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Background: Pancreatic cancer stem cells (CSCs) promote pancreatic ductal adenocarcinoma (PDAC) tumorigenesis and chemoresistance. Cyclin-dependent kinase 1 (CDK1) plays an important role in tumor initiation in other tumors, but the function of CDK1 in PDAC remains unclear. Fisetin is a bioactive flavonoid with anti-tumor properties in multiple tumors, while its function in CSCs remains elusive. Results: In this study, we demonstrated that CDK1 was correlated with prognosis and was highly expressed in pancreatic cancer tissue and gemcitabine-resistant cells. Silencing CDK1 impaired tumor stemness and reduced a subset of CSCs. We found that fisetin blocked the kinase pocket domain of CDK1 and inhibited pancreatic CSC characteristics. Using acetylation proteomics analysis and phosphorylation array assay, we confirmed that fisetin reduced CDK1 expression and increased CDK1 acetylation at lysine 33 (K33), which resulted in the suppression of CDK1 phosphorylation. Silencing CDK1 or STAT3 suppressed tumor stemness properties, while overexpressing CDK1 or STAT3 showed the opposite effect. Mutation or acetylation of CDK1 at K33 weakened STAT3 phosphorylation at Y705, impairing the expression of stem-related genes and pancreatic cancer stemness. In addition, lack of histone deacetylase 3 (HDAC3), which deacetylates CDK1, contributed to weakening STAT3 phosphorylation by regulating the post-translational modification of CDK1, thereby decreasing the stemness of PDAC. Moreover, our results revealed that fisetin enhanced the effect of gemcitabine through eliminating a subpopulation of pancreatic CSCs by inhibiting the CDK1–STAT3 axis in vitro and in vivo. Conclusion: Our findings highlight the role of post-translational modifications of CDK1–STAT3 signaling in maintaining cancer stemness of PDAC, and indicated that targeting the CDK1–STAT3 axis with inhibitors such as fisetin is a potential therapeutic strategy to diminish drug resistance and eliminate PDAC. [ABSTRACT FROM AUTHOR]

Strigolactones (SLs) are plant hormones that regulate several key agronomic traits, including shoot branching, leaf senescence, and stress tolerance. The artificial regulation of SL biosynthesis and signaling has been considered as a potent strategy in regulating plant architecture and combatting the infection of parasitic weeds to help improve crop yield. DL1b is a previously reported SL receptor inhibitor molecule that significantly promotes shoot branching. Here, we synthesized 18 novel compounds based on the structure of DL1b. We performed rice tillering activity assay and selected a novel small molecule, C6, as a candidate SL receptor inhibitor. In vitro bioassays demonstrated that C6 possesses various regulatory functions as an SL inhibitor, including inhibiting germination of the root parasitic seeds Phelipanche aegyptiaca, delaying leaf senescence and promoting hypocotyl elongation of Arabidopsis. ITC analysis and molecular docking experiments further confirmed that C6 can interact with SL receptor proteins, thereby interfering with the binding of SL to its receptor. Therefore, C6 is considered a novel SL receptor inhibitor with potential applications in plant architecture control and prevention of root parasitic weed infestation. [ABSTRACT FROM AUTHOR]

Accounting for over 70% of global water withdrawals, irrigation plays a crucial role in the development of agriculture. Irrigation water requirement ( WIRR ) will be influenced by climate change due to the alteration in soil water balances, evapotranspiration, physiology and phenology under global warming. This is particularly true for rice, a high water-consuming crop. Therefore, exploring the impact of climate change on rice WIRR is of great significance for the sustainable utilization of water resources and food security. This paper aims to investigate spatially and temporally the responses of rice WIRR to climate change in the middle and lower reaches of the Yangtze River (MLRYR), which is one of the most important rice farming districts in China. With the help of the specially developed rice growing period calculation method and water balance model coupled with rice irrigation scheduling, the impacts of climate change on WIRR for early rice, late rice and single cropping rice during the historical (1961–2012) and future (2011–2100) periods were evaluated. Meanwhile, to consider the uncertainty from climate models in future projection, four GCMs under RCP2.6, RCP4.5 and RCP8.5 emission scenarios from the 5th Coupled Model Intercomparison Project (CMIP5) were employed as the input of the water balance model. The results indicate the following: (1) The days of growing period ( DGP ) for all three types of rice display shortened trends in historical and most future periods. However, in the middle region of the MLRYR, the DGP for early rice and late rice would increase by up to10 days in 2080s under RCP8.5 scenario. (2) Over the past 50 years, the WIRR significantly decreased by 1.58 and 2.10 mm yr −1 for late rice and single cropping rice, respectively. While for early rice, the WIRR only slightly decreased by 0.13 mm yr −1 . (3) Projected future WIRR would increase for all three types of rice in the whole region under RCP4.5 and RCP8.5 scenarios (up to 100 mm), but decrease for single cropping and late rice in the southeast region (up to 40 mm). The results can provide beneficial reference and comprehensive information to understand the impact of climate change on the agricultural water balance and improve the regional strategy for water resource utilization and agricultural management in the middle and lower reaches of the Yangtze River. [ABSTRACT FROM AUTHOR]

