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Capsular polysaccharide production from Zunongwangia profunda SM-A87 monitored at single cell level by atomic force microscopy

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DEEP-SEA research PART II-TOPICAL STUDIES IN OCEANOGRAPHY 2018年 155卷 44-49页

作者： Li, Kang Zhao, Long-Sheng Sun, He-Min Tang, Ruo-Cong Chen, Zhi-Hua Su, Hai-Nan Chen, Xiu-Lan Zhang, Yu-Zhong Shandong Univ Inst Marine Sci & Technol State Key Lab Microbial Technol Marine Biotechnol Res Ctr Jinan Shandong Peoples R China Qingdao Natl Lab Marine Sci & Technol Lab Marine Biol & Biotechnol Qingdao Peoples R China

Polysaccharides are secreted by many marine bacteria as a strategy for growth, binding trace metals, adhering to solid surfaces, and to survive adverse conditions. Therefore, they have attracted extensive research interest due to their biological roles as well as potential industrial application. Many works have been carried out to study the growth dynamics of polysaccharides producing bacteria. Average polysaccharide production per cell during growth were usually studied in the past. However, most previous works were carried out at the population level, and the research at a single cell level was rare. Atomic force microscopy (AFM) is a powerful tool in studying single microorganisms and their extracellular polysaccharides. Here we investigated the growth dynamics and capsular polysaccharide (CPS) production of a CPS producing bacterium Zunongwangia profunda SM-A87 isolated from deep-sea sediments with AFM. Z. profunda SM-A87 exhibited slow growth rates at 10 degrees C, which was lower than at optimum growth temperature (30 degrees C). But the CPS production at 10 degrees C was much higher than that at 30 degrees C. Single cell imaging with AFM revealed rod like cell morphology at both temperatures, but filamentous bacteria could sometimes be noticed at 10 degrees C. The CPSs surrounding bacterial cells were observed, and the fibrils of polysaccharides entangled into networks. The diameter of the capsules and the length of the polysaccharides fibrils increased as cultivation time increased. The average volume of the bacterial cells and capsular polysaccharides surrounding each cell at both temperatures were calculated. The average volume of a single bacterial cell was 0.2-0.3 mu m(3), and it increased in exponential phase and slightly decreased in stationary phase, but the average volume of CPS produced by single cells increased during bacterial growth. CPS production increased to 0.097 +/- 0.051 mu m(3) per cell at 10 degrees C in stationary phase, which is larger

关键词： Zunongwangia profunda Capsular polysaccharides Atomic force microscopy Volume

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Response Sensitivity to Design Parameters of RV Reducer

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 115-127页

作者： Yu-Hu Yang Chuan Chen Shi-Yu Wang School of Mechanical Engineering Tianjin University

Dynamic characteristic significantly a ects performance of RV reducer. The current researches mainly pay attention to free vibration properties of RV reducer. In order to satisfy the increasing demand on high performance,response sensi?tivity is analytically studied on the basis of cyclic symmetry structure. Based on the structure characteristics,a dynamic model is developed by taking into account the influence of bearing sti ness,crankshaft bending sti ness and mesh sti ness within planetary and cycloidal stages. For the model,governing equation of motion is derived and solved by Fourier series method. The solution revealed that forced vibrations at primary frequency are well defined structural. There exist three typical forced vibration modes: rotational,translational and planetary component modes. Response sensitivity to basic design parameters is obtained as closed?form expressions by di erential method. With the typical vibration modes,response sensitivity is simplified and classified into three types. Calculation of sensitivity implies that vibrations of the output wheel are sensitive to eccentricity. As eccentricity increases,sensitivity of translation decreases first and then increases,but sensitivity of rotation always increases. The proposed method for analyzing response sensi?tivity provides some principles for selecting parameters for RV reducer from the point of view of forced vibration.

