Progressive optimization allocation model for carbon emission quotas: An empirical study of Jiangsu cities.

The rational allocation of carbon emission quotas is crucial for improving the orderly operation of carbon markets. As a major energy-consuming province in China, Jiangsu's cities must allocate allowable carbon emissions effectively to meet China's 2030 peaking target. This study aims to achieve an optimal allocation of carbon emission quotas by considering principles such as responsibility, efficiency, and equity. To accomplish this goal, we developed a three-stage progressive optimization allocation process. This process incorporates the entropy weight TOPSIS allocation model, zero-sum game-DEA model, and Gini coefficient. The initial allocation scheme revealed that cities in southern Jiangsu, which have higher economic development levels, also received higher carbon emission quotas, compromising efficiency and equity. In response, the second stage involves adjusting the allocation to optimize efficiency for each city, aligning the quotas more closely with historical levels. Finally, the third stage uses the Gini coefficient to further refine the allocation scheme, achieving a more balanced distribution that aligns responsibility, efficiency, and fairness. This research highlights the importance of a structured approach to carbon quota allocation, ensuring a balance that supports both environmental goals and equitable development.

Dynamic simulation for reclaimed water reuse under multi-intervention policies in China.

Unconventional water constitutes the fundamental approach to addressing global water scarcity and achieving the sustainable circulation of water resources. Due to the significant environmental advantages and economical production costs, reclaimed water has emerged as a preeminent unconventional source. However, the use in China confronts the predicament of oversupply relative to demand, requiring policy measures to overcome this challenge. Limited research exists on the combined impact of subsidies and water quality information disclosure supervision on reclaimed water utilization, potentially underestimating the practical incentivizing role of water quality information disclosure. Therefore, based on the framework of 'external environment-perceived value-utilization intention,' a multi-agent-based simulation model driven by evolutionary game theory is constructed, from micro to macro perspective, to investigate the composite effects of subsidies and water quality information disclosure supervision on public intentions for reclaimed water utilization and the evolutionary track of public decision-making. The results showed that (1) The influence of subsidies on the public's inclination toward reclaimed water has regional heterogeneity. In regions with average economic development, the subsidy policy shows an inverted U-shaped correlation with the public's intention to reclaimed water, indicating the presence of an optimal value for maximizing the promotional effect of subsidies. Conversely, the effect is less discernible in regions with higher economic development. (2) In regions with average economic development, supervision of information disclosure behavior can avert the diminishing incentivizing effects under radical subsidies, but the assistance of various supervision intensities is different. (3) In regions with higher economic development, the incentive effect of subsidies can be positively modulated by the supervision policy. Interactions between subsidy and supervision policies evoke diverse chain reactions under varying intensities in these regions, and the combination of moderate subsidies and high supervision emerges as the most optimal strategy to advance reclaimed water development.

Development of a Clinicopathological-Radiomics Model for Predicting Progression and Recurrence in Meningioma Patients.

RATIONALE AND OBJECTIVES: Tumor progression and recurrence（P/R）after surgical resection are common in meningioma patients and can indicate poor prognosis. This study aimed to investigate the values of clinicopathological information and preoperative magnetic resonance imaging (MRI) radiomics in predicting P/R and progression-free survival (PFS) in meningioma patients. METHODS AND MATERIALS: A total of 169 patients with pathologically confirmed meningioma were included in this study, 54 of whom experienced P/R. Clinicopathological information, including age, gender, Simpson grading, World Health Organization (WHO) grading, Ki-67 index, and radiotherapy history, as well as preoperative traditional radiographic findings and radiomics features for each MRI modality (T1-weighted, T2-weighted, and enhanced T1-weighted images) were initially extracted. After feature selection, the optimal performance was estimated among the models established using different feature sets. Finally, Cox survival analysis was further used to predict PFS. RESULTS: Ki-67 index, Simpson grading, WHO grading, and radiotherapy history were found to be independent predictors for P/R in the multivariate regression analysis. This clinicopathological model had an area under the curve (AUC) of 0.865 and 0.817 in the training and testing sets, respectively. The performance of the combined radiomics model reached 0.85 and 0.84, respectively. A clinicopathological-radiomics model was then established, which significantly improved the prediction of meningioma P/R (AUC = 0.93 and 0.88, respectively). Finally, the risk ratio was estimated for each selected feature, and the C-index of 0.749 was obtained. CONCLUSION: Radiomics signatures of preoperative MRI have the ability to predict meningioma at the risk of P/R. By integrating clinicopathological information, the best performance was achieved.

