832 results on '"Jie Jiang"'
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2. Exfoliation procedure-dependent optical properties of solution deposited MoS2 films
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Robert T. Busch, Lirong Sun, Drake Austin, Jie Jiang, Paige Miesle, Michael A. Susner, Benjamin S. Conner, Ali Jawaid, Shannon T. Becks, Krishnamurthy Mahalingam, Michael A. Velez, Riccardo Torsi, Joshua A. Robinson, Rahul Rao, Nicholas R. Glavin, Richard A. Vaia, Ruth Pachter, W. Joshua Kennedy, Jonathan P. Vernon, and Peter R. Stevenson
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemistry ,QD1-999 - Abstract
Abstract The development of high-precision large-area optical coatings and devices comprising low-dimensional materials hinges on scalable solution-based manufacturability with control over exfoliation procedure-dependent effects. As such, it is critical to understand the influence of technique-induced transition metal dichalcogenide (TMDC) optical properties that impact the design, performance, and integration of advanced optical coatings and devices. Here, we examine the optical properties of semiconducting MoS2 films from the exfoliation formulations of four prominent approaches: solvent-mediated exfoliation, chemical exfoliation with phase reconversion, redox exfoliation, and native redox exfoliation. The resulting MoS2 films exhibit distinct refractive indices (n), extinction coefficients (k), dielectric functions (ε1 and ε2), and absorption coefficients (α). For example, a large index contrast of Δn ≈ 2.3 is observed. These exfoliation procedures and related chemistries produce different exfoliated flake dimensions, chemical impurities, carrier doping, and lattice strain that influence the resulting optical properties. First-principles calculations further confirm the impact of lattice defects and doping characteristics on MoS2 optical properties. Overall, incomplete phase reconfiguration (from 1T to mixed crystalline 2H and amorphous phases), lattice vacancies, intraflake strain, and Mo oxidation largely contribute to the observed differences in the reported MoS2 optical properties. These findings highlight the need for controlled technique-induced effects as well as the opportunity for continued development of, and improvement to, liquid phase exfoliation methodologies. Such chemical and processing-induced effects present compelling routes to engineer exfoliated TMDC optical properties toward the development of next-generation high-performance mirrors, narrow bandpass filters, and wavelength-tailored absorbers.
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- 2023
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3. Thermally Reduced Graphene Oxide Membranes Revealed Selective Adsorption of Gold Ions from Mixed Ionic Solutions
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Yu Qiang, Siyan Gao, Yueyu Zhang, Shuai Wang, Liang Chen, Liuhua Mu, Haiping Fang, Jie Jiang, and Xiaoling Lei
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rGO membranes ,adsorption ,selectivity ,gold recycling ,adsorptive−reduction ,two-dimensional materials ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The recovery of gold from water is an important research area. Recent reports have highlighted the ultrahigh capacity and selective extraction of gold from electronic waste using reduced graphene oxide (rGO). Here, we made a further attempt with the thermal rGO membranes and found that the thermal rGO membranes also had a similarly high adsorption efficiency (1.79 g gold per gram of rGO membranes at 1000 ppm). Furthermore, we paid special attention to the detailed selectivity between Au3+ and other ions by rGO membranes. The maximum adsorption capacity for Au3+ ions was about 16 times that of Cu2+ ions and 10 times that of Fe3+ ions in a mixture solution with equal proportions of Au3+/Cu2+ and Au3+/Fe3+. In a mixed-ion solution containing Au3+:Cu2+:Na+:Fe3+:Mg2+ of printed circuit board (PCB), the mass of Au3+:Cu2+:Na+:Fe3+:Mg2+ in rGO membranes is four orders of magnitude higher than the initial mass ratio. A theoretical analysis indicates that this selectivity may be attributed to the difference in the adsorption energy between the metal ions and the rGO membrane. The results are conducive to the usage of rGO membranes as adsorbents for Au capture from secondary metal resources in the industrial sector.
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- 2023
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4. Fabrication of a Mesoporous Multimetallic Oxide-based Ion-Sensitive Field Effect Transistor for pH Sensing
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Tingke Rao, Jialin Li, Wen Cai, Min Wu, Jie Jiang, Peng Yang, Yuanliang Zhou, and Wugang Liao
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Chemistry ,QD1-999 - Published
- 2021
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5. Multitask CapsNet: An Imbalanced Data Deep Learning Method for Predicting Toxicants
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Yiwei Wang, Binyou Wang, Jie Jiang, Jianmin Guo, Jia Lai, Xiao-Yuan Lian, and Jianming Wu
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Chemistry ,QD1-999 - Published
- 2021
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6. Research on alkali metal-modified Pd catalyst for oxygen removal from propylene
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Jinchong Zhao, Jie Jiang, Song Wen, Jing Zhang, Changsheng Zhang, Nan Sheng, Wei Liang, Bing Sun, Wei Xu, Zhe Yang, and Yuan Pan
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Pd catalyst ,alkali metal modification ,β-PDH ,oxygen removal ,propylene purification ,Chemistry ,QD1-999 - Abstract
Graphical AbstractTo recycle the propylene safely from a gas mixture consisting of propylene and oxygen, alkali metal-modified Pd catalysts were used to remove oxygen from the gas with the help of hydrogen.
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- 2022
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7. Combined dehydrogenation of glycerol with catalytic transfer hydrogenation of H2 acceptors to chemicals: Opportunities and challenges
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Guangyu Zhang, Jian Zhao, Xin Jin, Yanan Qian, Mingchuan Zhou, Xuewu Jia, Feng Sun, Jie Jiang, Wei Xu, and Bing Sun
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glycerol ,lactic acid ,H2 acceptor ,CO2 ,dehydrogenation ,catalytic transfer hydrogenation ,Chemistry ,QD1-999 - Abstract
Catalytic transformation of low-cost glycerol to value-added lactic acid (LA) is considered as one of the most promising technologies for the upgradation of glycerol into renewable products. Currently, research studies reveal that anaerobic transformation of glycerol to LA could also obtain green H2 with the same yield of LA. However, the combined value-added utilization of released H2 with high selectivity of LA during glycerol conversion under mild conditions still remains a grand challenge. In this perspective, for the first time, we conducted a comprehensive and critical discussion on current strategies for combined one-pot/tandem dehydrogenation of glycerol to LA with catalytic transfer hydrogenation of H2 acceptors (such as CO2) to other chemicals. The aim of this overview was to provide a general guidance on the atomic economic reaction pathway for upgrading low-cost glycerol and CO2 to LA as well as other chemicals.
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- 2022
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8. Minute-Scale Synthesis of Nano Silicalite-1 Zeolites
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Changsheng Zhang, Shaoqi Chu, Jie Jiang, Jinchong Zhao, Song Wen, Bing Sun, and Wei Xu
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zeolite ,silicalite-1 ,fast synthesis ,green chemistry ,O2 removal ,Chemistry ,QD1-999 - Abstract
Synthesis of zeolites in more efficient and greener methods is of great significance in both industrial and academic fields. However, the relative long time for zeolite crystallization and much consumption of water solvent make the target challengeable. Herein, a route for ultrafast synthesis of nano Silicalite-1 zeolites in 10 min with much less water consumption has been developed. Comprehensive characterizations, i.e., X-ray powder diffraction, N2 sorption, scanning electron microscope, and NMR, confirm the high quality of such obtained Silicalite-1 zeolites. In the catalytic deoxygenation of O2-containing ethylene (mixture of O2 and ethylene), these reported Silicalite-1 zeolite samples show the comparable performance with the conventional Silicalite-1 zeolites synthesized under hydrothermal conditions. This research therefore provides a new trial toward the ultrafast synthesis of zeolite materials in an environment-friendly route.
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- 2022
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9. Analysis on Bearing Behavior of Single Pile under Combined Action of Vertical Load and Torque in Expansive Soil
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Zhi Wang, Jie Jiang, Shunwei Wang, Chenzhi Fu, and Di Yang
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single pile ,expansive soil ,bearing characteristics ,V→T loading path ,model test ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
To reasonably analyze the bearing characteristics of curved beam bridge pile foundation under the combined action of vertical force (V) and torque (T) in expansive soil, a method of determining Tu (limit torque) under the action of V is proposed. Considering the effects of expansive force and ground heave after immersion, the load transfer function at the pile–soil interface with positive and negative friction resistance is established. The nonlinear solution of a single pile under vertical load is achieved by the finite difference method. Subsequently, the circumferential limit friction resistance is modified, and a loop iteration program is compiled through MATLAB. Thus, the bearing capacity of single pile under the loading path of V→T is obtained. The corresponding failure envelope curve is drawn and verified by laboratory model tests. Based on the verified solution, the bearing capacity envelope curve and deformation characteristics of single pile are analyzed. The influence of the expansion rate on the bearing capacity envelope curve is discussed, and reasonable engineering suggestions are put forward.
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- 2023
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10. The effect of tacrolimus-containing polyethylene glycol-modified maghemite nanospheres on reducing oxidative stress and accelerating the healing spinal cord injury of rats based on increasing M2 macrophages
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Jing Wang, Tuxiu Xie, Xiaobing Long, Rukai Gao, Lulu Kang, Qingyuan Wang, Jie Jiang, Lu Ye, and Jingjun Lyu
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Spinal cord injury ,Tacrolimus ,Maghemite nanosphere ,Oxidative stress ,Macrophages ,Chemistry ,QD1-999 - Abstract
One of the key factors in repairing spinal cord injury is reducing inflammation and oxidative stress. So, it was tried to increase the growth of neurons more rapidly by enhancing the macrophage M2 and reducing the M1 to M2 ratio by using the possible role of tacrolimus (TAC) loaded on polyethylene glycol-modified maghemite nanospheres (PEG-MNs). In this regard, after designing PEG-MNs-TAC in a three-step process and examining their properties through TEM, DLS and XRD analyses. A toxicity assay was then performed by using MTT test. To investigate the healing role of TAC on damaged tissue, a rat model was used to induce injury in vertebral T6 through physical injury. Then, rats were allocated into five groups: negative control, MNs, PEG-MNs , TAC (and PEG-MNs-TAC. Next, motor scale index, behavioral test, macrophage markers expression, concentration of IL-6, IL-2 and TNF-α, and oxidative stress on rats were analyzed. The results revealed that TAC and PEG-MNs-TAC significantly improved mobility and neuropathic tests. Furthermore, the decrease in TNF-α, IL-6, and IL-2 along with the decrease in ROS levels in the injured spinal cord were considerable in both TAC- and PEG-MNs-TAC-treated groups. Nonetheless, the PEG-MNs-TAC exposed more favorable outcomes compared to TAC. Overall, PEG-MNs-TAC could provide a new treatment for damaged spinal cord care by reducing oxidative stress and decreasing M1 to M2 ratio.
