Search

With the increase of coal mining in China, a large amount of waste coal gangue is produced. How to reuse waste coal gangue is an important research direction. The research results showed that the improvement of base asphalt mortar by coal gangue powder could improve the performance of matrix asphalt, however, search of rubber asphalt mortar modified by coal gangue powder is rarely reported. High and low-temperature performance is the critical performance of asphalt mortar. So the limestone powder modified base asphalt mortar (LPMBAM), limestone powder modified rubber asphalt mortar (LPMRAM), and coal gangue powder modified rubber asphalt mortar (CGPMRAM) are prepared, the high and low-temperature performance of asphalt mortar are analyzed by cone penetration tests and bending beam rheological tests (BBR). The results show that the cone penetration of asphalt mortar decreases with the increase of the filler-asphalt ratio and the decrease of the temperature. The shear strength and the stiffness modulus increase with the rise in the filler-asphalt ratio and the decrease in temperature. At the same filler-asphalt ratio and temperature, the order of cone penetration is CGPMRAM < LPMRAM < LPMBAM, and the order of shear strength is CGPMRAM > LPMRAM > LPMBAM, so the high-temperature performance of CGPMRAM is better than that of LPMRAM, much better than LPMBAM, the order of stiffness modulus is LPMRAM < CGPMRAM < LPMBAM so the low-temperature performance of LPMRAM and CGPMRAM is better than that of LPMBAM. By the double linear model, the optimum filler-asphalt ratio is determined to be 0.44~0.46 for LPMRAM and 0.42~0.43 for CGPMRAM. Microscopic tests show that the surface of coal gangue powder is rougher than that of limestone powder. The content of active oxides such as SiO2 and Al2O3 in coal gangue is about 7.8 times that of limestone powder. These physical and chemical properties make coal gangue powder able to adsorb rubber asphalt better and improve the high-temperature performance of CGPMRAM while slightly worsening the low-temperature performance of CGPMRAM but still better than LPMBAM. [ABSTRACT FROM AUTHOR]

Background. Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system that seriously threatens human life and health. This study aims to explore the role of the traditional Chinese medicine Leptochloa chinensis in the pathogenesis of RCC. Meanwhile, this study also revealed the molecular biological mechanism of its antitumor activity. Methods. Human RCC 786-O cells were cultured in the RPMI-1640 medium, which contains different concentrations of Leptochloa chinensis (1,000, 3,000, and 9,000 μg/ml). MTT and flow cytometry assays were used to detect the viability of 786-O cells. Transwell and wound healing assays were used to detect cell metastasis. The protein expression was observed by western blot analysis. Results. Leptochloa can inhibit cell proliferation and induce apoptosis in RCC 786-O cells. In addition, Leptochloa can weaken the migration and invasion of 786-O cells. More importantly, Leptochloa can block the mTOR pathway by inhibiting the protein expression of p-mTOR. Moreover, the high concentration of Leptochloa chinensis has a better inhibitory effect on 786-O cells. Conclusion. The traditional Chinese medicine Leptochloa chinensis inhibits the viability and metastasis of 786-O cells by blocking the mTOR pathway. [ABSTRACT FROM AUTHOR]

In comparison with marine environments, the occurrence of microplastics in freshwater environments is less understood. In the present study, we investigated microplastic pollution levels during 2015 in Taihu Lake, the third largest Chinese lake located in one of the most developed areas of China. The abundance of microplastics reached 0.01 × 10 6 –6.8 × 10 6 items/km 2 in plankton net samples, 3.4–25.8 items/L in surface water, 11.0–234.6 items/kg dw in sediments and 0.2–12.5 items/g ww in Asian clams ( Corbicula fluminea ). The average abundance of microplastics was the highest in plankton net samples from the southeast area of the lake and in the sediments from the northwest area of the lake. The northwest area of the lake was the most heavily contaminated area of the lake, as indicated by chlorophyll-α and total phosphorus. The microplastics were dominated by fiber, 100–1000 μm in size and cellophane in composition. To our best knowledge, the microplastic levels measured in plankton net samples collected from Taihu Lake were the highest found in freshwater lakes worldwide. The ratio of the microplastics in clams to each sediment sample ranged from 38 to 3810 and was negatively correlated to the microplastic level in sediments. In brief, our results strongly suggest that high levels of microplastics occurred not only in water but also in organisms in Taihu Lake. [ABSTRACT FROM AUTHOR]