Distribution, source, and contamination assessment of heavy metals in surface sediments of the Zhifu Bay in northern China.

In this study, 30 surface sediment samples were collected from Zhifu Bay in northern China and analyzed for heavy metals; in addition, their concentrations and pollution status were evaluated. The distributions of Cu and Zn were similar and mainly dominated by fine-grained sediments, whereas the other heavy metal distributions were not very regular. Al was positively correlated with Cu and Zn, and weakly correlated with Pb, As, and Hg. Except for some stations that showed minor enrichment and were unpolluted to moderately polluted by Cr, Cd, and Hg, the overall quality of sediments in the study area was good. Three principal components with eigenvalues >1 were estimated, accounting for 72.06 % of the total variability and representing natural sources, natural and anthropogenic, and anthropogenic sources, respectively.

Corrigendum: High follicle-stimulating hormone level associated with risk of rheumatoid arthritis and disease activity.

[This corrects the article DOI: 10.3389/fendo.2022.862849.].

Construction of an immune-related lncRNA-miRNA-mRNA regulatory network in radiation-induced esophageal injury in rats.

Radiation-induced esophageal injury (RIEI) is an adverse reaction of radiation therapy in patients with esophageal cancer, lung cancer and other malignant tumors. Competitive endogenous RNA (ceRNA) network is known to play a significant role in the onset and progression of many diseases, but the exact mechanism of ceRNA in RIEI has not been fully elucidated. In this study, rat esophaguses were obtained after conducting irradiation under different doses (0 Gy, 25 Gy, 35 Gy). Total RNA was extracted and mRNA, lncRNA, circRNA, and miRNA sequencing was performed. Multiple dose-dependent differentially expressed RNAs (dd-DERs), including 870 lncRNAs, 82 miRNAs, 2478 mRNAs, were obtained through the integration of differential expression analysis and dose-dependent screening (35 Gy ≥ 25 Gy > 0 Gy, or 35 Gy ≤ 25 Gy < 0 Gy). Co-expression analysis and prediction of the binding site in dd-DER were conducted and 27 lncRNAs, 20 miRNAs, and 168 mRNAs were selected to construct a ceRNA network. As the immune microenvironment is crucial for RIEI progression, we constructed an immune-related ceRNA network consisting of 11 lncRNAs, 9 miRNAs, and 9 mRNAs. The expression levels of these immune-related RNAs were verified by RT-qPCR. Immune infiltration analysis showed that the RNAs in the immune-related ceRNA network were mainly associated with the proportion of monocytes, M2 macrophages, activated NK cells, and activated CD4+ memory T cells. Drug sensitivity analysis was conducted based on the expression levels of mRNAs in the immune-related ceRNA network, and small molecule drugs with preventive and therapeutic effects on RIEI were identified. In summary, an immune-related ceRNA network associated with RIEI progression was constructed in this study. The findings provide useful information on new potential targets for the prevention and treatment of RIEI.

Associations of psychological wellbeing with COVID-19 hospitalization and mortality in adults aged 50 years or older from 25 European countries and Israel.

