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The Southern Ocean upper-layer freshwater balance exerts a global climatic influence by modulating density stratification and biological productivity, and hence the exchange of heat and carbon between the atmosphere and the ocean interior. It is thus important to understand and quantify the time-varying freshwater inputs, which is challenging from measurements of salinity alone. Here we use seawater oxygen isotopes from samples collected between 2016 and 2021 along a transect spanning the Scotia and northern Weddell Seas to separate the freshwater contributions from sea ice and meteoric sources. The unprecedented retreat of sea ice in 2016 is evidenced as a strong increase in sea ice melt across the northern Weddell Sea, with surface values increasing approximately two percentage points between 2016 and 2018 and column inventories increasing approximately 1 to 2 m. Surface meteoric water concentrations exceeded 4% in early 2021 close to South Georgia due to meltwater from the A68 megaberg; smaller icebergs may influence meteoric water at other times also. Both these inputs highlight the importance of a changing cryosphere for upper-ocean freshening; potential future sea ice retreats and increases in iceberg calving would enhance the impacts of these freshwater sources on the ocean and climate. This article is part of a discussion meeting issue ‘Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities’.

The synaptic event called the inhibitory junction potential (IJP) was arguably one of the more important discoveries made by Burnstock and arguably one of his finer legacies. The discovery of the IJP fundamentally changed how electromechanical coupling was visualised in gastrointestinal smooth muscle. Its discovery also set in motion the search for novel inhibitory neurotransmitters in the enteric nervous system, eventually leading to proposal that ATP or a related nucleotide was a major inhibitory transmitter. The subsequent development of purinergic signalling gave impetus to expanding the classification of surface receptors for extracellular ATP, not only in the GI tract but beyond, and then led to successive phases of medicinal chemistry as the P2 receptor field developed. Ultimately, the discovery of the IJP led to the successful cloning of the first P2Y receptor (chick P2Y1) and expansion of mammalian ATP receptors into two classes: metabotropic P2Y receptors (encompassing P2Y1, P2Y2, P2Y4, P2Y6, P2Y11–14 receptors) and ionotropic P2X receptors (encompassing homomeric P2X1–P2X7 receptors). Here, the causal relationship between the IJP and P2Y1 is explored, setting out the milestones reached and achievements made by Burnstock and his colleagues.

Raising the minimum legal sales age (MLSA) for tobacco products to 21 years (T21) is a strategy to help prevent and delay the initiation of tobacco product use (1). On December 20, 2019, Congress raised the federal MLSA for tobacco products from 18 to 21 years. Before enactment of the federal T21 law, localities, states, and territories were increasingly adopting their own T21 laws as part of a comprehensive approach to prevent youth initiation of tobacco products, particularly in response to recent increases in use of e-cigarettes among youths (2). Nearly all tobacco product use begins during adolescence, and minors have cited social sources such as older peers and siblings as a common source of access to tobacco products (1,3). State and territorial T21 laws vary widely and can include provisions that might not benefit the public's health, including penalties to youths for purchase, use, or possession of tobacco products; exemptions for military populations; phase-in periods; and preemption of local laws. To understand the landscape of U.S. state and territorial T21 laws before enactment of the federal law, CDC assessed state and territorial laws prohibiting sales of all tobacco products to persons aged

The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15539. Ion channels are one of the six major pharmacological targets into which the Guide is divided, with the others being: G protein-coupled receptors, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate. ispartof: BRITISH JOURNAL OF PHARMACOLOGY vol:178 pages:S157-S245 ispartof: location:England status: published

Chlorophyll has long been known to influence air–sea gas exchange and CO2 drawdown. But chlorophyll also influences regional climate through its effect on solar radiation absorption and thus sea surface temperature (SST). In the Bay of Bengal, the effect of chlorophyll on SST has been demonstrated to have a significant impact on the Indian summer (southwest) monsoon. However, little is known about the drivers and impacts of chlorophyll variability in the Bay of Bengal during the southwest monsoon. Here we use observations of downwelling irradiance measured by an ocean glider and three profiling floats to determine the spatial and temporal variability of solar absorption across the southern Bay of Bengal during the 2016 summer monsoon. A two-band exponential solar absorption scheme is fitted to vertical profiles of photosynthetically active radiation to determine the effective scale depth of blue light. Scale depths of blue light are found to vary from 12 m during the highest (0.3–0.5 mg m−3) mixed-layer chlorophyll concentrations to over 25 m when the mixed-layer chlorophyll concentrations are below 0.1 mg m−3. The Southwest Monsoon Current and coastal regions of the Bay of Bengal are observed to have higher mixed-layer chlorophyll concentrations and shallower solar penetration depths than other regions of the southern Bay of Bengal. Substantial sub-daily variability in solar radiation absorption is observed, which highlights the importance of near-surface ocean processes in modulating mixed-layer chlorophyll. Simulations using a one-dimensional K-profile parameterization ocean mixed-layer model with observed surface forcing from July 2016 show that a 0.3 mg m−3 increase in chlorophyll concentration increases sea surface temperature by 0.35 ∘C in 1 month, with SST differences growing rapidly during calm and sunny conditions. This has the potential to influence monsoon rainfall around the Bay of Bengal and its intraseasonal variability.

Chlorophyll influences regional climate through its effect on solar radiation absorption and thus sea surface temperature (SST). In the Bay of Bengal, the effect of chlorophyll on SST has been demonstrated to have a significant impact on the Indian summer (southwest) monsoon. However, little is known about the drivers and impacts of chlorophyll variability in the Bay of Bengal during the southwest monsoon. Here we use observations of downwelling irradiance measured by an ocean glider and three profiling floats to determine the spatial and temporal variability of solar absorption across the southern Bay of Bengal during the 2016 summer monsoon. A two-band exponential solar absorption scheme is fitted to vertical profiles of photosynthetically active radiation to determine the effective scale depth of blue light. Scale depths of blue light are found to vary from 12 m during the highest (0.3–0.5 mg m−3) mixed layer chlorophyll concentrations, to over 25 m when the mixed layer chlorophyll concentrations are below 0.1 mg m−3. The Southwest Monsoon Current and coastal regions of the Bay of Bengal are observed to have higher mixed layer chlorophyll concentrations and shallower solar penetration depths than other regions of the southern Bay of Bengal. Substantial sub-daily variability in solar radiadion absorption is observed, which highlights the importance of near-surface ocean processes in modulating mixed layer chlorophyll. Simulations using a one-dimensional K-profile parameterisation ocean mixed layer model with observed surface forcing from July 2016 show that a 0.3 mg m−3 increase in chlorophyll concentration increases sea surface temperature by 0.35 °C in one month with SST differences growing rapidly during calm and sunny conditions. This has the potential to influence monsoon rainfall around the Bay of Bengal and its intraseasonal variability.

