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The core of reservoir flood control operation and joint utilizable regulation is the scientific control of reservoir water level. Affected by complex realistic environment, such as emergencies, uncertain water supply and demand, etc., the reservoir water level in actual operation often deviates from initial expected path. As a result, the deviation affects subsequent scheduling and the related flood control and benefit objectives, that is the cascading effect phenomenon embedded in reservoir operation. This article proposes an evaluation index for quantifying the cascading effect of reservoir operation, which contains the persistence of impact, the loss of global state, and the failure of reservoir operation system. Based on this index system, the TOPSIS method is used to quantify the cascading effect of monthly scale reservoir operation. The K-means algorithm is applied to classify the cascading effect intensity levels. The Dongzhuang Reservoir in the Jinghe River Basin is selected as the study. Obtained results show that: 1) Compared to the impact sustainability index and system failure index, the global loss index is more sensitive to the change of reservoir operation, especially during the dry season. 2) The comprehensive cascade effect caused by disturbance in reservoir operation is the most significant in October, and relative weaker from May to July. Focusing on controlling the reservoir water level in October can help avoid the occurrence of large-scale negative cascade effects when the reservoir water level deviates from the initial optimization path. [ABSTRACT FROM AUTHOR]

In order to explore the interaction between regional water poverty and economic poverty, taking the county-level administrative regions of Shaanxi Province as the basic research unit, based on the subjective and objective comprehensive empowerment model of optimal decision-making, Shaanxi was constructed from four aspects: economic foundation, industrial structure, education and medical care. The comprehensive measurement index system of rural economic poverty in Shaanxi Province builds a comprehensive measurement index system for rural water poverty in Shaanxi Province from five aspects: resource endowment, water conservancy infrastructure, utilization, utilization capacity, and ecological environment. The coupling model, correlation coefficient and causality test method are used to conduct comprehensive measurement of water poverty and economic poverty and their coupling relationship analysis. The results show that most counties (cities) have relatively matched water poverty status with comprehensive economic poverty status, and extreme coupling is the main coupling type; It is located in Guanzhong area; the correlation coefficient between water poverty and economic poverty in non-poor counties is relatively large, while the correlation coefficient in poor counties is relatively small; at the provincial level or the level of poor counties, economic poverty leads to the occurrence of water poverty. [ABSTRACT FROM AUTHOR]

In order to alleviate the drought loss of basin in a certain extent, the Nation Flood Control and Drought Control Headquarters proposed the concept of drought-limited water level, then carried out reservoir drought control operation to reduce the degree of drought impact. The drought-limited water level,which is of great significance for improving the utilization rate of regional water resources by being set reasonably,is the control water level for the low water level operation of the reservoir, but the reservoir management based on drought-limited water level is required to adapt to the staged changes of hydrometeorological characteristics during the year. This study proposed a method of determining the staging characteristics of reservoir drought control, using the Kernel Principle Component Analysis to extract the nonlinear characteristics of the index, then give weight to index combined with the entropy method and divide the phase changes of the drought during the year with Fisher optimum dissection methods. Taking Liujiaxia Reservoir and Xiaolangdi Reservoir in the Yellow River Basin as an example respectively, the results of Liujiaxia Reservoir is divided into 3 phases:July to September, October to March, April to June; Xiaolangdi Reservoir is divided into 3 phases:July to October. November to March, April to June. [ABSTRACT FROM AUTHOR]

