Low-Loss All-Optical Zeno Switch in a Microdisk Cavity Using EIT

We present theoretical results of a low-loss all-optical switch based on electromagnetically induced transparency and the classical Zeno effect in a microdisk resonator. We show that a control beam can modify the atomic absorption of the evanescent field which suppresses the cavity field buildup and alters the path of a weak signal beam. We predict more than 35 dB of switching contrast with less than 0.1 dB loss using just 2 micro-Watts of control-beam power for signal beams with less than single photon intensities inside the cavity.Comment: Updated with new references, corrected Eq 2a, and added introductory text. 7 pages, 5 figures, 3 table

Identifying Promising Themes for Adolescent Vaping Warnings: A National Experiment

Introduction: Adolescent vaping remains a problem in the United States, yet little is known about what health warning themes most discourage vaping among adolescents. We sought to identify the most compelling themes for vaping warnings for US adolescents. Methods: Participants were a national probability sample of 623 US adolescents aged 13-17 years, recruited in the summer of 2020. Adolescents were randomized to one of the five warning message themes about the potential health effects of vaping: 1. chemical harms, 2. lung harms, 3. Coronavirus Disease 2019 (COVID-19) harms, 4. nicotine addiction, or 5. control (messages about vape litter). The primary outcome was perceived message effectiveness (PME; 3-item scale). Secondary outcomes were negative affect (fear), attention, anticipated social interactions, and message novelty. Results: Adolescents rated the chemical, lung, and COVID-19 harms warning messages higher on PME than nicotine addiction and control (all p <. 05), while nicotine addiction was rated higher than control (p <. 05). The chemical, lung, and COVID-19 harms warning themes also elicited greater negative affect than nicotine addiction and control (all p <. 05). For all other secondary outcomes, the COVID-19 harms warning message theme was rated higher than nicotine addiction and control (all p <. 05). Conclusion: Adolescents perceived warning message themes about lung, chemical and COVID-19 health effects of vaping as more effective than nicotine addiction. To discourage vaping, the FDA and others should communicate to youth about the health effects of vaping beyond nicotine addiction. Implications: Adolescents rated warning message themes about the lung, chemical, and COVID-19 health effects of vaping as more effective than nicotine addiction, while nicotine addiction was rated as more effective than control themes about vaping litter. To discourage vaping among adolescents, health messaging should expand message themes to communicate about a broader set of health effects of vaping beyond nicotine addiction

Understanding Why Pictorial Cigarette Pack Warnings Increase Quit Attempts

Background: Our randomized trial found that pictorial cigarette pack warnings elicited more quit attempts than text-only warnings. Purpose: In the current study, we sought to identify psychological mechanisms that explain why pictorial cigarette pack warnings change behavior. Methods: In 2014 and 2015, we recruited 2,149 adult smokers in NC and CA, USA. We randomly assigned smokers to receive on their cigarette packs for 4 weeks either a text-only warning (one of the USA's current warnings on the side of cigarette packs) or a pictorial warning (one of the USA's proposed text warnings with pictures on the top half of the front and back of cigarette packs). Results: Pictorial warnings increased attention to, reactions to, and social interactions about cigarette pack warnings (all p < .05). However, pictorial warnings changed almost no belief or attitude measures. Mediators of the impact of pictorial warnings included increased attention, negative affect, social interactions, thinking about the warning and harms of smoking, and intentions to quit (all p < .05). Analyses also found that pictorial warnings led to greater avoidance of the warnings, which was associated with more quit attempts (p < .05). Conclusions: Pictorial warnings increased quit attempts by eliciting aversive reactions and by keeping the message vividly in smokers' minds. Contrary to predictions from several theories of health behavior, the warnings exerted little of their influence through changes in beliefs and attitudes and none of their influence through changes in risk perception. We propose the Tobacco Warnings Model based on these findings

Examining the Longitudinal Relationship Between Perceived and Actual Message Effectiveness: A Randomized Trial

