854 results on '"Ye, Chen"'
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2. Finite-Element-Based Time-Dependent Service Life Prediction for Carbonated Reinforced Concrete Aqueducts
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Lan Zhang, Ri-Sheng He, Long-Wen Zhang, and Yan-Ye Chen
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finite element method ,aqueduct ,dual power transformation ,HUT ,time-dependent reliability ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study proposes a time-dependent reliability analysis method for aqueduct structures based on concrete carbonation and finite element analysis. The primary goal of this study is to improve the reliability assessment of reinforced concrete aqueducts by incorporating environmental factors such as carbonation over time. First, a three-dimensional finite element model of a reinforced concrete aqueduct is established using the Midas 2022 Civil software, incorporating a time-varying function derived from a predictive model of concrete carbonation depth. Point estimation is then integrated with structural finite element analysis to calculate the first four moments of random variables as functions of concrete carbonation. Additionally, the original performance function is transformed into a normal distribution using dual power transformation and the Jarque–Bera test. The high-order unscented transformation (HUT) is subsequently employed to estimate the first four moments of the transformed performance function, facilitating the calculation of time-varying reliability indices for the carbonated concrete aqueduct. Based on the time-varying reliability index data, a reliability function corresponding to different time points is fitted and applied to service life prediction. The results demonstrate that the proposed method effectively reduces large errors associated with the fourth-moment method in calculating large reliability indices. Furthermore, the comparison with Monte Carlo simulation (MCS) results validates the high efficiency and accuracy of the proposed method, offering a valuable tool for addressing the reliability challenges of aqueducts exposed to carbonation and other environmental factors over time.
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- 2025
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3. Research on Nanoparticle-Enhanced Cooling Technology for Oil-Based Drilling Fluids
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Xudong Wang, Pengcheng Wu, Ye Chen, Ergang Zhang, Xiaoke Ye, Qi Huang, Ruolan Wang, Gui Wang, and Gang Xie
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oil-based drilling fluids ,nanoparticles ,specific heat capacity ,the rheology of drilling fluids ,wellbore cooling ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Drilling fluids are critical in oil and gas well drilling, particularly deep shale gas drilling. In recent years, applying nanoparticles as additives in drilling fluids has received widespread attention to address the various challenges associated with deep shale gas drilling. This study focused on the performance of three nanoparticle-enhanced oil-based drilling fluids (OBDFs), carbon nanotubes (CNTs), silicon dioxide (SiO2), and aluminums oxide (Al2O3) in terms of improving thermal capacity and cooling efficiency. The potential of the nanoparticles to improve the thermal management capability of the drilling fluids was evaluated by measuring specific heat capacity and thermal conductivity. The results showed that CNTs exhibited the most significant improvement, with thermal conductivity increasing by 7.97% and specific heat capacity by 19.38%. The rheological properties and high temperature and high pressure (HTHP) filtration performance of the nanoparticle-enhanced OBDFs were evaluated, demonstrating that CNTs and SiO2 significantly improved the rheological stability of the drilling fluids and reduced the filtration loss under high temperature conditions. When 3% CNTs were added, the HTHP filtration loss was reduced by 42.86%, exhibiting excellent sealing properties. The cooling effect of different nanoparticles was evaluated by calculating their effects on the bottomhole temperature. The results showed that CNTs performed the best in lowering the bottomhole temperature by 4.53 °C, followed by SiO2 by 1.47 °C and Al2O3 by only 0.88 °C. The results showed that CNTs were the most effective in lowering the bottomhole temperature. These results indicated that nanoparticles as additives to drilling fluids could significantly increase the thermal capacity and cooling efficiency of OBDFs, making them effective additives for high-temperature deep shale gas drilling applications.
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- 2024
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4. Study on Evaluation and Prediction for Shale Gas PDC Bit in Luzhou Block Sichuan Based on BP Neural Network and Bit Structure
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Ye Chen, Yu Sang, Xudong Wang, Xiaoke Ye, Huaizhong Shi, Pengcheng Wu, Xinlong Li, and Chao Xiong
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bit structure ,Spearman rank correlation coefficient ,BP neural network ,ROP prediction ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Deep and ultra-deep shale gas resources have great potential, but well drilling faces many challenges. The Polycrystalline Diamond Compact (PDC) bit has become the primary rock-breaking instrument for oil and gas drilling. Reasonable bit structure designs can promote rock-breaking efficiency and extend service life. In this study, reverse modeling technology is used to analyze the structural characteristics of PDC bits collected in the field, and the influence of the structural characteristics of the bit at a specific interval on the rate of penetration (ROP) and drill footage is investigated using the Spearman rank correlation coefficient method. The number of blades, cutting angle of the cutters, crown rotation radius, internal cone angle, and diameter of the cutters are discovered to be the main structural characteristics that affect the ROP and footage of the bits, and the degree of influence varies depending on the formation conditions. The number of blades, crown rotation radius, inner cone angle, and cutting angle of the cutters have a significant impact on the ROP, whereas blade thickness, gauge length, gauge width, nozzle equivalent diameter have a significant impact on the bit footage. In addition, a back propagation (BP) neural network is utilized to build a prediction model of bit footage and ROP over a certain interval based on the structural characteristics of the bit. The goodness of fit of the model is greater than 85%, and its accuracy is high. Based on the usage of the bit, the evaluation and prediction of the bit can provide a reference for the structural design and optimization of the bit in a specific interval, guide the bit selection work, rationally plan the drilling operation, and reduce the drilling cost.
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- 2024
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5. Network Pharmacology-Based Analysis on the Action Mechanism of Oleanolic Acid to Alleviate Osteoporosis
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Yi Wu, Li-Jie Gao, Ying-Sai Fan, Ye Chen, and Qin Li
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Chemistry ,QD1-999 - Published
- 2021
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6. Study on Asymmetric Support of Anchor Cable with C-Shaped Tube in Inclined Coal Seam Roadway
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Renliang Shan, Tianwen Li, Weijun Liu, Ye Chen, Shuguo Shi, and Gengzhao Li
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anchor cable with C-shaped tube ,double shear test ,inclined coal seam ,asymmetric deformation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In view of the complex asymmetric deformation characteristics of inclined coal seam roadways and the tensed shear failure of anchor cable supports, the asymmetric support scheme of an anchor cable with a C-shaped tube is proposed. In order to study its supporting effect on an inclined coal seam roadway, this paper first explores the difference in shear performance between an anchor cable with a C-shaped tube and an anchor cable through double shear tests. Then, based on the asymmetric deformation characteristics of an inclined coal seam roadway in the Pangpangta Mine, a numerical simulation is used to study the asymmetric support effect of an anchor cable with a C-shaped tube in an inclined coal seam roadway. The results of the double shear test show that the anchor cable with the C-shaped tube has stronger resistance to shear load than that of the anchor cable. Through the results of the numerical simulation, the original stress field distribution on both sides of the roadway was found to be uneven due to the influence of the coal seam dip angle, and after the excavation of the inclined coal seam roadway, the displacement and plastic zone distribution on both sides showed obvious asymmetric characteristics. Compared with the symmetric support, the asymmetric support can obviously alleviate the asymmetric deformation characteristics of the two sides and effectively control the deformation and plastic failure zone of the roadway. The anchor cable with the C-shaped tube has better resistance to shear deformation than that of the anchor cable. The anchor cable with the C-shaped tube can reduce the deformation and plastic area of the roadway more effectively.
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- 2023
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7. Phase engineering of metal‐organic frameworks
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Chen Ma, Long Zheng, Gang Wang, Jun Guo, Liuxiao Li, Qiyuan He, Ye Chen, and Hua Zhang
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crystal phase ,metal‐organic frameworks ,phase engineering ,phase transformation ,phase‐controlled synthesis ,Chemistry ,QD1-999 ,Biology (General) ,QH301-705.5 - Abstract
Abstract As an important category of porous crystalline materials, metal‐organic frameworks (MOFs) have attracted extensive research interests owing to their unique structural features such as tunable pore structure and enormous surface area. Besides controlling the size, dimensionality, and composition of MOFs, further exploring the crystal‐phase‐dependent physicochemical properties is essential to improve their performances in various applications. Recently, great progress has been achieved in the phase engineering of nanomaterials (PEN), which provides an effective strategy to tune the functional properties of nanomaterials by modulating the arrangement of atoms. In this review, we adopt “phase” instead of “topology” to describe the crystal structure of MOFs and summarize the recent advances in phase engineering of MOFs. The two main strategies used to control the phase of MOFs, that is, phase‐controlled synthesis and phase transformation of MOFs, will be highlighted. The roles of various reaction parameters in controlling the crystal phase of MOFs are discussed. Then, the phase dependence of MOFs in various applications including luminescence, adsorption, and catalysis are introduced. Finally, some personal perspectives about the challenges and opportunities in this emerging field are presented.
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- 2022
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8. Computing Investigations of Molecular and Atomic Vibrations of Ice IX
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Zeng-Ji Zhao, Xiao-Ling Qin, Jing-Wen Cao, Xu-Liang Zhu, Ye-Chen Yang, Hao-Cheng Wang, and Peng Zhang
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Chemistry ,QD1-999 - Published
- 2019
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9. Supramolecular Self-Assembly Strategy towards Fabricating Mesoporous Nitrogen-Rich Carbon for Efficient Electro-Fenton Degradation of Persistent Organic Pollutants
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Ye Chen, Miao Tian, and Xupo Liu
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supramolecule ,mesoporous nitrogen-rich carbon ,carbon fixation ,electro-Fenton ,organic pollutant degradation ,Chemistry ,QD1-999 - Abstract
The electro-Fenton (EF) process is regarded as an efficient and promising sewage disposal technique for sustainable water environment protection. However, current developments in EF are largely restricted by cathode electrocatalysts. Herein, a supramolecular self-assembly strategy is adopted for synthetization, based on melamine–cyanuric acid (MCA) supramolecular aggregates integrated with carbon fixation using 5-aminosalicylic acid and zinc acetylacetonate hydrate. The prepared carbon materials characterize an ordered lamellar microstructure, high specific surface area (595 m2 g−1), broad mesoporous distribution (4~33 nm) and high N doping (19.62%). Such features result from the intrinsic superiority of hydrogen-bonded MCA supramolecular aggregates via the specific molecular assembly process. Accordingly, noteworthy activity and selectivity of H2O2 production (~190.0 mg L−1 with 2 h) are achieved. Excellent mineralization is declared for optimized carbon material in several organic pollutants, namely, basic fuchsin, chloramphenicol, phenol and several mixed triphenylmethane-type dyestuffs, with total organic carbon removal of 87.5%, 74.8%, 55.7% and 54.2% within 8 h, respectively. This work offers a valuable insight into facilitating the application of supramolecular-derived carbon materials for extensive EF degradation.
