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Frontiers of History in China 2013年第2期8卷 153-175页

作者： steven b. Miles Department of History Washington University in St. Louis St. Louis MO 63130-4899 USA

This article situates the Pearl River delta market town of Jiujiang within a system of market towns and cities along the West River and its tributaries in southern China. Exploring the history of this town as an emigrant community, this article follows the upstream movement of officials, civil service examinees, merchants, and permanent settlers along the West River basin between the sixteenth century and the nineteenth century. The trajectory of migration from this market town was shaped by the geographical factors of the West River system. At the same time, migration, which was related both to strategies that Jiujiang families embraced for socioeconomic advancement and to policies that the Ming and Qing states adopted for controlling the southwestern frontier, played an important role in the historical construction of a unified region linked by economic ties and personal networks.

关键词： market town migration region Ming Qing West River Pearl Riverdelta

The Nature and Impact of Late Imperial Chinese Academies:A Review of Some Recent Publications in China

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Frontiers of Education in China 2015年第4期10卷 634-656页

作者： steven b.MILES Department of History Washington University in St.LouisSt.LouisMO 63130-4899USA

This review essay analyzes the historiography of Confucian academies(shuyuan)in imperial China,focusing on five representative books published in China between 2008 and 2014,including two new editions of books originally published in 1995 and *** five authors share a deep concern about the nature of academies,particularly their relationship with the state.A secondary theme that these books address is the impact that academies had on late imperial Chinese culture and *** together,these five works show how research on academies in imperial China has evolved over the past two decades.

关键词： academies shuyuan historiography imperial China

The Discrete Orthogonal Polynomial Least Squares Method for Approximation and Solving Partial Differential Equations

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Communications in Computational Physics 2008年第3期3卷 734-758页

作者： Anne Gelb Rodrigo b.Platte W.steven Rosenthal Department of Mathematics and Statistics Arizona State UniversityTempeArizona 85287USA

We investigate numerical approximations based on polynomials that are orthogonal with respect to a weighted discrete inner product and develop an algorithm for solving time dependent differential *** focus on the family of super Gaussian weight functions and derive a criterion for the choice of parameters that provides good accuracy and stability for the time evolution of partial differential *** results show that this approach circumvents the problems related to the Runge phenomenon on equally spaced nodes and provides high accuracy in *** time stability,small corrections near the ends of the interval are computed using local polynomial *** numerical experiments illustrate the performance of the method.

关键词： Discrete least-squares orthogonal polynomials spectralmethods high order numerical methods uniform grid.

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.Smith steven M.Smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

VARIAbLE STEP-SIZE IMPLICIT-EXPLICIT LINEAR MULTISTEP METHODS FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven J. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have been developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementable variable step-size implicit-explicit （VSIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VSIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the burgers＇ equation. These results demonstrate that by varying the time step-size, VSIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical behavior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variable step-size Zero-stability burgers' equation.

SPECTRAL IMAGING AND ANALYSIS TO YIELD TISSUE OPTICAL PROPERTIES

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Journal of Innovative Optical Health Sciences 2009年第2期2卷 123-129页

作者： steven L.JACQUES Departments of Dermatology and biomedical Engineering Oregon Health&Science University PortlandOregonUSA

An introduction to the basics of spectral imaging as applied to biological tissues is *** example of a spectral image of a face is used to demonstrate the data and spectral analysis that specify the melanin content(M),blood content(b),tissue oxygen saturation(S),water content(W),fraction of scattering due to Rayleigh scattering(f)and due to Mie scattering(1−f),and the reduced scattering coefficient at 500-nm wavelength(µs 500 nm).The sensitivity of reflectance spectra to variation in the various parameters is illustrated.

关键词： Spectroscopy spectral imaging tissue optical properties optical diagnostics.