We sought to examine the relationship between perceived message effectiveness (PME) and actual message effectiveness (AME) in a 3-week randomized trial of vaping prevention advertisements. Participants were US adolescents (n = 1,514) recruited in 2021. We randomly assigned them to view The Real Cost vaping prevention ads or control videos online. Participants viewed three videos at Visit 1, again at Visits 2 and 3, and completed a survey at each visit that assessed AME (susceptibility to vaping) and two types of PME–effects perceptions (potential for behavioral impact) and message perceptions (potential for message processing). At Visit 4, AME was measured. Compared to control, The Real Cost ads led to improved AME (lower susceptibility to vaping at Visit 4, p <.001). This was anticipated by The Real Cost ads eliciting higher PME ratings (higher effects and message perceptions at Visit 1, both p <.001). Furthermore, PME (both effects and message perceptions) at Visit 1 predicted susceptibility to vaping at Visits 1, 2, 3, and 4 (all p <.001). Finally, effects perceptions fully mediated the impact of The Real Cost ads on susceptibility to vaping (β = −.30; p <.001), while message perceptions only partially mediated the effect (β = −.04; p =.001). Our findings indicate a relationship between PME and AME, especially effects perceptions, and suggest that PME may be useful in message pre-testing to select messages with greater behavior change potential

Development of the UNC Perceived Message Effectiveness Scale for Youth

PURPOSE: Tobacco prevention media campaigns are an important tool to address youth tobacco use. We developed a theory-based perceived message effectiveness (PME) Scale to use when vetting messages for campaigns. METHODS: Participants were a national sample of N=623 US adolescents (ages 13-17 years) recruited from a national probability-based panel. In an online experiment, we randomised adolescents to view tobacco prevention ads. All participants viewed an ad on smoking or vaping from the US Food and Drug Administration's The Real Cost campaign and a control video, in a random order. After ad exposure, we assessed PME using nine candidate items and constructs for convergent and criterion validity analyses. We used confirmatory factor analysis and examined information curves to select the scale items. RESULTS: A brief PME scale with three items (α=0.95) worked equally well for demographically diverse adolescents with different patterns of tobacco use. The Real Cost ads generated higher PME scores than the control videos for both vaping and smoking (convergent validity; p<0.05). Higher PME scores were associated with greater attention, fear, cognitive elaboration and anticipated social interactions (convergent validity; r=0.31-0.66), as well as more negative attitudes toward and lower susceptibility to vaping and smoking (criterion validity; r=-0.14 to -0.37). A single-item PME measure performed similarly to the three-item version. CONCLUSIONS: The University of North Carolina PME Scale for Youth is a reliable and valid measure of the potential effectiveness of vaping and smoking prevention ads. Employing PME scales during message development and selection may help youth tobacco prevention campaigns deploy more effective ads

Impact of Vaping Prevention Advertisements on US Adolescents: A Randomized Clinical Trial

