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In this paper, we experimentally demonstrate an 8-Gbit/s quadrature-phase-shift-keying (QPSK) coherent underwater wireless optical communication (UWOC) link under scattering conditions at 532â nm. At the transmitter, we generate the 532-nm QPSK signal using second-harmonic generation (SHG), where the 1064-nm signal modulated with four phase levels of an 8-phase-shift-keying (8-PSK) format is phase doubled to produce the 532-nm QPSK signal. To enhance the receiver sensitivity, we utilize a local oscillator (LO) at the receiver from an independent laser source. The received QPSK data beam is mixed with the independent LO for coherent heterodyne detection. Results show that the bit error rates (BERs) of the received QPSK signal can reach below the 7% forward error correction (FEC) limit under turbid water with attenuation lengths (γL) up to 7.4 and 6.1 for 2- and 8-Gbit/s QPSK, respectively. The corresponding receiver sensitivities are -34.0 and -28.4â dBm for 2- and 8-Gbit/s QPSK, respectively.
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AIMS: This study estimated annual healthcare expenditures attributable to current e-cigarette use among US adults, including current exclusive and dual/poly e-cigarette use. METHODS: Analysing the 2015-2018 National Health Interview Survey data, we estimated the impacts of e-cigarette use on healthcare utilisation among adults aged 18+ years. Healthcare utilisation outcomes were hospital nights, emergency room (ER) visits, doctor visits and home visits. Current e-cigarette use was categorised as exclusive and dual/poly e-cigarette use. The econometric model included two equations: health status as a function of e-cigarette use and other independent variables, and healthcare utilisation as a function of health status, e-cigarette use, and other independent variables. Using an 'excess utilisation' approach, we multiplied the e-cigarette-attributable fraction derived from the model by annual health expenditures to calculate healthcare expenditures attributable to current exclusive and dual/poly e-cigarette use, the sum of which were expenditures attributable to all current e-cigarette use. RESULTS: Current exclusive and dual/poly e-cigarette use, with 0.2% and 3.5% prevalence in 2015-2018, were associated with higher odds of reporting poor health status than never tobacco users. Poor health status was associated with higher odds of using the four healthcare services and a greater number of ER and doctor visits. Annual healthcare expenditures attributable to all current e-cigarette use was $15.1 billion ($2024 per user) in 2018, including $1.3 billion attributable to exclusive e-cigarette use ($1796 per user) and $13.8 billion attributable to dual/poly e-cigarette use ($2050 per user). CONCLUSION: Adult current e-cigarette use was associated with substantial excess healthcare utilisation and expenditures.
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Sistemas Eletrônicos de Liberação de Nicotina , Vaping , Adulto , Humanos , Estados Unidos/epidemiologia , Gastos em Saúde , Vaping/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: Previous research quantifying the relationship between tobacco use and food insecurity has focused on cigarette smoking. E-cigarette use has become popular in recent years. Drawing on large, population-based survey data, this study augments the previous research, considering the association of e-cigarette use with food insecurity among low-income adults. METHODS: We analysed data from the California Health Interview Survey in 2014-2019. The study sample consisted of 25 948 respondents aged 18-64 who lived in low-income (<200% of the Federal Poverty Level) households. Multivariable logistic regression models were estimated to examine the associations of e-cigarette use as well as dual use of e-cigarettes and cigarettes with food insecurity. RESULTS: Of California low-income adults, 6.4% identified as current e-cigarette users (3.0% dual users of e-cigarettes and cigarettes, and 3.4% sole e-cigarette users) and 43.0% reported food insecurity. After controlling for confounding factors, food insecurity was significantly more likely to be reported among current e-cigarette users (adjusted OR (AOR)=1.67; 95% CI 1.25 to 2.23) compared with never e-cigarette users, and among dual users (AOR=2.21; 95% CI 1.63 to 3.00), current sole e-cigarette users (AOR=1.66; 95% CI 1.15 to 2.40), and current sole cigarette smokers (AOR=1.46; 95% CI 1.22 to 1.76) compared with never tobacco users. The odds of food insecurity among dual users were significantly greater than sole cigarette smokers but not statistically different from sole e-cigarette users. CONCLUSIONS: Using e-cigarette is an associated risk factor for food insecurity among low-income adults. Dual use of e-cigarettes and cigarettes has a significantly greater risk of food insecurity compared with smoking cigarettes alone.