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- 2022
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11. A Review of Noble Metal Catalysts for Catalytic Removal of VOCs
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Shaoqi Chu, Enlai Wang, Fushan Feng, Changsheng Zhang, Jie Jiang, Qinqin Zhang, Fang Wang, Liancheng Bing, Guangjian Wang, and Dezhi Han
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volatile organic compounds ,catalytic oxidation ,noble metal catalyst ,reaction mechanism ,support ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Volatile organic compounds (VOCs) are important precursors for the formation of secondary pollutants, such as fine particulate matter (PM) and ozone (O3), which will lead to severe atmospheric environmental problems to restrict the sustainable development of the social economy. Catalytic oxidation is a safe, eco-friendly, and simple method for eliminating VOCs, which can be converted into CO2 and H2O without the generation of other harmful substances. The fabrication and development of catalysts are very crucial to enhance the catalytic oxidation efficiency of the removal of VOCs. The noble metal catalyst is one of the commonly used catalysts for the catalytic oxidation of VOCs because of the high reaction activity, good stability, poisoning-resistant ability, and easy regeneration. In this review, the research progress of noble metal (Pt, Pd, Au, Ag, and Ir) catalysts for the removal of VOCs in recent years was summarized with the discussion of the influence factors in the preparation process on the catalytic performance. The reaction mechanisms of the removal of VOCs over the corresponding noble metal catalysts were also briefly discussed.
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- 2022
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12. Risk Coupling Analysis of Deep Foundation Pits Adjacent to Existing Underpass Tunnels Based on Dynamic Bayesian Network and N–K Model
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Jie Jiang, Guangyang Liu, and Xiaoduo Ou
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dynamic risk assessment ,adjacent existing underpass tunnel ,deep foundation pit ,dynamic Bayesian network (DBN) ,association rule mining (ARM) ,N–K model ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Because deep foundation pits and tunnels are deformation-sensitive structures, the safety of these projects is generally affected by coupled risks. In deep foundation pit construction, if the existing tunnel structure adjacent to the deposit is damaged, it can produce a severe group disaster. It is necessary to identify an efficient risk analysis model to study the dynamic coupled risk of deep foundation pit projects adjacent to existing underpass tunnels and to analyze the risk evolution law to achieve effective real-time safety control. This study proposes a coupled risk analysis model using the N–K model and dynamic Bayesian network to construct deep foundation pits in adjacent existing underpass tunnels. The model is predicated on association rules to explore the interrelationship between risk factors to build a dynamic Bayesian network structure. In addition, the N–K model is utilized to quantify coupled risks under such complex working conditions and to optimize the dynamic Bayesian network structure. The developed model clarifies the risk coupling mechanism of deep foundation pit construction adjacent to an existing underpass tunnel, finds the critical points in the risk transfer process, and conducts dynamic risk prediction and accident causation diagnosis for the coupled risk to realize the dynamic control of the coupled risk in the adjacent existing underpass tunnel construction. Taking the Nanning underground comprehensive utilization project as an example, the validity and applicability of the proposed approach were tested. The results showed that the model is feasible and has application potential, providing effective decision support for safety control while constructing deep foundation pits adjacent to existing tunnels.
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- 2022
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13. Acidovorax citrulli Effector AopV Suppresses Plant Immunity and Interacts with Aromatic Dehydratase ADT6 in Watermelon
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Jie Jiang, Mei Zhao, Xiaoxiao Zhang, Linlin Yang, Nuoya Fei, Weiqin Ji, Wei Guan, Ron Walcott, Yuwen Yang, and Tingchang Zhao
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Acidovorax citrulli ,bacterial fruit blotch ,effectors ,AopV ,ADT6 ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Bacterial fruit blotch (BFB) is a disease of cucurbit plants caused by Acidovorax citrulli. Although A. citrulli has great destructive potential, the molecular mechanisms of pathogenicity of A. citrulli are not clear, particularly with regard to its type III secreted effectors. In this study, we characterized the type III secreted effector protein, AopV, from A. citrulli strain Aac5. We show that AopV significantly inhibits reactive oxygen species and the expression of PTI marker genes, and helps the growth of Pseudomonas syringae D36E in Nicotiana benthamiana. In addition, we found that the aromatic dehydratase ADT6 from watermelon was a target of AopV. AopV interacts with ADT6 in vivo and in vitro. Subcellular localization indicated ADT6 and AopV were co-located at the cell membrane. Together, our results reveal that AopV suppresses plant immunity and targets ADT6 in the cell membrane. These findings provide an new characterization of the molecular interaction of A. citrulli effector protein AopV with host cells.
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- 2022
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14. Research on the Analytical Conversion Method of Q-s Curves for Self-Balanced Test Piles in Layered Soils
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Xiaoduo Ou, Guangyuan Chen, Lu Bai, Jie Jiang, Yuchu Zeng, and Hailiang Chen
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self-balanced test pile ,model test ,analytical conversion method ,ultimate bearing capacity ,engineering application ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
An analytical conversion method was developed for the self-balanced test results of monopile bearing capacity in layered soils to realize the better applicability of the self-balanced test theory for the bearing capacity test of foundation piles. To the additional settlement of the lower pile bottom brought on by the negative friction of the upper pile soil during the loading process in layered soils, the interaction effect between the upper piles and lower piles is first taken into account. To accurately convert the results of the self-balanced test pile into the traditional static load test curve form and solve the ultimate bearing capacity, the displacements and internal forces at micro-segment piles in each layer of soil were obtained using the finite difference method. Then, for verification, conventional static test piles and indoor model tests were conducted in a multi-layered ground foundation. The outcome demonstrates that the simplified conversion method’s bearing capacity of the test pile is greater than that of the traditional static pressure test, the analytical conversion method’s Q-s curve is relatively similar to the results of the conventional static load test, and the accuracy of the analytical conversion results is increased by about 9.3 percent. At the same time, the analytical conversion method was applied to the self-balanced test project of bored cast-in-place piles in Wutong Garden, Laibin, Guangxi, China, and the accurate bearing capacity and internal force deformation characteristics were obtained. The accuracy of the calculation result is improved by 12% compared with that of the simple conversion calculation result. Therefore, it can be widely promoted and applied in self-balanced pile bearing capacity test projects.
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- 2022
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15. Error Correction Method of TIADC System Based on Parameter Estimation of Identification Model
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Ning Sun, Jie Li, Debiao Zhang, Chenjun Hu, Xiaofei Peng, Jie Jiang, Shuai Wang, Zeyu Zhang, and Wentao Cui
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data acquisition system ,time-interleaved ADC ,channel mismatch error ,system identification ,frequency characteristics ,parameter estimation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The performance of analog-to-digital converters (ADCs) has reached a bottleneck due to the limitations of the manufacturing process and testing environment. Time-interleaved ADC (TIADC) technology can increase the sampling rate without changing the resolution. However, channel mismatch severely degrades the dynamic performance of the TIADC system. For the channel mismatch problem of TIADC, most of the current solutions have preconditions, such as eliminating only some kind of error or increasing the complexity of the hardware. A few methods can estimate multiple errors without changing the hardware circuit. To improve the dynamic performance of the TIADC system, on the basis of an in-depth study of the channel mismatch error of TIADC, according to the system identification theory, an identification model is designed to characterize the frequency characteristics of TIADC. Using the system observation data, the transfer function parameters of the system are recursively estimated. By constructing and verifying the identification model of the TIADC system, and then through the frequency domain correction method, a digital compensation filter is established to complete the error correction of the system. The test results of the four-channel TIADC high-speed data acquisition system show that the actual input and output characteristics of the test system are consistent with the nature of the identification model. The four channels of the TIADC system are provided by four sub-channels of two AD9653 chips, and the highest sampling rate of a single channel is 125MSPS. For sinusoidal input signals from 20 MHz to 150 MHz, the sampling system can achieve a signal-to-noise ratio (SNR) above 56.8 dB and spurious free dynamic range (SFDR) above 69.7 dB. The dynamic performance of the sampling system is nearly equivalent to that of its sub-ADC; the feasibility of the model identification method and the effectiveness of error correction are verified in simulation and experiment.
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- 2022
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16. Assessing Redox Properties of Natural Organic Matters with regard to Electron Exchange Capacity and Redox-Active Functional Groups
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Zhiyuan Xu, Zhen Yang, Hongping Wang, and Jie Jiang
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Chemistry ,QD1-999 - Abstract
Redox processes in groundwater play an important role in bioavailability, toxicity, and mobility of redox-active elements and contaminants. A recent study has demonstrated that low-molecular-weight fraction (LMWF) of humic substances with great number of redox-active functional groups (RAFGs) exhibits great reducing capacity. However, whether LMWF of natural organic matter (NOM) exhibits high redox capacity still remains unclear. Therefore, this study extracted Pahokee peat NOM (PPNOM) and Leonardite NOM (LNOM) from soils, and then LMWFs in these NOMs were collected using a dialysis method. Electron exchange capacities (EEC) and RAFGs of LMWF NOMs at different Eh were analyzed using a novel electrochemical method and a three-dimensional excitation emission fluorescence (3DEEM) spectroscopy. We found that the reducing capacity in LMWF PPNOM was approximately 5-6 times higher than the bulk NOM, while only 7.8% LMWF PPNOM was accounted for in the bulk NOM. An increasing in EEC (EAC + EDC, where EAC is the electron accepting capacity and EDC is the electron donating capacity) of LMWF PPNOM and LNOM with Eh reduced from −0.49 V to −0.69 V. Additionally, an obvious increase in fluorescent intensities of quinone-like fluorophores before and after being reduced LMWF LNOM is responsible for high EAC of LMWF LNOM. These findings provide a better understanding of relationship between RAFGs Eh in LMWF of NOM, further helping in predicting and protection of groundwater environment and fate of transformation and transport for redox-active contaminants in groundwater.
