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INFLUENCES OF DENSITY AND DIMENSION OF CARBON NANOTUBES ON THEIR FIELD EMISSION

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 302-308页

作者： Y.B.Zhu w.L.w.ng C.G.Hu DepartmentofPhysics JiangsuNormalUniversitySuzhou221009ChinaManuscriptreceived25November2002 DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China

The influences of density and dimension of carbon nanotubes on their electron emission from arrays are studied. The tip electric field of nanotubes, electric field enhancement factor, and optimum nanotube density are expressed by analytic equations. The theoretical analyses show.that the field enhancement factor is sensitive to nanotube density, and can be sharply improved at a specific and optimum density. Some experiments have demonstrated these. Ow.ing to electrostatic screening effect, the length of carbon nanotubes has little effect on their emission. A uniformly-distributed carbon nanotube array model is set up, and applied to analysis of carbon nanotube arrays. The results obtained here are in good agreement w.th the experimental data.

关键词： carbon nanotube array field emission optimum density

Pancreatic cancer: Are 'liquid biopsies' ready for prime-time?

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w.rld Journal of Gastroenterology 2016年第32期22卷 7175-7185页

作者： Alexandra R Lew.s Juan w.Valle Mairead G Mc Namara The Christie NHS Foundation Trust M20 4BX ManchesterUnited Kingdom Institute of Cancer Sciences University of ManchesterM20 4BX ManchesterUnited Kingdom

Pancreatic cancer is a disease that carries a poor prognosis. Accurate tissue diagnosis is required. Tumours contain a high content of stromal tissue and therefore biopsies may be inconclusive. Circulating tumour cells(CTCs) have been investigated as a potential "liquid biopsy" in several malignancies and have proven to be of prognostic value in breast, prostate and colorectal cancers. They have been detected in patients w.th localised and metastatic pancreatic cancer w.th sensitivities ranging from 38%-100% using a variety of platforms. Circulating tumour DNA(ct DNA) has also been detected in pancreas cancer w.th a sensitivity ranging from 26%-100% in studies across different platforms and using different genetic markers. How.ver, there is no clear consensus on w.ich platform is the most effective for detection, nor w.ich genetic markers are the most useful to use. Potential roles of liquid biopsies include diagnosis, screening, guiding therapies and prognosis. The presence of CTCs or ct DNA has been show. to be of prognostic value both at diagnosis and after treatment in patients w.th pancreatic cancer. How.ver, more prospective studies are required before this promising technology is ready for adoption into routine clinical practice.

关键词： Pancreatic Cancer Liquid biopsy Circulating Tumour Cells Circulating Tumour DNA

Liver surgery and transplantation in China: Progress and Challenges

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Frontiers of Medicine 2007年第1期1卷 1-5页

作者： LAU w.Y LAI E C H Department of Surgery The Chinese University of Hong KongPrince of Wales HospitalShatinNew TerritoriesHong Kong SAR.China

From the limited but available information,w. traced the history of developments of liver surgery and transplantation in *** surgery first started in the late 1950s in China,and it soon flourished mainly because of the great demand in liver surgery and the emergence of a number of giants in liver *** recognized and honoured the important contributions of these Chinese pioneers in portal hypertension,recurrent pyogenic cholangitis,hepatocellular carcinoma and liver transplantation.

关键词： liver surgery transplantation

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Acta Mechanica Sinica 2010年第4期26卷 567-572页

作者： D.J.Colquitt A.B.Movchan I.S.Jones w.Daniels Department of Mathematical Sciences University of Liverpool School of Engineering John Moores University Serco Assurance w.lton House 404 The QuadrantBirchwood ParkRisleyWarringtonCheshireWA3 6GAUK

The paper presents a computational model for elastic w.ves in a structured w.ld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of w.ves w.th the micro-structure of the w.ld. Effects of localisation and channeling of w.ves are addressed. A model of a grain structure w.thin the w.ld is also considered.

关键词： Macro-structured w.lds w.ves in stratified media Dispersion Localisation

Nonsingularity of Grain-like cascade FSRs via semi-tensor product

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Science China(Information Sciences) 2018年第1期61卷 58-69页

作者： Jianquan LU Meilin LI Yang LIU Daniel w.C.HO Jrgen KURTHS School of Mathematics Southeast University College of Mathematics Physics and Information Engineering Zhejiang Normal University Department of Mathematics City University of Hong Kong Potsdam Institute for Climate Impact Research

In this paper, Grain-like cascade feedback shift registers(FSRs) are regarded as tw. Boolean netw.rks(BNs), and the semi-tensor product(STP) of the matrices is used to convert the Grain-like cascade FSRs into an equivalent linear equation. Based on the STP, a novel method is proposed herein to investigate the nonsingularity of Grain-like cascade FSRs. First, w. investigate the property of the state transition matrix of Grain-like cascade FSRs. w. then propose their sufficient and necessary nonsingularity condition. Next,w. regard the Grain-like cascade FSRs as Boolean control netw.rks(BCNs) and further provide a sufficient condition of their nonsingularity. Finally, tw. examples are provided to illustrate the results obtained in this paper.

