Homogeneous and heterogeneous atmospheric ozonolysis of chlorobenzene:Mechanism, kinetics and ecotoxicity assessment.

The reactions between chlorobenzene(CB) and ozone have been studied comprehensively in this paper. Chlorobenzene is a commonly found chlorinated aromatic volatile organic compound(VOC), and its emission into the atmosphere can cause harm to the ecosystem and human health. The frequent occurrence of mineral particles from sandstorms exerts a significant influence on the atmospheric chemistry of the troposphere. Mineral particles are abundant in SiO2 and Al2O3 content. Therefore, we investigated the homogeneous and heterogeneous reaction processes of CB and ozone in the atmosphere by using density functional theory (DFT) method at the M06-2X/6-311++g(3df,2p)//M06-2X/6-31+g(d,p) level. The atmospheric fate, reaction rate and toxicity evaluation of CB ozonation were studied in the gas-phase section. Toxicity evaluation results showed that ozonation of CB could effectively reduce its toxicity. For the heterogeneous process, we simulated three types of SiO2 clusters and nine types of (Al2O3)n clusters, and studied the configurations of CB adsorbed on the cluster surfaces. We found that adsorption of CB on the SiO2 clusters was achieved through hydrogen bonding, while adsorption of CB on the Al2O3 clusters was achieved through both hydrogen bonding and metal bonding. The energy for CB adsorption on the (Al2O3)n cluster surface was higher than that for the SixOy(OH)z cluster surface, and both types of clusters exhibited efficient adsorption of CB. As the SixOy(OH)z clusters grew larger, the rates for the reactions between O3 and CB increased. CB travelled long distances along the Al2O3 clusters, leading to an extended influence range.

Efficacy and Cost-Effectiveness Analysis of Internet-Based Cognitive Behavioral Therapy for Obsessive-Compulsive Disorder: Randomized Controlled Trial.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a common and chronic mental illness with a high rate of disability. Internet-based cognitive behavioral therapy (ICBT) makes online treatment available to patients and has been shown to be effective. However, 3-arm trials on ICBT, face-to-face cognitive behavioral group therapy (CBGT), and only medication are still lacking. OBJECTIVE: This study is a randomized, controlled, assessor-blinded trial of 3 groups for OCD: ICBT combined with medication, CBGT combined with medication, and conventional medical treatment (ie, treatment as usual [TAU]). The study aims to investigate the efficacy and cost-effectiveness of ICBT related to CBGT and TAU for adults with OCD in China. METHODS: In total, 99 patients with OCD were selected and randomly assigned to the ICBT, CBGT, and TAU groups for treatment for 6 weeks. The primary outcomes were the Yale-Brown Obsessive-Compulsive Scale (YBOCS) and the self-rating Florida Obsessive-Compulsive Inventory (FOCI), compared at baseline, during treatment (3 weeks), and after treatment (6 weeks), to analyze efficacy. The secondary outcome was the EuroQol Visual Analogue Scale (EQ-VAS) scores of the EuroQol 5D Questionnaire (EQ-5D). The cost questionnaires were recorded to analyze cost-effectiveness. RESULTS: Repeated-measures ANOVA was used for data analysis, and the final effective sample size was 93 (ICBT: n=32, 34.4%; CBGT: n=28, 30.1%; TAU: n=33, 35.5%). After 6-week treatment, the YBOCS scores of the 3 groups significantly decreased (P<.001), and there were no significant differences among groups. The FOCI score of the ICBT (P=.001) and CBGT (P=.035) groups was significantly lower than that of the TAU group after treatment. The total cost of the CBGT group (renminbi [RMB] 6678.45, 95% CI 4460.88-8896.01 [US $1010.36, 95% CI 678.87-1345.84]) was significantly higher than that of the ICBT group (RMB 3308.81, 95% CI 2476.89-4140.73[US $500.58, 95% CI 374.72-626.43], P<.001) and the TAU group (RMB 2259.61, 95% CI 2074.16-2445.05 [US $341.85, 95% CI 313.79-369.90], P<.001) after treatment. The ICBT group spent RMB 303.19 (US $45.97) less than the CBGT group and RMB 11.57 (US $1.75) less than the TAU group for each unit reduction in the YBOCS score. CONCLUSIONS: Therapist-guided ICBT combined with medication is as effective as face-to-face CBGT combined with medication for OCD. ICBT combined with medication is more cost-effective than CBGT combined with medication and conventional medical treatment. It is expected to become an efficacious and economic alternative for adults with OCD when face-to-face CBGT is not available. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900023840; https://www.chictr.org.cn/showproj.html?proj=39294.

