3,585 research outputs found

    Shell Creek, Wyoming - 1973

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    In situ mass analysis of particles by surface ionization mass spectrometry

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    A qualitative study of the application of surface ionization and mass spectrometry to the in situ detection and constituent analysis of atmospheric particles was conducted. The technique consists of mass analysis of ions formed as a result of impingement of a stream of particles on a hot filament where, it is presumed, surface ionization takes place. Laboratory air particles containing K, Ca, and possibly hydrocarbons were detected. Other known particles such as Al2O3, Pb(NO3)2, and Cr2O3 were analyzed by detecting the respective metal atoms making up the particles. In some cases, mass numbers indicative of compounds making up the particles were detected showing surface ionization of particles sometimes leads to chemical analysis as well as to elemental analysis. Individual particles were detected, and it was shown that the technique is sensitive to Al2O3 particles with a mass of a few nanograms

    Striking characteristics of the magnetron ionization gage in helium from 1.9 times 10 to the minus 7 torr to 7 times 10 to the minus 10 torr

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    Striking characteristics of magnetron ionization gages in helium over low pressure rang

    Vidicon observations of Mars : images of the October, 1973 dust storm and two-dimensional narrow-band photometry.

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1975.Bibliography: leaves 69-70.M.S

    Geochemistry of Kauai shield-stage lavas: Implications for the chemical evolution of the Hawaiian plume

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    We measured He, Sr, Nd, Pb, and Os isotope ratios and major and trace element concentrations in stratigraphically and paleomagnetically controlled shield-stage lavas from Kauai, Hawaii. The range of 3He/4He ratios (17–28 RA) from Kauai is similar to that reported from Loihi and thus challenges the prevailing notion that high 3He/4He ratios are restricted to the preshield stage of Hawaiian magmatism. 3He/4He ratios vary erratically with stratigraphic position, and chronostratigraphic control from paleomagnetic data indicates very rapid changes in the 3He/4He ratios (up to 8 RA in ~102 years). These variations in helium isotopic ratios are correlated with variations in radiogenic isotope ratios, suggesting rapid changes in melt composition supplying the magma reservoir. A three-component mixing model, previously proposed for Hawaiian shield lavas, does not adequately explain the isotopic data in Kauai shield lavas. The addition of a depleted-mantle (DM) component with the isotopic characteristics similar to posterosional basalts explains the isotopic variability in Kauai shield lavas. The DM component is most apparent in lavas from the Kauai shield and is present in varying proportion in other Hawaiian shield volcanoes. Shield lavas from Kauai sample a high 3He/4He end-member (Loihi component), but while lavas from western Kauai have a larger contribution from the Kea component (high 206Pb/204Pb, anomalously low 207Pb/204Pb relative to 206Pb/204Pb), lavas from eastern Kauai have a larger proportion of an enriched (Koolau) component. The systematic isotopic differences between eastern and western Kauai reflect a gradual migration of the locus of volcanism from west to east, or alternatively east and west Kauai are two distinct shield volcanoes. In the latter case, the two shield volcanoes have maintained distinct magma supply sources and plumbing systems. Our new geochemical data from Kauai are consistent with the existence of a single high 3He/4He reservoir in the Hawaiian plume and suggest that the proportion of the different mantle components in the plume have changed significantly in the past 5 Myr. The long-term evolution of the Hawaiian plume and the temporal variability recorded in Kauai lavas require more complex geochemical heterogeneities than suggested by radially zoned plume models. These complexities may arise from heterogeneities in the thermal boundary layer and through variable entrainment of ambient mantle by the upwelling plume

    The Emotions of Teaching Through Service-Learning

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    Impact of hospital guideline for weight‐based antimicrobial dosing in morbidly obese adults and comprehensive literature review

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109281/1/jcpt12200.pd

    Interactive media for parental education on managing children chronic condition: a systematic review of the literature

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    BackgroundAlthough some research has examined the use of games for the education of pediatric patients, the use of technology for parental education seems like an appropriate application as it has been a part of the popular culture for at least 30years. The main objective of this systematic review is to examine the literature for research evaluating the use of interactive media in the education of parents of children with chronic conditions.MethodsWe searched the MEDLINE, PSYCHINFO, CINAHL, Cochrane database of systematic reviews and EMBASE databases from 1986 to 2014 seeking original investigations on the use of interactive media and video games to educate parents of children with chronic conditions. Cohort studies, randomized control trials, and observational studies were included in our search of the literature.Two investigators reviewed abstracts and full texts as necessary. The quality of the studies was assessed using the GRADE guidelines.Overall trend in the results and the degree of certainty in the results were considered when assessing the body of literature pertaining to our focused questions.ResultsOur initial search identified 4367 papers, but only 12 fulfilled the criterion established for final analysis, with the majority of the studies having flaws that reduced their quality. These papers reported mostly positive results supporting the idea that parent education is possible through interactive media.ConclusionWe found limited evidence of the effectiveness of using serious games and or interactive media to educate parents of children with chronic conditions.Electronic supplementary materialThe online version of this article (doi:10.1186/s12887-015-0517-2) contains supplementary material, which is available to authorized users
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