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RNA Structural Homology Search with a Succinct Stochastic Grammar Model

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Journal of Computer Science & Technology 2005年第4期20卷 454-464页

作者：宋英磊赵继贞刘春梅刘戡 RussellMalmberg 蔡黎明 DepartmentofComputerScience UniversityofGeorgiaAthensGA30602U.S.A. DepartmentofPlantBiology UniversityofGeorgiaAthensGA30602U.S.A.

An increasing number of structural homology search tools, mostly based on profile stochastic context-free grammars (SCFGs) have been recently developed for the non-coding RNA gene identification. SCFGs can include statistical biases that often occur in RNA sequences, necessary to profile specific RNA structures for structural homology search. In this paper, a succinct stochastic grammar model is introduced for RNA that has competitive search effectiveness. More importantly, the profiling model can be easily extended to include pseudoknots, structures that are beyond the capability of profile SCFGs. In addition, the model allows heuristics to be exploited, resulting in a significant speed-up for the CYK algorithm-based search.

关键词： RNA 核糖核酸 SCFGs 结构

Changshanian Maximum Flooding Event in China and Its Global Correlation

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 341-355,451页

作者： M.E.Tucker u niverSity of Durhnm.u.K.

Various orders of condensed sections are recognized in the Cambrian of North China Carbonate Platform. Study of comparative sedimentology proves that CS4-CS5 in the Changshanian age is the maximum sea flooding sediments in the Cambrian, regardless of the distribution, thickness, internal structure of the condensed section series and K2O abundance. It is a two-layered composite condensed section series, characterized by the enrichment of such elements as K, P, Mn, Ti, Co, V, Cr, Cu, Zr, Ni, Li, Th, La, Ce, Nd, Dy, Y, Sc and Be. The Changshanian maximum flooding event can be correlated on a global scale, and the corresponding sedimentary records are discovered in 26 intercontinental sections in N. Europe, N. America, and Tarim and the Yangtze Platform of China. Through detailed sedimentological research, meter-scale cycle analysis and Fischer plots, it is concluded that the Changshanian maximum flooding was a composite effect of the second-order eustacy superimposed by the third-and fourth-order eustacy, which lasted for 1.2-3 Ma. An intercontinental model of the Changshanian maximum flooding is proposed at the end of this paper.

关键词： Changshanian age maximum flooding event condensed section global correlation Cambrian

ELECTROWEAK MODEL AND CONSTRAINTS ON NEW PHYSICS

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Chinese Physics C 2016年第10期40卷 151-171页

作者： J. Erler A. Freitas u. Mexico Pittsburgh u.

10.1 Introduction 10.2 Renormalization and radiative corrections 10.3 Low energy electroweak observables 10.4 W and Z boson physics 10.5 Precision flavor physics 10.6 Experimental results 10.7 Constraints on new physics

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Evaluation of natamycin in commercial dairy products by a green capillary zone electrophoresis method and confirmation with a Liquid Chromatography-Mass Spectrometry

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Food Bioscience 2022年第6期50卷 1047-1056页

作者： Senem Şanlı Sinem Kılıçarslan NurullahŞanlı Department of Chemistry Faculty of Science and ArtsUşak UniversityUŞAKTurkey Department of Food Engineering ChemistryFaculty of EngineeringUşak UniversityUŞAKTurkey Department of Chemistry and Physics Roger Williams UniversityOne Old Ferry RoadBristolRI02809USA

In the present study,a simple,rapid,sensitive,robust,convenient,economical and environmentally friendly Capillary Zone Electrophoresis(CZE)method based on the use of non-toxic chemicals was developed to monitor the concentrations of natamycin,which is used to prevent mold and yeast that may occur in cheese crust,cheese crumb,yogurt and ***,a LC-ESI-MS method was developed and used for confirmation as *** validated methods produced excellent results in terms of linearity(R2>0.999)and recovery values(ranging from 99.06%to 100.54%)and successfully applied for the analysis of natamycin,according to European regulations and Turkish Food Codex in 14 different brands of ayran,17 different brands of yogurt and 12 different brands of Kashar cheese collected from local *** demonstrated flexibility,sensitivity and selectivity,accuracy,robustness,and low *** developed CZE method is very advantageous because it is environmentally friendly and economical due to the analysis time and the absence of organic *** addition,the reliability of the study was increased by using the internal standard and possible errors were *** CZE and LC-MS methods provided good results for natamycin analysis and these methods can be used for natamycin analysis in dairy products and possible ***,embracing the primary concepts of green chemistry,the proposed technique can be taken into consideration friendly to the nature,sustainable and“reagent-free”.These assays are easily applicable as quality control methods for natural products and pharmaceuticals containing natamycin.

关键词： Natamycin Capillary zone electrophoresis Green chemistry LC-ESI-MS Dairy Cheese Yogurt Pharmaceuticals

LIGHT PORTABLE ELECTROPNEuMATIC LOuDSPEAKER

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Chinese Journal of Acoustics 1989年第4期8卷 359-365页

作者： MACDONALD D.L. Racal Acoustics Ltd.u.K

This paper analyses the influence of certain parameters and factors on the characteristics of the electropneumatic loudspeaker and describes the experimental work carried out. The developed portable electropneumatic loudspeaker possesses good properties with a flat frequency response from 400 Hz to 2 kHz and a maximum sound pressrue output of 120dB at a distance 2 metre on axis from the horn mouth .The magnetic flux density at the magnetic gap is 19 ,000 gauss .The electropneumatic loudspeaker is small in size and lightweight.

