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Considering that many hydrological analysis methods compare and analyze the runoff before and after the construction of the reservoir, without restoring the measured data of the hydrological station, in this case, when the length of the measured data series is short, the evaluation results will be affected. In this article, based on the runoff reduction of stations affected by water conservancy projects, an improved range of variability approach (RVA) which can be applied to 1-year hydrological change analysis is proposed by coupling the hydrological variation index with the appropriate upper and lower limit theory of RVA. As Jialing river watershed is selected as the research area, the runoff depth of Beibei station is reduced, and then the improved RVA is employed to analyze the degree of change in river water regime. It is concluded that the change degree of overall hydrological index in Beibei station is high, and the prediction of variation of water regime of Beibei station can be made with the aid of simulating the operation of cascade reservoirs, with the inflow of Beibei station in flood season to reduce, and the inflow in dry season to increase. The example verifies the effectiveness of the improved RVA method, and the analysis results can provide a reference for the adjustment of the operation mode of upstream cascade reservoirs.

In recent years, with the construction and operation of the Three Gorges Project, a series of changes have taken place in the relationship between the Yangtze River and Poyang Lake. Changes in hydrological conditions have led to problems in the Poyang Lake area such as early dry season, extended dry duration, and lower dry water level. As the largest freshwater lake in my country, Poyang Lake is an important treasure house of water resources in the middle and lower reaches of the Yangtze River. It is of great significance to study the protection and management of Poyang Lake under the changing relationship between rivers and lakes. This article analyzes the impact of changes in the relationship between rivers and lakes on the hydrological situation of the Poyang Lake area, and sorts out the problems of the ecological environment under the changes of rivers and lakes. On this basis, combined with the ongoing Poyang Lake water conservancy project, the importance of the construction of the hub is analyzed, and relevant suggestions for the current problems facing Poyang Lake are put forward.

The process of rainfall and runoff in the watershed is nonlinear which strongly depends on precipitation, evaporation, infiltration and hydrodynamic characteristics of soil. Due to the random and complex nature of the natural state of runoff, the temporal and spatial variability of rainfall and runoff in the watershed is extremely complicated. In view of the ability of system dynamics to describe multivariate, high order, multi-loop, strong nonlinear and complex feedback relationships, and to analyze the feedback between variables, the water cycle dynamics model is established by using system dynamics method. According to the dynamic characteristics of hydrological process, the dynamic process of rainfall to runoff is analyzed, and the relationships between the variables in the model are characterized by specific differential equations. The case study in the Zhexi watershed shows that this model can accurately simulate the process of water cycle in the watershed which also performs well on hydrological forecasting. It has certain practical significance for expanding new idea on hydrological forecasting modeling.

The long-term hydropower generation scheduling (LHGS) is one of the most important problems which aim to obtain a suitable scheme to maximize electrical benefits. In this paper, a gradient based Harmony search algorithm (GHS) is employed on the optimization of the cascade hydropower stations in the Jinsha River. Firstly, the original Harmony search algorithm (HS) is firstly improved by a dynamically adjustment strategy and global pitch adjustment strategy. Then random gradient strategy is adopted to improve the search speed of HS. In case study, the proposed GHS is used to solve the LHGS problem in the Jinsha River. Results show that GHS is effectiveness when dealing with LHGS problems.

Taking the source region of the Yellow River as an example, this paper first introduces the theory of energy value and its basic steps. Then combined with the Yellow River source area, the variation characteristics of precipitation and surface water resources from 1961 to 2011 in the Yellow River source area were analyzed, and both of them showed a trend of decreasing year by year. On this basis, using the theory of energy value, combined with relevant parameters, taking 2011 year as an example, further analyses the chemical energy and solar energy of water resources in the Yellow River source area, and gives the value of surface water resources. The value of water resources per unit is 1.59 yuan/m3. For the Yellow River source area, the overall value of water resources for the whole basin in 2011 is 33.55 billion yuan. It can provide a reference for the analysis of the value of surface water resources in the Yellow River Basin.