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Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Adulto , Humanos , Vaping/epidemiologia , Fumantes , PobrezaRESUMO
We design a graded-index ring-core fiber with a GeO2-doped silica ring core and SiO2 cladding. This fiber structure can inhibit the effect of spin-orbit coupling to mitigate the power transfer among different modes and eventually enhance the orbital angular momentum (OAM) mode purity. By changing the high-index ring core from the step-index to parabolic graded-index profile, the purity of the OAM1,1 mode can be improved from 86.48% to 94.43%, up by 7.95%. The proposed fiber features a flexible structure, which can meet different requirements for mode order, effective mode area, etc. Simulation results illustrate that the parabolic-index ring-core fiber is promising in enhancing the OAM mode purity, which could potentially reduce the channel crosstalk in mode-division-multiplexed optical communication systems.
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A well designed ring-core fiber can theoretically support numerous orbital angular momentum (OAM) modes with low crosstalk for space-division-multiplexing (SDM) data transmission, which is considered as a promising solution for overcoming the capacity crunch in optical communication network. However, the accumulated chromatic dispersion in OAM-fiber could limit the data speed and transmission distance of communication systems. A potential solution is to insert a dispersion compensation ring-core fiber with opposite-sign of dispersion in the transmission fiber along the fiber link. In this work, we propose a triple ring-core fiber with broadband negative dispersion. A highest negative dispersion of -24.47 ps/(nm·km) at 1550 nm and an average dispersion slope in the C band from -0.182 ps/(nm2·km) to 0.065 ps/(nm2·km) can be achieved to compensate multi-order dispersion. The effects of Ge-doping concentration fluctuation in the high-index ring core and fabrication errors on fiber geometric structures are also investigated. Furthermore, the effective mode area decreases as the widths of high-index rings increase due to the enhanced confinement ability. The designed triple ring-core fiber could offer potential for compensating OAM fiber links with positive dispersions.
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We propose and design a 19-ring-air-core fiber that can support about 3000 orbital angular momentum (OAM) modes (156 modes in each ring) with <-80â dB inter-ring cross talk across the entire C and L bands after 100-km fiber propagation. Moreover, the eigenmodes are all separated from their adjacent modes by effective index differences >2.67 × 10-4 and mode groups by > 1.90 × 10-2, which can guarantee the stable transmission of OAM modes. This designed fiber is a potential candidate for applications in spatial division multiplexing (SDM) of optical channels to improve the capacity of next-generation high-speed optical communication systems, especially in short-distance applications. In this Letter, we also show the relationship between supported OAM mode numbers, total cross talk, and effective refractive index of intra-ring modes during the optimization of fiber through numerical simulations. It can provide a related reference for the future design of multi-ring-core fibers.
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AIMS: To examine the relationship between changes in electronic cigarette (e-cigarette) use and subsequent cigarette smoking cessation. METHODS: Using data from the Population Assessment of Tobacco and Health Study (wave 1-wave 4), we analysed a study cohort of 3014 current adult cigarette smokers at wave 1 who tried to quit during the past 12 months. We categorised changes in e-cigarette use from wave 1 to wave 2 as: daily initiation, non-daily initiation, increase to daily use, increase to non-daily use, stable daily use, stable non-daily use, decrease from daily use, quit non-daily use and non-use. We estimated multivariable logistic regressions on short-term (≥1 month and <12 months) cigarette smoking cessation at wave 3 and long-term (≥12 months) cigarette smoking cessation at wave 4. We conducted sensitivity analyses using alternative study cohorts. RESULTS: Among the study cohort, 2.4% initiated daily, 7.5% initiated non-daily, 1.0% increased to daily, 1.4% increased to non-daily, 1.5% maintained daily, 3.0% maintained non-daily, 2.4% decreased from daily and 3.8% quit non-daily e-cigarette use between waves 1 and 2; 7.9% and 6.9% reported short-term and long-term cigarette smoking cessation. 15.1% of short-term and 16.3% of long-term cigarette quitters used e-cigarettes. Compared with non-users, smokers who initiated daily, increased to daily or quit non-daily e-cigarette use between waves 1 and 2 had higher odds of short-term cigarette smoking cessation at wave 3. These results are robust to different study cohort specifications. CONCLUSION: The findings suggest a complex relationship between changes in e-cigarette use and subsequent cigarette smoking cessation.