Background: Lower psychological wellbeing is associated with poor outcomes in a variety of diseases and healthy populations. However, no study has investigated whether psychological wellbeing is associated with the outcomes of COVID-19. This study aimed to determine whether individuals with lower psychological wellbeing are more at risk for poor outcomes of COVID-19. Methods: Data were from the Survey of Health, Aging, and Retirement in Europe (SHARE) in 2017 and SHARE's two COVID-19 surveys in June-September 2020 and June-August 2021. Psychological wellbeing was measured using the CASP-12 scale in 2017. The associations of the CASP-12 score with COVID-19 hospitalization and mortality were assessed using logistic models adjusted for age, sex, body mass index, smoking, physical activity, household income, education level, and chronic conditions. Sensitivity analyses were performed by imputing missing data or excluding cases whose diagnosis of COVID-19 was solely based on symptoms. A confirmatory analysis was conducted using data from the English Longitudinal Study of Aging (ELSA). Data analysis took place in October 2022. Results: In total, 3,886 individuals of 50 years of age or older with COVID-19 were included from 25 European countries and Israel, with 580 hospitalized (14.9%) and 100 deaths (2.6%). Compared with individuals in tertile 3 (highest) of the CASP-12 score, the adjusted odds ratios (ORs) of COVID-19 hospitalization were 1.81 (95% CI, 1.41-2.31) for those in tertile 1 (lowest) and 1.37 (95% CI, 1.07-1.75) for those in tertile 2. As for COVID-19 mortality, the adjusted ORs were 2.05 (95% CI, 1.12-3.77) for tertile 1 and 1.78 (95% CI, 0.98-3.23) for tertile 2, compared with tertile 3. The results were relatively robust to missing data or the exclusion of cases solely based on symptoms. This inverse association of the CASP-12 score with COVID-19 hospitalization risk was also observed in ELSA. Conclusion: This study shows that lower psychological wellbeing is independently associated with increased risks of COVID-19 hospitalization and mortality in European adults aged 50 years or older. Further study is needed to validate these associations in recent and future waves of the COVID-19 pandemic and other populations.

Assessing the effectiveness of intervention policies for reclaimed water reuse in China considering multi-scenario simulations.

The reclaimed water is an effective tool for water environmental management. And in China, government intervention is regarded as a powerful instrument to realize its large-scale utilization due to the public welfare and social characteristics. Therefore, the tripartite evolutionary game and multi-agent simulation system were combined to explore how intervention policies, such as price subsidies and regulation of water information disclosure, can influence the behaviors of stakeholders involved in the reclaimed water market, so as to alleviate water environment crisis. The results showed that: (1) The incentive of price subsidy shows noticeable regional differences due to different initial reclaimed water utilization rates, and the policy effect on regions with medium level utilization (25%-40%) > regions with high utilization (higher than 40%) > regions with low utilization (lower than 25%); (2) enhancing water information supervision can positively regulate the stimulation of subsidy policy in regions with low wastewater reuse; (3) the intensity of price subsidies has an inverted U-shaped relationship with the market stability in regions with high wastewater reuse; (4) diverse regulatory models on water information disclosure show various chain effects on improving wastewater reuse.

Tourism Development under Water-Energy Dual Constraints: A Case Study from Xinjiang Based on Different Emergency Scenarios.

The concept of green development requires that tourism development should be constrained by water and energy. This paper first constructed the calculation model of tourism water supply (TWS) based on water resources, economy, population, and employment. Second, according to the tourism life cycle theory, the energy-related water footprint account was built and combined with energy and water consumption, to realize water-energy dual constraints. Then, a suitability model between TWS and tourism water footprint (TWF) was established. Last, this paper predicted the growth rate of tourists in Xinjiang under the "suitability" state between TWS and TWF. Results show that in a future emergency-free setting, the average annual growth rate of tourists must be below 9.63% to maintain the "suitability" state, and in the context of emergencies damaging public health or socio-economic stability, the average annual growth rate may rise to 12.79%. In any scenario, the cap on tourist numbers in Xinjiang should be around 1.326 billion person-days in 2025, in line with the government's planning goal. Last, this paper proposed suggestions to advance the green development of tourism from three angles: strengthening water conservation policies, promoting digital tourism, and setting multiple environmental monitoring mechanisms.

