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Rapidly counting atomic planes of ultra-thin MoSe2 nanosheets(1≤n≤4)on SiO2/Si substrate

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Rare Metals 2016年第8期35卷 632-636页

作者： Yi-Ping Wang Hui-Jun Zhou Gui-hua Zhao Tian-long Xia Lei Wang Le Wang li-Yuan Zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-electronic Functional Materialsand Micro-nano Devices Renmin University of China Department of Power and Electrical Engineering Northwest A&F UniversityYangling 712100ShaanxiChina

The optical, thermal and electrical properties of ultra-thin two-dimensional （2D） crystal materials are highly related to their thickness. Therefore, identifying the atomic planes of few-layer crystal materials rapidly is crucial to fundamental study. Here, a simple technique was demonstrated based on optical contrast for counting atomic planes （n） of few-layer MoSe2 on SiO2/Si substrates. It is found that the optical contrast of single-layer MoSe2 depends on light wavelength and thickness of SiO2 on Si substrate. The data calculated based on a Fresnel law-based model as well as atomic force microscopy （AFM） mea- surements fit well with the values measured by spectro- scopic ellipsometer. Furthermore, the calculated and measured contrasts were integral and plotted, which can be used to determine the MoSe2 atomic planes （1 ≤ n ≤ 4） accurately and rapidly.

关键词： Thickness identification Optical contrast MoSe2 Optical microscopy

调卫和营宣痹方辅助干预冠心病PCI术后再发心绞痛的临床疗效观察

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广州中医药大学学报 2024年第8期41卷 2009-2015页

作者：吴健程珍陈智龙吴正国黄石市中医医院湖北黄石435000

【目的】观察调卫和营宣痹方与常规西药联合治疗对冠心病经皮冠状动脉介入(PCI)术后再发心绞痛的治疗效果。【方法】将90例冠心病PCI术后再发心绞痛寒凝心脉证患者随机分为对照组和治疗组,每组各45例。对照组给予常规西药治疗,治疗组在... 详细信息

【目的】观察调卫和营宣痹方与常规西药联合治疗对冠心病经皮冠状动脉介入(PCI)术后再发心绞痛的治疗效果。【方法】将90例冠心病PCI术后再发心绞痛寒凝心脉证患者随机分为对照组和治疗组,每组各45例。对照组给予常规西药治疗,治疗组在对照组的基础上联合调卫和营宣痹方治疗,疗程为12周。观察2组患者治疗前后中医证候积分、心绞痛疗效积分、西雅图心绞痛量表(SAQ)评分以及左心室射血分数(LVEF)、室间隔厚度(IVS)的变化情况,并评定2组患者的临床疗效和用药安全性。【结果】(1)脱落情况方面,研究过程中,对照组和治疗组各有1例患者脱落,最终对照组和治疗组各有44例患者纳入疗效统计。(2)疗效方面,治疗12周后,治疗组的总有效率为93.18%(41/44),对照组为81.82%(36/44),组间比较(χ2检验),治疗组的疗效明显优于对照组(P0.05);治疗后组间比较,治疗组的LVEF改善幅度明显优于对照组(P0.05);且2组患者的血、尿、大便常规及肝功能、肾功能、心电图等安全性指标均无明显变化。【结论】在常规西药治疗基础上联合调卫和营宣痹方治疗,能有效缓解冠心病PCI术后再发心绞痛寒凝心脉证患者的临床症状,改善患者的中医证候及左心室射血分数,临床疗效显著。

关键词：冠心病经皮冠状动脉介入(PCI)术后心绞痛寒凝心脉证调卫和营宣痹方左心室射血分数(LVEF)

干旱对森林生态系统结构及功能的影响研究进展

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世界林业研究 2024年第4期37卷 37-45页

作者：吴诗婷王国兵杨立青刘帅南京林业大学生态与环境学院南京210037

全球气候变化导致的干旱对森林生态系统结构和功能的影响已成为学术界和环境保护领域的关注焦点。文中通过综合分析现有研究文献,总结了全球气候变化下干旱对森林生态系统结构与功能的影响。目前的研究发现,干旱能够引起森林生物地球化... 详细信息

全球气候变化导致的干旱对森林生态系统结构和功能的影响已成为学术界和环境保护领域的关注焦点。文中通过综合分析现有研究文献,总结了全球气候变化下干旱对森林生态系统结构与功能的影响。目前的研究发现,干旱能够引起森林生物地球化学循环减弱、森林火灾频率增加、物种组成和生物多样性损失、森林抵抗力和恢复力减弱以及森林生产力和稳定性下降等现象。对此,需要通过长期观测、延长控制实验时间、模拟原生环境条件等开展多因素综合实验,进一步探究地上—地下耦合过程对干旱的反馈调节机制以及森林植被对于干旱胁迫的生物调节机制,为进一步理解干旱对森林生态系统的影响以及制定干旱条件下森林经营管理对策提供理论参考。

