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Clinically, chemotherapy is the mainstay in the treatment of multiple cancers. However, highly adaptable and activated survival signaling pathways of cancer cells readily emerge after long exposure to chemotherapeutics drugs, resulting in multi-drug resistance (MDR) and treatment failure. Recently, growing evidences indicate that the molecular action mechanisms of cancer MDR are closely associated with abnormalities in saccharides. In this review, saccharides affecting cancer MDR development are elaborated and analyzed in terms of aberrant aerobic glycolysis and its related enzymes, abnormal glycan structures and their associated enzymes, and glycoproteins. The reversal strategies including depletion of ATP, circumventing the original MDR pathway, activation by or inhibition of sugar-related enzymes, combination therapy with traditional cytotoxic agents, and direct modification on the sugar moiety, are ultimately proposed. It follows that abnormal saccharides have a significant effect on cancer MDR development, providing a new perspective for overcoming MDR and improving the outcome of chemotherapy.

The ecological and efficient use of saline–alkaline lands is very important worldwide. The main objective of this paper is to identify an eco-farming system suitable for saline–alkaline lands via emergetic and cosmic exergy-based ecological assessments. Three ecosystems were compared: an agriculture-free system, a local agricultural system, and a superior agricultural system. In the latter two systems, crops (winter wheat and summer maize), animal husbandry and orchards were integrated in raised fields. In the superior agricultural system, conservation tillage, intercropping, and farming-grazing system were used. After 15 years, the electrical conductivity of the soil in 0–30 cm depth was 49.2% reduced using the raised field. In 2018, the average soil electrical conductivity of the superior agricultural system was 20.1% and 14.8% lower than that of the agricultural-free system and local agricultural system, respectively. The superior agricultural system was more sustainable than both the agriculture-free system and the local agricultural system by the footprint investment per unit of footprint delivered method. The renewability and sustainability of the superior agricultural system were higher than the other systems. The economic benefit of the superior agricultural system was the highest among the three systems, which is 1.34 times higher than that of the local agricultural system. These results suggest that the superior agricultural system is better than the other two systems because it promotes the flow of materials and energy and takes advantage of the mutually beneficial effects by using conservation tillage, intercropping, and farming-grazing system. This study contributes to the theoretical foundation for policy-making in saline–alkaline regions worldwide.

Clean groundwater resources are important for the health of human. In Songyuan City, Northeast China, anthropogenic activities have led to changes in groundwater circulation, thereby depleting the aquifer system and causing water quality deterioration. To evaluate the genesis of water quality, we analyzed the hydrochemical and stable isotope compositions of shallow and deep groundwater. According to drinking water quality standards, the concentrations of Ca2+, Mg2+, and NO3- in 23.0, 30.2 and 35.4% of the samples, respectively, exceeded the acceptable ranges. The groundwater chemistry in these samples was related to geochemical processes and agricultural pollution. The hydrochemical analysis explained the reaction mechanisms in each aquifer, showing that the main source of ions in both deep and shallow groundwater is the weathering of silicate rock. In addition, the dissolution of carbonate minerals and artificial pollutants is greater in the shallow groundwater. The stable isotope results showed that long-term extraction is the cause of the diffusion of pollutants in shallow aquifers. Moreover, because most of the well-drilling techniques are backward, the aquifer structure is destroyed, and the deep groundwater is mixed with the shallow groundwater during the process of artificial extraction. The study also analyzed the conditions of the water-rock reaction. Combined with the geological background, it was found that the deep CO2 gas reservoir could provide the necessary material source for the reactions. Owing to frequent tectonic activities, deep CO2 could be discharged to the surface through the fault zone, which promotes the water-rock reaction in this area.

We address the optimal design of central tower-concentrated solar power (CSP) system combined with supercritical CO2 Brayton cycle and thermal storage under economic and environmental objectives. The economic objective is measured by the levelized cost of electricity (LCOE), and the environmental objective by the power plant’s total environmental impact potential (TEIP) considering the system’s global warming, acidification, and eutrophication emission. A multi-objective mixed-integer nonlinear programming (MINLP) model is developed that takes into account the main characteristics of CSP plant, e.g. unit operations, working fluid thermodynamics, equipment sizing, thermal storage capacity. Life cycle assessment and economic evaluation of the manufacturing, construction, operation and decommission stages of the systems are also embedded in the model. The multi-objective MINLP problem is solved by a tailored algorithm, and the resulting Pareto solutions are analyzed to identify the tradeoffs between the economic and environmental performance. The proposed approach is illustrated through a case study of a 50 MWe CSP plant. Results show that the framework is able to obtain the system’s economically-environmentally optimal design in reasonable time. A minimum LCOE of 115.82 $/MWh can be achieved for the most cost-effective design, and a minimum TEIP of 320.54 × 103 mPE90 can also be achieved for the most environmentally friendly design. A ‘balanced’ solution is identified with an LCOE of 116.89 $/MWh and TEIP of 330.29 × 103 mPE90. Numerical studies also reveal that while the Brayton cycle only accounts for a small proportion of the total investment, spending more on enhancing the efficiency of its equipment is cost-effective to improve the overall economic and environmental performance of the system.