Short-Term Peg-IFN α-2b Re-Treatment Induced a High Functional Cure Rate in Patients with HBsAg Recurrence after Stopping Peg-IFN α-Based Regimens.

Little is known about the treatment of patients with hepatitis B surface antigen (HBsAg) recurrence after being clinically cured by peginterferon alpha(peg-IFN-α)-based regimens. This study aimed to investigate the efficacy and safety of peg-IFNα-2b in re-treating patients with HBsAg recurrence after stopping peg-IFN α-based regimens. In this two-center, prospective observational study, 33 patients with HBsAg recurrence after stopping peg-IFN α-based regimens were enrolled and re-treated with an individualized course of peg-IFN α-2b. The hepatitis B virus (HBV) vaccine could be injected immediately after HBsAg clearance, according to patients' willingness. All patients were monitored and followed-up for 48 weeks after peg-IFN α-2b re-treatment stop. The primary endpoint was HBsAg clearance at the end of follow-up. At baseline, all patients had HBsAg levels of <10 IU/mL and undetectable HBV DNA, with the median HBsAg level of 1.66 (0.56−2.87) IU/mL. After a median of 24 (24−30) weeks of peg-IFN α-2b re-treatment, 87.9% (29/33) of the patients achieved HBsAg clearance again and 66.7% (22/33) of the patients achieved HBsAg seroconversion. At the end of follow-up, the HBsAg clearance and HBsAg seroconversion rates decreased to 78.8% (26/33) and 51.5% (17/33), respectively. Furthermore, 88.9% (16/18) of the patients with HBsAg clearance benefited from receiving the HBV vaccine therapy. Generally, both peg-IFN α-2b and HBV vaccine therapy were well tolerated. A high functional cure rate can be achieved by a short-course of peg-IFN α-2b re-treatment in patients with HBsAg recurrence after stopping peg-IFN α-based regimens. Furthermore, injecting HBV vaccine is beneficial after HBsAg clearance.

Interval two-stage stochastic programming model under uncertainty for planning emission rights trading in the Yellow River basin of China.

As a critical way to realize the optimal allocation of water environment capacity resources in the basin, emission rights trading faces multiple uncertainties, making it extremely hard and challenging to formulate appropriate decisions and plans. Therefore, this study uses interval two-stage stochastic programming (ITSP) method to model the emission rights trading process with multiple uncertainties. It can promote the secondary optimal allocation of the emission rights between the demander and the supplier after the initial allocation. Externalities caused by environmental problems are internalized through the form of emission rights trading, thereby reducing the transaction costs and promoting the coordination and integrity of water pollution control among governments in a basin. Finally, the Yellow River basin is taken as an example for case analysis. The results show that the net revenue of emission rights system in the transaction status is better than that in the non-transaction status, and the average gap of net income reaches [171.031, 193.056] billion yuan. Under different reduction policies, the average water pollutant emission reduction in transaction status is [451.15, 628.34] thousand tons, which is generally less than [516.57, 670.05] thousand tons in non-transaction status. As policies get stricter and assimilative capacity of water bodies dwindles, reduction shrinks, leading to higher risks and economic loss from being unable to meet the discharge demand. When reduction policies are relatively loose and assimilative capacity is high, emission rights trading volume peaks. At this time, the trading volume of COD reached [29.05, 40.76] thousand tons, and that of NH3-N reached [3.74, 4.31] thousand tons. All these findings will offer insights for decision-makers on how to strike a balance between economic benefits and emission rights trading plans in the Yellow River basin.

Bibliometric and visualization analysis of mesenchymal stem cells and rheumatoid arthritis (from 2012 to 2021).