关键词：干旱森林结构森林功能物种组成生物多样性生物地球化学循环森林生产力稳定性

Effect of ion-beam assisted deposition on the film stresses of TiO_2 and SiO_2 and stress control

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Acta Mechanica Sinica 2012年第5期28卷 1382-1388页

作者： Yu-Qiong li hua-Qing Wang wu-Yu Wang Zhi-Nong Yu He-Shan liu Gang Jin National Microgravity Laboratory(NML) Institute of MechanicsChinese Academy of Sciences School of Optoelectronics Beijing Institute of Technology Optical Thin Film Center Daheng New Epoch Technology Inc. Beijing General Research Institute for Nonferrous Metals Division of Mineral Research and Material Energy

Based on Hartmann-Shack sensor technique, an online thin film stress measuring system was introduced to measure the film stresses of TiO2 and SiO2, and comparison was made between the film stresses prepared respectively by the conventional process and the ion-beam assisted deposition. The effect of ion-beam assisted deposition on the film stresses of TiO2 and SiO2 was investigated in details, and the stress control methodologies using on-line adjustment and film doping were put forward. The results show that the film stress value of TiO2 prepared by ion-beam assisted deposition is 40 MPa lower than that prepared by conventional process, and the stress of TiO2 film changes gradually from tensile stress into compressive stress with increasing ion energy; while the film stress of SiO2 is a tensile stress under ion-beam assisted deposition because of the ion-beam sputtering effect, and the film refractive index decreases with increasing ion energy. A dynamic film stress control can be achieved through in-situ adjustment of the processing parameters based on the online film stress measuring technique, and the intrinsic stress of film can be effectively changed through film doping.

关键词： Film stress Stress controlling Ion-beam as-sisted deposition Hartmann-Shack sensor

Cloning and Characterization of karmoisin Homologue Gene(Nlka) in Two Brown Planthopper Strains with Different Eye Colors

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Rice science 2016年第2期23卷 104-110页

作者： liU Shu-hua TANG Jian LUO Ju yang Bao-jun WANG Ai-ying wu Jin-cai School of Plant Protection Yangzhou University State Key Laboratory of Rice Biology China National Rice Research Institute

The brown planthopper （BPH）, Nilaparvata lugens, is a destructive insect pest of rice throughout Asia. Different from brown-eye color wild type, BPH also has red-eye color mutation phenotype. As a visible genetic marker, the red-eye mutant in BPH is a valuable material. To reveal the eye color mutation mechanism, a karmoisin homologue gene （named as Nlka） was cloned from BPH. And karmoisin is always deemd as a xanthommatin-related gene in other insects, encoding phenoxazinone synthetase （PHS）. Nlka is consisted of 7 exons and encodes a protein with 502 amino acids （NIKA）. NIKA showed high amino acid identities with its insect homologues （48.8%-51.8%）. Nlka transcripts can be detected at all the developmental stages and in all tissues tested, including egg, nymph, adult, body wall, ovary, fat body, midgut and Malpighian tubule. However, no constant In/Del or non-synonymous mutation was observed between the mutant and the wild type strains. Quantitative real-time PCR experiment also showed that Nlka transcript level had no significant differences between them. These results indicated that Nlka is not the target gene causing the red-eye color mutation phenotype of BPH. Through the second structure and motif analysis, the present study also showed that all the proteins deduced from the karmoisin genes in insects may be members of monocarboxylate transporters （MCTs） rather than PHSs.

关键词： Nilaparvata lugens red-eye mutant karmoisin monocarboxylate transporter phenoxazinone synthetase rice gene clone

Genomic consequences of population decline in critically endangered pangolins and their demographic histories

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National Science Review 2020年第4期7卷 798-814页

作者： Jing-yang Hu Zi-Qian Hao Laurent Frantz Shi-Fang wu wu Chen Yun-Fang Jiang Hong wu Wei-Min Kuang Haipeng li Ya-Ping Zhang li Yu State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan School of Life Sciences Yunnan University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming College of life Science University of Chinese Academy of Sciences CAS Key Laboratory of Computational Biology CAS-MPG Partner Institute for Computational Biology Shanghai Institute of Nutrition and Health Chinese Academy of Sciences University of Chinese Academy of Sciences School of Biological and Chemical Sciences Queen Mary University of London The Palaeogenomics and Bio-Archaeology Research Network Department of Archaeology University of Oxford Guangzhou Zoo Lushui Management and Conservation Branch of Gaoligong Mountain National Nature Reserve Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

Pangolins are among the most critically endangered animals due to heavy poaching and worldwide trafficking. However, their demographic histories and the genomic consequences of their recent population declines remain unknown. We generated high-quality de novo reference genomes for critically endangered Malayan(Manis javanica, MJ) and Chinese(M. pentadactyla, MP) pangolins and re-sequencing population genomic data from 74 MJs and 23 MPs. We recovered the population identities of illegally traded pangolins and previously unrecognized genetic populations that should be protected as evolutionarily distinct conservation units. Demographic reconstruction suggested environmental changes have resulted in a population size fluctuation of pangolins. Additionally, recent population size declines due to human activities have resulted in an increase in inbreeding and genetic load. Deleterious mutations were enriched in genes related to cancer/diseases and cholesterol homeostasis, which may have increased their susceptibility to diseases and decreased their survival potential to adapt to environmental changes and high-cholesterol diets. This comprehensive study provides not only high-quality pangolin reference genomes, but also valuable information concerning the driving factors of long-term population size fluctuations and the genomic impact of recent population size declines due to human activities, which is essential for pangolin conservation management and global action planning.

关键词： pangolins population genomics population declines genetic diversity inbreeding genetic load demographic history

A dynamic constitutive model of ultra high toughness cementitious composites

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第12期21卷 939-960页

作者： Shi-lang XU Ping wu Fei ZHOU xiao JIANG Bo-kun CHEN Qing-hua li Institute of Advanced Engineering Structures and Materials Zhejiang UniversityHangzhou 310058China

In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive damage evolution,hydrostatic pressure,strain rate,and the Lode angle *** proposed model was embedded in LS-DYNA software and then comprehensive tests were carried on a hexahedral brick element formulation under uniaxial,biaxial,and triaxial stress states to verify its rationality through comparisons with results determined by the HJC and Karagozian&Case(K&C)***,the proposed model was used to simulate the damage caused to UHTCC targets subjected to blast by embedded explosive and projectile penetration,and predictions were compared with corresponding experimental *** results of the numerical simulations showed that our proposed model was more accurate than the HJC model in predicting the size of the crater,penetration depth,and the distribution of cracks inside the target following the blast or high-speed impact loading.

关键词： Holmquist–Johnson–Cook(HJC)model Ultra high toughness cementitious composite(UHTCC) Constitutive model Explosion test Projectile penetration Numerical simulation

Serum chitinase-3-like protein 1 is a biomarker of liver fibrosis in patients with chronic hepatitis B in China

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 384-389页

作者： Xin Jin Bin Fu Zheng-Jie wu xiao-Qin Zheng Jian-hua Hu lin-Feng Jin ling-ling Tang State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China College of Medicine Shaoxing UniversityShaoxing 312000China Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022China

Background:Serum chitinase-3-like protein 1(CHI3L1)is a potential biomarker for fibrosis *** aimed to evaluate serum CHI3L1 as a noninvasive diagnostic marker for chronic hepatitis B virusrelated ***:Serum CHI3L1 levels were measured by EliSA in 134 chronic hepatitis B(CHB)*** fibrosis was defined as a liver stiffness>9.7 *** performance of CHI3L1 was assessed and compared to that of other noninvasive tests by receiver operating characteristic(ROC)***:Serum CHI3L1 levels were significantly higher in CHB patients with significant hepatic fibrosis(≥F2)than in those without significant hepatic fibrosis(liver ***,CHI3L1 is feasible in monitoring disease progression.

关键词： Chitinase-3-like protein 1 Hepatitis B virus Noninvasive liver stiffness Significant fibrosis

Stellar parameters of main sequence turn-off star candidates observed with LAMOST and Kepler

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Research in Astronomy and Astrophysics 2017年第1期17卷 55-70页

作者： Ya-Qian wu Mao-Sheng Xiang Xian-Fei Zhang Tan-Da li Shao-Lan Bi xiao-Wei liu Jian-Ning Fu yang huang Zhi-Jia Tian Kang liu Zhi-Shuai Ge Xin He Jing-hua Zhang Department of Astronomy Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University

Main sequence turn-off （MSTO） stars since their ages can be robustly estimated from have advantages as indicators of Galactic evolution atmospheric parameters. Hundreds of thousands of MSTO stars have been selected from the LAMOST Galactic survey to study the evolution of the Galaxy, and it is vital to derive accurate stellar parameters. In this work, we select 150 MSTO star candidates from the MSTO star sample of Xiang that have asteroseismic parameters and determine accurate stellar parameters for these stars by combining asteroseismic parameters deduced from Kepler photometry and atmospheric parameters deduced from LAMOST spectra. With this sample, we examine the age determination as well as the contamination rate of the MSTO star sample. A comparison of age between this work and Xiang shows a mean difference of 0.53 Gyr （7%） and a dispersion of 2.71 Gyr （28%）. The results show that 79 of the candidates are MSTO stars, while the others are contaminations from either main sequence or sub-giant stars. The contamination rate for the oldest stars is much higher than that for younger stars. The main cause for the high contamination rate is found to be the relatively large systematic bias in the LAMOST surface gravity estimates.

关键词： stars: fundamental parameters - stars evolution - stars asteroseismology