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Experiments that led to the first gene-edited babies: the ethical failings and the urgent need for better governance

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第1期20卷 32-38页

作者： Jing-ru LI Simon WALKER Jing-bao NIE xin-qing zhang Bioethics Center Dunedin School of Medicine University of Otago School of Humanities and Social Sciences Peking Union Medical College

The rapid developments of science and technology in China over recent decades, particularly in biomedical research, have brought forward serious challenges regarding ethical governance. Recently, Jian-kui HE, a Chinese scientist, claimed to have "created" the first gene-edited babies, designed to be naturally immune to the human immunodeficiency virus(HIV). The news immediately triggered widespread criticism, denouncement, and debate over the scientific and ethical legitimacy of HE’s genetic experiments. China’s guidelines and regulations have banned germline genome editing on human embryos for clinical use because of scientific and ethical concerns, in accordance with the international consensus. HE’s human experimentation has not only violated these Chinese regulations, but also breached other ethical and regulatory norms. These include questionable scientific value, unreasonable risk-benefit ratio, illegitimate ethics review, invalid informed consent, and regulatory misconduct. This series of ethical failings of HE and his team reveal the institutional failure of the current ethics governance system which largely depends on scientist’s self-regulation. The incident highlights the need for urgent improvement of ethics governance at all levels, the enforcement of technical and ethical guidelines, and the establishment of laws relating to such bioethical issues.

关键词： Jian-kui HE Human germline gene editing Human immunodeficiency virus (HIV) Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 Ethical review

A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 339-361页

作者： Tianyi Li xin Gu qing zhang College of Architectural Engineering Jiangsu Open UniversityNanjing210036China Department of Engineering Mechanics Hohai UniversityNanjing211100China

This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration *** model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics *** simulations conducted on granite and ceramic materials,this model demonstrates its *** successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during *** account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental *** coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials.

关键词： Peridynamic differential operator thermomechanical coupling heterogeneity numerical simulation

Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 106-117页

作者： xin Shao qing Liu Zicheng xin Jiangshan zhang Tao Zhou Shaoshuai Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Engineering Research Center of MES Technology for Iron&Steel Production Ministry of EducationBeijing 100083China Laiwu Iron and Steel Group Yinshan Section Steel Co. Ltd.Jinan 271104China

The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter.

关键词： basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model

Functionalization of nanodiamond with epoxy monomer

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Chinese Chemical Letters 2011年第4期22卷 485-488页

作者： Huan Huan zhang Ya Ting Liu Rong Wang Xiao Yan Yu Xiong Wei Qu qing xin zhang Institute of Polymer Science and Engineering School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China

A novel nanodiamond-epoxy derivative（ND-EP） was synthesized by grafting epoxy monomers onto the surface of nanodiamond（ND）,and characterized by FTIR and *** ratio of grafted epoxy groups was determined to be 32.5 wt% by *** developed methodology provides an efficient method for the functionalization of nanodiamond material,which enables a variety of advanced engineering and biomedical applications of ND.

关键词： Nanodiamond Epoxy Surface modification

Optimal Strategy for Aircraft Pursuit-evasion Games via Self-play Iteration

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Machine Intelligence Research 2024年第3期21卷 585-596页

作者： xin Wang qing-Lai Wei Tao Li Jie zhang State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China Institute of Systems Engineering Macao University of Science and TechnologyMacao999078China

In this paper,the pursuit-evasion game with state and control constraints is solved to achieve the Nash equilibrium of both the pursuer and the evader with an iterative self-play *** the condition where the Hamiltonian formed by means of Pontryagin’s maximum principle has the unique solution,it can be proven that the iterative control law converges to the Nash equilibrium ***,the strong nonlinearity of the ordinary differential equations formulated by Pontryagin’s maximum principle makes the control policy difficult to figured *** the system dynamics employed in this manuscript contains a high dimensional state vector with *** practical applications,such as the control of aircraft,the provided overload is ***,in this paper,we consider the optimal strategy of pursuit-evasion games with constant constraint on the control,while some state vectors are restricted by the function of the *** address the challenges,the optimal control problems are transformed into nonlinear programming problems through the direct collocation ***,two numerical cases of the aircraft pursuit-evasion scenario are given to demonstrate the effectiveness of the presented method to obtain the optimal control of both the pursuer and the evader.

关键词： Differential games pursuit-evasion games nonlinear control optimal control Nash equilibrium solution

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： Yan-li xin Zhi-ying Gao Bo Tian qing-dong zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

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Petroleum Science 2024年第3期21卷 1597-1610页

作者： xin-Yu Fang Gang Yao qing-qing Zheng Ping-Min zhang Di Wu Feng-Lin Niu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China Department of Mathematics College of ScienceChina University of Petroleum(Beijing)Beijing102249China College of Geophysics China University of Petroleum(Beijing)Beijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005UA

P-and S-wave separation plays an important role in elastic reverse-time *** can reduce the artifacts caused by crosstalk between different modes and improve image *** addition,P-and Swave separation can also be used to better understand and distinguish wave types in complex *** present,the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering,low-rank approximation,and vector Poisson *** of these methods require multiple Fourier transforms or the calculation of large matrices,which require high computational costs for problems with large *** this paper,an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial *** 2D problems,the computational complexity required by this method is 1/2 of the methods based on solving a vector Poisson ***,compared with existing methods based on pseudoHelmholtz decomposition operators,this method can significantly reduce the computational *** examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition

Identification of human microRNA-disease association via low-rank approximation-based link propagation and multiple kernel learning

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Frontiers of Computer Science 2024年第2期18卷 217-229页

作者： Yizheng WANG xin zhang Ying JU qing LIU Quan ZOU Yazhou zhang Yijie DING Ying zhang Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324000China Beidahuang Industry Group General Hospital Harbin 150088China School of Informatics Xiamen UniversityXiamen 361005China Department of Anesthesiology Hospital(T.C.M)Affiliated to Southwest Medical UniversityLuzhou 646000China Software Engineering College Zhengzhou University of Light IndustryZhengzhou 450002China

Numerous studies have demonstrated that human microRNAs(miRNAs)and diseases are associated and studies on the microRNA-disease association(MDA)have been *** developed a model using a low-rank approximation-based link propagation algorithm with Hilbert–Schmidt independence criterion-based multiple kernel learning(HSIC-MKL)to solve the problem of the large time commitment and cost of traditional biological experiments involving miRNAs and diseases,and improve the model *** constructed three kernels in miRNA and disease space and conducted kernel fusion using *** propagation uses matrix factorization and matrix approximation to effectively reduce computation and time *** results of the experiment show that the approach we proposed has a good effect,and,in some respects,exceeds what existing models can do.

关键词： human miRNA-disease association multiple kernel learning link propagation miRNA similarity disease similarity

Physics of cavitation near particles

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Journal of Hydrodynamics 2024年第1期36卷 102-118页

作者： Jia-xin Yu Xiao-yu Wang Jun-wei Shen Jin-sen Hu Xiang-qing zhang Da-qing He Yu-ning zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The combined effect of cavitation and silt abrasion presents a great challenge and threat to secure the operation and the efficiency of hydraulic machineries working in sediment-laden *** present paper critically reviews the current research progress on the interaction mechanisms of the bubbles and the ***,the analytical models including boundary treatment methods for predicting the jet dynamics of the bubble collapse near particles are ***,the bubble collapsing dynamics,jet dynamics and shock wave characteristics near particles are revealed both experimentally and ***,the bubble-particle-wall system is investigated with a focus on microjets.

关键词： Cavitation bubble particle jet shock wave