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Drought projection is of critical significance for designing long-term drought adaptation strategies to cope with changing climate. This study presents an application of multi-class models for characterizing future droughts in the Yellow River basin (YRB). Using meteorological observations and simulations of three CMIP5 climatic models as input into VIC hydrologic model, the standardized Palmer drought index-based joint drought index (SPDI-JDI) is calculated to investigate spatiotemporal patterns and possible changes of future drought in the YRB, through an approach of bivariate modeling and analysis. It is concluded that moderate drought will be alleviated with decreased duration and severity, but extreme drought risk is likely to increase for future climate scenarios (2021–2050) relative to baseline period (1961–2000). From the perspective of bivariate analyses, the concurrence probability of drought events with extreme duration and severity might rise in the future, while increasing variability and heterogeneity of duration, severity and bivariate joint/concurrent return period would also increase the stochastic occurrence of extreme drought over time and space. These findings can provide insights into projection of climate change impacts on drought trends for the next 30 years, and help to preparations for strict control of socio-economic water consumption as well as eco-environmental protection and restoration in the YRB. [ABSTRACT FROM AUTHOR]

This work has presented gas sensors based on indium tin oxide (ITO) for the detection of SO2 and NO2. The ITO gas-sensing material was deposited by radio frequency (RF) magnetron sputtering. The properties of gas sensing could be improved by increasing the ratio of SnO2. The response characteristics of the gas sensor for detecting different concentrations of NO2 and SO2 were investigated. In the detection of NO2, the sensitivity was significantly improved by increasing the SnO2 ratio in ITO by 5%, and the response and recovery time were reduced significantly. However, the sensitivity of the sensor decreased with increasing SO2 concentration. From X-ray photoelectron spectroscopy (XPS) analysis, the gas-sensitive response mechanisms were different in the atmosphere of NO2 and SO2. The NO2 was adsorbed by ITO via physisorption but the SO2 had a chemical reaction with the ITO surface. The gas selectivity, temperature dependence, and environmental humidity of ITO-based gas sensors were systematically analyzed. The high detection sensitivity for acidic gas of the prepared sensor presented great potential for acid rain monitoring. [ABSTRACT FROM AUTHOR]

Holey layered HEO nanocrystals with surface FLP sites have been synthesized via a temperature-variable topological transition. Merits of high-entropy oxides and nanoscale effects are favored yielding a superior catalytic performance toward the transfer hydrogenation (CTH) reaction of biomass-derived carbonyl compounds at mild conditions. Mechanistic investigation indicates that the formation of active regions between FLPs provides a stronger driving force for dissociating alcohols and activating the carbonyl groups of substrates, accounting for the enhanced catalytic activity. [Display omitted] • Holey layered high entropy oxide (HEO) nanocrystals with abundant frustrated Lewis pairs (FLPs) have been synthesized. • Combination of HEO properties and nanoscale effect drives FLPs concentrations of as-obtained catalyst up to 585.4 μmol/g. • Catalysts display superior catalytic activity and cycling performance toward the CTH reaction under mild conditions. • FLPs provide stronger driving forces for dissociating alcohols and activating the carbonyl groups of substrates. • Direct hydrogen transfer dominates the catalytic reaction over holey lamellar HEO catalysts. Creating frustrated Lewis pairs (FLPs) on stable high-entropy oxides (HEOs) is a new challenge, and also an uncultivated field in catalysis. Herein, holey layered HEO spinel nanocrystals with rich FLPs were synthesized via a temperature-driven topological transition. The FLPs on the surface of HEO spinel nanocrystals are created by oxygen vacancies (Lewis acid sites) and proximal surface hydroxyls or surface lattice oxygen (Lewis base sites). Rich FLPs furnish HEO nanocrystals a superior activity towards the catalytic transfer hydrogenation reaction of biomass-derived carbonyl compounds at mild conditions. The active regions in between FLPs provide a strong driving force for dissociating alcohols and activating carbonyl groups of substrates, as evidenced by the attenuated total reflectance-infrared spectroscopy (ATR-IR) analysis, which enhances the catalytic activity. This work develops a new kind of hydrogenation catalysts and provides a perspective for creating solid FLPs. [ABSTRACT FROM AUTHOR]