Simulation degradation of bromophenolic compounds in chlorine-based advanced oxidation processes: Mechanism, microscopic and apparent kinetics, and toxicity assessment.

Chlorine-based advanced oxidation processes (AOPs) have been extensively studied to remove contaminants through generating HO• and reactive chlorine species, including ClO• and Cl•. In this work, 2,4,6-tribromoanisole (246TBA) and 2,4,6-tribromophenol (246TBP) were selected as model to investigate the reaction mechanisms and micro-kinetics of brominated contaminants with HO•, ClO• and Cl• in chlorine-based AOPs. Also, the apparent degradation kinetics of two compounds were simulated at pH 3.0-9.5 under UV/H2O2, UV/chlorine and UV/NH2Cl. Calculated results showed that neutral 246TBA and 246TBP exhibited similar reactivity to HO• and ClO•, which was different from anionic 2,4,6-tribromophenolate (246TBPT): radical adduct formation (RAF) and H atom abstraction (HAA) were predominant mechanisms for the HO• and ClO• initiated reactions of 246TBA and 246TBP, while RAF and single electron transfer (SET) for 246TBPT; the reaction rate constants of 246TBA and 246TBP with HO• and ClO• were lower than 107 M-1 s-1, and such rate constants dramatically increased to 1010 M-1 s-1 once 246TBP was deprotonated to 246TBPT. The apparent degradation kinetics of 246TBA at pH 3.0-9.5 was simulated in the order of UV/NH2Cl > UV/chlorine > UV/H2O2, and UV/chlorine and UV/NH2Cl were more effective for the removal of 246TBP and 246TBPT than UV/H2O2. UV and/or Cl• dominated 246 TBA degradation under three AOPs. The main radicals mediating 246TBP and 246TBPT degradation are respectively HO• under UV/H2O2, ClO• under UV/chlorine, and HO• and Cl• under UV/NH2Cl. The transformation products of 246TBA, 246TBP and 246TBPT, especially methoxylated and hydroxylated polybrominated diphenyl ethers (MeO-PBDEs and HO-PBDEs), were still toxic pollutants.

Resistance risk assessment for fludioxonil in Sclerotinia homoeocarpa in China.

Sclerotinia homoeocarpa causes dollar spot disease on turfgrass and is a serious problem on many species worldwide. Fludioxonil, a phenylpyrrole fungicide, is not currently registered for dollar spot control in China. In this study, the baseline sensitivity to fludioxonil was established using an in vitro assay for 105 isolates of S. homoeocarpa collected from 10 locations in different regions of China. Results indicate that the frequency distribution of effective concentration for 50% inhibition of mycelial growth (EC50) values of the S. homoeocarpa isolates was unimodal (W = 0.9847, P = .2730). The mean EC50 value was 0.0020 ±â€¯0.0006 µg/ml with a range from 0.0003 to 0.0035 µg/ml. A total of 7 fludioxonil-resistant mutants were obtained in laboratory, the mutants were stable in fludioxonil sensitivity after the 10th transfer, with resistance factor (RF) ranging from 4.320 to >13,901.4. The mutants showed a positive cross-resistance between fludioxonil and the dicarboximide fungicide iprodione, but not propiconazole, fluazinam, and thiophanate-methyl. When mycelial growth rate, pathogenicity and osmotic sensitivity were assessed, the mutants decreased in the fitness compared with their parental isolates. Sequence alignment of the histidine kinase gene Shos1 revealed a 13-bp fragment deletion only in one mutant, no mutations were observed on Shos1 in the rest resistant mutants.