Bidirectional reflectance capabilities of the NIST Robotic Optical Scattering Instrument.

The National Institute of Standards and Technology (NIST) Robotic Optical Scattering Instrument (ROSI) serves as the national reference instrument for specular and diffuse bidirectional reflectance measurements in the ultraviolet to short-wave infrared wavelength regions. This paper gives a comprehensive overview of the design, operation, and capabilities of ROSI. We describe measurement methods for diffuse and specular reflectance, identify and quantify the elements of the uncertainty budget, and validate the reflectance scale through comparison with NIST's previous reference instrument, the Spectral Tri-function Automated Reference Reflectometer. Examples of the range of ROSI's capabilities, including the limits for low-reflectance measurements and a research application using out-of-plane measurements of bidirectional reflectance for remote sensing reference reflectors, are also covered.

Uncertainty in global downwelling plane irradiance estimates from sintered polytetrafluoroethylene plaque radiance measurements.

Global downwelling plane irradiance is a necessary variable to normalize water-leaving radiance measurements, reducing the magnitude and spectral variabilities introduced by the incident light field. As a result, the normalized measurements, known as remote sensing reflectance, have higher correlation with the inherent optical properties of the water body and so to the composition of optically active water components. For in situ measurements, the global downwelling plane irradiance can be estimated from the exitant radiance of sintered polytetrafluoroethylene plaques or other diffuse reflectance standards. This allows use of a single spectrometer to measure all necessary variables to estimate the remote sensing reflectance, reducing cost in acquisition and maintenance of instrumentation. However, despite being in use for more than 30 years, the uncertainty associated with the method has been only partially evaluated. In this study, we use a suite of sky radiance distributions for 24 atmospheres and nine solar zenith angles in combination with full bidirectional reflectance distribution function determinations of white and gray plaques to evaluate the uncertainties. The isolated and interactive effects of bidirectional reflectance distribution, shadowing, and tilt error sources are evaluated. We find that under the best-performing geometries of each plaque, and with appropriate estimation functions, average standard uncertainty ranges from 1% to 6.5%. The simulated errors are found to explain both previous empirical uncertainty estimates and new data collected during this study. Those errors are of the same magnitude as uncertainties of plane irradiance sensors (e.g., cosine collectors) and overlap with uncertainty requirements for different uses of in situ data, which supports the continued use of the plaque method in hydrologic optics research and monitoring. Recommendations are provided to improve the quality of measurements and assure that uncertainties will be in the range of those calculated here.

"Keep it Realistic": Reactions to and Recommendations for Physical Activity Promotion Messages From Focus Groups of Women.

PURPOSE: Less than half of US adults meet the recommended guidelines of 150 minutes of exercise each week. Health promotion messages are frequently used to promote physical activity (PA); however, this messaging may be ineffective if it does not resonate with the target audience. The purpose of this exploratory study is to understand how women respond to examples of PA promotion messages. APPROACH/DESIGN: A qualitative study. SETTING: Washington DC Metro Area. PARTICIPANTS: Forty women, stratified by race/ethnicity (white, black, Latina) and level of self-reported PA (active, inactive). METHOD: Eight focus groups were conducted in which participants were shown 3 PA promotion messages representative of typical messaging strategies. Three researchers conducted a thematic analysis to code the data for emergent themes. RESULTS: Current PA promotion messaging strategies do not resonate with women. Women want to see individuals with "realistic" bodies who look similar to them (eg, body shape, age, race/ethnicity), and for PA messaging to include daily activities as a way to be active. CONCLUSIONS: Public health practitioners who promote PA to women should consider developing messages that better resonate with women's dynamic roles and lifestyles. Successful strategies may include depicting busy lifestyles that PA may be physically and logistically difficult to fit into and using models with diverse body shapes.

Initial Assessment of a Comprehensive Digital Smoking Cessation Program That Incorporates a Mobile App, Breath Sensor, and Coaching: Cohort Study.

