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Orbital angular momentum (OAM) of light has attracted much attention because of its applications in many fields. Electromagnetically induced transparency (EIT) is well known as an effective method to manipulate the light fields. Now there are some increasing interests in using the EIT technology to manipulate OAM. In this work, we experimentally report on arithmetic operation of OAM of light in a solid driven by EIT. In an EIT four-level double lambda configuration, we use the optical vortex beams carrying OAM to perform slow-light four-wave mixing (FWM) without experiencing EIT storage. The conservation of OAM is satisfied in this FWM process, and the topological charge of the generated FWM signal is determined by those of the applied fields. The slow-light FWM signal accumulates the total OAM of the applied laser fields. The arithmetic operation of addition, subtraction and cancellation of OAM is effectively performed in experiment. Such OAM manipulation could have practical applications in information processing and quantum information.

In order to realize the dual-wave length lasing based on stimulated Raman scattering principle, the dual-wavelength single-mode optical fiber Raman laser is established. Firstly, 80m long G652b single-model quartz fiber is pumped by Nd3+:YAG solid pulse laser, and its output spectra when without grating which are measured and studied. Then, a linear external-cavity fiber laser is designed with fiber Bragg grating as mirrors to gain 1062nm and 1066.5nm laser output. To change pump energy (65.2uJ~100.4uJ), the mean-variances of energy percentages are all about 7.58%,and dual-wavelength energy ratio is close to 1:1. Pump pulse widths are close to 32.14ns. Finally, the main parameters of laser are analyzed too. The dual-wavelength single-mode optical fiber Raman laser can be applied to Raman amplifier filed.

To explore the environmental risk factors of different categories of congenital heart defects (CHD) and provide evidence for further risk factors and prevention research of CHD phenotypes.Data of Guangdong CHD Register Study from 2004 to 2012 were used. In the study, 3 038 CHD cases and 3 038 paired controls from 34 hospitals distributed in 17 cities were registered and related information were collected using uniform, and structured questionnaires. All the CHD phenotypes were coded according to the International Classification of Diseases 10th Revision (ICD-10) and classified into 6 categories according to their pathological features. Univariate analyses were adopted to filter potential risk factors for each category of CHD. Then multivariate conditional Logistic regression was used to calculate the odds ratios of the risk factors for each category of CHD.The risk factors for left-to-right shunt CHD included low (OR=2.63, 95%CI:2.04-3.39) or over birth weight (OR=2.21, 95%CI: 1.47-3.32), premature delivery (OR=1.95, 95%CI: 1.53-2.49), polyembryony (OR=1.99, 95%CI: 1.22-3.26), maternal low education, mother as factory worker (OR=1.62, 95%CI: 1.32-1.98), parity≥2 (OR=1.38, 95%CI: 1.13-1.69), maternal abnormal reproduction history (OR=2.29, 95%CI: 1.75-3.01), fever (OR=2.38, 95%CI: 1.26-4.48), virus infection (OR=1.80, 95%CI: 1.29-2.51), medicine usage (OR=1.73, 95%CI: 1.11-2.69), passive smoking (OR=1.69, 95%CI: 1.26-2.29), chemical agent contact (OR=8.71, 95%CI: 2.33-32.58), living in newly decorated houses (OR=2.56, 95%CI: 1.60-4.09) or room close to the main road (OR=1.40, 95%CI: 1.14-1.72) in the first 3 months of pregnancy and father as factory worker (OR=1.46, 95%CI: 1.23-1.73). The risk factors for pulmonary outflow tract obstruction CHD included low (OR=5.98, 95%CI: 2.88-12.44) or over birth weight (OR=6.56, 95%CI:1.19-36.26), maternal low education, parity≥2 (OR=2.08, 95%CI: 1.03-4.22), virus infection in the first 3 months of pregnancy (OR=4.30, 95%CI: 1.27-13.45). The risk factors for left ventricular outflow tract obstruction CHD included father as factory worker (OR=6.01, 95%CI:1.05-34.59). The risk factors for transposition of the great arteries included low birth weight (OR=12.93, 95%CI:1.14-146.26), maternal low education, mother as factory worker (OR=3.69, 95%CI:1.53-8.91). The risk factors for conditions with intra cardiac mixing of oxygenated and deoxygenated blood included parity=2 (OR=3.45, 95%CI: 1.42-8.38). The risk factors for other CHD included over birth weight (OR=4.87, 95%CI: 1.19-19.94), maternal abnormal reproduction history (OR=2.96, 95%CI: 1.14-7.68), virus infection (OR=4.92, 95%CI: 1.56-15.47), medicine usage (OR=4.90, 95%CI: 1.22-19.77) or passive smoking (OR=10.31, 95%CI: 1.25-85.05) in the first 3 months of pregnancy.The environmental risk factors were discrepant among different categories of CHD. Further risk factors study of CHD phenotypes should be performed specially. To prevent CHD, attention should be paid to the risk factors which are related to multi or complex categories of CHD.