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- 2020
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17. Adjuvant Immune Enhancement of Subunit Vaccine Encoding pSCPI of Streptococcus iniae in Channel Catfish (Ictalurus punctatus)
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Jie Jiang, Zonglin Zheng, Kaiyu Wang, Jun Wang, Yang He, Erlong Wang, Defang Chen, Ping Ouyang, Yi Geng, and Xiaoli Huang
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Channel catfish ,Streptococcus iniae ,subunit vaccine ,pSCPI ,adjuvant ,immune effect ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Channel catfish (Ictalurus punctatus) is an important agricultural fish that has been plagued by Streptococcus iniae (S. iniae) infections in recent years, some of them severe. C5a peptidase is an important virulent factor of S. iniae. In this study, the subunit vaccine containing the truncated part of C5a peptidase (pSCPI) was mixed with aluminum hydroxide gel (AH), propolis adjuvant (PA), and Freund’s Incomplete Adjuvant (FIA). The immunogenicity of the pSCPI was detected by Western-blot in vitro. The relative percent survival (RPS), lysozyme activity, antibody titers, and the expression of the related immune genes were monitored in vivo to evaluate the immune effects of the three different adjuvants. The results showed that pSCPI exerted moderate immune protection (RPS = 46.43%), whereas each of the three adjuvants improved the immune protection of pSCPI. The immunoprotection of pSCPI + AH, pSCPI + PA, and pSCPI + FIA was characterized by RPS values of 67.86%, 75.00% and, 85.71%, respectively. Further, each of the three different adjuvanted pSCPIs stimulated higher levels of lysozyme activity and antibody titers than the unadjuvanted pSCPI and/or PBS buffer. In addition, pSCPI + FIA and pSCPI + PA induced expression of the related immune genes under investigation, which was substantially higher than the levels stimulated by PBS. pSCPI + AH significantly stimulated the induction of MHC II β, CD4-L2, and IFN-γ, while it induced slightly higher production of TNF-α and even led to a decrease in the levels of IL-1β, MHC I α, and CD8 α. Therefore, we conclude that compared with the other two adjuvants, FIA combined with pSCPI is a more promising candidate adjuvant against S. iniae in channel catfish.
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- 2015
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18. Identification and Functional Analysis of AopN, an Acidovorax Citrulli Effector that Induces Programmed Cell Death in Plants
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Xiaoxiao Zhang, Mei Zhao, Jie Jiang, Linlin Yang, Yuwen Yang, Shanshan Yang, Ron Walcott, Dewen Qiu, and Tingchang Zhao
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AopN ,programmed cell death ,Acidovorax citrulli ,plant pathogen ,effector-triggered immunity ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Bacterial fruit blotch (BFB), caused by Acidovorax citrulli, seriously affects watermelon and other cucurbit crops, resulting in significant economic losses. However, the pathogenicity mechanism of A. citrulli is not well understood. Plant pathogenic bacteria often suppress the plant immune response by secreting effector proteins. Thus, identifying A. citrulli effector proteins and determining their functions may improve our understanding of the underlying pathogenetic mechanisms. In this study, a novel effector, AopN, which is localized on the cell membrane of Nicotiana benthamiana, was identified. The functional analysis revealed that AopN significantly inhibited the flg22-induced reactive oxygen species burst. AopN induced a programmed cell death (PCD) response. Unlike its homologous protein, the ability of AopN to induce PCD was dependent on two motifs of unknown functions (including DUP4129 and Cpta_toxin), but was not dependent on LXXLL domain. More importantly, the virulence of the aopN mutant of A. citrulli in N. benthamiana significantly decreased, indicating that it was a core effector. Further analysis revealed that AopN interacted with watermelon ClHIPP and ClLTP, which responds to A. citrulli strain Aac5 infection at the transcription level. Collectively, these findings indicate that AopN suppresses plant immunity and activates the effector-triggered immunity pathway.
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- 2020
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19. High-Sensitivity Terahertz Refractive Index Sensor in a Multilayered Structure with Graphene
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Jiao Tang, Yunyang Ye, Jiao Xu, Zhiwei Zheng, Xiangliang Jin, Leyong Jiang, Jie Jiang, and Yuanjiang Xiang
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optical resonance ,terahertz sensor ,graphene ,Chemistry ,QD1-999 - Abstract
In this paper, we propose a high-sensitivity optical sensor at terahertz frequencies based on a composite structure containing a one-dimensional photonic crystal (1D PC) coated with a layer of monolayer graphene. Between the 1D PC and the graphene there is a sensing medium. This high-sensitivity phenomenon originates from the excitation of optical resonance between the graphene and the 1D PC. The proposed sensor is highly sensitive to the Fermi energy of graphene, the thickness and refractive index of the sensing medium, and the number of graphene layers. By selecting appropriate parameters, the maximum sensitivity ( 407.36 ∘ / RIU ) is obtained. We believe the proposed configuration is promising for fabricating graphene-based biosensor- or gas-sensor devices and other related applications in the terahertz band.
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- 2020
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20. CFAM: Estimating 3D Hand Poses from a Single RGB Image with Attention
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Xianghan Wang, Jie Jiang, Yanming Guo, Lai Kang, Yingmei Wei, and Dan Li
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hand pose estimation ,cfam ,3d keypoint ,rgb image ,attention ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Precise 3D hand pose estimation can be used to improve the performance of human−computer interaction (HCI). Specifically, computer-vision-based hand pose estimation can make this process more natural. Most traditional computer-vision-based hand pose estimation methods use depth images as the input, which requires complicated and expensive acquisition equipment. Estimation through a single RGB image is more convenient and less expensive. Previous methods based on RGB images utilize only 2D keypoint score maps to recover 3D hand poses but ignore the hand texture features and the underlying spatial information in the RGB image, which leads to a relatively low accuracy. To address this issue, we propose a channel fusion attention mechanism that combines 2D keypoint features and RGB image features at the channel level. In particular, the proposed method replans weights by using cascading RGB images and 2D keypoint features, which enables rational planning and the utilization of various features. Moreover, our method improves the fusion performance of different types of feature maps. Multiple contrast experiments on public datasets demonstrate that the accuracy of our proposed method is comparable to the state-of-the-art accuracy.
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- 2020
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21. Object Detection Algorithm Based on Multiheaded Attention
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Jie Jiang, Hui Xu, Shichang Zhang, and Yujie Fang
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object detection ,attention mechanism ,multiheaded attention ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study proposes a multiheaded object detection algorithm referred to as MANet. The main purpose of the study is to integrate feature layers of different scales based on the attention mechanism and to enhance contextual connections. To achieve this, we first replaced the feed-forward base network of the single-shot detector with the ResNet−101 (inspired by the Deconvolutional Single-Shot Detector) and then applied linear interpolation and the attention mechanism. The information of the feature layers at different scales was fused to improve the accuracy of target detection. The primary contributions of this study are the propositions of (a) a fusion attention mechanism, and (b) a multiheaded attention fusion method. Our final MANet detector model effectively unifies the feature information among the feature layers at different scales, thus enabling it to detect objects with different sizes and with higher precision. We used the 512 × 512 input MANet (the backbone is ResNet−101) to obtain a mean accuracy of 82.7% based on the PASCAL visual object class 2007 test. These results demonstrated that our proposed method yielded better accuracy than those provided by the conventional Single-shot detector (SSD) and other advanced detectors.
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- 2019
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22. Prominent Conductor Mechanism-Induced Electron Transfer of Biochar Produced by Pyrolysis of Nickel-Enriched Biomass
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Wenbing Tan, Renfei Li, Hanxia Yu, Xinyu Zhao, Qiuling Dang, Jie Jiang, Lei Wang, and Beidou Xi
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biochar ,Ni-rich biomass ,microbial reduction ,electron transfer ,conductor mechanism ,redox mechanism ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Biochar is redox-active and can function as a sustainable electron shuttle in catalyzing relevant redox reactions. It plays a crucial role in environmental remediation. In this work, we used different-nickel (Ni)-level biochars produced by the pyrolysis of plant biomass with correspondingly different Ni levels as extracellular electron shuttles for microbial reduction of ferrihydrite by Shewanella oneidensis MR-1. A high Ni level of the precursor considerably enhanced the conductor mechanism of the produced biochar and thus enabled the biochar to catalyze increased microbial reductions of the Fe(III) mineral, but it did not promote the charging and discharging capacities of the produced biochar. This study can aid in the search for natural biomass with high Ni content to establish low-cost biochars with wide-ranging applications in catalyzing the redox-mediated reactions of pollutants.
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- 2018
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23. Influence of Illumination Polarization and Target Structure on Measurement Sensitivity of Through-Focus Scanning Optical Microscopy
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Yufu Qu, Renju Peng, Jialin Hao, Hui Pan, Jiebin Niu, and Jie Jiang
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through-focus optical microscopy ,illumination polarization ,target structure ,sensitivity ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Unlike the optical information taken from a single in-focus image of general optical microscopy, through-focus scanning optical microscopy (TSOM) involves scanning a target through the focus and capturing of a series of images. These images can be used to conduct three-dimensional inspection and metrology with nanometer-scale lateral and vertical sensitivity. The sensitivity of TSOM strongly depends on many mechanical and optical factors. In this study, how illumination polarization and target structure affect the sensitivity of TSOM is analyzed. Firstly, the complete imaging procedure of the polarized light is investigated. Secondly, through-focus scanning results of different targets with two illumination polarizations are simulated using the finite-difference time-domain method. Thirdly, a few experiments are performed to verify the influence of illumination polarization and target structures on the sensitivity of TSOM. Both the results of the simulation and experiments illustrate an apparent influence of polarization on the sensitivity of inspecting the targets with center asymmetric structures. For enhanced sensitivity, illumination polarization should be perpendicular to the target texture. This conclusion is meaningful to adjust illumination polarization purposefully for different structure characteristics and improve the sensitivity of metrology.
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- 2018
- Full Text
- View/download PDF
24. A Model of Interaction between Nicotinamide Adenine Dinucleotide Phosphate (NADPH) Oxidase and Apocynin Analogues by Docking Method
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Jie Jiang, Hongjun Kang, Xiaoliang Song, Sichao Huang, Sha Li, and Jun Xu
- Subjects
NADPH oxidase ,apocynin analogues ,inhibitor ,docking ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Some apocynin analogues have exhibited outstanding inhibition to NADPH oxidase. In this study, the key interactions between apocynin analogues and NADPH oxidase were analyzed by the docking method. The potential active site was first identified by the SiteID program combining with the key residue CYS378. Afterwards, the compounds in the training set were docked into NADPH oxidase (1K4U) under specific docking constraints to discuss the key interactions between ligands and the receptor. These key interactions were then validated by the consistence between the docking result and the experimental result of the test set. The result reveals that the Pi interaction between apocynin analogues and NADPH oxidase has a direct contribution to inhibition activities, except for H-bond formation and docking score. The key interactions might be valuable to discover and screen apocynin analogues as potent inhibitors of NADPH oxidase.
- Published
- 2013
- Full Text
- View/download PDF
25. RNAi-mediated suppression of the abscisic acid catabolism gene OsABA8ox1 increases abscisic acid content and tolerance to saline–alkaline stress in rice (Oryza sativa L.)
- Author
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Xiaolong Liu, Chang-Jie Jiang, Wei Lixing, Guo-Hui Zhang, Yang-Yang Jin, Li Xiaowei, Xianzhi Xie, Chongke Zheng, and Zhengwei Liang
- Subjects
Oryza sativa ,biology ,Crop yield ,fungi ,food and beverages ,Plant Science ,biology.organism_classification ,Japonica ,Salinity ,chemistry.chemical_compound ,Horticulture ,chemistry ,Seedling ,Cultivar ,Agronomy and Crop Science ,Abscisic acid ,Panicle - Abstract
Saline–alkaline (SA) stress is characterized by high salinity and high alkalinity (high pH), which severely inhibit plant growth and cause huge losses in crop yields worldwide. Here we show that a moderate elevation of endogenous abscisic acid (ABA) levels by RNAi-mediated suppression of OsABA8ox1 (OsABA8ox1-kd), a key ABA catabolic gene, significantly increased tolerance to SA stress in rice plants. We produced OsABA8ox1-kd lines in two different japonica cultivars, Dongdao 4 and Nipponbare. Compared with non-transgenic control plants (WT), the OsABA8ox1-kd seedlings accumulated 25.9%–55.7% higher levels of endogenous ABA and exhibited reduced plasmalemma injury, ROS accumulation and Na+/K+ ratio, and higher survival rates, under hydroponic alkaline conditions simulated by 10, 15, and 20 mmol L−1 of Na2CO3. In pot trials using SA field soils of different alkali levels (pH 7.59, 8.86, and 9.29), OsABA8ox1–kd plants showed markedly higher seedling survival rates and more vigorous plant growth, resulting in significantly higher yield components including panicle number (85.7%–128.6%), spikelets per panicle (36.9%–61.9%), branches (153.9%–236.7%), 1000–kernel weight (20.0%–28.6%), and percentage of filled spikelets (96.6%–1340.8%) at harvest time. Under severe SA soil conditions (pH = 9.29, EC = 834.4 μS cm−1), OsABA8ox1-kd lines showed an 194.5%–1090.8% increase in grain yield per plant relative to WT plants. These results suggest that suppression of OsABA8ox1 to increase endogenous ABA levels provides a new molecular approach for improving rice yield in SA paddies.
- Published
- 2022
26. Effect of heat treatment temperature on the microstructure and wear corrosion properties of NiCrBSi–TiN composite coatings
- Author
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Yong Yang, Jining He, Yanchun Dong, YuXin Wang, Linlin Zhu, YunLong Chi, Jie Jiang, and Xingye Mao
- Subjects
Materials science ,Scanning electron microscope ,Process Chemistry and Technology ,Composite number ,Energy-dispersive X-ray spectroscopy ,chemistry.chemical_element ,Microstructure ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Corrosion ,chemistry ,Transmission electron microscopy ,Materials Chemistry ,Ceramics and Composites ,Composite material ,Tin ,Tribometer - Abstract
For this study, NiCrBSi–TiN composite coatings were fabricated on Q235 steel substrates by reactive plasma spraying and the coatings were heat treated at 600 °C, 700 °C, 750 °C and 800 °C for 1 hour. The microstructure evolution of these coatings untreated and treated at different temperatures was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The hardness of the coatings was characterised using the Weibull distribution while the wear and corrosion resistance were studied using a block-ring tribometer and an electrochemical workstation. The phase composition of coatings after heat treatment changed, the compactness of coatings was increased, and the interlayer bonding was significantly improved. Comprehensive experimental results illustrated that the performance of the NiCrBSi–TiN composite coatings was excellent at the heat treatment temperature of 700 °C.
- Published
- 2022
27. Understanding the role of nitrogen and sulfur doping in promoting kinetics of oxygen reduction reaction and sodium ion battery performance of hollow spherical graphene
- Author
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Zhong-Jie Jiang, Dayong Zhou, Weiheng Chen, Ru Qiao, K. Raleva, Snežana Papović, Zhongqing Jiang, and Xiaoping Chen
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Materials science ,Graphene ,Doping ,Kinetics ,Substrate (chemistry) ,chemistry.chemical_element ,Sodium-ion battery ,General Chemistry ,Catalysis ,Anode ,law.invention ,chemistry ,Chemical engineering ,law ,General Materials Science ,Carbon - Abstract
Here, a simple, economical one-step doping strategy is adopted to prepare N, S co-doped graphene hollow spheres (NSGHS). The NSGHS exhibits remarkable oxygen-reduction-reaction (ORR) activity with a high half-wave potential (E1/2) of 0.847 V vs. RHE and considerable long-term stability. When applied as anode materials for sodium-ion batteries (SIBs), it could deliver a high reversible capacity of 385 mAh g−1 at 500 mA g−1, excellent rate performance of 308 mAh g−1 at even 20 A g−1 and superior cycling performance at 10 A g−1 during 5000 cycles with negligible capacity fade. DFT calculation reveals that the doping of N and S endows the surrounding carbon with high positive charge and spin density, respectively, making them be highly active ORR catalytic sites except for S itself. Despite the possible oxidization of C–S–C active sites, the rest C atoms of NSGHS will still hold a considerably high catalytic activity superior to those of mono-doped or undoped cases. In addition, S doping will improve the binding between Na and graphene substrate to get a high capacity and N doping effectively curbs the rising of oxygen levels and oxidization of S in C–S–C active sites, thus the excellent stability for ORR and SIBs. © 2021 Elsevier Ltd
- Published
- 2022
28. Emerging investigator series: long-term exposure of amorphous silica nanoparticles disrupts the lysosomal and cholesterol homeostasis in macrophages
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Jun Jiang, Ruibin Li, Nikolai Tarasenko, Yanxia Pan, Xiaoming Cai, Xi Liu, Fangjun Wang, Shujuan Xu, Qianqian Xie, Ronglin Ma, Weili Wang, Ye Zhou, Jie Jiang, Di Wu, and Huizhen Zheng
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Chemistry ,Cholesterol ,Materials Science (miscellaneous) ,Autophagy ,Lipid metabolism ,Environmental exposure ,Proteomics ,Acute toxicity ,Cell biology ,chemistry.chemical_compound ,lipids (amino acids, peptides, and proteins) ,Cytotoxicity ,Flux (metabolism) ,General Environmental Science - Abstract
Amorphous silica nanoparticles (ASiNPs) are generally considered to be biocompatible with limited acute toxicity. These nanoparticles were therefore exploited in diverse nanoproducts (e.g. foods and cosmetics) and may be released into environments in daily life. This has led to substantial concerns on their affects by long-term exposure. Herein, Raw264.7 cells were subjected to long-term exposure of ASiNPs for assessment of the potential cytotoxicity. Two ASiNPs with diameters of 50 ~ 100 nm (ASiNP1) and 450 ~ 500 nm (ASiNP2) were synthesized and comprehensively characterized. The acquired cells were denoted as Raw264.7-NP1 (ASiNP1 treatment) and Raw264.7-NP2 (ASiNP2 treatment) after long-term exposure. Both the small and large ASiNPs showed similar cellular distributions in lysosomes. We therefore examined the impacts of ASiNPs in lysosomal density, size and function by microscopy imaging and proteomics analysis. As a result, Raw264.7-NP1 cells displayed 2.3-fold higher lysosomal density and 149% increments of average lysosomal area than parent cells. Proteomics analysis of lysosomes revealed 25 significantly changed proteins closely relating to 5 cellular effects, including autophagy and lipid metabolism. Confocal imaging and immunoblotting of LC-3 proteins indicated an accumulation of autophagosomes in Raw264.7-NP1 cells. Elevation of cholesterol was also demonstrated in Raw264.7-NP1 cells by visualization and quantification of cellular cholesterols. Notably, the cholesterol elevation in Raw264.7-NP1 cells could be ameliorated by acceleration of autophagic flux (rapamycin treatment) but aggregated by blockage of autolysosome formation (chloroquine treatment), indicating the critical role of autophagic flux in lipid metabolism. Overall, the discovery of these hazard effects raised warnings for the long-term uses of ASiNP-based nanoproducts and may facilitate the decision making on environmental exposure thresholds of ASiNPs.