Graphical abstract We prepared the catalysts through the ion-exchange of natural calcium montmorillonite with an aqueous aluminum trichloride solution. Al3+ was a good Lewis acid catalyzing the isomerization of glucose to fructose, and the partially hydrolyzed Al−OH groups acted as Brønsted acid for the dehydration of fructose to HMF, which can be extracted by THF with a high yield. Highlights • A series of Al-mont-n were prepared with ion-exchange method for conversion of carbohydrates to HMF. • The catalytic activity is dependent on the concentrations of Al3+ ion. • A high yield of HMF (80.4%) was produced from glucose. • 60.1% and 81.6% yield of HMF were obtained from the dehydration of starch and inulin, respectively. Abstract Aluminum ion-exchanged Ca-montmorillonite with different concentrations of aluminum ion were prepared and applied in the conversion of carbohydrates to 5-hydroxymethylfurfural (HMF). It was found that two types of acid sites were present in the catalyst, Lewis acid sites for isomerization of glucose and Brønsted acid sites for dehydration of fructose. With Al-mont-10 as catalyst, the yield of HMF converted from glucose was 80.4% in a biphase system (THF: NaCl solution) at 180 °C for 2.5 h. Further, the catalyst also shows excellent catalytic performance in the conversion of starch and inulin, and the yield of HMF reached 60.1% and 81.6% under identical conditions, respectively. [ABSTRACT FROM AUTHOR]

Quantitative evaluation of future climate change impacts on hydrological drought characteristics is one of important measures for implementing sustainable water resources management and effective disaster mitigation in drought-prone regions under the changing environment. In this study, a modeling system for projecting the potential future climate change impacts on hydrological droughts in the Weihe River basin (WRB) in North China is presented. This system consists of a large-scale hydrological model driven by climate outputs from three climate models (CMs) for future streamflow projections, a probabilistic model for univariate drought assessment, and a copula-based bivariate model for joint drought frequency analysis under historical and future climates. With the observed historical climate data as the inputs, the Variable Infiltration Capacity hydrological model projects an overall runoff reduction in the WRB under the Intergovernmental Panel on Climate Change A1B scenario. The univariate drought assessment found that although fewer hydrological drought events would occur under A1B scenario, drought duration and severity tend to increase remarkably. Moreover, the bivariate drought assessment reveals that future droughts in the same return period as the baseline droughts would become more serious. With these trends in the future, the hydrological drought situation in the WRB would be further deteriorated. [ABSTRACT FROM AUTHOR]

A novel series of benzophenone oxime ether derivatives with tertiary amine groups were synthesized and their herbicidal activities of 24 compounds against Oryza sativa, Sorghum sudanense, Brassica chinensis, and Amaranthus mangostanus L. were also evaluated. Most of these compounds exhibited significant inhibitory effect on root growth at 20 ppm. Based on the herbicidal activity data, computational Three-Dimensional Quantitative Structure-Activity Relationship (3D-QSAR) analysis and molecular docking were undertaken. CoMFA contour maps were generated for the design of benzophenone oxime ether analogues with enhancing activity. [ABSTRACT FROM AUTHOR]