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- 2022
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10. Research Progress on the Preparation and Applications of Laser-Induced Graphene Technology
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Yani Guo, Cheng Zhang, Ye Chen, and Zhengwei Nie
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laser-induced graphene ,preparation process ,signal sensing ,environmental protection ,energy storage ,Chemistry ,QD1-999 - Abstract
Graphene has been regarded as a potential application material in the field of new energy conversion and storage because of its unique two-dimensional structure and excellent physical and chemical properties. However, traditional graphene preparation methods are complicated in-process and difficult to form patterned structures. In recent years, laser-induced graphene (LIG) technology has received a large amount of attention from scholars and has a wide range of applications in supercapacitors, batteries, sensors, air filters, water treatment, etc. In this paper, we summarized a variety of preparation methods for graphene. The effects of laser processing parameters, laser type, precursor materials, and process atmosphere on the properties of the prepared LIG were reviewed. Then, two strategies for large-scale production of LIG were briefly described. We also discussed the wide applications of LIG in the fields of signal sensing, environmental protection, and energy storage. Finally, we briefly outlined the future trends of this research direction.
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- 2022
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11. Centrifugal Spinning Enables the Formation of Silver Microfibers with Nanostructures
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Xujing Zhang, Songsong Tang, Zhaokun Wu, Ye Chen, Zhen Li, Zongqian Wang, and Jian Zhou
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centrifugal spinning ,silver nanowires ,nanofibers ,annealing ,Chemistry ,QD1-999 - Abstract
Silver nanowires (AgNWs) have received much attention and application in transparent electrodes, wearable electronic devices, and sensors. The hope is for these nanowires to eventually replace the most commonly used transparent electrode material—indium tin oxide (ITO). However, electrospinning used for the preparation of AgNWs on a large scale is limited by its low productivity and high electric field, while the alcohol-thermal method is limited to mixing by-product silver nanoparticles in silver nanowires. We demonstrate a novel and simple centrifugal spinning approach in order to successfully fabricate ultra-long silver microfibers based on AgNO3 and polyvinyl pyrrolidone (PVP). The centrifugal-spun precursor fiber and silver fiber can be prepared to as thin as 390 and 310 nm, respectively. Annealed fibers show typical nanostructures with grains down to a minimum size of 51 nm. Combinations of different parameters, including concentrations of PVP, needle size, and annealing temperature are also investigated, in order to optimize the spinning process of ultra-long silver microfibers. The feasibility of preparing silver microfibers by centrifugal spinning is preliminarily verified, examining prospects for mass production. Furthermore, numerous strategies related to assisting the creation of silver nanofibers using centrifugal spinning are presented as possibilities in future development.
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- 2022
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12. Perspectives towards Sub-Ångström Working Regime of the European X-ray Free-Electron Laser with Low-Emittance Electron Beams
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Ye Chen, Frank Brinker, Winfried Decking, Matthias Scholz, and Lutz Winkelmann
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sub-ångström ,free-electron lasers ,SASE ,low-emittance ,start-to-end simulations ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Sub-ångström working regime refers to a working state of free-electron lasers which allows the generation of hard X-rays at a photon wavelength of 1 ångström and below, that is, a photon energy of 12.5 keV and above. It is demonstrated that the accelerators of the European X-ray Free-Electron Laser can provide highly energetic electron beams of up to 17.5 GeV. Along with long variable-gap undulators, the facility offers superior conditions for exploring self-amplified spontaneous emission (SASE) in the sub-ångström regime. However, the overall FEL performance relies quantitatively on achievable electron beam qualities through a kilometers-long accelerator beamline. Low-emittance electron beam production and the associated start-to-end beam physics thus becomes a prerequisite to dig in the potentials of SASE performance towards higher photon energies. In this article, we present the obtained results on electron beam qualities produced with different accelerating gradients of 40 MV/m–56 MV/m at the cathode, as well as the final beam qualities in front of the undulators via start-to-end simulations considering realistic conditions. SASE studies in the sub-ångström regime, using optimized electron beams, are carried out at varied energy levels according to the present state of the facility, that is, a pulsed mode operating with a 10 Hz-repetition 0.65 ms-long bunch train energized to 14 GeV and 17.5 GeV. Millijoule-level SASE intensity is obtained at a photon energy of 25 keV at 14 GeV electron beam energy using a gain length of about 7 m. At 17.5 GeV, half-millijoule lasing is achieved at 40 keV. Lasing at up to 50 keV is demonstrated with pulse energies in the range of a few hundreds and tens of microjoules with existing undulators and currently achievable electron beam qualities.
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- 2021
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13. Modulation of Ferroelectric and Optical Properties of La/Co-Doped KNbO3 Ceramics
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Xue Zhang, Ruijuan Qi, Shangwei Dong, Shuai Yang, Chengbin Jing, Lin Sun, Ye Chen, Xuekun Hong, Pingxiong Yang, Fangyu Yue, and Junhao Chu
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lead-free ferroelectrics ,ceramics ,microstructure ,optical properties ,Chemistry ,QD1-999 - Abstract
The phase transition, microscopic morphology and optical and ferroelectric properties are studied in a series of La- and Co-doped KNbO3-based ceramics. The results show that the doping induces the transformation from the orthorhombic to the cubic phase of KNbO3, significantly reduces the optical bandgap and simultaneously evidently improves the leakage, with a slight weakening of ferroelectric polarization. Further analysis reveals that (i) the Co doping is responsible for the obvious reduction of the bandgap, whereas it is reversed for the La doping; (ii) the slight deterioration of ferroelectricity is due to the doping-induced remarkable extrinsic defect levels and intrinsic oxygen vacancies; and (iii) the La doping can optimize the defect levels and inhibit the leakage. This investigation should both provide novel insight for exploring the bandgap engineering and ferroelectric properties of KNbO3, and suggest its potential applications, e.g., photovoltaic and multifunctional materials.
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- 2021
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14. Transcriptomics‐based identification and characterization of genes related to sugar metabolism in ‘Hongshuijing’ pitaya
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Yemiao Xing, Yonghua Qin, Rong Zhang, Canbin Chen, Jietang Zhao, Zhike Zhang, Qingzhu Hua, Jian-ye Chen, Muthusamy Ramakrishnan, Fangfang Xie, and Guibing Hu
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Ecology ,Renewable Energy, Sustainability and the Environment ,food and beverages ,Fruit Flavor ,Fructose ,Plant Science ,Biology ,Carbohydrate metabolism ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,chemistry.chemical_compound ,Invertase ,chemistry ,biology.protein ,Sucrose synthase ,Food science ,KEGG ,Sugar ,Gene ,Ecology, Evolution, Behavior and Systematics - Abstract
Sugar composition not only affects fruit flavor but is also an important determinant of fruit taste and consumer preference. In this study, changes in the sugar content and sugar-metabolizing enzymes were investigated from different sections of various fruit development phases of ‘Hongshuijing’ pitaya (Hylocereus monacanthus). Genes related to sugar metabolism were also screened by transcriptome analyses. The results indicated that glucose was the major sugar in mature pitaya fruit, and was mainly regulated by vacuolar acid invertase (VAI) and sucrose synthase (SS) (degradative direction). Sugar accumulation varied in pulp between different sections of the pitaya fruit. VAI, neutral invertase (NI) and SS (degradative direction) are crucial enzymes for sugar accumulation in pitaya. The expression of 17 genes related to sucrose metabolism and obtained from seven databases [NCBI non-redundant protein database (Nr), NCBI non-redundant nucleotide sequence database (Nt), EuKaryotic Orthologous Groups (KOG), The Protein Families (Pfam), Kyoto Encyclopedia of Genes and Genomes (KEGG), Swiss-prot, and Gene Ontology (GO)] were analyzed in different pitaya pulp sections. HpVAI1 had the highest relative expression level on the 29th day after pollination (DAP). Positive correlations were found between HpVAI1 expression and VAI activity; HpNI4 and NI activity; HpSS2, HpSS5, and SS activity (synthetic direction), indicating that HpVAI1, HpNI4, and HpSS2 and HpSS5 were involved in the regulation of VAI, NI, and SS (synthetic direction), respectively. HpVAI1 and HpNI4 regulated sucrose degradation and the accumulation of glucose and fructose, while HpSS2 and HpSS5 regulated sucrose synthesis. These results suggest that HpVAI1 plays a key role in sugar metabolism during fruit development of ‘Hongshuijing’ pitaya. The results of this study provide new information about sugar metabolism in pitaya fruit that could help improve fruit quality and the breeding of new cultivars.
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- 2022
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15. Self-sacrificial template synthesis of Fe, N co-doped porous carbon as efficient oxygen reduction electrocatalysts towards Zn-air battery application
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Tianfang Yang, Yang Liu, Ye Chen, Xupo Liu, and Shuyan Gao
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Battery (electricity) ,Materials science ,Doping ,Graphitic carbon nitride ,General Chemistry ,Electrocatalyst ,Cathode ,Catalysis ,law.invention ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Methanol ,Cyclic voltammetry - Abstract
Designing highly efficient non-precious based electrocatalysts for oxygen reduction reaction (ORR) is of significance for the rapid development of metal-air batteries. Herein, a hydrothermal-pyrolysis method is employed to fabricate Fe, N co-doped porous carbon materials as effective ORR electrocatalyst through adopting graphitic carbon nitride (g-C3N4) as both the self-sacrificial templates and N sources. The g-C3N4 provides a high concentration of unsaturated pyridine-type N to coordinate with iron to form Fe-N active sites. Through adjusting the Fe doping amounts, it is proved that appropriate Fe doping content is conducive to the construction of abundant defects and active sites of Fe-N. The as-prepared catalyst exhibits superior electrocatalytic ORR performance in alkaline media with half-wave potential (E1/2 = 0.82 V) and onset potential (Eonset = 0.95 V), equivalent to the commercial Pt/C catalyst. Moreover, there is almost no activity loss after 10 k continuous cyclic voltammetry cycles and methanol tolerance, indicating the excellent durability and superior methanol tolerance. Remarkably, when assembled as the cathode in a Zn-air battery, the device displays a power density of 99 mW/cm2, an open-circuit potential of 1.48 V and long-term discharge-charge cycling stability, indicating the promising potential to substitute the Pt catalyst for practical application.
