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Combining stochastic density functional theory with deep potential molecular dynamics to study warm dense matter 被引量:1
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作者 Tao Chen Qianrui Liu +2 位作者 Yu Liu liang sun Mohan Chen 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期44-57,共14页
In traditional finite-temperature Kohn–Sham density functional theory(KSDFT),the partial occupation of a large number of high-energy KS eigenstates restricts the use of first-principles molecular dynamics methods at ... In traditional finite-temperature Kohn–Sham density functional theory(KSDFT),the partial occupation of a large number of high-energy KS eigenstates restricts the use of first-principles molecular dynamics methods at extremely high temperatures.However,stochastic density functional theory(SDFT)can overcome this limitation.Recently,SDFT and the related mixed stochastic–deterministic density functional theory,based on a plane-wave basis set,have been implemented in the first-principles electronic structure software ABACUS[Q.Liu and M.Chen,Phys.Rev.B 106,125132(2022)].In this study,we combine SDFT with the Born–Oppenheimer molecular dynamics method to investigate systems with temperatures ranging from a few tens of eV to 1000 eV.Importantly,we train machine-learning-based interatomic models using the SDFT data and employ these deep potential models to simulate large-scale systems with long trajectories.Subsequently,we compute and analyze the structural properties,dynamic properties,and transport coefficients of warm dense matter. 展开更多
关键词 STOCHASTIC theory FUNCTIONAL
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Accelerating Factor Xa inhibitor discovery with a de novo drug design pipeline
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作者 Yujing Zhao Qilei Liu +3 位作者 Jian Du Qingwei Meng liang sun Lei Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期85-94,共10页
Small-molecule drugs are essential for maintaining human health. The objective of this study is to identify a molecule that can inhibit the Factor Xa protein and be easily procured. An optimization-based de novo drug ... Small-molecule drugs are essential for maintaining human health. The objective of this study is to identify a molecule that can inhibit the Factor Xa protein and be easily procured. An optimization-based de novo drug design framework, Drug CAMD, that integrates a deep learning model with a mixed-integer nonlinear programming model is used for designing drug candidates. Within this framework, a virtual chemical library is specifically tailored to inhibit Factor Xa. To further filter and narrow down the lead compounds from the designed compounds, comprehensive approaches involving molecular docking,binding pose metadynamics(BPMD), binding free energy calculations, and enzyme activity inhibition analysis are utilized. To maximize efficiency in terms of time and resources, molecules for in vitro activity testing are initially selected from commercially available portions of customized virtual chemical libraries. In vitro studies assessing inhibitor activities have confirmed that the compound EN300-331859shows potential Factor Xa inhibition, with an IC_(50)value of 34.57 μmol·L^(-1). Through in silico molecular docking and BPMD, the most plausible binding pose for the EN300-331859-Factor Xa complex are identified. The estimated binding free energy values correlate well with the results obtained from biological assays. Consequently, EN300-331859 is identified as a novel and effective sub-micromolar inhibitor of Factor Xa. 展开更多
关键词 Chemical product design Mathematical programming method Deep learning Binding affinity Factor Xa inhibitor
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Limited Sea Surface Temperature Cooling Due to the Barrier Layer Promoting Super Typhoon Mangkhut(2018)
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作者 Huipeng WANG Jiagen LI +8 位作者 Junqiang SONG liang sun Fu LIU Han ZHANG Kaijun REN Huizan WANG Chunming WANG Jinrong ZHANG Hongze LENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2156-2172,共17页
This study investigates the impact of the salinity barrier layer(BL)on the upper ocean response to Super Typhoon Mangkhut(2018)in the western North Pacific.After the passage of Mangkhut,a noticeable increase(~0.6 psu)... This study investigates the impact of the salinity barrier layer(BL)on the upper ocean response to Super Typhoon Mangkhut(2018)in the western North Pacific.After the passage of Mangkhut,a noticeable increase(~0.6 psu)in sea surface salinity and a weak decrease(<1℃)in sea surface temperature(SST)were observed on the right side of the typhoon track.Mangkhut-induced SST change can be divided into the three stages,corresponding to the variations in BL thickness and SST before,during,and after the passage of Mangkhut.During the pre-typhoon stage,SST slightly warmed due to the entrainment of BL warm water,which suppressed the cooling induced by surface heat fluxes and horizontal advection.During the forced stage,SST cooling was controlled by entrainment,and the preexisting BL reduced the total cooling by 0.89℃ d-1,thus significantly weakening the overall SST cooling induced by Mangkhut.During the relaxation stage,the SST cooling was primarily caused by the entrainment.Our results indicate that a preexisting BL can limit typhoon-induced SST cooling by suppressing the entrainment of cold thermocline water,which contributed to Mangkhut becoming the strongest typhoon in 2018. 展开更多