Objective: Intratumoral hypoxia is an essential feature of hepatocellular carcinoma (HCC). Herein, we investigated the hypoxia-based heterogeneity and relevant clinical implication in HCC. Methods: Three HCC cohorts: TCGA-LIHC, LICA-FR, and LIRI-JP were retrospectively gathered. Consensus clustering analysis was utilized for hypoxia-based classification based upon transcriptome of hypoxia genes. Through LASSO algorithm, a hypoxia-relevant prognostic signature was built. Immunotherapeutic response was inferred through analyzing immune checkpoints, T cell inflamed score, TIDE score, and TMB score. RNF145 expression was measured in normoxic or hypoxic HCC cells. In RNF145-knockout cells, CCK-8, TUNEL, and scratch tests were implemented. Results: HCC patients were classified into two hypoxia subtypes, with more advanced stages and poorer prognosis in cluster2 than cluster1. The heterogeneity in tumor infiltrating immune cells and genetic mutation was found between subtypes. The hypoxia-relevant prognostic model was proposed, composed of ANLN, CBX2, DLGAP5, FBLN2, FTCD, HMOX1, IGLV1-44, IL33, LCAT, LPCAT1, MKI67, PFN2, RNF145, S100A9, and SPP1). It was predicted that high-risk patients presented worse prognosis with an independent and reliable manner. Based upon high expression of immune checkpoints (CD209, CTLA4, HAVCR2, SIRPA, TNFRSF18, TNFRSF4, and TNFRSF9), high T cell inflamed score, low TIDE score and high TMB score, high-risk patients might respond to immunotherapy. Experimental validation showed that RNF145 was upregulated in hypoxic HCC cells, RNF145 knockdown attenuated proliferation and migration, but aggravated apoptosis in HCC cells. Conclusion: Altogether, the hypoxia-based classification and prognostic signature might be useful for prognostication and guiding treatment of HCC. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer is a significant clinical issue, particularly for high Gleason score (GS) malignancy patients. Our study aimed to engineer and validate a risk model based on the profiles of high-GS PCa patients for early identification and the prediction of prognosis. Methods: We conducted differential gene expression analysis on patient samples from The Cancer Genome Atlas (TCGA) and enriched our understanding of gene functions. Using the least absolute selection and shrinkage operator (LASSO) regression, we established a risk model and validated it using an independent dataset from the International Cancer Genome Consortium (ICGC). Clinical variables were incorporated into a nomogram to predict overall survival (OS), and machine learning was used to explore the risk factor characteristics' impact on PCa prognosis. Our prognostic model was confirmed using various databases, including single-cell RNA-sequencing datasets (scRNA-seq), the Cancer Cell Line Encyclopedia (CCLE), PCa cell lines, and tumor tissues. Results: We identified 83 differentially expressed genes (DEGs). Furthermore, WASIR1, KRTAP5-1, TLX1, KIF4A, and IQGAP3 were determined to be significant risk factors for OS and progression-free survival (PFS). Based on these five risk factors, we developed a risk model and nomogram for predicting OS and PFS, with a C-index of 0.823 (95% CI, 0.766–0.881) and a 10-year area under the curve (AUC) value of 0.788 (95% CI, 0.633–0.943). Additionally, the 3-year AUC was 0.759 when validating using ICGC. KRTAP5-1 and WASIR1 were found to be the most influential prognosis factors when using the optimized machine learning model. Finally, the established model was interrelated with immune cell infiltration, and the signals were found to be differentially expressed in PCa cells when using scRNA-seq datasets and tissues. Conclusions: We engineered an original and novel prognostic model based on five gene signatures through TCGA and machine learning, providing new insights into the risk of scarification and survival prediction for PCa patients in clinical practice. [ABSTRACT FROM AUTHOR]

A stable and easily separable Fe 3 O 4 -12 nanoparticles exhibited the desired catalytic performance in the catalytic transfer hydrogenation reaction of furfural to furfuryl alcohol with 2-propanol as the hydrogen source. Moreover, a feasible flowchart from xylose to FOL was designed. Utilizing the process can realize the regeneration of biomass resources, the reuse and recycling of catalysts and solvents, and minimize the amount of solvents and pollutant emissions. • Magnetic Fe 3 O 4 -12 nanoparticles exhibited excellent catalytic performance for the CTH reaction of FAL to FOL. • A feasible flowchart from xylose to FOL was designed, which can realize the valorization of biomass resources. • Fe 3 O 4 -12 nanoparticles have good recyclability and universality for different carbonyl compounds. Magnetic Fe 3 O 4 -12 nanoparticles, an easily separable heterogeneous catalyst, exhibits high catalytic performance in the catalytic transfer hydrogenation (CTH) reaction of biomass-derived furfural (FAL) to furfuryl alcohol (FOL) with 2-propanol (2-PrOH) as the hydrogen source (90.1 % FOL yield at 160 °C for 5 h). Comparing Fe 3 O 4 nanoparticles with different particle sizes found that the smaller the nanoparticles, the larger the BET surface area, pore volume and pore diameter, resulting in more acid-base active sites through BET, SEM, TEM, NH 3 -/CO 2 -TPD and other characterizations. Moreover, a scaled-up CTH experiment of FAL and a stepwise reaction from xylose to FOL verified that the catalytic system has great industrial application prospects. A feasible flowchart of the chemical process from xylose to FOL was designed, which can realize the regeneration of biomass resources (xylose derived from corncob), the reuse and recycling of catalysts and solvents, and minimize the amount of solvents and pollutant emissions. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) remains a malignant tumor with high morbidity and mortality, accounting for approximately 1,080,000 diagnosed cases and 770,000 deaths worldwide annually. Disulfidptosis, characterized by the stress-induced abnormal accumulation of disulfide, is a recently identified form of programmed cell death. Substantial studies have demonstrated the significant influence of immune clearance on tumor progression. Therefore, we aimed to explore the intrinsic correlations between disulfidptosis and immune-related genes (IRGs) in GC, as well as the potential value of disulfidptosis-related immune genes (DRIGs) as biomarkers. Methods: This study incorporated the single-cell RNA sequencing (scRNA-seq) dataset GSE183904 and transcriptome RNA sequencing of GC from the TCGA database. Disulfidptosis-related genes (DRGs) and IRGs were derived from the representative literature on both cell disulfidptosis and immunity. The expression and distribution of DRGs were investigated at the single-cell level in different GC cell types. Pearson correlation analysis was used to identify the IRGs closely related to disulfidptosis. The prognostic signature of DRIGs was established using Cox and LASSO analyses. We then analyzed and evaluated the differences in long-term prognosis, Gene Set Enrichment Analysis (GSEA), immune infiltration, mutation profile, CD274 expression, and response to chemotherapeutic drugs between the two groups. A tissue array containing 63 paired GC specimens was used to verify the expression of 4 DRIGs and disulfidptosis regulator SLC7A11 through immunohistochemistry staining. Results: The scRNA-seq analysis found that SLC7A11, SLC3A2, RPN1 and NCKAP1 were enriched in specific cell types and closely related to immune infiltration. Four DIRGs (GLA, HIF-1α, VPS35 and CDC37) were successfully identified to establish a signature to potently predict the survival time of GC patients. Patients with high risk scores generally experienced worse prognoses and exhibited greater resistant to classical chemotherapy drugs. Furthermore, the expression of GLA, HIF-1α, VPS35, CDC37 and SLC7A11 were elevated in GC tissues. A high expression of GLA, HIF-1α, VPS35 or CDC37 was associated with more advanced clinical stage of GC and increased SLC7A11 expression. Conclusion: Current study first highlights the potential value of DRIGs as biomarkers in GC. We successfully constructed a robust model incorporating four DRIGs to accurately predict the survival time and clinicopathological characteristics of GC patients. [ABSTRACT FROM AUTHOR]