Large amount of groundwater recharge runs in opposite direction to the scarce surface water resources in the Northern Ordos Basin, and there are two controversial viewpoints. Hydrogen and oxygen stable isotopes are employed to identify the groundwater origin. Results show that surface water and soil water are mainly recharged by groundwater instead of local precipitation. The groundwater is not recharged by local rainfall, but is inferred to have originated from the Tibetan Plateau, based on isotopic (D, 18O, 3He/4He), hydraulics, geophysical, and geological evidence. It is consistent with the viewpoint of external groundwater recharging in North China.

Temperature is widely used as a tracer for dam leakage studies. However, the temperature behaviour of complex rock masses is highly uncertain, especially during the leakage process, owing to its he...

Plenty of effective methods have been proposed for face recognition during the past decade. Although these methods differ essentially in many aspects, a common practice of them is to specifically align the facial area based on the prior knowledge of human face structure before feature extraction. In most systems, the face alignment module is implemented independently. This has actually caused difficulties in the designing and training of end-to-end face recognition models. In this paper we study the possibility of alignment learning in end-to-end face recognition, in which neither prior knowledge on facial landmarks nor artificially defined geometric transformations are required. Specifically, spatial transformer layers are inserted in front of the feature extraction layers in a Convolutional Neural Network (CNN) for face recognition. Only human identity clues are used for driving the neural network to automatically learn the most suitable geometric transformation and the most appropriate facial area for the recognition task. To ensure reproducibility, our model is trained purely on the publicly available CASIA-WebFace dataset, and is tested on the Labeled Face in the Wild (LFW) dataset. We have achieved a verification accuracy of 99.08\% which is comparable to state-of-the-art single model based methods., 9 pages, 8 figures

In this paper, we present a superpixel segmentation algorithm called linear spectral clustering (LSC), which is capable of producing superpixels with both high boundary adherence and visual compactness for natural images with low computational costs. In LSC, a normalized cuts-based formulation of image segmentation is adopted using a distance metric that measures both the color similarity and the space proximity between image pixels. However, rather than directly using the traditional eigen-based algorithm, we approximate the similarity metric through a deliberately designed kernel function such that pixel values can be explicitly mapped to a high-dimensional feature space. We then apply the conclusion that by appropriately weighting each point in this feature space, the objective functions of the weighted K-means and the normalized cuts share the same optimum points. Consequently, it is possible to optimize the cost function of the normalized cuts by iteratively applying simple K-means clustering in the proposed feature space. LSC possesses linear computational complexity and high memory efficiency, since it avoids both the decomposition of the affinity matrix and the generation of the large kernel matrix. By utilizing the underlying mathematical equivalence between the two types of seemingly different methods, LSC successfully preserves global image structures through efficient local operations. Experimental results show that LSC performs as well as or even better than the state-of-the-art superpixel segmentation algorithms in terms of several commonly used evaluation metrics in image segmentation. The applicability of LSC is further demonstrated in two related computer vision tasks.

Daihai Lake has faced severe shrinkage in recent years due to over-exploitation. Stable isotopes (D and 18O) and hydrochemistry are employed to investigate the source of lake water to better understand its recharge dynamics. Results show that, in additional to local rainfall, groundwater is also an important water supply to the lake and accounts for a greater proportion. The groundwater is not recharged by local rainfall, but originates from other sources with significantly depleted isotope values. Combined with springs and artesian wells in the basin, it is consistent with the recent discover of external groundwater recharging in Northern China.

To establish the recharge source of groundwater in the Erenhot wasteland, samples were taken from local precipitation, pumping wells, artesian wells, springs, ponds, and soil profiles in 2015 and analyzed for hydrogen and oxygen stable isotopes. Isotopic results indicate that spring water and soil water in the Erenhot wasteland are recharged by groundwater, which does not originate primarily from local precipitation. Based on isotopic signatures and geological evidences, it is hypothesized that deep circulation of surface water from the northern Tibetan Plateau is the primary source of groundwater within the study area.

Since the 20th century, scholars abroad have achieved a lot on the studies of borrowings in English. However, studies on Chinese borrowings in English are hardly involved. Scholars at home almost researched on the English borrowings in Chinese. In the light of this phenomenon, an all-round analysis on the development of Chinese borrowings in English was undertaken. Chinese borrowings were first enrolled to English in the beginning of 17th century. However, from the beginning of 17th century to the beginning of 19th century, the policy of isolation with the outside world is advocated by Qing Dynasty. The communication between China and the outside world in politics, culture and economy is rare. There are just small numbers of trades involved in teas, food, textiles and so on in Hong of some coastal cities, such as Guangzhou. So the Chinese borrowings in English in this period are limited to food, teas and textiles. From the beginning of 19th century to the beginning of 20th century, the policy of isolation with the outside world has been implemented all the time by the Qing Dynasty. Consequently, there has hardly changed in the development of Chinese borrowings in English. Since the foundation of the People’s Republic of China, Marxism and Maoism has been dominant in the whole New China as the spiritual profiles from the beginning of 20th century to the eve of Opening-up. Under the background of Red Revolution, the Chinese borrowings in English, to some extents, have increasingly developed. However, Chinese borrowings in English has been increasingly growing, especially after Opening-up, which is involved in wide fields with the improving communication in economy, politics and culture between China and the outside world. To some degrees, the increasingly strengthening influence of China on the world was reflected and the cultural soft power of China was improved. Meanwhile, some weaknesses have been pointed, which could strengthen the construction of spiritual civilization, create healthy environment for our Chinese culture introduced into world and improve the soft power of China on earth.

The Jiangnan Orogen is a collisional suture belt between the Yangtze and Cathaysia Blocks in South China, with many unanswered questions regarding its tectonic evolution. Using the basement structure of the Jiangnan Orogen, we investigate the granite and dacite exposed along the western Jiangnan Orogen and present new LA-ICP-MS zircon U-Pb ages, Hf isotopes, and whole rock geochemistry data. The results suggest that the granite plutons belong to the calc-alkaline series and are typical S-type granites. It yields a mean U-Pb age of 854 ± 2 Ma, which is determined from the core of zircon and possibly inherited from its source or wall rocks. The initial emplacement age of granite may be 826-805 Ma, whereas the dacites yield an age of 805 ± 1.6 Ma and belong to the shoshonite series. The initial Hf-isotope ratios (176Hf/177Hf) in the granite sample are mostly negative eHf(t), with a few of positive value with 1.38–1.6 Ga TDM and 1.67–2.06 Ga TDM2, whereas the dacite samples have mostly positive eHf(t), with a 0.78–1.6 Ga TDM and 0.83–2.2 Ga TDM2t. A comparison of the eHf(t) and TDM2t with the corresponding intruded strata, helps illustrate the origin of the magma and the finals stages ofcollision. Based on our results, we conclude that the western Jiangnan Orogen was a back-arc foreland basin that developed on the margin of the Yangtze continent and collided with the Cathaysia Block, forming a continent-arc-continent accretionary orogeny between 860 and 800 Ma.

Background Growing evidences indicate that circular RNAs (circRNAs) play an important role in the regulation of biological behavior of tumor. We aim to explore the role of circRNA in glioma and elucidate how circRNA acts. Methods Real-time PCR was used to examine the expression of circPTN in glioma tissues and normal brain tissues (NBT). Assays of dual- luciferase reporter system, biotin label RNA pull-down and FISH were used to determine that circPTN could sponge miR-145-5p and miR-330-5p. Tumor sphere formation assay was performed to determine self- renewal of glioma stem cell (GSCs). Cell counting Kit-8 (CCK8), EdU assay and flow cytometry were used to investigate proliferation and cell cycle. Intracranial xenograft was established to determine how circPTN impacts in vivo. Tumor sphere formation assay was performed to determine self- renewal of glioma stem cell (GSCs). Results We demonstrated circPTN was significantly higher expression in glioma tissues and glioma cell lines, compared with NBT and HEB (human astrocyte). In gain- and loss-of-function experiments, circPTN significantly promoted glioma growth in vitro and in vivo. Furthermore, we performed dual-luciferase reporter assays and RNA pull-down assays to verify that circPTN acts through sponging miR-145-5p and miR-330-5p. Increasing expression of circPTN rescued the inhibition of proliferation and downregulation of SOX9/ITGA5 in glioma cells by miR-145-5p/miR-330-5p. In addition, we found that circPTN promoted self-renewal and increased the expression of stemness markers (Nestin, CD133, SOX9, and SOX2) via sponging miR-145-5p. Moreover, this regulation was disappeared when circPTN binding sites in miR-145-5p were mutated. Conclusions Our results suggest that circPTN is an oncogenic factor that acts by sponging miR-145-5p/miR-330-5p in glioma.

Semantic attention has long been adopted to image captioning models to enhance the image captioning performances. The models pre-trained for attribute recognition are utilized to generate image attributes in image captioning. Generally, these models are not jointly trained with image captioning models. In this paper, we propose attribute refinement network, which incorporates attribute recognition with image captioning to boost the performance on both tasks. We model the correlation between attributes with the semantic information from image captioning to improve the recognition accuracy. In turn, better attribute recognition results effectively enhance image captioning performance. Our model achieves CIDEr-D/SPICE scores of 115.1 and 20.9 respectively on the MS COCO test set, comprehensively yields improvement over all compared methods.

Human parsing has recently attracted considerable interests due to its wide application potentials. However, developing an accurate human parsing system is still a challenge for researchers. In this paper, we demonstrate that global information are critical for accurate prediction by applying a non-local operation for effectively extracting global information. Meanwhile several training data refinement methodologies are proposed to further boost the performance. Benefiting from all the approaches, the proposed single human parsing model NLGINet achieves the state-of-the-art segmentation accuracy on two human parsing benchmark datasets LIP and Pascal-Person-Parts.

Based on the movement analysis of burden in charging, a mathematical model of bell-less burden distribution is established to study the burden distribution in the furnace. The mathematical model consists of three sub-models: the material trajectory model, burden profile model, and burden descent model. The novel fitting formula that chute inclination angle and ratio of mixed ore affect the inner angle and outer angle of repose is proposed. The influence of pellet and sinter shapes on the inner angle and outer angle of repose of the ore is considered by introducing a correction coefficient. The modified fitting relation is applied to the mathematical model for bell-less blast furnace to analyze the influence of the proportion of pellet on the surface shape and radial distribution of ore–coke ratio under the same burden matrix. The influence rule of mixed ore ratio on burden distribution is obtained, which provides basis for adjusting the upper part of blast furnace.