BACKGROUND: Cigarette smoking is the leading cause of preventable morbidity and mortality, excess health care expenditure, and lost work productivity. Otherwise effective evidence-based treatments have had limited success owing to challenges with access, engagement, and scale. Pivot is a comprehensive digital smoking cessation program that incorporates a Food and Drug Administration-cleared carbon monoxide breath sensor, smartphone app, and text-based human coaching. OBJECTIVE: This initial evaluation of Pivot aimed to assess participant engagement, changes in attitudes toward quitting, and changes in smoking behavior. METHODS: US cigarette smokers aged 18 to 65 years who smoked ≥5 cigarettes per day (CPD) were recruited online. Participants completed a screening call, electronic informed consent, registration, and onboarding before beginning Pivot. Pivot includes 5 sequential stages (Explore, Build, Mobilize, Quit, and Secure), taking 14.5 to 18.5 weeks to complete. Data were collected via app and online questionnaires. Outcomes included engagement and retention (ie, weeks of active engagement and Pivot stage progression); attitudes toward quitting (ie, quit readiness, quit confidence, and expected difficulty maintaining quit); and smoking behavior (ie, quit attempts, cigarette reduction, and abstinence (7- and 30-day point prevalence abstinence [PPA]). RESULTS: A total of 319 participants completed onboarding (intention-to-treat [ITT] sample); 272/319 participants (85.3%) completed the end-of-Pivot questionnaire (study completer sample). Most (212/319, 66.5%) were not ready to quit in the next 30 days at baseline. On average, participants actively engaged in the program for a mean 12.4 (SD 7.1) weeks. Pivot stage completion rates were Explore: 88.7% (283/319), Build: 57.4% (183/319), Mobilize: 43.6% (139/319), Quit: 41.1% (131/319), and Secure: 39.5% (126/319). Repeated measures linear mixed model analyses demonstrated positive changes in attitudes from baseline to Mobilize (pre-Quit): increased confidence to quit (4.2 to 7.4, P<.001) and decreased expected difficulty maintaining quit (3.1 to 6.8, P<.001). The quit attempt rate (ie, those making ≥1 quit attempt lasting ≥1 day) was 79.4% (216/272, completer). At the end of Pivot, 7-day PPA rates were 32.0% (102/319, ITT) and 37.5% (102/272, completer); 30-day PPA rates were 27.6% (88/319, ITT) and 32.4% (88/272, completer). Moreover, 30-day PPA rates were comparable among those ready and not ready to quit in the next 30 days at baseline. Of those not achieving abstinence, 25.9% (44/170, completer) achieved ≥50% reduction in CPD by study end. CONCLUSIONS: This study evaluated Pivot's initial performance with comparable quit rates among those ready and not ready to quit in the next 30 days at entry. The present data, considered with the program's accessibility, innovation, evidence-based foundation, and design for all smokers, suggest Pivot has the potential to address limitations of reach and scale and thereby advance smoking cessation efforts. TRIAL REGISTRATION: ClinicalTrials.gov NCT03295643; https://clinicaltrials.gov/ct2/show/NCT03295643 (Archived by WebCite at http://www.webcitation.org/75TiNe6BE).

The Intersection of Behavioral Science and Digital Health: The Case for Academic-Industry Partnerships.

A decade after the first health app became available, the field of digital health has produced a range of health behavior insights and an expanding product portfolio. Despite sustained interest and growth fueled by academic and industry interests, the impact of digital health on health behavior change and related outcomes has been limited. This underperformance relative to expectations may be partially attributed to a gap between industry and academia in which both seek to develop technology-driven solutions but fail to converge around respective, unique strengths. An opportunity exists for new and improved collaborative models of research, innovation, and care delivery that disrupt the field of behavioral medicine and benefit academic and industry interests. For those partnerships to thrive, recognizing key differences between academic and industry roles may help smooth the path. Here we speak specifically to concerns particular to academics and offer suggestions for how to navigate related challenges.

A Comprehensive Digital Program for Smoking Cessation: Assessing Feasibility in a Single-Group Cohort Study.

