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Identifying Chinese species of Gammarus(Crustacea:Amphipoda) using DNA barcoding

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Current Zoology 2009年第2期55卷 158-164页

作者： zhong-e hou Zhu LI Shu-qiang LI Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Beijing Museum of Natural History Beijing 100050 China

Using a standard cytochrome c oxidase I sequence,DNA barcoding has been shown to be effective to distinguish known species and to discover cryptic species. Here we assessed the efficiency of DNA barcoding for the amphipod genus Gammarus from China. The maximum intraspecific divergence for widespread species,Gammarus lacustris,was 3.5%,and mean interspecific divergence reached 21.9%. We presented a conservative benchmark for determining provisional species using maximum intraspecific divergence of Gammarus lacustris. Thirty-one species possessed distinct barcode clusters. Two species were comprised of highly divergent clades with strong neighbor-joining bootstrap values,and likely indicated the presence of cryptic species. Although DNA barcoding is effective,future identification of species of Gammarus should incorporate DNA barcoding and morphological detection.

关键词： Gammarus Cytochrome c oxidase I DNA barcoding Cryptic species Taxonomy

Folding of Tubular Waterbomb

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Research 2020年第1期2020卷 158-165页

作者： Jiayao Ma Huijuan Feng Yan Chen Degao hou zhong You Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University135 Yaguan RoadTianjin 300350China School of Mechanical Engineering Tianjin University135 Yaguan RoadTianjin 300350China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK

Origami has recently emerged as a promising building block of mechanical metamaterials because it offers a purely geometric design approach independent of scale and constituent *** folding mechanics of origami-inspired metamaterials,i.e.,whether the deformation involves only rotation of crease lines(rigid origami)or both crease rotation and facet distortion(nonrigid origami),is critical for fine-tuning their mechanical properties yet very difficult to determine for origami patterns with complex ***,we characterize the folding of tubular waterbomb using a combined kinematic and structural *** for the first time uncover that a waterbomb tube can undergo a mixed mode involving both rigid origami motion and nonrigid structural deformation,and the transition between them can lead to a substantial change in the ***,we derive theoretically the range of geometric parameters for the transition to occur,which paves the road to program the mechanical properties of the waterbomb *** expect that such analysis and design approach will be applicable to more general origami patterns to create innovative programmable metamaterials,serving for a wide range of applications including aerospace systems,soft robotics,morphing structures,and medical devices.

关键词： deformation rotation rigid

Genome-wide analysis of the synonymous codon usage patterns in apple

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Journal of Integrative Agriculture 2016年第5期15卷 983-991页

作者： LI Ning SUN Mei-hong JIANG Ze-sheng SHU huai-rui ZHANG Shi-zhong State Key Laboratory of Crop Biology Shandong Agricultural University

Apple（Malus×domestica） has been proposed as an important woody plant and the major cultivated fruit trees in temperate regions. Apple whole genome sequencing has been completed, which provided an excellent opportunity for genome-wide analysis of the synonymous codon usage patterns. In this study, a multivariate bioinformatics analysis was performed to reveal the characteristics of synonymous codon usage and the main factors affecting codon bias in apple. The neutrality, correspondence, and correlation analyses were performed by Codon W and SPSS（Statistical Product and Service Solutions） programs, indicating that the apple genome codon usage patterns were affected by mutational pressure and selective constraint. Meanwhile, coding sequence length and the hydrophobicity of proteins could also influence the codon usage patterns. In short, codon usage pattern analysis and determination of optimal codons has laid an important theoretical basis for genetic engineering, gene prediction and molecular evolution studies in apple.