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- 2022
29. Thin interfacial film spontaneously produces hydrogen peroxide: mechanism and application for perfluorooctanoic acid degradation
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Wenxin Wang, Hong Zhang, Jing He, Junyu Liu, Kai Yu, Yuwei He, Qianhui Liu, Jie Jiang, and Lina Qiao
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Chemistry ,Radical ,chemistry.chemical_element ,Substrate (chemistry) ,General Chemistry ,Oxygen ,Decomposition ,Catalysis ,chemistry.chemical_compound ,Chemical engineering ,Materials Chemistry ,Degradation (geology) ,Thin film ,Hydrogen peroxide - Abstract
An effective decontamination method for soils remediation is a long-standing challenge. Herein, hydrogen peroxide (H2O2) was spontaneously produced in thin films generated by evaporating almost all the water. H2O2-sensitive test strips and oxidation of 2-hydroxybenzophenone to 2-hydroxyphenyl benzoate confirmed the generation of H2O2. Experiments in which reaction time and temperature were varied and established dependence of H2O2 production on the long-lasting thin films. H2O2 production was independence of irradiation and oxygen from air or dissolved oxygen. Spin-trapping probe experiments suggested that electric fields at the thin interfacial films enabled OH- to hydroxyl radicals and further recombination to H2O2. As a proof-of-principle experiment, perfluorooctanoic acid (PFOA) was effectively degraded on the thin films without catalysts and UV irradiation could further facilitate the degradation. A degradation mechanism was proposed involving the PFOA radicals on thin interfacial films and the subsequent decomposition of the radicals with successive loss of CF2. These findings have important implications for the development of decontamination method for soils remediation based on thin films, because thin film formats are ubiquitous at the surface of soils and when aerosols falling onto a substrate.
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- 2022
30. Development of Highly Potent and Selective Pyrazolopyridine Inhibitor of CDK8/19
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Jie Jiang, John M. Hatcher, Eric S. Wang, Nathanael S. Gray, and Prasanna S Vatsan
- Subjects
Mediator ,Biochemistry ,Chemistry ,Kinase ,Organic Chemistry ,Drug Discovery ,Pyrazolopyridine ,Gene expression ,Cyclin-dependent kinase 8 ,Metabolism ,Negative regulator ,Cortistatin (neuropeptide) - Abstract
[Image: see text] CDK8 and its paralog CDK19 are cyclin-dependent kinases that are core components of the so-called Mediator complex that has essential roles as a positive and negative regulator of gene expression. Several efforts to develop inhibitors have yielded natural and synthetic ATP-competitive compounds including cortistatin A, Sel120, BCD-115, CCT251921 (1), and MSC2530818 (2). Here, we used a hybridization approach starting from CCT251921 and MSC2530818 to derive new inhibitors with the aim of developing highly potent and selective inhibitors of CDK8/19. Initial compounds suffered from rapid aldehyde oxidase-mediated metabolism. This liability was overcome by utilizing a pyrazolopyridine hinge binder with a chlorine at the C-3 position. These efforts resulted in JH-XVI-178 (compound 15), a highly potent and selective inhibitor of CDK8/19 that displays low clearance and moderate oral pharmacokinetic properties.
- Published
- 2021
31. Atroposelective sp 3 C—H Coupling for Kinetic Resolution of Thioanilide Atropisomers
- Author
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Rui-Long Geng, Jia-Hui Wei, Liu-Zhu Gong, and Hua-Jie Jiang
- Subjects
Coupling (electronics) ,Atropisomer ,Phosphoramidite ,Computational chemistry ,Chemistry ,General Chemistry ,Kinetic resolution - Published
- 2021
32. Multitask CapsNet: An Imbalanced Data Deep Learning Method for Predicting Toxicants
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Jia Lai, Xiao-Yuan Lian, Jianming Wu, Binyou Wang, Yiwei Wang, Jianmin Guo, and Jie Jiang
- Subjects
Artificial neural network ,Computer science ,business.industry ,General Chemical Engineering ,Deep learning ,Training data sets ,Failure rate ,General Chemistry ,Machine learning ,computer.software_genre ,Imbalanced data ,Article ,Chemistry ,Artificial intelligence ,business ,QD1-999 ,Sparse data sets ,computer - Abstract
Drug development has a high failure rate, with safety properties constituting a considerable challenge. To reduce risk, in silico tools, including various machine learning methods, have been applied for toxicity prediction. However, these approaches often confront a serious problem: the training data sets are usually biased (imbalanced positive and negative samples), which would result in model training difficulty and unsatisfactory prediction accuracy. Multitask networks obtained significantly better predictive accuracies than single-task methods, and capsule neural networks showed excellent performance in sparse data sets in previous studies. In this study, we developed a new multitask framework based on a capsule neural network (multitask CapsNet) to measure 12 different toxic effects simultaneously. We found that multitask CapsNet excelled in toxicity prediction and outperformed many other computational approaches using the multitask strategy. Only after training on biased data sets did multitask CapsNet achieve significantly improved prediction accuracy on the Tox21 Data Challenge, which gave the largest ratio of highest accuracy (8/12) among compared models. Our model gave a prediction accuracy of 96.6% for the target NR.PPAR.gamma, whose ratio of negative to positive samples was up to 36:1. These results suggested that multitask CapsNet could overcome the bias problems and would provide a novel, accurate, and efficient approach for predicting the toxicities of compounds.
- Published
- 2021
33. Astragalin flavonoid inhibits proliferation in human lung carcinoma cells mediated via induction of caspase-dependent intrinsic pathway, ROS production, cell migration and invasion inhibition and targeting JAK/STAT signalling pathway
- Author
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Xiaowu Shi, Rujuan Wang, Biqing Yu, Guoxing Xu, Jie Jiang, and Fangjing Wen
- Subjects
Lung Neoplasms ,Blotting, Western ,Apoptosis ,chemistry.chemical_compound ,Cell Movement ,Carcinoma, Non-Small-Cell Lung ,Humans ,Neoplasm Invasiveness ,MTT assay ,Viability assay ,Kaempferols ,STAT3 ,Lung ,Cells, Cultured ,Cell Proliferation ,Janus Kinases ,Flavonoids ,A549 cell ,Molecular Structure ,biology ,Chemistry ,JAK-STAT signaling pathway ,General Medicine ,XIAP ,STAT Transcription Factors ,A549 Cells ,Caspases ,Cancer research ,biology.protein ,Comet Assay ,Astragalin ,Reactive Oxygen Species ,DNA Damage ,Signal Transduction - Abstract
The aim of the current study was to investigate the anti-lung cancer effects of astragalin. Studies were also undertaken to evaluate its effects on apoptosis induction, ROS production, cellular migration and invasion and JAK/STAT3 signalling pathway. MTT assay was used to evaluate cell viability in NSCLC A549 cells after exposure to astragalin molecule. Apoptosis was investigated using AO/EB staining, comet assay and western blotting assay. Fluorescence microscopy was implemented to estimate ROS production. Cell migration and invasion were measured using transwell chambers assay. Effects of astragalin on JAK/STAT pathway were investigated using western blotting assay. Results showed astragalin molecule induced inhibition of proliferation in A549 cells in a dose-dependent fashion. Further, the antiproliferative effects were found to mediate via apoptosis as suggested by AO/EB staining and western blotting assay. Astragalin modulated the expressions of caspase-3, caspase-9, Bax, Bak, Cyt-c Bcl-2, XIAP and Bcl-xL. Astragalin induced DNA damage in A549 cells which too indicated apoptotic cell death. Astragalin molecule enhanced the production of ROS by A549 cells. It inhibited both cell migration and invasion of A549 cells in a concentration-dependent manner. Finally, astragalin drug was observed with remarkable potential of targeting JAK/STAT pathway in A549 NSCLC cells. These results indicated that astragalin drug could prove helpful in lung cancer treatment and research provided more in-vivo studies are performed.
- Published
- 2021
34. Functional Characteristics of the Lepidopteran Ionotropic GABA Receptor 8916 Subunit Interacting with the LCCH3 or the RDL Subunit
- Author
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Cheng Wang Sheng, Andrew K. Jones, Chun Qing Zhao, Tao Tang, Zhaojun Han, Jie Jiang, and Qiu Tang Huang
- Subjects
Insecticides ,Chemistry ,Protein subunit ,General Chemistry ,Moths ,Receptors, GABA-A ,Inhibitory postsynaptic potential ,Cell biology ,chemistry.chemical_compound ,Receptors, GABA ,GABA receptor ,Animals ,GABAergic ,Homomeric ,Amino Acid Sequence ,General Agricultural and Biological Sciences ,gamma-Aminobutyric Acid ,Ion channel ,Fipronil ,Ionotropic effect - Abstract
The ionotropic γ-aminobutyric acid (iGABA) receptor is commonly considered as a fast inhibitory channel and is an important insecticide target. Since 1990, RDL, LCCH3, and GRD have been successively isolated and found to be potential subunits of the insect iGABA receptor. More recently, one orphan gene named 8916 was found and considered to be another potential iGABA receptor subunit according to its amino acid sequence. However, little information about 8916 has been reported. Here, the 8916 subunit from Chilo suppressalis was studied to determine whether it can form part of a functional iGABA receptor by co-expressing this subunit with CsRDL1 or CsLCCH3 in the Xenopus oocyte system. Cs8916 or CsLCCH3 did not form functional ion channels when expressed alone. However, Cs8916 was able to form heteromeric ion channels when expressed with either CsLCCH3 or CsRDL1. The recombinant heteromeric Cs8916/LCCH3 channel was a cation-selective channel, which was sensitive to GABA or β-alanine. The current of the Cs8916/LCCH3 channel was inhibited by dieldrin, endosulfan, fipronil, or ethiprole. In contrast, fluralaner, broflanilide, and avermectin showed little effect on the Cs8916/LCCH3 channel (IC50s > 10 000 nM). The Cs8916/RDL1 channel was sensitive to GABA, but was significantly different in EC50 and Imax for GABA to those of homomeric CsRDL1. Fluralaner, fipronil, or dieldrin showed antagonistic actions on Cs8916/RDL1. In conclusion, Cs8916 is a potential iGABA receptor subunit, which can interact with CsLCCH3 to generate a cation-selective channel that is sensitive to several insecticides. Also, as Cs8916/RDL1 has a higher EC50 than homomeric CsRDL1, Cs8916 may affect the physiological functions of CsRDL1 and therefore play a role in fine-tuning GABAergic signaling.