BACKGROUND: Cigarette smoking remains the leading cause of preventable death and disease worldwide. Evidence-based approaches are available, but few people access them. Although digital solutions offer great promise for population reach, few multicomponent programs exist. Pivot is a comprehensive digital solution combining a Food and Drug Administration-cleared carbon monoxide (CO) breath sensor; cigarette logging; a 6-phase, app-delivered smoking cessation program based on the US Clinical Practice Guidelines; and dedicated human coaching via text-based chat. OBJECTIVE: The purpose of this study was to assess program engagement, changes in attitudes toward smoking, self-reported changes in smoking behavior, and program acceptability for the initial phase of Pivot: Explore. METHODS: A total of 48 participants enrolled, and 41 completed the study. About half the participants (54%, 22/41) were men, and the mean age was 43 years. Most (85%, 35/41) were daily smokers and smoked an average of 12 cigarettes per day. Explore includes CO breath sensing, logging cigarettes in-app, learning via in-app activities, and dedicated human coaching through a text messaging interface. Participants completed surveys at baseline and exit assessing attitudes toward quitting including readiness, perceived difficulty, and confidence in quit success. At exit, participants also completed a survey of changes in smoking behavior and ratings of program acceptability. RESULTS: More than 80% of participants (34-39 of 41) took ≥1 CO breath sample each day, and more than 55% (23-27 of 41) took ≥5 samples each day. More than 65% of participants (27-34 of 41) logged ≥1 cigarette using the in-app logging feature each day. All 9 in-app activities had completion rates ≥80% (33-40 of 41). Response to coach-initiated outreach was also high, with all contacts receiving ≥73% (30-39 of 41) response. In matched pair analyses, significant positive changes in mean attitudes toward quitting (scale 1-10) were evident from baseline (T1) to study exit (T2), including increased readiness to quit (T1 mean=6.1, T2 mean=7.4, P=.005), lower perceived difficulty (T1 mean=3.7, T2 mean=5.6, P=.001), and greater expectations of success (T1 mean=4.5, T2 mean=6.5, P<.001). At exit, 78% (32/41) of participants reported decreasing the number of cigarettes smoked per day during the study. Participants rated program quality and satisfaction very high (mean ≥8 for all items). CONCLUSIONS: These results support the feasibility and acceptability of the initial 9-day phase of Pivot: Explore. Participants had high levels of engagement with sensing, logging, learning, and coaching. Attitudes toward quitting improved significantly, and the majority of users indicated decreasing smoking behavior. Explore was designed to raise smoker awareness and motivation. Additional research is underway to assess how users progress through the full Pivot smoking cessation program and determine the program's effectiveness for achieving sustained cessation.

Rethinking physical activity communication: using focus groups to understand women's goals, values, and beliefs to improve public health.

BACKGROUND: Communication about physical activity (PA) frames PA and influences what it means to people, including the role it plays in their lives. To the extent that PA messages can be designed to reflect outcomes that are relevant to what people most value experiencing and achieving in their daily lives, the more compelling and effective they will be. Aligned with self-determination theory, this study investigated proximal goals and values that are salient in everyday life and how they could be leveraged through new messaging to better support PA participation among women. The present study was designed to examine the nature of women's daily goals and priorities and investigate women's PA beliefs, feelings, and experiences, in order to identify how PA may compete with or facilitate women's daily goals and priorities. Preliminary recommendations are proposed for designing new PA messages that align PA with women's daily goals and desired experiences to better motivate participation. METHODS: Eight focus groups were conducted with White, Black, and Hispanic/Latina women aged 22-49, stratified by amount of self-reported PA (29 low active participants, 11 high active participants). Respondents discussed their goals, values, and daily priorities along with beliefs, feelings about and experiences being physically active. Data were collected, coded, and analyzed using a thematic analysis strategy to identify emergent themes. RESULTS: Many of the goals and values that both low and high active participants discussed as desiring and valuing map on to key principles of self-determination theory. However, the discussions among low active participants suggested that their beliefs, feelings, experiences, and definitions of PA were in conflict with their proximal goals, values, and priorities, also undermining their psychological needs for autonomy, competence, and relatedness. CONCLUSIONS: Findings from this study can be used to inform and evaluate new physical activity communication strategies that leverage more proximal goals, values, and experiences of happiness and success to better motivate PA among ethnically diverse low active women. Specifically, this research suggests a need to address how women's daily goals and desired experiences may undermine PA participation, in addition to framing PA as facilitating rather than competing with their daily priorities and desired leisure-time experiences.

