346 research outputs found
Attitudes towards potential new tobacco control regulations among U.S. adults
Favorable attitudes towards tobacco control policies can facilitate their implementation and success. We examined attitudes toward four potential U.S. Federal tobacco regulations (banning menthol from cigarettes, reducing nicotine levels in cigarettes, banning candy and fruit flavored electronic cigarettes, and banning candy and fruit flavored little cigars and cigarillos) and associations with individual and state variables. A nationally representative phone survey of 4337 adults assessed attitudes toward potential policies. Weighted logistic regression was used to assess relationships between attitudes and demographic factors, smoking behavior, beliefs about the government (knowledge, trust, and credibility), exposure to tobacco control campaigns, and state variables from the US Centers for Disease Control and Prevention (CDC) State Tobacco Activities Tracking and Evaluation (STATE) System. Most respondents supported three out of four policies. Respondents that were female, non-white, Latino, living below the poverty line, had less than high school education, were of older age, did not smoke, had higher trust in government, and were exposed to national tobacco control campaigns had higher odds of expressing favorable attitudes toward potential new tobacco regulations than did their counterparts. No state-level effects were found. While differences in attitudes were observed by individual demographic characteristics, behaviors, and beliefs, a majority of participants supported most of the potential new tobacco regulations surveyed
Should the legal age for tobacco be raised? Results from a national sample of adolescents
Raising the minimum age of legal access to tobacco products may reduce smoking initiation and save lives. In a national telephone survey (2014-2015), US adolescents aged 13 to 17 years (N = 1,125; response rate, 66%) were asked about raising the age of legal access to tobacco products and randomized to hear one of 3 ages (19, 20, or 21 y). Most adolescents, across all US regions, favored raising the minimum age of legal access to 19 (75.7%), 20 (80.6%), or 21 (76.4%). These supportive attitudes may be useful to tobacco prevention and control practitioners who seek to reduce tobacco use among adolescents
Incidence and control of bovine gastrointestinal nematodes in the East of the Province of La Pampa, Argentina
A cross-sectional survey including 350 stocking farms and bovine establishments that operate the full cycle (FC) as well as fattening operations (IN) was carried out in the East of the Province of La Pampa to record cases of verminous gastroenteritis (VGE) as well as control and management practices applied by the farmers.Farms were stratified by herd size into three categories: more than 900 (G), 900-500 (M) and 500-300 (P) bovines. Samples from each category were collected at random. 33% of the farmers surveyed indicated that their animals had been affected by clinical cases of VGE with morbidity and mortality rates between 11.2% and 0.42%, respectively. More cases of VEG (P<0.004, X2 8.33) occurred in herds on FC establishments (37%) that on fattening farms (IN) (21%); the relative risk (RR) was 1.77 (95%; IC 1.18 â 2.74) but no differences were noted between categories. Ninety-four percent of the farmers use avermectins alone (AVM) (71%) or combined with benzimidazole (BZD, 20%) or levamisole (3%); 6% use BZD alone. The percentage of use of other drugs in addition to AVM increases (P<0.005, X2 7.80) with larger herds (G: 32%, M: 21%, P: 15%). Of the treatments, 95.2% include avermectins alone in injectable form (82.6%) or combined with oral (16.5%) or intraruminal (0.9%) forms. Approximately 2.42 treatments per year are performed and are more prevalent (P<0.01) in G and IN farms (2.7 treatments). 35% of the farmers deworm twice a year, in the fall (between March and July) and in late winter-spring (between August and October-), 16% deworm only once (between February and April) and 12% twice (between late summer and early winter). 18% of the farmers (G: 24%, M: 18%; P: 13%) prevent VGE losses by administering treatment at a specific time of the year. 60% of the farmers consult the veterinarian although only 29% perform an egg count (hpg) although differences (P<0.001) between herd sizes were noted: G: 41%, M: 26%; P 19%. 12% (FC 10%; IN 16%). 12% of the farmers (FC 10%; IN 16%) perform a follow-up of parasite infections with an egg count and administer treatment based on this monitoring and the recommendation of a veterinarian. 94% of those surveyed indicated that VGE alone (55%) or in conjunction with other pathologies were a major problem and 30% said it was the main health problem. The study shows the economic importance of GIPs for the competitiveness of the systems in the region. The use of a significant quantity of anthelmintics, mainly avermectins, and a low participation of veterinarians in planning the controls were observed. A trend indicating that large farms and fattening operations assign more importance to control, use of anthelmintics and participation of professionals was noted
Spin and energy transfer in nanocrystals without transport of charge
We describe a mechanism of spin transfer between individual quantum dots that
does not require tunneling. Incident circularly-polarized photons create
inter-band excitons with non-zero electron spin in the first quantum dot. When
the quantum-dot pair is properly designed, this excitation can be transferred
to the neighboring dot via the Coulomb interaction with either {\it
conservation} or {\it flipping} of the electron spin. The second dot can
radiate circularly-polarized photons at lower energy. Selection rules for spin
transfer are determined by the resonant conditions and by the strong spin-orbit
interaction in the valence band of nanocrystals. Coulomb-induced energy and
spin transfer in pairs and chains of dots can become very efficient under
resonant conditions. The electron can preserve its spin orientation even in
randomly-oriented nanocrystals.Comment: 13 pages, 3 figure
Macroscopic resonant tunneling of magnetic flux
We have developed a quantitative theory of resonant tunneling of magnetic
flux between discrete macroscopically distinct quantum states in SQUID systems.