Rice growth is significantly influenced by the ongoing climatic change and subjected to water shortages. Projection on the changes of rice productivity growth and water resources utilization under future climates is of great importance for food security and water resources sustainable management. Climate model outputs in combination with physical-based crop model is an effective way to modeling the crop productivity and water consumption response, but uncertainties associated with climate models remain a major challenge. In this study, we introduce a Bayesian model averaging (BMA) method to provide the multi-model ensemble projections by merging 4 climate models under four emissions scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) from phase five of the Coupled Model Intercomparsion Project (CMIP5). The comprehensive investigation on how the rice yield, water consumption (ET), irrigation water requirement (IR), water use efficiency (WUE) and irrigation water use efficiency (IWUE) response to future climate scenarios with taking account of CO 2 concentration enrichment in three typical sites (Kunshan and Nanjing in the Yangtze River Basin, and Kaifeng in the Yellow River Basin) in rice plantation region of China was conducted by driving a well-validated rice crop model ORYAZ2000 with merging multi-model ensemble projected climate outputs. There are some obvious uncertainties for climate models projections in climatic variables with wide model spread, especially for solar radiation and wind speed. The BMA method is most competent to produce the ensemble with the lowest bias in comparison with simple model averaging (SA) method and individual climate model. In despite of the distinct response of the growth duration to future climate change for the three stations, the rice yield would be reduced significantly under the climate warming. IR would present more remarkable increase compared with the ET, especially for Nanjing and Kunshan stations, due to the decrease in precipitation during the rice growth period. The significant reduction in rice production together with enlargement in ET and IR, resulted in the generally depressed the WUE and IWUE. In addition, despite that the CO 2 fertilization effect cannot compensate the negative effect of temperature increase, the increase of CO 2 concentration can promote the overall level of yield and consequently improve the water use efficiencies of rice. [ABSTRACT FROM AUTHOR]

Abstract: Aiming to understand real-world hierarchical networks whose degree distributions are neither power law nor exponential, we construct a hybrid clique network that includes both homogeneous and inhomogeneous parts, and introduce an inhomogeneity parameter to tune the ratio between the homogeneous part and the inhomogeneous one. We perform Monte-Carlo simulations to study various properties of such a network, including the degree distribution, the average shortest-path-length, the clustering coefficient, the clustering spectrum, and the communicability. [Copyright &y& Elsevier]

In this paper, we present the empirical investigation results on the urban public transport networks (PTNs) and propose a model to understand the results obtained. We investigate some urban public traffic networks in China, which are the urban public traffic networks of Beijing, Guangzhou, Wuhan and etc. The empirical results on the big cities show that the accumulative act-degree distributions of PTNs take neither power function forms, nor exponential function forms, but they are described by a shifted power function, and the accumulative act-degree distributions of PTNs in medium-sized or small cities follow the same law. In the end, we propose a model to show a possible evolutionary mechanism for the emergence of such network. The analytic results obtained from this model are in good agreement with the empirical results. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSCs) represent a promising avenue for sustainable energy conversion, with the efficiency of these devices heavily reliant on the performance of the TiO 2 photoanode. Despite significant advancements, optimizing the photoanode material for higher efficiency remains a challenge. This study introduces a novel approach to constructing a highly efficient, multifunctional 0D/1D TiO 2 composite by simply pre-treating the TiO 2 precursor, specifically one-dimensional (1D) H-titanate nanotubes, with TiCl 4. The TiCl 4 treatment not only encourages the extensive synthesis of the one-dimensional nanostructures (i.e., nanorods) but also facilitates the in situ hydrolysis to generate small crystals that attach to the surface of the nanorods. The TiO 2 composite offers several essential benefits, including the expanded thickness, high surface area for superior dye adsorption, efficient diffuse light scattering induced by the aggregate structures, and fast charge transport within the film matrix, making it an exemplary component for DSCs. The photovoltaic performance test revealed that TiCl 4 pre-treatment increased power conversion efficiency by 36.3 %, rising from 7.63 % of untreated cells to a striking value of 10.4 %, which is a new record when N719 is used as a sensitizer and iodide-based redox shuttle employed as an electrolyte. This research provides an effective strategy for developing highly efficient photoanode material for DSCs. [Display omitted] • Functional 0D/1D TiO 2 photoanode material was innovatively prepared by simple TiCl 4 pre-treatment of the precursor. • TiCl 4 not only encourages the synthesis of the one-dimensional nanorods but also hydrolyzes in situ to form small crystals. • The resultant multifunctional TiO 2 composite exhibited the highest overall power conversion efficiency (PCE) of 10.4 %. • The strong light absorption and light scattering properties derived from the enlarged film thickness are responsible for the enhanced performance. [ABSTRACT FROM AUTHOR]

• Yield and irrigation changes in different regions are related to different reasons. • Adequate irrigation and suitable sowing dates can offset average yield losses. • Major rice cultivation regions will have narrow sowing windows at the end of this century. Warming and increasing extreme climate events are expected to reduce crop yields including rice production in China, threatening the Chinese food security. Shifting sowing date has been considered as a key adaptation strategy to sustain rice production in China. However, the extent to which it can mitigate the adverse climate change impact on yield and whether more irrigation is required remains unclear. Here, by driving ORYZA v3 with four climate models (GCMs), we analyzed the impacts of climate change on China rice yield and net irrigation water requirement (NIR) at 21 sites under a wide range of sowing date. We found that without altering sowing date, weighted average rice yield for all sites will decline 5.1, 7.3 and 15.1% in periods 2011–2040, 2041–2070 and 2071–2100, respectively. Yields losses in temperate zones are linked to increased crop development rates with higher temperatures, but in subtropical regions, the reduction is more related to the damage of heat stress during rice heading or flowering periods. NIR increases notably in all regions (up to 71%) except northeastern China, where the shortened growth duration resulted in less time to consume water. When the optimized sowing date is applied, average yield losses will be effectively compensated. To achieve these, rice-sowing date will be shifted by up to 54 days and on average 17.8–23.4 % more fresh water in future periods are needed to meet the water requirement of rice growth. We also found that, due to increasing the frequency of heat events, farmers in Chinese rice production regions (e.g., Yangtze River Basin) will have narrow sowing windows at the end of this century. This study suggests that adequate irrigation and adjusting sowing dates could mitigate the negative climate impacts on rice production in China. [ABSTRACT FROM AUTHOR]

Focuses on the Beijing Genomics Institute, a genome center in China. Reaction of the scientists to Yang Huanming, a chinese geneticist; Facilities in the institute provided by Dawning computers; Project on human genome sequencing.