The streambed flux is variable in space; the spatial variability results in part from bedforms, but few works on streambed fluxes in channels with strongly abrupt varying bedforms are carried out. Heat as a tracer to delineate the streambed flux pattern has been widely adopted in numerous fields. In this paper, a braided channel with complicated topography was selected as study site, where the temperature was monitored. One-dimensional (1-D) analytical method based on the amplitude attenuation (Ar) and 1-D numerical method were used to interpret the temperature. As a result, streambed fluxes of a total of 50 sites in the braided channel are obtained. From the results we can know the magnitude and direction of streamed flow velocity are spatially variable, even within a 1-m distance. Then, this study summarizes five bedform-driven flux patterns: ① downward flow driven by the head difference between groundwater and stream, ② downward flow related to a meter-scale pool, ③ a transition from upward to downward flow associated with a centimeter-scale riffle, ④ horizontal flow in braided bars and ⑤ upward flow driven by vegetation roots. Overall, multiple physical mechanisms together contributed to the complex streambed flow system, which reflected great challenges for the scaling up of point-in-space seepage flux.

River flows would be influenced greatly by climate change, which may cause further stress on water resources management by altering the quantity and distribution of runoff. In this paper, taking the Hanjiang River basin for instance, projections of precipitation and temperature are generated from two GCMs under RCP8.5 scenario, an extreme condition. Then the outputs are statistically downscaled and corrected by the daily bias correction method, a hybrid method of combining the daily translation and the local intensity scaling method. The VIC distributed hydrological model is used for the runoff simulation. Results show that the projections of two GCMs consistent with each other. There is a general increase in the annual mean precipitation and temperature in the Hanjiang River Basin in the future period (2021-2099), and the annual mean runoff of the Danjiangkou reservoir increases significantly compared with historical period (1980-2010). However, the annual runoff variability would increase the flood control pressure in wet season, aggravate the conflict between power generation and water supply in dry season despite increasing the water supply capacity in storage season.

Background: Rapid population growth, urbanization, and high-intensity infrastructure development have challenged cities sustainable development. Surface water flooding occurs as a result of heavy rainfall which generates runoff that exceeds infiltration rates and local drainage capacity. In China, 70 cities have been chosen as pilot cities for sponge city construction building to address this challenge. Method: This paper takes the South Trunk Canal in Qingshan Demonstration Area of Wuhan Sponge City as the study area. Based on construct a Stormwater Management Model (SWMM), simulate and analyze the runoff process and the drainage capacity of the pipe network before and after the construction of the sponge city in typical years with high, normal and low water flows and different return periods. Result: The results show that the construction of sponge cities can significantly regulate the annual runoff in various typical target years and mitigate the overflow in 1- and 5- year return period. However, when faced with the short-duration storm events, the measures involved in urban sponge regulations are only effective for rainfall with 1-year return period. As the scale of the flood events increases, the effectiveness of urban sponge regulations becomes more limited. Discussion: To address these issues, the National Water Network Project is proposed for the construction of water system connections. The aim of this project is to rectify the shortcomings of sponge cities while also making better use of water resources to improve overall resilience. [ABSTRACT FROM AUTHOR]

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating condition affecting an increasing number of cancer survivors worldwide. However, insights into its pathophysiology and availability of effective therapies remain lacking. Dorsal root ganglia (DRG) have been studied as a key component of chemotherapeutic drug toxicity and a potential therapeutic target for CIPN treatment. This comprehensive review aims to synthesize, summarize, and correlate the results of both preclinical and clinical studies relevant to the pathophysiology and management of CIPN in relation to the DRG. Design: Review. A thorough literature search was conducted using the terms 'dorsal root ganglion' and 'chemotherapy-induced peripheral neuropathy', along with appropriate variations. Searched databases included PubMed, EMBASE, Medline, Cochrane Library, Wiley Library, and Web of Science. Inclusion criteria targeted all English language, peer-reviewed original research from the inception of these databases to the present year. Review articles, book chapters, and other nonoriginal publications were excluded. Of 134 relevant studies identified, the majority were preclinical studies elucidating how various chemotherapeutic agents, especially taxanes, disrupt neurotransmission, inflammatory processes, and apoptotic pathways within sensory neurons of DRG. Not only do these effects correlate with the presentation of CIPN, but their disruption has also been shown to reduce CIPN symptoms in preclinical models. However, clinical studies addressing DRG interventions are very limited in number and scope at this time. These results reveal various pathways within DRG that may be effective targets for CIPN treatment. While limited, clinical studies do offer promise in the utility of DRG neuromodulation in managing painful CIPN. In the future, clinical trials are needed to assess interventions aimed at these neuronal and nonneuronal pathological targets to better treat this complex condition. [ABSTRACT FROM AUTHOR]