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In this paper, we design a silica-cladded Germania-doped ring-core fiber (RCF) that supports orbital angular momentum (OAM) modes. By optimizing the fiber structure parameters, the RCF possesses a near-zero flat dispersion with a total variation of <±30 ps/nm/km over 1770 nm bandwidth from 1040 to 2810 nm for the OAM1,1 mode. A beyond-two-octave supercontinuum spectrum of the OAM1,1 mode is generated numerically by launching a 40 fs 120 kW pulse train centered at 1400 nm into a 12 cm long designed 50 mol% Ge-doped fiber, which covers 2130 nm bandwidth from 630 nm to 2760 nm at −40 dB of power level. This design can serve as an efficient way to extend the spectral coverage of beams carrying OAM modes for various applications.
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In this paper, we propose and design a multi-orbital-angular-momentum multi-ring air-core fiber, which has seven high-index rings with each ring supporting 62 radially fundamental OAM modes across C and L bands (from 1530 nm to 1625 nm), i.e. 434 OAM modes in total. The designed fiber features >4×10-4 intra-ring modal indices difference for OAM modes with the same topological charge l in a ring across the C and L bands. Moreover, it can keep <-52 dB crosstalk between the OAM modes in the adjacent rings at 1550 nm, and <-24 dB crosstalk across C and L bands after 100-km fiber propagation. This kind of seven-air-core-ring fiber would be a robust candidate for transmitting efficient OAM modes and boosting the capacity of optical fiber communications systems.
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As the dimension of orbital angular momentum (OAM) is orthogonal to the other degrees of freedom for photon, such as wavelength, it can be utilized to further increase data capacity in the wavelength division multiplexing (WDM) systems. However, the non-zero dispersion-shifted fiber (NZDSF) for the OAM mode has not yet been investigated or even proposed. In this work, we propose and design a ring fiber with low chromatic dispersion for the HE2,1 mode, which can serve as NZDSF for its corresponding OAM1,1 mode. A low dispersion of 3.3 ps/(nm·km) at 1550 nm and <2.9 ps/(nm·km) dispersion variation from 1530 to 1565 nm for the OAM1,1 mode is achieved in simulation, which satisfies the standard of the ITU-T G.655.C. The designed fiber with ring width from 1.5 µm to 3.5 µm can support the OAM1,1 mode within the C-band, and a large effective area of about 646 µm2 is obtained. We also note that the fiber with larger inner radius and ring width are more tolerant to the perturbations, such as fiber ellipticity and bending. In the fiber-based optical communication systems, the designed ring fiber could be used as a candidate for supporting OAM modes with low dispersion and reduced nonlinear effects.
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A Gram-stain-negative bacterium, designated as YN2T, that is capable of degrading 1,4-dioxane, was isolated from active sludge collected from a wastewater treatment plant in Harbin, PR China. Cells of strain YN2T were aerobic, motile, pleomorphic rods, mostly twisted, and contained the water-insoluble yellow zeaxanthin dirhamnoside. Strain YN2T grew at 10-40 °C (optimum, 30 °C), pH 5.0-8.0 (pH 7.0) and with 0-1â% (w/v) NaCl (0.1â%). It also could grow chemolithoautotrophically and fix N2 when no ammonium or nitrate was supplied. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YN2T belongs to the genus Xanthobacter and shares the highest pairwise identity with Xanthobacter autotrophicus 7cT (98.6â%) and Xanthobacter flavus 301T (98.4â%). The major respiratory quinone was ubiquinone-10. Chemotaxonomic analysis revealed that the strain possesses C16â:â0, C19â:â0 cyclo ω8c and C18â:â1 ω7c as the major fatty acids. The DNA G+C content was 67.95âmol%. Based on genome sequences, the DNA-DNA hybridization estimate values between strain YN2T and X. autotrophicus 7cT, X. flavus 301T and X. tagetidis TagT2CT (the only three species of Xanthobacter with currently available genomes) were 31.70, 31.30 and 28.50â%; average nucleotide identity values were 85.23, 84.84 and 83.59â%; average amino acid identity values were 81.24, 80.23 and 73.57â%. Based on its phylogenetic, phenotypic, and physiological characteristics, strain YN2T is considered to represent a novel species of the genus Xanthobacter, for which the name Xanthobacter dioxanivorans sp. nov. is proposed. The type strain is YN2T (=CGMCC 1.19031T=JCM 34666T).
