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Mutations and intron polymorphisms in voltage-gated sodium channel genes of different geographic populations of Culex pipiens pallens/Culex pipiens quinquefasciatus in China

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Infectious Diseases of Poverty 2024年第2期13卷 6-16页

作者： Wenyu Li Delong Ma Qunzheng Mu Xinxin Zhou Dongdong Hua Chunchun Zhao Qiyong Liu Jun Wang Fengxia Meng State Key Laboratory of Infectious Disease Prevention and Control Department of Vector Biology and ControlNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionWHO Collaborating Centre for Vector Surveillance and ManagementBeijing 102206People’s Republic of China Ningxia Center for Disease Prevention and Control YinChuan 750004NingXiaPeople’s Republic of China Jinan Shizhong Center for Disease Control and Prevention Jinan 250000ShandongChina Vanke School of Public Health Tsinghua UniversityBeijingPeople’s Republic of China Weifang No.2.People’s Hospital Weifang 261000ShandongPeople’s Republic of China beijing Daxing Center for Disease Control and Prevention Beijing 102600People’s Republic of China Jinan Second Maternal and Child Health Hospital Jinan 250000ShandongChina

Background Culex pipiens pallens and Culex pipiens quinquefasciatus are the dominant species of Culex mosquitoes in China and important disease ***-term use of insecticides can cause mutations in the voltage-gated sodium channel(vgsc)gene of mosquitoes,but little is known about the current status and evolutionary origins of vgsc gene in different geographic ***,this study aimed to determine the current status of vgsc genes in *** and *** in China and to investigate the evolutionary inheritance of neighboring downstream introns of the vgsc gene to determine the impact of insecticides on long-term *** Sampling was conducted from July to September 2.2. in representative habitats of 2. provincial-level administrative divisions in *** DNA was extracted from 1308 mosquitoes,the IIS6 fragment of the vgsc gene on the nerve cell membrane was amplified using polymerase chain reaction,and the sequence was used to evaluate allele frequency and knockdown resistance(kdr)*** 11 was used to construct neighborjoining(NJ)*** was used to build a TCS *** There were 6 alleles and 6 genotypes at the L1014 locus,which included the wild-type alleles TTA/L and CTA/L and the mutant alleles TTT/F,TTC/F,TCT/S and TCA/*** geographic populations with a kdr frequency less than 2..00%were mainly concentrated in the regions north of 38°N,and the geographic populations with a kdr frequency greater than 80.00%were concentrated in the regions south of 30°*** frequency increased with decreasing *** within the same latitude,the frequency of kdr in large cities is relatively *** were correlated with the number of *** mutant allele TCA/S has only one intron,the mutant allele TTT/F has three introns,and the wild-type allele TTA/L has 17 *** *** and *** have developed resistance to insecticides in most regions of *** nei

关键词： Culex pipiens pallens Culex pipiens quinquefasciatus vgsc gene Mutation Frequency Intron Haplotype China

Experimental study on the movement of oil spill under freeze-thaw action

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Research in Cold and Arid Regions 2024年第3期16卷 111-120页

作者： ZeLiang Ye JianGuo Lu MingYi Zhang WanSheng Pei ShuTong Li State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengduSichuan 610500China

Oil leakages cause environmental pollution,economic losses,and even engineering safety *** cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw *** this study,a series of laboratory model experiments were carried out on the migration of oil leakage under freeze-thaw action,and the distributions of the soil temperature,unfrozen water content,and displacement were *** results showed that under freeze-thaw action,liquid water in soils migrated to the freezing front and *** the pipe cracked,oil pollutants first gathered at one side of the leak hole,and then moved *** pipe wall temperature affected the soil temperature field,and the thermal influence range below and transverse the pipe wall(35–40 cm)was larger than that above the pipe wall(8 cm)owing to the soil surface *** leaked oil's temperature would make the temperature of the surrounding soil *** would inhibit the cooling of the ***,oil migration was significantly affected by the gravity and water flow *** freeze-thaw action would affect the migration of the oil,which was mainly manifested as inhibiting the diffusion and movement of oil when soils were *** water transport caused by freeze-thaw cycles would also inhibit oil *** research results would provide a scientific reference for understanding the relationship between the movement of oil pollutants,water,and soil temperature,and for establishing a waterheat-mass transport model in frozen soils.

关键词： Freeze-thaw action Oil movement Soil temperature Unfrozen water content Model test

Controlling Town Industry Explosion Hazard in China

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International Journal of Disaster Risk Science 2016年第4期7卷 440-444页

作者： Huixin Yuwen Xueqiu He Xinming Qian Mengqi Yuan School of Mechanical Engineering Beijing Institute of Technology University of Science and technology beijing

This article introduces industrial safety issues encountered in the towns of China,points out the importance of damage control of industrial explosions and disaster management,and puts forward suggestions on safety de... 详细信息

关键词： Damage control Industrial explosion Safety design Town industry

Competitive Occupying of Fe^3+ and Co^3+ Ions into the Lattice B-Sites of Perovskite Crystalline Structure

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Chinese Journal of Structural Chemistry 2017年第2期36卷 217-228页

作者：刘凤祥马宏伟李展平高志明 School of Chemistry Beijing Institute of Technology Analysis and Testing Center Beijing Institute of Technology Analysis Center Tsinghua University

Perovskite-type oxide has a general formula ABO3. Both the lattice A- and lattice B-sites can be occupied by two kinds of metallic ions, forming substituted perovskites such as La（1-x）SrxCoO3-d and LaFexCo（1-x）O3. In the present work, we aim to investigate competitive occupying of Fe（3＋） and Co（3＋） ions into the lattice B-sites of perovskite LaFexCo（1-x）O3 formed under the condition of excess feeding of Fe（3＋） and Co（2.） ions relative to the La（3＋） ions. For this purpose, standard curve of normalized cell volumes（NCVs） of a defined series of perovskites LaFexCo（1-x）O3 versus the x values was plotted. Lattice occupancy of Fe（3＋） ions at the B-sites of the perovskite LaFexCo（1-x）O3 was then determined from the standard curve. It is proved that Fe（3＋） ions were capable of occupying preferentially into the lattice B-sites of the perovskite crystalline structure.

关键词： perovskite calcined substituted excess normalized crystalline metallic calcination methane occupied

Structures and aromaticity of the planar Al_2._2.(n-) (n=1―4) clusters

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Science China Chemistry 2009年第12期52卷 2237-2242页

作者： XU WenGuo,ZHANG YuanChun & ZHAI Lei institute of Chemical Physics,beijing institute of technology,beijing 100081,China 1. institute of Chemical Physics Beijing Institute of Technology Beijing 100081 China

Clusters Al2.2.-(n = 1―4) were theoretically investigated using density functional theory (DFT) methods at the B3LYP/6-311+G* and B3PW91/6-311+G* levels of theory. The calculated results showed that the planar structure (D2. symmetry) of Al2.2.-(n = 1―4) species was the global minimum. And the negative nucleus-independent chemical shift (NICS) value of Al2.2.-(n = 1―4) species indicated the existence of a ring current in the planar structure (D2. symmetry). A detailed molecular orbital (MO) analysis revealed that the planar structures (D2. symmetry) had π aromaticity,which further exhibited the strongly aromatic character for Al2.2.-(n = 1―4) species.

关键词： DFT calculation geometric structure nucleus-independent chemical shift molecular orbital

Elevated peripheral levels of receptor-interacting protein kinase 1(RIPK1)and IL-8 as biomarkers of human amyotrophic lateral sclerosis

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Signal Transduction and Targeted Therapy 2024年第1期9卷 271-278页

作者： Jun Wei Min Li Zhi Ye Xinqian Hu Xiaoyan He Jia Wang Gaofeng Chen Chengyu Zou Daichao Xu Hongbing Zhang Junying Yuan Yunhong Zha institute of Neural Regeneration and Repair and Department of Neurology The First College of Clinical Medical ScienceYichang Central HospitalCollege of Basic Medical ScienceChina Three Gorges UniversityHubei Province Clinical Medical Research Center for Rare Diseases of Nervous SystemYichang 443000China Interdisciplinary Research Center on Biology and Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai Key Laboratory of Aging StudiesShanghai 201210China State Key Laboratory of Common Mechanism Research for Major Diseases Haihe Laboratory of Cell EcosystemDepartment of PhysiologyInstitute of Basic Medical Sciences and School of Basic MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Amyotrophic lateral sclerosis(ALS)is a devastating fatal neurodegenerative disease with no ***-interacting protein kinase 1(RIPK1)has been proposed to mediate pathogenesis of *** has been identified as an old drug that can also inhibit RIPK1 *** conducted a drug-repurposing biomarker study of primidone as a RIPK1 inhibitor using SOD1G93A mice and ALS ***1G93A mice treated with primidone showed significant delay of symptomatic onset and improved motor ***-hundred-sixty-two ALS participants dosed daily with primidone(62.5 mg)completed 2.-week follow-up.A significant reduction was showed in serum levels of RIPK1 and IL-8,which were significantly higher in ALS patients than that of healthy controls(P2.00060149).

关键词： RIPK1 diseases Serum

A new item-based deep network structure using a restricted Boltzmann machine for collaborative filtering

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Frontiers of Information technology & Electronic Engineering 2017年第5期18卷 658-666页

作者： Yong-ping DU Chang-qing YAO Shu-hua HUO Jing-xuan LIU institute of Computer Science Beijing University of TechnologyBeijing 100124China institute of Scientific and Technical information of China Beijing 100038China

The collaborative filtering(CF) technique has been widely used recently in recommendation systems. It needs historical data to give predictions. However, the data sparsity problem still exists. We propose a new item-based restricted Boltzmann machine(RBM) approach for CF and use the deep multilayer RBM network structure, which alleviates the data sparsity problem and has excellent ability to extract features. Each item is treated as a single RBM, and different items share the same weights and biases. The parameters are learned layer by layer in the deep network. The batch gradient descent algorithm with minibatch is used to increase the convergence speed. The new feature vector discovered by the multilayer RBM network structure is very effective in predicting a rating and achieves a better result. Experimental results on the data set of MovieL ens show that the item-based multilayer RBM approach achieves the best performance, with a mean absolute error of 0.642. and a root-mean-square error of 0.7843.

关键词： Restricted Boltzmann machine Deep network structure Collaborative filtering Recommendation system

Recent advancements in optical microstructure fabrication through glass molding process

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Frontiers of Mechanical Engineering 2017年第1期12卷 46-65页

作者： Tianfeng ZHOU Xiaohua LIU Zhiqiang LIANG Yang LIU Jiaqing XIE Xibin WANG Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology Beijing 100081 China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081 China

Optical microstructures are increasingly applied in several fields, such as optical systems, precision measurement, and microfluid chips. Microstructures include microgrooves, microprisms, and microlenses. This paper presents an overview of optical microstructure fabrication through glass molding and highlights the applications of optical microstructures in mold fabrication and glass molding. The glass-mold interface friction and adhesion are also discussed. Moreover, the latest advance- ments in glass molding technologies are detailed, including new mold materials and their fabrication methods, viscoelastic constitutive modeling of glass, and micro- structure molding process, as well as ultrasonic vibration- assisted molding technology.

关键词： optical microstructure microgroove micro-lens glass molding process single-point diamond cutting

Preparation of carbon nanotubes by ethanol catalytic combustion technique using nickel salt as catalyst precursor

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中国有色金属学会会刊：英文版 2006年第B01期16卷 381-384页

作者：李飞邹小平程进张红丹任鹏飞 Research Center for Sensor technology Beijing Information Technology InstituteBeijing 100101China beijing Key Laboratory for Sensor Beijing 100101China

A simple growth technique of carbon nanotubes (CNTs) by combustion of ethanol was developed. In the experiment, copper plate was employed as substrate, nickel nitrate (Ni(NO3)2. and nickel chloride (NiCl2. as catalyst precursor, and ethanol as carbon source. The cleaned copper substrate was dipped into catalyst precursor solution for mounting catalyst precursor particles. The dip-coated substrate was then placed into ethanol flame for about 10 min after drying. The black wool-like production grown on copper plate was obtained. This route is called an ethanol catalytic combustion(ECC) process. The black powders were characterized by means of scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive X-ray spectrometer(EDS) and Raman spectroscopy. The results show that the techique is much simpler and more economical to meet the future broader applications.

关键词：碳纳米管制备催化剂前驱物乙醇催化燃烧技术硝酸镍