The FLASHE Study: Survey Development, Dyadic Perspectives, and Participant Characteristics.

The National Cancer Institute developed the Family Life, Activity, Sun, Health, and Eating (FLASHE) Study to examine multiple cancer preventive behaviors within parent-adolescent dyads. The purpose of creating FLASHE was to enable the examination of physical activity, diet, and other cancer preventive behaviors and potential correlates among parent-adolescent dyads. FLASHE surveys were developed from a process involving literature reviews, scientific input from experts in the field, cognitive testing, and usability testing. This cross-sectional, web-based study of parents and their adolescent children (aged 12-17 years) was administered between April and October 2014. The nationwide sample consisted of 1,573 parent-adolescent dyads (1,699 parents and 1,581 adolescents) who returned all FLASHE surveys. FLASHE assessed parent and adolescent reports of several intrapersonal and interpersonal domains (including psychosocial variables, parenting, and the community and home environments). On a subset of example FLASHE items across these domains, responses of parents and adolescents within the same dyads were positively and significantly correlated (r =0.32-0.63). Analyses were run in 2015-2016. FLASHE data present multiple opportunities for studying research questions among individuals or dyads, including the ability to examine similarity between parents and adolescents on many constructs relevant to cancer preventive behaviors. FLASHE data are publicly available for researchers and practitioners to help advance research on cancer preventive health behaviors.

Autonomous Motivation and Fruit/Vegetable Intake in Parent-Adolescent Dyads.

INTRODUCTION: Autonomous motivation (motivation to engage in a behavior because of personal choice, interest, or value) is often associated with health behaviors. The present study contributes to research on motivation and eating behaviors by examining (1) how autonomous motivation is correlated within parent-adolescent dyads and (2) whether parent- and adolescent-reported autonomous motivation predicts the parent-adolescent correlation in fruit and vegetable (FV) intake frequency. METHODS: Data were drawn from the Family Life, Activity, Sun, Health, and Eating (FLASHE) Study, a cross-sectional U.S. survey of parent-adolescent dyads led by the National Cancer Institute and fielded between April and October 2014. In 2016, data were analyzed from dyads who had responses on a six-item self-report measure of daily frequency of FV consumption and a two-item self-report measure of autonomous motivation for consuming FVs. RESULTS: Parents' and adolescents' reports of autonomous motivation and FV intake frequency were positively correlated. Both parents' and adolescents' autonomous motivation predicted higher levels of their own FV intake frequency and that of their dyad partner (p-values ≤0.001). These effects of autonomous motivation explained 22.6% of the parent-adolescent correlation in FV intake frequency. Actor effects (one's motivation predicting their own FV intake frequency) were stronger than partner effects (one's motivation predicting their partner's FV intake frequency). CONCLUSIONS: Parent-adolescent similarity in autonomous motivation for healthy eating may contribute to similarity in eating behaviors. Future research should further examine how individual-level health behavior correlates influence health behaviors within dyads.

Stirring the motivational soup: within-person latent profiles of motivation in exercise.

BACKGROUND: The purpose of the present study was to use a person-oriented analytical approach to identify latent motivational profiles, based on the different behavioural regulations for exercise, and to examine differences in satisfaction of basic psychological needs (competence, autonomy and relatedness) and exercise behaviour across these motivational profiles. METHODS: Two samples, consisting of 1084 and 511 adults respectively, completed exercise-related measures of behavioural regulation and psychological need satisfaction as well as exercise behaviour. Latent profile analyses were used to identify motivational profiles. RESULTS: Six profiles, representing different combinations of regulations for exercise, were found to best represent data in both samples. Some profiles were found in both samples (e.g., low motivation profile, self-determined motivation profile and self-determined with high introjected regulation profile), whereas others were unique to each sample. In line with the Self-Determination Theory, individuals belonging to more self-determined profiles demonstrated higher scores on need satisfaction. CONCLUSIONS: The results support the notions of motivation being a multidimensional construct and that people have different, sometimes competing, reasons for engaging in exercise. The benefits of using person-oriented analyses to examine within-person interactions of motivation and different regulations are discussed.

Brief report of virtual clinician research tools for tobacco dependence or dyslipidemia.

