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Driving force and changing trends of vegetation phenology in the Loess Plateau of China from 2000 to 2010

Journal of Mountain Science 2016年第5期13卷 844-856页

作者： wang hao LIU Guo-hua LI Zong-shan YE Xin wang meng GONG Li State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental ScienceChinese Academyof SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Changes in vegetation phenology are key indicators of the response of ecosystems to climate ***,knowledge of growing seasons is essential to predict ecosystem changes,especially for regions with a fragile ecosystem such as the Loess *** this study,based on the normalized difference vegetation index(NDVI) data,we estimated and analyzed the vegetation phenology in the Loess Plateau from 2000 to 2010 for the beginning,length,and end of the growing season,measuring changes in trends and their relationship to climatic *** results show that for 54.84% of the vegetation,the trend was an advancement of the beginning of the growing season(BGS),while for 67.64% the trend was a delay in the end of the growing season(EGS).The length of the growing season(LGS) was extended for 66.28% of the vegetation in the *** the temperature is important for the vegetation to begin the growing season in this region,warmer climate may lead to drought and can become a limiting factor for vegetation *** found that increasedprecipitation benefits the advancement of the BGS in this *** with a delayed EGS indicated that the appropriate temperature and rainfall in autumn or winter enhanced photosynthesis and extended the growth process.A positive correlation with precipitation was found for 76.53% of the areas with an extended LGS,indicating that precipitation is one of the key factors in changes in the vegetation phenology in this water-limited *** plays an important role in determining the phenological activities of the vegetation in arid and semiarid areas,such as the Loess *** extended growing season will significantly influence both the vegetation productivity and the carbon fixation capacity in this region.

关键词： The Loess Plateau Trend analysis Phenology NDVI Vegetation green-up date

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Precipitation Behavior of Nb in Steel under Ultra Fast Cooling Conditions

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 375-379页

作者：周晓光 wang meng LIU Zhenyu YANG hao WU Di wang Guodong The State Key Laboratory of Rolling Technology and Automation Northeastern University

By measuring the expansion curves of a Nb bearing steel at different cooling rates by using Gleeble-3800 thermomechanical simulator, combining with metallographic analysis, different phase zones were determined. Also, precipitation behavior of Nb at different phase zones was investigated under ultra fast cooling conditions. The experimental results showed that adopting a proper deformation temperature, the ultra fast cooling process can restrain the precipitation of Nb at austenite phase zone. More quantities and smaller size precipitates of Nb can be found at the ferrite or bainite phase zone by controlling the ultra fast cooling ending temperature. With the increase of holding time at austenite, ferrite and bainite phase zones respectively, the volume fraction of precipitation, density, and average size of precipitates will increase obviously. With the decrease of early ultra fast cooling ending temperature, the density of Nb precipitates first increase（at ferrite phase zone） and then decrease（at bainite phase zone）, the volume fraction of Nb precipitation decreases and precipitates can be refined. The optimal early ultra fast cooling ending temperature is located at ferrite phase zone. The combination of high rolling temperature with early ultra fast cooling technology opens the way for new cooling schedules and makes the production of high strength steels easier and cheaper by making full use of Nb precipitation strengthening effect.

关键词： Nb bearing steel precipitation ultra fast cooling microstructure

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Dissecting aneurysm of the inter-atrial and inter-ventricular septum with concomitant ventricular septal defect multi-modality cardiac imaging and surgical repair

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中国循环杂志 2016年第Z1期31卷 -页

作者： Jinping Zhang Hong meng hao wang Department of Echocardiography FuwaiHospital NationalCenter for Cardiovascular Disease Chinese Academy of Medical Sciences and Peking Union MedicalColege Beijing China

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Study on growing thick AlGaN layer on c-plane sapphire substrate and free-standing GaN substrate

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Science China(Physics,Mechanics & Astronomy) 2012年第12期55卷 2383-2388页

作者： wang DangHui ZHOU hao ZHANG JinCheng XU ShengRui ZHANG LinXia meng FanNa AI Shan hao Yue State Key Lab.of Fundamental Science on Wide Band-Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi'an 710071China School of Materials Science and Engineering of Xi'an ShiYou University Xi'an 710065China

In this study,the thick AlGaN epilayers have been grown on the c-plane sapphire substrate and the free-standing GaN substrate using low-temperature AlN nucleation layers by low-pressure metal-organic chemical vapor deposition(LPMOCVD).High resolution X-ray diffraction(HRXRD),atom force microscopy(AFM),scanning electron microscopy(SEM),photoluminescence(PL) and Raman scattering measurements have been employed to study the crystal quality,threading dislocation density,surface morphology,optical properties and phonon properties of thick AlGaN *** results indicate that AlGaN epifilms crystal quality can be improved greatly when grown on the free-standing GaN *** calculated the threading dislocation density and found that thick AlGaN epifilm grown on the free-standing GaN substrate is much lower in total threading dislocation density than that grown on the sapphire substrate,although the surface morphology is rougher than that of sapphire substrate.

