Gasoline cars produce more carbonaceous particulate matter than modern filter-equipped diesel cars.

Carbonaceous particulate matter (PM), comprising black carbon (BC), primary organic aerosol (POA) and secondary organic aerosol (SOA, from atmospheric aging of precursors), is a highly toxic vehicle exhaust component. Therefore, understanding vehicle pollution requires knowledge of both primary emissions, and how these emissions age in the atmosphere. We provide a systematic examination of carbonaceous PM emissions and parameterisation of SOA formation from modern diesel and gasoline cars at different temperatures (22, -7 °C) during controlled laboratory experiments. Carbonaceous PM emission and SOA formation is markedly higher from gasoline than diesel particle filter (DPF) and catalyst-equipped diesel cars, more so at -7 °C, contrasting with nitrogen oxides (NOX). Higher SOA formation from gasoline cars and primary emission reductions for diesels implies gasoline cars will increasingly dominate vehicular total carbonaceous PM, though older non-DPF-equipped diesels will continue to dominate the primary fraction for some time. Supported by state-of-the-art source apportionment of ambient fossil fuel derived PM, our results show that whether gasoline or diesel cars are more polluting depends on the pollutant in question, i.e. that diesel cars are not necessarily worse polluters than gasoline cars.

Essential practices as adults read to meet the needs of deaf or hard of hearing students.

Most deaf or hard of hearing students do not read proficiently (Karchmer, Milone, & Wolk, 1979; Allen, 1986), yet Winzer (1985) found no agreement as to the best way to teach reading to them. We reviewed the literature in related fields in an attempt to assist teachers and parents in identifying practices that are supported by research and linked to literacy attainment. We were especially impressed by the work of Adams (1990) with regard to the practices that promote proficient reading in hearing students, as well as by that of Hoggan and Strong (1994), who studied the techniques of those working with students with language disabilities. The result of our review was a rationale and description of ten practices that we suggest are essential to include when reading to students if they are to become proficient readers themselves. Our work is particularly applicable when adults are using the methods of read aloud, adult/student shared reading, and adult guided reading. These essential practices can be modeled by teachers for parents and others working with students as they develop reading skills.

In-service trends. General education teachers working with educational interpreters.

The "inclusion" movement has resulted in a shift of placement for children who are deaf or hard of hearing. Over 50% of students who are deaf or hard of hearing are now attending academic classes with hearing students in public school settings (Schildroth & Hotto, 1993). As the enrollment of deaf and hard of hearing students in public schools continues to increase, so does the need for qualified educational interpreters. The present study was designed to investigate nationwide the in-service training that general-education teachers receive with regard to the roles and responsibilities of educational interpreters. One hundred elementary and secondary general education teachers were surveyed, yielding a 59% return rate. Less than 33% of those teachers who returned surveys had attended in-services on the topic of educational interpreters. Neither the academic level (i.e., elementary and secondary) of the teachers who participated or the number of students who were deaf or hard of hearing and in attendance at a school influenced the number of in-services provided on the topic of interpreting.