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Molecular characterization and gene functional analysis of Dicer-2 gene from Nilaparvata lugens （Hemiptera： Geometroidea）

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Insect Science 2013年第1期20卷 61-68页

作者： xiao-yi zhang Kai Lu Jia-Liang Zhou Qiang Zhou State Key Laboratory of Biological Control and Institute of Entomology Sun Yat-sen University Guangzhou China

Nilaparvata lugens （St^il）（Hemiptera： Geometroidea）, a serious rice pest in many countries of Asia, causes a great loss in rice production every year. RNA interference （RNAi） is a powerful technology for gene fimction study in insects and a potential tool for pest control. As a core component of RNAi pathway, Dicer-2 （Dcr-2） protein determines the production of small interfering RNA （siRNA） and is crucial for the efficiency of RNAi. In this study, the full-length complementary DNA （cDNA） ofN. lugens Dcr-2 （NlDcr-2） was first cloned and analyzed, and then the RNAi experiment was conducted to explore the function ofNlDcr-2 gene. The complete Dcv-2 cDNA ofN. lugens was 4 971 bp in length with an open reading frame （ORF） of 1,656 amino acids. Phylogenetic and protein domain analysis showed that the predicted N1Dcr-2 protein was similar to Tribolium castaneum. In the RNAi experiment, the messenger RNA level of NlDcr-2 was significantly reduced by NlDcr-2 double-stranded RNA （dsRNA）（dsDcr-2）. Fifty-five per cent decrease of N1Dcr-2 was found after 4 days of unremitting feeding. No significant effect was observed on the development ofN. lugens after dsRNA ingestion.

关键词： clone Dicer-2 Nilaparvata lugens RNAi qRT-PCR

Palladium-catalyzed amination of chloro-substituted 5-nitropyrimidines with amines

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Chinese Chemical Letters 2017年第3期28卷 583-587页

作者： Meng-Meng Liu Qiong Mei yi-xiao zhang Peng Bai Xiang-Hai Guo Department of Pharmaceutical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300350 China Key Laboratory of Systems Bioengineering (Ministry of Education) Tianjin University Tianfin 300350 China

A concise and efficient approach was developed for the synthesis of mono-substituted and di-substituted pyrimidines products via palladium-catalyzed amination of chloro-substituted 5-nitropyrimidines and amines. This synthetic methodology can produce various di-substituted pyrimidines in high yields with good functional group tolerance, and provide a complementary tool for the syntheses of important intermediates of nucleosides and purines with bioactivities.

关键词： Pd-catalyzed C–N coupling reaction Aryl halide Amines Pyrimidines

Exploring binding mode for styrylquinoline HIV-1 integrase inhibitors using comparative molecular field analysis and docking studies

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Acta Pharmacologica Sinica 2004年第7期25卷 104-112页

作者： xiao-hui MA, xiao-yi zhang, Jian-jun TAN, Wei-zu CHEN, Cun-xin WANG2 College of LifeScience and Bioengineering, Beijing University of Technology, Beijing 100022, China College of Life Science and Bioengineering Beijing University of Technology 北京 100022

AIM: To understand pharmacophore properties of styrylquinoline derivatives and to design inhibitors of HIV-1 integrase. METHODS: Comparative molecular field analysis (CoMFA) was performed to analyze three-dimen- sional quantitative structure-activity relationship (3D-QSAR) of styrylquinoline derivatives. Thirty-eight compounds were randomly divided into a training set of 28 compounds and a test set of 10 compounds. The stability of 3D- QSAR models was proved by the analysis of cross-validated and non-cross-validated methods. Moreover, the binding mode of these compounds and integrase was constructed by AutoDock program. RESULTS: The CoMFA model of the training compounds was reasonably predicted with cross-validated coefficient (q2) and conventional (r2) values (up to 0.696 and 0.754). Then the model was validated by the test set. The resulting CoMFA maps visualized structural requirements for the biological activity of these inhibitors. Docking results showed that a carboxyl group at C-7 and a hydroxyl group at C-8 in the quinoline subunit, bound closely to the divalent metal cofactor (Mg2+) around the integrase catalytic site. Moreover, there is a linear correlation between the binding energy of the inhibitors with integrase and their inhibitory effect. CONCLUSIONS: The present study indicated that the CoMFA model together with docking results could give us helpful hints for drug design as well as interpre- tation of the binding affinity between these inhibitors and integrase.