Importance: Understanding whether prevention advertisements reduce susceptibility to vaping is important owing to concerning levels of adolescent vaping. Objective: To examine whether vaping prevention advertisements from the US Food and Drug Administration (FDA) national Real Cost campaign lead to lower susceptibility to vaping among adolescents. Design, Setting, and Participants: For this 3-group randomized clinical trial with parallel assignment, participants were US adolescents aged 13 to 17 years who were susceptible to vaping or current e-cigarette users, recruited from online panels. Adolescents were randomized to 1 of 2 Real Cost vaping prevention trial groups (health harms- or addiction-themed advertisements) or to a control group (investigator-created neutral videos about vaping). Adolescents completed 4 weekly online surveys at visits 1 to 4 over a 3-week period. Data were analyzed from December 1, 2021, to August 25, 2022. Interventions: Adolescents saw 3 randomly ordered 30-second video advertisements online at each of 3 weekly study visits (visits 1, 2, and 3). Main Outcomes and Measures: The primary trial outcome was susceptibility to vaping. Surveys also assessed susceptibility to smoking cigarettes to examine any spillover effects of vaping prevention advertisements on smoking outcomes. Both susceptibility measures had 3 items and ranged from 1 (indicating not susceptible) to 4 (indicating highly susceptible). The primary analyses compared Real Cost groups (combined) with the control group, while exploratory analyses compared the Real Cost groups with each other. Results: Participants were 1514 adolescents (1140 [75.3%] boys; mean [SD] age, 15.22 [1.18] years), including 504 randomized to the Real Cost health harms group, 506 randomized to the Real Cost addiction group, and 504 randomized to the control group. Adolescents in the Real Cost groups (combined) had lower susceptibility to vaping at visit 4 than those in the control group (b = -0.21; 95% CI, -0.32 to -0.10). The Real Cost groups did not differ from one another on susceptibility to vaping (visit 4: b = -0.05; 95% CI, -0.17 to 0.07). Adolescents in the Real Cost groups (combined) also had lower susceptibility to smoking cigarettes than those in the control group (b = -0.21; 95% CI, -0.32 to -0.10). For both vaping and smoking, Real Cost groups had less positive attitudes (vaping: b = -0.27; 95% CI, -0.40 to -0.14; smoking: b = -0.23; 95% CI, -0.39 to -0.08) compared with the control group. Conclusions and Relevance: These findings suggest that vaping prevention advertisements from the FDA Real Cost campaign led to lower adolescent susceptibility to vaping and had beneficial spillover effects on cigarette smoking outcomes. Tobacco prevention campaigns can help reduce youth tobacco use. Trial Registration: ClinicalTrials.gov Identifier: NCT04836455

Adolescents' Understanding of Smoking and Vaping Risk Language: Cognitive Interviews to Inform Scale Development

Introduction: Perceived message effectiveness (PME) is a common metric to understand receptivity to tobacco prevention messages, yet most measures have been developed with adults. We examined adolescents' interpretation of language within candidate items for a new youth-targeted PME measure using cognitive interviewing. We sought to understand the meaning adolescents assigned to our candidate PME items to improve item wording. Aims and Methods: Participants were 20 adolescents, ages 13-17 years from the United States. Cognitive interviews used a structured guide to elicit feedback on comprehension, answer retrieval, and language regarding a set of Reasoned Action Approach-based survey items that assessed the PME of smoking and vaping prevention ads. We employed thematic analysis to synthesize findings from the interviews. Results: Interviews identified three main issues related to survey items: ambiguity of language, word choice (risk and other terminology), and survey item phrasing. Adolescents preferred direct, definitive language over more ambiguous phrasing which they saw as less serious (eg, "will"instead of "could"). For risk terminology, they preferred terms such as "harmful"and "dangerous"over "risky,"which was viewed as easy to discount. The term "negative effects"was interpreted as encompassing a broader set of tobacco harms than "health effects."Adolescents said that the term "vape"was preferable to "e-cigarette,"and identified ways to simplify item wording for greater clarity. Conclusions: Tobacco risk terms that appear similar differ in meaning to adolescents, and more direct and unambiguous language is preferred. Our findings informed changes to the PME scale items to improve clarity and reduce measurement error. Implications: This study adds to the literature on how adolescents interpret tobacco prevention language. Adolescents may interpret terminology differently than adults, which could lead to ambiguity in meaning and thus measurement error. Through cognitive interviewing, we identified and improved the language in a youth-focused PME measure for tobacco and vaping prevention

Reactions to messages about smoking, vaping and COVID-19: Two national experiments