关键词 sea surface cooling mixed-layer depth barrier layer TYPHOON
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Creation and annihilation of artificial magnetic skyrmions with the electric field
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作者 程军 孙亮 +5 位作者 张一可 吉同舟 曹荣幸 缪冰锋 赵永刚 丁海峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期132-137,共6页
Recent theory and experiments show that artificial magnetic skyrmions can be stabilized at room temperature without the need for the external magnetic field,casting strong potentials for the device applications.In thi... Recent theory and experiments show that artificial magnetic skyrmions can be stabilized at room temperature without the need for the external magnetic field,casting strong potentials for the device applications.In this work,we study the electric field manipulation of artificial magnetic skyrmions imprinted by Co disks on CoPt multilayers utilizing the micromagnetic simulations.We find that the reversible annihilation and creation of skyrmions can be realized with the electric field via the strain mediated magnetoelastic coupling.In addition,we also demonstrate controllable manipulation of individual skyrmion,which opens a new platform for constructing magnetic field-free and low-energy dissipation skyrmion based media. 展开更多
关键词 SKYRMIONS magnetic anisotropy micromagnetic simulations
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High-frequency microwave cavity design for high-mass dark matter axion searches
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作者 张驰 王佳 +4 位作者 李春光 陈石广 程航 孙亮 吴云 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期87-94,共8页
The haloscope based on the TM_(010)mode cavity is a well-established technique for detecting QCD axions.However,the method has limitations in detecting high-mass axion due to significant volume loss in the high-freque... The haloscope based on the TM_(010)mode cavity is a well-established technique for detecting QCD axions.However,the method has limitations in detecting high-mass axion due to significant volume loss in the high-frequency cavity.Utilizing a higher-order mode cavity can effectively reduce the volume loss of the high-frequency cavity.The rotatable dielectric pieces as a tuning mechanism can compensate for the degradation of the form factor of the higher-order mode.Nevertheless,the introduction of dielectric causes additional volume loss.To address these issues,this paper proposes a novel design scheme by adding a central metal rod to the higher-order mode cavity tuned by dielectrics,which improves the performance of the haloscope due to the increased effective volume of the cavity detector.The superiority of the novel design is demonstrated by comparing its simulated performance with previous designs.Moreover,the feasibility of the scheme is verified by the full-wave simulation results of the mechanical design model. 展开更多
关键词 AXION haloscope microwave cavity
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Equation of state for boron nitride along the principal Hugoniot to 16 Mbar
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作者 Huan Zhang Yutong Yang +21 位作者 Weimin Yang Zanyang Guan Xiaoxi Duan Mengsheng Yang Yonggang Liu Jingxiang Shen Katarzyna Batani Diluka Singappuli Ke Lan Yongsheng Li Wenyi Huo Hao Liu Yulong Li Dong Yang Sanwei Li Zhebin Wang Jiamin Yang Zongqing Zhao Weiyan Zhang liang sun Wei Kang Dimitri Batani 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第5期77-86,共10页
The thermodynamic properties of boron nitride under extreme pressures and temperatures are of great interest and importance for materials science and inertial confinement fusion physics,but they are poorly understood ... The thermodynamic properties of boron nitride under extreme pressures and temperatures are of great interest and importance for materials science and inertial confinement fusion physics,but they are poorly understood owing to the challenges of performing experiments and realizing ab initio calculations.Here,we report the first shock Hugoniot data on hexagonal boron nitride at pressures of 5–16 Mbar,using hohlraum-driven shock waves at the SGIII-p laser facility in China.Our density functional theory molecular dynamics calculations closely match experimental data,validating the equations of state for modeling the shock response of boron nitride and filling a crucial gap in the knowledge of boron nitride properties in the region of multi-Mbar pressures and eV temperatures.The results presented here provide fundamental insights into boron nitride under the extreme conditions relevant to inertial confinement fusion,hydrogen–boron fusion,and high-energy-density physics. 展开更多
关键词 BORON HUGONIOT EXTREME
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The Impact of Cardiac Pacing Site on Patient's Cardiac Function and Psychological State
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作者 Haiyang Xiao liang sun 《Expert Review of Chinese Medical》 2024年第2期18-22,共5页
With the widespread application of artificial permanent pacemakers in clinical practice,there have been new changes in the indications for pacemaker implantation.The current clinical indications include high atriovent... With the widespread application of artificial permanent pacemakers in clinical practice,there have been new changes in the indications for pacemaker implantation.The current clinical indications include high atrioventricular block,sick sinus syndrome,cardiac resynchronization therapy for heart failure,and implantation of cardioverter defibrillators for ventricular arrhythmias.The implantation of a pacemaker can improve the quality of life and prognosis of patients with arrhythmia.In the past,permanent pacemaker implantation was performed in clinical practice,and the right ventricular pacing electrode was often fixed at the apex of the right ventricle,which belongs to non physiological pacing.Through long-term clinical follow-up,it was found that apex pacing can easily cause abnormal depolarization of the left ventricle,asynchronous contraction of the myocardium,and ultimately lead to myocardial fibrosis,which has adverse effects on the patient's cardiac function and psychological state.In recent years,Scholars have found that pacing in the right ventricular outflow tract septum is closer to the atrioventricular node and closer to the His bundle Purkinje fibers.The pacing impulse almost simultaneously expands towards both ventricles,closer to the physiological pacing state,thereby reducing the occurrence of cardiovascular events in patients.This article explores the impact of pacing in different parts of the heart on the cardiac function and psychological state of patients based on clinical data from the past three years. 展开更多
关键词 pacing site cardiac function psychological state
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PtCo-based nanocatalyst for oxygen reduction reaction:Recent highlights on synthesis strategy and catalytic mechanism
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作者 Wenjuan Yan Puhua sun +6 位作者 Chen Luo Xingfan Xia Zhifei Liu Yuming Zhao Shuxia Zhang liang sun Feng Du 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期101-123,共23页
Oxygen reduction reaction over Pt-based catalyst is one of the most significant cathode reactions in fuel cells.However,low reserves and high price of Pt have motivated researchers worldwide seeking enhanced utilizati... Oxygen reduction reaction over Pt-based catalyst is one of the most significant cathode reactions in fuel cells.However,low reserves and high price of Pt have motivated researchers worldwide seeking enhanced utilization efficiency and durability by doping non-noble metals to form Pt-based alloy catalysts.Alloying Pt with Co has been recognized as one of the most effective approaches to achieve this goal.PtCo bimetal combination is one of the most promising candidates to synthesize highly efficient catalysts for oxygen reduction reaction(ORR)applications,owing to its relatively more suitable oxygen binding energy for four-electron transfer reactions.Recently,impressive strategies have been developed to fabricate more active and stable PtCo-based multimetallic alloys with tailorable size and morphology.This paper aims to summarize the most recent highlights on the study of the relationship between preparation strategies,morphologies,electroactivities of the PtCo-based catalyst at atomic level and further the relevant reaction mechanism.The challenges and opportunities on the further development of electrocatalysts for fuel cells are included to provide reference for the practical application. 展开更多
关键词 ELECTROCHEMISTRY CATALYSIS Oxygen reduction reaction Fuel cells PtCo nanoalloy Multimetallic
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The road toward Cd-safe rice:From mass selection to marker-assisted selection and genetic manipulation
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作者 liang sun Yongjun Tan Caiyan Chen 《The Crop Journal》 SCIE CSCD 2023年第4期1059-1071,共13页
Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessiv... Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessive Cd into the grains,which is a serious threat to agricultural sustainability and human health.To limit Cd accumulation in rice grains,studies on the genetic basis of Cd accumulation in rice have been carried out extensively,and some low-Cd rice varieties have also been developed in recent years.However,the challenges in low-Cd rice breeding still exist because the outcomes of the current genetic improvements for low-Cd rice cannot fully meet the requirements for the development of Cd-safe rice at present.In this review,we outline the progress in understanding the physiological mechanisms and the genetic nature of Cd accumulation in rice and summarize the strategies and outcomes of low-Cd rice breeding over the past decade.By graphing the physiological mechanism of Cd transport in the rice plant,three key steps and some underlying genes are summarized and discussed.Also,two genetic features of the natural variation in rice grain-Cd accumulation,the phenotypic plasticity and subspecies divergence,and the potential genetic explanations for these features are also discussed.Finally,we summarize and discuss current progress and the potential issues in low-Cd rice breeding using different breeding strategies.We hope to propose strategies for future success in the breeding of low-Cd rice varieties over the next decade. 展开更多
关键词 RICE Cadmium-safe Cadmium-free Gene manipulation MAS
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Crystallization Regulation and Morphological Evolution for HTM-free Tin-Lead (1.28eV) Alloyed Perovskite Solar Cells
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作者 Hang Hu Xianyong Zhou +13 位作者 Jiabang Chen Deng Wang Dongyang Li Yulan Huang Luozheng Zhang Yuanjun Peng Feng Wang Jingxia Huang Naichao Chen liang sun Xuesong Liu Xingzhu Wang Jianyong Ouyang Baomin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期113-119,共7页
There have been huge achievements of all-perovskite tandem solar cells,which recently realized the highest power conversion efficiency of 24.8%.However,the complex device structure and complicated manufacture processe... There have been huge achievements of all-perovskite tandem solar cells,which recently realized the highest power conversion efficiency of 24.8%.However,the complex device structure and complicated manufacture processes severely restrict the further development of all-perovskite tandem solar cells.In this work,we successfully fabricated high-efficiency hole transport material-free(HTM-free)Sn−Pb alloyed narrow bandgap perovskite solar cells(PSCs)by introducing guanidinium thiocyanate(GASCN)and hydroiodic acid(HI)into the perovskite precursor solution.GASCN and HI play a positive synergy effect during perovskite crystallization process resulting in larger grain size,fewer surface defects,and lower trap density to suppress the Sn^(2+)oxidation degradation.Furthermore,they could effectively adjust the energy level of perovskite materials,reduce the energy level difference between perovskite and ITO resulting in more efficiently transport of free hole charge carriers.As a result,with adding GASCN and HI,the achieved highest power conversion efficiency of HTM-free devices increased from 12.58%to 17.85%,which is one of the highest PCEs among all values reported to date for the HTM-free narrow-bandgap(1.2-1.4 eV)Sn−Pb binary PSCs.Moreover,the optimized device shows improved environmental stability.Our additive strategy manifests a remarkable step towards the facile,cost-efficient fabrication of HTM-free perovskite-based tandem solar cells with both high efficiency and simple fabrication process. 展开更多
关键词 crystallization regulation hole transport layer-free mixed tin-lead narrow bandgap perovskite solar cells
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Gastric adenosquamous carcinoma with an elevated serum level of alpha-fetoprotein:A case report
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作者 liang sun Juan-Juan Wei +6 位作者 Ran An Hui-Yun Cai Yuan Lv Tao Li Xiao-Fei Shen Jun-Feng Du Gang Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2357-2361,共5页