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Dioxanos/metabolismo , Filogenia , Esgotos/microbiologia , Xanthobacter , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química , Purificação da Água , Xanthobacter/classificação , Xanthobacter/isolamento & purificaçãoRESUMO
INTRODUCTION: On April 1, 2017, California Proposition 56 (Prop 56) was implemented, increasing the excise tax on cigarettes by $2/pack. This study compares the association of Prop 56 with smoking prevalence and smoking intensity across racial/ethnic groups, further examining distinctions across income subgroups within each racial/ethnic group. AIMS AND METHODS: The study used pooled cross-sectional data from the 2012-2018 California Behavioral Risk Factor Surveillance System. We examined two outcomes: current smoking prevalence and smoking intensity conditional on current smoking. A two-part econometric model was used to estimate the association of Prop 56 with smoking prevalence and intensity using multiple logistic regression and multiple linear regression, respectively. The two-part model was run separately for all adults (full sample) and each racial/ethnic group. Within each racial/ethnic group, we ran stratified analyses by income subgroups. RESULTS: The results indicated that Prop 56 was negatively associated with smoking prevalence among full sample, Hispanic, White, and African American adults and negatively associated with smoking intensity among full sample and White smokers. Stratified analyses by race/ethnicity and income showed that Prop 56 was negatively associated with smoking prevalence among low-income full sample and White adults and among middle-income smokers in the full, Hispanic, White, African American, and Asian samples. Prop 56 was negatively associated with smoking intensity among middle-income Hispanic and high-income White smokers. The association between Prop 56 and smoking intensity was positive among high-income African American smokers. CONCLUSION: Prop 56 was associated with a reduction in smoking prevalence across multiple racial/ethnic groups, particularly within the low- and middle-income subgroups. IMPLICATIONS: Our findings indicate that the reduction in smoking prevalence immediately following the implementation of Prop 56 tobacco tax increase was significant across a variety racial/ethnic groups, particularly low- and middle-income subgroups. We found differential responses in smoking prevalence across income groups among Whites but not among racial/ethnic minorities. We found no evidence of any significance association between Proposition 56 and smoking intensity among minorities and economically vulnerable populations, except for middle-income Hispanics. Researchers, policy makers, and advocates should consider the additional merits of targeted, community-based, noneconomic tobacco control interventions in reaching low- and middle-income groups within racial/ethnic minorities.
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Etnicidade , Produtos do Tabaco , Adulto , California/epidemiologia , Estudos Transversais , Minorias Étnicas e Raciais , Humanos , Fumar , Nicotiana , Estados UnidosRESUMO
INTRODUCTION: To study the association between health care utilization and menthol cigarette use and whether the association differed between African American (AA) and non-AA smokers. METHODS: We analyzed the three most recent 2005, 2010, and 2015 National Health Interview Survey Cancer Control Supplements. After incorporating propensity score weights adjusting for observed differences between menthol and non-menthol users, we estimated Zero-Inflated Poisson models on hospital nights, emergency department visits, doctor visits, and home visits as a function of menthol use status and other covariates separately for current cigarette smokers and recent quitters (former smokers quitting cigarette smoking ≤ 4 years). RESULTS: Although current menthol smokers smoked fewer cigarettes per day than current non-menthol smokers, they did not differ from current non-menthol smokers in health care utilization. Among recent quitters, those who used to smoke menthol cigarettes had higher odds of having hospital nights than those who used to smoke non-menthol cigarettes. However, we did not find any significant association between menthol use and other health care utilization-emergency department visits, doctor visits, and home visits-among recent quitters. Moreover, compared with non-AA recent quitters, AA recent quitters had higher odds of having home visits, but fewer home visits, if they used to smoke menthol cigarettes. CONCLUSION: Menthol use was associated with greater hospitalization among recent quitters, and the association between home visits and menthol use differed between AA and non-AA recent quitters. IMPLICATIONS: This is the first study that used econometric models to study the association between health care utilization and menthol cigarette use and examine whether the association differed between AA and non-AA smokers. Our study found health care utilization did not differ by menthol use status for current smokers, although current menthol smokers smoked fewer cigarettes per day than current non-menthol smokers. However, we found menthol use was associated with higher odds of having hospital nights for recent quitters. We also found AA recent quitters had a different association between home visits and menthol use compared with non-AA recent quitters.