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease that can lead to joint deformity and loss of function. Recent studies have shown great progress in the research of mesenchymal stem cells (MSCs) in RA. However, thus far, there have been no bibliometric or visualization analyses in this field. This bibliometric analysis provides a comprehensive overview of the general information and research hotspots of MSCs and RA. Methods: Articles relevant to MSCs and RA, published between 2012 and 2021, were searched using the Web of Science Core Collection database. Irrelevant publications were excluded from the analysis. Bibliometric and visualization analyses were conducted using VOSviewer, CiteSpace, and Scimago Graphica. Results: A total of 577 articles were analyzed. The annual number of publications increased from 2012 to 2017 and plateaued from 2017 to 2021. China and the USA had the largest number of publications. Collaboration among different organizations mainly occurs between institutes of the same country. Stem Cell Research and Therapy and Frontiers in Immunology were the most popular journals in this field. All the top 20 co-cited authors had a positive co-citation relationship. The top references indicate that MSCs can contribute to RA research and treatment mainly via immunomodulation. From 2012 to 2021, "collagen-induced arthritis," "immunomodulation," and "therapy" were some of the keywords associated with MSCs and RA, while "extracellular vesicles" showed a strong keyword burst from 2019 to 2021. Conclusion: MSCs and RA have been widely studied in different countries and institutions and by different authors over the last ten years. China and the USA had the largest number of publications. Different types of journals provide admirable sources for researchers. Some keywords, including immunomodulation and extracellular vesicles, may be hot spots in the near future. There will be more basic research and clinical translation of MSCs and RA, and substantial new treatments for RA will soon be developed.

The Performance of Serum Alpha-Fetoprotein for Detecting Early-Stage Hepatocellular Carcinoma Is Influenced by Antiviral Therapy and Serum Aspartate Aminotransferase: A Study in a Large Cohort of Hepatitis B Virus-Infected Patients.

Background and aims: Factors associated with abnormally elevated alpha-fetoprotein (AFP) in hepatitis B virus (HBV)-infected patients remain to be studied. We aimed to identify factors associated with elevated serum AFP in patients with non-hepatocellular carcinoma (HCC) and early-stage HCC and their influences on the performance of AFP for detecting early-stage HCC. Methods: This multicenter, retrospective study was conducted in 4401 patients with chronic HBV infection, including 3680 patients with non-HCC and 721 patients with early-stage HCC. Factors associated with elevated AFP were analyzed. Diagnostic performance of AFP for early-stage HCC were compared among groups through area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Results: When analyzed by multivariate logistic regression, antiviral therapy was negatively associated with elevated AFP, while hepatitis B e antigen (HBeAg) and aspartate aminotransferase (AST) > 1× upper limit of normal (ULN) were positively associated with elevated AFP both in patients with non-HCC and early-stage HCC (all p < 0.05). The AUCs of AFP for detecting early-stage HCC in patients with antiviral therapy, HBV DNA (−), alanine aminotransferase (ALT) ≤ 1× ULN, and AST ≤ 1× ULN were significantly higher compared to those in non-antiviral therapy, HBV DNA (+), ALT > 1× ULN, and AST > 1× ULN groups, respectively. When categorizing patients into AST ≤ 1× ULN and > 1× ULN, AFP achieved the highest AUCs in patients with AST ≤ 1× ULN regardless of antiviral treatment (AUCs = 0.813 and 0.806, respectively). Furthermore, there were considerable differences in the cut-off values of AFP in detecting early-stage HCC in different subgroups when applying similar sensitivity and specificity. Conclusions: Antiviral therapy and serum AST might be used to help judge and select the specific cut-off values of serum AFP for HCC surveillance in different at-risk populations.

Mesenchymal stem cells and their microenvironment.