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- 2022
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16. Investigation on Modeling and Formation Mechanism of Dynamic Rotational Error for Spindle-Rolling Bearing System
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Gaofeng Hu, Ye Chen, Liangyu Cui, Gang Jin, Tingjian Wang, Houjun Qi, and Yanling Tian
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spindle-rolling bearing system ,dynamic rotational error ,nonlinear bearing model ,surface waviness ,dynamic unbalance ,disturbance force ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In the field of precision machining, the spindle-rolling bearing (SRB) system is widely used on the machine tool as one of the most fundamental and important components. The rotational error motions of the SRB system have significant effects on the machining accuracy (contour accuracy and surface roughness). Over the past decades, much work has been focused on the measurement of spindle balancing and rotational error motions, the vibrations response induced by the nonlinear stiffness and surface waviness of the bearing. However, the formative mechanism of the rotational error motions for the SRB system is not well understood. In this paper, the dynamic model of the SRB system considering the bearing nonlinearity is established. Seeking to reveal the effects of surface waviness of the bearing raceway, unbalance mass and disturbance force on the dynamic rotational error, the modeling method and formative mechanism of the dynamic rotational error for the SRB system is explored both theoretically and experimentally. Then, numerical simulation is performed to analyze the influence of the bearing raceway waviness, unbalance mass and disturbance force on the dynamic rotational error. An experimental setup is established based on a typical SRB system and a series of experiments are carried out. The experimental results are in good agreement with the theoretical and simulation results, which can demonstrate the feasibility and validity of the modeling method. Furthermore, this method can be effectively applied to the design and development phases of an SRB system to improve dynamic rotational accuracy.
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- 2020
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17. Analysis on Dynamic Contact Characteristics and Dynamic Stiffness Estimating Method of Single Nut Ball Screw Pair Based on the Whole Rolling Elements Model
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Ye Chen, Chunyu Zhao, Zhenjun Li, and Zechen Lu
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ball screw pair ,dynamic load distribution ,dynamic contact characteristics ,dynamic stiffness ,sensorless estimated stiffness ,CNC machine tools ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The purpose of this paper is investigating the characteristics of dynamic contact and dynamic stiffness of the single nut ball screw pair (SNBSP). Then a new sensorless method is proposed to extract the SNBSP dynamic contact stiffness of a mass production CNC machine tool feed system. First of all, the transformation relationship between each coordinate system of SNBSP is established. Secondly, the dynamic model of all ball–raceway contact pairs is established. Based on this, a dynamic contact stiffness model is established. The dynamic contact parameters are obtained by the numerical method. It is found that the influence of screw speed on screw and nut raceway normal force distribution are opposite. This will affect the variations of dynamic contact stiffness. It is also clear that the effect of axial load on dynamic stiffness is significant. Then, an effective method is proposed to estimate the dynamic contact stiffness of a mass production CNC machine tool feed system without any external sensors. The axial force of feed system is estimated by using torque current of servo motor. Current signals can be obtained through FANUC Open CNC API Specifications (FOCAS) library functions, and then dynamic contact stiffness can be calculated through the stiffness model without external sensors. Finally, a feed system dynamic model is built, and the contact model and sensorless stiffness estimating method are verified by experiments in this dynamic system.
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- 2020
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18. Investigation on Sensorless Estimating Method and Characteristics of Friction for Ball Screw System
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Ye Chen, Siyu Zhang, Yanzhou Zhang, Zechen Lu, and Chunyu Zhao
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friction ,ball screw system ,sensorless estimated friction ,CNC machine tool ,position-dependent characteristics ,velocity-dependent characteristics ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this study, a novel sensorless method is developed to estimate the friction in a ball screw system using asynchronous experimental data for a worktable position (WP) and the servo motor torque current (SMTC), which is collected by the FOCAS library functions from a FANUC digital control system. The corresponding time stamps are retrieved by a high-resolution performance counter in Windows. The fluctuations in friction over the whole travel distance of the worktable (WTDOW) are analyzed using a piecewise polynomial fitting algorithm to extract the instantaneous average friction value (IAFV) and the friction fluctuating signal (FFS). The IAFVs can describe the effect of the WP and the pitch errors of the shaft on the friction. The FFT results of the FFS show that the friction depends on the rolling tool, the pitch of the shaft and the refeeding of the balls in the ball screw and linear ball rail guides. The experimental results show that the estimated friction can capture the characteristic spectra of the FFS. The effects of the feed velocity and direction, the effects of the WP on the IAFV, and the frequencies and amplitudes of the significant FFT components are discussed. The nonuniform pitch errors of the shaft impact the repeatability of the IAFVs at a given WP. The variations in the mean value of the IAFVs with the feed velocity for tests at a fixed WP show nonconventional Stribeck behavior. These results also demonstrate that the friction force varies with the WP, which is not captured by Stribeck characteristics. This study provides an effective method to evaluate the performance of a ball screw system and to predict the friction in that system without the use of sensors.
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- 2020
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19. Quantitative analysis of late iodine enhancement using dual-layer spectral detector computed tomography: comparison with magnetic resonance imaging
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Zhengyu Jin, Xiaomei Lu, Cheng Xu, Lu Lin, Peijun Liu, Mani Vembar, Xue Lin, Ye-Chen Han, Yining Wang, and Yang Hou
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Materials science ,medicine.diagnostic_test ,Detector ,Dual layer ,chemistry.chemical_element ,Computed tomography ,Magnetic resonance imaging ,Iodine ,Nuclear magnetic resonance ,chemistry ,medicine ,Original Article ,Radiology, Nuclear Medicine and imaging ,Quantitative analysis (chemistry) - Abstract
BACKGROUND: To evaluate the segmental myocardial extracellular volume (ECV) fraction and to define a threshold ECV value that can be used to distinguish positive late gadolinium enhancement (LGE) segments from negative myocardial segments using dual-layer spectral detector computed tomography (SDCT), with magnetic resonance imaging (MRI) as a reference. METHODS: Fifty-six subjects with cardiac disease or suspected cardiac disease, underwent both late iodine enhancement on CT (CT-LIE) scanning and late gadolinium enhancement on MRI (MRI-LGE) scanning. Each procedure occurred within a week of the other. Global and segmental ECVs of the left ventricle were measured by CT and MRI images. According to the location and pattern of delayed enhancement on MRI image, myocardial segments were classified into 3 groups: ischemic LGE segments (group 1), nonischemic LGE segments (group 2) and negative LGE segments (group 3). The correlation and agreement between CT-ECV and MRI-ECV were compared on a per-segment basis. Receiver operating characteristic (ROC) curve analysis was performed to establish a threshold for LIE detection. RESULTS: Among the 56 patients, 896 segments were analyzed, and of these, 73 segments were in group 1, 229 segments were in group 2, and 594 segments were in group 3. In segmental analysis, CT-ECV in group 3 (27.0%; 24.9–28.9%) was significantly lower than that in group 1 (33.2%; 30.7–36.3%) and group 2 (34.9%; 32.3–39.8%; all P
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- 2022
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20. Choline-induced SLC5A7 impairs colorectal cancer growth by stabilizing p53 protein
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Jiamei Fu, J. Li, Chen Na, Zhiyuan Jiang, Xiaonan Yin, Ye Chen, Yanhong Ji, Xiaolan Su, Hongxin Deng, Lei Dai, Meng Qiu, Wei Huang, Bo Zhang, Chao Fang, Yuan Yin, and Yang Li
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Cancer Research ,Colorectal cancer ,Choline ,chemistry.chemical_compound ,Cell Line, Tumor ,medicine ,Humans ,Protein Interaction Maps ,Cell Proliferation ,Symporters ,biology ,Wild type ,Proto-Oncogene Proteins c-mdm2 ,medicine.disease ,digestive system diseases ,Solute carrier family ,Gene Expression Regulation, Neoplastic ,Oncology ,chemistry ,P53 protein ,biology.protein ,Cancer research ,Mdm2 ,Ectopic expression ,Tumor Suppressor Protein p53 ,Colorectal Neoplasms ,Function (biology) - Abstract
The members of the solute carrier (SLC) superfamily are vital membrane transporters in human cells. In the present study, we determine the expression and function of SLC5 family members in colorectal cancer (CRC). Expression analysis based on The Cancer Genome Atlas database and potential clinical relation analysis based on the Oncomine database indicate that SLC5A7 is downregulated and is predicted to correlate with the staging, and prognosis response of CRC. Additional results demonstrate that SLC5A7 is downregulated and correlates with good prognosis in patients with CRC. Ectopic expression of SLC5A7 either by overexpression, or uptake of choline efficiently inhibits CRC growth. Examination of the molecular mechanism reveals that SLC5A7 promotes p53 protein expression by directly interacting with and modifying p53 and disrupting the interaction between p53 and MDM2 in wild type p53 CRC cells. Our findings establish the clear correlation between SLC5A7 and tumour growth, providing a novel potential therapeutic target for CRC.
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- 2022
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21. Electricity generation in simulated benthic microbial fuel cell with conductive polyaniline-polypyrole composite hydrogel anode
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Jiyong Zheng, Ye Chen, Qing Wen, Qiu Zhenghui, Yanan Du, Haitao Xu, and Cunguo Lin
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chemistry.chemical_compound ,Materials science ,Microbial fuel cell ,Biocompatibility ,Chemical engineering ,chemistry ,Renewable Energy, Sustainability and the Environment ,Electrode ,Composite number ,Polyaniline ,Internal resistance ,Electrochemistry ,Anode - Abstract
As a sustainable and eco-friendly technology, the benthic microbial fuel cell (BMFC) has been emerged as alternative and potential approach to recover electrical energy by microorganisms, but lower power density and poor long-term life hinder their practical application. Modification of anodic materials is an efficient strategy to solve this problem. Here, a conductive and biocompatible hydrogel electrode, polyaniline-polypyrole-CNTs-Fe3O4 (PANI-PPy-CNTs-Fe3O4) is prepared and applied as anode in a simulated BMFC. The maximum power density of the BMFC with PANI-PPy-CNTs-Fe3O4 hydrogel anode (5901.49 mW/m3) is 1.33, 2.15 and 2.06 times higher than that of PANI-PPy (4413.03 mW/m3), PANI and PPy anodes (2737.12 and 2859.53 mW/m3), respectively. The charge transfer resistance of quaternary hydrogel bioanode in BMFC (3.922 Ω) is much lower than that of the PANI (8.682 Ω), PPy (8.262 Ω) and PANI-PPy (5.772 Ω) hydrogel bioanodes. Moreover, the extracellular electron transfer ability is also enhanced on the composite hydrogel anode, which also exhibits the high biomass. High-throughput sequencing technology indicates that the synergistic effect of bacteria on the quaternary hydrogel made full use of organic matter as available fuel to enable a high electricity-generation anode. Such foregoing mainly ascribed to the composite hydrogel keep the high biocompatibility from components, while the addition of CNTs and Fe3O4 dramatically decreases the internal resistance and provides more electrochemical active surface area on basis of macroporous 3D hydrogel structure. This work explores the composite hydrogel used as anodes to construct high-performance BMFC and provides significant information for the applications of actual BMFCs in the future.
