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Design and synthesis of chiral single-armed molecular tweezers derived fromα-hyodeoxycholic acid

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Chinese Chemical Letters 2009年第3期20卷 265-268页

作者： Jian Wang xiao ya yuan Jin Yue Wang Shu Hua Che Department of Chemistry and Chemical Engineering Yibin University Yibin 644007 China College of Science Chongqing Jiaotong University Chongqing 400074 China College of Chemistry Sichuan University Chengdu 610064 China

A novel type of molecular tweezers with different chiral center and cleft has been designed and prepared by using α- hyodeoxycholic acid as spacer and D/L-amino acid methyl ester as chiral arm attached at 3-position. Their structures were elucidated by ^1H NMR, FTIR and elemental analysis. Their recognition properties for various D/L-amino acid methyl esters were also investigated. The preliminary results indicated that these chiral single-armed molecular tweezers exhibited good recognition ability for D/L-amino acid methyl esters with high association constant （up to 5.24 × 10^3 L mol^-1）.

关键词： α-Hyodeoxycholic acid Molecular tweezers Synthesis Recognition

Immobilizing BINOL via Suzuki Reaction:Synthesis and Application in Catalytic Asymmetric Oxidation of Sulfide to Sulfoxide

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Chinese Chemical Letters 2006年第7期17卷 911-912页

作者： xiao ya yuan Hai yan LI Zheng Pu ZHANG P. HODGE Key Laboratory of Functional Polymer Materials Ministry of Education Nankai University Institute of Polymer Chemistry Nankai University Tianjin 300071 Chemistry Department Manchester University M13 9PL U.K

Immobilizing chiral 1,1＇-bi-2-naphthol （BINOL） in one step onto polymer backbone via stable carbon-carbon bond through Suzuki reaction was achieved. The application of this immobilized chiral BINOL to the catalytic asymmetric oxidation of sulfide to sulfoxide exhibited good activity （up to 60% yield） and high enantioselectivity （up to 89% ee）. The immobilized chiral catalyst was very stable and could be readily reused for over 5 times without significant loss of catalytic activity and enantioselectivity.

关键词： 1,1'-Bi-2-naphthol asymmetric catalysis immobilization sulfoxide.

Research on feed-pulse collaborative control method in micro-electrical discharge machining

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Advances in Manufacturing 2024年第2期12卷 270-287页

作者： Qiang Gao ya-Ou Zhang Xue-Cheng Xi yuan-Ding Wang xiao-Fei Chen Wan-Sheng Zhao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China State Key Laboratory of Mechanical System and Vibration Shanghai200240People’s Republic of China Shanghai Institute of Space Propulsion Shanghai201112People’s Republic of China

Reducing the short-circuit rate and increasing the effective discharge rate are important targets for improving the servo control effect of micro-electrical discharge machining(micro-EDM),as these two indicators are closely related to the machining efficiency and *** this study,a feed-pulse collaborative control(FPCC)method is proposed for micro-EDM based on two dimensions(space and time).In the spatial dimension,a feed control strategy with a discharge holding process is ***,in the time dimension,a forward-looking pulse control strategy is adopted,in which the pulse interval is adjusted based on a sequence analysis of feed commands and discharge *** experiments are carried out to determine the key parameters used in this method,including the discharge holding threshold and pulse interval adjustment value(T_(off_(adj))).The feed smoothness and discharge sufficiency analyses of the experimental results show that compared to the traditional double threshold average voltage method,the FPCC method reduces the number of long-distance retreats by 64%and improves the effective discharge time by 40%.

关键词： Micro-electrical discharge machining(micro-EDM) Electrode feed control Discharge pulse control Machining surface quality

Realizing quantum imaginary time evolution in experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 167-168页

作者： xiao yuan Center on Frontiers of Computing Studies Peking UniversityBeijing 100871China School of Computer Science Peking UniversityBeijing 100871China

NISQ,or Noisy Intermediate-Scale Quantum computing,represents a pivotal and the state-of-the-art quantum technology[1].Characterized by intermediate-scale quantum devices that are beyond classical computational capabilities yet fall short of the error-correction thresholds required for fault-tolerant quantum computing,NISQ devices exhibit both promise and *** devices hold immense potential in solving certain computational problems that surpass classical capabilities,with wide applications in optimization,machine learning,and quantum chemistry.

