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During late March and April of 1999 the University of Wyoming's King Air research aircraft measured atmospheric concentrations of NO, O3, peroxyacetyl nitrate (PAN), CO, CH4, VOCs, aerosols, and J(NO2) off the west coast of the United States. During 14 flights, measurements were made between 39°-48° N latitude, 125°-129° W longitude, and at altitudes from 0-8 km. These flights were part of the Photochemical Ozone Budget of the Eastern North Pacific Atmosphere (PHOBEA) experiment, which included both ground-based and airborne measurements. Flights were scheduled when meteorological conditions minimized the impact of local pollution sources. The resulting measurements were segregated by air mass source region as indicated by back isentropic trajectory analysis. The chemical composition of marine air masses whose 5-day back isentropic trajectories originated north of 40° N latitude or west of 180° W longitude (WNW) differed significantly from marine air masses whose 5-day back isentropic trajectories originated south of 40° N latitude and east of 180° W longitude (SW). Trajectory and chemical analyses indicated that the majority of all encountered air masses, both WNW and SW, likely originated from the northwestern Pacific and have characteristics of emissions from the East Asian continental region. However, air masses with WNW back trajectories contained higher mixing ratios of NO, NOx, O3, PAN, CO, CH4, various VOC pollution tracers, and aerosol number concentration, compared to those air masses with SW back trajectories. Calculations of air mass age using two separate methods, photochemical and back trajectory, are consistent with transport from the northwestern Pacific in 8-10 days for air masses with WNW back trajectories and 16-20 days for air masses with SW back trajectories. Correlations, trajectory analysis, and comparisons with measurements made in the northwestern Pacific during NASA's Pacific Exploritory Mission-West Phase B (PEM-West B) experiment in 1994 are used to investigate the data. These analyses provide evidence that anthropogenically influenced air masses from the northwestern Pacific affect the overall chemical composition of the northeastern Pacific troposphere. Copyright 2001 by the American Geophysical Union.

As part of the Photochemical Ozone Budget of the Eastern North Pacific Atmosphere (PHOBEA) project, we made observations of CO, O3, NOx, peroxyacetyl nitrate (PAN), nonmethane hydrocarbons (NMHC), Rn, aerosol scattering, aerosol absorption, and aerosol number density during the springs of 1997 and 1998 at the Cheeka Peak Observatory (CPO) on the western tip of Washington State. The data have been segregated to quantify the mixing ratio of these species in the Pacific marine atmosphere. However, even in these marine air masses, there are occasionally substantial enhancements of NOx and aerosols, but not CO, which we attribute to diesel exhaust from ship traffic to and from major ports in the region. The marine air masses were further classified into four categories based on 10-day back isentropic trajectories; high, mid, and low latitude and those which had crossed over the Asian industrial region. Mean marine mixing ratios in 1998 were significantly higher then the 1997 values for CO (1997 mean equal to 151, 1998 mean equal to 170 ppbv), ethane (1771, 1968 parts per trillion by volume (pptv)), and ethyne (306, 452 pptv). Also, segregation of the 1998 data by air mass origin produced smaller differences in the mixing ratios for most species when comparing different source regions. We attribute both of these results to elevated emissions associated with unusually large areas of biomass burning which took place in Indonesia and Siberia during late 1997 and 1998. The relative enhancements of CO, ethane, ethyne, and propane we observed at CPO are consistent with enhanced biomass burning and industrial sources in the spring of 1998, relative to the spring of 1997. Copyright 2001 by the American Geophysical Union.

Canister sampling for the determination of atmospheric mixing ratios of nonmethane hydrocarbons (NMHCs), selected halocarbons, and methyl nitrate was conducted aboard the National Center for Atmospheric Research (NCAR) C-130 aircraft over the Pacific and Southern Oceans as part of the First Aerosol Characterization Experiment (ACE 1) during November and December 1995. A latitudinal profile, flown from 76°N to 60°S, revealed latitudinal gradients for most trace gases. NMHC and halocarbon gases with predominantly anthropogenic sources, including ethane, ethyne, and tetrachloroethene, exhibited significantly higher mixing ratios in the northern hemisphere at all altitudes. Methyl chloride exhibited its lowest mixing ratios at the highest northern hemisphere latitudes, and the distributions of methyl nitrate and methyl iodide were consistent with tropical and subtropical oceanic sources. Layers containing continental air characteristic of aged biomass burning emissions were observed above about 3 km over the remote southern Pacific and near New Zealand between approximately 19°S and 43°S. These plumes originated from the west, possibly from fires in southern Africa. The month-long intensive investigation of the clean marine southern midlatitude troposphere south of Australia revealed decreases in the mixing ratios of ethane, ethyne, propane, and tetrachloroethene, consistent with their seasonal mixing ratio cycle. By contrast, increases in the average marine boundary layer concentrations of methyl iodide, methyl nitrate, and dimethyl sulfide (DMS) were observed as the season progressed to summer conditions. These increases were most appreciable in the region south of 44°S over Southern Ocean waters characterized as subantarctic and polar, indicating a seasonal increase in oceanic productivity for these gases. Copyright 1999 by the American Geophysical Union.

