157 results on '"Qu, Wen"'
Search Results
2. Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis
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Qu, Wen-Yuan, Zhou, Xue-Song, Xiao, Wen-Jing, and Chen, Jia-Rong
- Abstract
Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.
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- 2024
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3. A Temperature-Sensitive Fluorescent Supramolecular Polymer Constructed by Discrete Platinum(II) Metallacycle and Pillar[5]arene-Based Host–Guest Interactions
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Hu, Wentao, Wang, Ke, Li, Xupeng, Fan, Xiliang, Qu, Wen-Juan, Wei, Tai-Bao, Lin, Qi, and Shi, Bingbing
- Abstract
The application of thermosensitive fluorescent supramolecular polymers in advanced optical materials, chemical sensors, artificial optical devices, and external stimulus responses remains underdeveloped. In this study, we introduced a novel method for constructing a mechanically interlocked fluorescent supramolecular polymer utilizing host–guest interactions, including C–H···π interactions and π–π stacking. This polymer exhibits outstanding temperature-sensitive fluorescence properties and is environmentally friendly due to its recyclability. Leveraging the polymer’s fluorescence response at critical temperature ranges, we developed a high-temperature warning device. This device utilizes the temperature-sensitive fluorescence characteristic of the polymer to indicate dangerous temperature levels, thereby demonstrating its potential in practical safety applications.
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- 2024
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4. Global Justice Index Report 2023
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Gu, Yanfeng, Guo, Sujian, Gan, Yiqing, Qin, Xuan, Qu, Wen, Wang, Zhongyuan, and Zhang, Tiantian
- Abstract
The Global Justice Index is a multiyear research project based at Fudan Institute for Advanced Study in Social Sciences that assesses the contributions made by each country to achieving greater global justice. We have published results for yeas from 2010 to 2020 in Global Justice Index Reportfrom 2019 to 2022, and are now presenting our fifth year of results, covering data from 2021 in Global Justice Index Report 2023, which is an updated version of previous years’ reports. But, we have been improving our index year by year to with changes that have taken place globally. We have also refined our imputation methodology to better address the challenge of missing data. The report consists of four sections: introduction, findings, main results, and conclusion. In the introduction, we discuss the development of the conceptual framework and evaluative principles to justify our selection of the dimensions and indicators for measurement. Next, in the findings section, we report the data, indicators, and our results for each country for each of the 10 issues we identify, and provide regional comparisons for Asia, Europe, North America, Latin America, Africa, and Oceania. In the following section, we present the main results for the global justice indices, and report the ranking of each country’s contribution to achieving greater global justice. In the final section, we discuss the applications and limitations of the index and potential further research trajectories.
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- 2024
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5. Performance test of commercial InGaAs detectors in low temperature
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Holland, Andrew D., Minoglou, Kyriaki, Ma, Hao-ran, Qu, Wen-qing, Ning, Yu, Wei, Jiang-yuan, Gao, Jie, Zhang, Hong-fei, and Wang, Jian
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- 2024
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6. Firmware design of a science CMOS camera and its performance test
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Holland, Andrew D., Minoglou, Kyriaki, Liu, Zi-yi, Zhang, Yi-hao, Tang, Yu-jing, Qu, Wen-qing, Gao, Jie, Zhang, Hong-fei, and Wang, Jian
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- 2024
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7. Design and Test of a Time-to-Digital Converter ASIC Based on a Differential Delay Line
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Gao, Jie, Yang, Dong-Xu, Wang, Jian, Qu, Wen-Qing, Jiang, Wei-Jie, Feng, Yi, Wang, Zhi-Yue, and Zhang, Hong-Fei
- Abstract
As one of the main components of a high-precision time measurement system, the time-to-digital converter (TDC) is widely used in many scientific research fields. A two-stage high-precision and wide-range TDC application-specified integrated circuit (ASIC) based on a differential delay line using delay-locked loop (DLL) technology is presented. The TDC ASIC consists of a coarse measurement stage for expanding the measurement range and a fine measurement stage for high-precision measurement. The coarse stage is achieved by two binary counters with dual edges sampling to avoid the metastable state. The fine stage is achieved by a voltage-controlled delay line (VCDL). The VCDL utilizes differential delay cells to mitigate the susceptibility to the power supply noise and the substrate noise. A DLL is adopted to compensate for variations in process, voltage, and temperature (PVT). The TDC AISC has been fabricated in a 180-nm CMOS technology and tested. A dynamic measurement range of
$6.55~\mu $ - Published
- 2024
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8. Clamparene: Synthesis, Structure, and Its Application in Spontaneous Formation of 3D Porous Crystals.
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Shi, Bingbing, Jiang, Jingxiong, An, Hui, Qi, Lijuan, Wei, Tai-Bao, Qu, Wen-Juan, and Lin, Qi
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- 2024
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9. Enantioselective Cyanofunctionalization of Aromatic Alkenes via Radical Anions.
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Zhang, Bin, Li, Tian-Tian, Mao, Zhi-Cheng, Jiang, Min, Zhang, Zhihan, Zhao, Ke, Qu, Wen-Yuan, Xiao, Wen-Jing, and Chen, Jia-Rong
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- 2024
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10. Enantioselective Cyanofunctionalization of Aromatic Alkenes via Radical Anions
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Zhang, Bin, Li, Tian-Tian, Mao, Zhi-Cheng, Jiang, Min, Zhang, Zhihan, Zhao, Ke, Qu, Wen-Yuan, Xiao, Wen-Jing, and Chen, Jia-Rong
- Abstract
Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.
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- 2024
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11. Comparison of the K1 Rule, Parallel Analysis, and the Bass-Ackward Method on Identifying the Number of Factors in Factor Analysis
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Tong, Lingbo, Qu, Wen, and Zhang, Zhiyong
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Factor analysis is widely utilized to identify latent factors underlying the observed variables. This paper presents a comprehensive comparative study of two widely used methods for determining the optimal number of factors in factor analysis, the K1 rule, and parallel analysis, along with a more recently developed method, the bass-ackward method. We provide an in-depth exploration of these techniques, discussing their historical development, advantages, and limitations. Using a series of Monte Carlo simulations, we assess the efficacy of these methods in accurately determining the appropriate number of factors. Specifically, we examine two cessation criteria within the bass-ackward framework: BA-maxLoading and BA-cutoff. Our findings offer nuanced insights into the performance of these methods under various conditions, illuminating their respective advantages and potential pitfalls. To enhance accessibility, we create an online visualization tool tailored to the factor structures generated by the bass-ackward method. This research enriches the understanding of factor analysis methodology, assists researchers in method selection, and facilitates comprehensive interpretation of latent factor structures.