Objectives Social media use is associated with developing communities of practice that promote the rapid exchange of information across traditional institutional and geographical boundaries faster than previously possible. We aimed to describe and share our experience using #neoEBM (Neonatal Evidence Based Medicine) hashtag to organise and build a digital community of neonatal care practice. Materials and methods Analysis of #neoEBM Twitter data in the Symplur Signals database between 1 May 2018 to 9 January 2021. Data on tweets containing the #neoEBM hashtag were analysed using online analytical tools, including the total number of tweets and user engagement. Results Since its registration, a total of 3 228 distinct individual Twitter users used the hashtag with 23 939 tweets and 37 259 710 impressions generated. The two days with the greatest number of tweets containing #neoEBM were 8 May 2018 (n = 218) and 28 April 2019 (n = 340), coinciding with the annual Pediatric Academic Societies meeting. The majority of Twitter users made one tweet using #neoEBM (n = 1078), followed by two tweets (n = 411) and more than 10 tweets (n = 347). The number of individual impressions (views) of tweets containing #neoEBM was 37 259 710. Of the 23 939 tweets using #neoEBM, 17 817 (74%) were retweeted (shared), 15 643 (65%) included at least one link and 1 196 (5%) had at least one reply. As #neoEBM users increased over time, so did tweets containing #neoEBM, with each additional user of the hashtag associated with a mean increase in 7.8 (95% CI 7.7–8.0) tweets containing #neoEBM. Conclusion Our findings support the observation that the #neoEBM community possesses many of the characteristics of a community of practice, and it may be an effective tool to disseminate research findings. By sharing our experiences, we hope to encourage others to engage with or build online digital communities of practice to share knowledge and build collaborative networks across disciplines, institutions and countries.

The use of any tobacco product by youths is unsafe, including electronic cigarettes (e-cigarettes) (1). Most e-cigarettes contain nicotine, which is highly addictive, can harm the developing adolescent brain, and can increase risk for future addiction to other drugs (1). E-cigarette use has increased considerably among U.S. youths since 2011 (1,2). Multiple factors have contributed to this increase, including youth-appealing flavors and product innovations (1-3). Amid the widespread use of e-cigarettes and popularity of certain products among youths, on February 6, 2020, the Food and Drug Administration (FDA) implemented a policy prioritizing enforcement against the manufacture, distribution, and sale of certain unauthorized flavored prefilled pod or cartridge-based e-cigarettes (excluding tobacco or menthol).

Background Qualitatively atypical language development characterized by non-sequential skill acquisition within a developmental domain, which has been called developmental deviance or difference, is a common characteristic of autism spectrum disorder (ASD). We developed the Response Dispersion Index (RDI), a measure of this phenomenon based on intra-subtest scatter of item responses on standardized psychometric assessments, to assess the within-task variability among individuals with language impairment (LI) and/or ASD. Methods Standard clinical assessments of language were administered to 502 individuals from the New Jersey Language and Autism Genetics Study (NJLAGS) cohort. Participants were divided into four diagnostic groups: unaffected, ASD-only, LI-only, and ASD + LI. For each language measure, RDI was defined as the product of the total number of test items and the sum of the weight (based on item difficulty) of test items missed. Group differences in RDI were assessed, and the relationship between RDI and ASD diagnosis among individuals with LI was investigated for each language assessment. Results Although standard scores were unable to distinguish the LI-only and ASD/ASD + LI groups, the ASD/ASD + LI groups had higher RDI scores compared to LI-only group across all measures of expressive, pragmatic, and metalinguistic language. RDI was positively correlated with quantitative ASD traits across all subgroups and was an effective predictor of ASD diagnosis among individuals with LI. Conclusions The RDI is an effective quantitative metric of developmental deviance/difference that correlates with ASD traits, supporting previous associations between ASD and non-sequential skill acquisition. The RDI can be adapted to other clinical measures to investigate the degree of difference that is not captured by standard performance summary scores.

Introduction Since 2012, the Centers for Disease Control and Prevention has conducted the national Tips From Former Smokers® public education campaign, which motivates smokers to quit by featuring people living with the real-life health consequences of smoking. Cost effectiveness, from the healthcare sector perspective, of the Tips From Former Smokers® campaign was compared over 2012–2018 with that of no campaign. Methods A combination of survey data from a nationally representative sample of U.S. adults that includes cigarette smokers and literature-based lifetime relapse rates were used to calculate the cumulative number of Tips From Former Smokers® campaign‒associated lifetime quits during 2012–2018. Then, lifetime health benefits (premature deaths averted, life years saved, and quality-adjusted life years gained) and healthcare sector cost savings associated with these quits were assessed. All the costs were adjusted for inflation in 2018 U.S. dollars. The Tips From Former Smokers® campaign was conducted and the survey data were collected during 2012–2018. Analyses were conducted in 2019. Results During 2012–2018, the Tips From Former Smokers® campaign was associated with an estimated 129,100 premature deaths avoided, 803,800 life years gained, 1.38 million quality-adjusted life years gained, and $7.3 billion in healthcare sector cost savings on the basis of an estimated 642,200 campaign-associated lifetime quits. The Tips From Former Smokers® campaign was associated with cost savings per lifetime quit of $11,400, per life year gained of $9,100, per premature deaths avoided of $56,800, and per quality-adjusted life year gained of $5,300. Conclusions Mass-reach health education campaigns, such as Tips From Former Smokers®, can help smokers quit, improve health outcomes, and potentially reduce healthcare sector costs.