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Fumar Cigarros/economia , Fumar Cigarros/epidemiologia , Gastos em Saúde/estatística & dados numéricos , Mentol/análise , não Fumantes/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Fumantes/psicologia , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos , Adulto JovemRESUMO
1,4-Dioxane is a highly toxic and carcinogenic pollutant found worldwide in groundwater and soil environments. Several microorganisms have been isolated by their ability to grow on 1,4-dioxane; however, low 1,4-dioxane tolerance and slow degradation kinetics remain obstacles for their use in 1,4-dioxane bioremediation. We report here the isolation and characterization of a new strain, Xanthobacter sp. YN2, capable of highly efficient 1,4-dioxane degradation. High degradation efficiency and high tolerance to 1,4-dioxane make this new strain an ideal candidate for the biodegradation of 1,4-dioxane in various treatment facilities. The maximum degradation rate of 1,4-dioxane was found to be 1.10 mg-1,4-dioxane/h mg-protein. Furthermore, Xanthobacter sp. YN2 was shown to grow in the presence of higher than 3000 mg/L 1,4-dioxane with little to no degradation inhibition. In addition, Xanthobacter sp. YN2 could grow on and degrade 1,4-dioxane at pH ranges 5 to 8 and temperatures between 20 and 40 °C. Xanthobacter sp. YN2 was also found to be able to grow on a variety of other substrates including several analogs of 1,4-dioxane. Genome sequence analyses revealed the presence of two soluble di-iron monooxygenase (SDIMO) gene clusters, and regulation studies determined that all of the genes in these two clusters were upregulated in the presence of 1,4-dioxane. This study provides insights into the bacterial stress response and the highly efficient biodegradation of 1,4-dioxane as well as the identification of a novel Group-2 SDIMO.
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Dioxanos , Xanthobacter , Bactérias , Biodegradação AmbientalRESUMO
Biodegradation of 1,4-dioxane (dioxane) contamination has gained much attention for decades. In our previous work, we isolated a highly efficient dioxane degrader, Xanthobacter sp. YN2, but the underlying mechanisms of its extraordinary degradation performance remained unresolved. In this study, we performed a comparative transcriptome analysis of YN2 grown on dioxane and citrate to elucidate its genetic degradation mechanism and investigated the transcriptomes of different dioxane degradation stages (T0, T24, T48). We also analyzed the transcriptional response of YN2 over time during which the carbon source switched from citrate to dioxane. The results indicate that strain YN2 was a methylotroph, which provides YN2 a major advantage as a pollutant degrader. A large number of genes involved in dioxane metabolism were constitutively expressed prior to dioxane exposure. Multiple genes related to the catabolism of each intermediate were upregulated by treatment in response to dioxane. Glyoxylate metabolism was essential during dioxane degradation by YN2, and the key intermediate glyoxylate was metabolized through three routes: glyoxylate carboligase pathway, malate synthase pathway, and anaplerotic ethylmalonyl-CoA pathway. Genes related to quorum sensing and transporters were significantly upregulated during the early stages of degradation (T0, T24) prior to dioxane depletion, while the expression of genes encoding two-component systems was significantly increased at late degradation stages (T48) when total organic carbon in the culture was exhausted. This study is the first to report the participation of genes encoding glyoxalase, as well as methylotrophic genes xoxF and mox, in dioxane metabolism. The present study reveals multiple genetic and transcriptional strategies used by YN2 to rapidly increase biomass during growth on dioxane, achieve high degradation efficiency and tolerance, and adapt to dioxane exposure quickly, which provides useful information regarding the molecular basis for efficient dioxane biodegradation.