关键词： HIV integrase inhibitors quinolines comparative molecular field analysis AutoDock

Key Radar Signal Sorting and Recognition Method Based on Clustering Combined with PRI Transform Algorithm

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Journal of Artificial Intelligence and Technology 2022年第2期2卷 62-68页

作者： Kai Kang yi-xiao zhang Wen-pu Guo Luo-geng Tian High-Tech Institute of Xi’an Xi’an710025China Information and Communication College National University of Defense TechnologyXi’an710106China

In this paper,we investigate the problem of key radar signal sorting and recognition in electronic intelligence(ELINT).Our major contribution is the development of a combined approach based on clustering and pulse repetition interval(PRI)transform algorithm,to solve the problem that the traditional methods based on pulse description word(PDW)were not exclusively targeted at tiny particular signals and were less *** achieve this in three steps:firstly,PDW presorting is carried out by the DBSCAN(Density-Based Spatial Clustering of Applications with Noise)clustering algorithm,and then PRI estimates of each cluster are obtained by the PRI transform ***,by judging the matching between various PRI estimates and key targets,it is determined whether the current signal contains key target signals or *** results show that the proposed method should improve the time efficiency of key signal recognition and deal with the complex signal environment with noise interference and overlapping signals.

关键词： DBSCAN clustering PDW PRI transform radar signal recognition

Feasibility and safety of vaginal myomectomy:analysis of 90 cases

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Chinese Medical Journal 2006年第21期119卷 1790-1793页

作者： WEI Feng-hua ZHAO xiao-dong zhang yi Department of Obstetrics and Gynecology Beijing Hospital Beijing 100730 China

Background Vaginal myomectomy was firstly reported in 1994, however, it is a relatively new technique in China. The feasibility and safety of the procedure is still controversial in this country. The aim of this study was to analyze the outcomes of vaginal myomectomy in 90 patients and to investigate the feasibility and safety of the surgery. Methods From June 2001 to June 2004, 90 patients with uterine leiomyoma were treated with vaginal myomectomy in our hospital （vaginal group）. The indications, operative performance, postoperative complications, and recovery of the patients were analyzed and compared with those of 93 patients with uterine leiomyoma treated by laparotomic myomectomy from January 2000 to January 2001 （laparotomy group）. The Student＇s t test was used to compare the continuous variables between the two groups, and the chi-square test was used to compare the categorical variables. The vaginal and laparotomy groups were followed up for 10-34 months （median, 21） and 15-24 months （median, 30）, respectively. Results Vaginal myomectomy was performed successfully in 87 of the 90 patients （96.7%）. In the other 3 patients, the procedure failed and laparotomy was carded out. In both groups, the uterus was enlarged to 8-16 weeks gestational size （median, 10 gestational weeks）. The number of resected tumors was 1 - 12 （median, 2） in the vaginal group and 1-15 （median, 4） in the laparotomy group, respectively （P〉0.05）. The mean operating time, intraoperative blood loss, and postoperative hospital stay were （52± 21） minutes, （230± 44） ml, and （7.0±1.2） days in the vaginal group, and （654±32） minutes, （200±56） ml, and （7.04±1.5） days in the laparotomy group （P〉0.05）. The mean top postoperative temperature was （38.44±1.1）℃ and （37.8±0.6）℃ in the two groups respectively （P〈0.05）. Both groups had one recurrent case during the follow-up （P〉0.05）. Condusions Vaginal myomectomy is feasible and safe in treating uterine leiomyoma. To some extent, it is superior to laparot