The known seven mammalian receptor subunits (P2X1-7) form cationic channels gated by ATP. Three subunits compose a receptor channel. Each subunit is a polypeptide consisting of two transmembrane regions (TM1 and TM2), intracellular N- and C-termini, and a bulky extracellular loop. Crystallization allowed the identification of the 3D structure and gating cycle of P2X receptors. The agonist-binding pocket is located at the intersection of two neighbouring subunits. In addition to the mammalian P2X receptors, their primitive ligand-gated counterparts with little structural similarity have also been cloned. Selective agonists for P2X receptor subtypes are not available, but medicinal chemistry supplied a range of subtype-selective antagonists, as well as positive and negative allosteric modulators. Knockout mice and selective antagonists helped to identify pathological functions due to defective P2X receptors, such as male infertility (P2X1), hearing loss (P2X2), pain/cough (P2X3), neuropathic pain (P2X4), inflammatory bone loss (P2X5), and faulty immune reactions (P2X7).

A dynamically passive inert tracer was released in the interior South Pacific Ocean at latitudes of the Antarctic Circumpolar Current. Observational cross sections of the tracer were taken over 4 consecutive years as it drifted through Drake Passage and into the Atlantic Ocean. The tracer was released within a region of high salinity relative to surrounding waters at the same density. In the absence of irreversible mixing a tracer remains at constant salinity and temperature on an isopycnal surface. To investigate the process of irreversible mixing we analysed the tracer in potential density-versus-salinity-anomaly coordinates. Observations of high tracer concentration tended to be collocated with isopycnal salinity anomalies. With time, an initially narrow peak in tracer concentration as a function of salinity at constant density broadened with the tracer being found at ever fresher salinities, consistent with diffusion-like behaviour in that coordinate system. The second moment of the tracer as a function of salinity suggested an initial period of slow spreading for approximately 2 years in the Pacific, followed by more rapid spreading as the tracer entered Drake Passage and the Scotia Sea. Analysis of isopycnal salinity gradients based on the Argo programme suggests that part of this apparent change can be explained by changes in background salinity gradients while part may be explained by the evolution of the tracer patch from a slowly growing phase where the tracer forms filaments to a more rapid phase where the tracer mixes at 240–550 m2 s−1.

Tobacco use is the leading cause of preventable disease and death in the United States, resulting in more than 480,000 premature deaths and $289 billion in direct health care expenditures and productivity losses each year. Despite progress over the past several decades, millions of adults still smoke cigarettes, the most commonly used tobacco product in the United States. To assess progress made toward the Healthy People 2020 target of reducing the proportion of U.S. adults who smoke cigarettes to ≤12.0% (objective TU-1.1), CDC used data from the 2013 National Health Interview Survey (NHIS) to provide updated national estimates of cigarette smoking prevalence among adults aged ≥18 years. Additionally, for the first time, estimates of cigarette smoking prevalence were assessed among lesbian, gay, or bisexual persons (LGB) using NHIS data. The proportion of U.S. adults who smoke cigarettes declined from 20.9% in 2005 to 17.8% in 2013, and the proportion of daily smokers declined from 16.9% to 13.7%. Among daily cigarette smokers, the proportion who smoked 20-29 cigarettes per day (CPD) declined from 34.9% to 29.3%, and the proportion who smoked ≥30 CPD declined from 12.7% to 7.1%. However, cigarette smoking remains particularly high among certain groups, including adults who are male, younger, multiracial or American Indian/Alaska Native, have less education, live below the federal poverty level, live in the South or Midwest, have a disability/limitation, or who are LGB. Proven population-based interventions, including tobacco price increases, comprehensive smoke-free policies in worksites and public places, high-impact anti-tobacco mass media campaigns, and easy access to smoking cessation assistance, are critical to reducing cigarette smoking and smoking-related disease and death among U.S. adults, particularly among subpopulations with the greatest burden.

Exposure to secondhand smoke from burning tobacco products causes premature death and disease, including coronary heart disease, stroke, and lung cancer among nonsmoking adults and sudden infant death syndrome, acute respiratory infections, middle ear disease, exacerbated asthma, respiratory symptoms, and decreased lung function in children (1,2). The U.S. Surgeon General has concluded that there is no risk-free level of exposure to secondhand smoke (1). Previous CDC reports on airport smoke-free policies found that most large-hub airports in the United States prohibit smoking (3); however, the extent of smoke-free policies at airports globally has not been assessed. CDC assessed smoke-free policies at the world's 50 busiest airports (airports with the highest number of passengers traveling through an airport in a year) as of August 2017; approximately 2.7 billion travelers pass through these 50 airports each year (4). Among these airports, 23 (46%) completely prohibit smoking indoors, including five of the 10 busiest airports. The remaining 27 airports continue to allow smoking in designated smoking areas. Designated or ventilated smoking areas can cause involuntary secondhand smoke exposure among nonsmoking travelers and airport employees. Smoke-free policies at the national, city, or airport authority levels can protect employees and travelers from secondhand smoke inside airports.

The lower limb of the Atlantic overturning circulation is resupplied by the sinking of dense Antarctic Bottom Water (AABW) that forms via intense air–sea–ice interactions next to Antarctica, especially in the Weddell Sea1. In the last three decades, AABW has warmed, freshened and declined in volume across the Atlantic Ocean and elsewhere2–7, suggesting an ongoing major reorganization of oceanic overturning8,9. However, the future contributions of AABW to the Atlantic overturning circulation are unclear. Here, using observations of AABW in the Scotia Sea, the most direct pathway from the Weddell Sea to the Atlantic Ocean, we show a recent cessation in the decline of the AABW supply to the Atlantic overturning circulation. The strongest decline was observed in the volume of the densest layers in the AABW throughflow from the early 1990s to 2014; since then, it has stabilized and partially recovered. We link these changes to variability in the densest classes of abyssal waters upstream. Our findings indicate that the previously observed decline in the supply of dense water to the Atlantic Ocean abyss may be stabilizing or reversing and thus call for a reassessment of Antarctic influences on overturning circulation, sea level, planetary-scale heat distribution and global climate2,3,8.