BACKGROUND Gastric adenosquamous carcinoma(ASC)is rare and characterized by coexisting of adenocarcinoma andsquamous carcinoma within the same tumor.We present a female patient with gastric ASC who had an elevated ser... BACKGROUND Gastric adenosquamous carcinoma(ASC)is rare and characterized by coexisting of adenocarcinoma andsquamous carcinoma within the same tumor.We present a female patient with gastric ASC who had an elevated serum level of alpha-fetopro-tein(AFP),which decreased to normal levels after a laparoscopic distant radical gastrectomy in a short period.The clinicopathological features in AFP-producing gastric cancer(GC)are discussed,as well as potentially available prognostic predi-ctors.CASE SUMMARY A 50-year-old woman presented to our department with a chief complain of a 6-mo history of bloating.She had no basic diseases including heart diseases and respiratory diseases,and she also denied any prior history of dysphagia,hematemesis,melena,rectal bleeding,hematochezia,or unintentional weight loss.Based on her symptoms,an esophagogastroduodenoscopy was performed,showing an annular cavity lesion 3 cm from the pylorus with a diameter of 6 cm.A biopsy of the lesion showed gastric ASC,whereas the pylorus biopsy showed normal mucosa.The patient further received an enhanced computed tomography scan which demonstrated an invasive lesion close to the pylorus with a still clear margin of the tumor to peripheral organs such as the pancreas and liver.Scattered lymph nodes were visible around,whereas no sign of liver metastasis was discovered.Serum tumor markers including carcinoembryonic antigen(CEA),cancer antigen 199(CA199),CA724,CA125,and CA242 were all normal,while the level of serum AFP increased to 172 ng/mL.A laparoscopic distant radical gastrectomy was performed after exclusion of surgical contraindications.Postoperative pathology results showed that the tumor displayed an ulcerated ASC phenotype(90%of medium to highly-differentiated squamous cell carcinoma,10%of poorly differentiated adenocarcinoma.Surprisingly,the serum level of AFP decreased to normal level on post operation day 5.The tumor cells were positive for CK5/6,p63,and CEA,and negative for AFP and Epstein-Barr encoding region.CONCLUSION We presented a rare case of gastric ASC with elevated serum AFP level,which may be new subtype of AFP-producing GC.Follow-up detection of serum AFP might be a useful tool to predict patient prognosis. 展开更多
关键词 Gastric cancer Gastric adenosquamous carcinoma ALPHA-FETOPROTEIN Case report
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水稻锌铁转运蛋白ZIP基因家族研究进展 被引量:18
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作者 孟璐 孙亮 +1 位作者 谭龙涛 储成才 《遗传》 CAS CSCD 北大核心 2018年第1期33-43,共11页
锌(zinc,Zn)和铁(iron,Fe)是水稻(Oryza sativa L.)生长必需的矿质元素,也是人体必需的微量元素。水稻体内Zn、Fe含量维持在适宜水平有利于提高其产量和品质,提高稻米中Zn、Fe含量能够在一定程度上解决人体Zn、Fe营养缺乏的问题。因此,... 锌(zinc,Zn)和铁(iron,Fe)是水稻(Oryza sativa L.)生长必需的矿质元素,也是人体必需的微量元素。水稻体内Zn、Fe含量维持在适宜水平有利于提高其产量和品质,提高稻米中Zn、Fe含量能够在一定程度上解决人体Zn、Fe营养缺乏的问题。因此,研究水稻中Zn和Fe等微量元素转运蛋白的具体功能对于提高水稻产量和稻米品质具有重要意义。锌铁转运蛋白(zinc-regulated transporters and iron-regulated transporter-like protein,ZIP)负责Zn和Fe等离子的吸收、转运和分配,是维持水稻中Zn和Fe平衡的重要转运蛋白,其表达水平受Zn和Fe水平影响。ZIP基因家族在自然群体中具有丰富的等位变异,而且某些单倍型存在明显的籼粳分化,这可能造成了不同品种间籼、粳稻中Zn和Fe积累的差异。目前,已有大量关于ZIP基因家族的研究,但只有Os ZIP3的作用机制研究的较为清楚。另外,对Zn、Fe在籽粒中的积累机制研究和自然群体中ZIP基因的等位变异研究还不够深入。因此,ZIP转运蛋白家族仍存在较大的研究空间。本文详细介绍了ZIP转运蛋白在水稻体内的亚细胞定位、表达模式、转运机制以及在自然群体中的等位变异等,以期为研究水稻稻米微量元素的积累提供理论基础,为提高稻米品质提供借鉴。 展开更多
关键词 ZIP基因 转运机制 自然变异
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission 被引量:11
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin liang sun Junhua Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING PICK-UP MECHANISM TRANSMISSION ratio Non-uniform continuous TRANSMISSION COMBINED NON-CIRCULAR gear TRANSMISSION Optimization design
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The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅱ. design of LST 被引量:6
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作者 Bo Chen Hui Li +47 位作者 Ke-Fei Song Quan-Feng Guo Pei-Jie Zhang Ling-Ping He Shuang Dai Xiao-Dong Wang Hai-Feng Wang Chun-Long Liu Hong-Ji Zhang Guang Zhang Yunqi Wang Shi-Jie Liu Hong-Xin Zhang Lei Liu Shi-Lei Mao Yang Liu Jia-Hao Peng Peng Wang liang sun Yang Liu Zhen-Wei Han Yan-Long Wang Kun Wu Guang-Xing Ding Peng Zhou Xin Zheng Ming-Yi Xia Qing-Wen Wu Jin-Jiang Xie Ya Chen Shu-Mei Song Hong Wang Bo Zhu Chang-Bo Chu Wen-Gang Yang Li Feng Yu Huang Wei-Qun Gan Ying Li Jing-Wei Li Lei Lu Jian-Chao Xue Bei-Li Ying Ming-Zhe sun Cheng Zhu Wei-Min Bao Lei Deng Zeng-Shan Yin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第11期33-48,共16页
As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SD... As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST).When working in-orbit,LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5 R⊙(R⊙stands for the mean solar radius)with a spatial resolution of 4.8′′and 1.2′′for coronal and disk observations,respectively,and a temporal resolution of 30–120 s and 1–120 s for coronal and disk observations,respectively.The maximum exposure time can be up to20 s due to precise pointing and image stabilization function.Among the three telescopes of LST,SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Lyα(121.6±10 nm)line and white light(WL)(700±40 nm)wavebands by using a narrowband Lyαbeam splitter and has a field of view(FOV)from 1.1 to 2.5 R⊙.The stray-light suppression level can attain<10^-6 B⊙(B⊙is the mean brightness of the solar disk)at 1.1 R⊙and≤5×10^-8 B⊙at 2.5 R⊙.SDI and WST are solar disk imagers working in the Lyαline and 360.0 nm wavebands,respectively,which adopt an off-axis two-mirror reflective structure with an FOV up to 1.2 R⊙,covering the inner coronal edge area and relating to coronal imaging.We present the up-to-date design for the LST payload. 展开更多