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- 2024
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12. A Two-Step Fluorescence-Resonance Energy Transfer System Constructed by Platinum(II) Metallacycle Based Molecular Recognition.
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Shi, Bingbing, Qin, Peng, Li, Weichun, Feng, Hua, Zhou, Yi, Chai, Yongping, Qu, Wen-Juan, Wei, Tai-Bao, Zhang, You-Ming, and Lin, Qi
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- 2023
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13. Asymmetric [3 + 2] Photocycloaddition of β‑Keto Esters and Vinyl Azides by Dual Photoredox/Nickel Catalysis.
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Zhou, Xue-Song, Zhang, Zhihan, Qu, Wen-Yuan, Liu, Xiao-Peng, Xiao, Wen-Jing, Jiang, Min, and Chen, Jia-Rong
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- 2023
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14. Tumor cell membrane remodeling with universal ligand for CAR-T cells to inhibit solid tumors
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Fan, Jin-Xuan, Hu, Zhong-Bao, Gu, Hui-Yun, Qu, Wen-Qiang, Li, Wen, Qi, Bai-Wen, Yu, Ai-Xi, and Zhang, Xian-Zheng
- Abstract
Heterogeneity is a major obstacle to the success of CAR-T therapy in treating solid tumors. The complex tumor microenvironment and varying phenotypes of tumor cells might result in antigen escape, drug resistance, and tumor recurrence. To address this issue, we proposed to use lipid-modified fluorescein isothiocyanate (Lip-FITC) as an artificial ligand to normalize the phenotypes of solid tumor cells. In murine cutaneous melanoma and colon adenocarcinoma that prefer to utilize exogenous long-chain fatty acids, we observed much more uptake of Lip-FITC and significantly increased FITC fluorescence on tumor cell membranes than normal cells. This specific exogenous labeling with FITC enhanced the recognition and selectivity of CART cells in solid tumors, bypassing the limitations derived from antigen expression differences in adoptive cell therapies. Lipid metabolism analysis and in vitroexperiments demonstrated the sufficient uptake of long-chain fatty acid (LCFAs)-modified Lip-FITC by solid tumor cells, as well as satisfactory ligand assembly on cell membranes. In solid tumor model, the treatment induced the recognition and initiation of CART cells and successfully suppressed tumor progression through T-cell immunity.
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- 2023
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15. Asymmetric [3 + 2] Photocycloaddition of β-Keto Esters and Vinyl Azides by Dual Photoredox/Nickel Catalysis
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Zhou, Xue-Song, Zhang, Zhihan, Qu, Wen-Yuan, Liu, Xiao-Peng, Xiao, Wen-Jing, Jiang, Min, and Chen, Jia-Rong
- Abstract
Photocatalytic [3 + 2] cycloadditions and control of stereochemistry have remained a substantial challenge, particularly in the context of heterocycle synthesis; sporadic successful examples have involved enantioselective [3 + 2] photocycloaddition between redox-active direct group-containing cyclopropanes and alkenes for creation of cyclopentanes. Herein, we report a cooperative catalytic system comprising a chiral nickel Lewis acid catalyst and an organic photocatalyst fueled by visible-light irradiation that allows for the hitherto elusive asymmetric [3 + 2] photocycloaddition of β-keto esters with vinyl azides under redox-neutral conditions. This protocol enables highly enantioselective construction of polycyclic densely substituted 3,4-dihydro-2H-pyrrole heterocycles featuring two contiguous tetrasubstituted carbon stereocenters, including a useful chiral N,O-ketal motif that is not easily accessible with other catalytic methods. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of dual roles of nickel catalysts by the catalytic formation of the substrate/Ni complex, assisting both photoredox event and enantioselective radical addition.
- Published
- 2023
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16. Global Justice Index Report 2022
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Gu, Yanfeng, Guo, Sujian, Qin, Xuan, Qu, Wen, Wang, Zhongyuan, and Zhang, Tiantian
- Abstract
The Global Justice Index is a multiyear research project based at Fudan Institute for Advanced Study in Social Sciences that assesses the contributions made by each country to achieving greater global justice. We have published results from 2010 to 2019 in Global Justice Index Report, Global Justice Index Report 2020, Global Justice Index Report 2021, and we are now presenting our fourth-year results for 2020 in Global Justice Index Report 2022, which is an updated version of previous years’ reports. This year, we take into account changes to global justice influenced by the COVID-19 pandemic. The report consists of four sections: introduction, findings, main results, and conclusion. In the introduction, we discuss the development of the conceptual framework and evaluative principles to justify our selection of the dimensions and indicators for measurement. Next, in the findings section, we report the data, indicators, and our results for each country for each of the 10 issues we identify, and provide regional comparisons for Asia, Europe, North America, Latin America, Africa, and Oceania. In the following section, we present the main results for the global justice indices, and report the ranking of each country’s contribution to achieving greater global justice. In the final section, we discuss the applications and limitations of the index and potential further research trajectories.
- Published
- 2023
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17. Ankle Arthrodesis Combined With Mosaic Bone Autograft Transplantation for End-Stage Ankle Osteoarthritis With Large Cysts of Talar Dome.
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Liu, Tong, Dong, Sheng-jie, Li, Wen-liang, Wang, Dan, Zheng, Yan-ping, and Qu, Wen-qing
- Abstract
End-stage ankle osteoarthritis with large cysts of talar dome can be challenging to treat. Twenty patients diagnosed as end-stage ankle arthritis with large talar cysts between 04/2010 and 02/2016 were randomly divided into experimental group (10 cases) and conventional group (10 cases) by random number method. Patients in the experimental group were treated with ankle arthrodesis combined with a concomitant procedure of mosaic bone autograft transplantation, the conventional group under the ankle arthrodesis. The operation time, intraoperative blood loss, postoperative hospital stay, the time of bone union, and postoperative height of the talus between the 2 groups were compared. The preoperative and postoperative American Orthopaedic Foot and Ankle Society ankle-hindfoot scale score were also recorded and compared. There was no significant difference in the operation time, intraoperative blood loss, and postoperative hospital stay between the 2 groups. The postoperative height of the talus body and the time of bone union were better in the experimental group than that in the conventional group (p <.05). The results of follow-up showed that the American Orthopaedic Foot and Ankle Society scores of the conventional group were lower than those in the experimental group (p <.001). And the incidence of complication (10%) in the experimental group was significantly lower than that in the conventional group (40%). The use of tibiotalar arthrodesis combined with mosaic bone autograft transfer may be potentially an effective option for the treatment of end-stage ankle arthritis with large talar cysts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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18. Diversity of soil seed banks under different vegetation types in the southeastern margin of the Tengger Desert, China.