Introduction The pace and scale of the COVID-19 pandemic, coupled with ongoing efforts by health agencies to communicate harms, have created a pressing need for data to inform messaging about smoking, vaping, and COVID-19. We examined reactions to COVID-19 and traditional health harms messages discouraging smoking and vaping. Methods Participants were a national convenience sample of 810 US adults recruited online in May 2020. All participated in a smoking message experiment and a vaping message experiment, presented in a random order. In each experiment, participants viewed one message formatted as a Twitter post. The experiments adopted a 3 (traditional health harms of smoking or vaping: Three harms, one harm, absent) × 2 (COVID-19 harms: one harm, absent) between-subjects design. Outcomes included perceived message effectiveness (primary) and constructs from the Tobacco Warnings Model (secondary: Attention, negative affect, cognitive elaboration, social interactions). Results Smoking messages with traditional or COVID-19 harms elicited higher perceived effectiveness for discouraging smoking than control messages without these harms (all p <0.001). However, including both traditional and COVID-19 harms in smoking messages had no benefit beyond including either alone. Smoking messages affected Tobacco Warnings Model constructs and did not elicit more reactance than control messages. Smoking messages also elicited higher perceived effectiveness for discouraging vaping. Including traditional harms in messages about vaping elicited higher perceived effectiveness for discouraging vaping (p <0.05), but including COVID-19 harms did not. Conclusions Messages linking smoking with COVID-19 may hold promise for discouraging smoking and may have the added benefit of also discouraging vaping

Impact of e-cigarette health warnings on motivation to vape and smoke

Background A prevailing hypothesis is that health warnings for electronic cigarettes (e-cigarettes) could drive people away from vaping and towards smoking cigarettes. We consider an alternative hypothesis that e-cigarette warnings discourage both vaping and smoking. Methods Participants were a national convenience sample of 2218 US adults who used e-cigarettes, cigarettes or both. In August 2018, we randomised participants to one of three warning types (control text about littering, text-only e-cigarette warning or pictorial e-cigarette warning). We further randomised participants viewing e-cigarette warnings to one of three topics (nicotine addiction, health hazards of use, or both health hazards and harms of use). The preregistered primary outcome was intentions to quit vaping among e-cigarette users. Secondary outcomes included interest in smoking and Tobacco Warnings Model constructs: attention, negative affect, anticipated social interactions and cognitive elaboration. Results Text warnings elicited higher intentions to quit vaping than control among e-cigarette users (d=0.44, p<0.001), and pictorial warnings elicited still higher intentions to quit vaping than text (d=0.12, p<0.05). Text warnings elicited lower interest in smoking compared with control among smokers (p<0.05); warnings had no other effects on interest in smoking among smokers or non-smokers. Text warnings about health hazards elicited higher intentions to quit vaping than nicotine addiction warnings. E-cigarette warnings also increased Tobacco Warnings Model constructs. Discussion E-cigarette health warnings may motivate users to quit vaping and discourage smoking. The most promising warnings include health hazards (other than nicotine addiction) and imagery. We found no support for the hypothesis that e-cigarette warnings could encourage smoking cigarettes

Questions of fairness and anti-doping in US cycling: The contrasting experiences of professionals and amateurs

The focus of researchers, media and policy on doping in cycling is often limited to the professional level of the sport. However, anti-doping test results since 2001 demonstrate that banned substances are also used by US cyclists at lower levels of the sport, necessitating a broader view of the patterns and motivations of substance use within the sport. In this article, we describe and explain the doping culture that has emerged in domestic US cycling among amateur and semi-professionals. Through analysis of records from sports governing bodies and journalistic reports, we assess the range of violation types and discuss the detection and punishing of riders who were not proven to have intended to cheat but became "collateral damage" in the war on doping. We argue that the phenomenon of doping is more complex than what has been shown to occur in elite sport, as it includes a wider variety of behaviours, situations and motivations. We develop fresh insights by examining cases where doping has been accidental, intrinsically motivated, non-performance enhancing or the result of prescribed medical treatments banned by anti-doping authorities. Such trends call into question the fairness of anti-doping measures, and we discuss the possibility of developing localised solutions to testing and sanctioning amateur athletes