Spatial distribution, pollution assessment, and source identification of heavy metals in the Yellow River.

The discharge of pollutants into the Yellow River has been strictly controlled since 2013 due to the severe pollution. Thus, the overall water quality of the Yellow River has been becoming better year by year. However, the contamination status and source identification of heavy metals from the entire Yellow River remains unclear. Our results demonstrated that heavy metal contents in sediments showed little changes over time, whereas significant alleviation was observed in surface water compared to the reported metal concentrations before 2013. No heavy metal contamination was observed in surface water, and the distribution of all heavy metals in surface water fluctuated along the mainstream without a significant spatial difference. Heavy metals in sediments were assessed as low to moderate contamination degree. The majority of heavy metal concentrations were higher in the upstream and midstream than that in the downstream. Besides anthropogenic activities, the natural contribution from soil erosion of the Loess Plateau was also an important source of heavy metals in the Yellow River sediments. Our results highlight that control of anthropogenic activities and soil erosion of the Loess Plateau are necessary measures to reduce heavy metals in the Yellow River.

[Study on ABO gene polymorphism in Uighur nationality in Xinjiang of China].

OBJECTIVE: To study the distribution of ABO gene polymorphism in Uighur population in Xinjiang area of China. METHODS: DNA was extracted from 160 Uygur unrelated donorso blood and PCR-sequence specific primer analysis was performed. Some difficult samples were further directly sequenced. RESULTS: Six alleles were detected in a population of 160 Uighur individuals, the gene frequencies of which were 0.2062(A101), 0.0563(A102), 0.0156(A201), 0.0031(A205),0.1875(B01),0.5312(O01), respectively. CONCLUSION: The characteristics for AB gene structure of Xinjiang Uighur suggests that genetic polymorphism is distinguished between Xinjiang Uighur nationality and Chinese Han nationality, and both of them have discrepancy and confluent characters.