Health avatars were created to deliver previously tested live interventions for tobacco dependence and cholesterol management. The exploratory aims were to develop and test whether the avatar can be reliably assessed for autonomy supportiveness using the Health Care Climate Questionnaire and estimate the mean changes in motivation variables and correlate the avatars' autonomy supportiveness with the motivation variables and health outcomes. The avatars were found to be reliably assessed for autonomy supportiveness on the Health Care Climate Questionnaire. Autonomy support was positively correlated with the change in motivations and reduction in low-density lipoprotein. These findings suggest that health avatars may be tested in clinical trials.

Outcomes of the Smoker's Health Project: a pragmatic comparative effectiveness trial of tobacco-dependence interventions based on self-determination theory.

A pragmatic comparative effectiveness trial examined whether extending the duration of a cost-effective, intensive tobacco-dependence intervention designed to support autonomy will facilitate long-term tobacco abstinence. Participants were randomly assigned to one of three tobacco-dependence interventions based on self-determination theory, namely, Intensive Treatment (IT; six contacts over 6 months), Extended Need Support (ENS; eight contacts over 12 months) and Harm Reduction (HR; eight contacts over 12 months with medication use if willing to reduce cigarette use by half). Among participants who completed the interventions, analyses revealed beneficial effects of ENS (15.7 versus 3.8%; χ 2(1) = 6.92, P < 0.01) and HR (13.6 versus 3.8%; χ 2(1) = 5.26, P < 0.05), relative to IT, on 12-month prolonged abstinence from tobacco. Also, analyses revealed beneficial effects of ENS (77.7 versus 43.0%; χ 2(1) = 24.90, P < 0.001) and HR (84.0 versus 43.0%; χ 2(1) = 37.41, P < 0.001), relative to IT, on use of first-line medications for smoking cessation. Hence, two new interventions were found to be efficacious particularly among participants who completed the interventions. Smokers who stay in treatment for an additional 6 months may benefit from an additional two contacts with practitioners, and thus it seems reasonable for policy makers to offer additional contacts given the health benefits associated with prolonged tobacco abstinence.

Baseline Motivation Type as a Predictor of Dropout in a Healthy Eating Text Messaging Program.

BACKGROUND: Growing evidence suggests that text messaging programs are effective in facilitating health behavior change. However, high dropout rates limit the potential effectiveness of these programs. OBJECTIVE: This paper describes patterns of early dropout in the HealthyYou text (HYTxt) program, with a focus on the impact of baseline motivation quality on dropout, as characterized by Self-Determination Theory (SDT). METHODS: This analysis included 193 users of HYTxt, a diet and physical activity text messaging intervention developed by the US National Cancer Institute. Descriptive statistics were computed, and logistic regression models were run to examine the association between baseline motivation type and early program dropout. RESULTS: Overall, 43.0% (83/193) of users dropped out of the program; of these, 65.1% (54/83; 28.0% of all users) did so within the first 2 weeks. Users with higher autonomous motivation had significantly lower odds of dropping out within the first 2 weeks. A one unit increase in autonomous motivation was associated with lower odds (odds ratio 0.44, 95% CI 0.24-0.81) of early dropout, which persisted after adjusting for level of controlled motivation. CONCLUSIONS: Applying SDT-based strategies to enhance autonomous motivation might reduce early dropout rates, which can improve program exposure and effectiveness.

Social Network Behavior and Engagement Within a Smoking Cessation Facebook Page.

