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Analysis and Optimization of a Spatial Parallel Mechanism for a New 5-DOF Hybrid Serial-Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 60-68页

作者： dong-sheng zhang Yun-Dou Xu Jian-Tao Yao Yong-sheng Zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University

Hybrid manipulators have potentially application in machining industries and attract extensive attention from many researchers on the basis of high sti ness and high dexterity. Therefore,in order to expand the application prospects of hybrid manipulator,a novel 5?degree?of?freedom(DOF) hybrid serial?parallel manipulator(HSPM) is proposed. Firstly,the design plan of this manipulator is introduced. Secondly,the analysis of this manipulator is carried out in detail,including kinematics analysis,statics analysis,and workspace analysis. Especially,an amplitude equivalent method of disposing the over?constrained force/couple to the non?overconstrained force/couple is used in the statics analysis. Then,three performance indices are used to optimize the PM. Two of them have been widely used,and the third one is a new index which considers the characteristics of the actuated force. Based on the performance indices,the performance atlas is drawn and the optimal design of the PM is investigated. In order to satisfy the anticipant kinetic characteristics of the PM,the verification of the optimized physical dimension is done and the workspace based on the optimized physical dimension is carried out. This paper will lay good theoretical foundations for application of this novel HSPM and also can be applied to other hybrid manipulators.

关键词： Parallel mechanism Performance indices Optimal design Performance atlas

Bacterial and archaeal communities in the surface sediment from the northern slope of the South China Sea

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第12期10卷 890-901页

作者： Li LIAO Xue-wei XU Chun-sheng WANG dong-sheng zhang Min WU College of Life Sciences Zhejiang University Hangzhou 310058 China Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration Hangzhou 310012 China The Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

Microbial diversity of sediments from the northern slope of the South China Sea was studied by constructing bacterial and archaeal 16S rRNA gene clone libraries. Fourteen bacterial phylogenetic groups were detected, including Gammaproteobacteria, Deltaproteobacteria, Planctomycetes, Alphaproteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Chloroflexi, Acidobacteria, Betaproteobacteria, Nitrospirae, candidate divisions OP8 and OP 11, and an unknown group. Gammaproteobacteria was the predominant group in bacterial libraries with the percentage ranging from 31.8% to 63.2%. However, archaeal libraries had relatively lower diversity, with most clones belonging to marine archaeal group I uncultured Crenarehaeota. In addition, two novel euryarchaeal clones were detected not to match any culture-dependent or -independent isolates. Compared with other gas hydrate-rich ecosystems and different areas of the South China Sea, a distinct microbial community was revealed in this study.

关键词： 16S rRNA Library Diversitv South China Sea

Circular RNA circNCOA3 promotes tumor progression and anti-PD-1 resistance in colorectal cancer

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Cancer Drug Resistance 2024年第1期7卷 925-939页

作者： dong-Liang Chen Nuo Chen Hui sheng dong-sheng zhang State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060GuangdongChina

Aim:Circular RNAs(circRNAs)have been found to be involved in tumor progression,but their role in colorectal cancer(CRC)immune escape remains to be ***:circRNAs differentially expressed in responsive and resistant CRC tissues to programmed cell death 1(PD-1)antibody therapy were identified by microarray *** clinical and pathological significance of circNCOA3 was validated in a separate cohort of CRC *** function of circNCOA3 was explored *** immunoprecipitation and luciferase activity assays were conducted to identify downstream targets of ***:The circNCOA3 was markedly overexpressed in CRC samples resistant to PD-1 ***3 expression was significantly correlated with adverse tumor phenotypes and poor outcomes in CRC *** of circNCOA3 expression markedly suppressed the proliferative and invasive capability of CRC ***,knockdown of circNCOA3 increased the proportion of CD8+T cells while decreasing the proportion of myeloid-derived suppressor cells(MDSCs).Knockdown of circNCOA3 inhibited tumor growth and increased the sensitivity to PD-1 antibody treatment in mouse tumor *** studies revealed that circNCOA3 acted as a competing endogenous RNA(ceRNA)for miR-203a-3p.1 to influence the level of ***:Our findings indicate that circNCOA3 might be useful as a potential biomarker to predict the efficacy and prognosis of CRC patients treated with anti-PD-1 therapy.

关键词： circRNA circNCOA3 colorectal cancer anti-PD-1 therapy immune evasion

Evaluation of Breeding Programs Combining Genomic Information in Chinese Holstein

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Agricultural Sciences in China 2011年第12期10卷 1949-1957页

作者： CHEN Jun WANG Ya-chun zhang Yi SUN dong-xiao zhang sheng-li zhang Yuan College of Animal Science and Technology/National Engineering Laboratory for Animal Breeding/Key Laboratory of Agricultural Animal Genetics and Breeding China Agricultural University Beijing 100193 P.R.China

Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing program （PT） and young sire program （YS） were compared with breeding program using genomic selection （GS） taking parameters derived from Chinese Holstein breeding system. The results showed that, GS shortened generation interval by 1.5-2.2 years, and increased the genetic progress by 30-50%, comparing to PT and YS, respectively. Economic analysis showed that GS could obtain a higher breeding efficiency, being 119 and 97% higher than that of PT and YS, respectively; and GS was also powerful in improving functional traits with a low heritability. Main factors affecting breeding efficiency in GS were further discussed, including selection intensity, accuracy and the cost of SNP genotyping. Our finding provided references for future designing and implementing GS in Chinese dairy population.