Diabetic Retinopathy (DR) is a severe complication of chronic diabetes causing significant visual deterioration and may lead to blindness with delay of being treated. Exudative diabetic maculopathy, a form of macular edema where hard exudates (HE) develop, is a frequent cause of visual deterioration in DR. The detection of HE comprises a significant role in the DR diagnosis. In this paper, an automatic exudates detection method based on superpixel multi-feature extraction and patch-based deep convolutional neural network is proposed. Firstly, superpixels, regarded as candidates, are generated on each resized image using the superpixel segmentation algorithm called Simple Linear Iterative Clustering (SLIC). Then, 25 features extracted from resized images and patches are generated on each feature. Patches are subsequently used to train a deep convolutional neural network, which distinguishes the hard exudates from the background. Experiments conducted on three publicly available datasets (DiaretDB1, e-ophtha EX and IDRiD) demonstrate that our proposed methodology achieved superior HE detection when compared with current state-of-art algorithms. [ABSTRACT FROM AUTHOR]

The synchronicity of rain and heat in the summer of China's monsoon region provides sufficient water and heat resources for maize growth. However, the intra-annual distribution of precipitation and the probability of extreme precipitation have been inevitably altered by the ongoing climate change, thus affecting the matching degree between precipitation and crop water requirements (MDPCWR). Evaluating the extent to which the MDPCWR will change in the future is of great importance for food security and the sustainable management of water resources. In this study, considering that different growth stages of crops have different sensitivities to water stress, the AquaCrop model was used to calculate the MDPCWR more accurately. In addition, a cumulative distribution function-transform (CDF-t) method was used to remove the bias of 11 global climate models (GCMs) under two typical emission scenarios (SSP2-4.5 and SSP5-8.5) from phase six of the Coupled Model Intercomparison Project (CMIP6). A comprehensive investigation was conducted on how maize growth, water consumption, and the MDPCWR will respond to future climate change with CO2 concentration enrichment in the Huang–Huai–Hai (3H) region in China by driving a well-tested AquaCrop model with the bias-corrected GCMs outputs. The results indicate the following: (1) The CDF-t method can effectively remove seasonal bias, and it also performs well in eliminating the bias of extreme climate events. (2) Under the SSP2-4.5 scenario, the average maximum temperature will increase by 1.31 °C and 2.44 °C in 2021–2050 and 2051–2080, respectively. The average annual precipitation will increase up to 96.8 mm/year, but it will mainly occur in the form of heavy rain. (3) The increased maize evapotranspiration rate does not compensate for the decreased crop water requirement (up to −32 mm/year), due to a shorter growth cycle. (4) The farmland cultivation layer is not able to hold a significant amount of precipitation, due to the increased frequency of heavy rains, resulting in increased irrigation water requirements for maize over the next two periods, with the maximum value of 12 mm/year. (5) Under different scenarios, the projected future MDPCWR will decrease by 9.3–11.6% due to changes in precipitation patterns and crop water requirements, indicating that it will be more difficult for precipitation to meet the water demand of maize growing in the 3H region. The results can provide comprehensive information to understand the impact of climate change on the agricultural water balance and improve the regional strategy for water resource utilization in the 3H region. [ABSTRACT FROM AUTHOR]

Plant roots can increase soil shearing resistance directly by mechanical reinforcing. The 2D crack pattern of the surface soil near the plant were observed experimentally, and it was found that the soil cracking near the plant roots was inhibited, which may be due to the influence of the plant roots. This paper focuses on the mechanical reinforcement of soil by plant roots and investigates the development rule and formation mechanism of desiccation cracking under the influence of plant roots. A numerical model describing the process of desiccation cracking of soils in the presence of root systems, which is based on a lattice of Hooke springs model, was combined with a non-stationary random field characterized by a trend term and a random fluctuation term. The root density distribution function was introduced to describe the root distribution, and an exponential function of critical strain and root density was constructed to obtain the trend of critical strain distribution of the root systems (the root systems of a single plant). The random fluctuation term was generated by the conditional simulation technique. Minkowski densities (i.e., area density, length density and Euler number density) were adopted to quantify the crack patterns. Parameters of the model were calibrated and verified by the field experimental results, and its precision was evaluated. The effect of most input parameters (include the new parameters maximum critical strain value h c and the lateral distribution radius of RDDF r m) on the model output was analyzed. The results show that in the validation process the coefficients of determination R 2 for the Minkowski densities is between 0.749 and 0.948. Root mean square error is between 0.000 2–0.120 9. BIAS is between 0.049 5–0.139 0, and the consistency index is between 0.908 and 0.987. The model is effective in predicting the formation and development of cracks in farmland soils under the influence of the root systems. The model produces the dynamic development of the desiccation cracking network of farmland soils under the influence of the root systems. The simulation results provide ample indication of the reinforcing effect of the root systems on the soil and the limiting effect of the root systems on desiccation cracking. • The critical strain non-stationary random field of soil with roots was reproduced. • A model of soil desiccation cracking under the influence of root systems was developed. • Field experiments were conducted to validate the reliability of the proposed model. • Numerical simulations and model sensitivity analysis were conducted. [ABSTRACT FROM AUTHOR]