The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. Argo provides continuous observations of ocean temperature and salinity versus pressure, from the sea surface to 2000 dbar. The successful installation of the Argo array and its innovative data management system arose opportunistically from the combination of great scientific need and technological innovation. Through the data system, Argo provides fundamental physical observations with broad societally-valuable applications, built on the cost-efficient and robust technologies of autonomous profiling floats. Following recent advances in platform and sensor technologies, even greater opportunity exists now than 20 years ago to (i) improve Argo’s global coverage and value beyond the original design, (ii) extend Argo to span the full ocean depth, (iii) add biogeochemical sensors for improved understanding of oceanic cycles of carbon, nutrients, and ecosystems, and (iv) consider experimental sensors that might be included in the future, for example to document the spatial and temporal patterns of ocean mixing. For Core Argo and each of these enhancements, the past, present, and future progression along a path from experimental deployments to regional pilot arrays to global implementation is described. The objective is to create a fully global, top-to-bottom, dynamically complete, and multidisciplinary Argo Program that will integrate seamlessly with satellite and with other in situ elements of the Global Ocean Observing System (Legler et al., 2015). The integrated system will deliver operational reanalysis and forecasting capability, and assessment of the state and variability of the climate system with respect to physical, biogeochemical, and ecosystems parameters. It will enable basic research of unprecedented breadth and magnitude, and a wealth of ocean-education and outreach opportunities., Sí

Introduction The long-term health effects of e-cigarettes are uncertain, and data on e-cigarette use among Chinese adults are limited. This study examined the prevalence and correlates of e-cigarette awareness and use among urban residents in China. Data came from the China City Adult Tobacco Survey (CCATS), a city-representative household survey conducted using electronic tablets during 2013-2014 in 14 major Chinese cities. Methods CCATS used multistage geographically clustered samples with standardized survey protocols and questionnaire to ensure data comparability. Overall, 31151 adults completed the survey, with sample size varying from 1977 to 3838 across cities, and survey response rates ranging from 79.8% to 97.5%. Respondents were considered current e-cigarette users if they self-reported using e-cigarettes 'daily' or 'less than daily' at the time of the survey. Descriptive statistics and multivariate logistic regression were conducted. Assessed correlates included: age, education, quit attempts in past 12 months, cigarettes smoked per day, and monthly expenditures on cigarettes. Results Overall, 46.7% of respondents were aware of e-cigarettes, 2.9% ever used, and 0.8% currently used. Most current e-cigarette users (93.0%) also currently smoked tobacco. Among male current tobacco smokers, adjusted odds ratio (AOR) of current e-cigarette use was higher among those aged 15-29 (AOR=2.5; 95% CI: 1.5-4.3) or 30-49 (AOR=1.9; 95% CI: 1.0-3.4) than those ≥50 years; those who attempted to quit in the past 12 months than those who did not (AOR=4.7; 95% CI: 2.2-10.1); those with a college degree (AOR=3.4; 95% CI: 1.9-6.2) or just finished high school (AOR=2.2; 95% CI: 1.2-4.2) than those who did not finish high school; and those who smoked ≥15 cigarettes per day (AOR=2.8; 95% CI: 1.4-5.6) than those who smoked fewer. Conclusions These findings reveal that during 2013-2014, many urban Chinese adults were aware of e-cigarettes, while use was relatively low and most current users also smoked tobacco. Continued monitoring of e-cigarettes could help inform public health policy, planning, and practice.

We construct a novel framework to investigate the uncertainties and biases associated with estimates of deep ocean temperature change from hydrographic sections, and demonstrate this framework in an eddy‐permitting ocean model. Biases in estimates from observations arise due to sparse spatial coverage (few sections in a basin), low frequency of occupations (typically 5‐10 years apart), mismatches between the time period of interest and span of occupations, and from seasonal biases relating to the practicalities of sampling during certain times of year. Between the years 1990 and 2010, the modeled global abyssal ocean biases are small, although regionally some biases (expressed as a heat flux into the 4000 ‐ 6000 m layer) can be up to 0.05 W m−2. In this model, biases in the heat flux into the deep 2000 ‐ 4000 m layer, due to either temporal or spatial sampling uncertainties, are typically much larger and can be over 0.1 W m−2 across an ocean. Overall, 82% of the warming trend deeper than 2000 m is captured by hydrographic section‐style sampling in the model. At 2000 m, only half the model global warming trend is obtained from observational‐style sampling, with large biases in the Atlantic, Southern and Indian Oceans. Biases due to different sources of uncertainty can have opposing signs and differ in relative importance both regionally and with depth, revealing the importance of reducing temporal and spatial uncertainties in future deep ocean observing design. Plain Language Summary In recent decades, deep (below 2000 m) ocean temperature trends have been measured when scientific research vessels repeat the same lines across an ocean basin. Repeats typically happen once or twice a decade and there are only a few repeated lines across each basin. The sparsity of data in both space and time will result in errors in the multidecadal temperature trends calculated from this data. Here, we use a state‐of‐the‐art ocean model to show how trends calculated from observational‐style sampling compare to trends calculated using all model data. For the period 1990‐2010, we estimate the error that may exist in observed deep ocean trend estimates. Overall, around 80% of the below 2000 m warming trend was captured by observational‐style sampling in the model, so deep ocean warming in recent decades may have been underestimated. However, our results are based on only one model simulation. The largest sources of sampling error are found in the Atlantic, Southern and Indian Oceans. For each basin, we reveal whether limited sampling in time or space contributes most error to the temperature trend estimate, and therefore in which regions temperature trend estimates would benefit from additional deep ocean sampling.

Estuaries provide important environmental, social, cultural, and economic services. The provision of these services is often negatively impacted by urban development within the catchment and along shorelines, most notably through habitat loss and alteration of hydrological and sedimentation regimes influencing system structure and function. Mitigating the effects of urban development on estuaries provides a great challenge for managers, particularly when considering the diversity of estuaries and catchment characteristics. The management of urban stormwater is a challenging issue where no single solution is apparent but requires varied approaches. Using three distinctly different Australian estuaries, this chapter presents an account of combined management plans, restoration, monitoring/research, and education efforts used in addressing and managing the issues of urban pressures on water quality surrounding Port Jackson, Gold Coast Broadwater, and the Ross River estuary. Although the case study estuaries significantly vary according to rainfall seasonality and intensity, population density, and catchment size, a survey of implemented protection and management initiatives, illustrates a consistent theme of management practices across the case studies: (1) catchment/estuary management policies and plans including stormwater quality improvement device initiative practices; (2) low impact and purpose-designed development options including water-sensitive urban design options, including specific design adaptations required for effective operation in varying climatic zones and catchment conditions; (3) restoration programs; (4) water quality monitoring programs; (5) research activities; and (6) stakeholder and community education campaigns. The best management outcomes for urbanized estuaries require implementation of catchment-based management plans that are supported by clear objectives regarding ecosystem services and regional challenges.