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- 2022
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22. Hierarchical porous biomass-derived carbon framework with ultrahigh surface area for outstanding capacitance supercapacitor
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Ye Chen, Shuyan Gao, He Xu, Liyuan Wang, and Yi Zhang
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Supercapacitor ,Materials science ,chemistry ,Chemical engineering ,Renewable Energy, Sustainability and the Environment ,Diffusion ,Electrode ,chemistry.chemical_element ,Electrochemistry ,Porosity ,Capacitance ,Carbon ,Pseudocapacitance - Abstract
A porous carbon framework is successfully synthesized from lycium chinensis via a novel strategy using melamine matched with KOH as dual-activator. The biomass-derived carbon framework with hierarchical macro-/meso-/micro pores demonstrates an ultrahigh surface area of 3344 m2 g−1 and a sufficient total pore volume of 1.71 cm3 g−1. The porous carbon electrode with optimized structure presents an outstanding electrochemical performance. The specific capacitance reaches 520.0 F g−1 at 1 A g−1 and 291.0 F g−1 at 30 A g−1 with 96.8 % capacitance retention after 10 000 cycles at 30 A g−1. The energy density is also as high as 12.5 W h kg−1 for the electrode. The relationship between optimized structure and excellent performance of carbon materials is deeply explored. The superior electrochemical performance of carbon framework can be ascribed to its hierarchical porosity, ultrahigh surface area, sufficient total pore volume, proper graphitization degree and favorable heteroatom-doping, which will result in the fast ion diffusion, sufficient charge storage as well as the contributed pseudocapacitance. The work provides an effective guidance for synthesizing the superb porous biomass-derived carbon materials for supercapacitor with high performance.
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- 2021
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23. Oxidative Cleavage-Based Three-Dimensional DNA Biosensor for Ratiometric Detection of Hypochlorous Acid and Myeloperoxidase
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Bo Liu, De-Ming Kong, Xiao Jing, Dong-Xia Wang, Jia-Yi Ma, Jing Wang, An-Na Tang, and Dan-Ye Chen
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chemistry.chemical_classification ,biology ,Hypochlorous acid ,Chemistry ,Biosensing Techniques ,DNA ,Hydrogen Peroxide ,Oxidative phosphorylation ,Hypochlorous Acid ,Analytical Chemistry ,Oxidative Stress ,chemistry.chemical_compound ,Enzyme ,Biochemistry ,Myeloperoxidase ,Nucleic acid ,biology.protein ,Biomarker (medicine) ,Biosensor ,Peroxidase - Abstract
Methods to detect and quantify disease biomarkers with high specificity and sensitivity in biological fluids play a key role in enabling clinical diagnosis, including point-of-care testing. Myeloperoxidase (MPO) is an emerging biomarker for the detection of inflammation, neurodegenerative diseases, and cardiovascular disease, where excess MPO can lead to oxidative damage to biomolecules in homeostatic systems. While numerous methods have been developed for MPO analysis, most techniques are challenging in clinical applications due to the lack of amplification methods, high cost, or other practical drawbacks. Enzyme-linked immunosorbent assays are currently used for the quantification of MPO in clinical practice, which is often limited by the availability of antibodies with high affinity and specificity and the significant nonspecific binding of antibodies to the analytical surface. In contrast, nucleic acid-based biosensors are of interest because of their simplicity, fast response time, low cost, high sensitivity, and low background signal, but detection targets are limited to nucleic acids and non-nucleic acid biomarkers are rare. Recent studies reveal that the modification of a genome in the form of phosphorothioate is specifically sensitive to the oxidative effects of the MPO/H2O2/Cl- system. We developed an oxidative cleavage-based three-dimensional DNA biosensor for rapid, ratiometric detection of HOCl and MPO in a "one-pot" method, which is simple, stable, sensitive, specific, and time-saving and does not require a complex reaction process, such as PCR and enzyme involvement. The constructed biosensor has also been successfully used for MPO detection in complex samples. This strategy is therefore of great value in disease diagnosis and biomedical research.
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- 2021
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24. Phosphorylation of transcription factor bZIP21 by MAP kinase MPK6-3 enhances banana fruit ripening
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Jian-ye Chen, Chao-jie Wu, Xuncheng Liu, Wei Wei, Mondher Bouzayen, Li-Sha Zhu, Yu-Fan Guo, Wei Shan, Jian-fei Kuang, Ying-Ying Yang, and Wang-jin Lu
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Crops, Agricultural ,China ,Physiology ,Chemistry ,food and beverages ,Musa ,Ripening ,Promoter ,Plant Science ,Genes, Plant ,Cell biology ,Gene Expression Regulation, Plant ,Transcription (biology) ,Fruit ,Genetics ,Transcriptional regulation ,Phosphorylation ,Protein phosphorylation ,Mitogen-Activated Protein Kinases ,Gene ,Transcription factor ,Research Articles ,Transcription Factors - Abstract
Ripening of fleshy fruits involves both diverse post-translational modifications (PTMs) and dynamic transcriptional reprogramming, but the interconnection between PTMs, such as protein phosphorylation and transcriptional regulation, in fruit ripening remains to be deciphered. Here, we conducted a phosphoproteomic analysis during banana (Musa acuminata) ripening and identified 63 unique phosphopeptides corresponding to 49 proteins. Among them, a Musa acuminata basic leucine zipper transcription factor21 (MabZIP21) displayed elevated phosphorylation level in the ripening stage. MabZIP21 transcript and phosphorylation abundance increased during banana ripening. Genome-wide MabZIP21 DNA binding assays revealed MabZIP21-regulated functional genes contributing to banana ripening, and electrophoretic mobility shift assay, chromatin immunoprecipitation coupled with quantitative polymerase chain reaction, and dual-luciferase reporter analyses demonstrated that MabZIP21 stimulates the transcription of a subset of ripening-related genes via directly binding to their promoters. Moreover, MabZIP21 can be phosphorylated by MaMPK6-3, which plays a role in banana ripening, and T318 and S436 are important phosphorylation sites. Protein phosphorylation enhanced MabZIP21-mediated transcriptional activation ability, and transient overexpression of the phosphomimetic form of MabZIP21 accelerated banana fruit ripening. Additionally, MabZIP21 enlarges its role in transcriptional regulation by activating the transcription of both MaMPK6-3 and itself. Taken together, this study reveals an important machinery of protein phosphorylation in banana fruit ripening in which MabZIP21 is a component of the complex phosphorylation pathway linking the upstream signal mediated by MaMPK6-3 with transcriptional controlling of a subset of ripening-associated genes.
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- 2021
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25. Effects of manganese toxicity on the growth of soybean (Glycine max L.) at the seedling stage
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Ying Liu, Shao Xia Yang, Xiao Hao Li, Ying Bin Xue, Jing Ye Chen, and Han Qiao Hu
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Horticulture ,biology ,chemistry ,Seedling ,Glycine ,Toxicity ,chemistry.chemical_element ,Plant Science ,Stage (hydrology) ,Manganese ,biology.organism_classification - Abstract
Effects of manganese (Mn) toxicity stress on the growth of soybean, the number of Mn spots on leaves and the absorption of iron and magnesium were studied by nutrient solution hydroponics. The results showed that the presence of Mn spots on leaves was the main symptom of Mn toxicity in soybean. When the concentration of exogenous Mn was 25 μmol/l, the leaf generated obvious Mn oxidation spots; when the concentration of exogenous Mn exceeded 50 μmol/l, the growth of soybean was inhibited, and the number of Mn spots increased significantly. With the increase in exogenous Mn concentration, the Mn concentration in the roots, young leaves and old leaves of soybean increased significantly. When the concentration of exogenous Mn reached 200 μmol/l, the number of Mn spots on primary leaves, old leaves and young leaves increased significantly. Although the iron concentration in the roots remained the same, the iron content in the old and young leaves decreased significantly. On the other hand, although Mn toxicity significantly reduced the concentration of magnesium in soybean roots, it increased the concentration of magnesium in old and young leaves. Bangladesh J. Bot. 50(3): 803-811, 2021 (September) Special
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- 2021
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26. Template-assisted polymerization-pyrolysis derived mesoporous carbon anchored with Fe/Fe3C and Fe−NX species as efficient oxygen reduction catalysts for Zn-air battery
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Fengxian Zhang, Ye Chen, Xupo Liu, Yang Liu, and Shuyan Gao
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Materials science ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology ,Nanoparticle ,Electrolyte ,Condensed Matter Physics ,Catalysis ,chemistry.chemical_compound ,Fuel Technology ,Polymerization ,chemistry ,Chemical engineering ,Specific surface area ,Methanol ,Mesoporous material ,Pyrolysis - Abstract
Constructing highly efficient and durable non-noble metal modified carbon catalysts for oxygen reduction reaction (ORR) in the whole pH range is essential for energy conversion devices but still remains a challenge. Herein, the Fe/Fe3C nanoparticles and Fe-NX species anchored on the interconnected mesoporous carbon materials are fabricated through an economical and facile template-assisted polymerization-pyrolysis strategy. The catalyst exhibits unique features with the electronic interaction between Fe/Fe3C and Fe−NX, large specific surface area and high mesoporous structure as well as nitrogen doping in porous carbon skeletons, which can effectively catalyze ORR over the full pH range. In an alkaline electrolyte, the optimized catalyst displays favorable ORR performance with positive onset potential (Eonset = 0.91 V), half-wave potential (E1/2 = 0.83 V), long-term cycles stability and methanol tolerance, exceeding those for the commercial Pt/C. Furthermore, the prepared catalyst could be directly assembled into the alkaline Zn−air battery that exhibits the open-circuit voltage of 1.44 V, high power density of 96.0 mW cm−2 and long-term durability. Therefore, the template-assisted polymerization-pyrolysis strategy provides a promising route for designing high-performance non-noble metal decorated ORR electrocatalysts.
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- 2021
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27. Free-standing MoS2/graphene flexible film as binder-free electrode for enhanced electrochemical performances in lithium-ion half-cells and full-cells
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Ye Chen, Ting Huang, Qiong Xu, Guanghui Yuan, Xinyu Ge, Rui Cao, and Zhaozhe Wang
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Materials science ,Graphene ,General Chemical Engineering ,Composite number ,General Engineering ,General Physics and Astronomy ,Ionic bonding ,chemistry.chemical_element ,Conductivity ,Electrochemistry ,Anode ,law.invention ,Chemical engineering ,chemistry ,law ,Electrode ,General Materials Science ,Lithium - Abstract
A free-standing MoS2–graphene flexible film (MoS2/GN-F) is designed and prepared by a facile vacuum filtration method without using any templates. SEM and TEM images show that the MoS2/GN flower-like particles are self-assembled by MoS2 nanoflakes and graphene nanosheets. Electrochemical performances of the MoS2/GN-F film as anode active material in Lithium-ion batteries (LIBs) are investigated in both MoS2/GN//Li half-cells and MoS2/GN//LiCoO2 full-cells. The MoS2/GN-F sample maintains high reversible discharge capacities of 700.3 mAh g−1 after 100 cycles at 400 mA g−1 in MoS2/GN//Li half-cells. The assembled MoS2/GN-F//LiCoO2 full-cell delivers high initial discharge capacities of 1149.1 mAh g−1. The excellent lithium storage performances of the obtained MoS2/GN-F film can be mainly attributed to the designed novel structure of the composite. The cross-linked graphene nanosheets, the anchoring MoS2 nanoflakes, and the synergistic effects between them make the composite good conductivity, enough buffering space for the volume change, and shortened ionic transport length. This work clearly demonstrates that the MoS2/GN-F film is a promising alternative material for anode in the LIB applications.
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- 2021
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28. Network Pharmacology-Based Analysis on the Action Mechanism of Oleanolic Acid to Alleviate Osteoporosis
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Li-Jie Gao, Qin Li, Ying-Sai Fan, Ye Chen, and Yi Wu
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Mechanism (biology) ,General Chemical Engineering ,General Chemistry ,Computational biology ,Biology ,Article ,GeneCards ,chemistry.chemical_compound ,Metabolic pathway ,Chemistry ,chemistry ,In vivo ,Interaction network ,KEGG ,Signal transduction ,Oleanolic acid ,QD1-999 - Abstract
Oleanolic acid (OA) is a triterpenoid commonly found in plants and has shown extensive pharmaceutical activities. This study aimed to investigate the underlying mechanism of antiosteoporosis (OP) action of OA by utilizing the network pharmacology approach and molecular docking methods. First, the targets of OA were identified using the GeneCards, Stitch, and Swisstarget databases, and the targets related to OP were mined using the NCBI, Genecards, and DisGeNet databases. The overlapped targets of OA and OP were regarded as candidate targets, and the String database was used to obtain the protein–protein interactions among the targets. Then, Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway enrichment pathways of the candidate targets were performed using the DAVID database. In addition, the top 16 targets in the protein interaction network were used for molecular docking. Finally, an animal model constructed using d-galactose-induced oxidative stress and a low-calcium diet with accelerated bone loss was used to verify the in vivo effects of OA on osteoporotic mice. A total of 42 candidate targets for OA to treat OP were obtained. According to the protein–protein interaction network, MAPK1 showed the highest connectivity with other proteins. Additionally, GO analysis identified the top 20 biological processes, 9 cellular components, and top 20 molecular functions. Moreover, the candidate targets were mainly involved in 13 signaling pathways such as TNF signaling pathway, insulin resistance, MAPK signaling pathway, apoptosis, and PI3K-Akt signaling pathways. Furthermore, molecular docking revealed that OA has a high degree of connections with 16 key proteins. In addition, the anti-OP effects of OA are further validated through the in vivo model. Altogether, our study elucidated the candidate targets for OA to alleviate OP, explored the protein–protein interactions and related signaling pathways of the targets, and validated the anti-OP effects of OA. It could provide a better understanding of the action mechanism in OA to treat OP.
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- 2021
29. Heterometal–Organic Cages as Photo-Fenton-like Catalysts
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Dan Li, Yu-Bai Wei, Xiao-Ping Zhou, Xiao-Wei Zhu, Fen-Ling Zhuang, Shu Zhou, and Zi-Ye Chen
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inorganic chemicals ,Metal ions in aqueous solution ,Radical ,Supramolecular chemistry ,Photochemistry ,Catalysis ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Imidazolate ,Rhodamine B ,Methyl orange ,Physical and Theoretical Chemistry ,Methylene blue - Abstract
Metal-organic cages, a class of supramolecular containers constructed by the self-assembly of metal ions and organic ligands, show great promise as catalytic agents. In this work, we designed and synthesized a series of rhombic dodecahedral Ni-Cu heterometal imidazolate cages (Ni8Cu6L24) that can act as highly active photo-Fenton-like catalysts. These cages possess a high ability to generate hydroxyl radicals (•OH) under visible light in the presence of H2O2, which can rapidly degrade organic pollutants (e.g., rhodamine B, methylene blue, and methyl orange) into CO2 and H2O. Besides, they are robust catalysts, with high catalytic activity and reusability under conditions in high H2O2 concentration, providing potentially advanced materials for degrading persistent organic pollutants.
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- 2021
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30. Genome-wide identification of altered RNA m6A profiles in vascular tissue of septic rats
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Zhujun Shen, Hongzhi Xie, Mu-Wen Nie, Ruo-Lan Xiang, Ye-Chen Han, and Yining Wang
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Aging ,Competing endogenous RNA ,Microarray analysis techniques ,MRNA modification ,RNA ,Cell Biology ,Organic anion transmembrane transporter activity ,Biology ,Cell biology ,chemistry.chemical_compound ,chemistry ,Intensive care ,N6-Methyladenosine ,KEGG - Abstract
Sepsis is the leading cause of death in hospital intensive care units. In light of recent studies showing that variations in N6-methyladenosine (m6A) levels in different RNA transcripts influence inflammatory responses, we evaluated the m6A profiles of rat aortic mRNAs and lncRNAs after lipopolysaccharide (LPS)-induced sepsis. LC-MS-based mRNA modification analysis showed that global m6A levels were significantly decreased in aortic tissue of rats injected intraperitoneally with LPS. This finding was consistent with downregulated expression of METTL3 and WTAP, two members of the m6A writer complex, in LPS-exposed aortas. Microarray analysis of m6A methylation indicated that 40 transcripts (31 mRNAs and 9 lncRNAs) were hypermethylated, while 223 transcripts (156 mRNAs and 67 lncRNAs) were hypomethylated, in aortic tissue from LPS-treated rats. On GO and KEGG analyses, 'complement and coagulation cascades', 'transient receptor potential channels', and 'organic anion transmembrane transporter activity' were the major biological processes modulated by the differentially m6A methylated mRNAs. In turn, competing endogenous RNA network analysis suggested that decreased m6A levels in lncRNA-XR_343955 may affect the inflammatory response through the cell adhesion molecule pathway. Our data suggest that therapeutic modulation of the cellular m6A machinery may be useful to preserve vascular integrity and function during sepsis.
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- 2021
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31. Endothelium‐derived hydrogen sulfide acts as a hyperpolarizing factor and exerts neuroprotective effects via activation of large‐conductance Ca 2+ ‐activated K + channels
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Ji-Yue Wen, Zhi-Wu Chen, Ye Chen, Jing-Si Duan, Fang Zhang, Shuo Chen, Yi-Fei Fan, Zi-Yao Ma, Yang Zhang, Wei-Ming Xie, and Jie Zhang
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Pharmacology ,Voltage-dependent calcium channel ,Chemistry ,Calcium channel ,Membrane hyperpolarization ,Iberiotoxin ,Neuroprotection ,Cell biology ,Electrophysiology ,medicine.anatomical_structure ,cardiovascular system ,medicine ,Neuron ,Ion channel - Abstract
BACKGROUND AND PURPOSE Endothelium-derived hyperpolarizing factor (EDHF) has been suggested as a therapeutic target for vascular protection against ischaemic brain injury. However, the molecular entity of EDHF and its action on neurons remains unclear. This study was undertaken to demonstrate whether the hydrogen sulfide (H2 S) acts as EDHF and exerts neuroprotective effect via large-conductance Ca2+ -activated K+ (BKCa /KCa 1.1) channels. EXPERIMENTAL APPROACH The whole-cell patch-clamp technology was used to record the changes of BKCa currents in rat neurons induced by EDHF. The cerebral ischaemia/reperfusion model of mice and oxygen-glucose deprivation/reoxygenation (OGD/R) model of neurons were used to explore the neuroprotection of EDHF by activating BKCa channels in these neurons. KEY RESULTS Increases of BKCa currents and membrane hyperpolarization in hippocampal neurons induced by EDHF could be markedly inhibited by BKCa channel inhibitor iberiotoxin or endothelial H2 S synthase inhibitor propargylglycine. The H2 S donor, NaHS-induced BKCa current and membrane hyperpolarization in neurons were also inhibited by iberiotoxin, suggesting that H2 S acts as EDHF and activates the neuronal BKCa channels. Besides, we found that the protective effect of endothelium-derived H2 S against mice cerebral ischaemia/reperfusion injury was disrupted by iberiotoxin. Importantly, the inhibitory effect of NaHS or BKCa channel opener on OGD/R-induced neuron injury and the increment of intracellular Ca2+ level could be inhibited by iberiotoxin but enhanced by co-application with L-type but not T-type calcium channel inhibitor. CONCLUSION AND IMPLICATIONS Endothelium-derived H2 S acts as EDHF and exerts neuroprotective effects via activating the BKCa channels and then inhibiting the T-type calcium channels in hippocampal neurons.
