1,720,977 research outputs found
Direct effects of waterpipe tobacco smoking on cardiovascular health
No full textIntroduction
Waterpipe smoking is characterized by long sessions of smoking, deep inhalation of tobacco smoke, and longer puffs compared to cigarette smoking. Clearly, waterpipe smokers are exposed to high levels of tobacco smoke. Waterpipe smoke contains carcinogens and toxicants, such as tobacco-specific nitrosamines, benzene, nitric oxide and heavy metals. Nicotine impact on hemodynamic responses is evident by increase in heart rate, constriction in blood vessels, and increase in myocardial contraction which contribute to acute cardiovascular events.
Methods
This secondary analysis was completed using data from a randomized clinical trial to investigate the direct effects of nicotine (published elsewhere). Twenty-four young adults smoked waterpipe tobacco for 45 minutes in a controlled environment once a week for 4 weeks. Carbon Monoxide was measured pre and post smoking. Heart rate was measured continuously during smoking. The two nicotine conditions were placebo and nicotine tobacco.
Results
Heart rate increased significantly over time while smoking nicotine containing waterpipe tobacco. The mean heart rate increased from 78 ± 12 (at baseline) to 86 ± 13 (post smoking) in the nicotine condition and from 72 ± 11 (baseline) to 77 ± 9 (post smoking) in the non-nicotine condition. CO levels increased significantly from pre smoking (1.18 ± 1.05) to post smoking (16.83 ± 12.45) in the nicotine condition and the increase was significant (t = 6.18, p <.00). Also, CO levels increased from pre smoking (1.27 ± .93) to post smoking (19.62 ± 12.64) in the non-nicotine condition and the increase was significant (t = 6.89, p <.00).
Funding
Washington State University Alcohol and Drug Abuse Research Program
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The role of behavioral therapy in treating waterpipe addiction
No full textBackground
To date, very few smoking cessation interventions
targeting waterpipe tobacco smoking have been reported worldwide.
Methods
Thirty-one adults completed the study. Participants
were adults 18 years of age and older who smoked tobacco using a waterpipe
three times or more per week for the past one year, did not smoke cigarettes,
and were not planning on quitting waterpipe tobacco smoking. Design: A two-group,
repeated measures (10 study visits on Mondays and Thursdays) design was used.
Participants were randomly assigned to either the contingent (n = 19) or non-contingent (n
=20) study arms.
Intervention: Contingent participants received monetary incentives based on negative
salivary cotinine results. Earning incentives started at
0.50 for a maximum $192.50. Non-contingent participants earned incentives
independent of salivary cotinine results. Participants in both study
arms had the opportunity to earn the same amount of money. The primary study
outcomes were biochemically verified prolonged abstinence and 7-day point
prevalence.
Results
The prolonged abstinence rate in the contingent and non-contingent groups were 61% and 6%, respectively, (p ˂ 0.001). The 7-day point prevalence in the contingent and non-contingent were 47% and 5%, respectively, (p = 0.003). The odds of abstinence were 17.10 (95% CI=1.89, 154.84) times greater for the contingent group than for the non-contingent group.
Conclusions
The preliminary results support further
examination of contingency management as a strategy for
initially motivating unwilling waterpipe smokers to quit
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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