关键词： LIGHT PORTABLE ELECTROPNEuMATIC LOuDSPEAKER

GRAND uNIFIED THEORIES

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Chinese Physics C 2016年第10期40卷 290-302页

作者： A. Hebecker J. Hisano u. Heidelberg Nagoya u.

16.1. The Standard Model The Standard Model （SM） may be defined as the renormalizable field theory with gauge group GSM = Su（3）C × Su（2）L × u（1）y, with 3 generations of fermions in the representation

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Kinetic Studies of Electrochemical Oxidation of 1,3-Benzenedithiol

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Chemical Research in Chinese universities 1993年第3期9卷 231-239页

作者： H.S.Lee X.Q.Yang J.McBreen T.A.Skotheim Brookhaven National Laboratory Upton NY 11973 U.S.A. Brookhaven National Laboratory Upton NY 11973 U.S.A. Brookhaven National Laboratory Upton NY 11973 U.S.A. Moltech Corporation Stony Brook NY 11790-3350 U.S.A.

The electrochemical oxidation of 1, 3-benzenedithiol was investigated in a 0. 100 mol/L tetrabutylammonium perchlorate/acetonitrile electrolyte. The electrochemical techniques used were potential sweep, bulk electrolysis, rotating disc and the potential step method. The combination of the techniques yielded the number of electrons transferred per molecule, the reaction order, the transfer coefficient, the diffusion coefficient and concentration of dithiol anions, the standard heterogeneous rate constant as well as the formal potential and equilibrium constant of the preceeding dissociation reaction. This paper also illustrates the methods for studying the electrode kinetics of reactions which (a) involve a chemical reaction preceeding the electron-transfer process, (b) have insoluble polymer products, and (c) are totally irreversible.

关键词： Electrochemical oxidation 1,3-Benzenedithiol Electrode kinetics Organ-ic disulfide

Effective data sampling strategies and boundary condition constraints of physics-informed neural networks for identifying material properties in solid mechanics

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1039-1068页

作者： W.Wu M.DANEKER M.A.JOLLEY K.T.TuRNER L.Lu Department of Anesthesiology and Critical Care Medicine Children's Hospital of PhiladelphiaPhiladelphiaPA 19104U.S.A. Division of Pediatric Cardiology Children's Hospital of PhiladelphiaPhiladelphiaPA 19104U.S.A. Department of Chemical and Biomolecular Engineering University of PennsylvaniaPhiladelphiaPA 19104U.S.A. Department of Mechanical Engineering and Applied Mechanics University of PennsylvaniaPhiladelphiaPA 19104U.S.A.

Material identification is critical for understanding the relationship between mechanical properties and the associated mechanical ***,material identification is a challenging task,especially when the characteristic of the material is highly nonlinear in nature,as is common in biological *** this work,we identify unknown material properties in continuum solid mechanics via physics-informed neural networks(PINNs).To improve the accuracy and efficiency of PINNs,we develop efficient strategies to nonuniformly sample observational *** also investigate different approaches to enforce Dirichlet-type boundary conditions(BCs)as soft or hard ***,we apply the proposed methods to a diverse set of time-dependent and time-independent solid mechanic examples that span linear elastic and hyperelastic material *** estimated material parameters achieve relative errors of less than 1%.As such,this work is relevant to diverse applications,including optimizing structural integrity and developing novel materials.

关键词： solid mechanics material identification physics-informed neural network(PINN) data sampling boundary condition(BC)constraint

Gonad traits and age structure of the sea urchin Heliocidaris crassispina in central range:a comparison with rangeextenders

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Journal of Oceanology and Limnology 2023年第5期41卷 1954-1964页

作者： Wenping FENG Daichi NAKANO Nobuyasu NAKABAYASHI Masakazu NAOKI Xiaofei TIAN Yukio AGATSuMA Fisheries College Zhejiang Ocean UniversityZhoushan 316022China Graduate School of Agricultural Science Tohoku UniversitySendai 980-8572Japan Fukui Prefectural university Fukui 910-1195Japan Akita Prefectural Institute of Fisheries Oga 010-8570Japan

The sea urchin Heliocidaris crassispina has northern expanded in geographic range to Toga Bay,Oga Peninsula in the Sea of Japan due to the global *** demonstrate the gonad traits and age structure of *** in the central range and compare the difference with those in northern extended range,we collected 100 *** individuals from a barren off Shitsumi,Fukui(central range),in August *** growth,gonad traits(size,development and color),and sex ratio were investigated and compared with those in Toga Bay,in August 2014(extended range).The successive 2012–2016 year classes of *** indicated successive juvenile recruitment in the central range,as found in the extended *** individuals at three years old in central range were obviously larger than those in the extended range,showing large test diameter and body weight,possibly due to the higher temperature in central range than that in northern extended *** addition,a balanced sex ratio in the central range was found,in contrast to the female-skewed sex ratio found in the extended *** development was sex-and *** testicular development in the central range was not only delayed in comparison to ovarian development,but also less delayed than those in the extended range,which possibly attribute to the higher water temperature in the central range.A significantly lower male gonad index and L*(lightness)value was recorded in central ranges compared to that in extended range,possibly due to the releasement of sperm of *** in central ranges.

关键词： Heliocidaris crassispina age gonad development gonad color range extension