Table S1. Sequences of si-circPTN, primers and probes for FISH. (DOCX 19 kb)

California is facing water crisis, especially with significant depletion of groundwater resources. Recently, Jasechko proposed a method for estimation of the fossil groundwater mass fraction (F-fossil) based on C-14 (Jasechko's method), but it did not account for the endogenic carbon source. Based on carbon isotope and water chemistry balance, the ratio of the concentration of endogenic carbon to dissolved inorganic carbon (C-endogenic/DIC ratio) in groundwater is quantified, and the Jasechko's method is modified with consideration of endogenic carbon input. Both Jasechko's and modified methods are applied to estimate the F-fossil across California, where endogenic CO2 degases at many locations. The results show that, averagely, the C-endogenic takes up similar to 23.4% of DIC in groundwater samples, with similar to 19.4% of samples owning C-endogenic/DIC ratio exceeding 50%. About 8.4% of groundwater samples show smaller F-fossil calculated by the modified than Jasechko's method, with the mean value of F-fossil deceasing by similar to 3.1%. This indicates obvious mixture of endogenic carbon in DIC of groundwater across California, but it has little influence on the estimation of F-fossil. Even though, the process-based modified method is more objective than the empirically Jasechko's method. Groundwater samples with high C-endogenic/DIC ratio and mass fraction difference of fossil groundwater between the two methods are mainly located in the Mojave Desert with wide distribution of main active faults. The average F-fossil calculated by both methods are similar to 70%, demonstrating the dominance of fossil groundwater across California. These results are beneficial to better understand the C-14 dating method and the groundwater resources in California.

With the increasing impact of drought and anthropogenic c activities, middle and high latitude lakes are increasingly facing exacerbated eutrophication. The sister lakes Hulun Lake and Buir Lake, the former located in the Hulunbuir Grassland in northeast China and the latter shared by China and Mongolia, have been exposed to outbreaks of harmful algal blooms (HABs) of varying degrees. In this study, multi-source remote sensing technologies were utilized to explore the essential factors causing HAB occurrences in the Hulun Basin. First, a simplified adjusted floating algae index (AFAI) algorithm was applied to invert the HAB sequence from 1984 to 2019. The results show that large-scale HABs were detected in both lakes on or close to the same days in 1984, 1999, and 2013. From a long-term perspective, the HAB events of Hulun Lake are more serious and intractable than those of Buir Lake in terms of outbreak frequency, duration, and scale. Furthermore, the effects of meteorological and hydrological conditions were evaluated quantitatively. In situ sampling of the two lakes highlights the limiting effect of nutrients on the algae flooding in Buir Lake with perennial outflow. In contrast, Hulun Lake turned into an internal flow lake without outlets from 2000 to 2012 and the decreasing water volume stimulated the accumulation of total nitrogen (TN) and phosphorus (TP), with averages of 2.36 and 0.21 mg/L, respectively. Analysis of the comprehensive driving factors demonstrates that the level of exogenous nutrients caused a difference in the severity of the HAB event between the sister lakes, which are largely determined by drought and eco-unfriendly anthropogenic activities. Our work emphasizes the pivotal role of substantial increases of nutrient loads and stricter regulations are necessary to curb further deterioration of this situation.

Stable isotopes 2H and 18O of fog drip water, lake water, soil profiles, and vegetation leaves in Junshan wetland of East Dongting Lake, China, were investigated to estimate the contribution of fog drip water to wetland vegetation. Because of its recycled terrestrial meteoric water source, fog drip water is characterized by isotopic compositions that plot above the local meteoric water line (LMWL). Lake water undergoes intense evaporation owing to its low water volume and long residence time. The isotopic compositions of soil water suggest that it is recharged by both recent rainfall and fog drip water. A binary mixing model shows that approximately 16% of unsaturated soil water originates from continuous recharge by fog drip water, reaching 31% in surface soil where the vegetation roots are mainly distributed. Inspired by the literatures on acidification of intercepted clouds and fog as the major factor in forest die-back in Europe, the findings in this study inform future investigations into the relationships between fog water deposition and wetland degradation especially in heavily industrialized foggy areas.

The Shi-Hang Belt is a Mesozoic tectonic zone and has always been regarded as the boundary between the Yangtze and Cathaysia blocks. It occupies a key tectonic location and attracts considerable attention due to its dynamic formation mechanism. However, its Cenozoic dynamic process is poorly constrained. The Cenozoic activation of the Shi-Hang Belt, as well as its cooling and exhumation, aids in dating the onset time of the formation of the mountain ranges and reveals the deformation process of the South China Block. To uncover the history of its Cenozoic cooling and denudation, apatite fission-track (AFT) thermochronology was applied to batholiths and strata spread across the Shi-Hang Belt in the Hunan Province. Twenty-three samples are dated with ages ranging from 23.6 ± 1.5 to 45.8 ± 3.0 Ma. Except for two older ages (42.1 ± 2.6 and 45.8 ± 3.0 Ma), the other ages range from 23 to 36 Ma with less variation on both sides of the Chenzhou–Linwu fault. The thermochronological modelling of 15 measure...

In this study, a multiple tracer analysis was carried out to investigate the leakage pathway of the Xixiayuan dam, located on the Yellow river in China. Composite geomembrane and a concrete cutoff wall are used jointly to control seepage. Filling of the reservoir began on May 30, 2007, with water level rising to 133.6 m ASL (Above Sea Level) on October 2, 2007. Thereafter, the water level fluctuated between 133.0 m ASL and 133.6 m ASL until a leakage point emerged on October 15, 2007. From October 16 to 18, 2007, two other water leakage points were found emerging from the top of a drainage channel located at the downstream toe of the left earth rockfill dam. To determine the possible leakage pathways, 10 additional investigation boreholes were installed. Single-borehole artificial isotope dilution tests were carried out to quantify the vertical and horizontal flow velocities in boreholes at high and low reservoir water levels. Temperatures and water levels were measured in boreholes, reservoir water, and leakage points. An interconnection test using salty water tracer was performed between borehole and leakage point. As a result of these studies, the possible seepage location was identified to be near boreholes ZZ5 and ZZ6. Excavation and inspection at the estimated seepage location confirms the presence of a construction defect.