Complex regional pain syndrome (CRPS) is a disabling condition that usually affects the extremities after trauma or surgery. At present, there is no FDA-approved pharmacological treatment for patients with CRPS. We performed this systematic review and meta-analysis to evaluate the efficacy and safety of pharmacological therapies and determine the best strategy for CRPS. We searched the databases, including PubMed, Embase, Cochrane, Web of Science, Scopus, and ClinicalTrials.gov, for published eligible randomized controlled trials (RCTs) comparing pharmacological treatment with placebo in CRPS patients. Target patients were diagnosed with CRPS according to Budapest Criteria in 2012 or the 1994 consensus-based IASP CRPS criteria. Finally, 23 RCTs comprising 1029 patients were included. We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to rate certainty (confidence in evidence and quality of evidence). Direct meta-analysis showed that using bisphosphonates (BPs) (mean difference [MD] −2.21, 95% CI −4.36–−0.06, p = 0.04, moderate certainty) or ketamine (mean difference [MD] −0.78, 95% CI −1.51–−0.05, p = 0.04, low certainty) could provide long-term (beyond one month) pain relief. However, there was no statistically significant difference in the efficacy of short-term pain relief. Ketamine (rank p = 0.55) and BPs (rank p = 0.61) appeared to be the best strategies for CRPS pain relief. Additionally, BPs (risk ratio [RR] = 1.86, 95% CI 1.34–2.57, p < 0.01, moderate certainty) and ketamine (risk ratio [RR] = 3.45, 95% CI 1.79–6.65, p < 0.01, moderate certainty) caused more adverse events, which were mild, and no special intervention was required. In summary, among pharmacological interventions, ketamine and bisphosphonate injection seemed to be the best treatment for CRPS without severe adverse events. [ABSTRACT FROM AUTHOR]

Safety, progress, and investment risks are correlated during the construction period of large-scale water transfer projects. However, previous studies have only considered individual risk factors, overlooking the potential systemic risk posed to safety, progress, and investment, as well as any underlying common cause failures. Since traditional risk analysis methods are ill-suited to addressing common cause failure, this paper's objective was to establish a comprehensive evaluation index framework and to identify the basic events of common cause failure. To do that, we developed a risk analysis method that models common cause failure based on a Bayesian network for assessing that systemic risk. The Henan Section of the Yangtze-to-Huaihe River Water Diversion Project in China was then used as a case study. The results show that a variety of common cause failure events, such as epidemic disease, design alteration, lagged approval process, heavy rain in the flood season, renewal material and failing equipment, construction accidents, and external interference, can significantly impact the safety, progress, and investment systemic risk. Design alteration poses the greatest risk, with renewal material and failing equipment exerting the strongest influence among all common cause failure events. It is also possible to elucidate the predominant causal chains; specifically, the contributing influence of each basic failure event to the systemic risk can be clarified by adjusting their respective initial state. The failure of renewal material and failing equipment was found to significantly increase the safety risk. This study effectively simulated the complex causal relationships and uncertainties of pertinent risk factors, thereby enhancing our understanding of the systemic risk associated with safety, progress, and investment in large-scale water transfer projects. [ABSTRACT FROM AUTHOR]