Association between gestational exposure and risk of orofacial clefts: a systematic review and meta-analysis.

BACKGROUND: The occurrence of orofacial Clefts (OFCs) is a congenital disease caused by many factors. According to recent studies, air pollution has a strong correlation with the occurrence of OFCs. However, there are still some controversies about the current research results, and there is no relevant research to review the latest results in recent years. OBJECTIVE: In this paper, the authors conducted a systematic review and meta-analysis to explore the correlation between ambient air pollution and the occurrence of neonatal OFCs deformity. METHODS: We searched Pubmed, Web of science, and Embase databases from the establishment of the database to May 2023. We included observational studies on the relationship between prenatal exposure to fine particulate matter 2.5 (PM2.5), fine particulate matter 10 (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), carbon monoxide (CO) and the risk of cleft lip (CL), cleft palate (CP), cleft lip with or without palate (CL/P). the Newcastle-Ottawa quality assessment scale (NOS) was used to evaluate the quality of the literature. Funnel plot and Egger's regression were used to verify the publication bias. Random effect model or fixed effect model was used to estimate the combined relative risk (RR) and 95% confidence interval (95%CI). RESULTS: A total of eleven studies were included in this study, including four cohort studies and seven case-control studies, including 22,453 cases of OFCs. Ten studies had low risk of bias and only one study had high risk of bias. Three studies reported that PM2.5 was positively correlated with CL and CP, with a combined RR and 95%CI of 1.287(1.174,1.411) and 1.267 (1.105,1.454). Two studies reported a positive correlation between O3 and CL, with a combined RR and 95%CI of 1.132(1.047,1.225). Two studies reported a positive correlation between PM10 and CL, with a combined RR and 95%CI of 1.108 (1.017,1.206). No association was found between SO2, CO, NO2 exposure during pregnancy and the risk of OFCs. CONCLUSION: The results of this study showed that there was a significant statistical correlation between exposure to PM10, PM2.5, O3 and the risk of OFCs in the second month of pregnancy. Exposure assessment, research methods and mechanisms need to be further explored.

Phase locking of slab laser amplifiers via square wave dithering algorithm.

An active phase locking of slab laser amplifiers via square wave dithering algorithm is demonstrated experimentally. The MPD technique based on dual-level square wave phase modulation, time division multiplexing, and single detector can achieve the phase error signal of amplifiers, but without coherent demodulation process. The experimental investigation on the 208 W coherent beam combining of two slab amplifiers shows that the whole system in a closed loop performs well over a long time observation. The contrast of the coherent combined beam profile is about 87% and the combining efficiency is nearly 90.4%. The beam steering with three kinds of steering angles based on coherent beam combining using square wave dithering algorithm is demonstrated numerically.

Fiber polarization control based on a fast locating algorithm.

In this article, currently used feedback control algorithms used in the polarization controller, including a simulated annealing algorithm and a gradient algorithm, are analyzed. On this basis, a new method of polarization control feedback algorithm based on a fast locating algorithm is proposed to solve the defects of the original algorithm, such as poor convergence and an extensive time consuming search. It can reduce convergence time and improve the response speed of the polarization controllers. This new endless polarization control algorithm utilizing a four-plate polarization controller is proposed and demonstrated. The results have shown that the response time of the polarization controller is less than 1 ms. The control of polarization is achieved and the output polarization state is stable, while the light intensity fluctuated less than 2%, which can run endless resets freely.

Association between air pollutants and birth defects in Xiamen, China.

Objective: To explore the relationship between common air pollution and common birth defects, and to provide reference for the prevention of birth defects. Methods: We conducted a case-control study in Xiamen, a city in southeastern China from 2019 to 2020. Logistics regression was used to analyze the relationship between sulfur dioxide(SO2), fine particulate matter 2.5(PM2.5), nitrogen dioxide(NO2), ozone(O3), carbon monoxide(CO) and the occurrence of common birth defects such as congenital heart disease, facial cleft, and finger deformity. Results: SO2 significantly increased the risk of birth defects such as congenital heart disease, cleft lip and/or cleft palate, and ear deformity in the first and second months of pregnancy. Conclusion: Exposure to common air pollutants increases the risk of birth defects, and SO2 significantly affects the occurrence of birth defects in the first two months of pregnancy.

Active phase locking of thirty fiber channels using multilevel phase dithering method.

An active phase locking of a large-scale fiber array with thirty channels has been demonstrated experimentally. In the experiment, the first group of thirty phase controllers is used to compensate the phase noises between the elements and the second group of thirty phase modulators is used to impose additional phase disturbances to mimic the phase noises in the high power fiber amplifiers. A multi-level phase dithering algorithm using dual-level rectangular-wave phase modulation and time division multiplexing can achieve the same phase control as single/multi-frequency dithering technique, but without coherent demodulation circuit. The phase locking efficiency of 30 fiber channels is achieved about 98.68%, 97.82%, and 96.50% with no additional phase distortion, modulated phase distortion I (±1 rad), and phase distortion II (±2 rad), corresponding to the phase error of λ/54, λ/43, and λ/34 rms. The contrast of the coherent combined beam profile is about 89%. Experimental results reveal that the multi-level phase dithering technique has great potential in scaling to a large number of laser beams.