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Direct Electrochemical Oxidation of Dihydronicotiamide Adenine Dinucleotide(NADH) at An Ordered Carbon Nanotubes Electrode

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Chinese Chemical Letters 2003年第11期14卷 1171-1174页

作者： Jing CHEN Jian Chun BAO Chen Xin CAI tian Hong LU Department of Chemistry Nanjing Normal UniversityNanjing 210097

An ordered carbon nanotubes (CNTs) film, which was template-synthesized within the porous of an alumina template, modified glassy carbon electrode is fabricated. The electrode exhibits potent electrocatalysis for NADH oxidation in PBS (pH 6.8) with a diminution of the overpotential of more than 600 mV. The anodic peak current increases linearly with NADH concentration from 2?0-5 mol/L to 1?0-3 mol/L with the detection limit of about 5?0-7 mol/L.

关键词： Carbon nanotube ordered carbon nanotube electrode electrocatalysis NADH.

Correlation of microstructure and magnetic properties in Sm(Co_(bal)Fe_(0.1)Cu_(0.1)Zr_(0.033))_(6.93) magnets solution-treated at different temperatures

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Rare Metals 2019年第1期38卷 20-28页

作者： Cheng Xu Hui Wang tian-Li Zhang Alexander Popov Raghavan Gopalan Cheng-Bao Jiang School of Materials Science and Engineering Beihang University M.N. Miheev Institute of Metal Physics Ural Branch of Russian Academy of Sciences International Advanced Research Centre for Powder Metallurgy and New Materials(ARCI) IITM Research Park

The correlation of microstructure and magnetic properties in Sm(Co_(bal)Fe_(0.1)Cu_(0.1)Zr_(0.033))_(6.93) magnets solution-treated at different temperatures was systematically investigated. It is found that the magnets solution-treated at 1219℃ possess a single 1:7 H phase, exhibiting the homogeneous cellular structure during further aging treatment, leading to the optimum magnetic properties. However, for the magnets solution-treated at 1211 and 1223℃,2:17 H or 1:5 H secondary phase will also form besides 1:7 H main phase, which cannot transform into cellular structure,thus deteriorating the magnetic properties greatly. The irreversible magnetization investigations with recoil loops also propose a non-uniform pinning in the magnets induced by the secondary precipitates. At proper solution temperature, Zr is supposed to occupy the Fe-Fe dumbbell sites in the form of Zr-vacancy pairs, leading to the minimum c/a ratio and thus stabilizing the 1:7 H phase. Finally,Sm(Co_(bal)Fe_(0.1)Cu_(0.1)Zr_(0.033))_(6.93) magnets with the maximum energy product and intrinsic coercivity at 550℃ up to 60.73 kJ·m^(-3) and 553.88 kA·m^(-1) were prepared by powder metallurgy method.

关键词： Sm2Co17 Solution treatment Phase constitution Demagnetization curve squareness

Prediction of key transcription factors during skin regeneration by combining gene expression data and regulatory network information analysis

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International Journal of Biomathematics 2019年第3期12卷 23-38页

作者： Ping Huang Peng Ge Qing-Fen tian Guo-Bao Huang Medical Laboratory Diagnostic Center Jinan Central Hospital Affiliated to Shandong University Jinan 250013 Shandong P. R. China Department of Bum and Plastic Surgery The People's Hospital of Zhangqiu Area Jinan 250200 Shandong P. R. China Department of Bum and Plastic Surgery Jinan Central Hospital A ffiliated to Shandong University Jinan 250013 Shandong P. R. China

Burn is one of the most common injuries in clinical practice. The use of transcription factors (TFs) has been reported to reverse the epigenetic rewiring process and has great promise for skin regeneration. To better identify key TFs for skin reprogramming, we proposed a predictive system that conjoint analyzed gene expression data and regulatory network information. Methods: Firstly, the gene expression data in skin tissues were downloaded and the LIMMA package was used to identify differential-expressed genes (DEGs). Then three ways, including identification of TFs from the DEGs, enrichment analysis of TFs by a Fisher’s test, the direct and network-based influence degree analysis of TFs, were used to identify the key TFs related to skin regeneration. Finally, to obtain most comprehensive combination of TFs, the coverage extent of all the TFs were analyzed by Venn diagrams. Results: The top 30 TFs combinations with higher coverage were acquired. Especially, TFAP2A, ZEB1, and NFKB1 exerted greater regulatory influence on other DEGs in the local network and presented relatively higher degrees in the protein–protein interaction (PPI) networks. Conclusion: These TFs identification could give a deeper understanding of the molecular mechanism of cell trans-differentiation, and provide a reference for the skin regeneration and burn treatment.