关键词： apple the synonymous codon usage patterns codon bias RSCU

Metal-Free Synthesis of β-Bromoalkenyl Sulfides via Deoxygenative Bromination/Olefination/Sulfenylation of Ketones with SulfonylHydrazides and Pyridinium Tribromide

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Chinese Journal of Chemistry 2018年第11期36卷 1063-1068页

作者： Yishu Bao Lingyu zhong Qiaodan hou Qingfa Zhou Fulai Yang State Key Laboratory of Natural Medicines Department of Organic Chem- istry China Pharmaceutical University Nanjing Jiangsu 210009 China

A novel metal‐free method for synthesis of β‐bromoalkenyl sulfides via deoxygenative bromination/olefination/sulfenylation process using commercially available ketones, sulfonyl hydrazides and pyridinium tribromide as starting materials has been developed. In this reaction, pyridinium tribromide plays the role of oxidant and substrate, wherein water and molecular nitrogen are generated as environmentally benign by‐products. Preliminary investigation revealed that vinyl bromides were critical intermediate. Importantly, this protocol not only obviates the use of alkynes and traditional sulfenylating agents, but also reveals that ketones can be used as precursors of vinyl bromides.

关键词： ketones sulfonyl hydrazides deoxygenative β‐bromoalkenyl sulfides pyridinium tribromide

Balancing method without trial weights for rotor systems based on similitude scale model

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Frontiers of Mechanical Engineering 2018年第4期13卷 571-580页

作者： Ruiduo YE Liping WANG Xiaojie hou zhong LUO Qingkai HAN School of Mechanical Engineering and Automation Northeastern University Shenyang 110819 China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern University Shenyang 110819 China School of Mechanical Engineering Dalian University of TechnologyDalian 116000 China

A balancing method without trial weights based on the dynamic similitude scale model was proposed as a solution to the balancing problem of a large-scale rotor system. This method could be used to directly obtain the required coefficients for the balancing problem of the prototype system through a similarity model test without a prototype test. Thus, the weight test process of the prototype system was effectively eliminated in the proposed balancing method. First, with the rotor system as the research object, the analytical expression of the influence coefficient was derived on the basis of rotor dynamics theory. Then, through calculation and dimen- sional analysis methods, the similitude relationships of the rotor system and the influence coefficient were deduced on the basis of dynamic similitude theory. The correctness of the proposed similitude relationships was verified through numerical simulation and experiment. The balancing method without trial weights was proposed based on the similitude relationship of the influence coefficient. The effect of the balancing method without trial weights was compared with that of the traditional influence coefficient method through numerical simulation, and the results verified the correctness and effectiveness of the proposed balancing method. The results of this study provide theoretical supplements for the balancing method and the similitude design of the rotor system.

关键词： rotor system dynamic similitude balancing,without trial weights influence coefficient

Flooding attack and defence in Ad hoc networks

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Journal of Systems Engineering and Electronics 2006年第2期17卷 410-416页

作者： Yi Ping hou Yafei zhong Yiping Zhang Shiyong Dai Zhoulin School of Information Security Engineering Shanghai Jiaotong Univ. Shanghai 200030 P. R. China Dept. of Computing and Information Technology Fudan Univ. Shanghai 200433 P. R. China Graduate School of Engineering Kochi University of Technology Rochi 782-8502 Japan.

Mobile ad hoc networks are particularly vulnerable to denial of service （DOS） attacks launched through compromised nodes or intruders. In this paper, we present a new DOS attack and its defense in ad hoc networks. The new DOS attack, called AA hoc Flooding Attack（AHFA）, is that intruder broadcasts mass Route Request packets to exhaust the communication bandwidth and node resource so that the valid communication can not be kept. After analyzed AM hoc Flooding Attack, we develop Flooding Attack Prevention （FAP）, a genetic defense against the AM hoc Flooding Attack. When the intruder broadcasts exceeding packets of Route Request, the immediate neighbors of the intruder record the rate of Route Request. Once the threshold is exceeded, nodes deny any future request packets from the intruder. The results of our implementation show FAP can prevent the AM hoe Flooding attack efficiently.

关键词： computer networks security mobile Ad hoe networks routing protocol denial of service Ad hoc flooding attack.

