigan dip test. Graded and all-or-none fluxes correspond to unimodal and bimodal distributions, respectively. To understand how these distributions arise, we perform Monte Carlo simulations of peptide-induced dye flux into vesicles using a very simple model. The modality of the distributions depends on the rate constants of pore opening and closing, and dye flux. If the rate constants of pore opening and closing are both much smaller than that of dye flux through the pore, all-or-none influx occurs. However, if one of them, especially the rate constant for pore opening, increases significantly relative to the flux rate constant, the process becomes graded. In the experiments, we find that the flux type is the same in giant and large vesicles, for all peptides except one. But this one exception indicates that the flux type cannot be used to unambiguously predict the mechanism of membrane permeabilization by the peptides.

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Instrument choice is a crucial part of evaluation of professional development programmes. The use of multiple evaluation methods helps in triangulation, and offers insight into the developmental sequence involved in the changes in teacher beliefs and practice. Most current instruments are self-contained and not designed for use in conjunction with other instruments. Linking such instruments poses challenges for evaluators. We performed an extensive literature survey to identify instruments best aligned with each other. We describe here our evaluation needs, examine the subset of instruments selected based upon these needs, and discuss our choice of instruments guided by specific principles.

Objective. This study is intended to enhance the discussion of environmental equity by offering a methodology that is based on chemical-specific risk zones that reflect inventories of chemical facilities, risk dispersion modeling, local weather conditions, and the unique chemical processes of each site. The central question concerns whether the racial makeup of a community near a chemical-processing site is characteristic of the city, county, or community as a whole. In essence, does the racial makeup of a community vary by distance from a chemical-processing facility? Methods. A comparison of the racial makeup of the community was examined for 13 chemical-processing sites submitting off-site consequence data under the Environmental Protection Agency Risk Management Plan, by clusters of the sites, and for all sites in the community. Instead of relative ratios, we look at odds ratios. The odds ratio compares the odds of being African American to the odds of being nonAfrican American at two given distance classes. In this way we may make inferences about how much higher (or lower) are the odds of an African American (relative to a non-African American) living in a closer distance class (as opposed to a further distance class). Results. The results show that as one moves further from a facility, the characteristics of the community reflect less and less the makeup near the site. The percentage of African Americans living near a chemical-processing site tends to be much higher when compared to population characteristics further from the site. Conclusions. The study shows that distance does make a significant difference in the racial characteristics of the population from a chemical-processing site. Using data reflecting accidental-release scenarios, weather conditions, and the chemical process

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IQs on the WAIS and WAIS–R of 23 women and 22 men showed means on the former to be higher than on the latter and some difference in relative contribution of subtests to over-all IQ.