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Cloning and characterization of the gene encoding an ubiquitin-activating enzyme E1 domain-containing protein of silkworm, Bombyx moil

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Insect Science 2010年第2期17卷 75-83页

作者： Ping Wu Mu-wang Li Yun-Feng Jiang zi-sheng wang Xi-Jie Guo Sericultural Research Institute Chinese Academy of Agricultural Sciences College of Biotechnology and Environmental Engineering Jiangsu University of Science and Technology Zhenjiang Jiangsu Province China

Bombyx mori cytoplasmic polyhedrosis virus （BmCPV） is one of the major viral pathogens for the silkworm. To date, the molecular mechanism of BmCPV invasion has been unclear. We cloned the full length complementary （c）DNA which encodes the ubiquitin-activating enzyme El-domain containing proteinl （UbE1DC1） ofBombyx mori by using suppression subtraefive hybridization （SSH） and rapid amplification of com- plementary （c）DNA ends （RACE）. The full-length eDNA of UbE1DClgene is 1 919 bp, consisting of a 100 bp 5＇ untranslated region, a 637 bp 3＇ untranslated region and an 1 182 bp open reading frame （ORF）, encoding a 393 amino acid protein. The protein contained the THiF_MoeB_hesA_family domain, an adenosine triphosphate binding site, which belongs to the family of ubiquitin-activating enzyme El. Reverse transcription - polymerase chain reaction analysis from the silkworm tissues, namely silk gland, hemo- cyte, fat body, gonad and midgut revealed that UbE1DC1 was expressed in all the five tissues. The real-time quantitative polymerase chain reaction analysis indicated that the relative expression of UbE1DC1 in the normal midgut was approximately 9.78-fold of that in the BmCPV-infected midgut. It is implicated that UbEIDCI may play an important role in the interaction between the host and BmCPV invasion.

关键词： Bombyx mori Cytoplasmic polyhedrosis virus midgut quantitative real-time PCR rapid amplification of eDNA ends suppression subtractive hybridization

Upper gastrointestinal microbiota and digestive diseases

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World Journal of Gastroenterology 2013年第10期19卷 1541-1550页

作者： zi-Kai wang Yun-sheng Yang Department of Gastroenterology and Hepatology the Chinese PLA General Hospitalthe Chinese PLA Medical Academy

Metagenomics which combines the power of genomics,bioinformatics,and systems biology,provide new access to the microbial *** permit the genetic analysis of complex microbial populations without requiring prior *** the conceptual innovations in metagenomics and the improvements in DNA high-throughput sequencing and bioinformatics analysis technology,gastrointestinal microbiology has entered the metagenomics era and become a hot topic *** microbiome research is underway,however,most studies in this area have focused on the composition and function of the intestinal microbiota and the relationship between intestinal microbiota and metabolic diseases(obesity,diabetes,metabolic syndrome,etc.) and intestinal disorders [inflammatory bowel disease,colorectal cancer,irritable bowel syndrome(IBS),etc.].Few investigations on microbiota have been conducted within the upper gastrointestinal tract(esophagus,stomach and duodenum).The upper gastrointestinal microbiota is essential for several gastrointestinal illnesses,including esophagitis,Barrett's esophagus,and esophageal carcinoma,gastritis and gastric cancer,small intestinal bacterial overgrowth,IBS and celiac ***,the constitution and diversity of the microbiota in different sections of the upper gastrointestinal tract under health and various disease states,as well as the function of microbiota in the pathogenesis of various digestive diseases are still *** current article provides an overview of the recent findings regarding the relationship between upper gastrointestinal microbiota and gastrointestinal diseases;and discusses the study limitations and future directions of upper gastrointestinal microbiota research.

关键词： Microbiota Upper gastrointestinal tract Digestive diseases 16S rDNA Metagenomics

Nanosized As_2O_3/Fe_2O_3 complexes combined with magnetic fluid hyperthermia selectively target liver cancer cells

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World Journal of Gastroenterology 2009年第24期15卷 2995-3002页

作者： zi-Yu wang Jian Song Dong-sheng Zhang School of Clinical Medicine Southeast University Nanjing 210009 China School of Basic Medical Sciences Nanjing University of Traditional Chinese Medicine Naniing 210046 Jiangsu Province. China School of Basic Medical Sciences Southeast University Nanjing 210009 Jiangsu Province China