In this study, the co-combustion of coal and biomass, and the tri-combustion of coal, biomass, and oil sludge in a 130 t h−1 circulating fluidized bed (CFB) boiler are investigated via the computational particle fluid dynamics (CPFD) approach. Furthermore, the effect of biomass feeding position is also comprehensively evaluated. The results show that for the co-combustion of coal and biomass, the O2 mole fraction at the furnace outlet rises from 0.0541 to 0.0640 as the biomass blending ratio enhances from 40% to 100%, while the CO2 mole fraction reduces from 0.1357 to 0.1267. The mole fraction of NOx and SO2 at the furnace outlet decreases from 4.5867 × 10−5 to 3.9096 × 10−5 and 2.8253 × 10−4 to 4.6635 × 10−5, respectively. For the tri-combustion of three fuels, the average NOx mole fraction initially grows quickly and then declines gradually, ranging from 4.1173 × 10−5 to 4.2556 × 10−5. The mole fraction of SO2 at the furnace outlet increases from 3.5176 × 10−4 to 4.7043 × 10−4 when the ratio of oil sludge rises from 10% to 20%. The uniformity of temperature and gas components distribution is "new inlet > secondary air inlet > feed inlet". As for the three inlet positions, the mole fractions of NOx at the furnace outlet are between 3.9096 × 10−5 and 5.1537 × 10−5, while those for SO2 are between 2.5978 × 10−4 and 2.5278 × 10−4. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) is a malignant tumour, with high morbidity and mortality rates worldwide. The occurrence and development of GC is a complex process involving genetic changes in tumour cells and the influence of the surrounding tumour microenvironment (TME). Accumulative evidence shows that tumour‐associated macrophages (TAMs) play a vital role in GC, acting as plentiful and active infiltrating inflammatory cells in the TME. Main body: In this review, the different functions and mechanisms of TAMs in GC progression, including the conversion of phenotypic subtypes; promotion of tumour proliferation, invasion and migration; induction of chemoresistance; promotion of angiogenesis; modulation of immunosuppression; reprogramming of metabolism; and interaction with the microbial community are summarised. Although the role of TAMs in GC remains controversial in clinical settings, clarifying their significance in the treatment selection and prognostic prediction of GC could support optimising TAM‐centred clinicaltherapy. Conclusion: In summary, we reviewed the the phenotypic polarisation, function and molecular mechanism of TAMs and their potential applications in the treatment selection and prognostic prediction of GC. [ABSTRACT FROM AUTHOR]