关键词： Burn regenerative medicine transcription factor biological computational approach influence degree

Theoretical Study of Electronic Structures and Charge Transport Properties of 9,10-Bis（（E）-2-（pyrid-n-yl） vinyl）（n=2, 3, 4） Anthracene

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Chinese Journal of Chemistry 2015年第8期33卷 974-980页

作者： Qing Guo Lijuan Wang Yuanfei Jiang Jing Guo Bin Xu Wenjing tian State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun Jilin 130012 China School of Materials Science and Engineering Harbin Institute of Technology at Weihai Weihai Shandong 264209 China Institution of Atomic and Molecular Physics Jilin University Changchun Jilin 130012 China

Charge carrier mobility is one of the most significant properties for organic semiconductors. In this work, the electronic structures and charge transport properties of 9,10-bis（（E）-2-（pyrid-n-yl）vinyl）（n=2, 3, 4） anthracene （BP2VA, BP3VA and BP4VA） were investigated via the analysis of the molecular geometry, the reorganization en- ergy, the frontier orbital and density of state, as well as the electronic coupling and the charge mobility. The results indicated that the linkage between 9,10-divinyl anthracene unit and pyridine （ortho-, meta- and para-） influenced not only the intra-molecular conformation （i.e., the reorganization energies）, but also the intermolecular interaction （i.e., transfer integrals）, and finally the charge mobility of the molecules. It is also found that：（1） The calculated charge mobilties of holes are dozens of times higher than those of electrons for the three molecules. （2） The charge mobilities of hole and electron of the three molecules display the trend： μBP4VA〉μBPZVA〉μBP3VA, and the hole mobility of BP4VA is as high as as-cm^2/（V·s）.

关键词： charge mobility reorganization energy electronic structure

Resveratrol, an activator of SIRT1, restores erectile function in streptozotocin-induced diabetic rats

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Asian Journal of Andrology 2013年第5期15卷 646-651页

作者： Wen Yu Zan Wan Xue-Feng Qiu Yun Chen Yu-tian Dai Department of Urology Affiliated Drum Tower Hospital School of Medicine Nanjing University Nanjing 210008 China

The high incidence of erectile dysfunction （ED） in diabetes highlights a need for effective treatment strategies. Resveratrol, an activator of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, has received attention for its valuable effects in cancer, neurodegenerative diseases, longevity and cardiovascular disease. To explore the effects of resveratrol in diabetes-induced ED, resveratrol was administered to rats with streptozocin （65 mg kg-1）-induced diabetes. Erectile function, cavernous structure, tissue protein expression of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, p53 and forkhead transcription factor 0 3a （FOXO3a）, superoxide dismutase （SOD） activity and malondialdehyde （MDA） levels in the corpora cavernosa were studied. We found that SIRT1 was expressed in cavernosal tissue, and it was downregulated in the corpora of diabetic rats. The administration of resveratrol upregulated the expression of SI RT1 and restored erectile function. In contrast, resveratrol downregulated the expression of p53 and FOXO3a, which regulate apoptosis and oxidative stress. Furthermore, the resveratrol-treated group showed an improvement in smooth muscle content, SOD activity and MDA levels when compared with the diabetic group. Therefore, the ability of resveratrol to improve diabetes-induced ED is likely related to its activation of SIRT1 expression, thus causing the suppression of apoptosis and resistance towards oxidative stress.

关键词： apoptosis erectile dysfunction oxidative stress resveratrol

Synthesis,Crystal Structure,and Spectral Properties of a Novel Co(II) Complex Containing Imidazole Derivative

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1303-1308页

作者： JIN Feng HAO Fu-Ying MA Ji-Long WU Jie-Ying tian Yu-Peng Department of Chemistry Fuyang Normal College Fuyang 236041 China Department of Chemistry Anhui University Hefei 230039 China State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