- Published
- 2021
35. Repair of Spinal Cord Injury by Inhibition of PLK4 Expression Through Local Delivery of siRNA-Loaded Nanoparticles
- Author
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Xin Xu, Xiangdong Chen, Runze Zhang, Yuan Zhou, Yingchu Gu, You Lang Zhou, Jun Jie Guan, Xing Jie Jiang, and Bin Jiang
- Subjects
Small interfering RNA ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,Western blot ,medicine ,Animals ,RNA, Small Interfering ,Spinal cord injury ,Spinal Cord Injuries ,Gene knockdown ,biology ,medicine.diagnostic_test ,Chemistry ,Kinase ,Recovery of Function ,General Medicine ,medicine.disease ,Spinal cord ,Rats ,Proliferating cell nuclear antigen ,Cell biology ,medicine.anatomical_structure ,Spinal Cord ,biology.protein ,Nanoparticles ,Astrocyte - Abstract
Polo-like kinase 4 (PLK4) is one of the key regulators of centrosomal replication. However, its role and mechanism in spinal cord injury (SCI) are still unclear. The SCI model on rats was constructed and the expression and localization of PLK4 in the spinal cord are analyzed with Western blot and immunofluorescence, respectively. Then the specific siRNAs were encapsulated in nanoparticles for the inhibition of PLK4 expression. Afterward, the role of PLK4 on astrocytes was investigated by knocking down its expression in the primary astrocytes. Moreover, siRNA-loaded nanoparticles were injected into the injured spinal cord of rats, and the motor function recovery of rats after SCI was assessed using the Basso, Beattie, and Bresnahan (BBB) locomotor scale method. Notably, the siRNA-loaded nanoparticles effectively transfect primary astrocytes and significantly inhibit PLK4 expression, together with the expression of PCNA with significance. After treatment, restoration of the motor function following SCI was significantly improved in the PLK4 knockdown group compared with the control group. Therefore, we speculate that inhibition of Plk4 may inhibit the proliferation of astrocytes and decrease the inflammatory response mediated by astrocytes, so as to promote the functional recovery of SCI. In conclusion, inhibition of PLK4 expression via siRNA-loaded nanoparticles may be a potential treatment for SCI.
- Published
- 2021
36. Perovskite La0.7Sr0.3Fe0.8B0.2O3 (B = Ti, Mn, Co, Ni, and Cu) as heterogeneous electrocatalysts for asymmetric electrocarboxylation of aromatic ketones
- Author
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Li-Rong Yang, Huan Wang, Rui Xiong, Cheng-Jie Jiang, Yi-Jun Zhao, and Jia-Xing Lu
- Subjects
Inorganic chemistry ,Aromatic ketones ,Catalysis ,Cathode ,law.invention ,Electron transfer ,chemistry.chemical_compound ,chemistry ,law ,Yield (chemistry) ,Physical and Theoretical Chemistry ,Enantiomeric excess ,Acetophenone ,Perovskite (structure) - Abstract
The perovskite oxides La0.7Sr0.3Fe0.8B0.2O3 (B = Ti, Mn, Co, Ni and Cu) synthesized by sol–gel method were used as cathodes and tested in asymmetric electrocarboxylation of aromatic ketones. The study showed the La0.7Sr0.3Fe0.8Ni0.2O3 (La7Sr3Fe8Ni2) catalyst is more active for asymmetric electrocarboxylation of acetophenone with 95% enantiomeric excess and 85% yield. The high electrocatalytic activity is attributed mainly to several factors, including the increased amount of lattice oxygen and Fe4+ species on the surface of La7Sr3Fe8Ni2, enhanced electrochemically active surface area and faster electron transfer. Furthermore, La7Sr3Fe8Ni2 also exhibited remarkable stability and reusability.
- Published
- 2021
37. Molecular cloning and sequence analysis of a mitogen-activated protein kinase gene in the Antarctic yeast Rhodotorula mucilaginosa AN5
- Author
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Yingying Wang, Y. L. Ju, C. H. Zhang, Cuijuan Shi, Kai Yu, Ziyi Cheng, Guangfeng Kan, Hong Zhang, and Jie Jiang
- Subjects
MAPK/ERK pathway ,biology ,MAP Kinase Signaling System ,Chemistry ,Kinase ,Rhodotorula ,Sequence Analysis, DNA ,General Medicine ,Molecular cloning ,Yeast ,Rhodotorula mucilaginosa ,Biochemistry ,Mitogen-activated protein kinase ,Genetics ,biology.protein ,Phosphorylation ,Amino Acid Sequence ,Cloning, Molecular ,Mitogen-Activated Protein Kinases ,Protein kinase A ,Molecular Biology ,Plant Proteins - Abstract
The mitogen-activated protein kinase (MAPK) cascades play important roles in various signaling transduction networks of biotic and abiotic stress responses. However, MAPK signaling pathways in cold-active yeast Rhodotorula mucilaginosa have not been reported comprehensively. In the present study, MAPK gene ( RmMAPK ) was first cloned and characterized from Antarctic sea ice yeast R. mucilaginosa AN5. The full length of the RmMAPK gene is 1086 bp and encodes a 361 amino acids protein with a predicted molecular mass of 40.9 kDa and a pI of 5.25. The RmMAPK contains 11 MAPK conserved subdomains and the phosphorylation motif TGY located in the activation loop of the kinase. Quantitative real-time PCR assay revealed that the expression of RmMAPK up-regulated rapidly and significantly when yeast cells were subjected to low temperature (4 °C), high salinity (120‰ NaCl) and heavy metal (2 mmol/L CuCl 2 ), which suggested that the RmMAPK might act as a key function in response to extreme stresses, such as low temperature, high salinity and heavy metal.
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- 2021
38. Discovery of a Potent Degrader for Fibroblast Growth Factor Receptor 1/2
- Author
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Tinghu Zhang, Wenchao Lu, Jie Jiang, Katherine A. Donovan, Jianwei Che, Guangyan Du, Hong Yue, Nabeel Bardeesy, Henning Nathaniel, Qibiao Wu, Eric S. Fischer, and Nathanael S. Gray
- Subjects
musculoskeletal diseases ,Protein degradation ,010402 general chemistry ,01 natural sciences ,Article ,Catalysis ,Cell Line, Tumor ,Drug Discovery ,medicine ,Humans ,Receptor, Fibroblast Growth Factor, Type 1 ,Receptor, Fibroblast Growth Factor, Type 2 ,biology ,010405 organic chemistry ,Chemistry ,Fibroblast growth factor receptor 1 ,Wild type ,Cancer ,General Medicine ,General Chemistry ,medicine.disease ,Ligand (biochemistry) ,Fusion protein ,0104 chemical sciences ,Ubiquitin ligase ,Fibroblast growth factor receptor ,Proteolysis ,embryonic structures ,biology.protein ,Cancer research - Abstract
Aberrant activation of FGFR signaling occurs in many cancers, and ATP-competitive FGFR inhibitors have received regulatory approval. Despite demonstrating clinical efficacy, these inhibitors exhibit dose-limiting toxicity, potentially due to a lack of selectivity amongst the FGFR family and are poorly tolerated. Here, we report the discovery and characterization of DGY-09-192, a bivalent degrader that couples the pan-FGFR inhibitor BGJ398 to a CRL2(VHL) E3 ligase recruiting ligand, which preferentially induces FGFR1&2 degradation while largely sparing FGFR3&4. DGY-09-192 exhibited two-digit nanomolar DC(50)s for both wildtype FGFR2 and several FGFR2-fusions, resulting in degradation-dependent antiproliferative activity in representative gastric cancer and cholangiocarcinoma cells. Importantly, DGY-09-192 induced degradation of a clinically relevant FGFR2 fusion protein in a xenograft model. Taken together, we demonstrate that DGY-09-192 has potential as a prototype FGFR degrader.
- Published
- 2021
39. Ligustrazine Attenuates Hyperhomocysteinemia-induced Alzheimer-like Pathologies in Rats
- Author
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Xi-Hu Qin, Juan Liu, Lin-Xiao Wang, Qing Zhang, Shi-Jie Jiang, Jing Wang, and Liang Zhu
- Subjects
Tau hyperphosphorylation ,Hyperhomocysteinemia ,Ligusticum chuanxiong ,Homocysteine ,Pharmacology ,Hippocampus ,Biochemistry ,Neuroprotection ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Alzheimer Disease ,Intragastric administration ,Genetics ,medicine ,Animals ,Humans ,Hippocampus (mythology) ,Phosphorylation ,Neurons ,Memory Disorders ,Amyloid beta-Peptides ,business.industry ,Alkaloid ,Brain ,medicine.disease ,Rats ,Disease Models, Animal ,Neuroprotective Agents ,chemistry ,Pyrazines ,business - Abstract
Ligustrazine, an alkaloid extracted from the traditional Chinese herbal medicine Ligusticum Chuanxiong Hort, has been clinically applied to treat the cerebrovascular diseases. Hyperhomocysteinemia (Hhcy) is an independent risk factor for Alzheimer's disease (AD). Memory deficits can be caused by Hhcy via pathologies of AD-like tau and amyloid-β (Aβ) in the hippocampus. Here, we investigated whether homocysteine (Hcy) can induce AD-like pathologies and the effects of ligustrazine on these pathologies. The Hcy rat model was constructed by 14-day Hcy injection via vena caudalis, and rats were treated with daily intragastric administration of ligustrazine at the same time. We found that the pathologies of tau and Aβ were induced by Hcy in the hippocampus, while the Hcy-induced tau hyperphosphorylation and Aβ accumulation could be markedly attenuated by simultaneous ligustrazine treatment. Our data demonstrate that ligustrazine may be used as a promising neuroprotective agent to treat the Hcy-induced AD-like pathologies.