Hydrothermal‐based direct regeneration of spent Li‐ion battery (LIB) cathodes has garnered tremendous attention for its simplicity and scalability. However, it is heavily reliant on manual disassembly to ensure the high purity of degraded cathode powders, and the quality of regenerated materials. In reality, degraded cathodes often contain residual components of the battery, such as binders, current collectors, and graphite particles. Thorough investigation is thus required to understand the effects of these impurities on hydrothermal‐based direct regeneration. In this study, we focus on isolating the effects of aluminum (Al) scraps on the direct regeneration process. We found that Al metal can be dissolved during the hydrothermal relithiation process. Even when the cathode material contains up to 15 wt.% Al scraps, no detrimental effects were observed on the recovered structure, chemical composition, and electrochemical performance of the regenerated cathode material. The regenerated NCM cathode can achieve a capacity of 163.68 mAh/g at 0.1 C and exhibited a high‐capacity retention of 85.58 % after cycling for 200 cycles at 0.5 C. Therefore, the hydrothermal‐based regeneration method is effective in revitalizing degraded cathode materials, even in the presence of notable Al impurity content, showing great potential for industrial applications. [ABSTRACT FROM AUTHOR]

Focuses on the appointment of Xu Guanhua as head of China's Ministry of Science and Technology. Achievements and awards; Job responsibilities; Plan to promote venture capital market.

Reports the reduction of scientist workforce in the Chinese Academy of Sciences in Beijing, China. Elimination of unproductive research programs; Use of financial incentives to spur productivity; Recruitment of young scientists in addition to selecting for quality.

Reports the enactment of regulations on fossil excavation in China. Prevention of illegal digging and trafficking of fossils; Preservation of fossil sites for research purposes; Limitation on the access to fossil sites.

Reports on the return of tons of Chinese fossil after the failure to smuggle the fossils into the U.S. Composition of ichthyosaur in the shipment; Number of exquisite crinoids in the fossils; Campaign of the Chinese government to protect its cultural and scientific relics against looters.

A direct numerical method is introduced herein to investigate time-dependent Poisson's ratio of solid propellant based on a representative volume element (RVE) model. Time-dependent longitudinal and transverse strains are considered in the calculation of time-dependent Poisson's ratio under the relaxation test. The molecular dynamics (MD) packing algorithm is used to generate the high area fraction RVE model of solid propellants consisting of ammonium perchlorate (AP) particles whose radius follows lognormal distribution. In order to simulate the dewetting response of the interface between particles and matrix, the PPR model is modified and utilized during the analysis. Time-dependent Poisson's ratio is measured under different cohesive parameters, loading conditions (loading temperature, loading rate, and fixed strain), and area fraction. Numerical results reveal that time-dependent Poisson's ratio can be nonmonotonic or monotonic according to the different cohesive parameters. A concept of critical cohesive parameters is proposed to judge whether the monotonic property of time-dependent Poisson's ratio appears or not. According to the numerical analysis, the cohesive contact and the shrinkage of the bulk element are two main factors which will control the change of monotonic property. All time-dependent Poisson's ratios will increase at the beginning of the relaxation stage because the effects of cohesive contact can be ignored compared with the large shrinkage of the bulk element. However, with the increased shrinkage of the bulk element, the increased cohesive contact will defend further shrinkage at the same time. Although the shrink of the bulk element never changes its direction, the ratio of the transverse strain to longitudinal strain may decrease or keep increasing in this stage. When transverse and longitudinal strains stop to change, all time-dependent Poisson's ratios will achieve their equilibrium values. [ABSTRACT FROM AUTHOR]

To identify the value of salivary gland ultrasound (SGUS) combined with magnetic resonance imaging (MRI) and magnetic resonance sialography (MRS) in predicting the results of labial salivary gland biopsy (LSGB) in patients with suspected primary Sjögren syndrome (pSS), and construct a nomogram model to predict LSGB results. A total of 181 patients who were admitted with suspected pSS from December 2018 to April 2023 were examined and divided into a training set (n = 120) and a validation set (n = 61). Baseline data of the two groups were examined, and the value of SGUS, MRI, and MRS in predicting LSGB was analyzed. Multivariate logistic analysis was used to screen for risk factors, and nomogram prediction models were constructed using these results. In the training set, the SGUS, MRI, and MRS scores of patients in the LSGB + group were higher than those in the LSGB − group (all P < 0.001). The positive prediction value (PPV) was 91% for an SGUS score of 3, and 82% for MRI and MRS scores of 2 or more. We developed a nomogram prediction model based on SGUS, MRI, and MRS data, and it had a concordance index (C-index) of 0.94. The Hosmer–Lemeshow test (χ2 = 3.17, P = 0.92) also indicated the nomogram prediction model had good accuracy and calibration for prediction of LSGB results. A nomogram model based on SGUS, MRI, and MRS results can help rheumatologists decide whether LSGB should be performed in patients with suspected pSS. [ABSTRACT FROM AUTHOR]

