The roles of chloride in enhanced oxidative degradation of refractory organic pollutants are recently identified in the Cu(II)/H₂O₂/Cl^- system, but the identity of the reactive oxidants and potential conversion of inorganic chloride to organochlorine in such oxidizing environment remain obscure. Here we report that Cu(II)/H₂O₂/Cl^- system is a unique "halotolerant" Fenton-like process that works most efficiently in saline water among the five tested redox-active metals ions (i.e. Cr(VI), Ce(III), Co(II), Mn(II) and Cu(II)). The observed pseudo first-order rate constant for 2,4,6-trichlorophenol (TCP) degradation was linearly correlated with the elevated Cl^- content. The TCP degradation rate at [Cl^-]₀ = 1000 mM by the Cu(II)/H₂O₂ system was approximately 46-fold higher than that at [Cl^-]₀ = 5 mM. The optimal mineralization rate of TCP and percentage of absorbable organic halogens (AOX) decrease were 31.6% and 63.8%, respectively, in the tested Cu(II)/H₂O₂/Cl^- system. However, the detection of fused chlorinated byproducts (i.e. chloro-anthracene-pentaol, dioxine, chlorinated dibenzofuran) reminds us of cautiousness in evaluating the applicability of Cu(II)-catalyzed Fenton-like reaction, particularly while it is to be applied to the treatment of wastewater contaminated with chlorophenols. Two independent models (i.e. "Cu(III) model" and "OH model") were developed to describe the kinetics of Cu(II)/H₂O₂/Cl^- system. The failure of "OH model" to rationalize the observed AOX decay has disproved the "OH model" through reductio ad absurdum. The ability of "Cu(III) model" to adequately explain the experimental data demonstrates that Cu(III)-chloro complexes, rather than OH, is the major product resulting from reactions between Cu(I)-chloro complexes and H₂O₂ at neutral pH.

Objective: This study aimed to investigate the most notable obesity index and its optimal cut-off point of hypertension in different age groups stratified by sexes among community residents in southern China. Methods: In this cross-sectional study, 620 men and 631 women aged 18–59 years were enrolled. The independent-samples t-test and chi-square test were conducted to analyze continuous and categorical variables, respectively. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis assessed the association between the obesity indices and hypertension risk. Results: Waist–stature ratio (WSR) and waist–hip ratio (WHR) were the most notable risk factors for hypertension in young men and women, respectively. The odds ratios (ORs) of hypertension risk increased with per standard deviation (SD) in WSR and WHR (WSR: OR = 2.877, 95% confidence interval [CI] = 1.602 to 5.167; WHR: OR = 10.683, 95%CI = 2.179 to 52.376). In the middle-aged group of both sexes, body mass index (BMI) was the most distinctive risk factor for hypertension, the ORs of hypertension risk increased with per SD in BMI (men: OR = 2.297, 95%CI = 1.683 to 3.136; women: OR = 1.810, 95%CI = 1.338 to 2.450). ROC curve analysis demonstrated WSR and PI were better indicators than other indices among young men, and WSR was the best marker among young women. However, BMI and WC were the most sensitive markers in middle-aged men and women, respectively. Conclusions: In this Chinese population, the association of obesity indices and hypertension is inconsistent in different age groups and sexes. It is important to choose appropriate indicators for specific groups of people.

Objectives: Evaluate the audiometric asymmetry in Chinese industrial workers and investigate the effects of noise exposure, sex, and binaural average thresholds on audiometric asymmetry. Design: Data collected from Chinese industrial workers during a cross-sectional study were reanalyzed. Of the 1388 workers, 266 met the inclusion criteria for this study. Each subject underwent a physical examination and an otologic examination and completed a health-related questionnaire. χ² and t tests were used to examine the differences between the asymmetric and symmetric hearing loss groups. Results: One hundred thirty-one subjects (49.2%) had a binaural hearing threshold difference of 15 dB or more for at least one frequency, and there was no statistically significant difference between the left and right ears. The asymmetric hearing loss group was not exposed to higher cumulative noise levels (t = 0.522, p = 0.602), and there was no dose–response relation between asymmetry and cumulative noise levels (χ² = 6.502, p = 0.165). Men were 1.849 times more likely to have asymmetry than women were (95% confidence interval, 1.051 to 3.253). Among the workers with higher high-frequency hearing thresholds, audiometric asymmetry was 1.024 times more prevalent than that among those with lower high-frequency hearing thresholds (95% confidence interval, 1.004 to 1.044). Conclusions: The results indicated that occupational noise exposure contributed minimally to asymmetry, whereas sex and binaural average thresholds significantly affected audiometric asymmetry. There was no evidence that the left ears were worse than the right ears.

Background: There is a strong need for short and effective methods to screen for cognitive impairment. Recent studies have created short forms of the Montreal Cognitive Assessment (s-MoCA) in English-speaking populations. It is also important to develop a validated Chinese short version to detect cognitive impairment.Methods: Item response theory and computerized adaptive testing analytics were used to construct abbreviated MoCAs across a large neurological sample comprising 6,981 community-dwelling Chinese veterans.Results: Six MoCA items with high discrimination and appropriate difficulty were included in the s-MoCA. The Chinese short versions (sensitivity 0.89/0.90, specificity 0.72/0.77) are similar in performance to the full MoCA in identifying cognitive impairment (sensitivity 0.91, specificity 0.82).Conclusions: These short variants of the MoCA may serve as quick and effective instruments when the original MoCA cannot be feasibly administered in clinical services with a high patient burden and limited cognitive testing resources.

Introduction Postoperative delirium (POD) is a common neurological complication after hip fracture surgery and is associated with high morbidity and mortality in elderly patients. Although the specific mechanism of POD remains unclear, circadian rhythm disruptions have recently drawn increased attention. To date, only limited postoperative time points of plasma melatonin level measurements were recorded in previous studies, and such data cannot represent a comprehensive melatonin rhythm. The process of anaesthesia (either general anaesthesia (GA) or regional anaesthesia (RA)) is known to influence the melatonin rhythm. However, how these two anaesthesia methods differently affect the postoperative melatonin rhythm is still unknown. Therefore, we hypothesise that RA may attenuate the disruption of the melatonin rhythm, which might decrease the incidence of POD in elderly patients undergoing hip surgery. Methods and analysis In this prospective cohort clinical trial, 138 patients scheduled for hip fracture surgery will be divided into two groups to receive either GA or RA. The primary aim is to compare the circadian rhythm of melatonin secretion between the two groups and explore its association with the incidence of POD. Ethics and dissemination The study has been approved by the Medical Science Research Ethics Committees of Beijing Jishuitan Hospital (JLKS201901-04). The results of the study will be published in peer-reviewed international journals. Trial registration number ChiCTR1900027393.