关键词： quantum imaginary correction

Molecular Cloning and Characterization of cDNA Encoding Fibrinolytic Enzyme-3 from Earthworm Eisenia foetida

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 303-308页

作者： Guo-Qing DONG, xiao-Ling yuan, ya-Jun SHAN, Zhen-Hu ZHAO, Jia-Pei CHEN, and Yu-Wen CONG* Department of Experimental Therapy of ARS, Beijing Institute of Radiation Medicine, Beijing 100850, China Department of Experimental Therapy of ARS Beijing Institute of Radiation MedicineBeijing 100850 China

The earthworm fibrinolytic enzyme-3 (EFE-3, GenBank accession No: AY438622), from the earthworm Eisenia foetida, is a component of earthworm fibrinolytic enzymes. In this study, cDNA encoding the EFE-3 was cloned by RT-PCR. The cDNA contained an open reading frame of 741 nucleotides, which encoded a deduced protein of 247 amino acid residues, including signal sequences. EFE-3 showed a high degree of homology to earthworm (Lumbricus rebullus) proteases F-III-1, F-III-2, and bovine trypsin. The recombinant EFE-3 was expressed in E. coli as inclusion bodies, and the gene encoding the native form of EFE-3 was expressed in COS-7 cells in the medium. Both the refolding product of inclusion bodies and the secreted protease could dissolve the artificial fibrin plate.

关键词： earthworm Eisenia foetida earthworm fibrinolytic enzyme cloning expression refolding

Mechanism of high-energy pulsed current-assisted rolling of 08AL carbon steel ultra-thin strip

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Journal of Iron and Steel Research International 2024年第2期31卷 416-427页

作者： Zhong-kai Ren ya-nan Xu Jia-zhao Chen He Li Rui-lin yuan Zhen-hua Wang Tao Wang xiao Liu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710016ShaanxiChina

To improve the plastic deformation performance of a 08AL carbon steel ultra-thin strip,a pulsed electric field was integrated into the plastic processing of the ultra-thin strip,and the effects of high-energy current on its deformation ability were ***-assisted tensile tests were employed,and the results clarified that the pulsed current could reduce the activation energy of faults and promoted dislocation slip within grains and at grain boundaries,leading to a decrease in the deformation resistance of the metal and an increase in its plastic *** the current density of 2.0 A/mm2,the yield strength,tensile strength,and elongation of the rolled sample reached 425 MPa,467 MPa,and 12.5%,*** the rolling process,it was found that the pulsed current promoted the dynamic recrystallization of the ultra-thin strip,reduced its dislocation density and deformation resistance,and promoted the coordinated deformation of the metal.

关键词： 08AL ultra-thin strip High-energy pulsed current Mechanical property Dislocation density Dynamic recrystallization

A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT

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Computers, Materials & Continua 2024年第2期78卷 1881-1895页

作者： xiao Feng Zheng yuan Cyber Security Academy Beijing University of Posts and TelecommunicationsBeijing100876China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China State Grid Info-Telecom Great Power Science and Technology Co. Ltd.Beijing102211China

First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction *** weight the time attenuation factor to each historical interaction record for updating and got the new historical record *** refer to the beta distribution to enhance the flexibility and adaptability of the direct trust assessment model to better capture time trends in the historical *** we propose an autoencoder-based trust clustering *** perform feature extraction based on *** leibler(KL)divergence is used to calculate the reconstruction *** constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency and introduce sparse constraints into the hidden layer of the *** sparse penalty term in the loss function measures the difference through the KL *** clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering *** the clustering process,edge nodes have a variety of trustworthy attribute *** assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of ***,we introduced adaptive weights to calculate comprehensive trust *** experiments prove that our trust evaluation mechanism has excellent reliability and accuracy.

关键词： Cross-domain authentication trust evaluation autoencoder

UPLC-Q-TOF/MS-Based Serum Metabolomics Reveals Potential Anti-tumor Mechanism of Banxia Xiexin Decoction in Colorectal Cancer Mice

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Chinese Journal of Integrative Medicine 2024年第7期30卷 623-632页

作者： YUE Yin-zi LI Ming-xuan WANG xiao-hui QIN yuan-yuan WANG ya-hui TAN Jin-hua SU Lian-lin yaN Shuai Department of General Surgery Suzhou TCM Hospital Affiliated to Nanjing University of Chinese MedicineSuzhou215009China School of Pharmacy Nanjing University of Chinese MedicineNanjing210023China Department of General Surgery Bayinguoleng Mongolian Autonomous Prefecture People’s HospitalXinjiang Uygur Autonomous RegionKorla841000China Department of Pharmacy Suzhou TCM Hospital Affiliated to Nanjing University of Chinese MedicineSuzhou215009China Department of Anorectal Surgery Suzhou TCM Hospital Affiliated to Nanjing University of Chinese MedicineSuzhou215009China