In arid and semiarid areas, low rainfall and high evaporation make groundwater the main source of soil water in the vadose zone. In order to understand the upward migration rate of soil water and the mechanisms of moisture migration in the vadose zone, evaporation experiments in sand and loess soils were conducted. The evaporation and imbibition of the soil columns were measured in order to analyze the upward migration rate of soil water. Hydrochemical and isotopic methods were applied to investigate the microscopic mechanisms of water movement in the vadose zone. The results show that soil columns with higher loess contents have higher imbibition and evaporation rates. Obvious evaporation occurs only after soil water has reached the surface layer of the soil column, and the evaporation rate is related to soil composition. Salt migrates in the same direction as that of water movement and accumulates after the evaporation of water. The greater the evaporation, the greater the salt accumulation. Only strong hydraulic connections between soil water support the diffusion of salt from areas of higher concentration to those of lower concentration. Before liquid water reaches the surface layer, there are two regions of unsaturated soil. In the lower column, soil water moves in the form of liquid water and hydraulic connections are strong. In the upper column, water vapor from the lower column diffuse in soil pore spaces, and some are absorbed or condensed in the soil.

Artesian wells and lakes are found in the hinterland of the Hopq Desert, China. Analysis of soil profiles has revealed that the local vadose zone is always in a state of water deficit because of strong evaporation, and precipitation cannot infiltrate into the groundwater. This research indicated that soil water and surface water are recharged by groundwater and that the groundwater is recharged via an external source. Analyses of the stable isotopes in precipitation and of the water budget suggested that surface water in the Qiangtang Basin on the Tibetan Plateau might correspond to the groundwater in the Hopq Desert.

Brushless doubly fed induction generators (BDFIGs) are promising alternatives to doubly fed induction generators due to high reliability and low maintenance cost for the absence of brushes and slip rings. As a typical application in offshore wind energy generation, a feedforward method is applied to the grid-voltage oriented vector control to make the active and reactive power decoupled. Another challenge in practice is how to meet the demanding requirements of grid codes. The dynamic behavior of BDFIG is analyzed in detail under unbalanced grid conditions with the proposal of four different targets. To deal with these issues, an improved vector control strategy based on the proportional-integral resonant controller (PI + R) in a single synchronous reference frame is developed. The stability and robustness of the proposed control scheme under parameters uncertainties and variations are discussed as well. The advantage of this control strategy is that it is simple and fast in transient response. The effectiveness of the proposed control strategy is validated by the experiment results of a 3-kW prototype machine.

The Alxa Desert in north-central China has a unique landscape that contains hundreds of lakes and the highest sand dunes in the world. To date, however, the explanation of the water source in this desert is still controversial. In this paper, continuous hydrometeorological observations, including precipitation, evaporation, water level and temperature, in the interior of the Alxa Desert are presented and the water balance of a typical desert lake is calculated. The moisture, Cl − concentration, δ 2 H and δ 18 O of several sand profiles, the hydrogeochemical characteristics of some lakes and groundwater, and the elemental composition of some travertine samples are analyzed to investigate the rainfall percolation and groundwater recharge. The results showed that local precipitation is not the major replenishment source of the lakes and groundwater in the Alxa Desert. It is supposed that the groundwater from deep strata in the adjacent fracture zone might recharge the desert lake group from the southeast along an altitudinal gradient.

Groundwater is the main source of drinking water for residents of the Songnen Plain, and its high fluoride content affects the health of residents. Previous studies have revealed hydro-geological conditions for fluoride enrichment, but relatively little research has been done on hydrogeochemical processes. In this study, the analysis of the stable isotopes and the water chemistry of 444 groundwater samples showed that high-fluoride groundwater has the characteristics of high Na+ and high HCO3−, and the pH is neutral to weakly alkaline. Geochemical analysis revealed that fluorite in the sedimentary layer is the main source of fluoride in the groundwater. In addition, the concentration of F− is related to the alkaline environment, human activity, fluorite solubility, cation exchange, and silicate weathering. The relationship between δ18O and F− indicates that evaporation does not have a notable effect on F− enrichment. Hydrogen and oxygen isotope analysis, combined with previous survey results on the groundwater circulation in Songyuan, show that the increase of the F− concentration in the Quaternary confined aquifer is either related to submerged overflow or to the destruction of the aquifer structure, due to artificial abstraction, indicating the effects of water cycle on the diffusion of F− between different aquifers.