AIM:To study the methods of preparing the magnetic nano-microspheres of Fe2O3 and As2O3/Fe2O3 complexes and their therapeutic effects with magnetic fluid hyperthermia(MFH). METHODS:Nanospheres were prepared by chemical co-precipitation and their shape and diameter were ***,micronucleus,cell viability,and LD50 along with other in vivo tests were performed to evaluate the Fe2O3 microsphere *** inhibition ratio of tumors after Fe2O3 and As2O3/Fe2O3 injections combined with induced hyperthermia in xenograft human hepatocarcinoma was calculated. RESULTS:Fe2O3 and As2O3/Fe2O3 particles were round with an average diameter of 20 nm and 100 nm as observed under transmission electron *** exposure to an alternating magnetic field(AMF),the temperature of the suspension of magnetic particles increased to 41-51℃,depending on different particle concentrations,and remained stable *** Fe2O3 microspheres are a new kind of biomaterial without cytotoxic *** LD50 of both Fe2O3 and As2O3/Fe2O3 in mice was higher than 5 g/*** to four weeks after Fe2O3 and As2O3/Fe2O3 complex injections into healthy pig livers,no significant differences were found in serum AST,ALT,BUN and Cr levels among thepigs of all groups(P>0.05),and no obvious pathological alterations were *** exposure to alternating magnetic fields,the inhibition ratio of the tumors was significantly different from controls in the Fe2O3 and As2O3/Fe2O3 groups(68.74% and 82.79%,respectively; P<0.01).Tumors of mice in treatment groups showed obvious necrosis,while normal tissues adjoining the tumor and internal organs did not. CONCLUSION:Fe2O3 and As2O3/Fe2O3 complexes exerted radiofrequency-induced hyperthermia and drug toxicity on tumors without any liver or kidney damage. Therefore,nanospheres are ideal carriers for tumortargeted therapy.

关键词： Liver cancer Magnetic fluid hyperthermia Nanoparticle As2O3

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管内智能封堵器通信与控制系统的设计

电子设计工程 2017年第2期25卷 145-149页

作者：陈奕龙梁华庆刘子婧王声辉中国石油大学(北京)地球物理与信息工程学院北京102249 中国石油化工集团中原油田分公司石油工程技术研究院河南濮阳457001

目前国内用于输送石油天然气的管道铺设长度逐年增加,对于油气输送管道的维护维修需求愈发增加。管内智能封堵技术相比传统的封堵技术,在工程量,成本上拥有明显的优势。为了实现管道内工作环境的无线通信控制要求,在管内智能封堵器中,... 详细信息

目前国内用于输送石油天然气的管道铺设长度逐年增加,对于油气输送管道的维护维修需求愈发增加。管内智能封堵技术相比传统的封堵技术,在工程量,成本上拥有明显的优势。为了实现管道内工作环境的无线通信控制要求,在管内智能封堵器中,通信与控制系统是核心技术。本系统采用基于低频电磁波的双向通信方法,地面控制单位发射带有码元信息的低频电磁波,管内作业单元接收到此电磁波,通过滤波、放大、解调得到相应的码元,从而根据码元判断所需要进行的各项操作。并在作业的不同阶段发送代表工作状态的电磁波到地面控制单元。通过建立稳定的双向通信通道,完成地面控制器与管内作业单元的同步工作,完成对管内智能封堵器的控制,保证封堵作业顺利进行。

关键词：智能封堵器无线通信电磁波控制

Tautening effect mechanism of titanium-alloy InterTAN nail

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Rare Metals 2023年第12期42卷 4226-4233页

作者： Xiang-sheng Gao sheng-Kai Ma wang-Ao-Ran Chen Min wang Qi Pan zi-Yu Liu Beijing Key Laboratory of Advanced Manufacturing Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China The Fourth People's Hospital of Jinan Jinan 250031China School of Engineering Medicine Beihang UniversityBeijing 100191China Division of Surgery&Interventional Science University College LondonRoyal National Orthopaedic HospitalLondon HA74LPUK

Although InterTAN(IT)nails are widely employed to treat femoral intertrochanteric fractures,the mechanism behind the tautening effect of titanium-alloy IT nails is not well *** study aimed to reveal the mechanism of this effect.A torque test experiment was conducted,with the torque value recorded and transformed to obtain the tautening ***,theoretical and finite element analyses were performed to further understand the *** influence of age and pitch-difference on the tautening effect was also examined in the study,the results attributed to the pitch-varying integrated interlocking lag *** torque and the corresponding tautening effect drastically increase as the screw is inserted deeper during the second stage,while the torque measured in the first stage is always ***,the tautening force increases with increasing age,this relationship helps evaluate the effect at different *** tautening effect also increases nearly linearly with the pitch difference,which can be adjusted during the IT design stage to select or design IT in engineering practice.

