Predictors of reduced smoking quantity among recovering alcohol dependent men in a smoking cessation trial

Publication date: September 2018
Source:Addictive Behaviors, Volume 84
Author(s): Matthew J. Worley, Melodie Isgro, Jaimee L. Heffner, Soo Yong Lee, Belinda E. Daniel, Robert M. Anthenelli
IntroductionAdults with alcohol dependence (AD) have exceptionally high smoking rates and poor smoking cessation outcomes. Discovery of factors that predict reduced smoking among AD smokers may help improve treatment. This study examined baseline predictors of smoking quantity among AD smokers in a pharmacotherapy trial for smoking cessation.MethodsThe sample includes male, AD smokers (N = 129) with 1–32 months of alcohol abstinence who participated in a 12-week trial of medication (topiramate vs. placebo) and adjunct counseling with 6 months of follow-up. Baseline measures of nicotine dependence, AD severity, psychopathology, motivation to quit smoking, and smoking-related cognitions were used to predict smoking quantity (cigarettes per day) at post-treatment and follow-up.ResultsOverall, the sample had statistically significant reductions in smoking quantity. Greater nicotine dependence (Incidence rate ratios (IRRs) = 0.82–0.90), motivation to quit (IRRs = 0.65–0.85), and intrinsic reasons for quitting (IRRs = 0.96–0.98) predicted fewer cigarettes/day. Conversely, greater lifetime AD severity (IRR = 1.02), depression severity (IRRs = 1.05–1.07), impulsivity (IRRs = 1.01–1.03), weight-control expectancies (IRRs = 1.10–1.15), and childhood sexual abuse (IRRs = 1.03–1.07) predicted more cigarettes/day.ConclusionsSmokers with AD can achieve large reductions in smoking quantity during treatment, and factors that predict smoking outcomes in the general population also predict greater smoking reductions in AD smokers. Treatment providers can use severity of nicotine dependence and AD, motivation to quit, smoking-related cognitions, and severity of depression to guide treatment and improve outcomes among AD smokers.



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Organic cattle products: Authenticating production origin by analysis of serum mineral content

Publication date: 30 October 2018
Source:Food Chemistry, Volume 264
Author(s): Ruth Rodríguez-Bermúdez, Carlos Herrero-Latorre, Marta López-Alonso, David E. Losada, Roberto Iglesias, Marta Miranda
An authentication procedure for differentiating between organic and non-organic cattle production on the basis of analysis of serum samples has been developed. For this purpose, the concentrations of fourteen mineral elements (As, Cd, Co, Cr, Cu, Fe, Hg, I, Mn, Mo, Ni, Pb, Se and Zn) in 522 serum samples from cows (341 from organic farms and 181 from non-organic farms), determined by inductively coupled plasma spectrometry, were used. The chemical information provided by serum analysis was employed to construct different pattern recognition classification models that predict the origin of each sample: organic or non-organic class. Among all classification procedures considered, the best results were obtained with the decision tree C5.0, Random Forest and AdaBoost neural networks, with hit levels close to 90% for both production types. The proposed method, involving analysis of serum samples, provided rapid, accurate in vivo classification of cattle according to organic and non-organic production type.



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Monodisperse Zn-doped Fe3O4 formation and photo-Fenton activity for degradation of rhodamine B in water

Publication date: October 2018
Source:Journal of Physics and Chemistry of Solids, Volume 121
Author(s): Huoshi Cen, Zhaodong Nan
Zn-doped Fe3O4 can be used as a catalyst in the photo-Fenton process to degrade dye molecules dissolved in water, in which cluster-shaped Zn-doped Fe3O4 (CSZnFe) was synthesized. To enhance the catalytic activity, monodisperse Zn-doped Fe3O4 (MZnFe) was facilely synthesized by a modified solvothermal method through replacement of sodium acetate by urea as a base. The particle size of MZnFe was about 9–16 nm. MZnFe exhibits a larger surface area and higher photo-Fenton catalytic activity for degradation of rhodamine B in water than CSZnFe. Additionally, MZnFe exhibits high saturation magnetization (about 80 emu/g), which is very convenient for separation of MZnFe from solution by a magnet. The growth processes for MZnFe were proposed on the basis of results from in situ calorimetry and other techniques, which indicated different formation mechanisms for MZnFe and CSZnFe.