Mitogen-activated protein kinases mediate the oxidative burst and saponin synthesis induced by chitosan in cell cultures of Panax ginseng

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Science China(Life Sciences) 2004年第4期47卷 303-312页

作者： steven J. NEILL Centre for Research in Plant Science University of the West of England Bristol Coldharbour Lane Bristol BS16 1QY United Kingdom

Chitosan (CHN) specially induced the activities of 39 kD and 42 kD protein kinases in ginseng cells, which could be suppressed by an inhibitor of mitogen-activated protein kinase (MAPK) pathway, PD98059. The immunoprecipitation (IP) using MAPK antibody or kinase assay in vitro also showed that CHN-induced 42 kD and 39 kD protein kinases belonged to the MAPK family. PD98059 suppressed CHN-induced transcriptions of ginseng squalene synthase and ginseng squalene epoxidase genes (gss and gse), CHN-induced accumulation of β-Amyrin synthase (β-AS) and synthesis of saponin. These results showed that CHN-induced activities of MAPKs were necessary for the CHN-induced saponin synthesis. EGTA and LaCl3 suppressed CHN-induced 39 kD and 42 kD MAPK activities. Ruthenium red (RR) could suppress CHN-induced 39 kD activity. All of them suppressed CHN-induced saponin synthesis. These results indicated that CHN-induced increment of cytosolic calcium was necessary for CHN-induced saponin synthesis. PD98059 also suppressed CHN-induced oxidative burst (including the increment of activity of plasma membrane NADPH oxidase and production of H2O2), but diphenylene iodonium (DPI), dimethylthiourea (DMTU) and 2,5-dihydroxycinnamic acid methyl ester (DHC) could not suppress CHN-induced MAPK activities, which indicated that MAPK was possibly function upstream of CHN-induced oxidative burst. Keywords mitogen-activated protein kinase - chitosan - saponin

关键词： mitogen-activated protein kinase,chitosan,saponin.

DNA sequence representation by trianders and determinative degree of nucleotides

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Journal of Zhejiang University-Science b(biomedicine & biotechnology) 2005年第8期6卷 743-755页

作者： DUPLIJ Diana DUPLIJ steven Institute of Molecular biology and Genetics Kiev 03143 UkraineTheory Group Nuclear Physics LaboratoryKharkov National UniversityKharkov 61077 Ukraine

A new version of DNA walks, where nucleotides are regarded unequal in their contribution to a walk is introduced, which allows us to study thoroughly the “fine structure” of nucleotide sequences. The approach is based on the assumption that nucleotides have an inner abstract characteristic, the determinative degree, which reflects genetic code phenomenological prop-erties and is adjusted to nucleotides physical properties. We consider each codon position independently, which gives three separate walks characterized by different angles and lengths, and that such an object is called triander which reflects the “strength” of branch. A general method for identifying DNA sequence “by triander” which can be treated as a unique “genogram” (or “gene passport”) is proposed. The two- and three-dimensional trianders are considered. The difference of sequences fine structure in genes and the intergenic space is shown. A clear triplet signal in coding sequences was found which is absent in the intergenic space and is independent from the sequence length. This paper presents the topological classification of trianders which can allow us to provide a detailed working out signatures of functionally different genomic regions.

关键词： DNA walk Triander Determinative degree Analysis DNA sequences Dystrophin Nucleotide

On-the-fly active learning of interpretable bayesian force fields for atomistic rare events

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npj Computational Materials 2020年第1期6卷 1502-1512页

作者： Jonathan Vandermause steven b.Torrisi Simon batzner Yu Xie Lixin Sun Alexie M.Kolpak boris Kozinsky Department of Physics Harvard UniversityCambridgeMA 02138USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA Center for Computational Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA bosch Research CambridgeMA 02139USA

Machine learned force fields typically require manual construction of training sets consisting of thousands of first principles calculations,which can result in low training efficiency and unpredictable errors when applied to structures not represented in the training set of the *** severely limits the practical application of these models in systems with dynamics governed by important rare events,such as chemical reactions and *** present an adaptive bayesian inference method for automating the training of interpretable,low-dimensional,and multi-element interatomic force fields using structures drawn on the fly from molecular dynamics *** an active learning framework,the internal uncertainty of a Gaussian process regression model is used to decide whether to accept the model prediction or to perform a first principles calculation to augment the training set of the *** method is applied to a range of single-and multi-element systems and shown to achieve a favorable balance of accuracy and computational efficiency,while requiring a minimal amount of ab initio training *** provide a fully opensource implementation of our method,as well as a procedure to map trained models to computationally efficient tabulated force fields.

关键词： fields element typically