The transformation of lignocellulosic biomass to platform compounds (γ-valerolactone, GVL) was a significant component in biomass development. Herein, sulfonated Zr-based metal-organic frameworks (MOF-808), a bifunctional heterogeneous catalyst with Lewis and Bronsted acid sites, were prepared to catalyze the one-pot cascade reaction of furfural (FUR) to GVL. The successful modification of the sulfonic group on MOF-808 was substantiated by multiple characterization methods. By adjusting the sulfuric acid concentration to balance the Lewis acid and Bronsted acid sites of the catalyst, S-808–2.37 was confirmed as the preferred catalyst and a 60.4 % GVL yield was achieved with 99.1 % carbon balance under the optimal conditions. Moreover, the 72.8 % GVL yield reached in the 40x magnification experiment also boded well for the catalyst's application potential. The work in this paper opened up new perspectives for the application of MOF-808 porous materials in the field of selective catalytic conversion of biomass involving multi-step reactions. [Display omitted] • Strong interaction between Zr and OH of H 3 BDC led to the formation of strong Lewis acidic/basic sites in the frameworks. • The cooperative role of strong Lewis acidic/basic sites in the S-808–2.37 contributed to the excellent catalytic performance. • This work provided a promising strategy to modulate the acid-base properties of MOF-808 without affecting its structure. [ABSTRACT FROM AUTHOR]

Climate change is a significant force influencing catchment hydrological processes, such as baseflow, i.e., the contribution of delayed pathways to streamflow in drought periods and is associated with catchment drought propagation. The Weihe River Basin is a typical arid and semi-arid catchment on the Loess Plateau in northwest China. Baseflow plays a fundamental role in the provision of water and environmental functions at the catchment scale. However, the baseflow variability in the projected climate change is not well understood. In this study, forcing meteorological data were derived from two climate scenarios (RCP4.5 and RCP8.5) of three representative general circulation models (CSIRO-Mk3-6-0, MIROC5, and FGOALSg2) in CMIP5 and then were used as inputs in the Soil and Water Assessment Tool (SWAT) hydrological model to simulate future streamflow. Finally, a well-revised baseflow separation method was implemented to estimate the baseflow to investigate long-term (historical (1960–2012) and future (2010–2054) periods) baseflow variability patterns. We found (1) that baseflow showed a decreasing trend in some simulations of future climatic conditions but not in all scenarios (p < 0.05), (2) that the contribution of baseflow to streamflow (i.e., baseflow index) amounted to approximately 45%, with a slightly increasing trend (p ≤ 0.001), and (3) an increased frequency of severe hydrological drought events in the future (2041–2053) due to baseflows much lower than current annual averages. This study benefits the scientific management of water resources in regional development and provides references for the semi-arid or water-limited catchments. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer (PCa) is known to be suitable for hypofractionated radiotherapy due to the very low α/β ratio (about 1.5–3 Gy). However, several randomized controlled trials have not shown the superiority of hypofractionated radiotherapy over conventionally fractionated radiotherapy. Besides, in vivo and in vitro experimental results show that the linear-quadratic (LQ) model may not be appropriate for hypofractionated radiotherapy, and we guess it may be due to the influence of fractionation schedules on the α/β ratio. Therefore, this study attempted to estimate the α/β ratio in different fractionation schedules and evaluate the applicability of the LQ model in hypofractionated radiotherapy. Methods: The maximum likelihood principle in mathematical statistics was used to fit the parameters: α and β values in the tumor control probability (TCP) formula derived from the LQ model. In addition, the fitting results were substituted into the original TCP formula to calculate 5-year biochemical relapse-free survival for further verification. Results: Information necessary for fitting could be extracted from a total of 23,281 PCa patients. A total of 16,442 PCa patients were grouped according to fractionation schedules. We found that, for patients who received conventionally fractionated radiotherapy, moderately hypofractionated radiotherapy, and stereotactic body radiotherapy, the average α/β ratios were 1.78 Gy (95% CI 1.59–1.98), 3.46 Gy (95% CI 3.27–3.65), and 4.24 Gy (95% CI 4.10–4.39), respectively. Hence, the calculated α/β ratios for PCa tended to become higher when the dose per fraction increased. Among all PCa patients, 14,641 could be grouped according to the risks of PCa in patients receiving radiotherapy with different fractionation schedules. The results showed that as the risk increased, the k (natural logarithm of an effective target cell number) and α values decreased, indicating that the number of effective target cells decreased and the radioresistance increased. Conclusions: The LQ model appeared to be inappropriate for high doses per fraction owing to α/β ratios tending to become higher when the dose per fraction increased. Therefore, to convert the conventionally fractionated radiation doses to equivalent high doses per fraction using the standard LQ model, a higher α/β ratio should be used for calculation. [ABSTRACT FROM AUTHOR]