Graphical abstract

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The impact of seasonal varied human activity on characteristics and sources of heavy metals in metropolitan road dusts

Publication date: 1 October 2018
Source:Science of The Total Environment, Volumes 637–638
Author(s): Cong Men, Ruimin Liu, Qingrui Wang, Lijia Guo, Zhenyao Shen
Due to significant human activity, road dust is becoming contaminated by heavy metals in many cities. To comprehensively investigate the variation of contamination level and sources of heavy metals in road dust, 10 heavy metals in road dust samples from Beijing, China, in both summer and winter, were evaluated by spatial analysis using geographic information system (GIS) mapping technology and the positive matrix factorization (PMF) Model. Although the concentrations of some heavy metals between summer and winter had similarities, the differences of others and spatial distributions of heavy metals between summer and winter were considerable. The mean concentrations of As, Cd, Cr, Cu, and Fe were lower in winter, while those of Hg, Mn, Ni, Pb, and Zn were higher. According to the values of the Pollution Index (PI) and Nemerow Integrated Pollution Index (NIPI), there were no obvious differences between summer and winter, but the range between different sites in winter was nearly twice that of summer. Based on the PMF model, four sources of heavy metals in the dust samples were identified. Although the types of sources were consistent, the relative contributions of each source differed between summer and winter. Non-exhaust vehicle emissions was the most important source in summer (34.47 wt%), while fuel combustion contributed the largest proportion to the total heavy metals in winter (32.40 wt%). The impact of each source also showed spatial variation different trends in summer and winter. With the alteration of seasons, intensity of human activities also changed, such as the number of tourists, energy needs for building temperature regulation, construction, and the amount of pesticides and fertilizer. That might be the reason for the variation of heavy metal concentrations and relative contribution of their sources between summer and winter.

Graphical abstract

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Contamination of heavy metals and isotopic tracing of Pb in surface and profile soils in a polluted farmland from a typical karst area in southern China

Publication date: 1 October 2018
Source:Science of The Total Environment, Volumes 637–638
Author(s): Jing Kong, Qingjun Guo, Rongfei Wei, Harald Strauss, Guangxu Zhu, Siliang Li, Zhaoliang Song, Tongbin Chen, Bo Song, Ting Zhou, Guodi Zheng
Farmland top soils and soil profiles situated in the karst area of Guilin, Guangxi Zhuang Autonomous Region, southern China, reveal different degrees of heavy metal pollution, both in respect to the lateral as well as the vertical dimension. Pb isotope ratios clearly identify that heavy metal contributions to the soil represent the legacy of former Pb-Zn mining and smelting in the area. Depending upon soil properties, differences in the intensity of the vertical penetration of heavy metal pollution are discernible. Top soil coverage by local farmers provides little remediation. Consequently, hazardous conditions for the regional ecology, for agricultural usage and ultimately for human health remain in place. Based on chemical and isotopic results obtained, more effective remediation strategies need to be developed.

Graphical abstract

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Facile synthesis of mesoporous ZnO sheets assembled by small nanoparticles for enhanced NO2 sensing performance at room temperature

Publication date: 1 October 2018
Source:Sensors and Actuators B: Chemical, Volume 270
Author(s): Ruosong Chen, Jing Wang, Lan Xiang
Here we demonstrate a facile synthesis of nanoparticle-assembled mesoporous ZnO sheets by calcination of a novel sheet-like δ-Zn(OH)2 precursor at low temperature (100 °C). The mesoporous ZnO sheets were assembled by ultrasmall ZnO nanoparticles with an average crystal size less than 10 nm, having a high specific surface area of 87.63 m² g⁻¹. The high specific surface area, rich mesopores and oxygen vacancies, and the small crystal size of the ZnO nanoparticles contributed to the good NO2 sensing performance of the sensors. The comparison study indicated that the mesoporous ZnO sheets assembled by the smallest nanoparticles exhibited the highest response to ppm level of NO2 at room temperature (the response to 1 ppm of NO2 was 135%). Moreover, the sensor exhibited high response/recovery rates, full reversibility and good selectivity to NO2. Based on the surface depletion model, the higher response of the mesoporous ZnO sheets assembled by the smaller nanoparticles was attributed to their more significant narrowing of the conduction channel upon exposure to NO2.



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Effects of heavy metal species, concentrations, and speciation on pentachlorophenol sorption by river biofilms

Abstract

The sorption of trace organic pollutants at solid/liquid interfaces is one of the most important processes that influence their fate and behaviours in the aquatic environment. Sorption is affected by coexisting contaminants. The process and extent to which coexisting heavy metals affect the sorption of organochlorine pesticides (OCPs), especially acid radical anion heavy metals, are still unclear. Here, the effects of the species, concentrations, and speciation of the heavy metals Cu, Pb, and Cr, and the metalloid As on the sorption of pentachlorophenol (PCP), as a model OCP, by river biofilms were investigated through batch experiments. The results show that the presence of Cu, Pb, Cr, and As decreased the maximum sorption quantity of PCP onto the biofilms by 67.7, 9.2, 58.4, and 14.4%, respectively. The inhibitory effect of heavy metals on sorption decreased as the initial concentration ratios of heavy metals to PCP increased. In addition, the impact of heavy metals on PCP sorption was attributed to differences in heavy metal speciation. Cu and Pb commonly existed as divalent cations, but Cr and As existed as anionic acid radicals under the experimental conditions. The inhibitory effects of heavy metals on PCP sorption by biofilms were enhanced as the cation valence state increased, while the effects were weakened as the anionic acid radical valence state increased. Although all four heavy metals had inhibitory effects on PCP sorption by biofilms, there were distinct differences in the mechanisms causing these effects.

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