BACKGROUND: Social media platforms are increasingly being used to support individuals in behavior change attempts, including smoking cessation. Examining the interactions of participants in health-related social media groups can help inform our understanding of how these groups can best be leveraged to facilitate behavior change. OBJECTIVE: The aim of this study was to analyze patterns of participation, self-reported smoking cessation length, and interactions within the National Cancer Institutes' Facebook community for smoking cessation support. METHODS: Our sample consisted of approximately 4243 individuals who interacted (eg, posted, commented) on the public Smokefree Women Facebook page during the time of data collection. In Phase 1, social network visualizations and centrality measures were used to evaluate network structure and engagement. In Phase 2, an inductive, thematic qualitative content analysis was conducted with a subsample of 500 individuals, and correlational analysis was used to determine how participant engagement was associated with self-reported session length. RESULTS: Between February 2013 and March 2014, there were 875 posts and 4088 comments from approximately 4243 participants. Social network visualizations revealed the moderator's role in keeping the community together and distributing the most active participants. Correlation analyses suggest that engagement in the network was significantly inversely associated with cessation status (Spearman correlation coefficient = -0.14, P=.03, N=243). The content analysis of 1698 posts from 500 randomly selected participants identified the most frequent interactions in the community as providing support (43%, n=721) and announcing number of days smoke free (41%, n=689). CONCLUSIONS: These findings highlight the importance of the moderator for network engagement and provide helpful insights into the patterns and types of interactions participants are engaging in. This study adds knowledge of how the social network of a smoking cessation community behaves within the confines of a Facebook group.

Optical reflectance of pyrheliometer absorption cavities: progress toward SI-traceable measurements of solar irradiance.

We have accurately determined the absorptance of three pyrheliometer cavities at 532 nm by measuring the residual reflectance using an angle-resolved bidirectional reflectometer. Measurements were performed at a normal incidence as a function of the viewing angle and position on the cavity cone. By numerically integrating the measured angle-resolved scatter over both the direction and position and accounting for an obstructed view of the cavity, we determined that the effective cavity reflectance was between 8×10-4 and 9×10-4. Thus, the absorptance of the three cavities ranged from 0.99909±0.00014 to 0.99922±0.00012 (k=2 combined expanded uncertainties). These measurements, when extended over the spectral range of operation of the pyrheliometer, are required to establish SI traceability for absolute solar irradiance measurements.

Correlates of Reported Use and Perceived Helpfulness of Calorie Information in Restaurants Among U.S. Adults.

PURPOSE: This study reports correlates in reported use and helpfulness of calorie information, when available, in restaurants on a national scale in the United States for demographic behavioral and health-related conditions. DESIGN: This study is a secondary data analysis of the 2013 National Cancer Institute's Health Information National Trends Survey data. SETTING: United States. SUBJECTS: Adults (n = 3407). MEASURES: Menu labeling use and helpfulness; behavior change attempts; reported fruit, vegetable, and soda consumption; weight status; and chronic health conditions. ANALYSIS: Trends were identified in weighted logistic and linear regression models. RESULTS: U.S. adults who intended to lose weight (odds ratio [OR] = 5.01 [95% confidence interval 2.96, 8.46]), increase fruit (OR = 1.10 [.66, 1.84]) or vegetable consumption (OR = 2.25 [1.32, 3.83]), or reduce soda consumption (OR = 1.67 [1.11, 2.51]) were more likely to report using menu-labeling information when available. More women reported calorie information was helpful when ordering (p < .05). Racial/ethnic and socioeconomic status disparities were identified in use (non-Hispanic [NH] blacks vs. NH whites OR = .43 [.25, .74]) and helpfulness (NH blacks vs. NH whites ß = -.06 [-.44, .32]). CONCLUSION: Findings highlight potential subgroups to target for communication and education efforts regarding use of calorie information in restaurants. Following publication of final rules for federal menu-labeling legislation and implementation, further surveillance of public response to this information may inform message framing and educational interventions to promote use of calorie information on menu boards.

A Pilot Test of Self-Affirmations to Promote Smoking Cessation in a National Smoking Cessation Text Messaging Program.