- Published
- 2021
40. Construction of Porous Tubular In2S3@In2O3 with Plasma Treatment-Derived Oxygen Vacancies for Efficient Photocatalytic H2O2 Production in Pure Water Via Two-Electron Reduction
- Author
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Wenwen Zhang, Chunxian Zhang, Xi Chen, Jie Jiang, Luping Feng, Lixiang Zhang, and Hua Wang
- Subjects
Materials science ,Annealing (metallurgy) ,chemistry.chemical_element ,Quantum yield ,Heterojunction ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Oxygen ,0104 chemical sciences ,chemistry ,Chemical engineering ,Yield (chemistry) ,Photocatalysis ,General Materials Science ,0210 nano-technology ,Porosity ,Visible spectrum - Abstract
Tubular In2O3 was fabricated by the annealing of In-MIL-68 and further treated by Ar plasma to yield oxygen vacancies (Ov) followed by the growth of In2S3 nanoflowers. Unexpectedly, the resulting porous In2S3@In2O3 composites were discovered to display a broad visible-light response and especially enhanced capacities for efficient photocatalytic production of H2O2 in pure water, with a rate of 4.59 μmol·g-1·min-1. An apparent quantum yield of 28.9% at 420 nm can also be expected without the use of noble metals or organic scavengers. Herein, the high light utilization might be profited from their porous tubular heterostructure for powerful "light captivity". Moreover, the Ar plasma-derived Ov sites on the composites might tune the H2O2 generation route from the single-electron reduction to the two-electron one toward the significantly enhanced photocatalysis, as validated by the Koutecky-Levich plots. This work demonstrates a new perspective of designing porous heterostructures with the advantages of high light harvest and plasma-derived Ov active sites. Importantly, it may provide a promising defect-induced strategy of two-electron reduction triggered by the plasma treatment for the efficient photocatalytic H2O2 production under visible light.
- Published
- 2021
41. Fatostatin reverses progesterone resistance by inhibiting the SREBP1-NF-κB pathway in endometrial carcinoma
- Author
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Wei Lu, Kui Guo, Jie Jiang, Chunping Qiu, Tianyi Zhao, Hong Yan, Zhiming Liu, Lina Wei, and Xiaohong Ma
- Subjects
Cancer Research ,Pyridines ,Transcriptional regulatory elements ,Immunology ,Transfection ,Article ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Endometrium ,In vivo ,medicine ,Carcinoma ,Humans ,Regulatory Elements, Transcriptional ,Uterine Diseases ,QH573-671 ,Microarray analysis techniques ,business.industry ,Endometrial cancer ,NF-kappa B ,NF-κB ,Cell Biology ,medicine.disease ,In vitro ,Endometrial Neoplasms ,Thiazoles ,Cancer therapeutic resistance ,chemistry ,Cell culture ,Apoptosis ,Cancer research ,Female ,business ,Sterol Regulatory Element Binding Protein 1 ,Cytology - Abstract
Progesterone resistance can significantly restrict the efficacy of conservative treatment for patients with endometrial cancer who wish to preserve their fertility or those who suffer from advanced and recurrent cancer. SREBP1 is known to be involved in the occurrence and progression of endometrial cancer, although the precise mechanism involved remains unclear. In the present study, we carried out microarray analysis in progesterone-sensitive and progesterone-resistant cell lines and demonstrated that SREBP1 is related to progesterone resistance. Furthermore, we verified that SREBP1 is over-expressed in both drug-resistant tissues and cells. Functional studies further demonstrated that the inhibition of SREBP1 restored the sensitivity of endometrial cancer to progesterone both in vitro and in vivo, and that the over-expression of SREBP1 promoted resistance to progesterone. With regards to the mechanism involved, we found that SREBP1 promoted the proliferation of endometrial cancer cells and inhibited their apoptosis by activating the NF-κB pathway. To solve the problem of clinical application, we found that Fatostatin, an inhibitor of SREBP1, could increase the sensitivity of endometrial cancer to progesterone and reverse progesterone resistance by inhibiting SREBP1 both in vitro and in vivo. Our results highlight the important role of SREBP1 in progesterone resistance and suggest that the use of Fatostatin to target SREBP1 may represent a new method to solve progesterone resistance in patients with endometrial cancer.
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- 2021
42. Exosomal DLX6-AS1 from hepatocellular carcinoma cells induces M2 macrophage polarization to promote migration and invasion in hepatocellular carcinoma through microRNA-15a-5p/CXCL17 axis
- Author
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Linpei Wang, Jing Lin, Xiao-qiu Ma, Chun-feng Shi, Xiao-jie Jiang, Dong-yao Xu, and Wei Wang
- Subjects
Male ,Cancer Research ,Chemokine ,Carcinoma, Hepatocellular ,Hepatocellular carcinoma ,Mice, Nude ,Long non-coding RNA distal-less homeobox 6 antisense 1 ,Exosomes ,Mice ,Cell Movement ,microRNA ,Animals ,Humans ,Hepatocellular carcinoma cell-secreted exosomes ,M2 macrophages ,Neoplasm Invasiveness ,C-X-C motif chemokine ligand 17 ,Epithelial–mesenchymal transition ,neoplasms ,RC254-282 ,CXCL17 ,biology ,Chemistry ,Macrophages ,Liver Neoplasms ,Cell Polarity ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Cell migration ,M2 Macrophage ,Microvesicles ,digestive system diseases ,microRNA-15a-5p ,MicroRNAs ,Oncology ,Apoptosis ,Cancer research ,biology.protein ,RNA, Long Noncoding ,Chemokines, CXC ,Signal Transduction - Abstract
Background Hepatocellular carcinoma (HCC) cells-secreted exosomes (exo) could stimulate M2 macrophage polarization and promote HCC progression, but the related mechanism of long non-coding RNA distal-less homeobox 6 antisense 1 (DLX6-AS1) with HCC-exo-mediated M2 macrophage polarization is largely ambiguous. Thereafter, this research was started to unearth the role of DLX6-AS1 in HCC-exo in HCC through M2 macrophage polarization and microRNA (miR)-15a-5p/C-X-C motif chemokine ligand 17 (CXCL17) axis. Methods DLX6-AS1, miR-15a-5p and CXCL17 expression in HCC tissues and cells were tested. Exosomes were isolated from HCC cells with overexpressed DLX6-AS1 and co-cultured with M2 macrophages. MiR-15a-5p/CXCL17 down-regulation assays were performed in macrophages. The treated M2 macrophages were co-cultured with HCC cells, after which cell migration, invasion and epithelial mesenchymal transition were examined. The targeting relationships between DLX6-AS1 and miR-15a-5p, and between miR-15a-5p and CXCL17 were explored. In vivo experiment was conducted to detect the effect of exosomal DLX6-AS1-induced M2 macrophage polarization on HCC metastasis. Results Promoted DLX6-AS1 and CXCL17 and reduced miR-15a-5p exhibited in HCC. HCC-exo induced M2 macrophage polarization to accelerate migration, invasion and epithelial mesenchymal transition in HCC, which was further enhanced by up-regulated DLX6-AS1 but impaired by silenced DLX6-AS1. Inhibition of miR-15a-5p promoted M2 macrophage polarization to stimulate the invasion and metastasis of HCC while that of CXCL17 had the opposite effects. DLX6-AS1 mediated miR-15a-5p to target CXCL17. DLX6-AS1 from HCC-exo promoted metastasis in the lung by inducing M2 macrophage polarization in vivo. Conclusion DLX6-AS1 from HCC-exo regulates CXCL17 by competitively binding to miR-15a-5p to induce M2 macrophage polarization, thus promoting HCC migration, invasion and EMT.
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- 2021
43. Facile Preparation of Binary Salt Hydrates/Carbon Nanotube Composite for Thermal Storage Materials with Enhanced Structural Stability
- Author
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Die Hu, Jie Jiang, Xuesong Yang, Peng Li, Huacheng Wu, Weiqing Zhou, and Xilai Jia
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chemistry.chemical_classification ,Materials science ,Composite number ,Energy Engineering and Power Technology ,Salt (chemistry) ,Carbon nanotube ,Thermal energy storage ,law.invention ,Thermal conductivity ,Chemical engineering ,chemistry ,law ,Structural stability ,Materials Chemistry ,Electrochemistry ,Chemical Engineering (miscellaneous) ,Electrical and Electronic Engineering - Abstract
Large-scale distributed thermal storage requires high-energy-density and low-cost thermal storage materials. Here, a concocted composite composed of Al2(SO4)3·18H2O and FeSO4·7H2O salts, as well as...
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- 2021
44. Atmospheric-Pressure Plasma Jet-Induced Ultrafast Construction of an Ultrathin Nonstoichiometric Nickel Oxide Layer with Mixed Ni3+/Ni2+ Ions and Rich Oxygen Defects as an Efficient Electrocatalyst for Oxygen Evolution Reaction
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Xiaonan Shang, Zhongqing Jiang, Changsheng Song, Baoan Zhang, Zhong-Jie Jiang, and Thandavarayan Maiyalagan
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Jet (fluid) ,animal structures ,Materials science ,Nickel oxide ,Oxygen evolution ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Atmospheric-pressure plasma ,Electrocatalyst ,complex mixtures ,Oxygen ,chemistry ,Chemical engineering ,Materials Chemistry ,Electrochemistry ,Chemical Engineering (miscellaneous) ,Water splitting ,natural sciences ,Electrical and Electronic Engineering ,Layer (electronics) - Abstract
An approach, i.e., atmospheric-pressure nonequilibrium oxygen plasma jet technology, has been reported for the first time to in situ prepare ultrathin nonstoichiometric nickel oxide layers with mix...