关键词： Tautening effect InterTAN nail Finite element analysis Torque

Dynamic Ring-chain Equilibrium of Nucleophilic Thiol-yne "Click" Polyaddition for Recyclable Poly(dithioacetal)s

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Chinese Journal of Polymer Science 2021年第9期39卷 1146-1154页

作者： Jin-Xia Lei Qi-Yuan wang Fu-sheng Du zi-Chen Li Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Polym.Chem.&Physics of Ministry of EducationDepartment of Polymer Science&EngineeringCollege of Chemistry and Molecular EngineeringCenter for Soft Matter Science and EngineeringPeking UniversityBeijing 100871China

We report a dynamic polymerization system based on the reversible nucleophilic Michael polyaddition of activated alkynes and *** poly(dithioacetal)s(P1-P4)were prepared via the base-catalyzed thiol-yne"click"polyaddition of two dithiols(1,4-butanedithiol(4S)and 1,5-pentanedithiol(5S))and two alkynones(3-butyn-2-one(Y1)and 1-phenyl-2-propyn-1-one(Y2))at high *** systematically investigated the base-catalyzed polymerization of 4S and Y1(for polymer PI)under different conditions,and found that this polymerization was a highly concentration-dependent dynamic system:polymer PI was formed at high concentration,while seven-membered dithioacetal,1-(1,3-dithiepan-2-yl)propan-2-one(C1),was obtained at low *** polymerization of 4S and Y2(for polymer P4)displayed similar polymerization behavior,generating 2-(1,3-dithiepan-2-yl)-1-phenylethanone(C4)at low *** the contrary,polymer P2(from Y1 and 5S)was exclusively obtained with no formation of eight-membered *** polymerizations of Y1 with 1,2-ethanedithiol(2S)and 1,3-dimercaptopropane(3S)only afforded corresponding five-and six-membered dithioacetals,1-(1,3-dithiolan-2-yl)propan-2-one(C2)and 1-(1,3-dithian-2-yl)propan-2-one(C3).This dynamic behavior of PI and P4 was attributed to the concentration-dependent retro-Michael addition reaction between a thiol and a β-sulfido-α,β-unsaturated carbonyl compound catalyzed by ***,polymers P1 and P4 could be depolymerized into Cl and C4 in yields of 58% and 95%,*** ring-opening polymerization of Cl at high concentration could successfully regenerate polymer ***,a new type of closed-loop recyclable poly(dithioacetal)s was developed.

关键词： Poly(dithioacetal)s Nucleophilic thiol-yne"click"polyaddition Chemical recycling Ring-chain equilibrium

Design and motion analysis of reconfigurable wheel-legged mobile robot

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Defence Technology（防务技术） 2022年第6期18卷 1023-1040页

作者： Shuo Zhang Jian-tao Yao Ying-bin wang zi-sheng Liu Yun-dou Xu Yong-sheng Zhao School of Mechanical Engineering Yanshan UniversityHebeiChina

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex *** robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice *** wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a ***,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is *** results showed that the shape conversion can be better realized by increasing the friction factor of the trigger ***,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried *** motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged *** parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ***,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype *** results showed that the surmountable obstacle height of the robot is about3.05 times the spoke *** robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

关键词： Mobile robots Scissor mechanism Kinematics ADAMS simulation Obstacle surmounting

An Enhanced Photoelectric Conversion Efficiency of n-Type Crystalline Silicon p-n Junctions Using a Ferroelectric Passivation Layer

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Chinese Physics Letters 2014年第4期31卷 163-166页

作者： LI zi-Zhen TANG Rong-sheng wang Xiao-Feng ZHENG Fen-Gang Department of Physics and Jiangsu Key Laboratory of Thin Films Soochow University Suzhou 215006 Department of Electronic and Information Engineering Taizhou Polytechnic College Taizhou 225300

A multilayered structure consisting of ferroelectric Pb（Zr, Ti）Oa （PZT） film is deposited by sputtering on the crystalline silicon p-n junction without any buffer layer. The photovoltaic output of the p-n junction is greatly enhanced due to the usage of In2Oa：Sn（ITO）/PZT as top surface passivation layers. The short circuit current and photoelectric conversion emciency of the p-n junction with ITO/PZT ferroelectric films increase about four and six times, respectively, compared with those without any passivation layers. Improvement in the passivated device is mainly attributed to the builtqn feld at the ITO/PZT interface.

关键词： Layer An Enhanced Photoelectric crystalline

Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： zi-Han wang Chun-Hua Huang Zhi-sheng Liu Li Mao Ben-Zhan Zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET