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地质学报 1930年第2期 102-105页

作者： f. E. LICENT Musee Hoangho Paiho

Nan Ye Li is a little village, lying about 80 kilometers West from Cheng Ting fu, along the mountains, at some 370 meters above the level of the great Hopei plain.

关键词： THE NAN YE LI SANMENIAN fOSSILIfEROUS DEPOSIT Li

Dielectric Properties of fe73.5-Cu1-Ta3-Si13.5-B9 Magnetic Alloy

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Journal of Physical Science and Application 2016年第3期6卷 25-29页

作者： M Z Ahsan f A Khan Military Institute of Science and Technology Mirpur-12 Dhaka-1216 Bangladesh Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh

The studied sample is a metallic glass in fe-Si-B system. It is developed with the nominal composition of fe735-Cu1-Ta3-Si13.5-B9 by single-roller melt spinning technique in air. The dielectric constant and loss factor have been measured both for as cast and annealed samples using Agilent Impedance analyzer. They are found to decrease with frequency up to 10 MHz and remain constant afterwards. The decrease of dielectric constant and loss factor with frequency is due to ceasing of orientational polarizability. Their constancy is owing to presence of only electronic contribution to its polarizability above 10 MHz. Three distinct regions （1-4 MHz, 4-10 MHz and 10 MHz-1 GHz） also noticed from its frequency dependence, which might make it useful in switching and sensor devices. The temperature dependence of dielectric constant and loss factor maintain inverse relationship：（1） dielectric constant increases, and （2） loss factor decreases with annealing temperature for structural relaxation due to thermal agitation.

关键词： Magnetic alloy dielectric constant loss factor dielectric loss tanS annealing temperature.

The messier objects as a tool in teaching astronomy

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Natural Science 2013年第3期5卷 321-325页

作者： Jesus Rodrigo f. Torres Rizal Technological University Mandaluyong The Philippines

The french astronomer Charles Messier (1730- 1817) compiled a catalogue [1] of astronomical objects which reached109 innumber after additions by later astronomers were added. The catalogue contains galaxies, emission nebulae, a supernova remnant, a double star, globular clusters, open clusters, an asterism, a star cloud, and planetary nebulae. While the objective of Messier in compiling the catalogue was to guide comet hunters not to be confused by his objects which he thought looked like comets [2], the Messier Catalogue as it later became known became a standard guide to astronomers for a study of the sky’s “greatest hits” or the best samples of objects which can be observed and studied. This paper explores the value of the Messier Catalogue in the teaching of Astronomy and Earth Science. The range of objects is wide and contains some of the best examples of their type. The teaching method I propose is the actual observations of the objects through a telescope, with the corresponding explanation. Some principles which will be covered through this process are stellar evolution from the birth and death of stars, galaxy types, formation of galaxies, galactic interactions, life in the Universe, cosmology, and our place in the Universe.

关键词： Astronomy Earth Science Education Astronomical Observing Messier Objects

Studies into the association between LDL-C lowering and cognitive function:time to forget about it?

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Science Bulletin 2021年第16期66卷 1614-1615页

作者： Shirin Ibrahim Laurens f.Reeskamp G.Kees Hovingh Department of Vascular Medicine Amsterdam UMCUniversity of Amsterdam1105 AZ Amsterdamthe Netherlands

Lipid lowering is the cornerstone in the prevention of cardiovascular disease(CVD),which is based on a plethora of data bolstering the causal role of low-density lipoprotein cholesterol(LDL-C)in the process of ***,a concern that has been raised in this regard is whether LDL-C lowering agents,or the subsequent low LDL-C levels,result in cognitive impairment,offsetting the beneficial effect of LDL-C lowering on CVD outcomes.

关键词：认知损害 prevention Lipid

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Gauge boson mass generation–without Higgs–in the scalar strong interaction hadron theory

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Natural Science 2010年第4期2卷 398-401页

作者： f. C. Hoh 不详

It is shown that the gauge boson mass is natu-rally generated–without Higgs–in the pion beta decay using the scalar strong interaction had-ron theory. This mass generation is made pos-sible by the presence of relati... 详细信息

关键词： No Higgs Gauge Boson Mass Scalar Strong Interaction

Lessons from rare tumors: Hepatic lymphoepithelioma-like carcinomas

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World Journal of Gastroenterology 2015年第12期21卷 3472-3479页

作者： Antonio Solinas Diego f Calvisi Department of Biomedical Sciences University of Sassari Department of Clinical and Experimental Medicine University of Sassari Institute of Pathology University of Greifswald

In this review we focus on lymphoepitheliomalike hepatocellular carcinomas(LEL-HCC) and lymphoepithelioma-like cholangiocarcinomas(LEL-ICC). Despite their rarity, these tumors are of general interest because of their epidemiological and clinical features, and because they represent a distinct model of interaction between the immune systemand neoplastic cells. Approximately half of LELHCC arise in the context of chronic hepatitis C virus(HCV) infection and have been described both in Eastern and Western patients. By contrast, LEL-ICC is associated in almost all cases with Epstein-Barr virus(EBV) infection and exhibits the same epidemiological features of EBV related malignancies. Compared with classical hepatocellular carcinoma and intrahepatic cholangiocarcinoma of corresponding stage, both LEL-HCC and LEL-ICC are characterized by lower rates of recurrence after surgery and better overall survival. How this behavior is related to distinct genetic alterations and tumor microenvironment is unclear. The pathophysiological mechanisms of lymphoid infiltrations seem to be different among the two groups of tumors. In fact, LEL-HCC frequently arises in the context of inflammatory changes driven by HCV infection, and has been recognized as a variant of classical hepatocellular carcinoma. At variance, lymphocyte recruitment of LEL-ICC is similar to that described in nasopharyngeal carcinoma and gastric LEL, and possibly depends on the expression pattern of latent EBV infection.

关键词： Lymphoepithelioma Lymphoepithelioma-like carcinoma

Converting lateral scanning into axial focusing to speed up three-dimensional microscopy

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Light(Science & Applications) 2020年第1期9卷 429-440页

作者： Tonmoy Chakraborty Bingying Chen Stephan Daetwyler Bo-Jui Chang Oliver Vanderpoorten Etai Sapoznik Clemens f.Kaminski Tuomas P.J.Knowles Kevin M.Dean Reto fiolka Department of Cell Biology UT Southwestern Medical CenterDallasTXUSA Department of Physics and Astronomy University of New MexicoAlbuquerqueNMUSA Department of Chemical Engineering and Biotechnology University of CambridgeCambridge CB30ASUK Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK Lyda Hill Department of Bioinformatics UT Southwestern Medical CenterDallasTXUSA

In optical microscopy,the slow axial scanning rate of the objective or the sample has traditionally limited the speed of volumetric ***,by conjugating either a movable mirror to the image plane in a remote-focusing geometry or an electrically tuneable lens(ETL)to the back focal plane,rapid axial scanning has been ***,mechanical actuation of a mirror limits the axial scanning rate(usually only 10–100 Hz for piezoelectric or voice coil-based actuators),while ETLs introduce spherical and higher-order aberrations that prevent high-resolution *** an effort to overcome these limitations,we introduce a novel optical design that transforms a lateral-scan motion into a spherical aberration-free axial scan that can be used for high-resolution *** a galvanometric mirror,we scan a laser beam laterally in a remote-focusing arm,which is then back-reflected from different heights of a mirror in the image *** characterize the optical performance of this remote-focusing technique and use it to accelerate axially swept light-sheet microscopy by an order of magnitude,allowing the quantification of rapid vesicular dynamics in three *** also demonstrate resonant remote focusing at 12 kHz with a two-photon raster-scanning microscope,which allows rapid imaging of brain tissues and zebrafish cardiac dynamics with diffraction-limited resolution.

关键词： mirror axial image

In silico characterization of the functional and structural modules of the hemagglutinin protein from the swine-origin influenza virus A (H1N1)-2009

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Science China(Life Sciences) 2010年第6期53卷 633-642页

作者： Christopher VAVRICKA GAO George f CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences Graduate University of Chinese Academy of Sciences China-Japan Joint Laboratory of Molecular Immunology and Molecular Microbiology Institute of MicrobiologyChinese Academy of Sciences Beijing Institutes of Life Science Chinese Academy of Sciences

The 2009 swine-origin influenza virus (S-OIV,H1N1 subtype) has developed into a new pandemic influenza as announced by the World Health *** order to uncover clues about the determinants for virulence and pathogenicity of the virus,we characterized the functional modules of the surface glycoprotein hemagglutinin (HA),the most important protein in molecular epidemiology and pathogenesis of influenza *** analyzed receptor binding sites,basic patch,neutralization antibody epitopes and T cell epitopes in the HA protein of the current S-OIV according to the corresponding functional and structural modules previously characterized in other H1 HA molecules or HA molecules of other *** compared their differences and similarities *** on the amino acids defined as the functional and structural modules,the HA protein of 2009 S-OIV should specifically bind to the human 2,*** D225G/E mutation in HA,which is found in some isolates,may confer dual binding specificity to the 2,3and 2,6-receptor based on previously reported *** HA variant contains two basic patches,one of which results in increased basicity,suggesting enhanced membrane fusion *** 2009 S-OIV HA also has an extra glycosylation site at position *** of the five antibody neutralization epitopes identified in A/RP/8/34(H1N1) were exposed,but the other was hidden by a glycosylation *** previously identified cytotoxic T cell epitopes in various HA molecules were summarized and their corresponding sequences in 2009 S-OIV HA were *** results are critical for understanding the pathogenicity of the virus and host immune response against the virus.

关键词： 2009 S-OIV hemagglutinin in silico structural and functional modules

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Energy Aware Spectrum Access in Cognitive Radio Networks with Imperfect Channel Sensing

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China Communications 2012年第9期9卷 127-130页

作者： Wei Yifei Du Chenhui feng Ruijun f. Richard Yu Beijing University of Posts and Telecommunications Beijing 100876 P. R. China China Mobile Communications Corporation Beijing 100032 P.R. China Department of Systems and Computer Engineering Carleton University Ottawa ON Canada

Due to the problem of spectrum underuti-lization and energy inefficiency in wireless commu-nications, the research on energy efficient Cogni-tive Radio Networks （CRNs） has received signifi-cant attention in both industry and academia. In this paper, we consider the problem of optimal spectrum selection and transmission parameters de-sign with the objective of minimizing energy con-sumption in CRNs. Since the system state cannot be directly observed due to miss detections and estimation errors, we formulate the optimal spec-trum access problem as a Partially Observable Markov Decision Process （POMDP）. In particular, the proposed scheme selects the optimal spectrum, modulation and coding scheme, transmission pow-er, and link layer frame size in each time slot ac-cording to the belief state, which captures all the history information of past actions and observa- tions. The optimal policy can be acquired by sol-ving POMDP problem with linear programming based algorithm Sinmlation results show that sig-nificant energy savings can be achieved by the proposed scheme.

关键词： spectrum access cognitive radio POMDP

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