Mesenchymal stem cells (MSCs), coming from a wide range of sources, have multi-directional differentiation ability. MSCs play vital roles in immunomodulation, hematopoiesis and tissue repair. The microenvironment of cells often refers to the intercellular matrix, other cells, cytokines and humoral components. It is also the place for cells' interaction. The stability of the microenvironment is pivotal for maintaining cell proliferation, differentiation, metabolism and functional activities. Abnormal changes in microenvironment components can interfere cell functions. In some diseases, MSCs can interact with the microenvironment and accelerate disease progression. This review will discuss the characteristics of MSCs and their microenvironment, as well as the interaction between MSCs and microenvironment in disease.

Knowledge Mapping of Exosomes in Autoimmune Diseases: A Bibliometric Analysis (2002-2021).

Background: Autoimmune diseases (AIDs) are a class of chronic disabling diseases characterized by inflammation and damage to muscles, joints, bones, and internal organs. Recent studies have shown that much progress has been made in the research of exosomes in AIDs. However, there is no bibliometric analysis in this research field. This study aims to provide a comprehensive overview of the knowledge structure and research hotspots of exosomes in AIDs through bibliometrics. Method: Publications related to exosomes in AIDs from 2002 to 2021 were searched on the web of science core collection (WoSCC) database. VOSviewers, CiteSpace and R package "bibliometrix" were used to conduct this bibliometric analysis. Results: 312 articles from 48 countries led by China and the United States were included. The number of publications related to exosomes in AIDs is increasing year by year. Central South University, Sun Yat Sen University, Tianjin Medical University and University of Pennsylvania are the main research institutions. Frontiers in immunology is the most popular journal in this field, and Journal of Immunology is the most co-cited journal. These publications come from 473 authors among which Ilias Alevizos, Qianjin Lu, Wei Wei, Jim Xiang and Ming Zhao had published the most papers and Clotilde Théry was co-cited most often. Studying the mechanism of endogenous exosomes in the occurrence and development of AIDs and the therapeutic strategy of exogenous exosomes in AIDs are the main topics in this research field. "Mesenchymal stem cells", "microRNA", "biomarkers", "immunomodulation", and "therapy" are the primary keywords of emerging research hotspots. Conclusion: This is the first bibliometric study that comprehensively summarizes the research trends and developments of exosomes in AIDs. This information identifies recent research frontiers and hot directions, which will provide a reference for scholars studying exosomes.

Invisible Effect of Virtual Water Transfer on Water Quantity Conflict in Transboundary Rivers-Taking Ili River as a Case.

Water stress in countries within a drainage basin exacerbates the water quantity conflict in transboundary rivers. However, few studies considered the invisible effect of virtual water transfer on water quantity conflict by intensifying water stress. Therefore, this study, with Ili River as the case, collects data on Virtual Water Trade (VWT) from 1990 to 2015, uses water stress index (WSI) to assess water stress values under two scenarios (with or without virtual water transfer), and takes Grey Verhulst Model to predict two scenarios water stress values respectively. Next, based on the Levenberg-Marquardt (LM) Algorithm, this study compares the water quantity conflict intensity of the two scenarios, and further explores the invisible effect of virtual water transfer on the conflicts among transboundary rivers. Results show: (1) During the study period (1990-2015), water stress in China and Kazakhstan along the banks of Ili River increased in general. (2) China was basically a net exporter of virtual water during 1990-1995, and Kazakhstan became a net exporter after 1995. (3) During 2020-2025, water conflict value of Ili River without virtual water transfer is 0.458, while the value rises to 0.622 with virtual water transfer, indicating that virtual water transfer between China and Kazakhstan has an invisible enhancement on the water quantity conflict of Ili River. (4) The intensified water quantity conflict is mainly caused by the more and more serious water stress in Kazakhstan. On such basis, it is more urgent for Kazakhstan to restructure its economy and trade.

High Follicle-Stimulating Hormone Level Associated With Risk of Rheumatoid Arthritis and Disease Activity.

