[Analysis of Hydrogen and Oxygen Stable Isotope Characteristics and Vapor Sources of Precipitation in the Guanzhong Plain].

To improve the understanding of hydrogen and oxygen stable isotope characteristics and vapor sources in the Guanzhong Plain, we collected 98 precipitation samples and corresponding meteorological data between 2015 and 2018 in Yangling, Shanxi Province, which is located in the central area of the Guanzhong Plain. The composition characteristics of the local hydrogen and oxygen stable isotopes of precipitation (δ2H, δ18O, and δ17O) and their environmental controls were analyzed, and the local meteoric water line (LMWL) and the meteoric water line of the triple oxygen isotopes were established. Three indicators (δ18O, d-excess, and 17O-excess) were used to explore the possible vapor sources of local precipitation and to quantify the contributions of ocean-source and inland-source water vapor to the precipitation. The results showed that there were obvious seasonal changes in the hydrogen and oxygen stable isotopes of precipitation in the Yangling area:water isotopes were depleted in the wet season (May to October) and enriched in the dry season (November to April of the next year). Both the slope (7.7) and intercept (9.1) of the LMWL were lower than those of the global meteoric water line (GMWL), indicating that the annual precipitation in the research area experienced variable degrees of secondary evaporation under cloud cover. The slope of the meteoric water line of the triple oxygen isotopes is 0.528, which is between that of seawater equilibrium fractionation (0.529) and water vapor diffusion into dry air (0.518), consistent with the fact that the Guanzhong area is located on the migration path of marine air mass to inland arid regions. Comprehensive analysis of δ18O, d-excess, and 17O-excess confirmed that the precipitation in the study area is jointly contributed to by the warm and humid air mass from the southeast monsoon and the dry and cold air mass from the westerly wind. Of these, approximately 55%-79% of the precipitation water vapor comes from the ocean, mainly in June to August, and about 21%-45% of the water vapor comes from inland and local evaporation, mainly from October to April. The water vapor sources of precipitation in May and September are complex and may intermittently originate from ocean and inland water vapor.

[The risk factors for chronic obstructive pulmonary disease in Xinjiang rural areas].

OBJECTIVE: To evaluate the risk factors for chronic obstructive pulmonary disease (COPD) in Xinjiang rural areas. METHODS: This was a population-based and cross-sectional survey on prevalence of COPD in Xinjiang from December 2007 to December 2010. The cluster random sampling method was performed to collect the data from 3575 people in rural areas in southern (mainly with the Uygur nationality and Han nationality) and northern (mainly with Hazakh nationality and Han nationality) parts of Xinjiang. The subjects were interviewed with questionnaires and tested with spirometry. A post-bronchodilator FEV(1)/FVC < 70% was defined as diagnostic of COPD. RESULTS: Completed data were obtained from 3489 participants. The average prevalence of COPD was 4.0% (138/3489). Of the 138 COPD patients, only 20 (14.5%, 20/138) had received diagnosis and treatment. The prevalence of COPD in Uygurs was higher (5.1%, 90/1774) than that in Hazakhs (3.3%, 26/784) and that in Hans (2.4%, 22/921). The prevalence of COPD in population older than 50 years increased significantly (> 10%, 94/743). Logistic regression model was conducted and statistical association of COPD was found with Uygurs (OR = 2.79, 95%CI: 1.71 - 4.57), older than 30 years (OR = 3.41, 95%CI: 1.62 - 7.18), family history of respiratory diseases (OR = 1.68, 95%CI: 1.11 - 2.53), and cooking behavior (OR = 1.47, 95%CI: 1.02 - 2.12). CONCLUSIONS: Higher risk for COPD was related with Uygurs, older age, family history of respiratory diseases, and cooking behavior. Whether difference in the prevalence of COPD among different ethnic is related to genetic background, and the relationship between biofuels and other risk factors for COPD need further study.

[A study on the time-effect relationship in the treatment of bronchial asthma with medicinal vesiculation therapy].

OBJECTIVE: To compare the therapeutic effects of medicinal vesiculation performed in the dog-days and ordinary-days, as well as "Xin"-days and "Geng"-days in the treatment of bronchial asthma. METHODS: A total of 162 bronchial asthma patients were divided into ordinary-days group (n = 80) and dog-days group (n = 82) according to the time sequence. Plasters made up of Gansui (Radix Euphorbiae Kansui), Baijiezi (Semen Sinapis Albae), Mahuang (Herba Ephedrae), Xixin (Herba Asari), etc. were applied to Feishu (BL 13), Fengmen (BL 12), Dingchuan (EX-B 1), Pishu (BL 20) Shenshu (BL 23), etc. during ordinary days (spring, summer, autumn and winter), dog days (the 1st-, 2nd- and 3rd-10 day periods of the hot season) for each group, once every 10 days and with 3 times being a therapeutic course. After a course of treatment, the curative effect was assessed. Before and 5 days after the treatment, venous blood samples were collected for detecting serum immunoglobulin E (IgE), lymphocyte transformation rate (LTR) and the number of eosinophile granulocytes (Eos) separately. In addition, other 80 asthma patients were treated during "Geng"-days ( (n = 42) and "Xin"-days (n = 38) separately with the same methods mentioned above. RESULTS: After one course of treatment, or the 82 and 80 cases in dog-days group and ordinary-days groups, 35 (43%) and 31(39%) experienced marked improvement in clinical symptoms, 41 (50%) and 37 (46%) had an improvement, 6 (7%) and 12 (15%) failed, with the effective rates being 93% and 85% respectively. After the treatment, serum IgE and Eos count of the two groups decreased significantly (P < 0.01, 0.05), and LTR of the two groups increased evidently (P < 0.01). No significant differences were found between two groups in the therapeutic effect and the 3 biochemical indexes. In other 80 asthma patients, of the 42 and 38 cases in "Geng"-days group and "Xin"-days group, 23 (54.76%) and 17 (44.74%) experienced marked improvement in their symptoms, 17 (40.47%) and 19 (50.00%) had an improvement, 2 (4.76%) and 2 (5.26%) failed, with the effective rates being 95.23% and 94.74% separately. No significant difference was found between two groups in the therapeutic effect (P > 0.05). CONCLUSION: Medicinal vesiculation therapy can effectively improve asthma patients' clinical symptoms, lower serum IgE and Eos count and raise LTR whenever performed in the ordinary days, dog days, "Xin" days or "Geng" days. Thus, this therapy is applicable all year round.