This paper addresses the simultaneous optimization of a novel combined supercritical CO2 Brayton cycle-organic Rankine cycle integrated with molten salt solar power tower plant. The supercritical CO2 Brayton cycle adopts a two-stage compression intercooling design. The organic Rankine cycle is added as a bottoming cycle to recover the waste heat of the Brayton cycle to generate extra power. Due to its complexity, the integrated system involves many degrees of freedom, which make it challenging to optimize using metaheuristic methods. To tackle this issue, we develop an equation-based model that simultaneously optimizes stream thermodynamic properties and flowsheet mass/heat equilibrium of the integrated system. The problem is formulated as a nonlinear programming model, and a tailored two-step solution strategy is developed to improve its solution efficiency. Several numerical studies are carried out to demonstrate the effectiveness of the proposed optimization method, as well as the efficiency of the integrated system. Solution time of the model is less than 224 CPU seconds. Results show that the method obtains an increase up to 3.6% in thermal efficiency compared with literature results; the optimal intercooling design increases net power output by 2.7% comparing with recompression cycle; the recompression cycle-organic Rankine cycle design obtains a 3.5% increase; and the combined intercooling cycle-organic Rankine cycle design achieves a total 4.4% increase.

The Large Optical/infrared Telescope (LOT) is a ground-based 12 m diameter optical/infrared telescope which is proposed to be built in the western part of China in the next decade. Based on satellite remote sensing data, along with geographical, logistical and political considerations, three candidate sites were chosen for ground-based astronomical performance monitoring. These sites include: Ali in Tibet, Daocheng in Sichuan and Muztagh-ata in Xinjiang. Up until now, all three sites have continuously collected data for two years. In this paper, we will introduce this site testing campaign, and present its monitoring results obtained during the period between March 2017 and March 2019.

The hydrogen (δD) and oxygen (δ18O) isotopic compositions in the water molecule have been widely used as tracers for studying the global water cycle. In 1961, the Global Network of Isotopes in Precipitation (GNIP) was established to measure D and 18O isotopes contents in precipitation around the world. However, on the spatial scale, the long-term arithmetic and/or long-term precipitation weighted mean δD and δ18O have been most commonly used to interpret the GNIP isotope data for over sixty years. The spatial distributions of mean δD and δ18O depict well the regional moisture transport, but they vary predominantly with latitude on the global scale, especially over continental areas, obscuring the continental and circulation effects. We developed a new method of using the entropy concept to reanalyze precipitation isotopic compositions data from GNIP. Calculated entropies of isotopic compositions in precipitation at GNIP stations around the world strongly correlate in a linear fashion with a slope coefficient close to unity. The spatial distributions of both isotopic compositions entropies generally reveal oceanic sources of water vapor and main moisture transport pathways from oceans to continents globally, with different patterns between summer and winter seasons. Although these results have mostly been reported in previous studies, they provide the verification of this new analysis method. The entropy method proposed here is expected to provide a new tool for data interpretation of water isotopic compositions, with implications for tracing global hydrological processes.

The timed up-and-go (TUG) test has been widely accepted as a standard assessment for measuring the basic functional mobility of patients with Parkinson’s disease. Several basic mobility sub-tasks “Sit,” “Sit-to-Stand,” “Walk,” “Turn,” “Walk-Back,” and “Sit-Back” are included in a TUG test. It has been shown that the time costs of these sub-tasks are useful clinical parameters for the assessment of Parkinson’s disease. Several automatic methods have been proposed to segment and time these sub-tasks in a TUG test. However, these methods usually require either well-controlled environments for the TUG video recording or information from special devices, such as wearable inertial sensors, ambient sensors, or depth cameras. In this paper, an automatic TUG sub-task segmentation method using video-based activity classification is proposed and validated in a study with 24 Parkinson’s disease patients. Videos used in this paper are recorded in semi-controlled environments with various backgrounds. The state-of-the-art deep learning-base 2-D human pose estimation technologies are used for feature extraction. A support vector machine and a long short-term memory network are then used for the activity classification and the subtask segmentation. Our method can be used to automatically acquire clinical parameters for the assessment of Parkinson’s disease using TUG videos-only, leading to the possibility of remote monitoring of the patients’ condition.

The effects of different online product presentations (OPP) on customers' purchase intention are explored in this paper. Two kinds of online product presentations are mentioned to influence purchase intention, including interaction presentation design and non-interaction presentation design. Besides, engagement is introduced to explore the direct effects of OPP on attracting customers to purchase specific products. And enticement is introduced to evaluate whether the OPP would drive customers to physical stores to experience the physical product and make a purchase decision. Results of a study of 255 participants show that a higher interaction product presentation design would lead to higher customers' engagement and enticement, and both of them are positively associated with purchase intention. Besides, this study provides support for the hypothesis that price sensitivity plays the mediating role between the relationship of engagement and enticement.

Precipitation isotope data were used to determine the origin of groundwater in the Badain Jaran Desert (BJD) in the study of Wu et al. (2017). Both precipitation and its isotopic composition vary seasonally, so arithmetic averages of precipitation isotope values poorly represent the isotope composition of meteoric water. Their finding that the BJD groundwater is recharged by modern meteoric water from local areas including the southeastern adjacent mountains was based on arithmetic averaging. However, this conclusion is not supported by the corrected mean precipitation isotope values, which are weighted by the precipitation rate. Indeed, the available isotopic evidence shows that modern precipitation on the Qilian Mountains is more likely to be the main source of the groundwater and lake water in the BJD, as found by Chen et al. (2004).