ZY-3 is China’s first civilian high-resolution stereo surveying and mapping satellite, which is equipped with a three-line array panchromatic stereo camera. However, high-resolution satellite images (HRSIs) often suffer from satellite attitude oscillation, which can cause image distortions, and thus affect the geo-positioning accuracy. This paper presents an approach based on three-line array stereo images to detect and estimate the periodic distortions of ZY-3 that are caused by attitude oscillation. The proposed approach includes three main components, as follows: (1) A comprehensive image matching strategy, which combines the algorithms of the scale-invariant-feature-transform (SIFT), relative orientation, geometrically constrained cross-correlation (GC3), normalized cross-correlation (NCC) and least squares matching (LSM), is presented to generate dense conjugate points in multiple images. (2) A detection method is proposed to examine the relative image distortion, based on the back-projection residuals of the stereo pairs. By the use of the conjugate points, the corresponding elevation plane of each conjugate point is determined on the basis of the forward intersection. The conjugate points in an image are then forward-projected to the elevation plane to obtain their coordinates in the ground space, with the aid of the RPCs provided with the imagery. Furthermore, these ground points are back-projected to the other images. Therefore, the relative image distortions are detected by calculating the residuals between the back-projected points and the corresponding conjugate points in the image space. (3) The sum of the sinusoidal functions is presented to model the periodic distortions caused by the attitude oscillation. Based on the constructed distortion model, the absolute image distortions in the across-track direction are estimated by the use of the steepest descent algorithm. Three experiments were conducted to assess the proposed method for estimation of the periodic distortions of ZY-3 satellite images. The experimental results demonstrated the following: (1) an absolute periodic distortion of around 0.67 Hz in three-line array images of ZY-3 was, for the first time, estimated in the across-track direction. An amplitude of about 2.63 pixels was detected for the images acquired in the early period after satellite launch. However, the amplitude became smaller in the images acquired in the later periods. (2) With respect to the estimated image distortions from the intra-track images, the back-projected residuals between the inter-track images could be improved to a sub-pixel accuracy level after distortion compensation. (3) After conducting the periodic distortion compensation, the discrepancies of the check points (CKPs) could be reduced from 1.86, 1.42 and 0.73 pixels to 0.62, 0.41 and 0.51 pixels for the nadir, forward and backward images with five ground control points (GCPs), respectively. [ABSTRACT FROM AUTHOR]

Acid volatile sulfide (AVS), simultaneously extracted metals (SEMs), and total concentrations of trace elements (Cu, Cd, Pb, Zn, Ni, Hg, As, and Cr) were studied in sediment cores from Baihua Lake in southwest China. The molar ratios of SEMs to AVS for all samples were lower than 1.0 except for the 25- to 30-cm layer of the sample collected at location YPZ, indicating that the heavy metals were currently not significantly bioavailable as a whole to benthic organisms. Based on the sediment quality guidelines and the potential ecological risk assessment, Hg presented a high ecological risk for the water body. [ABSTRACT FROM AUTHOR]

The distribution characteristics of vanadium and its fraction based on the Tessier sequential extraction method were studied in surface sediment samples collected from Hongfeng Lake. The results of this study indicated that the total amount of vanadium in the sediment samples ranged from 124.0 to 213.0 mg/kg. The average percentages of exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter and residual were 2.79, 2.75, 30.40, 2.89 and 59.32, respectively. The concentrations of the different vanadium fractions decreased in the order of residual > bound to Fe-Mn oxides > bound to organic matter > exchangeable ≈ bound to carbonates. Furthermore, assessment using the enrichment factors (EF), the ratio of secondary to primary phase (RSP) and the secondary phases enrichment factor (SPEF) methods showed that the risk of vanadium in sediments especially from sites TLHJC and TX from Hongfeng Lake was generally high. [ABSTRACT FROM AUTHOR]

Abstract: Delayed response means that channels cannot achieve a new equilibrium state immediately following disruption; the channel requires a response time or relaxation time to reach equilibrium. It follows that the morphological state of fluvial system represents the cumulative effects of all previous disturbances and environmental conditions. A unique feature of the delayed response model for bankfull discharge is that the model is capable of representing the cumulative effects of all previous flow conditions when applied to predict the path/trajectories of bankfull discharge in response to altered flow regimes. In this paper, the delayed response model was modified by readjusting the weight for the initial boundary conditions and introducing a variable β with respect to time. The modified model was then applied to the bankfull discharge calculations for three selected river reaches of the Yellow River, with each reach having different geomorphic settings and constraints. Results indicated that the modified model can predict accurately the bankfull discharge variation in response to changes in flow discharge and sediment load conditions that have been dramatically altered in the past. Results also demonstrated the strong dependence of current bankfull discharge on the previous years'' flow conditions, with the relaxation time varied from 2 to 14 years, meaning that the bankfull discharge was not only affected by the flow discharge and sediment load in the current year, but also by those in previous 1 to 13 years. Furthermore, the relaxation time of bankfull discharge adjustment was inversely proportional to the long-term average suspended sediment concentrations, and this may be explained by fact that high sediment concentrations may have a high potential to perform geomorphic work and there is more sediment readily available to shape the channel boundary and geometry. [Copyright &y& Elsevier]