关键词： metal-organic chemical vapor deposition crystal quality surface morphology AlN nucleation layer

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Surgical strategy used in multilevel cervical disc replacement and cervical hybrid surgery:Four case reports

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World Journal of Clinical Cases 2020年第17期8卷 3890-3902页

作者： Xiao-Fei wang Yang meng hao Liu Ying Hong Bei-Yu wang Department of Orthopaedic Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Operation Room West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Multilevel artificial cervical disc replacement and anterior hybrid surgery have been introduced as reliable treatments for multilevel cervical degenerative disc *** techniques are important for resolving patients’symptoms and maintaining the normal functioning of cervical ***,the use of inappropriate surgical strategies could lead to complications such as implant migration and neurological *** this paper,we summarize our surgical strategies used in multilevel cervical disc replacement and hybrid surgery into five major *** SUMMARY We share the key notes and our surgical procedures in the form of four typical case *** patients were diagnosed with cervical degenerative disc disease with myelopathy or radiculopathy and needed multilevel cervical spine *** first case demonstrated that index levels indicating the presence of highly serious spinal cord compression required a prioritized *** second case demonstrated that the disc replacement should be performed before fusion in cervical hybrid *** third and forth cases demonstrated that a top-down implantation sequence was needed in continuous two-level cervical disc *** symptoms of all patients were significantly relieved after *** We hope that our surgical strategies can help improve the performance and outcomes of multilevel cervical spine surgery.

关键词： Cervical disc replacement Cervical hybrid surgery Multilevel cervical spine surgery Surgical strategy Implant migration Case report

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The mini-QSO's contribution to cosmic reionization

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Research in Astronomy and Astrophysics 2010年第3期10卷 199-210页

作者： Ying-Ying wang Lei wang Shou-Ping Xiang Yu wang Jing-meng hao Ye-Fei Yuan Center for Astrophysics University of Science and Technology of China Hefei 230026 China Shanghai Astronomical Observatory Joint Institute for Galaxy and Cosmology （JOINGC） of SHAO and USTC Shanghai 200030 China

By employing an improved simulation of the evolution of black holes （BHs） based on the merger tree of dark matter halos, we explore the relationship between the central BH mass Mbh and velocity dispersion σ＊ at high redshift z ≥ 6 and quantify the mini-QSO＇s （with BH mass M = 200 - 105M⊙） contribution to cosmic reionization. The simulation demonstrates how seed BHs migrate onto the MBH-σ＊ relation by merging with each other and accreting gas at z ≥ 6： 1. The correlation between BHs and their host halos increases as the BHs grow; 2. The slope, i.e. Ф = dlog（Mbh）/dlog（σ＊） in the relationship, is insensitive to the redshift at z 〉 6. In agreement with previous work, we find that mini-QSOs＇ ionizing capability to the Universe lies in the range - 25% - 50% if early miniquasars have extremely high duty cycles, i.e. P（z 〉 6） - 0.9 - 1.

关键词： cosmology: theory -- galaxies: evolution

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A 10 bit 200 MS/s pipeline ADC using loading-balanced architecture in 0.18 μm CMOS

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Journal of Semiconductors 2017年第7期38卷 103-110页

作者： Linfeng wang Qiao meng hao Zhi Fei Li Institute of RF- & OE-ICs Southeast University Nanjing 210096 China

A new loading-balanced architecture for high speed and low power consumption pipeline analog-todigital converter（ADC） is presented in this paper. The proposed ADC uses SHA-less, op-amp and capacitor-sharing technique, capacitor-scaling scheme to reduce the die area and power consumption. A new capacitor-sharing scheme was proposed to cancel the extra reset phase of the feedback capacitors. The non-standard inter-stage gain increases the feedback factor of the first stage and makes it equal to the second stage, by which, the load capacitor of op-amp shared by the first and second stages is balanced. As for the fourth stage, the capacitor and op-amp no longer scale down. From the system＇s point of view, all load capacitors of the shared OTAs are balanced by employing a loadingbalanced architecture. The die area and power consumption are optimized maximally. The ADC is implemented in a 0.18 μm 1P6M CMOS technology, and occupies a die area of 1.2×1.2 mm^2. The measurement results show a 55.58 dB signal-to-noise-and-distortion ratio（SNDR） and 62.97 dB spurious-free dynamic range（SFDR） with a 25 MHz input operating at a 200 MS/s sampling rate. The proposed ADC consumes 115 m W at 200 MS/s from a 1.8 V supply.