关键词： Chinese Holstein genomic selection progeny-testing program young sire program breeding plan

Expression Analysis of Dihydroflavonol 4-Reductase Genes Involved in Anthocyanin Biosynthesis in Purple Grains of Wheat

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Journal of Integrative Plant Biology 2005年第9期47卷 1107-1114页

作者： Mao-Sen LIU Fang WANG Yu-Xiu dong Xian-sheng zhang Shandong Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Taian Shandong 271018 China

The grain color of wheat （Triticum aestivum L.） is an important characteristic in crop production. Dihydroflavonol 4-reductase genes （DFR） encode the key enzyme dihydroflavonol 4-reductase, which is involved in the pigmentation of plant tissues. To investigate the molecular mechanism of anthocyanin deposition in grains of wheat, we determined the expression of the wheat DFR gene in purple grains of cultivar Heimai 76. The results showed that DFR transcripts were localized in the seed coat of purple grains rather than in the pericarp, whereas anthocyanins were accumulated in both tissues of purple grains, suggesting that anthocyanin deposition was mainly regulated at the transcriptional level. Overexpression of the TaDFR-A gene in Arabidopsis showed that TaDFR-A was responsible for the pigmentation of Arabidopsis plant tissues, indicating TaDFR-A gene has the same role in Arabidopsis.

关键词： anthocyanin dihydroflavonol 4-reductase localization of TaDFR transcripts purple grain wheat.

Diagnostic value of different color ultrasound diagnostic method in endometrial lesions

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World Journal of Clinical Cases 2021年第19期9卷 5037-5045页

作者： Xiao-Lin Lin dong-sheng zhang Zhi-Ye Ju Xiu-Ming Li Yao-Zhu zhang Department of Ultrasound Pingyi County Traditional Chinese Medicine HospitalLinyi 273300Shandong ProvinceChina Department of Ultrasound Rizhao Peoples HospitalRizhao 276800Shandong ProvinceChina Department of Gastroenterology Pingyi County Traditional Chinese Medicine HospitalLinyi 273300Shandong ProvinceChina

BACKGROUND Endometrial lesions include endometrial cancer and inferior *** them,endometrial cancer as a malignant tumor seriously endangers the life and health of *** is an important means of diagnosing female reproductive system diseases,and it is of critical value for the early diagnosis of endometrial ***,different ultrasound inspection programs have achieved different *** is of great significance to choose a suitable inspection *** To explore the diagnostic efficacy of different ultrasonic examination methods in clinical endometrial *** The 140 patients with endometrial lesions who were treated in our hospital from April 2018 to October 2019 were used as the research *** patients underwent transvaginal color ultrasound and transabdominal color *** compared the diagnostic coincidence and image display effects of the two different examination methods,and the endometrial thickness,blood flow,uterine effusion and resistance index of different diseases were observed by transvaginal color *** The diagnostic coincidence rate of all types of diseases of transvaginal color ultrasound was significantly higher than that of transabdominal color ultrasound(P=0.001,0.005,0.001 and 0.001).In addition,the excellent and good rate of image display of transvaginal color ultrasound was higher than that of transabdominal color ultrasound(P=0.001).There were significant differences in endometrial thickness in patients with different types of endometrial lesions through the transvaginal color examination(P=0.001).The incidence rate of uterine effusion in patients with endometrial carcinoma was significantly higher than that in patients with other types of endometrial lesions(P=0.001),and the rate of the blood flow was the highest(P=0.001).The comparison of blood flow resistance index indicated that the blood flow resistance index in endometrial cancer patients was the lowest,which s

关键词： Endometrial lesions Transvaginal color ultrasound Transabdominal color ultrasound Diagnostic conformity Blood flow Resistance index

Fully differential optoelectronic integrated receiver implemented by 0.35μm standard CMOS process

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Optoelectronics Letters 2008年第6期4卷 395-398页

作者： YU Chang-liang MAO Lu-hong XIAO Xin-dong XIE sheng zhang Shi-lin School of Electronic Information Engineering Tianjin University Tianjin 300072 China

A high-bandwidth, high-sensitivity fully differential optoelectronic integrated receiver is implemented in a chartered 3.3 V standard 0.35μm analbg CMOS process. To convert the incident light into a pair of fully differential photo-currents, a novel fully differential photodetector is proposed, which is composed of two completely identical photodiodes. The mea- surement results show that the receiver achieves a 1.11 GHz 3 dB bandwidth and a -13 dBm sensitivity for a 10-12 bit error at 1.5 Gb/s data rate under illumination by 850 nm incident lights.

关键词：光电子联合接收器 CMOS 高灵敏度光电二极管

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

Adjuvant chemotherapy,p53,carcinoembryonic antigen expression and prognosis after D2 gastrectomy for gastric adenocarcinoma

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World Journal of Gastroenterology 2014年第1期20卷 264-273页

作者： Ming-Ming He dong-sheng zhang Feng Wang Zhi-Qiang Wang Hui-Yan Luo Chao Ren Ying Jin dong-Liang Chen Rui-Hua Xu State Key Laboratory of Oncology in South China Department of Medical OncologySun Yat-sen University Cancer Center

AIM: To investigate adjuvant chemotherapy, p53 and carcinoembryonic antigen (CEA) expression and prognosis after D2 gastrectomy for stage II/III gastric adenocarcinoma.

关键词： Gastric adenocarcinoma Adjuvant chemotherapy p53 Carcinoembryonic antigen Immunohistochemistry