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SUN Yu-shuo, CHANG Xuan-xuan, ZHANG Xue, WANG Lei, QU Wen-jie, QIN Wei-chun, ZHANG Bo, and NIU Jin-shuai
- Abstract
To explore the dynamics and distribution of soil seed banks under different vegetation types in desert, and reveal the community succession tendency and diversity characteristics of different vegetative types, we took Populus euphratica community, Caragana intermedia community, Leymus secalinus community and Agriophyllum squarrosum community as the research objects in the southeastern margin of the Tengger Desert. Samples of 0-2 cm, 2-5 cm, 5-10 cm, and 10-20 cm soil layers were collected. We examined the characteristics of soil seed banks and their relationships with vegetation. The results showed that there were 13 plant species in the soil seed banks of the four vegetation types, belonging to 3 families and 12 genera, with the annual and biennial herbs dominated and much Chenopodiaceae species. The soil seed bank density was generally low, with an order of C. intermedia community > L. secalinus community > P. euphratica community > A. squarrosum community. The seed bank density and species richness decreased with increasing soil depth. Based on the Shannon index, Simpson index, Pielou index and Patrick richness analysis, the order of species diversity in soil seed banks was P. euphratica community > L. secalinus community > C. intermedia community > A. squarrosum community. The similarity coefficient between soil seed bank and vegetation was the highest in C. intermedia community, followed by P. euphratica community, and the lowest in P. euphratica community and L. secalinus community. On the whole, the arbor forest P. euphratica community was the most stable one, while the sandy land A. squarrosum community was the most vulnerable. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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19. A supramolecular oligo[2]rotaxane constructed by orthogonal platinum(II) metallacycle and pillar[5]arene-based host–guest interactions
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Shi, Bingbing, Wang, Yuchun, Zhou, Yi, Zhao, Xing-Xing, Li, Yizhou, Yan, Nuoqian, Qu, Wen-Juan, Lin, Qi, and Wei, Tai-Bao
- Abstract
Oligo[n]rotaxanes are one of the most extensively studied categories of mechanically bonded macromolecules. In this study, a supramolecular oligo[2]rotaxane is successfully constructed driven by platinum(II) metallacycle and pillar[5]arene-based host–guest interactions in an orthogonal way. The supramolecular oligo[2]rotaxane is further applied in fabricating a light harvesting system.
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- 2024
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20. An Organoplatinum(II) Metallacycle-Based Supramolecular Amphiphile and Its Application in Enzyme-Responsive Controlled Release.
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Shi, Bingbing, Qin, Peng, Chai, Yongping, Qu, Wen-Juan, Shangguan, Liqing, Lin, Qi, Zhang, You-Ming, Sun, Yan, Huang, Feihe, and Stang, Peter J.
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- 2022
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21. Temperature control and vibration measurement of a MCT camera using a tube cyrocooler
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Navarro, Ramón, Jedamzik, Ralf, Wei, Jiang-yuan, Qu, Wen-qing, Zeng, Feng, Ma, Hao-ran, Ning, Yu, Zhang, Hong-fei, and Wang, Jian
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- 2024
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22. Design of a 1x3 mosaic infrared camera in the K-band based on HgCdTe detectors
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Bryant, Julia J., Motohara, Kentaro, Vernet, Joël R. D., Qu, Wen-qing, Wei, Jiang-yuan, Ma, Hao-ran, Ning, Yu, Geng, Zhe, Zhang, Yu, Zeng, Feng, Zhang, Hong-fei, and Wang, Jian
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- 2024
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23. An Organoplatinum(II) Metallacycle-Based Supramolecular Amphiphile and Its Application in Enzyme-Responsive Controlled Release
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Shi, Bingbing, Qin, Peng, Chai, Yongping, Qu, Wen-Juan, Shangguan, Liqing, Lin, Qi, Zhang, You-Ming, Sun, Yan, Huang, Feihe, and Stang, Peter J.
- Abstract
Enzyme-responsive nanomaterials are emerging as important candidates for bioanalytical and biomedical applications due to their good biocompatibilities and sensitivities. However, the lack of promising operation platforms compatible with enzyme responsiveness greatly limits the scope and functionality of smart materials. Herein, we report the design and synthesis of a naphthalene-functionalized organoplatinum(II) metallacycle 1by means of coordination-driven self-assembly, which is subsequently exploited as the organometallic platform to enable enzyme-responsive supramolecular materials. Specifically, a [2 + 2] self-assembled metallacycle 1first self-assembles into nanosheets in aqueous solution, which can further transform into vesicles with the introduction of β-cyclodextrin (β-CD) because of the formation of a bola-type supramolecular amphiphile β-CD-1. Interestingly, these vesicles show rare α-amylase responsiveness, as demonstrated by structurally transforming back into nanosheets after the addition of α-amylase to their solutions due to the enzyme-induced degradation of cyclodextrins. We also demonstrate the potential application of the self-assembled vesicles in amylase-responsive controlled release.
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- 2022
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24. Preparation of Semi-Solid 357.0 Slurries with Different α-Al Phase Features by Solidification from Full Liquid State and Remelting
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Chen, Juan, Hu, Xiao Gang, Qu, Wen Ying, Luo, Min, Li, Zhong, Dong, En Jie, and Zhu, Qiang
- Abstract
The characteristics of the solid phase, namely the volume fraction, particle size, and morphology, are dominant variables that can determine the viscosity of the semi-solid slurry. However, particle size and morphology were always being ignored and the solid fraction was simply determined using the temperature in the conventional power-law viscosity, resulting in a disagreement in the viscosity values in different researches. To make the power-law viscosity model more accurate for predicting the filling process of semi-solid die casting, it is essential to modify this viscosity model based on particle characteristics. Therefore, there is a fundamental demand to prepare semi-solid slurries with different α-Al phase features at first. This is achieved in this study by two kinds of heat history controlling methods: remelting and solidification, which can get slurries with spherical structure and dendric structure, respectively. The semi-solid 357.0 slurries with 0.11-0.43 solid fraction, 137-182μm particle size, and 0.81-0.90 shape factor were prepared in the remelting process, while dendritic structures (shape factor<0.5) with 0.1 and 0.3 solid fractions were obtained by solidification controlling from the full liquid state. Besides, the effect of parameters on the evolution of the α-Al phase has been discussed. These slurries with different solid features will be further used to quantify the influence of primary phase characteristics on rheological behavior and make the power-law viscosity model more accurate for simulation.