关键词： pipeline ADC loading-balanced op-amp sharing SHA-Less MDAC scaling down

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Power losses caused by longitudinal HOMs in 1.3-GHz cryomodule of SHINE

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Nuclear Science and Techniques 2019年第7期30卷 16-26页

作者： Jun-Jie Guo Qiang Gu meng Zhang Zhen wang Jian-hao Tan Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201210 China

Shanghai high-repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. In this paper, power losses caused by trapped longitudinal high-order modes (HOM), steady-state loss, and transient loss generated by untrapped HOMs in the 1.3-GHz SHINE cryomodule are investigated and calculated. The heat load generated by resistive wall wakefields is considered as well. Results are presented for power losses of every element in the 1.3-GHz cryomodule, caused by HOM excitation in the acceleration RF system of the continuouswave linac of SHINE.

关键词： Power loss Higher-order modes (HOMs) Resistive wall wakefields Impedance Superconducting cavities

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MiR-122 in hepatic function and liver diseases

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Protein & Cell 2012年第5期3卷 364-371页

作者： Jun Hu Yaxing Xu Junli hao Saifeng wang Changfei Li Songdong meng CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CAS)Beijing 100101China

As the most abundant liver-specific microRNA,mi-croRNA-122(miR-122)is involved in various physio-logical processes in hepatic function as well as in liver *** is now compelling evidence that miR-122,as a regulator of gene networks and pathways in hepatocytes,plays a central role in diverse aspects of hepatic function and in the progress of liver *** liver-enriched transcription factors-regulated miRNA promotes differentiation of hepatocytes and regulates lipid *** regard to liver diseases,miR-122 was shown to stimulate hepatitis C virus(HCV)replication through a unique and unusual interaction with two binding sites in the 5′-UTR of HCV genome to mediate the stability of the viral RNA,whereas inhibit the expression and replication of hepatitis B virus(HBV)by a miR-122-cylin G1/p53-HBV enhancer regulatory *** addition,miR-122 acts as a suppressor of cell prolif-eration and malignant transformation of hepatocytes with remarkable tumor inhibition ***,a clinical trial targeting miR-122 with the anti-miR-122 oli-gonucleotides miravirsen,the first miRNA targeted drug,has been initiated for treatment of HCV *** further understanding of the comprehensive roles of miR-122 in hepatic functions and the mechanisms in-volved in miR-122 down-regulation in chronic hepatitis or hepatocellular carcinoma,miR-122 appears to be a promising candidate for effective therapeutic ap-proaches against tumor and infectious diseases.

关键词： miR-122 liver development lipid metabo-lism hepatitis C virus(HCV) hepatitis B virus(HBV) hepa-tocellular carcinoma(HCC)

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Anterior bone loss after cervical disc replacement: A systematic review

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World Journal of Clinical Cases 2020年第21期8卷 5284-5295页

作者： Xiao-Fei wang Yang meng hao Liu Ying Hong Bei-Yu wang Department of Orthopaedic Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Anesthesia and Operation Center/West China School of Nursing West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains *** studies have reported the clinical characteristics of ABL and speculated on the pathogenic mechanism based on a certain type of artificial disc,while the overall understanding of ABL is *** To describe the prevalence,impacts,and risk factors of ABL after *** We searched the PubMed,Cochrane Library,and Excerpta Medica databases using the terms“bone loss”or“bone remodeling”or“bone absorption”or“osteolysis”or“implant loosening”or“implant migration”or“hypersensitivity”or“hyperreactivity”,“cervical disc replacement”or“cervical disc arthroplasty”or“total disc replacement”.Eligible manuscripts on the prevalence and impacts of ABL were reviewed by the *** extraction was performed using an established extraction *** results of the included studies were described *** Six studies met the inclusion and exclusion *** was a prospective study and the others were retrospective studies.A total of 440 patients with 536 segments were *** artificial cervical discs included Bryan,Baguera-C,Discocerv,and *** prevalence of ABL ranged from 3.13%to 91.89%,with a combined overall prevalence of 41.84%.ABL occurred within 6 mo and stopped 12 mo after *** cases were noted to have a self-healing *** ABL resulted in segmental kyphosis,implant subsidence,and persistent neck *** may be related to heterotopic *** surgery may be one of the risk factors for *** ABL is a common condition after *** underlying mechanisms of ABL may include stress concentration and injury to nutrient *** should be considered a complication after CDR as it was associated with neck pain,implant subsidence,and heterotopic ossification.

关键词： Bone loss Bone remodeling Stress shielding Risk factor Systematic review

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