The theory is based on the standard density-matrix approach. Its new elements
include the discussion of the two different relaxation mechanisms that exist
for the double-well potential, and description of the ``photon-assisted''
tunneling driven by external rf radiation. It is shown that in the case of
coherent flux dynamics, rf radiation should lead to splitting of the peaks of
resonant flux tunneling, indicating that the resonant tunneling is a convenient
tool for studying macroscopic quantum coherence of flux.Comment: 11 pages, 8 figure
Effects of framing proximal benefits of quitting and motivation to quit as a query on communications about tobacco constituents
Introduction: Little is known on how to communicate messages on tobacco constituents to tobacco users. This study manipulated three elements of a message in the context of a theorybased communication campaign about tobacco constituents: (1) latency of response efficacy (how soon expected health benefits would accrue), (2) self-efficacy (confidence about quitting), and (3) interrogative cue ("Ready to be tobacco-free?"). Methods: Smokers (N = 1669, 55.4% women) were recruited via an online platform, and were randomized to a 3 (Latency of response efficacy) Ă 2 (Self-efficacy) Ă 2 (Interrogative cue) factorial design. The dependent variables were believability, credibility, perceived effectiveness of the communication message, and action expectancies (likelihood of seeking additional information and help with quitting). Results: Latency of response efficacy influenced believability, perceived effectiveness, credibility, and action expectancies. In each case, scores were higher when specific health benefits were said to accrue within 1 month, as compared to general health benefits occurring in a few hours. The interrogative cue had a marginal positive effect on perceived effectiveness. The selfefficacy manipulation had no reliable effects, and there were no significant interactions among conditions. Conclusions: Smokers appear less persuaded by a communication message on constituents where general health benefits accrue immediately (within a few hours) than specific benefits over a longer timeframe (1 month). Additionally, smokers appeared to be more persuaded by messages with an interrogative cue. Such findings may help design more effective communication campaigns on tobacco constituents to smokers. Implications: This paper describes, for the first time, how components of tobacco constituent messages are perceived. We now know that smokers appear to be less persuaded by communication messages where general health benefits accrue immediately (within a few hours) than specific benefits over a longer timeframe (1 month). Additionally, including an interrogative cue ("Ready to be tobacco free?") may make messages more effective, whereas the self-efficacy manipulation designed to increase confidence about quitting had no effect. While messages were universally impactful across smoker subpopulations, everyday smokers and smokers with less trust in the government may be less receptive to communication campaigns
Quantum theory of resonantly enhanced four-wave mixing: mean-field and exact numerical solutions
We present a full quantum analysis of resonant forward four-wave mixing based
on electromagnetically induced transparency (EIT). In particular, we study the
regime of efficient nonlinear conversion with low-intensity fields that has
been predicted from a semiclassical analysis. We derive an effective nonlinear
interaction Hamiltonian in the adiabatic limit. In contrast to conventional
nonlinear optics this Hamiltonian does not have a power expansion in the fields
and the conversion length increases with the input power. We analyze the
stationary wave-mixing process in the forward scattering configuration using an
exact numerical analysis for up to input photons and compare the results
with a mean-field approach. Due to quantum effects, complete conversion from
the two pump fields into the signal and idler modes is achieved only
asymptotically for large coherent pump intensities or for pump fields in
few-photon Fock states. The signal and idler fields are perfectly quantum
correlated which has potential applications in quantum communication schemes.