关键词： RV reducer Mesh phasing Vibration modes Sensitivity

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Challenges for third sector organisations in cutback management: a sporting case study of the implications of publicness

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PUBLIC MANAGEMENT REVIEW 2020年第2期22卷 184-205页

作者： Bostock, James Breese, Richard Ridley-Duff, Rory Crowther, Philip Univ Derby Sport Outdoor & Exercise Sci Derby England Sheffield Hallam Univ Sheffield Business Sch Sheffield S Yorkshire England

Cutback management is a key theme for public services in an era of austerity, but the responsibilities for implementing public funding cutbacks do not always fall upon managers employed in the public sector. This article focuses on the cutbacks at third sector organisations (TSOs) - three national governing bodies (NGBs) of sport - which were affected by UK Sport's 'No Compromise' policy following the 2012 Olympics. The article introduces the public funding cutback decision hierarchy as a novel framework which is used alongside existing theory to assess the implications of the severity and immediacy of cutback.

关键词： Sport cutback publicness third sector

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Native promoters of Corynebacterium glutamicum and its application in l-lysine production

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BIOtechNOLOGY LETTERS 2018年第2期40卷 383-391页

作者： Shang, Xiuling Chai, Xin Lu, Xuemei Li, Yuan Zhang, Yun Wang, Guoqiang Zhang, Chen Liu, Shuwen Zhang, Yu Ma, Jiyin Wen, Tingyi Chinese Acad Sci Inst Microbiol CAS Key Lab Pathogen Microbiol & Immunol 1 Beichen West Rd Beijing 100101 Peoples R China Beijing Zhongke EPPEN Biotechnol Co Ltd Beijing 100085 Peoples R China Ningxia EPPEN Biotechnol Co Ltd Ningxia 750100 Peoples R China Univ Chinese Acad Sci Savaid Med Sch Beijing 100049 Peoples R China

To identify useful native promoters of Corynebacterium glutamicum for fine-tuning of gene expression in metabolic engineering. Sixteen native promoters of C. glutamicum were characterized. These promoters covered a strength range of 31-fold with small increments and exhibited relatively stable activity during the whole growth phase using beta-galactosidase as the reporter. The mRNA level and enzymatic activity of the lacZ reporter gene exhibited high correlation (R (2) = 0.96) under the control of these promoters. Sequence analysis found that strong promoters had high similarity of the -10 hexamer to the consensus sequence and preference of the AT-rich UP element upstream the -35 region. To test the utility of the promoter library, the characterized native promoters were applied to modulate the sucCD-encoded succinyl-CoA synthetase expression for l-lysine overproduction. The native promoters with various strengths realize the efficient and precise regulation of gene expression in metabolic engineering of C. glutamicum.

关键词： Corynebacterium glutamicum Gene expression L-Lysine production Metabolic engineering Native promoters Promoters

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A two-chain aspartic protease present in seeds with high affinity for peanut oil bodies

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FOOD CHEMISTRY 2018年 241卷 443-451页

作者： Chen, Yeming Chen, Yajing Zhao, Luping Kong, Xiangzhen Yang, Zhaoqi Hua, Yufei Jiangnan Univ State Key Lab Food Sci & Technol Wuxi Jiangsu Peoples R China Jiangnan Univ Sch Food Sci & Technol Wuxi Jiangsu Peoples R China Jiangnan Univ Sch Pharmaceut Sci Wuxi Jiangsu Peoples R China

Peanut seeds are rich in oil, which exists as oil bodies (OBs). By extraction, peanut crude OBs are obtained and can be used as a food ingredient. In a previous study, it was found that the crude OBs contained an unknown protease, which hydrolyzed the oleosins. This would disrupt the integrity of OBs, and therefore, affect their physical and oxidative stability. In this study, the protein composition of crude OBs and some properties of the unknown protease were examined. The results showed that the protease was a two-chain (32 and 9 kDa) aspartic protease, which showed high affinity for OBs. The optimal pH and temperature for oleosin hydrolysis by the protease were pH 4.0 and 60 degrees C. Interestingly, the aspartic protease not only hydrolyzed OB intrinsic proteins (oleosin, caleosin, and steroleosin), but also extrinsic proteins (especially Ara h 1 allergen and 26-30 kDa arachin).