- Published
- 2022
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25. Progress of Semi-Solid Processing of Alloys and Composites in China
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Li, Gan, Luo, Min, Qu, Wen Ying, Lu, Hong Xing, Hu, Xiao Gang, and Zhu, Qiang
- Abstract
Following the rapid growth of the automotive and communication industries, components with high quality and low cost are eagerly desired in China. Various technologies have been developed in China to meet the demand, while semi-solid processing (SSP) of alloys and composites is one of the most successfully developed and practically applied technologies. The major SSP applied in China is the rheocasting in terms of the Swirled Enthalpy Equilibration Device (SEED) process. In this review, we start with a brief reviewing some common slurry preparation methods and recent innovations of the SEED process. Subsequently, we describe the general situation and some recent examples of successful development and applications of SSP in China. Lastly, the future directions in SSP of alloys and composites are highlighted in this frontier research field at the end of this review.
- Published
- 2022
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26. Effects of Grain Morphology on Flow Behavior of Semi-Solid Slurries
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Luo, Min, Li, Da Quan, Lu, Hong Xing, Qu, Wen Ying, Zhang, Hong, Cheng, Le, and Zhu, Qiang
- Abstract
The flow behavior of semi-solid slurry determines the quality of the castings produced by the semi-solid forming process. Many studies have done to investigate the flow behavior of slurry under different conditions, and results show that the rheological behavior of slurry with dendritic structure is inappropriate for semi-solid forming. In this study, slurries with varying morphologies of grain for the same alloy with the same fraction solid have tested using a partial filling method. The SEED process was employed, and the pouring temperature adjusted to prepare semi-solid slurries with different grain morphologies. The flow pattern, entrapped air during the filling process, and also microstructure of the samples were examined to characterize the macro and micro flow behavior. The results show that a turbulent macro-flow, leading to entrapped air, and severe segregation appeared in the sample using slurry of T
pour ≥ 660 °C . For the slurry of Tpour < 660 °C, none of the three phenomena found in the sample. This investigation further showed that the detriment of dendrite on the semi-solid forming process, and implied that large size dendrite in semi-solid slurry must avoided.- Published
- 2022
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27. Experimental and Numerical Study of the Effect of Pouring Temperature and Fluid Convection on Spherical Grains Formation
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Qu, Wen Ying, Hu, Xiao Gang, Luo, Min, and Zhu, Qiang
- Abstract
Spherical morphology is the typical characteristic of the microstructure in semi-solid slurries, while the formation mechanism of these spherical grains is still unclear, especially the migration of the solid-liquid interface under different process conditions. This study will focus on the effect of pouring temperature and swirling on the morphology of grains. A phase field-lattice-Boltzmann method using parallel computing and adaptive mesh refinement (Para-AMR) was employed to study the FCC α-Al phase evolution in binary Al-Si aluminum alloy. Study results represent that the pouring temperature has a significant influence on the morphology of the α-Al grains. Low pouring temperature is a benefit for the formation of spherical microstructures. And the swirling can refine the microstructure under high pouring temperature.
- Published
- 2022
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28. Semi-solid processing of aluminum and magnesium alloys: Status, opportunity, and challenge in China
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LI, Gan, QU, Wen-ying, LUO, Min, CHENG, Le, GUO, Chuan, LI, Xing-gang, XU, Zhen, HU, Xiao-gang, LI, Da-quan, LU, Hong-xing, and ZHU, Qiang
- Abstract
Owing to its low cost, short process and low energy consumption, semi-solid processing (SSP) of aluminum (Al) and magnesium (Mg) alloys has been considered as a competitive approach to fabricate complicated components with excellent performance. Over the past decade, significant progress has been achieved in deeply understanding the SSP process, the microstructure and performance of the fabricated components in China. This paper starts with a retrospective overview of some common slurry preparation methods, followed by presenting the performance and the underlying mechanisms of SSP fabricated alloys. Then, the mainstream opinions on the microstructure evolution and rheological flow behavior of semi-solid slurry are discussed. Subsequently, the general situation and some recent examples of industrial applications of SSP are presented. Finally, special attention is paid to the unresolved issues and the future directions in SSP of Al and Mg alloys in China.
- Published
- 2021
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29. UPLC-MS/MS Determination of Chlorogenic Acid, Hyperoside and Astragalin in Plasma and its Pharmacokinetic Application in Liver Injury Rats
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Zhang, Ying, Xu, Shu-ya, Jia, Zhe, Han, Ting, Liu, Meng-nan, Jia, Tian-ying, Qu, Wen-jia, Xu, Xinfang, and Li, Xiang-ri
- Abstract
Background: Cuscutae Semen (CS) is reported to show a hepatoprotective effect. Chlorogenic acid, hyperoside and astragalin are three major biologically active components from CS. Objective: A sensitive method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated to quantify the three components in rat plasma and was successfully used to study pharmacokineticsin liver injury rats. Methods: Plasma samples were prepared with protein precipitation by acetonitrile. Chromatographic separation was achieved on ACQUITY-XBridge BEH C18 column with gradient elution using the mobile phase containing 0.05% formic acid in water (A) and acetonitrile (B). The three components were quantified using Electrospray Ionization (ESI) source in the negative multiple Reaction Monitoring (MRM) mode. Results: Calibration curves of each analyte showed good linearity with correlation coefficients over 0.99. Accuracies (RE%) and precisions (RSD%) were within 15%. The method was stable. Recovery of the target compounds in plasma samples ranged from 87.00% to 102.29%. No matrix effect was found to influence the quantitative method. Conclusion: The UPLC-MS/MS method met the acceptance criteria and was successfully applied to the simultaneous determination of chlorogenic acid, hyperoside and astragalin in rat plasma for the first time. It is suitable for pharmacokinetic application in liver injury rats. It provides the foundation for further development and utilization of the hepatoprotective effect of cuscutae semen.