Land use change analysis at different periods has been very helpful for resource management and essential trends detection through time. In order to understand the changes of land use, we examine the level of land use and the strength of human activities on land use in the Yellow River Basin in recent years. Based on the analysis of the change of land use area in the study area, according to secondary divisions of water resources, importance index of land use change (Ci), proportion of land use change area (D) and vegetation index of forest and grassland (R) were used to analyze the direction and degree of land use change in eight regions of Yellow River Basin during 1980- 2015. It is found that land use in this basin underwent significant changes in the 35 years. The intensity of land changes in the Hekouzhen-Longmen section of the Yellow River Basin was the most intense. Although the degree of change in the eight sub- regions was relatively small, the absolute change area was large. The speed and degree of land use change were studied in four periods of 1980-1990, 1990-2000, 2000-2010 and 2010- 2015 by using single land use dynamic degree, comprehensive land use dynamic degree and land use degree. The results showed that compared with 1980, the area of built-up land and water changed significantly. By analyzing the rate of single land use change in different periods, the rate of desert and unused land, water and urban and rural industrial and residential land changed significantly. The other three types of land use were not noticeable because of larger base area. In terms of the study periods, the change rate during 2010-2015 was the highest, and presented an increasing trend over time. Through the analysis of land use change rate, there was an increasing trend in all the eight regions; however the increasing trend in Longyangxia region was the most obvious. Except Longyangxia and Huayuankou water resources divisions, the comprehensive index of land use degree in the entire Yellow River basin ranged from –2 to 2 from 1980 to 2015, indicating that the comprehensive level of land use in each division did not change much in this period. From this perspective, human activities have less impact on land use. The reason for this result is that the entire area of the Yellow River Basin is too large, and the areas with intense human activities are only distributed in densely populated towns and plains. In the 35- year period, human activities did not have a profound impact on forests, grasslands, and deserts. [ABSTRACT FROM AUTHOR]

Affinity ultrafiltration mass spectrometry (AUF-MS) technology is a rapid, simple and effective method for the discovery and development of small active molecule in traditional Chinese medicine (TCM). This technology was initially developed in the middle of 1990s, which was introduced to target-oriented drug discovery. Through the ligand-receptor specific binding characteristics, the affinity ultrafiltration device can facilitate the rapid screening of small-molecule ligands from the complex extracts, and high performance liquid chromatography-mass spectrometry (HPLC-MS) assists in the structural identification of potentially active small drug molecules. Thus, AUF-MS has become a powerful tool for identifying bioactive molecules from complex chemical matrixes. The general workflow of AUF-MS is not complicated: depending on the molecular weight cut-off of the semi-permeable membrane, the ligand-bound protein complexes are retained by the membrane under centrifugal force to separate the bound and unbound components of the analyte. Bound ligands are eluted from the ultrafiltration membrane by destabilizing the target-ligand complex with an organic solvent or pH change, and then the ligands are consequently subjected to analysis by LC-MS to identify and characterize the low molecular weight compounds that interact with target molecules. The classic strategies of screening active ingredients from natural product, such as the high-throughput screening methods based on ultraviolet fluorimetric or radioactive detection, the traditional phytochemical screening procedure (i.e. isolation, structure elucidation and bioactivity test), are not able to meet the urgent need of contemporary pharmacology research due to its time consumption and a high rate of false positive or negative results. In comparison with those methods, AUF-MS is easier to be operated without unnecessary isolation or purification of inactive compounds and directly screen bioactive ingredients from the Chinese herb. Also, only modest amounts of target proteins are required, which are no labeling or immobilization. AUF-LC-MS was employed to identify inhibitors of enzymes such as α-glucosidase, xanthine oxidase, neuraminidase from Chinese herb medicine. The results showed that AUF-MS performed better reproducibility and more tolerance of interferences than classic strategies for certain targets. In this review, Firstly, a brief introduction was exhibited about the general procedures of AUF-MS, and the key factors affecting the result of AUF-MS, including the selection of ultrafiltration membrane and dissociation, the dose of receptors. Secondly, the recent applications of AUF-MS to screen potential bioactivity small molecules from the natural product in the past ten years were summarized. These results based on AUF-MS to screen active compounds were expected to be valuable for discovering drug molecules candidates from TCM and efficiently designing drugs for prevention and the treatment of diseases. Finally, the future prospects of AUF-MS were also presented. AUFMS technology is expected to provide new research ideas for the screening of active components from TCM. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expressions and clinical significances of niicroRNA-221 and E-cadherin in the gastric cancer. Methods: The tumor tissues and adjacent normal tissues from 50 cases of patients with gastric cancer from the fourth affiliated hospital of Harbin medical university from 2014 to 2016 were selected as the study group and the control group respectively. The expressions of microRNA-221 and E-cadherin in both groups were examined by real-time RT-PC'R and immunohistocheniistry. Results: The expression of microRNA-221 hi the gastric cancer samples was significantly higher than that of the adjacent normal samples(P<0.05). The positive expression rate of E-cadherin hi the gastric cancer tissues was obviously lower than that of the adjacent normal tissues. The expression of microRNA-221 hi the gastric cancer was obviously associated with the TNM stage, lymph node metastasis and distant metastasis (P<0.05). E-cadherin expression was significantly associated with the lymph node metastasis and distant metastasis of gastric cancer (P<0.05). The expression of microRNA-221 hi which had negative expression of E-cadherin was obviously higher than that with positive expression of E-cadlierin hi the gastric cancer(P<0.05). Conclusions: The expression of microRNA-221 was high and expression of E-cadherin was low hi the gastric cancer which might be associated with the invasion and metastasis of gastric cancer, microRNA-221 might participate hi the invasion and metastasis of gastric cancer by Epithelial-mesenchymal transition. [ABSTRACT FROM AUTHOR]

At present, most of the drought researches are based on a single meteorological or hydrologic drought index which can not reflect the drought situation or social contradiction of supply and demand of water comprehensively. This paper studied the spatial and temporal distribution of drought in Shaanxi Province based on the method taking the social economic factors of drought into account. The natural meteorological factors are also taking into consideration. We established comprehensive drought evaluation index of Shaanxi Province with fuzzy comprehensive decision process on basis of meteorological data from 19 meteorological stations in Shaanxi from 1960 to 2013. The results showed that the spatial distribution of drought in Shaanxi Province is heterogeneous, the drought in the central Shaanxi (DI value is about 3) is more serious than in northern Shaanxi, and there is no drought in south Shaanxi at the same time where water resources are abundant. Drought occurrence frequency in Shaanxi Province is very high. The medium drought phenomenon mostly existed in the north and south (frequency approached to 80%-99.99%). The severe droughts occurred in the central Shaanxi more often (frequency approached to 79%). The method of water supply and demand evaluation considered the influence of social economy and the actual supply and demand contradiction. And the comprehensive meteorological drought index considered the effects of meteorological factors. The results of the two methods are basically identical, but only one type of drought index can not reflect the overall actual situation when there exists great difference of water quantity in different areas. In water shortage regions, the results of fuzzy comprehensive drought index are closer to the fact. In regions where water resource is extremely rich and water supply ability is strong, the results of water supply and demand method are closer to the fact. And in economic developed areas, social economy drought index is suggested. When doing researches of drought, it shall give full consideration to the natural meteorological factors and actual water supply ability. [ABSTRACT FROM AUTHOR]

Both Reservoir Inflow (RI) and Irrigation Water Demand (IWD) depend mainly on the basin-wide climate. Hence, various unpredictable (stochastic) weather and climate have induced significant variation in the water supply and demand processes in recent years. Meanwhile, the spatial similarity of climate conditions was also required to consider the relevancy between water supply and demand. More importantly, the smaller the basin is, the more considerable the relevancy is. However, the traditional one-dimensional stochastic dynamic programming cannot concern the relevancy between the multiple variables of water resources. In this study, a novel multi-dimensional stochastic dynamic programming was developed to deal with the relevancy and stochasticity in the streamflow and demand for the reservoir operations. Firstly, the one-dimensional distribution was selected to characterize the stochasticity of individual RI and IWD processes. Secondly, a Copula function of several variables was constructed using the marginal distribution. Specifically, the relevancy involved two aspects, i.e., the RI or IWD between the adjacent time intervals, and between RI and IWD at the same time. The stochasticity was referred to the individual RI, IWD, as well as the two-dimensional RI and IWD processes. Finally, the Copula function was integrated into the stochastic dynamic programming for the optimal dispatching model of the reservoir. A case study was set as an annual regulating reservoir responsible for agricultural irrigation. The results indicate that: 1) The Generalized Extreme Value (GEV) distribution was performed better on the RI and IWD in months. 