关键词： uterine neoplasms leiomyoma surgical procedures, minimally invasive

The sirtuin family in health and disease

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Signal Transduction and Targeted Therapy 2023年第1期8卷 146-219页

作者： Qi-Jun Wu Tie-Ning zhang Huan-Huan Chen Xue-Fei Yu Jia-Le Lv Yu-Yang Liu Ya-Shu Liu Gang Zheng Jun-Qi Zhao yi-Fan Wei Jing-yi Guo Fang-Hua Liu Qing Chang yi-xiao zhang Cai-Gang Liu Yu-Hong Zhao Liaoning Key Laboratory of Precision Medical Research on Major Chronic Disease Shengjing Hospital of China Medical UniversityShenyangChina Department of Clinical Epidemiology Shengjing Hospital of China Medical UniversityShenyangChina Department of Obstetrics and Gynecology Shengjing Hospital of China Medical UniversityShenyangChina Clinical Research Center Shengjing Hospital of China Medical UniversityShenyangChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangChina Department of Oncology Shengjing Hospital of China Medical UniversityShenyangChina Department of Urology Shengjing Hospital of China Medical UniversityShenyangChina Department of Cancer Breast Cancer CenterShengjing Hospital of China Medical UniversityShenyangChina

Sirtuins(SIRTs)are nicotine adenine dinucleotide(+)-dependent histone deacetylases regulating critical signaling pathways in prokaryotes and eukaryotes,and are involved in numerous biological ***,seven mammalian homologs of yeast Sir2 named SIRT1 to SIRT7 have been *** evidence has suggested the vital roles of seven members of the SIRT family in health and disease ***,this protein family plays a variety of important roles in cellular biology such as inflammation,metabolism,oxidative stress,and apoptosis,etc.,thus,it is considered a potential therapeutic target for different kinds of pathologies including cancer,cardiovascular disease,respiratory disease,and other ***,identification of SIRT modulators and exploring the functions of these different modulators have prompted increased efforts to discover new small molecules,which can modify SIRT ***,several randomized controlled trials have indicated that different interventions might affect the expression of SIRT protein in human samples,and supplementation of SIRT modulators might have diverse impact on physiological function in different *** this review,we introduce the history and structure of the SIRT protein family,discuss the molecular mechanisms and biological functions of seven members of the SIRT protein family,elaborate on the regulatory roles of SIRTs in human disease,summarize SIRT inhibitors and activators,and review related clinical studies.

关键词： SIRT1 metabolism inflammation

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半线性波动方程的自相似解

数学学报（中文版） 2005年第6期48卷 1145-1154页

作者：张晓轶中国科学院数学与系统科学研究院北京100080

研究了具有非线性项│u│^αu的半线性波动方程的Cauchy问题，利用仿积分解及交换子估计等技术，证明了当α为一般的实数且满足一定的限制时，Cauchy问题自相似解的存在性．本文的结果回答了Planchon在其工作中所遗留的问题．

关键词：半线性波动方程自相似解仿积分解

Room-temperature polarization and spin switching via electron transfer in a valence tautomer

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Science China Chemistry 2024年

作者： Zhen Liu xiao-yi zhang Zhi-Rui Li Han Xu Hai-Xia Zhao La-Sheng Long Lan-Sun Zheng State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Achieving simultaneous polarization and spin switching at room temperature is essential for advanced multi-state storage and control applications, particularly in magnetoelectrics and electron spintronics, yet such materials are exceedingly rare. Based on polar molecular valence tautomerism of CoⅢ（3,5-DBcat）(3,5-DBsq)（trans-4-stypy）2（1）, room-temperature spin and polarization switching was achieved via electron transfer. Notably, the ferroelectric polarization and spin switching in 1 are modulated by both temperature and light. The successful implementation of room-temperature polarization and spin switching in 1 signifies an important advancement toward practical applications.

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Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie zhang Cancan WU Yuting zhang yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer