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Identification and classification of promoters using the attention mechanism based on long short-term memory

Frontiers of Computer Science 2022年第4期16卷 103-109页

作者： Qingwen li lichao Zhang Lei Xu Quan Zou Jin Wu Qingyuan Li Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610054China State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of SciencesBeijing100101China Forestry and Fruit Tree Research Institute Wuhan Academy of Agricultural SciencesWuhan430075China School of Intelligent Manufacturing and Equipment Shenzhen Institute of Information TechnologyShenzhen518172China School of Electronic and Communication Engineering Shenzhen PolytechnicShenzhen518055China School of Management Shenzhen PolytechnicShenzhen518055China

A promoter is a short region of DNA that can bind RNA polymerase and initiate gene transcription.It is usually located directly upstream of the transcription initiation site.DNA promoters have been proven to be the main cause of many human diseases,especially diabetes,cancer or Huntington’s disease.Therefore,the classification of promoters has become an interesting problem and has attracted the attention of many researchers in the field of bioinformatics.Various studies have been conducted in order to solve this problem,but their performance still needs further improvement.In this research,we segmented the DNA sequence in a k-mers manner,then trained the word vector model,inputted it into long short-term memory(LSTM)and used the attention mechanism to predict.Our method can achieve 93.45%and 90.59%cross-validation accuracy in the two layers,respectively.Our results are better than others based on the same data set,and provided some ideas for accurately predicting promoters.In addition,this research suggested that natural language processing can play a significant role in biological sequence prediction.

关键词： promoter bioinformatics natural language processing attention mechanism

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Novel porous ceramic with high strength and thermal performance using MA hollow spheres

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Progress in Natural Science:Materials International 2022年第6期32卷 732-738页

作者： Anbang Chen Lang li Chong Wang qingyuan Wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province College of Architecture and Environment Sichuan University MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and Environment Sichuan University

The objective of this work is to obtain a multifunctional porous ceramic material at low cost with improved properties and that can be used in many applications like:thermal and acoustic insulation,refractory support and hot gas filtration elements.To that end,a novel facile strategy to fabricate porous ceramics by foaming and poreforming agent methods using magnesia-aluminum spinel hollow spheres(MASHSs) was reported for the first time,in which calcium aluminate cement(CAC) served as high-temperature binder.The influence of temperature ranging from 1500℃ to 1700℃ on the thermal conductivity,porosity and mechanical strength were investigated.The results show that,the obtained MASHSs ceramic exhibits high porosity(67.2-71.9%) and thermal conductivity(0.18-0.38 W/mK),and compressive strength(6.1-17.1 MPa),which is mainly due to the change in crack directions and microstructure optimization with the prolong of firing temperature.The crack directions changed from the surface of MASHSs to the interior MASHSs,which consumes more crack energy,and thus leading to the excellent mechanical performance.What is more,the introduction of MASHSs makes it difficult to lose heat at elevated temperature,and thereby improving the thermal conductivity of materials.

关键词： MA hollow Spheres Porous ceramics Thermal conductivity Mechanical property

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Microstructures and electrochemical behaviors of casting magnesium alloys with enhanced compression strengths and decomposition rates

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Journal of Magnesium and Alloys 2023年第4期11卷 1213-1223页

作者： Xuewu li qingyuan Yu Xi Chen Qiaoxin Zhang State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Xi’an University of Science and Technology58 Yanta RoadXi’an 710054China School of Mechanical and Electronic Engineering Wuhan University of Technology122 Luoshi RoadWuhan 430070China

New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochemical and compression tests are conducted to assess the feasibility as decomposable material.Morphology,composition,phase and distribution are characterized to investigate decomposition mechanism.Results indicate that floccule,substrate component and reticulate secondary phase are formed on as-prepared surface.Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process.Furthermore,as decomposition time and zinc content increase,couple corrosion intensifies,resulting in gradually enhanced decomposition rate.Rapid sample decomposition is mainly due to basal anode dissolution,micro particle exfoliation and poor decomposition resistance of corroding product.Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.

关键词： Magnesium alloy Corrosion dissolution Compression strength Electrochemical test Decomposition mechanism

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Experimental study on the flow behaviour of water-sand mixtures in fractured rock specimens

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International Journal of Mining Science and Technology 2021年第3期31卷 377-385页

作者： Boyang Zhang qingyuan He Zhibin lin Zhenhua li School of Civil Engineering Henan Polytechnic UniversityJiaozuo 454000China State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining and TechnologyXuzhou 221116China School of Minerals and Energy Resources Engineering UNSW SydneySydneyNSW 2052Australia

The study of flow behaviour of water-sand mixtures in fractured rocks is of great necessity to understand the producing mechanism and prevention of water inrush and sand gushing accidents.A self-developed seepage test system is used in this paper to conduct laboratory experiments in order to study the influence of the particle size distribution,the void ratio,and the initial mass of Aeolian sand on the flow behavior.It is concluded that the water flow velocity is insensitive to the initial mass of the Aeolian sand but increases with the power exponent in the Talbot formula and the specimen height.The outflow of the Aeolian sand increases with the power exponent in the Talbot formula,the specimen height,and the initial mass of the Aeolian sand.Besides,the outflow of the Aeolian sand changes exponentially with the water flow velocity.Finally,it is found that the fractured specimen has a maximum sand filtration capacity beyond which the outflow of the Aeolian sand significantly increases with the initial mass of the Aeolian sand.

关键词： Water inrush and sand gushing accidents Seepage flow of water-sand mixtures Fractured specimens Sand filtration capacity

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Microcrack fracturing of coal specimens under quasi-static combined compression-shear loading

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1014-1026页

作者： qingyuan He Yingchun li Danqi li Chengguo Zhang State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining and TechnologyXuzhou221116China School of Minerals and Energy Resources Engineering University of New South WalesSydney2052Australia State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian116024China Department of Civil Engineering Monash UniversityClaytonMelbourneVIC3800Australia

Coal pillars are usually loaded under combined compression-shear stresses at underground coal mines.Their long-term stability is critical to the utilization of underground structures,such as underground reservoirs at coal mines.In this study,a modified rock property testing system was used to explore the mechanical properties of coal specimens under quasi-static combined compression-shear loading conditions.The acoustic emission technique was applied to investigating the microcrack fracturing of coal specimens at various inclination angles.The experimental results show that specimen inclination has remarkable effects on the microcrack initiation,microcrack damage and ultimate failure of the coal specimen.The failure mode of the coal specimen tends to transit from axial splitting to shear failure with increasing specimen inclination,and its peak strength is closely associated with the microcrack damage threshold.In practice,it is recommended to consider coal strength under combined compression-shear loading when using empirical pillar strength formulae so that the effect of pillar inclination can be included.

关键词： Microcrack initiation(CI) Microcrack damage(CD) Microcrack fracturing Acoustic emission Coal properties

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Sustainability performance analysis of environment innovation systems using a two-stage network DEA model with shared resources

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Frontiers of Engineering Management 2022年第3期9卷 425-438页

作者： Jiangjiang YANG Jie WU Xingchen li qingyuan ZHU School of Management University of Science and Technology of ChinaHefei 230026China School of Accounting Nanjing Audit UniversityNanjing 211815China College of Economics and Management Research Center for Soft Energy ScienceNanjing University of Aeronautics and AstronauticsNanjing 211106China

The term environmental innovation system refers to an innovation network composed of enterprises,universities,and research institutions involved in the development and diffusion of environmental technology,with the participation of a government.An environmental innovation system not only exerts important impact on the achievement of carbon neutrality but also affects social and economic activities.Investigations on environmental innovation system performance constantly assume a singlestage independent system while ignoring its internal structure.However,such systems are composed of environmental innovation research and development(R&D)and environmental innovation conversion subsystems.A two-stage data envelopment analysis(DEA)model is developed in this study to analyze the efficiency of Chinese regional environmental innovation system by opening the"black box"and considering shared resources.Empirical results indicated that China presents high overall environmental innovation efficiency although some regions need to improve.Regions with low efficiencies in both environmental innovation R&D(EIR)and environmental innovation conversion(EIC)subsystems should expand their investment in and strengthen the management of environmental innovation resources.Regions with low EIR efficiency should improve the absorption and transformation of environmental innovation achievements.Regions with low EIC efficiency should increase investment in the commercialization of environmental innovation achievements and encourage green economy industries,such as new energy,art,tourism,and environmental protection.