Glioma is a devastating cancer with a dismal prognosis and there is an urgent need to discover novel glioma-specific antigens for glioma therapy. Previous studies have identified CD163-positive tumour cells in certain solid tumours, but CD163 expression in glioma remains unknown. In this study, via an analysis of public datasets, we demonstrated that CD163 overexpression in glioma specimens correlated with an unfavourable patient prognosis. CD163 expression was increased in glioma cells, especially primary glioma cells. The loss of CD163 expression inhibited both cell cycle progression and the proliferation of glioblastoma multiforme (GBM) cell lines and primary glioma cells. CD163 interacted directly with casein kinase 2 (CK2) and CD163 silencing reduced AKT/GSK3β/β-catenin/cyclin D1 pathway activity via CK2. Moreover, CD163 was upregulated in CD133-positive glioma stem cells (GSCs), and CD163 downregulation decreased the expression of GSC markers, including CD133, ALDH1A1, NANOG and OCT4. The knockdown of CD163 impaired GSC stemness by inhibiting the CK2/AKT/GSK3β/β-catenin pathway. Finally, a CD163 antibody successfully induced complement-dependent cytotoxicity against glioma cells. Our findings indicate that CD163 contributes to gliomagenesis via CK2 and provides preclinical evidence that CD163 and the CD163 pathway might serve as a therapeutic target for glioma.

A satellite image time series (SITS) contains a significant amount of temporal information. By analysing this type of data, the pattern of the changes in the object of concern can be explored. The natural change in the Earth’s surface is relatively slow and exhibits a pronounced pattern. Some natural events (for example, fires, floods, plant diseases, and insect pests) and human activities (for example, deforestation and urbanisation) will disturb this pattern and cause a relatively profound change on the Earth’s surface. These events are usually referred to as disturbances. However, disturbances in ecosystems are not easy to detect from SITS data, because SITS contain combined information on disturbances, phenological variations and noise in remote sensing data. In this paper, a novel framework is proposed for online disturbance detection from SITS. The framework is based on long short-term memory (LSTM) networks. First, LSTM networks are trained by historical SITS. The trained LSTM networks are then used to predict new time series data. Last, the predicted data are compared with real data, and the noticeable deviations reveal disturbances. Experimental results using 16-day compositions of the moderate resolution imaging spectroradiometer (MOD13Q1) illustrate the effectiveness and stability of the proposed approach for online disturbance detection.

The Chishui forest region in the southwest of China has a unique landscape with thousands of waterfalls that produce a significant water yield even during and after a long dry period. However, the sources of water for sustaining the waterfall landscape are poorly understood. We use stable isotopes 2H and 18O to trace water in surface runoff and determine the runoff generation mechanism in the catchments. Located on the pathway of water vapor from the neighboring Sichuan Basin, the area is covered by a thick forest canopy above sandstone strata. The local conditions combine to create a microclimate that favors formation of fogs at relatively high frequencies. It was found that frequent fogs in this region act as a key water supplier for waterfalls and play an important role in the regional hydrology. During the dry period starting from October, waterfalls are mainly sustained by baseflow, 8–31 % of which comes from frequent fog water recharge. The waterfall landscape in the Chishui forest represents a unique characteristic of the regional hydrological system in close connection with its geographical location, geology, climatology and ecology.

We propose a large-margin Gaussian Mixture (L-GM) loss for deep neural networks in classification tasks. Different from the softmax cross-entropy loss, our proposal is established on the assumption that the deep features of the training set follow a Gaussian Mixture distribution. By involving a classification margin and a likelihood regularization, the L-GM loss facilitates both a high classification performance and an accurate modeling of the training feature distribution. As such, the L-GM loss is superior to the softmax loss and its major variants in the sense that besides classification, it can be readily used to distinguish abnormal inputs, such as the adversarial examples, based on their features' likelihood to the training feature distribution. Extensive experiments on various recognition benchmarks like MNIST, CIFAR, ImageNet and LFW, as well as on adversarial examples demonstrate the effectiveness of our proposal., Comment: Accepted to CVPR 2018 as spotlight

Deep reinforcement learning (DRL) has been showing its strong power in various decision making and controlling problems, e.g. Atari games and the game of Go. It is inspiring to see DRL agents to outperform even human masters. However, DRL algorithms require a large amount of calculation and exploration, making DRL agents hard to train, especially in problems with large state and action spaces. Also, most DRL algorithms are very sensitive to hyper parameters. To solve these problems, we propose A3COE, a new algorithm combining the A3C algorithm with online expert supervision. We applied it on mini-games of the famous real-time-strategy game StarCraft II. Results show that this algorithm greatly improved the agent’s performance with fewer training steps while acquiring more stable training processes with a greater range of hyper parameters. We also proved that this algorithm works even better with curriculum learning.

Median filtering detection has recently drawn much attention in image editing and image anti-forensic techniques. Current image median filtering forensics algorithms mainly extract features manually. To deal with the challenge of detecting median filtering from small-size and compressed image blocks, by taking into account of the properties of median filtering, we propose a median filtering detection method based on convolutional neural networks (CNNs), which can automatically learn and obtain features directly from the image. To our best knowledge, this is the first work of applying CNNs in median filtering image forensics. Unlike conventional CNN models, the first layer of our CNN framework is a filter layer that accepts an image as the input and outputs its median filtering residual (MFR). Then, via alternating convolutional layers and pooling layers to learn hierarchical representations, we obtain multiple features for further classification. We test the proposed method on several experiments. The results show that the proposed method achieves significant performance improvements, especially in the cut-and-paste forgery detection.