关键词 telescopes—instrumentation high angular resolution—Sun flares—Sun CORONAL mass ejections(CMEs)—Sun UV radiation
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Identification and characterization of genes that control fat deposition in chickens 被引量:10
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作者 Hirwa Claire D'Andre Wallace Paul +4 位作者 Xu Shen Xinzheng Jia Rong Zhang liang sun Xiquan Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第1期22-37,共16页
Background: Fat deposits in chickens contribute significantly to meat quality attributes such as juiciness, flavor, taste and other organoleptic properties. The quantity of fat deposited increases faster and earlier ... Background: Fat deposits in chickens contribute significantly to meat quality attributes such as juiciness, flavor, taste and other organoleptic properties. The quantity of fat deposited increases faster and earlier in the fast- growing chickens than in slow-growing chickens. In this study, Affymetrix Genechip~ Chicken Genome Arrays 32773 transcripts were used to compare gene expression profiles in liver and hypothalamus tissues of fast-growing and slow-growing chicken at 8 wk of age. Real-time RT-PCR was used to validate the differential expression of genes selected from the microarray analysis. The mRNA expression of the genes was further examined in fat tissues. The association of single nucleotide polymorphisms of four lipid-related genes with fat traits was examined in a F2 resource population. Results: Four hundred genes in the liver tissues and 220 genes hypothalamus tissues, respectively, were identified to be differentially expressed in fast-growing chickens and slow-growing chickens. Expression levels of genes for lipid metabolism (SULTIB1, ACSBG2, PNPLA3, LPL, AOAH) carbohydrate metabolism (MGAT4B, XYLB, GBE1, PGM1, HKDCl)cholesttrol biosynthesis (FDPS, LSS, HMGCR, NSDHL, DHCR24, IDI1, MEI) HSD17B7 and other reaction or pro- cesses (CYPIA4, CYP1A1, AKR1BI, CYP4V2, DDO) were higher in the fast-growing White Recessive Rock chickens than in the slow-growing Xinghua chickens. On the other hand, expression levels of genes associated with multicellular organism development, immune response, DNA integration, melanin biosynthetic process, muscle organ develop- ment and oxidation-reduction (FRZB, DMD, FUT8, CYP2C45, DHRSX, and CYP2C18) and with glycol-metabolism (GCNT2, ELOVL d, and FASN), were higher in the XH chickens than in the fast-growing chickens, fiT-PCR validated high expression levels of nine out of 12 genes in fat tissues. The G1257069A and T1247123C of the ACSBG2 gene were significantly associated with abdominal fat weight. The G4928024A of the FASN gene were significantly associ- ated with fat bandwidth, and abdominal fat percentage. The C4930169T of the FASN gene was associated with ab- dominal fat weight while the A59539099G of the ELOVL 6 was significantly associated with subcutaneous fat. The A8378815G of the DDT was associated with fat band width. Conclusion: The differences in fat deposition were reflected with differential gene expressions in fast and slow growing chickens. 展开更多
关键词 CHICKEN Fat deposition GENES
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Proteinase-activated receptor 2 promotes tumor cell proliferation and metastasis by inducing epithelialmesenchymal transition and predicts poor prognosis in hepatocellular carcinoma 被引量:4
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作者 liang sun Pi-Bao Li +4 位作者 Yan-Fen Yao Ai-Yuan Xiu Zhi Peng Yu-Huan Bai Yan-Jing Gao 《World Journal of Gastroenterology》 SCIE CAS 2018年第10期1120-1133,共14页
AIM To clarify the role of proteinase-activated receptor 2(PAR2) in hepatocellular carcinoma, especially in the process of metastasis.METHODS PAR2 expression levels were assessed by qRT-PCR and immunohistochemistry(IH... AIM To clarify the role of proteinase-activated receptor 2(PAR2) in hepatocellular carcinoma, especially in the process of metastasis.METHODS PAR2 expression levels were assessed by qRT-PCR and immunohistochemistry(IHC) in patient tissues and in hepatocellular carcinoma cell lines SMMC-7721 and Hep G2. Cell proliferation and metastasis were assessed both in vitro and in vitro. Immunoblotting was carried out to monitor the levels of mitogen-activated protein kinase(MAPK) and epithelial-mesenchymal transition markers.RESULTS The prognosis was significantly poorer in patients with high PAR2 levels than in those with low PAR2 levels. Patients with high PAR2 levels had advanced tumor stage(P = 0.001, chi-square test), larger tumor size(P = 0.032, chi-square test), and high microvascular invasion rate(P = 