Search

ObjectiveThree methods were applied to conduct occupational health risk assessment for the working positions exposed to silicon dusts in a sanitary ceramic manufacturing factory， and the evaluation results were compared to explore the applicability of different occupational health risk assessment methods.MethodsOne large sanitary ceramic product manufacturing enterprise in Songjiang District， Shanghai was selected to conduct occupational health risk assessment for the working positions exposed to silicon dusts， using occupational hazard risk index evaluation method， exposure ratio evaluation method， and International Council on Mining and Metals （ICMM） quantitative occupational health risk assessment method . The consistency of the evaluation results of the three methods was tested using weighted Kappa method.ResultsFourteen working positions exposed to silicon dusts were identified， and three positions had excessive dust concentration： composite forming position of phase 2 workshop （0.80 mg·m-3）， addition forming position of phase 2 workshop （1.00 mg·m-3）， and glazing position of 1F in phase 2 workshop （1.50 mg·m-3）， with an excessive rate of 21.42%. The occupational hazard risk index evaluation method assessed 6 positions with no harm， 6 positions with mild harm， and 2 positions with moderate harm. The ICMM quantitative occupational health risk assessment method assessed 6 positions with potential risks， 2 positions with tolerable risks， and 6 positions with intolerable risks. The exposure ratio evaluation method assessed 8 positions with medium risk， 5 positions with high risk， and 1 position with extremely high risk. The consistency test results of the three evaluation methods were poor. The Kappa coefficient between the occupational hazard risk index evaluation method and the ICMM quantitative occupational health risk assessment method was 0.15. The Kappa coefficient between the occupational hazard risk index evaluation method and the exposure ratio evaluation method was -0.09. The Kappa coefficient between the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method was 0.04. The RR values obtained by the three evaluation methods were significantly correlated： the correlation coefficients between RRICMM quantitative assessment method and RRexposure ratio evaluation method， RROccupational hazard risk index evaluation method and RRICMM quantitative assessment method， RROccupational hazard risk index evaluation method and RRexposure ratio evaluation method were 0.915， 0.604， and 0.594， respectively. The correlation between the assessment result level and CTWA was strong.ConclusionThe occupational hazard risk index evaluation method is suitable for the working positions with low silicon dust exposure concentration， the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method are suitable for the positions with high silicon dust exposure concentration， but all these three evaluation methods have limitations. It is more reasonable to use multiple methods at the same time in actual evaluation work.

This article discusses a study on the direct alkoxylation of N,N-dialkyl amides using the Shono reaction. The researchers found that electron-donating and electron-withdrawing groups on the amide were well tolerated, while a para-nitro group lowered the reaction efficiency. They also explored the role of TMSN3 in the reaction and proposed a radical-relay process. Overall, this study provides a new strategy for the alkylation of N,N-dialkyl amides, expanding the scope of the Shono reaction. [Extracted from the article]

Thyroid cancer (TC) incidence has increased greatly during the past decades with a few established risk factors, while no study is available that has assessed the association of the Chinese Health Dietary Index (CHDI) with TC. We conducted a 1:1 matched case–control study in two hospitals in Shanghai, China. Diet-quality scores were calculated according to CHDI using a validated and reliable FFQ. Conditional logistic regression analysis and restricted cubic spline analysis were used to reveal potential associations between CHDI score and TC risk. A total of 414 pairs of historically confirmed TC patients and healthy controls were recruited from November 2012 to December 2015. The total score of cases and controls were 67·5 and 72·8, respectively (P < 0·001). The median score of total vegetables, fruit, diary products, dark green and orange vegetables, fish, shellfish and mollusk, soyabean, whole grains, dry bean and tuber in cases was significantly lower than those in controls. Compared with the reference group (≤60 points), the average (60–80 points) and high (≥80 points) levels of the CHDI score were associated with a reduced risk of TC (OR: 0·40, 95 % CI 0·26, 0·63 for 60–80 points; OR: 0·22, 95 % CI 0·12, 0·38 for ≥80 points). In age-stratified analyses, the favourable association remained significant among participants who are younger than 50 years old. Our data suggested that high diet quality as determined by CHDI was associated with lower risk of TC. [ABSTRACT FROM AUTHOR]

Radical/radical cross-coupling remains challenging due to diffusion control issues. Herein, we report a visible-light-induced radical/radical cross-coupling reaction of quaternary ammonium salts and Hantzschs via C–N and C–C bond cleavage. The current synthetic approach furnishes 1,2-diphenylethanes in moderate to good yields and provides a method for the construction of the C(sp3)–C(sp3) bond. [ABSTRACT FROM AUTHOR]