2) There was remarkable relevancy of RI or IWD between a few adjacent time intervals. Moreover, there was a strong significance in April, May, June, July, September, and October. 3) Various types of Copula function were selected to model the dependent structure of RI/IWD variables at the adjacent time intervals. A Frank Copula was also employed to describe the negative relationship of dependent structure between RI and IWD at the same time. 4) The reservoir operation model considering the relevancy between RI and IWD was performed better than not. Specifically, the case study showed that the total water shortage was 10.37 × 108 m³, when considering the relevancy and stochasticity of multiple variables, which was less than before (10.49×108 m³). Nevertheless, there was a little difference between the optimal total water shortages by the two multi-dimensional stochastic dynamic programmings. This trend was attributed to a little difference of state transition probability between with and without considering the relevancy of RI and IWD. Consequently, the newly-developed multi-dimensional stochastic dynamic programming can be widely expected to extend for the multi-dimensional stochastic optimal scheduling in fields, such as the multi-energy supplementary model considering the hydropower, wind, and light energy. Moreover, a better fitting can be suitable for the current relevancy and stochasticity in multi-dimensional processes, where the wind speed and solar radiation are stochastic variables in this case. [ABSTRACT FROM AUTHOR]

Change in land use impacts the runoff availability to a large extent, which in turn, influences the surface and groundwater characteristics in a drainage area, and hence easily leads to the occurrence of droughts or floods in the basin. Therefore, it is essential to study the runoff response to land use change of a drainage basin on sub-basin level in particular, which has significant importance for planning land use patterns rationally and controlling watershed extreme hydrological events effectively. The Wei River basin (WRB), a typical arid and semi-arid region in northwest China, was selected as the study area and divided into 5 sub- basins. The main goal of current study was to investigate the spatiotemporal runoff responses to land use change in the WRB at sub-basin level. The change characteristics of land use in 1985, 1995 and 2005 in WRB were firstly analyzed with the transformation matrix. The Soil and Water Assessment Tool (SWAT) was calibrated for a baseline period of 1978-1986. Based on the results of land use change, 5 land use change scenarios were set in this paper. Then the calibrated SWAT model was run under these land use change scenarios by holding other data (e.g., meteorological and soil data) constant. The spatial runoff responses to land use change at both yearly and seasonal scales were analyzed based on the SWAT outputs. The results showed that: 1) The SWAT model had suitable application in the WRB with R2 of higher than 0.6, Nash-Suttcliffe (Ens) of higher than 0.5 and relative error (Re) of lower than 20%, which indicated that the SWAT model could be used to study the impact of land use change on runoff variation in the WRB; 2) The main land use types of WRB were farmland, woodland and grassland which accounted for 98% of the whole basin area with high transfer frequency in space, while their area change percentages were all less than 10%; the total area of other land use types was small, but their change rates were all approximate to 40% and they were mainly transformed into cultivated land; 3) The contribution of land use change to runoff variation on decade scale in 5 subzones was less than 15%; the magnitudes of yearly discharge in 3 extreme land use scenarios in Beiluo basin were woodland > farmland > grassland, and farmland > grassland > woodland in other 4 basins; 4) For the conversion of farmland to woodland scenario, the yearly runoff in Beiluo basin increased while that in other 4 sub-basins decreased, and the conversion’s impacts on the yearly runoff in the mainstream were greater than that in the tributary; for the conversion of farmland to grassland scenario, the yearly runoff in 5 sub-basins was all decreased, and the yearly runoff in the middle and lower reaches of the mainstream as well as the Jing River basin among the tributaries was decreased more significantly than other sub-basins; 5) Generally, the response degrees of seasonal runoff in the conversion of farmland to woodland scenario were higher than that in the conversion of farmland to grassland scenario; compared to other 3 kinds of seasonal runoff (i.e. spring, summer and autumn runoff), the winter runoff showed the most sensitive variation in both scenarios; the winter runoff decreased in the Jing River basin but increased in other basins in the scenario of returning farmland to forest, while it decreased in the tributary but increased in the mainstream in the scenario of returning farmland to grassland. The research results can play extremely important roles on the improvement of the ecological environment and the control of hydrological extreme drought events, and can also help to provide valuable reference for the watershed land use pattern’s planning and integrated management in WRB. [ABSTRACT FROM AUTHOR]

Under the background of frequent anthropogenic activities and global environment change, it is necessary to carry out the study of future climate change, for understanding of the characteristics of temporal and spatial evolution of future climate is of great significance to agricultural production and local water resources planning and management. Located in the middle of the Loess Plateau, China, the Jinhe River basin, the second largest river in Guanzhong area, is the major base of grain production in Shaanxi Province, which has flat land and developed agriculture since ancient times. With the establishment of the Guanzhong-Tianshui economic zone, which is a national key economic development zone and will greatly promote the rapid development of the economy in the whole western region, the security of water resources in Jinhe River basin is becoming more and more important for the economic development and local peace and stability. Therefore, in this paper, we took Jinhe River basin as the research object. Then the variation characteristics of rainfall and temperature in the future were focused and analyzed by using downscaling method and CMIP5 (coupled model intercomparison project 5) global climate models, which were applied to simulate and predict climatic elements in Jinghe River basin. There were 3 steps to establish the statistical downscaling models: firstly, determinate forecast factors based on the relationship between the factors and rainfall as well as the air temperature; then normalize the forecasting factors in the NCEP (national centers for environmental prediction) reanalysis data; eventually based on the reanalysis data and historical meteorological observation data of monthly precipitation and temperature from 7 weather stations in or around the basin from 1960 to 2010, the models were set up through screening major factors by using stepwise regression. In order to evaluate the effect of the model, the fitting degree R2, the relative error of the mean Rmean and the relative error of standard deviation Rsd were selected as the evaluation index. These models were calibrated so that the results could be satisfactory. Then, on the foundation of the calibrated models, future precipitation and temperature in the Jinhe River basin were predicted by atmospheric circulation factors came from CMIP5 experiments: the RCP8.5 (highest emission of greenhouse gases) and RCP4.5 (median emission of greenhouse gases) forcing pathways under CNRM-CM5. Finally, we analyzed the characteristics of temporal and spatial of future precipitation and temperature in the basin. The results show that: (1) The statistical downscaling models function better in simulating temperature than precipitation with higher fitting degree and lower relative error in average and standard deviation; (2) Precipitation in the basin from 2011 to 2050 showed a decreasing trend from south to north direction, and would increase only in winter with different magnitudes under 2 scenarios; moreover, the annual average precipitation was 356.41 mm under the RCP8.5 scenario, which was lower than RCP4.5 forcing pathway (374.19 mm); (3) The predicted temperature in the future was much higher under RCP8.5 scenario (9.32℃) compared to RCP4.5 scenario (8.96℃) because of greenhouse gas emission with different concentration; spatial distribution of future temperature in Jinghe River basin was characterized by higher in the north and west; besides, temperature in the basin would decrease in the late winter and early spring, but significantly increase in summer, and it was inferred that there was the possibility of occurrence of extremely high temperature in summer and extremely low temperature in winter. In conclusion, there is not only a trend of decreasing in precipitation, but also a risk of extreme weather events in Jinghe River basin, which should be paid attention to in the future water resources management and planning. [ABSTRACT FROM AUTHOR]