0.037, chi-square test). The proliferation and metastasis ability of SMMC-7721 and Hep G2 cells was increased after PAR2 overexpression, while knockdown of PAR2 decreased the proliferation and metastasis ability of SMMC-7721 and Hep G2 cells. Knockdown of PAR2 also inhibited hepatocellular carcinoma tumor cell growth and liver metastasis in nude mice. Mechanistically, PAR2 increased the proliferation ability of SMMC-7721 and Hep G2 cells via ERK activation. Activated ERK further promoted the epithelial-mesenchymal transition of these cells, which endowed them with enhanced migration and invasion ability. CONCLUSION These data suggest that PAR2 plays an important role in the proliferation and metastasis of hepatocellular carcinoma. Therefore, targeting PAR2 may present a favorable target for treatment of this malignancy. 展开更多
关键词 HEPATOCELLULAR carcinoma Proteinaseactivated receptor 2 Epithelial-mesenchymal transition
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Clonal Selection Based Memetic Algorithm for Job Shop Scheduling Problems 被引量:4
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作者 Jin-hui Yang liang sun +2 位作者 Heow Pueh Lee Yun Qian Yan-chun liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第2期111-119,共9页
A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exp... A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exploration and exploitation. In the clonal selection mechanism, clonal selection, hypermutation and receptor edit theories are presented to construct an evolutionary searching mechanism which is used for exploration. In the local search mechanism, a simulated annealing local search algorithm based on Nowicki and Smutnicki's neighborhood is presented to exploit local optima. The proposed algorithm is examined using some well-known benchmark problems. Numerical results validate the effectiveness of the proposed algorithm. 展开更多
关键词 job shop scheduling problem clonal selection algorithm simulated annealing global search local search
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Saturated Adaptive Output-Constrained Control of Cooperative Spacecraft Rendezvous and Docking 被引量:3
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作者 liang sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1462-1470,共9页
This paper investigates the robust relative pose control for spacecraft rendezvous and docking with constrained relative pose and saturated control inputs.A barrier Lyapunov function is used to ensure the constraints ... This paper investigates the robust relative pose control for spacecraft rendezvous and docking with constrained relative pose and saturated control inputs.A barrier Lyapunov function is used to ensure the constraints of states,so that the computational singularity of the inverse matrix in control command can be avoided,while a linear auxiliary system is introduced to handle with the adverse effect of actuator saturation.The tuning rules for designing parameters in control command and auxiliary system are derived based on the stability analysis of the closed-loop system.It is proved that all closed-loop signals always keep bounded,the prescribed constraints of relative pose tracking errors are never violated,and the pose tracking errors ultimately converge to small neighborhoods of zero.Simulation experiments validate the performance of the proposed robust saturated control strategy. 展开更多
关键词 Output-constrained CONTROL POSE tracking CONTROL RENDEZVOUS and DOCKING saturated CONTROL singularity-free CONTROL SPACECRAFT CONTROL
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Modified methods for culturing myoblasts of rats: Combination of multi-enzymatic digestion and double purification 被引量:3
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作者 Li Zhang Wei Wang +3 位作者 Ming Fan Xiaoping Chen Shuhong Liu liang sun 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第1期1-5,共5页
BACKGROUND: With developments of tissue engineering and genetic engineering, we aim to culture myoblasts, which are characterized by high purity, high quality and high production, for wide application in neural regen... BACKGROUND: With developments of tissue engineering and genetic engineering, we aim to culture myoblasts, which are characterized by high purity, high quality and high production, for wide application in neural regeneration researches. OBJECTIVE: To modify traditional dissociation method in order to obtain myoblasts, which are characterized by high purity, high quality and high production, and explore the biological properties under in vitro culture. DESIGN: Observational study. SETTING: Basic Institute of Academy of Military Medical Sciences of Chinese PLA. MATERIALS: Four neonatal Wistar rats of 5 days old, both genders and mean body mass of 10 g were selected in this study. The main reagents and devices were detailed as follows: DMEM medium (Gibco