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- 2021
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32. Solvent Effects on Linear and Multi-branched Bithiazole-based Derivatives Fluorescence Studied by Steady-state and Time-resovled Spectroscopy
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Xiang Li, Jianli Hua, Minghao Ni, Ye Chen, Nannan He, Fuwen Shi, Bo Li, and Zhiquan Wang
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chemistry.chemical_compound ,Chemistry ,Excited state ,Single bond ,Physical and Theoretical Chemistry ,Solvent effects ,Time-resolved spectroscopy ,Triphenylamine ,Triple bond ,Photochemistry ,Spectroscopy ,Acceptor - Abstract
Steady-state absorption, emission, and time-resolved spectroscopy were utilized to study the dynamics of excited states of linear and multi-branched bithiazole derivatives in different solvents at room temperature. In the studied compounds, triphenylamine and bithiazole groups act as donor and acceptor, respectively. BTZ-I and II have similar linear molecular structures, while BTZ-III and BTZ-IV have multi-branched structures. The difference is that the donor and acceptor units are connected by a single bond or a triple bond, respectively. With increase in solvent polarity, the fluorescence spectra exhibit a red shift and the fluorescence lifetime increases. Our results suggest there is intra-molecular charge transfer (ICT) processes in these four samples.
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- 2021
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33. Ethoxylation of Phenols Catalyzed by <scp>Metal‐Free</scp> Lewis Pairs: Living/Controlled Polymerization in a <scp>Slow‐Initiation</scp> Mode †
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Ye Chen, Qiang Zhang, Yubo Zhou, and Junpeng Zhao
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Ethoxylation ,chemistry.chemical_compound ,Polymerization ,Chemistry ,Organocatalysis ,Polymer chemistry ,Phenol ,General Chemistry ,Phenols ,Lewis acids and bases ,Ring-opening polymerization ,Catalysis - Published
- 2021
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34. A Multidimensional Mass Spectrometry-Based Workflow for De Novo Structural Elucidation of Oligosaccharides from Polysaccharides
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Eshani Nandita, Ace G. Galermo, Ye Chen, Garret Couture, Carlito B. Lebrilla, Matthew J. Amicucci, Nikita P. Bacalzo, and Juan Jose Castillo
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chemistry.chemical_classification ,Workflow ,Chromatography ,chemistry ,Structural Biology ,Monosaccharide ,Glycosidic bond ,Whole food ,Sequence (biology) ,Oligosaccharide ,Mass spectrometry ,Polysaccharide ,Spectroscopy - Abstract
Carbohydrates play essential roles in a variety of biological processes that are dictated by their structures. However, characterization of carbohydrate structures remains extremely difficult and generally unsolved. In this work, a de novo mass spectrometry-based workflow was developed to isolate and structurally elucidate oligosaccharides to provide sequence, monosaccharide compositions, and glycosidic linkage positions. The approach employs liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based methods in a 3-dimensional concept: one high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF MS) analysis for oligosaccharide sequencing and two ultra high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-QqQ MS) analyses on fractionated oligosaccharides to determine their monosaccharides and linkages compositions. The workflow was validated by applying the procedure to maltooligosaccharide standards. The approach was then used to determine the structures of oligosaccharides derived from polysaccharide standards and whole food products. The integrated LC-MS workflow will reveal the in-depth structures of oligosaccharides.
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- 2021
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35. Nanomechanical sensor for rapid and ultrasensitive detection of tumor markers in serum using nanobody
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Kainan Mei, Wenjie Wu, Shangquan Wu, Tianhao Yan, Jianye Wang, Depeng Rao, Qingchuan Zhang, Ye Chen, and Yu Wang
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Early cancer ,nanobody-based biosensor ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,adsorption-induced inactivation ,Thiol group ,stress enhancement ,General Materials Science ,Electrical and Electronic Engineering ,Binding site ,Receptor ,Tumor marker ,Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Orders of magnitude (mass) ,0104 chemical sciences ,tumor markers ,Covalent bond ,Biophysics ,early cancer detection ,0210 nano-technology ,Research Article ,Macromolecule - Abstract
Early cancer diagnosis requires ultrasensitive detection of tumor markers in blood. To this end, we develop a novel microcantilever immunosensor using nanobodies (Nbs) as receptors. As the smallest antibody (Ab) entity comprising an intact antigen-binding site, Nbs achieve dense receptor layers and short distances between antigen-binding regions and sensor surfaces, which significantly elevate the generation and transmission of surface stress. Owing to the inherent thiol group at the C-terminus, Nbs are covalently immobilized on microcantilever surfaces in directed orientation via one-step reaction, which further enhances the stress generation. For microcantilever-based nanomechanical sensor, these advantages dramatically increase the sensor sensitivity. Thus, Nb-functionalized microcantilevers can detect picomolar concentrations of tumor markers with three orders of magnitude higher sensitivity, when compared with conventional Ab-functionalized microcantilevers. This proof-of-concept study demonstrates an ultrasensitive, label-free, rapid, and low-cost method for tumor marker detection. Moreover, interestingly, we find Nb inactivation on sensor interfaces when using macromolecule blocking reagents. The adsorption-induced inactivation is presumably caused by the change of interfacial properties, due to binding site occlusion upon complex coimmobilization formations. Our findings are generalized to any coimmobilization methodology for Nbs and, thus, for the construction of high-performance immuno-surfaces. Electronic Supplementary Material Supplementary material (experimental section, HER2 detection using anti-HER2-mAb-functionalized microcantilevers) is available in the online version of this article at 10.1007/s12274-021-3588-4.
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- 2021
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36. Cobalt-Based Metal–Organic Cages for Visible-Light-Driven Water Oxidation
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Jie-Yi Zhou, Zi-Hao Long, Dan Li, Xue-Zhi Wang, Xusheng Wang, Xiao-Ping Zhou, and Zi-Ye Chen
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010405 organic chemistry ,Oxygen evolution ,chemistry.chemical_element ,010402 general chemistry ,Photochemistry ,Electrochemistry ,01 natural sciences ,Oxygen ,0104 chemical sciences ,Catalysis ,Inorganic Chemistry ,Metal ,Electron transfer ,chemistry ,visual_art ,visual_art.visual_art_medium ,Physical and Theoretical Chemistry ,Cobalt ,Visible spectrum - Abstract
Water oxidation to molecular oxygen is indispensable but a challenge for splitting H2O. In this work, a series of Co-based metal-organic cages (MOCs) for photoinduced water oxidation were prepared. MOC-1 with both bis(μ-oxo) bridged dicobalt and Co-O (O from H2O) displays catalytic activity with an initial oxygen evolution rate of 80.4 mmol/g/h and a TOF of 7.49 × 10-3 s-1 in 10 min. In contrast, MOC-2 containing only Co-O (O from H2O) in the structure results in a lower oxygen evolution rate (40.8 mmol/g/h, 4.78 × 10-3 s-1), while the amount of oxygen evolved from the solution of MOC-4 without both active sites is undetectable. Isotope experiments with or without H218O as the reactant successfully demonstrate that the molecular oxygen was produced from water oxidation. Photophysical and electrochemical studies reveal that photoinduced water oxidation initializes via electron transfer from the excited [Ru(bpy)3]2+* to Na2S2O8, and then, the cobalt active sites further donate electrons to the oxidized [Ru(bpy)3]3+ to drive water oxidation. This proof-of-concept study indicates that MOCs can work as potential efficient catalysts for photoinduced water oxidation.
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- 2021
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37. Pd‐Catalyzed Amidation of Silyl Enol Ethers With CO and Azides via an Isocyanate Intermediate
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Zheng-Yang Gu, Ye Chen, Ji-Bao Xia, and Yi-Qian Jiang
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chemistry.chemical_compound ,chemistry ,Silylation ,Organic Chemistry ,Polymer chemistry ,Azide ,Carbonylation ,Enol ,Isocyanate ,Catalysis - Published
- 2021
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38. H2S protects hippocampal neurons against hypoxia-reoxygenation injury by promoting RhoA phosphorylation at Ser188
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Zhiwu Chen, Ye Chen, and Jiyue Wen
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0301 basic medicine ,Cancer Research ,RHOA ,Immunology ,Neuroprotection ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,ROCK2 ,Protein kinase A ,RC254-282 ,ATP synthase ,biology ,QH573-671 ,Chemistry ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Cell Biology ,Transfection ,equipment and supplies ,In vitro ,Cell biology ,030104 developmental biology ,biology.protein ,Phosphorylation ,Cytology ,030217 neurology & neurosurgery - Abstract
Inhibition of RhoA-ROCK pathway is involved in the H2S-induced cerebral vasodilatation and H2S-mediated protection on endothelial cells against oxygen-glucose deprivation/reoxygenation injury. However, the inhibitory mechanism of H2S on RhoA-ROCK pathway is still unclear. The aim of this study was to investigate the target and mechanism of H2S in inhibition of RhoA/ROCK. GST-RhoAwild and GST-RhoAS188A proteins were constructed and expressed, and were used for phosphorylation assay in vitro. Recombinant RhoAwild-pEGFP-N1 and RhoAS188A-pEGFP-N1 plasmids were constructed and transfected into primary hippocampal nerve cells (HNCs) to evaluate the neuroprotective mechanism of endothelial H2S by using transwell co-culture system with endothelial cells from cystathionine-γ-lyase knockout (CSE−/−) mice and 3-mercaptopyruvate sulfurtransferase knockout (3-MST−/−) rats, respectively. We found that NaHS, exogenous H2S donor, promoted RhoA phosphorylation at Ser188 in the presence of cGMP-dependent protein kinase 1 (PKG1) in vitro. Besides, both exogenous and endothelial H2S facilitated the RhoA phosphorylation at Ser188 in HNCs, which induced the reduction of RhoA activity and membrane transposition, as well as ROCK2 activity and expression. To further investigate the role of endothelial H2S on RhoA phosphorylation, we detected H2S release from ECs of CSE+/+ and CSE−/− mice, and 3-MST+/+ and 3-MST−/− rats, respectively, and found that H2S produced by ECs in the culture medium is mainly catalyzed by CSE synthase. Moreover, we revealed that both endothelial H2S, mainly catalyzed by CSE, and exogenous H2S protected the HNCs against hypoxia-reoxygenation injury via phosphorylating RhoA at Ser188.