BACKGROUND: Although effective smoking cessation treatments, including mHealth interventions, have been empirically validated and are widely available, smoking relapse is likely. Self-affirmation, a process through which individuals focus on their strengths and behaviors, has been shown to reduce negative effects of self-threats and to promote engagement in healthier behavior. OBJECTIVE: To assess the feasibility of incorporating self-affirmations into an existing text messaging-based smoking cessation program (Smokefree TXT) and to determine whether self-affirmation led to greater engagement and higher cessation rates than the standard intervention. METHODS: Data were collected from smokers (n=1261) who subscribed to a free smoking cessation program and met eligibility criteria. The intervention lasted 42 days. The original design was a 2 (Baseline affirmation: 5-item questionnaire present vs absent) × 2 (Integrated affirmation: texts present vs absent) factorial design. Only 17 eligible users completed all baseline affirmation questions and these conditions did not influence any outcomes, so we collapsed across baseline affirmation conditions in analysis. In the integrated affirmation conditions, affirmations replaced approximately 20% of texts delivering motivational content. RESULTS: In all, 687 users remained enrolled throughout the 42-day intervention and 81 reported smoking status at day 42. Among initiators (n=1261), self-affirmation did not significantly improve (1) intervention completion, (2) days enrolled, (3) 1-week smoking status, or (4) 6-week smoking status (all Ps>.10); and among the 687 completers, there were no significant effects of affirmation on cessation (Ps>.25). However, among the 81 responders, those who received affirmations were more likely to report cessation at 6 weeks (97.5%; 39 of 40) than those not given affirmations (78.1%; 32 of 41; χ(2)(1)=7.08, P=.008). CONCLUSION: This proof-of-concept study provides preliminary evidence that self-affirmation can be integrated into existing text-based cessation programs, as the affirmations did not lead to any adverse effects (ie, less engagement or lower rates of cessation). Among those who reported smoking status at the end of the intervention period (6.4% of eligible respondents), affirmations facilitated cessation. This study provides a "proof-of-concept" that brief, low-touch interventions may be integrated into a text messaging program with potential benefits, minimal disruption to the program or users, and little cost. Many questions remain regarding how self-affirmation and similar approaches can promote engagement in population interventions.

There Are Thousands of Apps for That: Navigating Mobile Technology for Nutrition Education and Behavior.

Mobile health (mHealth) is an emerging field devoted to the use of mobile and wireless devices to affect health outcomes, health care services, and health research. Despite great promise, little research has examined its effectiveness. It is the authors' view that the full potential of mHealth has yet to be realized in research and practice. This Perspective article explores when and for whom mHealth approaches are effective, strengths and limitations of commercially and academically generated apps, research design considerations, and public-private partnerships. These topics have implications for researchers and practitioners who wish to advance the science and practice of mHealth.

Fundamental constructs in food parenting practices: a content map to guide future research.

Although research shows that "food parenting practices" can impact children's diet and eating habits, current understanding of the impact of specific practices has been limited by inconsistencies in terminology and definitions. This article represents a critical appraisal of food parenting practices, including clear terminology and definitions, by a working group of content experts. The result of this effort was the development of a content map for future research that presents 3 overarching, higher-order food parenting constructs--coercive control, structure, and autonomy support--as well as specific practice subconstructs. Coercive control includes restriction, pressure to eat, threats and bribes, and using food to control negative emotions. Structure includes rules and limits, limited/guided choices, monitoring, meal- and snacktime routines, modeling, food availability and accessibility, food preparation, and unstructured practices. Autonomy support includes nutrition education, child involvement, encouragement, praise, reasoning, and negotiation. Literature on each construct is reviewed, and directions for future research are offered. Clear terminology and definitions should facilitate cross-study comparisons and minimize conflicting findings resulting from previous discrepancies in construct operationalization.

Goniometric and hemispherical reflectance and transmittance measurements of fused silica diffusers.

Fused silica diffusers, made by forming scattering centers inside fused silica glass, can exhibit desirable optical properties, such as reflectance or transmittance independent of viewing angle, spectrally flat response into the ultraviolet wavelength range, and good spatial uniformity. The diffusers are of interest for terrestrial and space borne remote sensing instruments, which use light diffusers in reflective and transmissive applications. In this work, we report exploratory measurements of two samples of fused silica diffusers. We will present goniometric bidirectional scattering distribution function (BSDF) measurements under normal illumination provided by the National Institute of Standards and Technology (NIST)'s Goniometric Optical Scatter Instrument (GOSI), by NIST's Infrared reference integrating sphere (IRIS) and by the National Aeronautics and Space Administration (NASA)'s Diffuser Calibration Laboratory. We also present hemispherical diffuse transmittance and reflectance measurements provided by NIST's Double integrating sphere Optical Scattering Instrument (DOSI). The data from the DOSI is analyzed by Prahl's inverse adding-doubling algorithm to obtain the absorption and reduced scattering coefficient of the samples. Implications of fused silica diffusers for remote sensing applications are discussed.