- Published
- 2021
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30. Surface Effect in a Metastable β Ti-Nb-Sn Alloy
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Qi, Li Chun, Qu, Wen Xiao, Zhu, Yong Qi, and Liu, Qing
- Abstract
The phase compositions of surface and interior in Ti-32Nb-4Sn metastable b alloy were investigated. It was found that this alloy exhibits surface effect significantly different from the effects reported in Ti-10V-2Fe-3Al, Ti-22Nb-9Zr and the other titanium alloys. The surface of Ti-32Nb-4Sn specimen quenched from single b phase region was characterized by dominant b phase and a few of α″ and ω phase. While in the interior of the alloy, a large amount of α² martensite phase was observed in addition to b phase The orientation relationship between the α″ martensite and β phase is (110)
β ∥(002)α″ , (020)β ∥(022)α″ and [001]β ∥[100]α″ .- Published
- 2021
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31. Uplink and Downlink Throughput Optimization Scheme for Millimeter Wave D2D Communication.
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Su, Hui Hui, Qu, Wen Bo, and Peng, Yi
- Subjects
MILLIMETER waves ,TELECOMMUNICATION ,MULTIUSER computer systems ,RESOURCE allocation ,MULTIPLE access protocols (Computer network protocols) - Abstract
The power distribution of terminal direct communication (D2D communication) in 5G communication technology is a hot topic in recent research. In order to improve system capacity and spectrum utilization, this paper combines millimeter wave and D2D communication technology, which is aimed at 28GHz frequency band uplink. The D2D resource allocation in the road and downlink cellular networks is studied, and the total system throughput is maximized to optimize the algorithm. First, the admission set corresponding to each D2D pair is derived. Secondly, considering the power control of each D2D to the user and the cellular user, the throughput in the uplink and downlink is respectively determined. Finally, the D2D is guaranteed. The cellular user channel is assigned to the D2D pair on the premise of maximizing the total throughput. On the surface of the simulation results, the proposed scheme can significantly improve the throughput of the system. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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32. Systematic evaluation during early-phase ischemia predicts outcomes in middle cerebral artery occlusion mice
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Xiao, Xiang-Tian, Luo, Chun, Yuan, Yuan, Xiao, Li, and Qu, Wen-Sheng
- Abstract
Supplemental Digital Content is available in the text.Identifying outcome predictors for ischemic stroke is beneficial for choosing correct intervention protocols. Thus, it is necessary to systemically evaluate histological outcome-associated changes such as hemodynamics, behavior, and body weight during the early phase of ischemia. Here, 50 mice were subjected to 45-min middle cerebral artery occlusion (MCAO) using Longa’s method. Hemodynamic changes were monitored by Doppler laser probe, and behaviors were evaluated by scales while the tissues were visualized by staining. The results by correlation analysis demonstrated that with a probe located near the posterior boundary zone of MCA territory, the latency of anoxic depolarization, as well as the cerebral blood flow reduction during MCAO were confirmed to be predictors for the infarct volume on day 3 post-ischemia; histology showed that the risk of a space-occupying secondary hemorrhage was significantly correlated with the increase of infarct volume versus the traditional Bederson’s neurological deficit scale, a renewed combined behavioral scoring method performed nicely to reflect the severity of tissue lesions. Weight loss was a valuable metric for the enlargement of both infarct volume and secondary hemorrhage. Monitoring changes during early-phase ischemia may benefit the optimization of ischemia models and the discovery of potential intervention targets.See Video Abstract, http:/links.lww.com/WNR/A601).
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- 2021
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33. Design of a test platform with a cyrocooler for InGaAs FPA
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Holland, Andrew D., Beletic, James, Qu, Wen-qing, Chen, Jie, Tang, Qi-Jie, Chen, Jin-ting, Wang, Zhi-yue, Chen, Cheng, Wang, Hui, Zhang, Hong-fei, Li, Tao, Li, Xue, and Wang, Jian
- Published
- 2020
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34. Optimization of microwave heating thickness for spent automobile catalyst
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HE, Guang-jun, LIU, Peng, QU, Wen-wen, WANG, Shi-xing, and ZHANG, Li-bo
- Abstract
A new method was developed to optimize the microwave heating thickness of the spent automobile catalyst in order to improve the uniform distribution of the temperature field. The average penetration depth and the microwave heating thickness of the spent automobile catalyst were calculated by Gauss model and numerical calculation based on dielectric loss tangent and reflection loss. The results showed that the spent automobile catalyst was a medium loss material. The average penetration depth was 1.11 m from room temperature to 800 °C. The optimum microwave heating thickness of the spent automobile catalyst was about 0.83 m or 0.75 times of the average penetration depth. Industrial application analysis indicated that the optimization of heating thickness could improve the uniform distribution of the temperature field and reduce energy consumption.
- Published
- 2020
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35. Using ProCAST to Study the Effects of SEED Process Parameters on the Radial Temperature Distribution in Semi-Solid Slugs
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Luo, Min, Li, Da Quan, Qu, Wen Ying, Midson, Stephen P., Zhu, Qiang, and Fan, Jian Zhong
- Abstract
The SEED (Swirled Enthalpy Equilibrium Device) process was used to produce semi-solid slurries. One of the factors that controls whether or not a slug can be used to produce high quality castings is the solid fraction distribution within the slug, and the solid fraction distribution is strongly dependent upon the temperature distribution. In this study, a model has been developed using ProCAST to investigate the relationship between process parameters and the temperature distribution within slugs. The parameters examined included the heat transfer coefficient between the crucible and slug, the heat transfer coefficient between the crucible and air, the slug diameter, and the initial melt temperature (pouring temperature). It was found that the most important parameters controlling the temperature distribution within slugs were the crucible size and the heat transfer coefficient between crucible and air. Adjustment of other parameters had little influence on the temperature distribution. Processing parameters will be discussed in order to allow the SEED process to be used for the production of large diameter slugs (>100 mm), and for narrow freezing range (0.3<fs<0.5, fs is fraction solid) alloys such as 6063.
- Published
- 2020
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36. Long term spatial-temporal dynamics of fluoride in sources of drinking water and associated health risks in a semiarid region of Northern China.