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Adaptação Fisiológica , Biomassa , Dioxanos/metabolismo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Xanthobacter/metabolismo , Xanthobacter/genéticaRESUMO
Objectives. To compare the association of California Proposition 56 (Prop 56), which increased the cigarette tax by $2 per pack beginning on April 1, 2017, with smoking behavior among low- and high-income adults.Methods. Drawing on a sample of 17 206 low-income and 21 324 high-income adults aged 21 years or older from the 2012 to 2018 California Behavioral Risk Factor Surveillance System data, we explored 2 outcomes: current smoking prevalence and smoking intensity (average number of cigarettes per day among current smokers). For each income group, we estimated a multivariable logistic regression to analyze the association of Prop 56 with smoking prevalence and a multivariable linear regression to analyze the association of Prop 56 with smoking intensity.Results. Although we observed no association between smoking intensity and Prop 56, we found a statistically significant decline in smoking prevalence among low-income adults following Prop 56. No such association was found among the high-income group.Conclusions. Given that low-income Californians smoke cigarettes at greater rates than those with higher incomes, our results provide evidence that Prop 56 is likely to reduce income disparities in cigarette smoking in California.
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Fumar , Impostos , Produtos do Tabaco , Adulto , Idoso , California/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fumar/economia , Fumar/epidemiologia , Fatores Socioeconômicos , Impostos/economia , Impostos/legislação & jurisprudência , Produtos do Tabaco/economia , Produtos do Tabaco/legislação & jurisprudência , Adulto JovemRESUMO
INTRODUCTION: This study examined the effects of cigarette price on intention to quit, quit attempts, and successful cessation among African American smokers in the United States and explored whether price effects differed by income level and menthol use status. Price effects were further compared to White counterparts. METHODS: We used pooled cross-sectional data from 2006 to 2007 and 2010 to 2011 Tobacco Use Supplements to the Current Population Survey to analyze 4213 African American recent active smokers. Three dependent variables were examined: any quit attempts in the past 12 months, successful cessation for at least 3 months, and intention to quit in the next 6 months. For each dependent variable, separate multiple logistic regression models were estimated to determine the impact of cigarette prices. RESULTS: There was no indication that price was associated with quit attempts or successful cessation, but price was positively associated with increased odds of intending to quit among African American smokers (p < .001). In contrast, prices were positively associated with intention to quit and quit attempts for White smokers. The association between price and intention to quit was significantly positive for African American low-income and menthol smokers but was not statistically significant for African American high-income and non-menthol smokers. There was no evidence of a price effect on quit attempts and successful cessation for each subgroup of African Americans. CONCLUSIONS: Tobacco tax policy alone may not be enough to increase quit attempts or successful cessation among African Americans. Community-based cessation programs tailored toward African American smokers, especially low-income menthol smokers, are needed. IMPLICATIONS: The results revealed that, among African American smokers, particularly among low-income and menthol smoking African American smokers, price appears to be positively associated with intention to quit; nevertheless, this deterrent effect does not appear to translate to actualized quit attempts or successful cessation. Increasing cigarette prices as a standalone policy may not be independently effective in increasing quit attempts and successful cessation within the African American community. Community-based cessation interventions tailored for African Americans are needed to help further translate desired cessation into actualized quit attempts.
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Negro ou Afro-Americano/psicologia , Comércio/economia , Intenção , Fumantes/psicologia , Abandono do Hábito de Fumar/economia , Fumar/economia , Produtos do Tabaco/economia , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fumantes/estatística & dados numéricos , Fumar/epidemiologia , Fumar/psicologia , Abandono do Hábito de Fumar/psicologia , Abandono do Hábito de Fumar/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Sulfamethazine (SM2) is one of the sulfonamide antibiotics that is frequently detected in aquatic environment. Given the complex structure of SM2 and its potential threat to the environment, it is necessary to determine the degradation behavior of high-concentration SM2. The mechanisms of community structure and diversity of activated sludge were analyzed. A novel SM2-degrading strain YL1 was isolated which can degrade SM2 with high concentration of 100 mg L-1. Strain YL1 was identified as Paenarthrobacter ureafaciens and there was also a significant increase in the genus during acclimation. Additional SM2 metabolic mechanisms and genomic information of YL1 were analyzed for further research. The succession of the community structure also investigated the effect of SM2 on the activated sludge. This result not only advances the current understanding of microbial ecology in activated sludge, but also has practical implications for the design and operation of the environmental bioprocesses for treatment of antimicrobial-bearing waste streams.
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Biodiversidade , Genoma Bacteriano , Consórcios Microbianos , Micrococcaceae , Sulfametazina/metabolismo , Microbiologia da Água , Micrococcaceae/genética , Micrococcaceae/isolamento & purificação , Micrococcaceae/metabolismo , Águas Residuárias/microbiologiaRESUMO
OBJECTIVE: To estimate healthcare costs attributable to secondhand smoke (SHS) exposure at home among nonsmoking adults (18+) in the U.S. METHODS: We analyzed data on nonsmoking adults (N=67,735) from the 2000, 2005, and 2010 (the latest available data on SHS exposure at home) U.S. National Health Interview Surveys. This study was conducted from 2015 to 2017. We examined hospital nights, home care visits, doctor visits, and emergency room (ER) visits. For each, we analyzed the association of SHS exposure at home with healthcare utilization with a Zero-Inflated Poisson regression model controlling for socio-demographic and other risk characteristics. Excess healthcare utilization attributable to SHS exposure at home was determined and multiplied by unit costs derived from the 2014 Medical Expenditures Panel Survey to determine annual SHS-attributable healthcare costs. RESULTS: SHS exposure at home was positively associated with hospital nights and ER visits, but was not statistically associated with home care visits and doctor visits. Exposed adults had 1.28 times more hospital nights and 1.16 times more ER visits than non-exposed adults. Annual SHS-attributable healthcare costs totaled $4.6 billion (including $3.8 billion for hospital nights and $0.8 billion for ER visits, 2014 dollars) in 2000, $2.1 billion (including $1.8 billion for hospital nights and $0.3 billion for ER visits) in 2005, and $1.9 billion (including $1.6 billion for hospital nights and $0.4 billion for ER visits) in 2010. CONCLUSIONS: SHS-attributable costs remain high, but have fallen over time. Tobacco control efforts are needed to further reduce SHS exposure at home and associated healthcare costs.
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Exposição Ambiental/efeitos adversos , Custos de Cuidados de Saúde , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Adulto , Idoso , Feminino , Inquéritos Epidemiológicos , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/economia , Estados UnidosRESUMO
Introduction: The tobacco product landscape has changed substantially. Little is known about the recent pattern of polytobacco use (at least two tobacco products) among US adults and its relationship to nicotine dependence. Methods: Using the 2012-2013 and 2013-2014 National Adult Tobacco Survey (NATS) data (N = 135 425 adults), we analyzed the prevalence and correlates of polytobacco use among each of the six categories of current tobacco user (cigarettes, cigars, pipes, hookah, e-cigarettes, and smokeless tobacco). Based on five nicotine dependence symptom measures from the NATS, difference in the prevalence of dependence symptoms between polytobacco and sole-product users for each category of tobacco user was assessed using multivariable regression analyses. Results: During 2012-2014, 25.1% of adults were current users of any tobacco product. Among them, 32.5% were poly users with the largest poly use category being dual use of cigarettes and e-cigarettes (30.2%). Poly use prevalence was the lowest among current cigarette smokers (38.7%), followed by current users of smokeless tobacco (52.4%), hookah (59.2%), cigars (69.3%), e-cigarettes (80.9%), and pipes (86.2%). Among each category of current tobacco user, the prevalence of dependence symptom was consistently greater in polytobacco users than sole users for every symptom measure. After controlling for frequency of use and demographic covariates, the difference in nicotine dependence between poly users and sole users was statistically significant and consistent across all symptom measures for each category of tobacco user. Conclusions: Between 52% and 86% of noncigarette tobacco users and nearly 40% of cigarette smokers engaged in polytobacco use. Poly users showed greater nicotine dependence than sole-product tobacco users. Implications: This study examines recent patterns of polytobacco use separately for US adult current cigarette smokers, cigar smokers, pipe smokers, hookah users, e-cigarette users, and smokeless tobacco users. By including more tobacco products, particularly e-cigarettes and hookah, this study provides more comprehensive insight into polytobacco use. This study is also unique in comparing nicotine dependence between polytobacco and sole-product users among each category of tobacco users. Our results indicate that polytobacco use is very common and is associated with greater likelihood of reporting nicotine dependence symptoms. Tobacco cessation policies and programs should be tailored to address polytobacco use.