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This article investigates the microeconomics of employment dynamics, using a Chinese manufacturing firm-level data set over the period 1998–2007. It does so in the light of a scheme of "circular and cumulative causation," whereby firms' heterogeneous productivity gains, sales dynamics and innovation activities ultimately shape the patterns of employment dynamics. Using firm's productivity growth as a proxy for process innovation, our results show that the latter correlates negatively with firm-level employment growth. Conversely, relative productivity levels, as such a general proxy for the broad technological advantages/disadvantages of each firm, do show positive effect on employment growth in the long-run through replicator-type dynamics. Moreover, firm-level demand dynamics play a significant role in driving employment growth, which more than compensate the labor-saving effect due to technological progress. Finally, and somewhat puzzlingly, the direct effects of product innovation and patenting activities on employment growth appear to be negligible. [ABSTRACT FROM AUTHOR]

Organophosphates (OPs) are the most heavily used pesticides in China. The Chinese population, including preconceptional women, is highly exposed, yet little is known regarding the associations between OP exposure and menstruation in humans. We conducted a cross-sectional analysis in women preparing for pregnancy to investigate the relationship between biomarkers of OP exposure and menstrual cycle characteristics. From 2013 to 2015, 627 women visiting free preconception-care clinics at 2 maternity hospitals in Shanghai, China, were included. Information on menstrual cycle characteristics was obtained through questionnaires. OP exposure was assessed by measuring urine concentrations of 6 dialkylphosphate metabolites (dimethylphosphate, dimethylthiophosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate, and diethyldithiophosphate). The relationship between concentrations of dialkylphosphate metabolites and menstrual cycle characteristics was analyzed using multiple linear regression models and logistic regression models. Log-transformed levels of diethyl phosphate metabolites (the sum of diethylphosphate and diethylthiophosphate levels) were related to a higher risk of irregularity of menstrual cycles (adjusted odds ratio = 2.36, 95% confidence interval: 1.28, 4.34). Subjects with a higher concentration of diethyl phosphate metabolites (log-transformed) had a shorter duration of menstrual bleeding (adjusted β = −0.33, 95% confidence interval: −0.64, −0.02). The findings suggest that OP exposure may be associated with alterations in menstrual function in preconceptional women. [ABSTRACT FROM AUTHOR]

Objectives: To examine the association between maternal prepregnancy weight and child neurodevelopment, and the effect of gestational weight gain.Methods: Using the U.S. Collaborative Perinatal Project data, 1959–76, a total of 30 212 women with a calculable prepregnancy body mass index (BMI) and gestational weight gain, and term singleton children followed up for more than 7 years were included in this study. Intelligence quotient (IQ) was measured at 7 years of age by Wechsler Intelligence Scales.Results: Maternal prepregnancy BMI displayed inverted U-shaped associations with child IQ after adjustment for maternal age, maternal education levels, maternal race, marital status, socioeconomic status, smoking during pregnancy, parity and study center. Women with BMI at around 20 kg/m2 appeared to have the highest offspring IQ scores. After controlling for familial factors in the siblings’ sample, maternal obesity (BMI ≥30.0 kg/m2) was associated with lower Full-scale IQ (adjusted ß = −2.0, 95% confidence interval −3.5 to −0.5), and Verbal scale IQ (adjusted ß = −2.5, 95% confidence interval −4.0 to −1.0), using BMI of 18.5–24.9 kg/m2 as the reference category. Compared with children born to normal-weight women who gained 21–25 lb. during pregnancy, those born to obese women who gained more than 40 lb. had 6.5 points deficit in IQ after adjustment for potential confounders.Conclusions: Maternal prepregnancy obesity was associated with lower child IQ, and excessive weight gain accelerated the association. With obesity rising steadily, these results appear to raise serious public health concerns. [ABSTRACT FROM PUBLISHER]