Introduction The U.S. Surgeon General has concluded that aerosol from electronic vapor products, such as e-cigarettes, can contain harmful and potentially harmful constituents. This study assessed the prevalence and determinants of U.S. adult attitudes toward electronic vapor product use in indoor public places. Methods Data from 2017 Summer Styles, an Internet survey of U.S. adults aged ≥18 years (n = 4,107) were analyzed in 2017. Respondents were asked, Do you favor or oppose allowing the use of electronic vapor products in indoor public places such as workplaces, restaurants, and bars? Responses were strongly favor, somewhat favor, somewhat oppose, and strongly oppose. Multivariate Poisson regression was used to determine sociodemographic correlates of opposition (somewhat or strongly). Results In 2017, a total of 82.4% of adults strongly or somewhat opposed the use of electronic vapor products in indoor public places, including 28.0% of current (past 30-day) electronic vapor product users and 52.7% of current cigarette smokers. After adjustment, opposition was significantly lower among current and former electronic vapor product users than never users, current cigarette smokers than never smokers, and people living with tobacco product users. Opposition was significantly higher among adults aged ≥45 years than those aged 18–24 years and among adults who had rules prohibiting electronic vapor product use in their vehicles or homes than those without such rules. Conclusions Approximately eight in ten U.S. adults, including more than one quarter of electronic vapor product users, opposed electronic vapor product use in indoor public places. Prohibiting electronic vapor product use in indoor public areas can protect bystanders from the health risks of secondhand electronic vapor product aerosol exposure.

The Atlantic Meridional Overturning Circulation (AMOC) is a key component of the global climate system through its transport of heat and freshwater. The subpolar North Atlantic (SPNA) is a region where the AMOC is actively developed and shaped though mixing and water mass transformation and where large amounts of heat are released to the atmosphere. Two hydrographic transbasin sections in the summers of 2014 and 2016 provide highly spatially resolved views of the SPNA velocity and property fields on a line from Canada to Greenland to Scotland. Estimates of the AMOC, isopycnal (gyre‐scale) transport, and heat and freshwater transport are derived from the observations. The overturning circulation, the maximum in northward transport integrated from the surface to seafloor and computed in density space, has a high range, with 20.6 ± 4.7 Sv in June–July 2014 and 10.6 ± 4.3 Sv in May–August 2016. In contrast, the isopycnal (gyre‐scale) circulation was lowest in summer 2014: 41.3 ± 8.2 Sv compared to 58.6 ± 7.4 Sv in 2016. The heat transport (0.39 ± 0.08 PW in summer 2014, positive is northward) was highest for the section with the highest AMOC, and the freshwater transport was largest in summer 2016 when the isopycnal circulation was high (−0.25 ± 0.08 Sv). Up to 65% of the heat and freshwater transport was carried by the isopycnal circulation, with isopycnal property transport highest in the western Labrador Sea and the eastern basins (Iceland Basin to Scotland)., Key Points The subpolar North Atlantic Meridional Overturning Circulation was 20.6 ± 4.7 Sv in summer 2014 and 10.6 ± 4.3 Sv in summer 2016The isopycnal circulation was 41.4 ± 8.2 Sv in 2014 and 58.6 ± 7.4 Sv in 2016, carrying up to 65% of the total heat and freshwater transportHeat transport increased with overturning circulation (maximum 0.39 PW), freshwater transport increased with isopycnal circulation (maximum ‐0.25 Sv)

This research is the first nationally representative study to examine the relationship between actual state-level tobacco control spending in each of the 5 CDC’s Best Practices for Comprehensive Tobacco Control Program categories and cigarette sales. We employed several alternative two-way fixed-effects regression techniques to estimate the determinants of cigarette sales in the United States for the years 2008–2012. State spending on tobacco control was found to have a negative and significant impact on cigarette sales in all models that were estimated. Spending in the areas of cessation interventions, health communication interventions, and state and community interventions were found to have a negative impact on cigarette sales in all models that were estimated, whereas spending in the areas of surveillance and evaluation, and administration and management were found to have negative effects on cigarette sales in only some models. Our models predict that states that spend up to seven times their current levels could still see significant reductions in cigarette sales. The findings from this research could help inform further investments in state tobacco control programs.

Accounting for occasional or intermittent e-cigarette use has yielded higher estimates of current use among U.S. adults. However, frequency of e-cigarette use by population subgroups is not well described. This study assessed e-cigarette use frequency by sociodemographic characteristics and other tobacco product use among U.S. adults.This study analyzed combined data from the 2012-2013 (n=60,192) and 2013-2014 (n=75,233) National Adult Tobacco Survey, a telephone-based survey of U.S. adults aged ≥18 years, to assess frequency of e-cigarette use (daily, some days, rarely) by sex, age, race/ethnicity, education, annual household income, U.S. region, marital status, sexual orientation, and cigarette smoking and other tobacco product use (cigars, cigarillos, little filtered cigars; traditional pipes; water pipes; and chewing tobacco, snuff, dip, snus, and dissolvable tobacco products). Analyses took place in 2016.Among current e-cigarette users, 19.3% used daily, 29.3% used some days, and 51.4% used rarely. Daily use was lowest among younger adults, Hispanics, and those who were single, never married, or not living with a partner; and greatest among non-Hispanic Asians (p0.0001). Among current e-cigarette users, 25.3% were cigarette-only smokers, 52.8% smoked cigarettes and used other tobacco products, 5.5% used other tobacco products only, 6.5% were former cigarette-only smokers, 6.7% were former users of cigarettes and other tobacco products, 1.3% were former other tobacco product users only, and 1.8% never used cigarettes or other tobacco products.E-cigarette use frequency varies by sociodemographic characteristics and other tobacco use. Further surveillance, particularly related to frequency of e-cigarette use and its impact on cigarette cessation, could inform public health policy, planning, and practice.

Background We investigated the relationship between receptivity to electronic cigarette (e-cigarette) advertisements at baseline and e-cigarette use at follow-up among adult baseline non-users of cigarettes and e-cigarettes. Material and Methods A nationally representative online panel was used to survey non-users of cigarettes and e-cigarettes (n = 2191) at baseline and 5-month follow-up. At baseline, respondents were shown an e-cigarette advertisement and asked if they were aware of it (exposure). Among those exposed, receptivity was self-rated for each ad using a validated scale of 1 to 5 for agreement with each of six items: “worth remembering,” “grabbed my attention,” “powerful,” “informative,” “meaningful,” and “convincing.” Logistic regression was used to measure the relationship between receptivity at baseline and e-cigarette use at follow-up. Results Among baseline non-users of cigarettes and e-cigarettes, 16.6% reported exposure to e-cigarette advertisements at baseline; overall mean receptivity score was 2.77. Among baseline non-users who reported exposure to e-cigarette advertisements, incidence of e-cigarette use at follow-up was 2.7%; among baseline non-users who reported not being exposed to e-cigarette advertisements, incidence of e-cigarette use at follow-up was 1.3%. The attributable risk percentage for e-cigarette initiation from e-cigarette advertisement exposure was 59.3%; the population attributable risk percentage from e-cigarette advertisement exposure was 22.6%. Receptivity at baseline was associated with e-cigarette use at follow-up (aOR = 1.57; 95% CI = 1.04–2.37). Conclusions Receptivity to e-cigarette advertisements at baseline was associated with greater odds of e-cigarette use at follow-up among baseline non-users of cigarettes and e-cigarettes. Understanding the role of advertising in e-cigarette initiation could help inform public health policy.

INTRODUCTION: The workplace is a major source of exposure to secondhand smoke from combustible tobacco products. Smokefree workplace policies protect nonsmoking workers from secondhand smoke and help workers who smoke quit. This study examined changes in self-reported smokefree workplace policy coverage among U.S. workers from 2003 to 2010–2011. METHODS: Data came from the 2003 (n = 74,728) and 2010–2011 (n = 70,749) waves of the Tobacco Use Supplement to the Current Population Survey. Among employed adults working indoors, a smokefree workplace policy was defined as a self-reported policy at the respondent’s workplace that did not allow smoking in work areas and public/common areas. Descriptive statistics were used to assess smokefree workplace policy coverage at two timepoints overall, by occupation, and by state. RESULTS: The proportion of U.S. workers covered by smokefree workplace policies increased from 77.7% in 2003 to 82.8% in 2010–2011 (p < .00001). The proportion of workers reporting smokefree workplace policy coverage increased in 21 states (p < .001) and decreased in two states (p < .001) over this period. In 2010–2011, by occupation, this proportion ranged from 74.3% for blue collar workers to 84.9% for white collar workers; by state, it ranged from 63.3% in Nevada to 92.6% in Montana. CONCLUSIONS: From 2003 to 2010–2011, self-reported smokefree workplace policy coverage among indoor adult workers increased nationally, and occupational coverage disparities narrowed. However, coverage remained unchanged in half of states, and disparities persisted across occupations and states. Accelerated efforts are warranted to ensure that all workers are protected by smokefree workplace policies. IMPLICATIONS: This study assessed changes in the proportion of indoor workers reporting being covered by smokefree workplace policies from 2003 to 2010–2011 overall and by occupation and by state, using data from the Tobacco Use Supplement to the Current Population Survey. The findings indicate that smokefree workplace policy coverage among U.S. indoor workers has increased nationally, with occupational coverage disparities narrowing. However, coverage remained unchanged in half of states, and disparities persisted across occupations and states. Accelerated efforts are warranted to ensure that all workers are protected by smokefree workplace policies.

Cystic adventitial disease (CAD) is a rare vascular disorder that involves the arteries and rarely the veins, most commonly found in the popliteal artery of male patients. Etiology of CAD is uncertain and currently without a consensus agreement. Clinically, the most common presenting symptom is claudication. Diagnosis requires a strong clinical suspicion in patients with intermittent claudication, but without other risk factors for atherosclerotic disease. Angiography, ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) can all be used for diagnosis. Treatment of CAD can be done via surgical resection or percutaneous intervention such as aspiration. CAD can rarely recur after treatment.

Objectives. To assess the proportion of electronic cigarette (e-cigarette) products sold in the United States that contain nicotine according to retail scanner data. Methods. We obtained unit sales data from January 11, 2015, to December 12, 2015, from The Nielsen Company for convenience stores; supermarkets; mass merchandisers; drug, club, and dollar stores; and Department of Defense commissaries. The data did not include purchases from tobacco specialty shops, “vape shops,” or online sources. Nicotine content was assessed by product type (disposables, rechargeables, and refills), region, and flavor status based on nicotine strength listed in the Universal Product Codes. For the 36.7% of entries lacking nicotine content information, we conducted Internet searches by brand, product, and flavor. Results. In 2015, 99.0% of e-cigarette products sold contained nicotine, including 99.0% of disposables, 99.7% of rechargeables, and 98.8% of refills. Overall, 98.7% of flavored e-cigarette products and 99.4% of nonflavored e-cigarette products contained nicotine. Conclusions. In 2015, almost all e-cigarette products sold in US convenience stores and other assessed channels contained nicotine. Public Health Implications. Findings reinforce the importance of warning labels for nicotine-containing products, ingredient reporting, and restrictions on sales to minors.