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare chronic inflammatory disease with osteoarticular and cutaneous involvements as its main manifestations. Acne conglobata as a severe acne form may affect adolescent patients. Tumor necrosis factor inhibitors are usually used as a second-line therapy for refractory SAPHO syndrome and has been reported to treat acne conglobata successfully. We herein report three cases of adolescent patients with SAPHO syndrome associated with acne conglobata who were successfully treated with TNFi therapy. [ABSTRACT FROM AUTHOR]

Platelet to lymphocyte ratio (PLR) is a parameter reflecting inflammatory responses in patients with cancer. Several studies have investigated the prognostic value of PLR in patients with colorectal cancer (CRC); however, the results are controversial. Thus, we carried out a meta-analysis to evaluate the association between PLR and CRC prognostication. Relevant articles were retrieved through PubMed, Embase, and Web of Science, and pooled hazard ratio (HR) and 95% confidence interval (CI) were computed by using STATA V.12.0. Both the random-effects model and fixed-effects model were utilized. A total of 13 studies (14 cohorts) with 8,601 patients were included in the meta-analysis. Pooled HRs and 95% CIs demonstrated that increased PLR predicted poor overall survival (OS) (HR = 1.81, 95%CI:1.42–2.31, p<0.001; I2 = 65%, Ph = 0.002), disease-free survival (DFS) (HR = 1.84, 95%CI:1.22–2.76, p = 0.003; I2 = 78.3%, Ph<0.001) and recurrence-free survival (RFS) (HR = 1.84, 95%CI:1.41–2.41, p<0.001; I2 = 0, Ph = 0.686), although this was not the case for cancer-specific survival (CSS) (HR = 1.75, 95%CI:0.59–5.17, p = 0.309; I2 = 66.2%, Ph = 0.085) or time to recurrence (TTR) (HR = 1.21 95%CI:0.62–2.36, p = 0.573;I2 = 58.4%, Ph = 0.121). Subgroup analysis showed that PLR enhanced the prognostic value for OS in Caucasian patients, in small sample studies and for metastatic disease; however, this was not the case with rectal cancer. Furthermore, elevated PLR predicted reduced DFS in Caucasians and not in Asians. In conclusion, our meta-analysis showed that high PLR was a significant biomarker for poor OS, DFS, and RFS in patients with CRC; however, it had no association with CSS or TTR. [ABSTRACT FROM AUTHOR]

A case study on the evolution of hydrological drought in nonstationary environments is conducted over the Laohahe catchment in northern China. Using hydrometeorological observations during 1964–2009, meteorological and hydrological droughts are firstly analyzed with the threshold level method. Then, a comprehensive analysis on the changes within the catchment is conducted on the basis of hydrological variables and socioeconomic indices, and the whole period is divided into two parts: the undisturbed period (1964–1979) and the disturbed period (1980–2009). A separating framework is further introduced to distinguish droughts induced by different causes, that is, the naturalized drought and human-induced drought. Results showed that human activities are more inclined to play a negative role in aggravating droughts. Drought duration and deficit volume in naturalized conditions are amplified two to four times and three to eight times, respectively, when human activities are involved. For the two dry decades 1980s and 2000s, human activities have caused several consecutive drought events with rather long durations (up to 29 months). These results reflect the considerable impacts of human activities on hydrological drought, which could provide some theoretical support for local drought mitigation and water resources management. [ABSTRACT FROM AUTHOR]

Allocation and management of agricultural water resources is an emerging concern due to diminishing water supplies and increasing water demands. To achieve economic, social, and environmental goals in a specific irrigation district, decisions should be made subject to the changing water supply and water demand—the two critical random parameters in agricultural water resources management. This paper presents the foundations of a systematic framework for agricultural water resources management, including determination of distribution functions, joint probability of water supply and water demand, optimal allocation of agricultural water resources, and evaluation of various schemes according to agricultural water resources carrying capacity. The maximum entropy method is used to estimate parameters of probability distributions of water supply and demand, which is the basic for the other parts of the framework. The entropy-weight-based TOPSIS method is applied to evaluate agricultural water resources allocation schemes, because it avoids the subjectivity of weight determination and reflects the dynamic changing trend of agricultural water resources carrying capacity. A case study using an irrigation district in Northeast China is used to demonstrate the feasibility and applicability of the framework. It is found that the framework works effectively to balance multiple objectives and provides alternative schemes, considering the combinatorial variety of water supply and water demand, which are conducive to agricultural water resources planning. [ABSTRACT FROM AUTHOR]