Abstract: This paper evaluates the applicability of the sediment transport methods developed by Engelund and Hansen, Ackers and White, Yang et al., and van Rijn, together with the Wuhan methods developed in China, to the Yellow River, which has highly concentrated and fine-grained sediment. The sediment data includes over 1000 observations from the Yellow River, 32 sets of data from a canal, and 266 sets of data from laboratory flumes. The best predictions were obtained by the Yang 1996 method, the Wuhan method, and the modified Wuhan method by Wu and Long, while reasonably good predictions were also provided by the van Rijn 2004 method. The Engelund and Hansen, the Ackers and White, and the van Rijn 1984 methods in their original forms are not applicable to the Yellow River. The predicted results for total load concentrations were as good as for bed-material concentrations, even though the total load includes a large portion of wash load. [Copyright &y& Elsevier]

The Codex Alimentarius Commission has established quantitative risk assessment standards and monitoring protocols for foodborne bacterial pathogens. Here, a simple protocol and a time and cost-effective platform were investigated based on the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify 4 pathogens, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Listeria monocytogenes , which were obtained from 7 types of vegetables. This protocol and platform will be helpful for routine monitoring of foodborne bacterial pathogens. Furthermore, the samples obtained from the Beijing region of China were monitored and reviewed, and the survey results showed 26.0% of samples tested positive for microorganisms. E. coli was present most often (14.0%) and showed similar positive proportions among all of the vegetable products. In addition, exogenous contamination from the transport, storage or primary processing of vegetables requires special attention. • Investigate a universal platform based on the MALDI-TOF MS technique for identifying 4 microbial pathogens. • Offers a promising tool for bacterial identification in basic microbiology laboratories. • Summarized the current status and reviewed the pathogen samples obtained from the Beijing region of China. [ABSTRACT FROM AUTHOR]

The conventional typical meteorological year (TMY) based on continuous-year original meteorological records without considering abrupt climate changes (ACC) may not be able to represent a real "typical" climate properly. Consequently, building performance analyses and simulations based on TMY may be not accurate. Current research rarely tackles this issue in TMY development. This paper presents an innovative TMY development with the consideration of ACC in the original meteorological records. It is based on the Chinese standard weather database method (CSWD) with the meteorological records of six Chinese cities in different climate zones. It applies the Moving t-test method to identify and exclude ACC points and to refine the timescales for TMY development. It also depicts the development of individual typical meteorological months again with the ACC impact to improve the accuracy of TMY. The method has been verified in several building energy consumption and thermal comfort analyses. The results demonstrate that the analysis based on the new TMY climate datasets when considering ACC will end up with less energy consumption and better thermal performance compared to the analyses based on the conversion dataset without considering ACC. This experimental research will refine TMY development, and further improve building energy performance analysis and design. [ABSTRACT FROM AUTHOR]

• Evaluate the applicability of composite steel slag as subgrade filler. • Clarify the influence of different mixing proportions on subgrade performance. • Recommend the conversion relationship between CBR and resilience modulus. • Predict the displacements of composite steel slag as subgrade filler. The utilization rate of steel slag (SS) in China is much lower than that in developed countries. In this study, water-cooled SS and hot-spray poured SS were analyzed as raw materials. Six kinds of composite SS mixtures with different mixing proportions were then designed, and their properties such as expansion rate, California bearing ratio (CBR) and modulus of resilience were examined. Based on the different mixing proportions of SS, and regression analysis, the conversion relationship between CBR value and subgrade resilience modulus were recommended. Finally, the composite SS subgrade settlement was analyzed by ABAQUS, and the economic benefits were analyzed. [ABSTRACT FROM AUTHOR]