We also discuss the implementation of a single-photon phase gate for continuous
quantum computation.Comment: 10 pages, 11 figure
Full quantum solutions to the resonant four-wave mixing of two single-photon wave packets
We analyze both analytically and numerically the resonant four-wave mixing of
two co-propagating single-photon wave packets. We present analytic expressions
for the two-photon wave function and show that soliton-type quantum solutions
exist which display a shape-preserving oscillatory exchange of excitations
between the modes. Potential applications including quantum information
processing are discussed.Comment: 7 pages, 3 figure
Cigarette constituent health communications for smokers: Impact of chemical, imagery, and source
Introduction: Communication campaigns are incorporating tobacco constituent messaging to reach smokers, yet there is a dearth of research on how such messages should be constructed or will be received by smokers. Methods: In a 2 Ă 2 Ă 2 experiment, we manipulated three cigarette constituent message components: (1) the toxic constituent of tobacco (arsenic vs. lead) with a corresponding health effect, (2) the presence or absence of an evocative image, and (3) the source of the message (FDA vs. no source). We recruited smokers (N = 1669, 55.4% women) via an online platform and randomized them to one of the eight message conditions. Participants viewed the message and rated its believability and perceived effectiveness, the credibility of the message source, and action expectancies (ie, likelihood of seeking additional information and help with quitting as a result of seeing the message). Results: We found significant main effects of image, constituent, and source on outcomes. The use of arsenic as the constituent, the presence of an evocative image, and the FDA as the source increased the believability, source credibility, and perceived effectiveness of the tobacco constituent health message. Conclusions: Multiple elements of a constituent message, including type of constituent, imagery, and message source, impact their reception among smokers. Specifically, communication campaigns targeting smokers that utilize arsenic as the tobacco constituent, visual imagery, and the FDA logo may be particularly effective in changing key outcomes that are associated with subsequent attitude and behavioral changes. Implications: This article describes how components of communication campaigns about cigarette constituents are perceived. Multiple elements of a tobacco constituent message, including type of constituent, image, and message source may influence the reception of messages among current smokers. Communication campaigns targeting smokers that utilize arsenic as the tobacco constituent, visual imagery, and the FDA logo may be particularly effective in changing key outcomes among smokers. The effects of such campaigns should be examined, as well as the mechanisms through which such campaigns affect change
Public knowledge and credibility perceptions of the FDA as a tobacco regulator
efforts that increase the public's understanding of the FDA's role as a tobacco regulator may positively impact views of the agency's credibility. This may in turn improve public reception to the FDA's messages and regulations. Implications This study is the first to show nationally representative estimates of both knowledge and credibility of the FDA as a tobacco regulator. Our research shows further that knowledge of the FDA's tobacco regulatory roles is likely to be an important factor related to perceived credibility of the FDA. Increasing the public's knowledge of the FDA's roles may enhance the agency's credibility, which can improve public reception to messages and regulations.Introduction Since the U.S. Food and Drug Administration (FDA) was granted regulatory authority over tobacco products in 2009, few studies have examined perceived credibility of the FDA in this role. The current study assessed knowledge and credibility of the FDA as a regulator of tobacco products. Methods In a nationally representative survey of U.S. adults (N = 4758), we assessed knowledge that the FDA regulates the manufacture, distribution, and marketing of cigarettes, and credibility of the FDA as a tobacco regulator. We examined demographic differences in knowledge and credibility, and associations of knowledge and trust in government with credibility perceptions. Results Less than half of respondents reported knowing the FDA regulates how cigarettes are sold (46.8%) and advertised (49.7%), and only 36.0% knew the FDA regulates how cigarettes are made, with few demographic differences. Respondents reported that the FDA was moderately credible in regulating tobacco. Knowledge of the FDA as a tobacco regulator and trust in government were the strongest predictors of credibility. Being of younger age, being White (compared to African American), and being male were associated with higher credibility ratings of the FDA. Conclusions Much of the public still does not know that the FDA regulates tobacco products, and credibility perceptions are moderate. Greater knowledge of the FDA's regulatory role was associated with higher credibilit
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