关键词： Peanut oil bodies Aspartic protease Oleosin Ara h 1 allergen Arachin

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Electro-hydraulic Servo Force Control of Foot Robot Based on Feedback Linearization Sliding Mode Control 13

Electro-hydraulic Servo Force Control of Foot Robot Based on...

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13th World Congress on Intelligent Control and Automation (WCICA)

作者： Huang, Jie An, Honglei Ma, Hongxu Wei, Qing Wang, Jian Natl Univ Def Technol Dept Automat Changsha 410007 Hunan Peoples R China

ISBN: (纸本)9781538673454

considering the perturbation and disturbance of electro-hydraulic servo force control system for foot robot with single joint actuator. Firstly, the dynamic nonlinear model of electro-hydraulic servo actuator is deduced, secondly, the model is locally linearized by using the input/output feedback linearization theory to improve the control accuracy of the nonlinear system. By analyzing the zero dynamic stability of the system, the validity of the linearized model is proved theoretically. Thirdly, the sliding mode variable structure control is designed to compensate the external disturbance and uncertainty, the boundary layer method is added to suppress the high frequency jitter of the system. Finally, the feedback linearized sliding mode control rate of the original nonlinear system is summarized. The comparative simulation experiment between the proposed algorithm and PID are respectively carried out, results show that the algorithm can effectively improve the force tracking control accuracy and achieve a good tracking effect, with a strong robustness to external interference and system parameters perturbation.

关键词： Servomotors Actuators Valves Mathematical model Feedback linearization Force Robots

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The selective catalytic reduction of NO over Ce_(0.3)TiO_x^-supported metal oxide catalysts

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Journal of Environmental Sciences 2018年第3期30卷 1-7页

作者： Zhichen Duan Jian Liu Juan Shi Zhen Zhao Yuechang Wei Xiao Zhang Guiyuan Jiang Aijun Duan State Key Laboratory of Heavy Oil Processing Beijing Key Lab of Oil & Gas Pollution Control China University of Petroleum

A Ce（0.3）TiOxoxide carrier was synthesized via a sol–gel process,and Ce（0.3）TiOxsupported metal（M=Cd,Mn,Fe,W,Mo）oxide catalysts were prepared by the method of incipient-wetness *** catalysts were characterized by means of X-ray diffraction（XRD）,Brunauer–Emmett–Teller（BET）analysis,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,Fourier transform infrared（FT–IR）spectroscopy,UV–Visdiffusereflectancespectroscopy（UV–VisDRS）,and Temperature-programmed reduction with H2（H2-TPR）.The catalytic activities for de-NO（x ）were evaluated by the NH3-SCR *** all the catalysts tested,the 2 wt.%Cd/Ce（0.3）TiOxcatalyst exhibited the best NH3-SCR performance,with a wide temperature window of 250–450℃ for NO conversion above 90%.Moreover,the catalyst showed N2 selectivity greater than 99%from 200 to 450℃.

关键词： NOx NH3-SCR Catalyst Selectivity Ce-Ti oxide

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Excess melanin precursors rescue defective cuticular traits in stony mutant silkworms probably by upregulating four genes encoding RR1-type larval cuticular proteins

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INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020年 119卷 103315页

作者： Qiao, Liang Yan, Zheng-Wen Xiong, Gao Hao, You-jin Wang, Ri-xin Hu, Hai Song, Jiang-bo Tong, Xiao-ling Che, Lin-rong He, Song-zhen Chen, Bin Mallet, James Lu, Cheng Dai, Fang-yin Southwest Univ Coll Biotechnol Minist Agr & Rural Affairs State Key Lab Silkworm Genome BiolKey Lab Sericu Chongqing 400715 Peoples R China Chongqing Normal Univ Inst Entomol & Mol Biol Coll Life Sci Chongqing Key Lab Vector Insects Chongqing 401331 Peoples R China Harvard Univ Dept Organism & Evolutionary Biol Cambridge MA 02138 USA

Melanin and cuticular proteins are vital cuticle components in insects. Cuticular defects caused by mutations in cuticular protein-encoding genes can obstruct melanin deposition. The effects of changes in melanin on the expression of cuticular protein-encoding genes, the cuticular and morphological traits, and the origins of these effects are unknown. We found that the cuticular physical characteristics and the expression patterns of larval cuticular protein-encoding genes markedly differed between the melanic and non-melanic integument regions. By using four p multiple-allele color pattern mutants with increasing degrees of melanism (+(p), p(M), p(S), and p(B)), we found that the degree of melanism and the expression of four RR1-type larval cuticular protein-encoding genes (BmCPR2, BrnLcp18, BmLcp22, and BrnLcp30) were positively correlated. By modulating the content of melanin precursors and the expression of cuticular protein-encoding genes in cells in tissues and in vivo, we showed that this positive correlation was due to the induction of melanin precursors. More importantly, the melanism trait introduced into the BmCPR2 deletion strain Dazao-stony induced up-regulation of three other similar chitin-binding characteristic larval cuticular protein-encoding genes, thus rescuing the cuticular, morphological and adaptability defects of the Dazao-stony strain. This rescue ability increased with increasing melanism levels. This is the first study reporting the induction of cuticular protein-encoding genes by melanin and the biological importance of this induction in affecting the physiological characteristics of the cuticle.

关键词： Melanie coloring Cuticle features Cuticular protein-encoding genes Induction Bombyx mori

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Coupling of Carboxylic Acids with Ynamides and Subsequent Rearrangement for the Synthesis of Imides/Amides

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ORGANIC LETTERS 2018年第17期20卷 5194-5197页

作者： Shen, Yangyong Li, Qi Xu, Gang Cui, Sunliang Zhejiang Univ Coll Chem & Biol Engn Hangzhou 310027 Zhejiang Peoples R China Zhejiang Univ Coll Pharmaceut Sci Inst Drug Discovery & Design Hangzhou 310058 Zhejiang Peoples R China

A coupling of carboxylic acids with ynamides and subsequent rearrangement for the synthesis of imides and amides is reported. The carboxylic acids could couple with ynamides to form alpha-acyloxyenamide followed by sulfonyl group migration and Mumm rearrangement to furnish the amides. Additionally, the products could be subjected to further rearrangement to deliver beta-keto amides. This metal-free process represents an interesting method for chemical bonds cleavage and regeneration. Furthermore, divergent transformation of products were conducted to deliver an array of compounds.

关键词： Organic acids Amides Genetics Chemical reactions Rearrangement

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On Hopping Control for an Articulated Leg of a Quadruped Robot Based on Two-Mass Model 13

On Hopping Control for an Articulated Leg of a Quadruped Rob...

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13th World Congress on Intelligent Control and Automation (WCICA)

作者： Zhang, Zhitong An, Honglei Ma, Hongxu Wei, Qing Wang, Jian Natl Univ Def Technol Dept Automat Changsha 410007 Hunan Peoples R China

ISBN: (纸本)9781538673454

a new hybrid controller for the vertical motion of a two-mass hopping robot is proposed and applied to a triple articulated leg robot of quadruped robots. This work starts by investigating the dynamics of a two-mass model which differs the common-used SLIP model in that the contact forces between the lower leg and the ground is taken into consideration and directly further controlled. This hybrid control strategy mainly consists of three controllers, that is, the leg length controller in flight phase;the direct contact force controller and the simple switch controller in stance phase. Combine the three controllers we can eliminate deviation of the system states trajectory from the desired reference limit cycles. These controllers are then applied on the articulated leg robot by mapping the equivalent actuating force, originally modeled in the two-mass system, into the joint torques based on the dynamics of the proposed legged robot. We conducted several simulations to test the effectiveness of the proposed hybrid controller and the expected hopping motion of the articulated legged robot.

关键词： articulated leg contact force control hopping control limit cycle two-mass mode

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