Background: Traumatic fractures occur frequently worldwide. However, research remains limited on the association between short-term exposure to temperature and traumatic fractures. This study aims to explore the impact of apparent temperature (AT) on emergency visits (EVs) due to traumatic fractures., Methods: Based on EVs data for traumatic fractures and the contemporary meteorological data, a generalized Poisson regression model along with a distributed lag nonlinear model (DLNM) were undertaken to determine the impact of AT on traumatic fracture EVs. Subgroup analysis by gender and age and sensitivity analysis were also performed., Results: A total of 25,094 EVs for traumatic fractures were included in the study. We observed a wide "J"-shaped relationship between AT and risk of traumatic fractures, with AT above 9.5 °C positively associated with EVs due to traumatic fractures. The heat effects became significant at cumulative lag 0-11 days, and the relative risk (RR) for moderate heat (95th percentile, 35.7 °C) and extreme heat (99.5th percentile, 38.8 °C) effect was 1.311 (95% CI: 1.132-1.518) and 1.418 (95% CI: 1.191-1.688) at cumulative lag 0-14 days, respectively. The cold effects were consistently non-significant on single or cumulative lag days across 0-14 days. The heat effects were higher among male and those aged 18-65 years old. The sensitivity analysis results remained robust., Conclusion: Higher AT is associated with cumulative and delayed higher traumatic fracture EVs. The male and those aged 18-65 years are more susceptible to higher AT., (© 2024. The Author(s).)

Based on the mussel-inspired adhesive interface (Fe 3 O 4 -g-C 3 N 4 @PDA), a novel bionic metal-organic framework (Fe 3 O 4 -g-C 3 N 4 -PDA@MIL-101) was successfully prepared. The composite featured a high specific surface area and a multi-microchannel structure, as well as strong thermochemical stability. The structural property of Fe 3 O 4 -g-C 3 N 4 -PDA@MIL-101(Fe) was characterized, and the results indicated that Fe 3 O 4 , PDA, and MIL-101(Fe) were uniformly coated on the g-C 3 N 4 surface. The adsorption and desorption of organophosphorus pesticides with Fe 3 O 4 -g-C 3 N 4 -PDA@MIL-101(Fe) were evaluated by batch experiments. This composite showed high adsorption efficiency and selective removal of coralox, phosalone, and chlorpyrifos. Under the optimal conditions, three organophosphorus pesticides were adsorbed from Chinese cabbage and green onion samples with Fe 3 O 4 -g-C 3 N 4 -PDA@MIL-101(Fe). The analytical method exhibited high sensitivity (LOD, 0.19-2.34 μg/L; LOQ, 0.65-7.82 μg/L), excellent practicality, and good stability, suggesting that Fe 3 O 4 -g-C 3 N 4 -PDA@MIL-101 was an ideal candidate magnetic adsorbent for the removal of organophosphorus pesticides in Chinese cabbage and green onion samples., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Carbofuran residue in vegetables is a concern to human health. Direct competitive enzyme-linked immunosorbent assay (dcELISA) and dipstick immunoassay were developed in the present study. The dcELISA showed a 50% inhibition concentration (IC 50 ) and working range of 1.3 and 0.2 to 7.5 ng/mL, respectively, while the cutoff value of dipstick immunoassay was 20 ng/mL. Applying the two immunoassays, we achieved the goal of rapid screening of carbofuran residue in commercial vegetables with a simple sample processing method. Among 46 leek, 39 potato, and 39 sweet potato samples, carbofuran residue was detected in 22% of the leek samples, and two samples exceeded the maximum residue limit of China (0.02 mg/kg). In addition, carbofuran residue was found at less than 2.5 ng/g in one potato and one sweet potato samples. The residual level of carbofuran measured by immunoassays agreed well with those determined by ultra-performance liquid chromatography tandem mass spectrometry. To ensure food safety and human health, it is greatly necessary and meaningful to monitor carbofuran residue in commercial vegetables. PRACTICAL APPLICATION: Rapid monitoring of carbofuran residue in vegetables is very necessary and important for consumers, regulatory agencies, and food industry., (© 2019 Institute of Food Technologists®.)

The present study investigated the concentrations of residues of four groups of pesticides in the People's Republic of China: organophosphorus, carbamate, pyrethroid, and triazine pesticides. Twenty-six pesticides were examined using gas chromatography-tandem mass spectrometry and liquid chromatography-tandem mass spectrometry in 2,169 samples of 12 typical vegetables collected from 15 provinces in China. The results showed that 908 (41.9%) samples were positive, with 133 (6.1%) samples exceeding the limit legal in China. Leafy vegetables showed higher positive rates than fruits and root vegetables. Organophosphorus, carbamate, pyrethroid, and triazine pesticides were found in 11.8, 7.7, 13.9, and 10.9% of the samples, respectively, which provided important information on current concentrations of cumulative assessment group pesticide residues for vegetables in China. Of the positive samples, a slight violation rate of 1.9% for the organophosphorus pesticide category exceeded China's maximum residue limits. Positive rates for chlorpyrifos in celery, pak-choi, and leeks were higher, but fewer exceeded China's maximum residue limits.