[Display omitted] • A low-cost surface plasmon resonance refractive index sensor based on DVD-ROM has been studied. • Wavelength modulation is used to detect different concentrations of NaCl solution, and the sensitivity is 540 nm/RIU. • Angular modulation is also used to detect NaCl solution, and the sensitivity is 32.4 degree/RIU. • FDTD simulation results are in good agreement with the experimental results. In this paper, a low-cost surface plasmon resonance refractive index sensor based on DVD-ROM is introduced. There is a special grating structure in DVD-ROM, which can be used to excite SPR effect. We have measured the optimal resonance angle of the grating with deionized water at 28°. Wavelength modulation and angle modulation are used to detect different concentrations of sodium chloride solution. The results show that the sensitivities of the two modulation methods are 540 nm/RIU and 32.4 degree/RIU, respectively. Furthermore, we use finite difference time domain method to simulate the two methods separately. The sensitivities are 514 nm/RIU and 30.8 degree/RIU, respectively. The simulation results are in good agreement with the experimental results. Using this method to prepare the detection substrate can greatly reduce the production cost of SPR sensors. [ABSTRACT FROM AUTHOR]

Magnetic resonance (MR) images are often contaminated by Gaussian noise, an electronic noise caused by the random thermal motion of electronic components, which reduces the quality and reliability of the images. This paper puts forward a hybrid denoising algorithm for MR images based on two sparsely represented morphological components and one residual part. To begin with, decompose a noisy MR image into the cartoon, texture, and residual parts by MCA, and then each part is denoised by using Wiener filter, wavelet hard threshold, and wavelet soft threshold, respectively. Finally, stack up all the denoised subimages to obtain the denoised MR image. The experimental results show that the proposed method has significantly better performance in terms of mean square error and peak signal-to-noise ratio than each method alone. [ABSTRACT FROM AUTHOR]

Reference evapotranspiration (ET0), which is an indicator of atmospheric evaporation demand over a hypothetical reference surface, is expected to alter along with global climate change. In this study, the changes and driving forces of historical ET0 and its future projections in Xinjiang, China, were comprehensively conducted. The trend analysis revealed that regional ET0 decreased significantly at a rate of −4.1 mm/year2 during 1961–1993 and increased at a rate of 3.4 mm/year2 during 1994–2010. To explore the possible causes, the contributions of major climatic variables to the ET0 trends were derived based on the differential equation method. During 1961–1993, the decreasing trend of ET0 was primarily ascribed to the wind speed. The integrated negative effect from the decrease in wind speed (U) and increase in relative humidity (RH) was more significant than the positive effect from the increase in air temperature (T), resulting in the decrease in ET0. During 1994–2010, combined with increasing T and decreasing RH, the increase in U offset the effect of the net radiation (Rn) decrease and led to an increase in ET0. Future ET0 projections over three periods (2010–2039, 2040–2069, and 2070–2099, which are named as 2020s, 2050s, and 2080s, respectively) were conducted based on the general circulation models under two representative concentration pathways scenarios (RCP4.5 and RCP8.5). A continuous increasing trend in ET0 was demonstrated in the 21st century. The increase in ET0 will increase the irrigated water resource consumption and bring new challenge to water resource management in this area. [ABSTRACT FROM AUTHOR]

• An improved Nemerow index method for water quality assessment based on combined weighting was constructed. • Nonlinear regression models perform better in accuracy and stability, especially when the number of water quality indicators is 5. • TN, NH 4 +-N and CODMn are significantly related to the grade of surface water quality in Heilongjiang Province. Accurately evaluating surface water quality grade (WQG) is of great significance in improving the efficiency of regional water quality management. Based on seven main surface water quality indicators (including dissolved oxygen (DO), chemical oxygen demand (COD), permanganate index (CODMn), ammonia nitrogen (NH 4 +-N), fluoride (FL), total phosphorus (TP) and total nitrogen (TN)) data from 910 measuring points in Heilongjiang Province from May to August 2017, an improved Nemerow index method (IN method) based on combined weighting was constructed, and the WQG was evaluated. On this basis, the multiple linear or non-linear regression models (MLR or MNR) under different quantities of water quality indicators were established, and the prediction results were evaluated. Results show that: 1) WQG in Heilongjiang Province above grade III accounts for more than 92.6%, evaluated by the IN method; 2) The accuracy of WQG evaluated by MLR based on different quantities of water quality indicators are maintained at 77%-90% and decreases with the increase of the number of water quality indicators (N), which may be related to the selected combination of water quality indicators and key water pollutants. The accuracy is improved by 3.9%-17.4% for MNR as compared to MLR, and especially the accuracy can reach as high as 95.6% when N is 5; 3) Compare to the MLR, the MNR is less affected by the data fluctuation characteristics, and performs best when N is 5 under both the great and small data fluctuations, with an accuracy of 85% and 90%, respectively. 4) TN (0.72), NH 4 +-N (0.41), and CODMn (0.33) are significantly related to the WQG. COD is a key parameter affecting the stability and uncertainty of MLR and MNR. These results provide a simple and reliable method for accurately evaluating the surface WQG, which have important guiding significance for decision-makers and researchers in water environment protection and agricultural water fertilizer management in Heilongjiang Province. [ABSTRACT FROM AUTHOR]

Abstract Phosphorus (P) is an indispensable resource for plant growth, and under the background with P consumption increase in crop system, the agriculture and crop production may be affected through the changes of phosphorus use efficiency (PUE) due to the human interference and climate change. Therefore, it is of great importance to investigate the responses of PUE to human interference and climate change from the perspectives of historical simulation and future projection. In this study, the changes of PUE from 2001 to 2015 in the middle and lower reaches of the Yangtze River (MLRYR) of China were evaluated by means of empirical PUE-model based on the substance flow analysis (SFA) method. Their responses to future human interference and climate scenarios during 2016–2030 were investigated by driving PUE-model with three neural networks (BP, GA-BP and PSO-BP) as well as the multiple downscaling climatic data (HadGEM2-ES, BCC-CSM1.1 (m) and GFDL-ESM2M) with the help of a statistical downscaling method (SDSM). The results showed that the PUE values of the three crops (rice, wheat and maize) were 53.61%, 36.22%, and 32.56%, respectively, during the period from 2001 to 2015 and 54.11%, 38.92% and 32.78%, respectively, during the period from 2016 to 2030. Consequently, the PUE showed an increasing trend from history to future. However, the overall PUE level was not high, with a value of not more than 60%, and notably for wheat and maize, the PUE was less than 40%. Meanwhile, the precipitation affected the leaching of P because increasing in precipitation may result in a relatively high increase in the probability of low-PUE. Moreover, great potential exists for enhancing the PUE in this region, and measures to improve PUE management practices have been proposed, such as, raising the crop yield, keeping the arable area and balancing the fertilization, etc. The present study provides a beneficial reference to comprehensively understand the impacts of human interference and climate change on the PUE and further improves regional sustainable strategies for future P resource management. Highlights • Evaluating the responses of PUE to human interference and climate change from historical simulation and future projections. • Predicting the future PUE by driving PUE-model with the multiple neural networks and GCMs. • Besides the rice, the PUE values of wheat and maize were less than 40% during 2001–2030. [ABSTRACT FROM AUTHOR]

As the only connecting term between water balance and energy budget in the earth-atmospheric system, evapotranspiration ( ET ) is considered the most excellent indicator for the activity for the water and energy cycle. Under the background of global change, regional ET estimates, components partitioning as well as their spatial and temporal patterns recognition are of great importance in understanding the hydrological processes and improving water management practices. This is particularly true for the Tibetan Plateau (TP), one of most sensitive and vulnerable region in response to the environment change in the earth. In this study, with flux site observation data and monthly ET data from the monthly water balance method incorporating the terrestrial water storage changes from the Gravity Recovery and Climate Experiment satellite (GRACE) production as the multiple validations, the long-term daily ET in the TP was retrieved by a modified Penman-Monteith-Leuning (PML) model with considering evapotranspiration over snow covered area during 1982–2012. The spatial and temporal changes of partitioned three components of ET , i.e., soil evaporation ( E s ), transpiration through the stomata of plant ( E c ) and canopy interception ( E i ), were investigated in the TP. Meanwhile, how the ET components contribute to ET changes and respond to the change in environmental factors in the TP was revealed and discussed. The results indicate that E s dominates ET in most areas of the TP with the mean annual ratio of 65.7%, except southeastern regions where the vegetation coverage is high. Although regional average ET and three main components all present obvious increase trends during the past decades, high spatial heterogeneity for their trends are identified in the TP. Moreover, a mixed changing pattern can be apparently found for E s in southeastern area, E c and E i in northwestern and southeastern area. Spatially, the ET variation are mainly attributed to change in E s , followed by E c and E i . In addition, compared with evaporation-related meteorological variables, precipitation and leaf area index (LAI) provide the more dominated contributions to the changes of ET and E i in the TP, while LAI is overwhelming contribution factor for E c changes. As for E s changes, although precipitation play the important role, the effects of other factors are also non-negligible. [ABSTRACT FROM AUTHOR]

To explore the effect of tube sizes and filling process on dielectric properties of carbon nanotubes (CNTs), CNTs with various diameters and lengths were applied to synthesize Fe-filled CNTs through wet-chemical method. The permittivities of the composites of CNTs and paraffin rely on the dispersion state (agglomeration) of CNTs in polymer matrices. During the filling process, CNTs with diverse tube parameters and dispersibility experienced different structural transformations, and different iron oxides (either Fe 3 O 4 or Fe 2 O 3 ) particles (depending on the dispersibility of CNTs) were observed adhering to walls of CNTs after filling. The discrepancies along with the dispersibility of CNTs per se alter the order of the permittivity (from high to low) within samples. The smallest agglomerates and the largest permittivity were obtained for CNTs with diameters of 10–20 nm and lengths of 10–30 μm, both before and after the filling of CNTs. The role that the shape parameters played in the dielectric properties during the whole filling process was analyzed. The frequency-dependent permittivity spectrum was also examined and it obeyed Jonscher’s universal dielectric relaxation law. [ABSTRACT FROM AUTHOR]

Future changes in reference evapotranspiration (ET0) are of increasing importance in assessing the potential impacts on hydrology and water resources systems of more pronounced climate change. This study assesses the applicability of the Statistical Downscaling Model (SDSM) in projecting ET0, and investigates the seasonal and spatial patterns of future ET0 based on general circulation models (GCMs) across the Haihe River Basin. The results indicate that SDSM can downscale ET0 well in term of different basin-averaged measures for the HadCM3 and CGCM3 GCMs. HadCM3 has a much superior capability in capturing inter-annual variability compared to CGCM3 and thus is chosen as the sole model to assess the changes in future ET0. There are three homogeneous sub-regions of the Haihe River Basin: Northwest, Northeast and Southeast. Change points are detected at around 2050 and 2080 under the A2 and B2 scenarios, respectively. The Northwest is revealed to have a slight to strong increase in ET0, while the Northeast and the Southeast tend to experience a pattern change from decrease to increase in ET0. EDITOR M.C. Acreman ASSOCIATE EDITOR J. Thompson [ABSTRACT FROM AUTHOR]