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- 2021
39. High Precision Adaptive Robust Neural Network Control of a Servo Pneumatic System
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Ye Chen, Guoliang Tao, and Hao Liu
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adaptive robust control ,neural network ,pneumatic systems ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this paper, an adaptive robust neural network controller (ARNNC) is synthesized for a single-rod pneumatic actuator to achieve high tracking accuracy without knowing the bounds of the parameters and disturbances. The ARNNC control framework integrates adaptive control, robust control, and neural network control intelligently. Adaptive control improves the precision of dynamic compensation with parametric estimation, and robust control attenuates the effect of unmodeled dynamics and unknown disturbances. In reality, the unmodeled dynamics of the complicated pneumatic systems and unpredictable disturbances in working conditions affect the tracking precision. However, these cannot be expressed as an exact formula. Therefore, the real-time learning radial basis function (RBF) neural network component is considered for better compensation of unmodeled dynamics, random disturbances, and estimation errors of the adaptive control. Although the bounds of the parameters and disturbances for the pneumatic systems are unknown, the prescribed transient performance and final tracking accuracy of the proposed method can be still achieved with fictitious bounds. Asymptotic tracking performance can be acquired under the provided circumstance. The comparative experiments with a pneumatic cylinder driven by proportional direction valve illustrate the effectiveness of the proposed ARNNC as shown by a high tracking accuracy is achieved.
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- 2019
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40. Noncovalent Protection for Direct Synthesis of α-Amino-ω-hydroxyl Poly(ethylene oxide)
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David Pahovnik, Junpeng Zhao, Guangzhao Zhang, Pengfei Zhang, Ema Žagar, Shan Liu, and Ye Chen
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Ethylene Oxide ,Polymers and Plastics ,Chemistry ,Organic Chemistry ,Oxide ,Polyethylene Glycols ,Polymerization ,Molecular Weight ,Inorganic Chemistry ,chemistry.chemical_compound ,Polymer chemistry ,Materials Chemistry ,Amines ,Poly ethylene - Abstract
The synthesis of poly(ethylene oxide) (PEO) with amino end group, a key functionality for PEGylation, is a long-standing challenge. Multistep routes based on postmodification or covalent protection have been adopted to circumvent ethoxylation of the amino group by ethylene oxide (EO). Here, we report a noncovalent protection strategy for one-step synthesis of PEO amine. An amino (di)alcohol is mixed with a small amount of mild phosphazene base and excess triethylborane (Et
- Published
- 2021
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41. Study on the Slow-Release Mometasone Furoate Injection of PLGA for the Treatment of Knee Arthritis
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Ju Liu, Ming Wang, Yutong Liang, Ye Chen, Yang Wang, Shi Ding, Jiaojiao Zhang, and Xinghua Zhao
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Male ,Chromatography ,Chemistry ,Arthritis ,Pharmaceutical Science ,Mometasone furoate ,Biodegradable polymer ,Microspheres ,Rats ,Rats, Sprague-Dawley ,PLGA ,chemistry.chemical_compound ,Pharmacokinetics ,Solvent evaporation ,In vivo ,Delayed-Action Preparations ,Pharmacodynamics ,Emulsion ,medicine ,Animals ,Particle Size ,Mometasone Furoate ,Polyglycolic Acid ,medicine.drug - Abstract
Purpose: The purpose of this study is to develop a new PLGA based formulation for microspheres, which aims to release mometasone furoate for one month, so as to improve compliance. Methods: The microspheres containing mometasone furoate were prepared by oil in water emulsion and solvent evaporation. The microspheres were characterized by surface morphology, shape, size and encapsulation efficiency. The release in vitro was studied in 37°C phosphate buffer, and in vivo, pharmacodynamics and preliminary safety evaluation were conducted in male Sprague Dawley rats. Results: The morphology results showed that the microspheres have a smooth surface, spherical shape and an average diameter of 2.320-5.679μm. The encapsulation efficiency of the microspheres loaded with mometasone furoate was in the range of 53.1% to 95.2%, and the encapsulation efficiency of the microspheres could be greatly affected by the proportion of oil phase to the water phase and other formulation parameters. In vitro release kinetics revealed that drug release from microspheres was through non-Fick's diffusion and PLGA polymer erosion. Pharmacokinetic data showed that the initial release of microspheres was small and then sustained. The results of the pharmacodynamics study fully proved the long-term effectiveness of mometasone furoate microspheres. The results of in vivo safety evaluation showed that the preparation system possessed good in vivo safety. Conclusion: This study shows that the microspheres prepared in this study have sufficient ability to stable drug release at least for 35 days, with good efficacy and high safety. In addition, mometasone furoate can be used as a potential candidate drug for 35 days long-term injection.
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- 2021
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42. The Variation of Microbial (Methanotroph) Communities in Marine Sediments Due to Aerobic Oxidation of Hydrocarbons
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Xingliang He, Qingguo Meng, Feng Li, Changling Liu, Ye Chen, Jing Li, Nengyou Wu, and Hao Xiluo
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chemistry.chemical_classification ,Methanotroph ,biology ,Chemistry ,Terrigenous sediment ,Methane monooxygenase ,Sediment ,Ocean Engineering ,04 agricultural and veterinary sciences ,Oceanography ,biology.organism_classification ,Methane ,chemistry.chemical_compound ,Hydrocarbon ,Environmental chemistry ,Methylocystaceae ,040102 fisheries ,biology.protein ,0401 agriculture, forestry, and fisheries ,Bacteria - Abstract
Methanotrophs in marine sediments and overlying water attenuate the emissions of methane into the atmosphere and thus play an important role for the global cycle of this greenhouse gas. However, gas released from natural hydrocarbon seeps are not pure methane but commonly mixed hydrocarbons. Currently, how methanotrophic bacteria behave in the co-presence of methane and heavier hydrocarbons remains unknown. In this paper, the bacteria were cultured aerobically in fresh sediment samples (collected from Bohai Bay in eastern China) at 28°C under the atmospheres of pure methane and methane+ethane+propane mixed gas, respectively. The prevailing terrigenous n-alkanes and fatty acids in the original sediment samples varied consistently after incubations, confirming the proceeding of aerobic bacterial activities. The real-time quantitative PCR assay and sequencing of the 16S rRNA and particulate methane monooxygenase (pmoA) genes revealed the changes of microbe communities to a methanotroph-dominating structure after incubations. Particularly, after incubations the family Methylococcaceae (type I methanotrophs) became dominant with proportions higher than 40%, whereas Methylocystaceae (type II methanotrophs) nearly disappeared in all incubated samples. Moreover, the species of methanotrophs from the samples treated with pure methane were dominated by Methylobacter luteus, whereas Methylobacter whittenburyi took the predominant proportion in the samples treated with mixed gas. The phenomenon suggests that some methanotrophs may also utilize ethane and propane. Collectively, this study may help to gain a better understanding of the effects and contributions of microbial activities in marine hydrocarbon seep ecosystems.
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- 2021
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43. Enantioselective environmental behavior of the chiral fungicide mandipropamid in four types of Chinese soil
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Deyu Hu, Dan Chen, Jiahua Han, Kankan Zhang, Ye Chen, and Zhengyi Liu
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Fungicide ,Chemistry ,Environmental behavior ,Enantioselective synthesis ,Soil Science ,Organic chemistry - Published
- 2021
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44. Determination, dissipation dynamics, terminal residues and dietary risk assessment of thiophanate‐methyl and its metabolite carbendazim in cowpeas collected from different locations in China under field conditions
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Zhengyi Liu, Guangqian Yang, Jiahua Han, Ye Chen, Dan Chen, Tingting Lan, Kankan Zhang, and Jianmin Li
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China ,030309 nutrition & dietetics ,Metabolite ,Food Contamination ,Biology ,Toxicology ,03 medical and health sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,0303 health sciences ,Residue (complex analysis) ,Nutrition and Dietetics ,Carbendazim ,Dietary risk ,Vigna ,Pesticide Residues ,food and beverages ,Sowing ,04 agricultural and veterinary sciences ,Thiophanate ,040401 food science ,Fungicides, Industrial ,Fungicide ,Kinetics ,chemistry ,Seeds ,Thiophanate-methyl ,Benzimidazoles ,Carbamates ,Agronomy and Crop Science ,Food Science ,Biotechnology ,Field conditions - Abstract
Background Thiophanate-methyl and its metabolite carbendazim are broad-spectrum fungicides used on many crops. The residues of these chemicals could result in potential environmental and human health problems. Therefore, investigations of the dissipation and residue behaviors of thiophanate-methyl and its metabolite carbendazim on cowpeas and associated dietary risk assessments are essential for the safety of agricultural products. Results A simple analytical approach using liquid chromatography with tandem mass spectrometry was developed and validated for the determination of thiophanate-methyl and carbendazim concentrations in cowpeas. Good linearity (R2 > 0.998) was obtained, and the recoveries and relative standard deviations were 80.0%-104.7% and 1.4%-5.2%, respectively. The dissipation rates of thiophanate-methyl, carbendazim and total carbendazim were high (half-lives of 1.61-2.46 days) and varied in the field cowpea samples because of the different weather conditions and planting patterns. Based on the definition of thiophanate-methyl, the terminal residues of total carbendazim in cowpea samples were below the maximum residue limits set by Japan for other legumes. The acute and chronic risk quotients of three analytes were 0.0%-27.6% in cowpea samples gathered from all terminal residue treatments, which were below 100%. Conclusion An optimized approach for detecting thiophanate-methyl and carbendazim in cowpeas was applied for the investigation of field-trial samples. The potential acute and chronic dietary risks of thiophanate-methyl, carbendazim and total carbendazim to the health of Chinese consumers were low. These results could guide the safe and proper use of thiophanate-methyl in cowpeas and offer data for the dietary risk assessment of thiophanate-methyl in cowpeas. This article is protected by copyright. All rights reserved.
