46 research outputs found

    Electronic cigarettes and nicotine dependence: evolving products, evolving problems

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    Electronic cigarettes (ECIGs) use an electric heater to aerosolize a liquid that usually contains propylene glycol, vegetable glycerin, flavorants, and the dependence-producing drug nicotine. ECIG-induced nicotine dependence has become an important concern, as some ECIGs deliver very little nicotine while some may exceed the nicotine delivery profile of a tobacco cigarette. This variability is relevant to tobacco cigarette smokers who try to switch to ECIGs. Products with very low nicotine delivery may not substitute for tobacco cigarettes, so that ECIG use is accompanied by little reduced risk of cigarette-caused disease. Products with very high nicotine delivery may make quitting ECIGs particularly difficult should users decide to try. For non-smokers, the wide variability of ECIGs on the market is especially troublesome: low nicotine products may lead them to initiate nicotine self-administration and progress to higher dosing ECIGs or other products, and those that deliver more nicotine may produce nicotine dependence where it was not otherwise present. External regulatory action, guided by strong science, may be required to ensure that population-level nicotine dependence does not rise

    Electronic cigarettes and nicotine dependence: evolving products, evolving problems

    Get PDF
    Electronic cigarettes (ECIGs) use an electric heater to aerosolize a liquid that usually contains propylene glycol, vegetable glycerin, flavorants, and the dependence-producing drug nicotine. ECIG-induced nicotine dependence has become an important concern, as some ECIGs deliver very little nicotine while some may exceed the nicotine delivery profile of a tobacco cigarette. This variability is relevant to tobacco cigarette smokers who try to switch to ECIGs. Products with very low nicotine delivery may not substitute for tobacco cigarettes, so that ECIG use is accompanied by little reduced risk of cigarette-caused disease. Products with very high nicotine delivery may make quitting ECIGs particularly difficult should users decide to try. For non-smokers, the wide variability of ECIGs on the market is especially troublesome: low nicotine products may lead them to initiate nicotine self-administration and progress to higher dosing ECIGs or other products, and those that deliver more nicotine may produce nicotine dependence where it was not otherwise present. External regulatory action, guided by strong science, may be required to ensure that population-level nicotine dependence does not rise

    ABET and development in the Northern Cape province: Assessing impacts of CACE courses, 1996-1999

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    This study presents the results of an investigation into the impact of CACE courses for adult educators, trainers and development practitioners. The report describes how the courses affected the training practices and lives of past students. Case studies document and analyse the problems and successes of implementing capacity-building ABET training in the Northern Cape.UK Department for International Development (DFID

    Atmospheric potential oxygen: New observations and their implications for some atmospheric and oceanic models

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    Measurements of atmospheric O2/N2 ratios and CO2 concentrations can be combined into a tracer known as atmospheric potential oxygen (APO ≈ O2/N2 + CO2) that is conservative with respect to terrestrial biological activity. Consequently, APO reflects primarily ocean biogeochemistry and atmospheric circulation. Building on the work of Stephens et al. (1998), we present a set of APO observations for the years 1996-2003 with unprecedented spatial coverage. Combining data from the Princeton and Scripps air sampling programs, the data set includes new observations collected from ships in the low-latitude Pacific. The data show a smaller interhemispheric APO gradient than was observed in past studies, and different structure within the hemispheres. These differences appear to be due primarily to real changes in the APO field over time. The data also show a significant maximum in APO near the equator. Following the approach of Gruber et al. (2001), we compare these observations with predictions of APO generated from ocean O2 and CO2 flux fields and forward models of atmospheric transport. Our model predictions differ from those of earlier modeling studies, reflecting primarily the choice of atmospheric transport model (TM3 in this study). The model predictions show generally good agreement with the observations, matching the size of the interhemispheric gradient, the approximate amplitude and extent of the equatorial maximum, and the amplitude and phasing of the seasonal APO cycle at most stations. Room for improvement remains. The agreement in the interhemispheric gradient appears to be coincidental; over the last decade, the true APO gradient has evolved to a value that is consistent with our time-independent model. In addition, the equatorial maximum is somewhat more pronounced in the data than the model. This may be due to overly vigorous model transport, or insufficient spatial resolution in the air-sea fluxes used in our modeling effort. Finally, the seasonal cycles predicted by the model of atmospheric transport show evidence of an excessive seasonal rectifier in the Aleutian Islands and smaller problems elsewhere. Copyright 2006 by the American Geophysical Union

    Birth outcomes in Colorado's undocumented immigrant population

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    BACKGROUND: The birth outcomes of undocumented women have not been systematically studied on a large scale. The growing number of undocumented women giving birth in the United States has important implications for clinical care and public health policy. The objective of this study was to describe birth outcomes of undocumented immigrants in Colorado. METHODS: Retrospective descriptive study of singleton births to 5961 undocumented women using birth certificate data for 1998–1999. RESULTS: Undocumented mothers were younger, less educated, and more likely to be single. They had higher rates of anemia, were less likely to gain enough weight, and less likely to receive early prenatal care. They were much less likely to use alcohol or tobacco. Undocumented women had a lower rate of low birth weight (5.3% v 6.5%, P < .001) or preterm infants (12.9% v 14.5%; p = .001). Undocumented women experienced higher rates of labor complications including excessive bleeding (2.3% v 0.8%, p < .001) and fetal distress (8.7% v 3.6%, p < .001). CONCLUSION: Undocumented women have lower rates of preterm delivery and low birth weight infants, but higher rates of pregnancy related risk factors. Higher prevalence of some risk factors which are amenable to medical intervention reveals the need for improved prenatal care in this group
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