Objectives Approximately 10% (40 000) of US quitline enrollees who smoke cigarettes report current use of electronic nicotine delivery systems (ENDS); however, little is known about callers9 ENDS use. Our aim was to describe why and how quitline callers use ENDS, their beliefs about ENDS and the impact of ENDS use on callers9 quit processes and use of FDA-approved cessation medications. Design Qualitative interviews conducted 1-month postregistration. Interviews were recorded, transcribed, double-coded and analysed to identify themes. Setting Oklahoma Tobacco Helpline. Participants 40 callers aged ≥18 who were seeking help to quit smoking were using ENDS at registration and completed ≥1 programme calls. Results At 1-month postregistration interview, 80% of callers had smoked cigarettes in the last 7 days, almost two-thirds were using ENDS, and half were using cessation medications. Nearly all believed ENDS helped them quit or cut down on smoking; however, participants were split on whether they would recommend cessation medications, ENDS or both together for quitting. Confusion and misinformation about potential harms of ENDS and cessation medications were reported. Participants reported using ENDS in potentially adaptive ways (eg, using ENDS to cut down and nicotine replacement therapy to quit, and stepping down nicotine in ENDS to wean off ENDS after quitting) and maladaptive ways (eg, frequent automatic ENDS use, using ENDS in situations they did not previously smoke, cutting down on smoking using ENDS without a schedule or plan to quit), which could impact the likelihood of quitting smoking or continuing ENDS use. Conclusions These qualitative findings suggest quitline callers who use ENDS experience confusion and misinformation about ENDS and FDA-approved cessation medications. Callers also use ENDS in ways that may not facilitate quitting smoking. Opportunities exist for quitlines to educate ENDS users and help them create a coordinated plan most likely to result in completely quitting combustible tobacco.

Cigarette smoking is higher among low-income adults and individuals who reside in federally assisted housing are particularly susceptible to the adverse effects of smoking and secondhand smoke exposure. This study assessed smoking-related behaviors and health outcomes among U.S. adults who received federal housing assistance during 2006-2012. National Health Interview Survey data linked with administrative data from the U.S. Department of Housing and Urban Development were analyzed; 5218 HUD-assisted adults were assessed. Demographic characteristics associated with smoking, including frequency and consumption, were assessed among adult cigarette smokers. Fourteen adverse health outcomes were examined among cigarette smoking and nonsmoking adults. One-third (33.6%) of HUD-assisted adults were current cigarette smokers. Smoking prevalence was highest among adults aged 25-44 (42.5%), non-Hispanic whites (39.5%), and adults who resided in households with children (37.5%). Half attempted to quit in the past year; 82.1% were daily smokers; and, 35.8% of daily smokers reported smoking 20+ cigarettes a day. Multivariable analyses revealed that compared to nonsmokers, cigarette smokers had increased likelihood of reporting fair or poor health (95% CI: 1.04-1.52), chronic obstructive pulmonary disease (CI: 1.87-3.06), disability (CI: 1.25-1.83), asthma (CI: 1.02-1.55), serious psychological distress (CI: 1.39-2.52), >1 emergency room visit in the past year (CI: 1.09-1.56), and ≥10 work loss days in the past year (CI: 1.15-3.06). Adults who receive housing assistance represent an at-risk population for adverse health outcomes associated with smoking and secondhand smoke. Housing assistance programs provide a valuable platform for the implementation of evidence-based tobacco prevention and control measures, including smokefree policies.

The exchange of mass, heat, salt and anthropogenic carbon (Cant) between the South Atlantic, south of 24°S, and adjacent ocean basins is estimated from hydrographic data obtained during 2008–2009 using an inverse method. Transports of anthropogenic carbon are calculated across the western (Drake Passage), eastern (30°E) and northern (24°S) boundaries. The freshwater overturning transport of 0.09 Sv is southward, consistent with an overturning circulation that exports freshwater from the North Atlantic, and consistent with a bistable Meridional Overturning Circulation (MOC), under conditions of excess freshwater perturbation. At 30°E, net eastward Antarctic Circumpolar Current (ACC) transport, south of the Subtropical Front, is compensated by a 15.9 ± 2.3 Sv westward flow along the Antarctic boundary. The region as a whole is a substantial sink for atmospheric anthropogenic carbon of 0.51 ± 0.37 Pg C yr−1, of which 0.18 ± 0.12 Pg C yr−1 accumulates and is stored within the water column. At 24°S, a 20.2 Sv meridional overturning is associated with a 0.11 Pg C yr−1 Cant overturning. The remainder is transported into the Atlantic Ocean north of 24°S (0.28 ± 0.16 Pg C yr−1) and Indian sector of Southern Ocean (1.12 ± 0.43 Pg C yr−1), having been enhanced by inflow through Drake Passage (1.07 ± 0.44 Pg C yr−1). This underlines the importance of the South Atlantic as a crucial element of the anthropogenic carbon sink in the global oceans.

INTRODUCTION Research suggests aerosol from electronic vapor products (EVPs) has fewer harmful constituents than conventional cigarette smoke. Even so, EVPs and other nicotine-containing products are not safe to use during pregnancy. We examined perceptions among US adults regarding harm in using EVPs rather than smoking cigarettes during pregnancy. METHODS Data came from the 2015 Styles Survey, an Internet panel survey of a sample of US adults aged 18 years or older (N = 4,127). Perceived harm was assessed by asking respondents whether using EVPs was less, equally, or more harmful for pregnant women than smoking cigarettes. Descriptive statistics were used to estimate perceived harm overall and by sociodemographic characteristics and tobacco-use status. Perceived harm was assessed among all adults, women of reproductive age (18-44 years, n = 820), and women of nonreproductive age (≥45 years, n = 1,398). RESULTS Among all adults, 11.1% believed using EVPs during pregnancy was less harmful than smoking conventional cigarettes, 51.0% believed it was equally harmful, 11.6% believed it was more harmful, and 26.2% did not know. Prevalence of perception of less harm, by demographic category, was greatest among adults aged 18 to 24 years, men, non-Hispanic whites, adults with less than a high school diploma, current EVP users, and current cigarette smokers (P < .05). Prevalence of perception of less harm was greater among women of reproductive age (9.6%) than among those of nonreproductive age (7.9%) (P < .05). CONCLUSION US adults have varying levels of perceptions about the harms of EVP use versus cigarette smoking during pregnancy. Efforts are warranted to prevent nicotine exposure during pregnancy and to educate adults on the dangers of using any form of tobacco during pregnancy, including EVPs.