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- 2021
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45. Blast-induced temporal alterations in blood–brain barrier properties in a rodent model
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Rania Abutarboush, Ming Gu, Stephen T. Ahlers, Usmah Kawoos, Jonathan K. Statz, Ye Chen, and Samantha Y. Goodrich
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Time Factors ,Science ,Explosions ,Gene Expression ,Rodentia ,Molecular neuroscience ,Occludin ,Blood–brain barrier ,Permeability ,Article ,Blast Injuries ,In vivo ,Brain Injuries, Traumatic ,Parenchyma ,medicine ,Animals ,Aquaporin 4 ,Tight Junction Proteins ,Multidisciplinary ,Tight junction ,Chemistry ,Extravasation ,Extracellular Matrix ,Rats ,Disease Models, Animal ,medicine.anatomical_structure ,Blood-Brain Barrier ,Astrocytes ,Biophysics ,cardiovascular system ,Medicine ,Disease Susceptibility ,Biomarkers ,Immunostaining ,Intravital microscopy - Abstract
The consequences of blast-induced traumatic brain injury (bTBI) on the blood–brain barrier (BBB) and components of the neurovascular unit are an area of active research. In this study we assessed the time course of BBB integrity in anesthetized rats exposed to a single blast overpressure of 130 kPa (18.9 PSI). BBB permeability was measured in vivo via intravital microscopy by imaging extravasation of fluorescently labeled tracers (40 kDa and 70 kDa molecular weight) through the pial microvasculature into brain parenchyma at 2–3 h, 1, 3, 14, or 28 days after the blast exposure. BBB structural changes were assessed by immunostaining and molecular assays. At 2–3 h and 1 day after blast exposure, significant increases in the extravasation of the 40 kDa but not the 70 kDa tracers were observed, along with differential reductions in the expression of tight junction proteins (occludin, claudin-5, zona occluden-1) and increase in the levels of the astrocytic water channel protein, AQP-4, and matrix metalloprotease, MMP-9. Nearly all of these measures were normalized by day 3 and maintained up to 28 days post exposure. These data demonstrate that blast-induced changes in BBB permeability are closely coupled to structural and functional components of the BBB.
- Published
- 2021
46. Durable and Flexible Bio-assembled RGO-BC/BC Bilayer Electrodes for Pressure Sensing
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Zhuotong Wu, Fangyi Guan, Jin Mengtian, Shiyan Chen, Zhiliang Han, Ye Chen, and Huaping Wang
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Materials science ,Polymers and Plastics ,business.industry ,Graphene ,Materials Science (miscellaneous) ,Capacitive sensing ,Bilayer ,Pressure sensor ,Electronic, Optical and Magnetic Materials ,law.invention ,chemistry.chemical_compound ,chemistry ,Bacterial cellulose ,law ,Nanofiber ,Electrode ,Materials Chemistry ,Optoelectronics ,business ,Layer (electronics) - Abstract
The new generation of electronics tends to be well-performed, facile and environmentally friendly. Here, we report a bio-assembled sensitive pressure senor based on reduced graphene oxide-bacterial cellulose/bacterial cellulose (RGO-BC/BC) bilayer films, integrated by bacteria in one step. The advantage of this integration is that there is strong nanofiber connection between the conductive RGO-BC and insulative highly compressible porous BC layer, which confers RGO-BC/BC film electrode with good robustness, tailorability, flexibility and wearability. Without extra bonding-interface or postprocessing, the RGO-BC/BC bilayer films could be directly assembled into pressure sensing devices. Ascribed from the good reversible compressibility of the BC layer and incorporated bilayer structure, the pressure sensor performs good sensitivity and excellent durability and bending stability. The facile sensitive capacitive sensor could monitor the human hand or finger motion in real time. The sensing array is able to detect the spatial distribution of pressure mounted in the flat plane as well as curved surface of human body, succeeding in the correction of human walking posture for health care. The e-skins are potential in wearable electronics, artificial intelligence, soft robots, healthcare etc.
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- 2021
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47. Persistence, mobility, and leaching risk of flumioxazin in four Chinese soils
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Ye Chen, Dan Chen, Jiahua Han, Kankan Zhang, Zhengyi Liu, and Deyu Hu
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chemistry.chemical_classification ,Stratigraphy ,Microorganism ,04 agricultural and veterinary sciences ,010501 environmental sciences ,complex mixtures ,01 natural sciences ,Persistence (computer science) ,chemistry ,Environmental chemistry ,Soil water ,040103 agronomy & agriculture ,Cation-exchange capacity ,0401 agriculture, forestry, and fisheries ,Organic matter ,Leaching (agriculture) ,Water content ,Groundwater ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
Flumioxan was used to control annual broad-leaved and dicotyledonous weeds. Considering the limited information available, comprehensive investigation of persistence and mobility of flumioxazin in Chinese soil is very important. The degradation, adsorption-desorption, mobility, and leaching risk of flumioxazin in four Chinese soils were investigated under laboratory conditions. The degradation rates of flumioxazin, which correlated with soil moisture, microorganisms, organic matter and pH, were 8.2−50.6 days in the four soils under different conditions. Microorganisms influenced these rates greatly, with half-lives increasing 1.67−2.39-fold. Three possible metabolites were detected by ultrahigh-performance liquid chromatography with high-resolution mass spectrometry, and the metabolic pathways were cleavage of the imide and amide linkages and opening of the cyclic imide. The adsorption capacity of flumioxazin in soil was strongly positively correlated with the soil’s cation exchange capacity (CEC) and organic matter (OM) content, which had correlation coefficients > 0.83. Negative and positive desorption hysteresis effects were observed in Guizhou soil and the other three soils, respectively, which might be related to the different soil constitutions. The mobility was relatively weak in the four Chinese soils and negatively related to CEC and OM content, with correlation coefficients > 0.86. Moreover, the leaching risk of flumioxazin was uncertain for the underground water. The results indicated that flumioxazin was a low-risk herbicide and could be used to evaluate the environmental fate and risk of flumioxazin in soil.
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- 2021
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48. Improvement of grain growth and composition distribution of Cu2ZnSn(S,Se)4 by using chloride-based precursor solution
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Xiatong Qin, Pingxiong Yang, Bin Xu, Junhao Chu, Xiaoshuang Lu, Ye Chen, Yulin Liu, and Lin Sun
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Fabrication ,Materials science ,Renewable Energy, Sustainability and the Environment ,020209 energy ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Chloride ,Copper ,Grain size ,law.invention ,Grain growth ,Crystallinity ,chemistry ,Chemical engineering ,law ,Yield (chemistry) ,Solar cell ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,General Materials Science ,0210 nano-technology ,medicine.drug - Abstract
Excellent crystallinity and uniform composition distribution of the Cu2ZnSn(S,Se)4 (CZTSSe) absorber are indispensable factors for the fabrication of photovoltaic device with excellent performance. Here, a facile and effective method is developed to improve the composition uniformity of CZTSSe absorber. It is inspiring that by replacing the acetates with chlorides as the solutes in the precursor solution, the issue of the composition non-uniformity especially for the distribution of Cu and Sn, which is ascribed to the rich-carbon in the acetate-based CZTSSe absorber, is able to be avoided. Due to less organic residues and composition uniformity, the grain size and the crystallinity of absorber could be significantly enhanced, and the photovoltaic performance of chloride-based CZTSSe solar cell is improved remarkably. Furthermore, substituting CuCl2 with CuCl as the copper source in the precursor solution is able to obtain a stable solution, and the quality of CZTSSe absorber is further improved. As a consequence, 8.48% efficient CZTSSe solar cell has been yield.
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- 2021
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49. F. prausnitzii and its supernatant increase SCFAs-producing bacteria to restore gut dysbiosis in TNBS-induced colitis
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Xue Guo, Yongjian Zhou, Ye Chen, Jing Xu, Youlian Zhou, Haoming Xu, Yuqiang Nie, and Hailan Zhao
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lcsh:Biotechnology ,Biophysics ,lcsh:QR1-502 ,Faecalibacterium prausnitzii ,Gut microbiota ,Gut flora ,Applied Microbiology and Biotechnology ,Inflammatory bowel disease ,digestive system ,lcsh:Microbiology ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,lcsh:TP248.13-248.65 ,medicine ,Colitis ,F. prausnitzii ,030304 developmental biology ,0303 health sciences ,biology ,Chemistry ,Supernatant ,Short-chain fatty acid ,Short chain fatty acid ,Bacteroidetes ,biology.organism_classification ,medicine.disease ,Original Article ,030211 gastroenterology & hepatology ,Dysbiosis ,Bacteria - Abstract
An increasing number of studies have shown that Faecalibacterium prausnitzii (F. prausnitzii) is a promising anti-inflammatory bacterium that colonizes in the gut and that gut microbiota dysbiosis plays an important role in the pathogenesis of inflammatory bowel disease (IBD). In this study, we report the gut microbiota profile of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis mice treated with F. prausnitzii and its supernatant on the basis of high-throughput sequencing. We interestingly found that both F. prausnitzii and its metabolites exerted protective effects against colitis in mice, which ameliorated gut dysbiosis, with an increase in bacterial diversity and the abundance of short-chain fatty acid (SCFA)-producing bacteria and a decrease in serum TNF-α and the abundance of Proteinbacteria, Acidobacteria, and Bacteroidetes. These findings will provide further evidence of the anti-inflammatory effect of F. prausnitzii, which presents therapeutic potential for IBD treatment.
- Published
- 2021
50. Zwitterionic and hydrophilic polyelectrolyte/metal ion anti-fouling layersviacovalent and coordination bonds for reverse osmosis membranes
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Meng-Ying Jiang, Li-Ye Chen, Qian Zou, Pei-Gen Fu, Si-Wei Xiong, and Jing-Gang Gai
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Fouling ,Chemistry ,Membrane fouling ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Polyelectrolyte ,Membrane technology ,Contact angle ,Membrane ,020401 chemical engineering ,Chemical engineering ,Covalent bond ,Materials Chemistry ,General Materials Science ,0204 chemical engineering ,0210 nano-technology ,Reverse osmosis - Abstract
Reverse osmosis (RO) membrane technology, as an effective and eco-friendly method, has been widely used for seawater desalination and sewage treatment. However, RO membranes inevitably suffer serious organic and biological fouling during operation. Herein, we fabricated a hydrophilic anti-fouling layer on the RO membrane surface through the synergistic effect of covalent bonds and coordination bonds. Polyethyleneimine (PEI) and polyaspartic acid (PASP) are assembled onto the RO membrane surface successively. Fe(III) is utilized to induce further cross-linking for fabricating the PEI/PASP/Fe layer. The modified membranes exhibit superior hydrophilicity, whose water contact angle declines from 86.7° to 23.6°. In addition, the water flux of the PEI/PASP/Fe membrane increases by 45.8% with an excellent desalting property. Long-term, multi-cycle membrane fouling experiments demonstrate that the modified membrane manifests not only a lower flux loss rate (DRt) but also a higher flux recovery rate (FRR). This means that the hydrophilic layer modified membranes show excellent separation performance even under severe environments, which is expected to boost the anti-fouling research in the membrane field.
- Published
- 2021
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