Piping, or backward erosion, resulting in tunneling under an embankment or foundation, is an important phenomenon that can lead to the failure of the embankment or foundation. We have experimentally investigated the erosion mechanism of this piping phenomenon using a laboratory-scale model. We discovered two types of coupled erosion in the evolution of piping through an analysis of the grain size distribution of the eroded mass. Overall, grain sizes in the eroded mass ranged from 0.1 to 0.5 mm. The 0.1-0.25 mm grains were found to dominate when the erosion was induced by stress release, whereas in the case of clogging, the dominant grain sizes were 0.25-0.5 mm. The first form of erosion caused the tunnel to advance upstream, whereas the second increased the depth of the tunnel; otherwise, the two types of erosion were coupled. Furthermore, the eroded mass throughout the evolution of piping was non-uniform and intermittent.

Cut-off walls have been widely used to control seepage in dams and their foundations for over 100 years. The soil at the bottom of a cut-off wall is usually under complex stress and composed of various particles with different contents. In this study, the effects of the stress state and grain composition on the evolution of internal erosion were investigated in sandy gravel foundations containing a suspended cut-off wall. The following observations were made based on the experimental results: (1) The fine-particle content of the soil sample considerably influences the evolution of internal erosion. For high fine-particle content, particles are likely to clog under the downward flow; however, for low fine-particle content, the downward flow assists the migration of fine particles. (2) Deviatoric stress considerably influences the soil structure. The soil sample is compressed under low deviatoric stress; however, it undergoes dilatancy under high deviatoric stress. (3) Dilatant behavior is also controlled by confining stress. The higher the confining stress, the higher is the deviatoric stress applied on the soil sample, which produces dilatancy, and the smaller is the volumetric expansion. The obtained results will enhance the understanding of the progression mechanism of internal erosion around suspended cut-off walls.

Two water sampling campaigns were carried out in April and August 2012 to investigate the spatial and temporal characteristics of 2H and 18O in the basin of Dongting Lake and to further understand the interactions between precipitation, river water, lake water, and groundwater. Influenced by different monsoons, precipitation, river water, and lake water are enriched in isotopes in April but depleted in August. Stable isotopes of river water and lake water also have great spatial variations. Unlike river and lake water, groundwater has little seasonal isotopic variation, indicating that the transformation between surface water and groundwater is very slow.

20 wt% Pt0.55Co0.45/C catalysts were prepared using a chemical reduction method, with Vulcan XC-72 conducting furnace black and double-walled carbon nanotubes (DWCNTs) as the carbon supports, respectively. The catalysts were compared with commercial BASF 20 wt% Pt/C (using Vulcan XC-72 carbon as support). The materials were characterized by X-ray diffraction and transmission electron microscopy (TEM). The electrochemical performance of the Pt/C and Pt0.55Co0.45/C catalysts was evaluated by cyclic voltammetry and steady-state measurements. Electrochemical measurements indicated that the Pt0.55Co0.45 nanocatalysts exhibited improved activity in the oxygen reduction reaction (ORR) on DWCNTs compared to those on Vulcan XC-72 carbon. It is suggested that DWCNTs will provide better catalysis support than Vulcan XC-72 carbon.

Face image quality is an important factor affecting the accuracy of automatic face recognition. It is usually possible for practical recognition systems to capture multiple face images from each subject. Selecting face images with high quality for recognition is a promising stratagem for improving the system performance. We propose a learning to rank based framework for assessing the face image quality. The proposed method is simple and can adapt to different recognition methods. Experimental result demonstrates its effectiveness in improving the robustness of face detection and recognition.

Improvement of protein and starch quality is an important breeding objective for various wheat-based end products. The objectives of this study were to identify quantitative trait loci (QTLs) for flour protein content, wet gluten content, residue gluten content, gluten index, sedimentation volume, and rapid viscosity analysis parameters using two mapping populations. A total of 56 and 77 additive QTLs were detected in the NG population (derived from Gaocheng 8901 and Nuomai 1) and the SG population (derived from Shannong 01-35 and Gaocheng 9411), respectively. Of these QTLs, 20 additive QTLs from NG and 34 additive QTLs from SG accounted for more than 10 % of the phenotypic variance. All of the QTLs were distributed on 19 wheat chromosomes. At least 13 QTLs were detected in both environments in the two populations. Six pairwise common QTLs were found in the two populations. This study identified eight QTLs clusters (the number of QTLs ≥2) from NG and four QTLs clusters from SG. There was an important location flanking markers Glu-D1 and wPt3743 on chromosome 1D, which showed that they are pleiotropic or co-located QTLs. Most of the QTLs had higher phenotypic variation (>10 %). This study will facilitate the generation of improved wheat varieties with good quality via molecular-marker-assisted breeding.

Size of regions and discrimination of features are important to local approaches for facial landmark point location. After size of regions is determined, importance of features is obvious. Three features are considered in the paper, i.e. scale invariant feature transform (SIFT) features, local binary pattern (LBP) features, and Gabor wavelet features. Three logistic regressors are trained by using them respectively, and then they are used to testify the effect of these features on classification performance. On this basis, three fusion features are considered, i.e. SIFT features and Gabor wavelet features, SIFT features and LBP features, and Gabor wavelet features and LBP features. Three logistic regressors are trained by using them, respectively. They will be used to testify the effect of these fusion features on classification performance compared with single features. It can be noted from experiments that fusion features are more discriminative than single features, and that all of the features in the fusion features cooperate at classification stage, instead of single features.