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Li, Yuan, Wang, Fei, Feng, Jia, Lv, Jun-ping, Liu, Qi, Nan, Fang-ru, Zhang, Wei, Qu, Wen-yan, and Xie, Shu-lian
- Subjects
FLUORIDES ,DRINKING water ,GROUNDWATER ,COAL mining - Abstract
Abstract There is a concern about the increasing prevalence of health problems related to the ingestion of fluoride (F
− ) in the developing world. Drinking water is one important source of F− , and the concentration of F− needs to be known to ensure the safety of drinking water. In this study, F− levels in drinking water were investigated across Taiyuan in Shanxi Province, China. Spatial-temporal distribution characteristics and potential associated health risks were analyzed using GIS. We collected 485 samples from shallow wells without any defluoridation treatments between 2008 and 2016. After analyzing the samples of F− content we found that mean F− levels of urban areas (0.61 ± 0.39 mg L−1 ), suburban areas (0.70 ± 0.87 mg L−1 ) and for all of Taiyuan city (0.63 ± 0.56 mg L−1 ) were in optimum range based on the recommendation by USEPA. However, individual locations within industrial areas (e.g. Gujiao District) had higher F− levels (1.06 mg L−1 ). A concerning result showed that 12.37% of tested locations had F− concentrations larger than 1.0 mg L−1 . We calculated F− Health Risk Indices (HRIs F) and found that highest were associated with suburban areas, especially in the year 2009 and 2010. However, from 2008 to 2016, overall F− levels and HRIs F of the sampled groundwater in Taiyuan City showed a decreasing trend. HRIs F in suburban areas was higher than urban areas, possible due to the heavily prevalent coal mining industry in those areas. Specific policies should be formulated to address HRIs F. Highlights • F- levels of Taiyuan were in optimum range based on the recommendation by USEPA. • Individual locations within industrial areas had higher F- levels. • HRIs F were calculated and the highest associated with suburban areas. • F- levels and HRIs F of the groundwater in Taiyuan showed a decreasing trend. • HRIs F in suburban areas was higher than urban areas. [ABSTRACT FROM AUTHOR]- Published
- 2019
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37. Internal control risk and audit fees: Evidence from China.
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Ji, Xu-dong, Lu, Wei, and Qu, Wen
- Abstract
Abstract This study examines the association between internal control risk and audit fees under the voluntary adopting regime of the Basic Standard of Enterprise Internal Control in China. We find that audit fees are positively related to disclosed internal control weaknesses (ICWs). In particular, they are significantly associated with non-financial reporting-related, but not with financial reporting-related, ICWs. Our results also indicate that voluntary assurance in internal control reports can mitigate higher audit fees associated with ICWs. Our study provides timely evidence relating to the debate on whether the scope of internal control should be expanded to non-financial reporting-related areas. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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38. Clamparene: Synthesis, Structure, and Its Application in Spontaneous Formation of 3D Porous Crystals
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Shi, Bingbing, Jiang, Jingxiong, An, Hui, Qi, Lijuan, Wei, Tai-Bao, Qu, Wen-Juan, and Lin, Qi
- Abstract
Macrocyclic arenes have emerged as pivotal scaffolds in supramolecular chemistry. Despite their significant contributions to molecular recognition and diverse applications, challenges persist in the development of macrocyclic arene-based crystalline materials, particularly in achieving porosity and addressing limitations in adsorption efficiency resulting from the small cavity sizes of existing macrocyclic arenes. In this study, we present the design and synthesis of a novel macrocyclic arene, clamparene (CLP), featuring a rigid backbone, easy synthesis, and a sizable cavity. CLPself-assembles into one-dimensional sub-nanotubes that further organize into a three-dimensional porous framework in the solid state. The crystalline solid of CLPexhibits potential as a porous crystalline adsorbent for various benzene-based contaminants with rapid adsorption kinetics, large uptake amounts, and good recyclability.
- Published
- 2024
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39. Hot Paleocene-Eocene Gangdese arc: Growth of continental crust in southern Tibet.
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Zhou, Li-min, Wang, Rui, Hou, Zeng-qian, Li, Chao, Zhao, Hong, Li, Xin-Wei, and Qu, Wen-Jun
- Abstract
The 1600 km-long Gangdese magmatic belt features extensive Paleocene–Eocene I-type intrusive rocks and coeval volcanic successions, which can be divided into Group I (~69–53 Ma), Group II (~53–49 Ma), and Group III (~49–43 Ma), corresponding to Neo-Tethyan slab rollback, Neo-Tethyan slab breakoff, and ongoing Indian-Asian collision, respectively. The magmas from these three groups show significant variations in geochemical and isotopic compositions, which provide the information of the growth of continental crust in southern Tibet. The most voluminous magmatism in the Gangdese belt occurred during ~53–49 Ma. High zircon saturation temperature (up to 800 °C) and Ti in zircon temperature (up to 980 °C) estimations suggest there is a period of thermal anomaly during ~53–49 Ma. Starting from ~53 Ma, magmas have increased K 2 O contents, and their zircons have decreased Th/U ratios, and Y and Yb contents. Zircons from Group II have the most heterogeneous Hf isotopic compositions (εHf (t) = −5.3 to 15.1). These are evident of ingress of asthenosphere mantle in the arc, extensive crustal melting, and magma mixing. Magma underplating during this time is the main mechanism for the growth of continental crust. With the Indian-Asian collision going on, the magmas in Group III show high Th/Y and La/Yb ratios and K 2 O contents, but significantly low Tzr and T(ti-zr) values (mostly below 750 °C). These features suggest the water-fluxed melting of early arc residues occurred in the late stage of growth of continental crust. The crust has been thickened and nearly mature at this stage. This study has great implication on understanding of growth of continental crust in orogenic belts. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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40. Voluntary corporate social responsibility reporting and financial statement auditing in China.
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Carey, Peter, Liu, Li, and Qu, Wen
- Abstract
This study finds a positive association between voluntary corporate social responsibility (CSR) reporting and audit fees in China. In contrast to prior research from the US, CSR reporting in China is associated with greater earnings management. Results suggest that Chinese firms use CSR reporting as a strategic device for window dressing, and that auditors charge higher fees in response to heightened audit risk and greater audit effort. Further, the positive effects of CSR reporting on audit fees and earnings management are more significant for non-state-owned enterprises (non-SOEs) than for state-owned enterprises, which suggests that non-SOEs have not fully embraced the principles of CSR and essentially use CSR reporting to create the appearance of legitimacy. In additional tests, we find that non-SOEs with more highly rated CSR performance or longer CSR reports are associated with lower audit fees and less earnings management. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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41. Application of the Correlation between Hardness and Strength in Conventional Al Alloys into Semi Solid Processed Products
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Du, Kang, Qu, Wen Ying, Jing, Yan Hong, and Zhu, Qiang
- Abstract
In the field of material production and application, strength and hardness are the two most common properties of metallic materials. It’s one familiar phenomenon that the hardness of one certain alloy has positive relationship with its strength in conventional dendritic alloys. When it comes to non-dendritic semi-solid alloys, it’s unclear that the relationship is still right or not. In this paper, the molecular mechanics, as well as finite element simulation and experimental verification were combined to study the internal deformation regularity of metallic material and the correlation between the two parameters was illustrated. Firstly, the displacement of solid atom in metallic crystal cell was well described in the view of energy cost. Secondly, the total strain amount under local indenting deformation (resistant boundary) and overall impressing deformation (free boundary) were compared to study the correlation between hardness and compression strength in semi-solid globule grain alloy. Finally, the data collected in semi-solid processed products was applied to be compared against traditional casting and wrought aluminum alloys.