- Published
- 2021
45. Structural and kinetic characterization of Porphyromonas gingivalis glutaminyl cyclase
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Jie Jiang, Sihong Yu, Bo Sun, David Ruiz-Carrillo, Sebastiaan Lamers, Qiaoli Feng, Maxwell Lukman, and Yili Cheng
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0301 basic medicine ,Peptide Metabolism ,Rossmann fold ,030102 biochemistry & molecular biology ,Amyloid ,biology ,Chemistry ,Clinical Biochemistry ,biology.organism_classification ,Biochemistry ,Small molecule ,Pathogenesis ,03 medical and health sciences ,030104 developmental biology ,Drug development ,Beta (finance) ,Molecular Biology ,Porphyromonas gingivalis - Abstract
Porphyromonas gingivalis is a bacterial species known to be involved in the pathogenesis of chronic periodontitis, that more recently has been as well associated with Alzheimer’s disease. P. gingivalis expresses a glutaminyl cyclase (PgQC) whose human ortholog is known to participate in the beta amyloid peptide metabolism. We have elucidated the crystal structure of PgQC at 1.95 Å resolution in unbound and in inhibitor-complexed forms. The structural characterization of PgQC confirmed that PgQC displays a mammalian fold rather than a bacterial fold. Our biochemical characterization indicates that PgQC uses a mammalian-like catalytic mechanism enabled by the residues Asp149, Glu182, Asp183, Asp218, Asp267 and His299. In addition, we could observe that a non-conserved Trp193 may drive differences in the binding affinity of ligands which might be useful for drug development. With a screening of a small molecule library, we have identified a benzimidazole derivative rendering PgQC inhibition in the low micromolar range that might be amenable for further medicinal chemistry development.
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- 2021
46. <scp> Mycobacterium tuberculosis </scp> puromycin hydrolase displays a prolyl oligopeptidase fold and an acyl aminopeptidase activity
- Author
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Jie Jiang, Yan Zhang, Xiao Zhou, Maxwell Lukman, David Ruiz-Carrillo, Qiaoli Feng, and YuanHao Zhao
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Models, Molecular ,Protein Conformation, alpha-Helical ,Proline ,Hydrolases ,Phenylalanine ,Genetic Vectors ,Gene Expression ,Oligopeptidase ,Crystallography, X-Ray ,Aminopeptidases ,Biochemistry ,Aminopeptidase ,Substrate Specificity ,Mycobacterium tuberculosis ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Leucine ,Structural Biology ,Catalytic Domain ,Hydrolase ,Escherichia coli ,Protein Interaction Domains and Motifs ,Cloning, Molecular ,Molecular Biology ,030304 developmental biology ,Alanine ,chemistry.chemical_classification ,0303 health sciences ,biology ,Chemistry ,030302 biochemistry & molecular biology ,Active site ,biology.organism_classification ,Recombinant Proteins ,Kinetics ,Enzyme ,Puromycin ,biology.protein ,Protein Conformation, beta-Strand ,Prolyl Oligopeptidases ,Hydrophobic and Hydrophilic Interactions ,Protein Binding - Abstract
Puromycin-hydrolizing peptidases have been described as members of the prolyl oligopeptidase peptidase family. These enzymes are present across all domains of life but still little is known of the homologs found in the pathogenic bacterium Mycobacterium tuberculosis. The crystal structure of a M. tuberculosis puromycin hydrolase peptidase has been determined at 3 Angstrom resolution, revealing a conserved prolyl oligopeptidase fold, defined by α/β-hydrolase and β-propeller domains with two distinctive loops that occlude access of large substrates to the active site. The enzyme displayed amino peptidase activity with a substrate specificity preference for hydrophobic residues in the decreasing order of phenylalanine, leucine, alanine and proline. The enzyme's active site is lined by residues Glu564 for the coordination of the substrates amino terminal moiety and His561, Val608, Tyr78, Trp306, Phe563 and Ty567 for the accommodation of hydrophobic substrates. The availability of a crystal structure for puromycin hydrolase of M. tuberculosis shall facilitate the development of inhibitors with therapeutic applications.
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- 2021
47. Chiral deformation reversal of liquid crystal polymer actuators
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Zhi-Chao Jiang, Yue Zhao, Lu Yin, Yao-Yu Xiao, and Jie Jiang
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chemistry.chemical_classification ,Quantitative Biology::Biomolecules ,geography ,Materials science ,geography.geographical_feature_category ,Mesogen ,02 engineering and technology ,General Chemistry ,Polymer ,Deformation (meteorology) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry ,Orientation (geometry) ,Materials Chemistry ,Reversing ,Composite material ,Monolith ,0210 nano-technology ,Actuator ,Realization (systems) - Abstract
The chiral deformation of a conventional helical actuator is unidirectional in each activation (stimuli-on) process and in each recovery (stimuli-off) process, which means that the twisting direction remains the same regardless of the nature of deformation (either winding or unwinding or helix-inversion). In these cases, a complete stimuli-switching cycle is necessary for the realization of a bidirectional helical deformation process that comprises a reversal of twisting direction. Here, we achieved bidirectional and even multi-directional helical shape evolution in each stimuli-on (or off) process. The strategy relies on, on one hand, asymmetrically crosslinking and/or elongating the two sides of a photocrosslinkable liquid crystal polymer (LCP) monolith, and on the other hand, tailoring the uniaxially aligned polymer strip to form an off-axis mesogen orientation. We obtained a wide variety of helical actuators capable of reversing their twisting directions by only cooling (or heating). The mechanisms of these various chiral deformation-reversal behaviours and the two observed reversals of the twisting direction during cooling have been elucidated.
- Published
- 2021
48. The Kirkendall effect-induced formation of FeP@C composites comprising interconnected carbon-coated hollow FeP sub-nanoparticles for efficient alkaline metal storage
- Author
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Liping Guo, Zhongqing Jiang, Yanmin Qin, and Zhong-Jie Jiang
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Materials science ,Kirkendall effect ,Renewable Energy, Sustainability and the Environment ,Diffusion ,Composite number ,Nanoparticle ,chemistry.chemical_element ,General Chemistry ,Alkali metal ,Redox ,Chemical kinetics ,Chemical engineering ,chemistry ,General Materials Science ,Carbon - Abstract
Structural features are important factors determining the performance of electrode materials for alkaline metal (Li, Na, and K) storage. In this work, we report a fascinating Kirkendall-effect-based method for the synthesis of a spindle-like FeP@C composite with a hierarchical structure comprising carbon-coated hollow FeP sub-nanoparticles (S-HFeP@C). In such a unique structure, the interconnected carbon network and intimate C/FeP contact allow for the ready transfer of charge during redox reactions. The hollow structure of the FeP nanoparticles and their thin walls allow for easy ion diffusion and satisfactory alleviation of the overall strain of FeP, endowing S-HFeP@C with fast reaction kinetics, satisfactory utilization of active material, and excellent structural robustness upon redox reaction. Enhanced performance was observed for Li, Na, and K storage by S-HFeP@C, consisting of a high specific capacity, excellent rate capabilities, and satisfactory cycling stability.
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- 2021
49. Enantioselective synthesis of 1-aminoindene derivatives via asymmetric Brønsted acid catalysis
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Tao Wang, Hua-Jie Jiang, Du Ding, Ying Zhang, Li-Ping Zhao, and Xiang Wu
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Chemistry ,Metals and Alloys ,Enantioselective synthesis ,Iminium ,General Chemistry ,Combinatorial chemistry ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Ion ,chemistry.chemical_compound ,Enantiopure drug ,Materials Chemistry ,Ceramics and Composites ,Phosphoramide ,Brønsted–Lowry acid–base theory - Abstract
We describe a catalytic asymmetric iminium ion cyclization reaction of simple 2-alkenylbenzaldimines using a BINOL-derived chiral N-triflyl phosphoramide. The corresponding 1-aminoindenes and tetracyclic 1-aminoindanes are formed in good yields and high enantioselectivities. Further, the chemical utility of the obtained enantiopure 1-aminoindene is demonstrated for the asymmetric synthesis of (S)-rasagiline.
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- 2021
50. Unoccupied 3d orbitals make Li-unalloyable transition metals usable as anode materials for lithium ion batteries
- Author
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Zhongqing Jiang, Zhong-Jie Jiang, and Liping Guo
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Materials science ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Nanoparticle ,chemistry.chemical_element ,General Chemistry ,law.invention ,Anode ,Ion ,Adsorption ,chemistry ,Transition metal ,law ,General Materials Science ,Lithium ,Calcination ,Carbon - Abstract
It is generally believed that metals which are unalloyable with Li are not active for Li storage. This work, however, demonstrates that transition metals with unoccupied 3d orbitals are usable as anode materials for Li storage although they are unalloyable with Li. Specifically, we synthesize spindle-shaped Fe@C (S-Fe@C) by the calcination of an Fe based metal–organic framework, which comprises carbon coated Fe subnanoparticles with an interconnected carbon network. When used in LIBs, S-Fe@C can exhibit a stable reversible capacity of 967.3 ± 16.2 mA h g−1 at 100 mA g−1. More interestingly, when S-Fe@C with smaller Fe nanoparticles and more spacing between the Fe nanoparticles and carbon shell is used as the anode for LIBs, the stable reversible capacity can reach up to 1091.9 ± 17.6 mA h g−1 at 100 mA g−1 after 100 cycles. The in operando XRD patterns exclude the contribution of capacities from the alloying between Fe and Li. DFT calculations indicate that the unoccupied 3d orbitals of Fe atoms can accept electrons from Li, which makes the surface of Fe nanoparticles highly active for Li adsorption. The Li adsorption can be multi-layered. Our findings can well explain why some transition metal oxides can exhibit extra capacities beyond their theoretical capacities.
- Published
- 2021
Catalog
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