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The oasis expansion and economic development of the Manas River Valley is one of the most successful examples in Xinjiang. In this paper, the oasis spatial distribution pattern and dynamic change were examined using imageries of Landsat MSS, TM and ETM, land use and topographic maps in six different periods (such as 1949, 1962, 1976, 1989, 1999 and 2001) over the last 50 years in the valley. The oasis expansion process could be divided into two stages according to the annual rate of oasis area increase, the fast oasization stage (from 1949 to 1976) when the oasis area expanded from 156.385 km 2 in 1949 to 3,639.491 km 2 in 1976 because of rapidly increased population and quickly enlarged farmland area; and the urbanization stage (from 1976 to 2001) when the expansion ratio of farmland slowed down, and the urbanization process quickened, the total oasis area reached 5042.440 km 2 in 2001. With the continuous expansion of oasis and farmland, a large quantity of river water was drawn into irrigation ditch and plain lakes, so only a small quantity of river water could flow into lakes, as a result, the Manas Lake dried up, salization and basification problems happened in the low-lying oasis region. The natural swamp around the lake was shrunk greatly and biodiversity decreased significantly. The driving force analysis reveals that human activities, such as reclamation and population growth, played a major role in the oasis expansion and ecological deterioration in the Manas River Valley. So further efforts should be made to improve the efficiency of water resource utility and adjust layout of the regional agricultural and animal husbandry to keep the sustainable development of oasis economic belt of the northern slope of Tianshan Mts.

Quantum chemical calculation on an entire molecule of segments of native DNA was performed in an ab initio scheme with a simulated aqueous solution environment by overlapping dimer approximation and negative factor counting method. The hopping conductivity was worked out by random walk theory and compared with recent experiment. We conclude that electronic transport in native DNA molecules should be caused by hopping among different bases as well as phosphates and sugar rings. Bloch type transport through the delocalized molecular orbitals on the whole molecular system also takes part in the electronic transport, but should be much weaker than hopping. The complementary strand of the double helix could raise the hopping conductivity for more than 2 orders of magnitudes, while the phosphate and sugar ring backbone could increase the hopping conductivity through the base stacks for about 1 order of magnitude. DNA could transport electrons easily through the base stacks of its double helix but not its single strand. Therefore, the dominate factor that influences the electronic transfer through DNA molecules is the π stack itself instead of the backbone. The final conclusion is that DNA can function as a molecular wire in its double helix form with the conditions that it should be doped, the transfer should be a multistep hopping process, and the time period of the transfer should be comparable with that of an elementary chemical reaction.

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a b s t r a c tIn this paper, a new method named MSSE-PSO (master-slave swarms shuffling evolution algorithm based on particle swarm optimization) is proposed. Firstly, a population of points is sampled randomly from the feasible space, and then partitioned into several sub-swarms (one master swarm and other slave swarms). Each slave swarm independently executes PSO or its variants, including the update of particles' position and velocity. For the master swarm, the particles enhance themselves based on the social knowledge of master swarm and that of slave swarms. At periodic stage in the evolution, the master swarm and the whole slave swarms are forced to mix, and points are then reassigned to several subswarms to ensure the share of information. The process is repeated until a user-defined stopping criterion is reached. The tests of numerical simulation and the case study on hydrological model show that MSSE-PSO remarkably improves the accuracy of calibration, reduces the time of computation and enhances the performance of stability. Therefore, it is an effective and efficient global optimization method.

a b s t r a c tWe present a study on the Hydro-Informatic Modelling System (HIMS) rainfall-runoff model for a semiarid region. The model includes nine parameters in need of calibration. A master-slave swarms, shuffling evolution algorithm based on self-adaptive dynamic particle swarm optimization (MSSE-SDPSO) is proposed to derive model parameters. In comparison with SCE-UA, PSO, MSSE-PSO and MSSE-SPSO algorithms, MSSE-SDPSO has faster convergence and more stable performance. The model is used to simulate discharge in the Luanhe River basin, a semiarid region. Compared with the SimHyd and SMAR models, HIMS model has the highest Nash-Sutcliffe efficiencies (NSE) and smallest relative errors (RE) of volumetric fitness for the periods of calibration and verification. In addition, the studies indicate that the HIMS model with all-gauge data improves runoff prediction compared with single-gauge data. A distributed HIMS model performs better than a lumped one. Finally, the Morris method is used to analyze model parameters sensitivity for the objective functions NSE and RE.

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