Using observations from the Cheeka Peak Observatory in northwestern Washington State during March-April, 1997, we show that Asian anthropogenic emissions significantly impact the concentrations of a large number of atmospheric species in the air arriving to North America during spring. Isentropic back-trajectories can be used to identify possible times when this impact will be felt, however trajectories alone are not sufficient to indicate the presence of Asian pollutants. Detailed chemical and meteorological data from one of these periods (March 29th, 1997) indicates that the surface emissions were lifted into the free troposphere over Asia and then transported to North America in ~6 days.

Fifty-eight African American children (grades 4-6) responded to the Test of Core Knowledge, a divergent task that required free associations about mainstream and African American topics. Participants' knowledge of both mainstream and African American cultural items increased significantly between grades 4 and 5. (Contains references.) (CR)

The Northwest Regional Educational Laboratory's Equity Center has identified several disturbing trends, including renewed physical separation, cultural biases, lower teacher expectations, and ability grouping, resulting in inequitable policies and practices and unsatisfactory student achievement. Seven key ameliorative components, including access to resources, are identified. (Contains 11 references.) (MLH)

A study of 743 disabled and nondisabled youth in inclusionary outdoor programs at 12 resident camps and 2 resident outdoor schools found that disabled youth significantly increased their social interactions with peers and their active participation in the program. Youth without disabilities improved their social interactions and developed greater understanding and respect for persons different than themselves. (TD)

To test the language experience hypothesis, the comprehension of high-, moderate-, and low-familiarity idioms was examined in 24 African-American and 24 European-American fifth graders. Results indicated a significant effect of group on idioms rated as low-familiarity. The influence of social and regional culture on idiom comprehension is discussed. (Author/DB)

This study examined effects of text genre and repeated reading on written language comprehension in younger (mean age 21) and older (mean age 72) healthy adults. Although reading time was significantly faster for younger adults, there were appreciable influences of text genre and repeated reading on measures of text processing and comprehension in both groups. (DB)

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Background: Identifying associations or links between encoded stimuli can influence whether those stimuli are successfully retrieved at a later time. Aims: The purpose of this study was to investigate the influence of semantic and phonological lexical targets on recall in individuals with mild to moderate traumatic brain injury (TBI) and to identify if individuals with TBI form associations when recalling related information. Methods & Procedures: Forty-seven individuals, 14 with TBI, completed the Deese–Roediger–McDermott (DRM) word retrieval paradigm in which six digitally recorded word lists were presented auditorily. Three of the lists contained semantically related words and three contained phonologically related words. Outcomes & Results: Non-brain-injured (NBI) participants recalled significantly more phonological and semantic stimuli than participants with TBI. Phonologically related stimuli resulted in increased intrusions for both TBI and NBI participants. For participants with TBI, age and time post injury were not significantly correlated with performance on the DRM paradigm, though the number of semantically related items recalled was moderately correlated with performance on standardised assessments. Though TBI participants recalled fewer words, they appeared to utilise recall strategies in a manner similar to NBI peers with intrusion data suggesting that both groups were forming associations between words. Conclusions: Individuals with mild to moderate TBI successfully identify associations between encoded stimuli and used those associations when recalling target information. [ABSTRACT FROM AUTHOR]

Performance on the Rey-Auditory Verbal Learning (R-AVL) and ReyOsterrieth Complex Figure Design (R-0 CFD) tests was examined in patients (N= 94) with dementia of the Alzheimer's type (DAT) and closed head injury (CHI). On the R-AVL, DAT patients demonstrated considerably greater impairment than CHI patients, along with a flat learning/retention curve that showed negligible improvement with repeated trials, recency effects only, and an excessive number of word intrusions (confabulation) on the recognition trial. CHI patients demonstrated both a recency and primacy effect along with improvement over repeated trials (positive slope learning curve). Both groups demonstrated impairment R-0 CFD recall; the DAT group again displayed substantially greater copying and recall deficits. Clinical guidelines are given for the use of the R-AVL and R-0 CFD for these two patient populations.