Company), fetus bovine serum (FBS, Hycolne Company), collagenase Ⅱ (Sigma Company), trypsin (Sigma Company), dispase Ⅱ (Sigma Company), desmin antibody (Fuzhou Maixin Company), antibody Ⅱ and ABC kit (Wuhan Baster Biotechnology Company), desk centrifuge (KUBATO, Japan), and inverted phase contrast microscope (LEICA DMIRB, Germany). METHODS: The experiment was carried out in the Basic Institute of Academy of Military Medical Sciences of Chinese PLA from June to October 2006. Neonatal rats were sacrificed under sterile condition to obtain skeletal muscles of limbs, which were washed with cold PBS (containing benzylpenicillin and estreptomicina), and muscular tissue was sheared into pieces. Then, those muscular pieces were added with mixed digestive enzyme (containing 2 g/L collagenase Ⅱ + 5 g/L dispase Ⅱ + 0.28 g/L CaCl2) as twice volume as pieces, dealt with mechanical pipetting for 5 minutes and cultured in CO2 incubator for 10 minutes. The operation was done for three times and the muscular pieces were digested for 45 minutes in total. Moreover, cells were suspended again in order to obtain myoblasts from skeletal muscle of neonatal rats. In addition, myoblasts were purified with differential attachment technique and enzyme digestion so as to observe morphological characteristics and growth, draw growth curve, analyze surface structure under scanning electron microscope, and evaluate with Desmin immunohistochemical staining. MAIN OUTCOME MEASURES: Morphological characteristics and growth ofmyoblasts cultured in vitro. RESULTS: ①Growth of myoblasts of skeletal muscle: Primary cells had well growth, mature and differentiation. The positive rate of Desmin was 94% and purification of cells was ideal. Growth curve of cells demonstrated that myoblasts which were characterized by high purification started proliferation plentiful through transient growth lag phase (about at one or two days after inoculation). If myoblasts were not dealt with any interventions, they might become sarcotubule gradually at 3 - 5 days after proliferative phase. During this period, myoblasts maintained a monocaryon-bipolarity state under inverted phase contrast microscope. Furthermore, the growth of cells was the strongest and reproductive activity was the most powerful. This suggested that myotube started to form; in addition, muscle fiber of contractility might form under a well culturing condition. ②Immunocytochemical stain with desmin antibody: Interzonal fiber of desmin from myoblasts showed strongly positive reaction. Positive staining existed in cytoplasm had a high nucleus-cytoplasm ratio. However, myoblasts showed negative or mildly positive reaction. CONCLUSION: It is ideal for modified multi-enzymatic digestion and double purification method to dissociate and purify myoblasts of skeletal muscle; meanwhile, these two methods are both the effective ways to provide convenient conditions to obtain seed cells for neural regeneration researches. 展开更多
关键词 myoblast cell skeletal muscle cellular transplantation IMMUNOHISTOCHEMISTRY
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Density-dependent shock Hugoniot of polycrystalline diamond at pressures relevant to ICF 被引量:4
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作者 Peng Wang Chen Zhang +9 位作者 Shaoen Jiang Xiaoxi Duan Huan Zhang LiLing Li Weiming Yang Yonggang Liu Yulong Li liang sun Hao Liu Zhebin Wang 《Matter and Radiation at Extremes》 SCIE CAS CSCD 2021年第3期33-41,共9页
In inertial confinement fusion(ICF),polycrystalline diamond-referred to as high density carbon(HDC)-has become a promising ablator candidate.However,with smaller grain size and lower initial density,the equation of st... In inertial confinement fusion(ICF),polycrystalline diamond-referred to as high density carbon(HDC)-has become a promising ablator candidate.However,with smaller grain size and lower initial density,the equation of state(EOS)for HDC can deviate from that for single-crystal diamond,which could be a concern for ICF designs,but current experimental EOS studies for HDC are far from sufficient to clarify how initial density affects target compressibility.Presented here are measurements of the Hugoniot for HDC with an initial density of 3.23 g/cm^(3) at pressures of 17–26 Mbar.Combined with experimental data reported for nanocrystalline diamond(NCD),a stiffer compressibility of NCD due to lower initial density is confirmed.Two porous models are used for comparison and seem to offer better agreement compared with SESAME databases.Also,the effect of temperature on the Gruneisen parameter,which is usually neglected,might need to be considered for NCD under these conditions.The present data offer important support for EOS studies relevant to ICF and constrain the construction of wide-range EOS. 展开更多
关键词 conditions. POLYCRYSTALLINE NEGLECTED
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