关键词： Grain-like cascade FSRs Boolean control netw.rks Boolean netw.rks semi-tensor product nonsingularity

High-resolution precipitation variations in the Northeast Tibetan Plateau over the last 800 years documented by sediment cores of Qinghai Lake

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Chinese Science Bulletin 2003年第14期48卷 1451-1456页

作者： ZHANGJiaw. JINMing CHENFahu R.w.Battarbee A.CoG.Henderson CenterforAddEnvironmentandPaleoclimateResearch NationalLab.ofWesternChina'sEnvironmentalSystemLanzhouUniversityLanzhou730000China DesertandDesertificationLab. ColdandAridRegionsEnviron-mentalandEngineeringResearchInstituteChineseAcademyofSci-encesLanzhou730000China EnvironmentalChangeResearchCenter DepartmentofGeographyUniversityCollegeLondon26BedfordWayWC1H0APUK

Short cores of about 80-cm retrieved from three main basins of the deepw.ter areas in Qinghai Lake, the largest inland enclosed lake in China, w.re studied. Stable isotopes of authigenic carbonates, grain-size, carbonate and organic matter content at 5-year resolution are used to reconstruct the climatic history over the last 800 years in the Northeastern Tibetan Plateau. Chronology w.s established according to 210Pb dating and 137Cs methods and the core correlation. It is found that cores from different deep basins of the lake can be w.ll correlated. The sedimentary rate is highest in the w.stern basin of the lake and low.st in the east. In the southern basin of the lake w.ere the short core Qing-6 is located, the recent average sedimentation rate is 0.1004 cm/yr. Variations in effective precipitation recorded by the oxygen isotopes and grain size data during the last 800 years are consistent w.th the glacial accumulation record form the Dunde and Guliya ice cores. A dry climate lasted for 300 years from 1200 AD to 1500 AD, follow.d by a w.t period from 1500 to 1560 AD. The tw. dry periods, 1560 to 1650 AD and 1780 to 1850 AD, w.re the results of southw.st monsoon w.akening. The effective precipitation generally increased since 1650 AD due to the strengthening of the Asian Southw.st Monsoon, resulting in a w.t period until the 1950s. Except the early stage, the Little Ice Age on the Plateau is characterized by increased effective moisture. Organic mat- ter content, w.th nearly 200-year cycles, show. similar trend w.th the atmospheric delta carbon-14 before the 1850s, indicating that the bioproductivity responds to solar activity.

关键词：中国西藏东北部青海湖沉积岩心古气候碳酸盐氧同位素有效降水量

A novel reductive ring-opening reaction of isoxazolidine to form functionalized 1,3-aminoalcohol

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Chinese Chemical Letters 2007年第6期18卷 629-632页

作者： w.ng Hong Chan Albert w.M. Lee w.i Yeung w.ng Department of Chemistry Hong Kong Baptist University Kowloog Tong Hong Kong

Reductive cleavage of the NO bond of isoxazolidine ring w.th catalytic hydrogenation over Raney nickel w.s described. Bicyclic isoxazolidines could be effectively converted into the corresponding 1,3-amino-alcohol possessing a sultone or sultam moiety w.th high conversion and yield w.en the hydrogenation w.s catalyzed by freshly prepared Raney nickel under a pressure of 40 psi in the presence of triethylamine.

关键词： Isoxazolidine Hydrogenation Raney nickel 1,3-Amino-alcohol

Perception of artificial conspecifics by bearded dragons(Pogona vitticeps)

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Integrative Zoology 2019年第2期14卷 214-222页

作者： Anna FROHNw.ESER Thomas w.PIKE John C.MURRAY Anna w.LKINSON School of Life Sciences University of LincolnLincolnUK School of Computer Science University of LincolnLincolnUK w.ldlife Research Center Kyoto UniversityKyotoJapan

Artificial animals are increasingly used as conspecific stimuli in animal behavior ***,researchers often have an incomplete understanding of how.the species under study perceives conspecifics,and,hence,w.ich features are needed for a stimulus to be perceived *** investigate the features that bearded dragons(Pogona vitticeps)attend to,w. measured their lateralized eye use w.en assessing a successive range of *** ranged through several stages of realism in artificial conspecifics,to see how.features such as color,the presence of eyes,body shape and motion influence *** found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific,as w.ll as the artificial conspecific’s ***,this approach can inform the design of robotic animals that elicit biologically-meaningful responses in live animals.

关键词： bearded dragons conspecifics lateralized eye use perception

Effect of High-Protein Breakfast Meals on w.thin-Day Appetite and Food Intake in Healthy Men and w.men

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Food and Nutrition Sciences 2015年第3期6卷 386-390页

作者： w.lliam Buosi David M. Bremner Graham w. Horgan Claire L. Fyfe Alexandra M. Johnstone Row.tt Institute of Nutrition and Health University of Aberdeen Aberdeen UK Biomathematics and Statistics Scotland Aberdeen UK

Breakfast is considered an important meal for daily appetite control. w. examined the effect of high-protein breakfasts on w.thin-day appetite sensations and subsequent ad libitum intake, in men and w.men. Tw.nty subjects attended on 4 occasions, to consume in a randomised order high-protein (30% energy) breakfast meals, as, 1) maintenance (MTD) fed to energy requirements (2.67 MJ), 2) a w.ight-loss (w.) bacon-based meal breakfast (w.-B, 2.13 MJ), 3) a w.-chicken salad (w.-CS, 2.13 MJ) and 4) a w.-smoothie (w.-S, 2.08 MJ). The 3 HP-w. breakfasts elicited differences in hunger (p = 0.007), fullness (p = 0.029), desire to eat (p = 0.006) and prospective consumption (p = 0.020). The w.-B meal reduced hunger (p = 0.002) and enhanced fullness (p = 0.02), compared w.th the tw. other w. breakfasts. Although these differences w.re not reflected in ad libitum energy intake later in the day, a HP breakfast can modify morning satiety, w.ich is important during dieting.

关键词： Protein Appetite w.ight Loss Breakfast Meals Lunch Intake