[Display omitted] • Little is known about the regional and socioeconomic disparities in PM 2.5 -mortality burden in China. • We provided data of PM 2.5 -related mortality burdens for 296 Chinese cities during 2015–2019. • There were significant regional and socioeconomic disparities in PM 2.5 -related mortality burdens. • Different regions and socioeconomic groups may need different mitigation policies. Quantifying the spatial and socioeconomic variation of mortality burden attributable to particulate matters with aerodynamic diameter ≤ 2.5 µm (PM 2.5) has important implications for pollution control policy. This study aims to examine the regional and socioeconomic disparities in the mortality burden attributable to long-term exposure to ambient PM 2.5 in China. Using data of 296 cities across China from 2015 to 2019, we estimated all-cause mortality (people aged ≥ 16 years) attributable to the long-term exposure to ambient PM 2.5 above the new WHO air quality guideline (5 µg/m3). Attributed fraction (AF), attributed deaths (AD), attributed mortality rate (AMR) and total value of statistical life lost (VSL) by regional and socioeconomic levels were reported. Over the period of 2015–2019, 17.0% [95% confidence interval (CI): 7.4–25.2] of all-cause mortality were attributable to long-term exposure to ambient PM 2.5 , corresponding to 1,425.2 thousand deaths (95% CI: 622.4–2,099.6), 103.5/105 (95% CI: 44.9–153.3) AMR, and 1006.9 billion USD (95% CI: 439.8–1483.4) total VSL per year. The AMR decreased from 120.5/105 (95% CI: 52.9–176.6) to 92.7/105 (95% CI:39.9–138.5) from 2015 to 2019. The highest mortality burden was observed in the north region (annual average AF = 24.2%, 95% CI: 10.8–35.1; annual average AMR = 137.0/105, 95% CI: 60.9–198.5). The highest AD and economic loss were observed in the east region (annual average AD = 390.0 thousand persons, 95% CI: 170.3–574.6; annual total VSL = 275.6 billion USD, 95% CI: 120.3–406.0). Highest AMR was in the cities with middle level of GDP per capita (PGDP)/urbanization. The majority of the top ten cities of AF, AMR and VSL were in high and middle PGDP/urbanization regions. There were significant regional and socioeconomic disparities in PM 2.5 attributed mortality burden among Chinese cities, suggesting differential mitigation policies are required for different regions in China. [ABSTRACT FROM AUTHOR]

La 0.5 Ca 0.5 MnO 3 (LCMO) ceramic samples were synthesized by solid state reaction under different atmospheres. The transport properties were investigated under the 2-wire mode. Remarkable Electrical Pulse Induced Resistance switching (EPIR) was observed at room temperature for the samples prepared in air. However, the EPIR-effect decreases with increasing temperatures and almost disappears when temperature is more than 450 K. One finds a stronger nonlinearity of the I – V characteristic and an even larger EPIR-effect for the samples sintered in argon. Based on the analysis of the I – V characteristics and the comparison with a standard PN junction, we submit that oxygen vacancies which exist near the surface of LCMO as deep level traps, is one of the key elements for these remarkable EPIR effects. [ABSTRACT FROM AUTHOR]

• A combined subgrid-scale irrigation scheme is incorporated into WRF model. • The climatic effects of irrigation in grid and subgrid scale are evaluated. • Summer irrigation cooling effects reduce warm bias in surface air temperature. • Irrigation impacts local/remote precipitation by altering large-scale circulation. Characterizing climatic effects of agricultural irrigation is of great importance and challenging to understand the full influence of water management on the Earth's environment and hydroclimatic cycle. The investigation of the local and remote climatic responses to irrigation in the middle and lower reaches of the Yangtze River (MLRYR), a typical humid region, was previously unidentified. A novel combined subgrid-scale irrigation scheme for wheat (dynamic irrigation) and rice (fixed irrigation) was developed and incorporated into the Weather Research and Forecasting (WRF) modeling framework. The comprehensive climatic effects on energy balance, temperature, precipitation and the planetary boundary layer, were assessed by numerical experiments with irrigation off/on for ten crop growth seasons from 2007 to 2016. Both the simulated irrigation amounts of wheat and rice were generally in agreement with actual values. Surface energy and water budgets have been substantially altered by irrigation, and the magnitudes were dependent on the irrigation amounts. Irrigation increased latent heat flux and reduced sensible heat flux, especially during summer. The warm bias in the simulation without consideration of irrigation was reduced by the cooling effects of irrigation. The mean surface air temperature decreased significantly by 0.12–0.24 °C and 0.4–0.8 °C for spring and summer, respectively. Meanwhile, irrigation presented stronger cooling effects on daytime temperature than nighttime temperature, resulting in the reductions of diurnal temperature range in irrigated area. Moreover, the irrigation-induced increase of geopotential height and anomalous anticyclones led to the decreases in precipitation over the MLRYR. The changes of precipitation in remote areas were generally related to the irrigation induced large-scale circulation change. Furthermore, although the climatic effects of irrigation in grid scale were not relatively high due to the relatively low irrigation fraction, they exhibited apparently stronger in the subgrid scale, which can be used to investigate the impacts of climatic effects of irrigation on crop growth. [ABSTRACT FROM AUTHOR]