A novel imidazole derivative with functional group and π-conjugated system, 1- [trans-4-（4-diethylaminostyryl）phenyl]imidazole （abbreviated as L）, and its Con complex （COCl2L4）2 （Co2C168H184N24Cl4, Mr = 2799.05 ） have been synthesized and the crystal structure of the latter was determined by X-ray diffraction. The crystal is of triclinic, space group PI with a = 8.823（3）, b = 18.799（7）, c =23.065（9） A, α = 77.349（6）, β = 83.128（7）, ）, γ= 80.942（3）°, V = 3671.5（12） A^3, Z = 1, Dc = 1.266 g/cm^3,/z = 0.361 mm^-1 F（000） = 1482, the final R = 0.0587 and wR = 0.1284 for 6562 observed reflections with I 〉 2σ（I）. In the molecular structure of （COCl2L4）2, there are two crystallographically unique units. The Co^Ⅱ atoms are six-coordinated by four N atoms from four imidazole ligands （L） and two Cl atoms to form a distorted octahedral geometry. The optical properties of complex （COCl2L4）2 have been experimentally studied.

关键词： imidazole derivative n-conjugated system Co complex crystal structure optical property

Influence of Chromatogram Baseline Shifts and Exogenous Metabolite Signals on Metabolic Profiles of Traditional Chinese Medicine Chaihu and Its Liver Toxicity Metabonomics

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Chemical Research in Chinese Universities 2017年第1期33卷 17-23页

作者： ZENG Qi FENG Jiangjiang LU tian XU Liangyu MIN Chunyan XIE Hongping College of Pharmaceutical Sciences Soochow University Suzhou 215123 P. R. China Suzhou Institute for Food and Drug Control Suzhou 215104 P. R. China

In an LC-MS investigation of drug metabolic samples from the traditional Chinese medicine Chaihu, the baseline was established via MS selectivity-based chromatogram baseline-shift elimination and exogenous metabolite signals were obtained with MS-based orthogonal projection. Their respective influences on the metabolic chromato- graphic profiles, metabonomics model and evaluation of drug toxicity were investigated. The baseline shift enhanced the difference between the metabolic profiles of the control and Chaihu groups, and the corresponding correlation coefficient decreased from 70.38% to 62.69%. The exogenous metabolite signal led to a biased expression of the evaluated toxicity, and the enhanced expression resulted in an average Mahalanobis distance of approximately 9.4%. Based on established metabonomics models, the results show that Chaihu induces liver toxicity at a lower dose of 25 g/kg, twice a day. At this dose, Chaihu elicits a process of self-repair for its liver toxicity. The signal intensities of exogenous metabolites from Chaihu changed with the administration time, but only the signal intensities of large molecule metabolites（m/z 500--850） from Chaihu had a positive correlation with its toxicity. These results suggest that liver toxicity from low doses of Chaihu was probably caused by the larger molecule components and not by its active components, saikosaponin and flavonoid glycoside.

关键词： Exogenous metabolite signal Chromatograrn baseline shift Metabolic profile Metabonomics Liver to-xicity Chaihu

Performance Analysis of TCP-Reno and TCP-Sack in the Case of a Single Source

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Wuhan University Journal of Natural Sciences 2000年第1期5卷 70-74页

作者： Wang, Xin-miao Yan, Pu-liu Huang, tian-xi Wuhan Univ Wuhan China

This work explores the behavior of both TCP-Reno and TCP-Sack under a simple scenario, where a single TCP source transmits the packets continuously over a single bottleneck node characterized by its queue size, bandwidth and propagation delay. The analysis allows to derive the performance of TCP, the utilization tends to 75% of the bottleneck throughput when the bandwidth×propagation delay pipe becomes very large, while it tends to 100% when the queuing delays are predominant because the queue is never empty. In the transient analysis we show how the initial phase of the session can degrade the performances. These results are proved through simulation.

关键词： Bandwidth Congestion control (communication) Packet networks Telecommunication traffic

An Efficient Encrypted Speech Retrieval Based on Unsupervised Hashing and B+ Tree Dynamic Index

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Computers, Materials & Continua 2023年第7期76卷 107-128页

作者： Qiu-yu Zhang Yu-gui Jia Fang-Peng Li Le-tian Fan School of Computer and Communication Lanzhou University of TechnologyLanzhou730050China

Existing speech retrieval systems are frequently confronted with expanding volumes of speech *** dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval *** study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of *** cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original *** addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted *** B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time *** experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing *** retrieval efficiency is greatly *** to the method of using hash index tables,and the speech data’s security is effectively guaranteed.

关键词： Encrypted speech retrieval unsupervised deep hashing learning to hash B+tree dynamic index DGHV fully homomorphic encryption