- Published
- 2019
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42. Using the Phase Field Method to Investigate Microstructural Evolution of Semi-Solid 357.0 Slurries
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Qu, Wen Ying, Li, Da Quan, Guo, Zhi Peng, Luo, Min, Zhang, Fan, Midson, Stephen P., Hu, Xiao Gang, and Zhang, Yong Zhong
- Abstract
Semi-solid aluminum slurries have globular grains, different from traditional dendritic solidification microstructures. The mechanism responsible for the formation of these globular grains is still in dispute. Some researchers suggest that the globular grains are formed by fractured dendrites, while others report it is due to copious nucleation. This study will model the growth of the α-Al phase during the production of semi-solid slurries using the swirled equilibrium enthalpy device (SEED) process, where liquid alloy with a low superheat is poured into a steel crucible and swirled within the semi-solid region. Experimental observations have shown that the final microstructure of the slurry produced by the SEED process is relatively non-uniform, with large dendrites at surface and fine spherical particles at the center. Open source code for the phase field method has been adopted to simulate the different microstructural evolution for semi-solid alloy 357.0. The effect of localized temperatures under isothermal condition on the morphology of the α-Al particles has been investigated according to the special conditions of the SEED process. In addition, suggestions for modifying the slurry production to achieve more uniform microstructure are discussed.
- Published
- 2019
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43. Effect of Primary α-Al Morphology in Slurry on Segregation during 357 Semi-Solid Die Casting
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Zhang, Hong, Li, Da Quan, Qu, Wen Ying, Zhang, Fan, Luo, Min, Midson, Stephen P., and Zhu, Qiang
- Abstract
Controlling the morphology of the microstructure of the slurry is important during semi-solid die casting. For this project, semi-solid slugs were produced using the SEED (Swirled Enthalpy Equilibrium Device) process, where a fully liquid metal is poured into a steel crucible and cooled into the semi-solid temperature range, and the crucible and slurry are then swirled and cooled to the appropriate temperature (and solid fraction) for semi-solid casting. The pouring temperature of the melt into the crucible during SEED processing has been shown to influence the morphology and size of the aluminum solid particles within the slurry, which can influence the distribution and segregation of the solid particles during die casting. In this study, a specially-designed die with a serpentine-shaped flow channel has been used to study the distribution of the solid particles during semi-solid die casting. The experimental results show that a dendritic structure is formed when the liquid is poured from a high temperature, while a globular semi-solid morphology is more easily formed when poured from a low superheat. The current results also show that a dendritic structure leads to severe segregation during die casting.
- Published
- 2019
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44. Mangiferin prevents corticosterone-induced behavioural deficits via alleviation of oxido-nitrosative stress and down-regulation of indoleamine 2,3-dioxygenase (IDO) activity.
- Author
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Luo, Gao-Quan, Liu, Ling, Gao, Qu-Wen, Wu, Xiao-Na, Xiang, Wei, and Deng, Wen-Ting
- Abstract
Background:In recent years, a substantial amount of experimental studies have demonstrated that exogenous administration of corticosterone causes anxiety and depressive-like behaviour in rodents which involves hypothalamic-pituitary-adrenal axis dysregulation. Our present study aimed to explore the neuroprotective potential of mangiferin against corticosterone-induced anxiety and depressive-like behaviour. Methods:Corticosterone (40 mg/kg; subcutaneously) was administered once daily in swiss albino mice for 21 days. Mice were treated simultaneously with mangiferin (40 mg/kg; p.o.), 30 min prior to the corticosterone injection. Results:Chronic administration of corticosterone caused anxiety and depressive-like behaviour in mice which was significantly alleviated by mangiferin treatment. Biochemical analysis revealed that mangiferin treatment significantly attenuated corticosterone-induced oxido-nitrosative stress and neuroinflammation in the hippocampus region. Furthermore, concomitant treatment with mangiferin significantly enhanced the hippocampal brain-derived neurotrophic factor (BDNF) level and decreased the serum corticosterone level in the corticosterone-treated animals. Western blotting analysis revealed that corticosterone administration significantly up-regulated the indoleamine 2,3-dioxygenase (IDO) protein expression level in the hippocampus which was significantly reduced by mangiferin treatment. Conclusion:Taken together, our results suggest that mangiferin exerts anti-anxiety and antidepressant effect in corticosterone-treated rats, which is probably mediated through up-regulation of BDNF level along with inhibition of oxido-nitrosative stress, neuroinflammation and IDO up-regulation in the hippocampus region. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
45. Design of two ASIC chips for scientific CCD detectors
- Author
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Holland, Andrew D., Beletic, James, Yang, Dong-xu, Gao, Jie, Feng, Yi, Qu, Wen-qing, Wang, Jian-min, Zhang, Hong-fei, and Wang, Jian
- Published
- 2018
- Full Text
- View/download PDF
46. Intrauterine growth retardation-associated syncytin b hypermethylation in maternal rat blood revealed by DNA methylation array analysis
- Author
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Wu, Dong-Mei, Yan, You-E, Ma, Liang-Peng, Liu, Han-Xiao, Qu, Wen, and Ping, Jie
- Abstract
BackgroundEmerging evidence suggests that DNA methylation in maternal blood is a promising target for intrauterine growth retardation (IUGR) screening, a common developmental toxicity. Here, we aimed to screen out IUGR-related DNA methylation status in maternal blood via high-throughput profiling.MethodsPregnant Wistar rats were subcutaneously administered nicotine (1 mg/kg) twice per day from gestational day (GD) 11 to GD20 to establish the IUGR model. MeDIP array assays and the following GO analysis were used to evaluate DNA methylation status in maternal blood. One placental development-associated gene was selected for further confirmation.ResultsGenes regulating the development of multiple organs and major body systems had changed DNA methylation frequencies in the maternal blood of IUGR rats. Placental development, which can affect the development of multiple fetal organs and induce IUGR, is a hypermethylated cluster consisting of four significantly changed genes, including syncytin b (Synb), Lrrc15, Met, and Tex19.1. With the most significant change, Synb hypermethylation in maternal blood was confirmed by bisulfite-sequencing PCR (BSP). Moreover, decreased Synb expression and histological changes were observed in IUGR placentae.ConclusionThe IUGR-associated DNA methylation profile in maternal blood, such as placenta-related Synb hypermethylation, provides evidence for further studies on possible IUGR biomarkers.
- Published
- 2017
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47. A novel cross-modal hashing algorithm based on multimodal deep learning
- Author
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Qu, Wen, Wang, Daling, Feng, Shi, Zhang, Yifei, and Yu, Ge
- Abstract
With the growing popularity of multimodal data on the Web, cross-modal retrieval on large-scale multimedia databases has become an important research topic. Cross-modal retrieval methods based on hashing assume that there is a latent space shared by multimodal features. To model the relationship among heterogeneous data, most existing methods embed the data into a joint abstraction space by linear projections. However, these approaches are sensitive to noise in the data and are unable to make use of unlabeled data and multi-modal data with missing values in real-world applications. To address these challenges, we proposed a novel multimodal deep-learning-based hash (MDLH) algorithm. In particular, MDLH uses a deep neural network to encode heterogeneous features into a compact common representation and learns the hash functions based on the common representation. The parameters of the whole model are fine-tuned in a supervised training stage. Experiments on two standard datasets show that the method achieves more effective results than other methods in cross-modal retrieval. 随着网络上多模态数据的普及, 海量多媒体数据库上的跨模态检索成为研究的热点。跨模态检索方法假设多个模态的数据特征之间存在一个共享的潜在特征空间。因此, 为了建立多模态数据之间的关联, 大部分已有方法通过线性映射将多模态数据分别映射到同一个共享特征空间。但是, 该类方法对于数据中的噪声比较敏感, 并且也无法使用现实场景中的无标记的数据或缺失模态的数据。针对该问题本文提出了一种新的基于多模态深度学习的哈希算法。该方法使用深度神经网络结构将异构特征映射为一个共同的压缩表示, 并在此表示的基础上学习哈希函数。整个模型的参数通过有监督的方式进行训练。在两个标准数据集上的实验结果显示本文的方法能够有效的完成跨模态检索的任务。
- Published
- 2017
- Full Text
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48. Reproductive Toxicity of T Cells in Early Life: Abnormal Immune Development and Postnatal Diseases
- Author
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Liu, Han-xiao, Jiang, Aifang, Chen, Ting, Qu, Wen, Yan, Hui-yi, and Ping, Jie
- Abstract
Immunity is a balanced status with adequate biological defenses to recognize and fight “non-self”, as well as adequate tolerance to recognize “self”. To maintain this immune homeostasis, a well-organized T cell immune network is required, which in part depends on the well-controlled development of alternative effector T cells, with different cytokine repertoires. Recent researches have pointed that developing fetal T cells network is a remarkably sensitive toxicological target for adverse factors in early life. Epidemiological and experimental studies showed an inseparable relationship between T cell developmental toxicity and immune diseases in adults. Considering that the inflammatory and immune disorders have become a growing health problem worldwide, increasing attention is now being paid to the T cell developmental toxicity. We propose that adverse factors may have programming effects on the crucial functions of immune system during early life which is critical for fetal T cell development and the establishment of the distinct T cell repertoires balance. The permanently disturbed intrathymic or peripheral T cell development may in turn lead to the immune disorders in later life. In this manuscript, we reviewed how adverse factors affected T cell development in early-life with the consequence of the immune dysfunction and immune diseases, and further elucidate the mechanisms. These mechanisms will be helpful in prevention and treatment of the increased prevalence of immune diseases by interfering those pathways.
- Published
- 2017
- Full Text
- View/download PDF
49. A highly selective colorimetric and “Off-On” fluorescence sensor for CN−based on Zn(salphenazine) complex
- Author
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Li, Wen-Ting, Qu, Wen-Juan, Zhu, Xin, Li, Qiao, Zhang, Hai-Li, Yao, Hong, Lin, Qi, Zhang, You-Ming, and Wei, Tai-Bao
- Abstract
The development of sensors for selective detection of cyanide ion (CN−) is an important mission to accomplish because of the versatility and toxicity of CN−. In the present work, an “ensemble”-based colorimetric and fluorescent sensor (L2-Zn2+) for CN−ion has been developed. The addition of cyanide ions removed Zn2+from the ensemble (L2-Zn2+) in aqueous medium, resulting in a color change of the solution from red to buff and a “turn-on” fluorescent response. Also, the sensitivity of both the fluorescence- and colorimetric-based assay is below the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. In addition, test strips, which served as convenient and efficient CN−test kits, were fabricated based on the sensor. Notably, the selective detection of cyanide with L2-Zn2+for practical application was also performed in sprouting potatoes.
- Published
- 2017
- Full Text
- View/download PDF
50. A simple method for the formalin fixation of lungs in toxicological pathology studies.
- Author
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Qu, Wen-Sheng, Yin, Ji-Ye, Wang, He-Mei, Dong, Yan-Sheng, and Ding, Ri-Gao
- Subjects
FORMALDEHYDE ,LUNG injury treatment ,PHOTOMICROGRAPHY ,LIGATURE (Surgery) ,AUTOLYSIS ,TOXICOLOGY ,LABORATORY rodents - Abstract
Optimized lung preparation for detailed structural evaluation is required to improve consistency in preclinical safety evaluation, differences of opinion exist among regulatory agency personnel regarding the optimal methods for routine formalin fixation of lungs from rodent toxicology studies. The simple tracheal ligation fixation method emphasizes tracheal ligation before opening the thorax instead of attempting to re-inflate after lung collapse when opening the thorax. Photomicrographs of this method demonstrated an unprecedented ability to maintain the natural lung architecture, in contrast to the unavoidable changes in the alveolar environment by the intratracheal instillation and vascular perfusion methods. In addition, a comparison of fixation methods on lung morphology in a rodent model of LPS-induced acute lung injury demonstrated that the tracheal ligation fixation method may provide a standard approach for morphometry. Additionally, a TUNEL assay was used to determine the degree of autolysis, which revealed that the autolysis was insignificant in the central areas of each lobe of the lung compared to the lung periphery by tracheal ligation fixation. In conclusion, our novel modified method, which avoids the disadvantages of generating artifacts, fulfills the requirement of preserving the clear, natural morphology of the lung making it suitable and worthy of recommendation for toxicological studies in a good laboratory practice (GLP) lab. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
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