Background: The prevalence of rheumatoid arthritis (RA) has significant gender and age difference. The peak age of RA is consistent with the age of menopause, which is accompanied by a sharp increase in serum follicle-stimulating hormone (FSH) level. This study aims to identify the FSH levels in female RA patients and the relationship with diseases activity. Methods: In total, 79 female RA patients and 50 age-matched controls were included in our study. Serum sex hormones levels were measured using chemiluminescence. RA patients were grouped by FSH quartile. Disease activity and inflammatory marks were analyzed among groups. Results: Lower sex hormones and higher gonadotropin were found in RA patients. Serum FSH level was significantly higher in RA patients than in the age-match controls (57.58 ± 15.94 vs. 43.11 ± 19.46, p=0.025). Even after adjusting for age (OR: 1.071; 95%CI: 1.006-1.139; p = 0.031), luteinizing hormone (LH), estradiol (E), and testosterone (T) OR: 1.066; 95%CI: 1.003-1.133; p = 0.039), the OR were still more than one. RA patients in the higher quartiles had higher ESR, DAS28-ESR and DAS28-CRP (p<0.05) than the lowest quartile. Besides, menopause age was significantly related with onset age in post-menopause RA patients (r = 0.432, p =0.008). Conclusion: High FSH appears to be a risk factor for RA and is positively associated with their disease activity. Early menopause might be an essential factor of RA.

B Cells in Rheumatoid Arthritis：Pathogenic Mechanisms and Treatment Prospects.

Rheumatoid arthritis (RA) is a common, chronic, systemic autoimmune disease, and its clinical features are the proliferation of joint synovial tissue, the formation of pannus and the destruction of cartilage. The global incidence of RA is about 1%, and it is more common in women. The basic feature of RA is the body's immune system disorders, in which autoreactive CD4+T cells, pathogenic B cells, M1 macrophages, inflammatory cytokines, chemokines and autoantibodies abnormally increase in the body of RA patients B cell depletion therapy has well proved the important role of B cells in the pathogenesis of RA, and the treatment of RA with B cells as a target has also been paid more and more attention. Although the inflammatory indicators in RA patients receiving B-cell depletion therapy have been significantly improved, the risk of infection and cancer has also increased, which suggests that we need to deplete pathogenic B cells instead of all B cells. However, at present we cannot distinguish between pathogenic B cells and protective B cells in RA patients. In this review, we explore fresh perspectives upon the roles of B cells in the occurrence, development and treatment of RA.

Calculation model for the amount of tradable water rights based on water shortage risk evaluation.

A scientific measurement of the amount of tradable water rights forms the premise for reaching an agreement in water rights trading. However, the existing measurement methods, based on water saving potential, still have problems caused by large computation workload and difficult-to-control errors. Conflicts also easily emerge between transferor and transferee during the execution of transaction agreements. This paper proposes a new method for measuring tradable water rights from the perspective of an assessment of the risk of water shortage for the transferor. The following describes the basic idea: An index system is established for the assessment of the water shortage risk of the transferor to identify water shortage risk categories. The impact of the water rights transaction volume on the transferor's water shortage risk category is analyzed under different incoming water frequencies. The transferor's water shortage risk threshold is set and a simulated annealing algorithm is designed to calculate the theoretical value of tradable water rights. The following summarizes the innovation of the proposed method: The water resource shortage risk evaluation index of the transferor is constructed based on water resource endowment, water supply, water demand, and water ecological environment of the transferor; then, a risk classification evaluation model of water resource shortage is established and a measurement method of tradable water rights is introduced. Comprehensive analysis of a case analysis of Helan County in the Ningxia Autonomous Region, China, shows that the recommended value of tradable water rights of Helan County is 40 million m3. Various methods are used to calculate the weights of evaluation indexes, which are compared to the measured results of tradable water rights; moreover, the sensitivity of the results is analyzed. The obtained results show that the use of water-saving potential to measure the amount of tradable water rights is feasible.