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Targeted DNA N^(6)-methyladenine editing by dCas9 fused to METTL4 in the lepidopteran model insect Bombyx mori

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Insect science 2024年第2期31卷 646-650页

作者： Feng Chen Hao Guo Weiqun Lan Mingyi Zhou Wenjng Geng Guanwang Shen Ping Lin Qingyou Xia Ping Zhao Zhiqing Li Integrative science center of Germplasm Creation in Western China(CHONGQING)science City Biological Science Research CenterSouthwest UniversityChongqingChina Chongqing Key Laboratory of Sericultural science Chongqing Engineering and Technology Research Center for Novel Silk MaterialsSouthwest UniversityChongqingChina

Dear Editor,N^(6)-Methyladenine(6mA)DNA modification is an important epigenetic mechanism with roles in regulating gene expression,nucleosome positioning,DNA damage repair,and cell cycle progression(Heyn&Esteller,2015;Luo et al.,2015;Boulias&Greer,2022).Despite progress in understanding the biological functions of 6mA,the contribution of individual 6mA installations on site-specific target genes is largely unknown,and therefore deciphering the molecular mechanism of 6mA in target gene expression has been difficult.

关键词： adenine fused Bombyx

Efficient Dynamic Locomotion of Quadruped Robot via Adaptive Diagonal Gait

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Journal of Bionic Engineering 2024年第1期21卷 126-136页

作者： Jian Bi Teng Chen Xuewen Rong Guoteng Zhang Guanglin Lu Jingxuan Cao Han Jiang Yibin Li The center for Robotics School of Control Science and EngineeringShandong UniversityJi Nan 250000China

Quadruped animals in the nature realize high energy efficiency locomotion by automatically changing their gait at different *** by this character,an efficient adaptive diagonal gait locomotion controller is designed for quadruped robot.A unique gait planning method is proposed in this *** the speed of robot varies,the gait cycle time and the proportion of stance and swing phase of each leg are adjusted to form a variety of *** optimal joint torque is calculated by the controller combined with Virtual Model Control(VMC)and Whole-Body Control(WBC)to realize the desired *** gait and step frequency of the robot can automatically adapt to the change of *** experiments are done with a quadruped robot made by our laboratory to verify that the gait can change automatically from slow-trotting to flying-trot during the period when speed is from 0 to 4 m/*** ratio of swing phase is from less than 0.5 to more than 0.5 to realize the running motion with four feet off the *** have shown that the controller can indeed consume less energy when robot runs at a wide range of speeds comparing to the basic controller.

关键词： Quadruped robot Gait transition Adaptive gait Energy efficiency

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： Yong-Pan Duan Run-Qiang Chi Bao-Jun Pang Yuan Cai Hypervelocity Impact Research center Harbin Institute of TechnologyHarbin150080China College of science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms

Visual Semantic Segmentation Based on Few/Zero-Shot Learning:An Overview

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1106-1126页

作者： Wenqi Ren Yang Tang Qiyu Sun Chaoqiang Zhao Qing-Long Han Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National Key Laboratory of Air-Based Information Perception and fusion Aviation Industry Corporation of ChinaLuoyang 471000China School of science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Visual semantic segmentation aims at separating a visual sample into diverse blocks with specific semantic attributes and identifying the category for each block,and it plays a crucial role in environmental *** learning-based visual semantic segmentation approaches count heavily on largescale training data with dense annotations and consistently fail to estimate accurate semantic labels for unseen *** obstruction spurs a craze for studying visual semantic segmentation with the assistance of few/zero-shot *** emergence and rapid progress of few/zero-shot visual semantic segmentation make it possible to learn unseen categories from a few labeled or even zero-labeled samples,which advances the extension to practical ***,this paper focuses on the recently published few/zero-shot visual semantic segmentation methods varying from 2D to 3D space and explores the commonalities and discrepancies of technical settlements under different segmentation ***,the preliminaries on few/zeroshot visual semantic segmentation,including the problem definitions,typical datasets,and technical remedies,are briefly reviewed and ***,three typical instantiations are involved to uncover the interactions of few/zero-shot learning with visual semantic segmentation,including image semantic segmentation,video object segmentation,and 3D ***,the future challenges of few/zero-shot visual semantic segmentation are discussed.

关键词： Visual segmentation separating

Stabilization Controller of An Extended Chained Nonholonomic System With Disturbance:An FAS Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1262-1273页

作者： Zhongcai Zhang Guangren Duan School of Engineering Qufu Normal UniversityRizhao 276826China center for Control science and Technology Southern University of Science and TechnologyShenzhen 518055 center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

This study examines the stabilization issue of extended chained nonholonomic systems(ECNSs)with external *** the existing approaches,we transform the considered system into a fully actuated system(FAS)model,simplifying the stabilizing controller *** implement a separate controller design and propose exponential stabilization controller and finite-time stabilization controller under finite-time disturbance observer(FTDO)for the two system *** addition,we discuss the specifics of global stabilization control *** approach demonstrates that two system states exponentially or asymptotically converge to zero under the provided switching stabilization control strategy,while all other system states converge to zero within a finite time.

