BackgroundUyghurs are one of the many populations of Central Eurasia that is considered to be genetically related to Eastern and Western Eurasian populations. However, there are some different opinions on the relative importance of the degree of Eastern and Western Eurasian genetic influence. In addition, the genetic diversity of the Uyghur in different geographic locations has not been clearly studied.ResultsIn this study, we are the first to report on the DNA polymorphism of cytochrome B in the Uyghur population located in Xinjiang in northwest China. We observed a total of 102 mutant sites in the 240 samples that were studied. The average number of mutated nucleotides in the samples was 5.126. A total of 93 different haplotypes were observed. The gene diversity and discrimination power were 0.9480 and 0.9440, respectively. There were founder and bottleneck haplotypes observed in Xinjiang Uyghurs. Xinjiang Uyghurs are more genetically related to Chinese population in genetics than to Caucasians. Moreover, there was genetic diversity between Uyghurs from the southern and northern regions. There was significance in genetic distance between the southern Xinjiang Uyghurs and Chinese population, but not between the northern Xinjiang Uyghurs and Chinese. The European vs. East Asian contribution to the ten regional Uyghur groups varies among the groups and the European contribution to the Uyghur increases from north to south geographically.ConclusionThis study is the first report on DNA polymorphisms of cytochrome B in the Uyghur population. The study also further confirms that there are significant genetic differences among the Uyghurs in different geographical locations.

To evaluate the utility of Y-STR data for DNA testing in two ethnic populations of Xinjiang province, a sample of 338 subjects (121 Kazakhs and 217 Uighurs) was tested. In the Kazakh and Uighur populations, the haplotype diversity was 0.868 and 0.996, respectively, and the discrimination capacity was 0.5950 and 0.8940, respectively. High numbers of singleton haplotypes were observed among Xinjiang Uighurs, but fewer were found in Kazakhs. Our results were also compared with geographically and linguistically close populations.

The composition and distribution of epiphytic algae on Potamogeton perfoliatus were studied in a controlled laboratory environment over 84 days under two light conditions. The study was based on a 2 × 2 factorial design with two light conditions (high and low, 200 and 80 µE m-2 s-1) and two different plant parts (apical and basal). In both light conditions, the community consisted of 18 taxa (under nine genera) of Bacillariophyceae. Amphora lineolata, Cocconeis placentula, and Diatoma hiemale were the most common and abundant species. The total algal density was significantly higher in the high light condition and on the basal plant part than in the low light condition and on the apical plant part. At termination of the experiment, basal plant parts exhibited a more uniform crust of epiphytic algae consisting of c. 95% C. placentula whereas the apical plant parts expressed a more mosaic community (under both light conditions).

In this paper, the sand break into highway problem in desert, which is caused by the sand flow blown by wind, is studied. The mathematical models are introduced by considering the fixed, semi-fixed and free sand desert fields based on the fluid dynamics and the sand particle dynamics. Different kinds of numerical models are made by changing the desert highway height, wind flow direction and its uniformity. The weak coupling method is used due to spatial relationships between air flow field and the sand flow field. Finally, by coupling the airflow field and sand flow field with desert highway, the numerical simulations of sand forming process on desert highway are conducted. The numerical results shown, that the wind blown sand breaks into highway easier when wind direction perpendicular highway and if the highway height higher than the range size of the sand surface the wind blown sand break into highway is more difficult.

Wind caused the much sediment fluxes leading to both erosion and deposits in the sandy desertification area, and the much kind of beautiful sandy desert morphologies are formed. This is really crucial to the development of the dynamic behaviour of aeolian transport of sand particles. The sand desert morphologies are representing significant information archives for understanding the desertification problem. Dynamics and numerical modeling provides an essential tool for studying the aeolian transport of sand particle and morphology of sand desert such as ripple and dune. In this study, the mathematical models based on the dynamics are analyzed by considering the several keys as saltation, creep, suspension, avalanche and its threshold condition etc. for sand morphology forming processes. Then due to sand flow field real characteristics, the establishing process of stream flow field are analyzed, and the implication relationships as well as the coupling process between uniform stream flow field and the sand flow field are analyzed. Finally, the sand flow field models is discretized, and different kinds of sandy desert morphology are simulated by considering the sand particle size and mass in fixed, semi-fixed and free sand flow field area.