• Trends of air humidification in arid regions are evaluated by RH and e a. • RH tend to give a misleading in evaluating the trends of wetting or drying. • e a is more consistent with the precipitation changes and suitable for trending analyses of air humidification. The trend of wetting or drying is an important metric of regional and global climate change. Based on daily meteorological data during 1951–2018 from 10 stations in arid regions of North China, the performances of two indicators, relative humidity (RH) and actual water vapour pressure (e a), in evaluating the trends of air humidification are investigated. Results show that annual RH decreases by 0–0.10% yr−1 during the past decades in almost all (90%) stations, whereas annual e a presents increasing trends in 40% of stations and decreasing trends in the other 60% stations. Therefore, contrasting results are observed in the trends of air humidity reflected RH and e a. Specifically, stations getting significantly drying as indicated by RH, it is tend to getting less drying or even wetting as indicated by e a. These results suggest that it tend to give a misleading conclusion with the trends of RH as indicator in evaluating the trends of regional or global wetting or drying, due to the reduction in RH caused by the accompanying temperature rising under global warming. The other indicator e a is more consistent with the precipitation changes, and suitable for trending analyses of air humidification under such circumstance. Further researches should be done in a larger scale arid region and in different seasons, to investigate the differences in the trends of air humidification indicated by RH and e a , and discuss the response of the changes of wetting or drying to the varied meteorological factors. [ABSTRACT FROM AUTHOR]

Rice is one of the most important crops in China, contributing to approximately 28% of total cereal yield. Despite substantial production, given that rice is a high water-consuming crop, the water shortage due to the irreversible decline in available water resources on a global scale induced by undergoing climate change will pose grave challenges to rice reproductive growth and related water resources utilization. As a consequence, investigating the responses of rice productivity and water consumption to more pronounced climate changes is of great significance for water resources sustainable utilization in terms of reducing irrigation water requirements and ensuring food security. Present water footprint (WF) methods do not calculate the weighted average of each WF component at the national level when evaluating the effects of prospective climate change upon rice production. The national water footprint (NWF), i.e. taking the share of each province in the total production of crops as weighting factors, has been regarded as an effective approach to determine where each WF component is originally located. In this study, the temporal change characteristics of NWF for single-rice (SR), early-rice (ER) and late-rice (LR) in different agro-ecological zones across China during 2001–2010 were assessed for the first time. The results exhibited that NWF of rice was an estimated 304,848 million cubic meters (MCM) per year. The SR accounted for the greatest portion of NWF, followed by ER and LR. The NWF rank was SR-V > SR-I > ER-VI > SR-IV > LR-III > LR-VI > SR-II > ER-III. The blue water footprint (WF b) presents decreasing trends in most agro-ecological zones (SR-I, SR-II, SR-IV, ER-III and LR-VI), while green water footprint (WF g) exhibits increasing trends within these regions. This study provides a beneficial approach for decision-making processes aiming at better agricultural water resources management strategies to alleviate water resources scarcity and reduce food risk in the context of surging demand, which will support agricultural water resources management of China towards a more balanced direction at the national level. Unlabelled Image • The concept of 'national water footprint' (NWF) was applied in rice production for the first time in China. • The WF of single-rice and double rice (early-rice and late-rice) in eight agro-ecological zones was distinguished. • The single-rice accounted for the greatest portion of NWF, followed by early-rice and late-rice. • Compared with WF b and WF gr , the WF g plays a dominant role in the growth of rice NWF. [ABSTRACT FROM AUTHOR]

• ZnO-based nanospheres capable of releasing multiple therapeutic agents were developed. • The charge-reversal nanospheres had long blood circulation and enhanced cellular uptake. • The nanospheres released therapeutic agents in response to intracellular stimuli. • Synergistic cancer therapy with improved efficacy could be achieved using the nanospheres. 2,3-Dimethylmaleic anhydride (DMMA)-decorated zinc oxide (ZnO) nanoparticles with doxorubicin (DOX) and phenylsulfonyl furoxan (PSF) loaded were designed and prepared through a step-by-step strategy. Amino-terminated ZnO nanoparticles were synthesized, in which DOX was encapsulated by forming coordination bonding between DOX and Zn2+ ions. PSF as a NO donor was conjugated to the nanoparticles via amide bonding. Surface decoration of DMMA endowed the resultant (DOX,PSF)@ZnO-DMMA nanospheres with charge-reversal ability, as characterized by zeta potential measurements. The (DOX,PSF)@ZnO-DMMA nanospheres (an average size of ~7.9 nm) had a mildly negative surface charge and thus had a long blood circulation. The intratumoral microenvironment could reverse the surface charge of the nanospheres, which favored the cellular uptake of the nanospheres. Decomposition of ZnO occurred under acidic conditions characteristic of intracellular endosomal and lysosomal systems, leading to release of both Zn2+ ions and DOX. In the meantime, NO release from the PSF was triggered by the high concentration of GSH in the cancerous cells. The nanospheres were able to inhibit the proliferation of cancerous cells efficiently, as evidenced by in vitro cell assay and in vivo small animal experiments. The NO greatly reduced the multi-drug resistance (MDR) and increased the intracellular concentration of DOX, which killed cancerous cells in combination with the Zn2+ ions. This work has highlighted the delivery of multiple therapeutic agents in response to intracellular stimuli, which offered a new approach for rational design of nanomaterials towards synergistic cancer therapy. [ABSTRACT FROM AUTHOR]