关键词： design stabilization system

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： Sheng-wen Xu Shi-yu Dai Teng Zhao center for Quantum science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

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Mode Competition of Low Voltage Backward Wave Oscillator near 500 GHz with Parallel Multi-Beam

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Chinese Journal of Electronics 2024年第2期33卷 488-495页

作者： Xiaoyan ZHAO Jincheng HU Haoran ZHANG Sidou GUO Yuming FENG Lin TANG Kaichun ZHANG Diwei LIU THz center School of Electronic Science and Engineering University of Electronic Science and Technology of China School of Computer science Southwest Petroleum University

A backward wave oscillator with parallel multiple beams and multi-pin slow-wave structure(SWS)operating at the frequency above 500 GHz is studied. Both the cold-cavity dispersion characteristics and CST Particle Studio simulation results reveal that there are obvious mode competition problems in this kind of terahertz *** that the structure of the multi-pin SWS is similar to that of two-dimensional photonic crystals, we introduce the defects of photonic crystal with the property of filtering into the SWS to suppress high-order ***, a detailed study of the effect of suppressing higher-order modes is carried out in the process of changing location and arrangement pattern of the point defects. The stable, single-mode operation of the terahertz source is realized. The simulation results show that the ratio of the output peak power of the higher-order modes to that of the fundamental mode is less than 1.9%. Also, the source can provide the output peak power of 44.8 m W at the frequency of 502.2 GHz in the case of low beam voltage of 4.7 kV.

关键词： Low voltage Filtering Simulation Voltage Photonic crystals Machining Pins

Numerical study of alpha particle loss with toroidal field ripple based on CFETR steady-state scenario

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Chinese Physics B 2024年第1期33卷 503-510页

作者：李钮琦徐颖峰钟方川张德兵 College of science Donghua UniversityShanghai 201620China Member of Magnetic Confinement fusion Research center Ministry of EducationShanghai 201620China Department of Physics East China University of Science and TechnologyShanghai 200237China

Effects of plasma equilibrium parameters on the alpha particle loss with the toroidal field ripple based on the CFETR steady-state scenario have been numerically investigated by the orbit-following code GYCAVA. It is found that alpha particle losses decrease and loss regions become narrower with the plasma current increasing or with the magnetic field decreasing. It is because the ripple stochastic transport and the ripple well loss of alpha particle are reduced with the safety factor decreasing. Decrease of the plasma density and temperature can reduce alpha particle losses due to enhancement of the slowing-down effect. The direction of the toroidal magnetic field can significantly affect heat loads induced by lost alpha particle. The vertical asymmetry of heat loads induced by the clockwise and counter-clockwise toroidal magnetic fields are due to the fact that the ripple distribution is asymmetric about the mid-plane, which can be explained by the typical orbits of alpha particle. The maximal heat load of alpha particle for the clockwise toroidal magnetic field is much smaller than that for the counter-clockwise one.

关键词： alpha particle loss ripple orbit-following tokamak

Effect of Three-High Rotary Piercing Process on Microstructure,Texture and Mechanical Properties of Magnesium Alloy Seamless Tube

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 953-968页

作者： Xiaofeng Ding Zehao Wu Tong Li Jianxun Chen Yuanhua Shuang Baosheng Liu Heavy Machinery Engineering Research center of Education Ministry Taiyuan University of Science and TechnologyTaiyuan030024China College of Materials science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Mg alloy seamless tubes(MASTs)were prepared through three-high rotary piercing process,effect of billet temperature,feed angle and plug advance on microstructure,texture and mechanical properties of tubes were *** effect on the deformation mechanism and improving mechanical properties mechanism of this process for MASTs were *** results show that the grain size could be refined to 11.3-31.1%of the initial grain size and the microstructure was more uniform due to the accumulation of *** formation of high strain gradient at the grain boundary activated the non-basal *** piercing process could change the grain orientation of as-extruded billet and eliminate the initial basal texture to produce new favorable *** the process could accelerate the continuous dynamic recrystallization *** piercing,yield strength of pierced tubes decreased by 6.7%,ultimate tensile strength(UTS)and elongation increased by 32.4 and 45%,respectively,at optimal *** plate-shapedβ_(1)-Mg_(17)Al_(12) orientation transformed from basal plates to prismatic plates,facilitating the increase in UTS and *** decrease size of nanoscale precipitates could reduce the cracking *** critical resolved shear stress ratios of pyramidal(10−11)slip and(11−22)slip to basal slip for the sample including prismatic plates both decreased compared to that including basal *** could enhance the ductility of tube ***,grain boundary sliding could contribute to a better ductility via coordinating deformation and reducing stress concentration during piercing process.

关键词： Mg alloy tube Rotary piercing Microstructure Texture Mechanical properties