关键词： data envelopment analysis environmental efficiency environmental innovation system shared resources two-stagestructure

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Preparation and adsorption performance of multi-morphology H_(1.6)Mn_(1.6)O_(4) for lithium extraction

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Chinese Journal of Chemical Engineering 2021年第6期34卷 68-76页

作者： Xiulei li Baifu Tao qingyuan Jia Ruili Guo Chemistry and Chemical Engineering Key Laboratory for Green Process of Chemical Engineering of Xinjiang BingtuanShihezi UniversityShihezi 832003China

In this paper,a lithium-ion sieve(liS)with different morphologies,such as rod-like(liS-R),spherical(liS-S),flower-like(liS-F),and three-dimensional macroporous-mesoporous(liS-3D),was prepared by hydrothermal synthesis,solid reaction,and hard-template synthesis.The results showed that the liS with different morphologies presented great differences in specific surface area,pore volume,adsorption selectivity,and structure stability.liS-3D with highest specific surface area and pore volume displayed the maximum adsorption capacity and adsorption rate,but the stability of liS-3D was poor because of the manganese dissolution.By comparison,liS-S has the best structural stability while maintaining a satisfactory adsorption capacity(35.02 mg·g^(-1))and adsorption rate.The liS-S remained about 90%of the original adsorption capacity after five cycles of adsorption-desorption process.In addition,in the simulated brine system(the magnesium to lithium ratio of 400),the liS-S exhibited the highest selectivity(α_(Mg)^(li))of 425.14.In sum,the liS-S with good morphology is a potential adsorbent for lithium extraction from brine.

关键词： lithium-ion sieve Morphologies lithium extraction Brine Adsorbent

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互联网对性别角色观念与家庭分工的影响

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人口学刊 2024年第3期46卷 48-65页

作者：李青原北京大学国家发展研究院北京100871

性别平等关系社会经济发展和民生福祉,互联网等数字技术的快速发展为促进性别角色观念和性别分工平等提供了有利条件。与教育等影响因素相比,互联网在信息、知识和文化传播及共享方面独具优势,可能在“男外女内”等传统性别角色观念向... 详细信息

性别平等关系社会经济发展和民生福祉,互联网等数字技术的快速发展为促进性别角色观念和性别分工平等提供了有利条件。与教育等影响因素相比,互联网在信息、知识和文化传播及共享方面独具优势,可能在“男外女内”等传统性别角色观念向“性别平等”现代性别角色观念转变的进程中发挥重要作用;由于观念常常主导行为且考虑互联网的经济效应,互联网的发展也可能促使传统家庭分工模式发生变化。性别角色观念和家庭分工趋于平等不仅有助于缓解女性遭遇的工作-家庭冲突,也将减轻传统性别角色定位给男性带来的压力。本研究利用“宽带中国”政策准实验,使用中国综合社会调查(CGSS)和中国家庭追踪调查(CFPS)数据,构建双重差分模型研究互联网对性别角色观念和家庭分工的影响。一方面,从性别角色观念的转变来看,互联网能够显著促使个体形成现代性别角色观念,使个体在能力、职业权利和家务等维度上的性别角色观念更加平等。对女性和男性分组回归发现两者在互联网的影响下均持有更加平等的性别角色观念,并且男性受到的影响更大,意味着未来以互联网为核心的数字技术的普及和深化可能在更大范围上缩小男女性别角色观念差距。进一步分析主要影响机制发现互联网拓展了人们的信息获取渠道,促使人们接触和了解更多有关性别平等的信息,增加了人们对性别平等的关注度,进而影响人们的性别角色观念。另一方面,从家庭分工的变化来看,当前互联网在改变性别角色观念的同时对家庭分工的影响仍然有限。尽管妻子的工作时长相对于丈夫有所增加,但夫妻家务时间配置即家务分工未发生显著改变,“男主外”已松动而“女主内”依旧稳固,这可能加重女性在工作和家庭上的负担。进一步检验表明家庭分工的转变仍受到传统社会规范和相对资源等因素的影响。与较多受到传统社会规范约束的地区、丈夫相对资源较多的家庭相比,在较少受到传统社会规范约束的地区、妻子相对资源较多的家庭中,妻子的工作时长相对于丈夫显著增加。在互联网的作用下,性别平等观念得以被广泛接受且男女性别角色观念差距减小,然而性别分工平等进展较为缓慢,性别平等实践任重道远。

关键词：互联网性别角色观念家庭分工性别平等

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Adhesive Contact of a One-Dimensional Hexagonal Quasicrystal Half-Space Punched by a Spherical Indenter

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Acta Mechanica Solida Sinica 2022年第5期35卷 787-799页

作者： Peidong li Yuwei liu Songhan Zhang Bingmei Shao Haidong Fan qingyuan Wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu610065China Chengdu University Chengdu610106China School of Civil Engineering Dalian University of TechnologyDalian116024China

This paper develops the adhesive contact theory for a one-dimensional hexagonal quasicrystal half-space punched by a spherical indenter on the basis of the classical adhesive contact models involving the Johnson–Kendall–Roberts(JKR)model,the Maugis–Dugdale(MD)model and the Derjaguin–Muller–Toporov(DMT)model.By using the superposition principle combined with the Griffith energy balance,all the significant physical quantities for adhesive contact,such as the energy release rate,indentation force,penetration depth,contact radius and pull-out force,are obtained for different models.The result for the DMT model is derived from the MD solution through a limiting procedure.A numerical calculation is carried out to verify the present analytical solutions,to compare different contact models,and to analyze the influence of the phason field on the results.It is indicated that the effect of the phason field on the result for the MD model is pronounced,especially for a small contact radius.However,the phason effect on the JKR and DMT results is not significant.The present solution can serve as a theoretical basis for nano-indentation and atomic force microscopy to measure the material properties of quasicrystals.

关键词： Adhesive contact Quasicrystal Spherical indenter Analytical solution

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Long-term trend of water vapor over the Tibetan Plateau in boreal summer under global warming

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Science China Earth Sciences 2022年第4期65卷 662-674页

作者： Jingwen YU Qingquan li Yihui DING Jie ZHANG qingyuan WU Xinyong SHEN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory on Climate and Environment ChangeNanjing University of Information Science&TechnologyNanjing 210044China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

In this study,the long-term trend of water vapor over the Tibetan Plateau(TP)in boreal summer is investigated by using observation and reanalysis data from 1979 to 2019.The historical experiment simulations of 19 models that participated in the Coupled Model Intercomparison Project phase 6(CMIP6)are evaluated,and the future variation tendency under four emission scenarios is projected.The results indicate that the water vapor content and the net water vapor budget over the TP show notable increasing trends,which are mainly manifested by a significant increase in the net water vapor import and a significant decrease in the water vapor export on the eastern boundary of the TP.This is mainly due to an anomalous anticyclone from Lake Baikal to the Mongolian Plateau.The CMIP6 multi-model ensemble can well simulate the variation characteristics of the TP net water vapor budget.The projection results indicate that by the end of the twenty-first century,the water vapor content,the net water vapor import and precipitation over the TP will increase.Under a high-emissions scenario and compared with the current period(1991–2014),these three variables will increase by 47.99%,59.77%and 18.59%in the long term(2081–2100),respectively.The significant enhancement of meridional water vapor transport over the northern TP may be the main reason for the increase in humidity over the TP.

关键词： Tibetan Plateau Boreal summer Water vapor transport Long-term trend Projection

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