In the United States (U.S.), secondhand smoke (SHS) exposure causes more than 41,000 deaths among nonsmoking adults annually. Adoption of smoke-free laws in public areas has increased, but private settings such as vehicles remain a source of SHS exposure. This study assessed change in voluntary smoke-free vehicle rules and SHS exposure in personal vehicles among U.S. adults between two periods, 2009–2010 and 2013–2014, using data from the National Adult Tobacco Survey (NATS). NATS is a national landline and cellular telephone survey of non-institutionalized adults aged ≥18 years in the 50 U.S. states and the District of Columbia. We assessed percentage change in the prevalence of smoke-free vehicle rules among all adults and SHS exposure in vehicles among nonsmoking adults, overall, by sociodemographic factors (sex, age, race/ethnicity, education, marital status, annual household income, U.S. region), and by cigarette smoking status. During 2009–2010 to 2013–2014, the percentage of adults with a 100% smoke-free vehicle rule increased from 73.6% to 79.5% (% change = +8.0%; p < 0.05). Among nonsmokers, SHS exposure in vehicles in the previous 7 days decreased from 9.2% to 8.2% (% change = −10.9%; p < 0.05). Smoke-free rules in private settings such as vehicles, in coordination with comprehensive smoke-free policies in indoor public settings, can help reduce SHS exposure and promote smoke-free norms.

Global and regional ocean warming deeper than 2000 m is investigated using 35 years of sustained repeat hydrographic survey data starting in 1981. The global long-term temperature trend below 2000 m, representing the time period 1991–2010, is equivalent to a mean heat flux of 0.065 ± 0.040 W m?2 applied over the Earth's surface area. The strongest warming rates are found in the abyssal layer (4000–6000 m), which contributes to one third of the total heat uptake with the largest contribution from the Southern and Pacific Oceans. A similar regional pattern is found in the deep layer (2000–4000 m), which explains the remaining two thirds of the total heat uptake yet with larger uncertainties. The global average warming rate did not change within uncertainties pre-2000 versus post-2000, whereas ocean average warming rates decreased in the Pacific and Indian Oceans and increased in the Atlantic and Southern Oceans.

Since the early twenty-first century, improvements in understanding climate variability resulted from the growth of the ocean observing system. The potential for a closure of the Earth’s energy budget has emerged with the unprecedented coverage of Argo profiling floats, which now provide a decade (2006–2015) of invaluable information on ocean heat content changes above 2000 m. The expertise gained from Argo and repeat hydrography sections motivated the extension of the array toward the ocean bottom, which will progressively reveal the poorly known deep ocean and reduce the uncertainty of its presumed 10–15 % contribution to the global ocean warming trend of 0.65–0.80 W m?2. The sustainability and synergy of various observing systems helped to corroborate numerical models and decipher the internal variability of distinct ocean basins. Due to unique observations of the circulation in the North Atlantic, particular attention is paid to heat content changes and their relationship to dynamic variability in that region.

Outdoor places, such as parks, remain a source of secondhand smoke (SHS) exposure. We assessed attitudes toward smoke-free parks among U.S. adults. Data came from the 2009–2010 National Adult Tobacco Survey, a landline and cellular telephone survey of noninstitutionalized adults aged ≥18 in the 50 U.S. states and D.C. Descriptive statistics and logistic regression were used to assess the prevalence and sociodemographic correlates of attitudes toward smoke-free parks, overall and by current tobacco use. Overall, 38.5% of adults reported favorable attitudes toward complete smoke-free parks; prevalence ranged from 29.2% in Kentucky to 48.2% in Maine. Prevalence of favorable attitudes toward smoke-free parks was higher among nonusers of tobacco (44.6%) and noncombustible-only users (30.0%) than any combustible users (21.3%). The adjusted odds of having a favorable attitude were higher among: women; Hispanics and Black non-Hispanics, American Indian and Alaska Native non-Hispanics, and other non-Hispanics; those with an unspecified sexual orientation; and those with children aged ≤17 in the household, relative to each characteristics respective referent group. Odds were lower among: any combustible tobacco and noncombustible-only tobacco users; adults aged 45–64; and those with some college or an undergraduate degree. Opportunities exist to educate the public about the benefits of smoke-free outdoor environments.

Multiunit housing residents are at risk of secondhand smoke exposure from adjoining units and common areas. We developed this case study to document state-level strategies undertaken to address this risk. We explored program documents to identify facilitators, barriers, and outcomes. Three states (Montana, Michigan, and Nebraska) provided detailed information on multiunit housing efforts in the study time frame. We conducted a qualitative analysis using inductive coding to develop themes. Several facilitators relating to existing infrastructure included traditional and nontraditional partnerships, leadership and champions, collecting and using data, efficient use of resources, and strategic plans. We also report external catalysts, barriers, and outcomes. Significant state leadership and effort were required to provide local-level technical assistance to engage traditional and nontraditional partners. Information needs were identified and varied by stakeholder type (i.e., health vs. housing). States recommend starting with public housing authorities, so they can become resources for affordable and subsidized housing. These lessons and resources can be used to inform smoke-free multiunit housing initiatives in other states and localities.

E-cigarette use has increased rapidly among U.S. adults. However, reasons for use among adults are unclear. We assessed reasons for e-cigarette use among a national sample of U.S. adults. Data were collected via online surveys among U.S. adults aged 18 or older from April through June 2014. Descriptive and multivariate regression analyses were conducted to assess reasons for e-cigarette use among 2448 current e-cigarette users, by sociodemographic characteristics and product type. Assessed reasons included cessation/health, consideration of others, convenience, cost, curiosity, flavoring, and simulation of conventional cigarettes. Among current e-cigarette users, 93% were also current cigarette smokers. The most common reasons for e-cigarette use were cessation/health (84.5%), consideration of others (71.5%), and convenience (56.7%). The prevalence of citing convenience (adjusted prevalence ratio [aPR] = 1.49) and curiosity (aPR = 1.54) as reasons for e-cigarette use were greater among current cigarette smokers than nonsmokers (P < 0.05). The prevalence of citing flavoring as a reason for use was greater among adults aged 18 to 24 (aPR = 2.02) than 55 or older (P < 0.05). Tank use was associated with greater prevalence of citing every assessed reason except convenience and curiosity. Cessation- and health-related factors are primary reasons cited for e-cigarette use among adults, and flavorings are more commonly cited by younger adults. Efforts are warranted to provide consumers with accurate information on the health effects of e-cigarettes and to ensure that flavoring and other unregulated features do not promote nicotine addiction, particularly among young adults.