Reduction of Electron Leakage of AlGaN-Based Deep Ultraviolet Laser Diodes Using an Inverse-Trapezoidal Electron Blocking Layer

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Chinese Physics Letters 2020年第2期37卷 55-59页

作者： zhong-Qiu Xing Yong-Jie Zhou Yu-huai Liu Fang Wang National Joint Research Center for Electron Materials and Systems Zhengzhou UniversityZhengzhou 450001 International Joint Laboratory of Electron Materials and Systems Zhengzhou UniversityZhengzhou 450001 School of Information Engineering Zhengzhou UniversityZhengzhou 450001 School of Physics and Electron Engineering Xinyang Normal UniversityXinyang 464000

To improve the optical and electrical properties of AlGaN-based deep ultraviolet lasers,an inverse-trapezoidal electron blocking layer is *** with three different structural electron blocking layers of rectangular,trapezoidal and inverse-trapezoidal structures are *** energy band,electron concentration,electron current density,P-I and V-I characteristics,and the photoelectric conversion efficiency of different structural devices are investigated by *** results show that the optical and electrical properties of the inversetrapezoidal electron blocking layer laser are better than those of rectangular and trapezoidal structures,owing to the effectively suppressed electron leakage.

关键词： AlGaN Electron inverse

Effects of Custom-made Insoles on Plantar Biomechanics and Upper Extremity Muscle Performance

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Current Medical Science 2022年第1期42卷 159-168页

作者： Yi XU Qing-hua hou Xiu-lan HAN Chu-huai WANG Dong-feng HUANG Department of Rehabilitation Medicine the 7th Affiliated HospitalSun-Yat Sen UniversityShenzhen 518107China Guangdong Provincial Engineering Technology Research Center for Rehabilitation Medicine and Clinical Translation Guangzhou 510080China Clinical Neuroscience Center The 7th Affiliated HospitalSun Yat-sen UniversityShenzhen 518107China Department of Rehabilitation Medicine The 1st Affiliated HospitalSun-Yat Sen UniversityGuangzhou 510080China

Objective:To investigate the effectiveness of molding custom-made insoles for female patients with foot ***:The study included 20 patients whose insoles were prescribed according to biomechanical evaluations and molde... 详细信息

关键词： shoes insole therapeutics biomechanics foot pain

Rectangular 3-snip punctoplasty versus punch punctoplasty with silicone intubation for acquired external punctal stenosis:a prospective randomized comparative study

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International Journal of Ophthalmology(English edition) 2021年第6期14卷 849-854页

作者： Xin Cao Zi-zhong Hu Ying Wu Yu Song Qing-huai Liu Department of Ophthalmology the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Ophthalmology the Second Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina

AIM:To evaluate the effectiveness of rectangular 3-snip punctoplasty versus punch punctoplasty via Kelly punch with silicone intubation for the management of acquired external punctal stenosis(AEPS).METHODS:A prospective,randomized,comparative study was performed on 123 eyes of 94 patients with *** were recruited into either group of rectangular 3-snip punctoplasty(group A)or group of punch punctoplasty with silicone intubation(group B).Outcomes measured were Munk score,grade of punctal stenosis,fluorescein dye disappearance time test(FDDT)and tear meniscus height(TMH)6 and 12 mo after ***:Twelve months after surgery,Munk score,FDDT and TMH significantly decreased in both groups compared with the baseline(all P<0.05),and grade of punctal stenosis increased significantly(P<0.05).The grade of punctal stenosis,Munk score,FDDT and TMH were better in group B compared with group A at 6 or 12 mo(all P<0.05).There was a positive correlation between TMH and Munk score(R=0.655,P<0.001).At the last followed-up,anatomical success was noted in 96.7%eyes in group A and 98.4%eyes in group B(P=0.613).CONCLUSION:Punch punctoplasty via Kelly punch with silicone intubation achieves better outcomes than rectangular 3-snip *** new technique is a simple,minimally invasive,with high anatomical and functional success in patients with AEPS.

关键词： acquired external punctal stenosis punctoplasty Kelly punch