Objective To clarify the potential mechanism of Banxia Xiexin Decoction(BXD)on colorectal cancer(CRC)from the perspective of *** Forty male C57BL/6 mice were randomly divided into normal control(NC),azoxymethane/dextran sulfate sodium(AOM/DSS)model,low-dose BXD(L-BXD),high-dose BXD(H-BXD)and mesalamine(MS)groups according to a random number table,8 mice in each *** cancer model was induced by AOM/*** was administered daily at doses of 3.915(L-BXD)and 15.66 g/kg(H-BXD)by gavage for consecutive 21 days,and 100 mg/kg MS was used as positive *** the entire modeling cycle,colon length of mice was measured and quantity of colorectal tumors were *** spleen and thymus index were determined by calculating the spleen/thymus weight to body *** cytokine and changes of serum metabolites were analyzed by enzyme-linked immunosorbent assay kits and ultra performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q/TOF-MS),*** Notably,BXD supplementation protected against weight loss,mitigated tumor formation,and diminished histologic damage in mice treated with AOM/DSS(P<0.05 or P<0.01).Moreover,BXD suppressed expression of serum inflammatory enzymes,and improved the spleen and thymus index(P<0.05).Compared with the normal group,102 kinds of differential metabolites were screened in the AOM/DSS group,including 48 potential biomarkers,involving 18 main metabolic *** 18 potential biomarkers related to CRC were identified,and the anti-CRC mechanism of BXD was closely related to D-glutamine and D-glutamate metabolism,phenylalanine,tyrosine and tryptophan biosynthesis,arginine biosynthesis,nitrogen metabolism and so *** BXD exerts partial protective effects on AOM/DSS-induced CRC by reducing inflammation,protecting organism immunity ability,and regulating amino acid metabolism.

关键词： colorectal cancer metabolomics ultra performance liquid chromatography-quadrupole/time-of-flight mass spectrometry azoxymethane dextran sulfate sodium Banxia Xiexin Decoction Chinese medicine

Integrated multi-omics analysis reveals liver metabolic reprogramming by fish iridovirus and antiviral function of alpha-linolenic acid

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Zoological Research 2024年第3期45卷 520-534页

作者： Lin Liu ya Zhang Meng-Di yuan Dong-Miao xiao Wei-Hua Xu Qi Zheng Qi-Wei Qin You-Hua Huang xiao-Hong Huang College of Marine Sciences South China Agricultural UniversityGuangdong Laboratory for Lingnan Modern AgricultureGuangzhouGuangdong 510642China Nansha-South China Agricultural University Fishery Research Institute GuangzhouGuangdong 511464China Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiGuangdong 519082China

Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate;however,the molecular mechanisms underpinning its pathogenesis are not well ***,a multi-omics approach was applied to groupers infected with Singapore grouper iridovirus(SGIV),focusing on the roles of key *** showed that SGIV induced obvious histopathological damage and changes in metabolic enzymes within the ***,SGIV significantly reduced the contents of lipid droplets,triglycerides,cholesterol,and *** analysis indicated that the altered metabolites were enriched in 19 pathways,with a notable down-regulation of lipid metabolites such as glycerophosphates and alpha-linolenic acid(ALA),consistent with disturbed lipid homeostasis in the *** of transcriptomic and metabolomic data revealed that the top enriched pathways were related to cell growth and death and nucleotide,carbohydrate,amino acid,and lipid metabolism,supporting the conclusion that SGIV infection induced liver metabolic *** integrative transcriptomic and proteomic analysis indicated that SGIV infection activated crucial molecular events in a phagosome-immune depression-metabolism dysregulation-necrosis signaling *** note,integrative multi-omics analysis demonstrated the consumption of ALA and linoleic acid(LA)metabolites,and the accumulation of L-glutamic acid(GA),accompanied by alterations in immune,inflammation,and cell death-related *** experimental data showed that ALA,but not GA,suppressed SGIV replication by activating antioxidant and anti-inflammatory responses in the ***,these findings provide a comprehensive resource for understanding host response dynamics during fish iridovirus infection and highlight the antiviral potential of ALA in the prevention and treatment of iridoviral diseases.

关键词： Iridovirus Liver damage Metabolic reprogramming SGIV Alpha-linolenic acid Antiinflammatory