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流产后再次妊娠间隔时间对妊娠结局的影响：苏格兰医院回顾性资料分析（摘要）

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英国医学杂志中文版 2010年第6期13卷 368-368页

作者： Eleanor R Love Siladitya Bhattacharya norman c smith Sohinee Bhattacharya 沈洁(译) 杨孜(校) University of Aberdeen Aberdeen Department of Obstetrics and Gynaecology Aberdeen Maternity Hospital Aberdeen Dug aid Baird Centre for Research on Women ' s Health Aberdeen Maternity Hospital Aberdeen AB25 2ZD 北京大学第三医院妇产科

目的探讨初次有记录的妊娠流产后再次妊娠的最佳时间间隔。设计基于人群的回顾性队列研究。地点苏格兰医院，1981年至2000年研究对象 30937名首次妊娠记录为流产的再次妊娠妇女。

关键词：再次妊娠妊娠结局流产后苏格兰间隔时间医院摘要时间间隔

A note on a boundary condition for spouted beds

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Particuology 2010年第6期8卷 536-538页

作者： norman Epstein Department of chemical&Biological Engineering The University of British Columbia2216 Main MallVancouverB.C.Canada V6T 1Z3

The boundary condition, zero solids pressure at the top of a particle bed of maximum spoutable height, Hm, is shown to eliminate any resort to empiricism in the derivation of the fluid velocity in the annulus of a spouted bed for which both viscous and inertial effects are taken into account. The same boundary condition fails when applied to a spouted bed for which the bed height H 〈 Hm, especially when H 〈 0.8Hm.

关键词： Spouted beds Annulus flow Boundary condition Particle-fluid hydrodynamics

Incidence of brain metastasis in patients with esophageal carcinoma

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World Journal of Gastroenterology 2011年第19期17卷 2407-2410页

作者： Ron S smith Robert c Miller Department of Radiation Oncology Andreas Cancer Center-Mayo Health SystemMankatoMN 56002United States Department of Radiation Oncology Mayo ClinicRochesterMN 56002United States

AIM:To determine the incidence of brain metastasis in a contemporary group of patients with carcinoma of the ***:Retrospective analysis of 53 patients with esophageal carcinoma who received radiotherapy as a component of treatment between 1998 and 2007,including patient and tumor characteristics,and subsequent diagnosis of brain *** association between the histological type of esophageal cancer and the incidence of brain metastasis was assessed using Fisher's exact ***:Forty-four of the fifty-three patients in this study had adenocarcinoma and nine had squamous cell carcinoma,ranging from stage ⅡA-Ⅳ*** treatment was surgery with neoadjuvant chemoradiotherapy (trimodality therapy) in 19% of patients;chemoradiotherapy in 42%;and surgery and adjuvant radiotherapy in 7%.Twenty-five percent of patients inthis study received palliative *** overall incidence of brain metastasis in this cohort was 13%.Adenocarcinoma was the primary tumor histology in all of the patients who developed brain metastasis,representing an incidence of 16% in this *** patients with squamous cell carcinoma received trimodality *** association between histology and brain metastasis was not statistically ***:The incidence of brain metastasis in this contemporary cohort of patients with esophageal carcinoma is higher than previously reported and was confined to those with adenocarcinoma.

关键词： Brain metastasis Esophageal carcinoma

Transmission capacity Analysis for Linear VANET under Physical Model

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china communications 2017年第3期14卷 97-107页

作者： Xinxin He Hang Zhang Weisen Shi Tao Luo norman c.Beaulieu Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China

In this study, the transmission capacity of VANETs in a highway scenario is analysed on the basis of a 1D line model and the carrier sense multiple access with collision avoidance(cSMA/cA) protocol. We describe the cSMA/cA protocol used in IEEE802.11 p from the perspective of the geometric relationship amongst simultaneous transmitters. The desired channel and interfering channels are assumed to experience the same amount of path-loss and Rayleigh fading. On the basis of the proposed model, we analyse the attempted transmission probability of each road segment and the maximum intensity of active transmitters, including their theoretical values. Then, we employ the physical model to obtain the outage probability and derive the upper bound of the transmission capacity of a VANET, which is defined as the average spatial density of successful transmissions in the network. Simulation results indicate that the theoretical value offers a good bound on network capacity.

关键词： VANET transmission capacity line model cSMA/cA

Operational Wave Now- and Forecast in the German Bight as a Basis for the Assessment of Wave-Induced Hydrodynamic Loads on coastal Dikes

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Journal of Ocean University of china 2017年第6期16卷 991-997页

作者： DREIER norman FROHLE Peter Institute of River and coastal Engineering Hamburg University of Technology Hamburg Germany

The knowledge of the wave-induced hydrodynamic loads on coastal dikes including their temporal and spatial resolution on the dike in combination with actual water levels is of crucial importance of any risk-based early warning system. As a basis for the assessment of the wave-induced hydrodynamic loads, an operational wave now-and forecast system is set up that consists of i) available field measurements from the federal and local authorities and ii) data from numerical simulation of waves in the German Bight using the SWAN wave model. In this study, results of the hindcast of deep water wave conditions during the winter storm on 5–6 December, 2013(German name ‘Xaver') are shown and compared with available measurements. Moreover field measurements of wave run-up from the local authorities at a sea dike on the German North Sea Island of Pellworm are presented and compared against calculated wave run-up using the Eur Otop(2016) approach.

关键词： German Bight North Sea wave forecast cosmo-Model SWAN hydrodynamic loads wave run-up EurOtop

Organic Gases in Fluid Inclusions of Ore Minerals and Their constraints on Ore Genesis:A case Study of the changkeng Au-Ag Deposit,Guangdong,china

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 86-94页

作者： DavidI.norman Department of Earth & Environmental Sciences New Mexico Institute of Mining and Technology (NMT) Socorro NM87801 USA

The newly discovered changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from thechangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes c_(1-4) and unsaturatedalkenes c_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg c, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic *** on the compositions of organic gases in fluid inclusions, the authors infer that the changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belon

关键词： ore mineral fluid inclusion organic gas changkeng Au-Ag deposit

convolutional neural network to learn building-shape representations for early-stage energy design

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Energy and AI 2023年第4期14卷 463-478页

作者： Manav Mahan Singh Ian F.c.smith Georg Nemetschek Institute Artificial Intelligence for the Built World Technical University of MunichWalther-von-Dyck-Straße 10Garching bei München 85748Federal Republic of Germany

Machine learning(ML)supports energy-efficient design by quickly predicting the building performance at early ***,existing ML approaches cannot easily learn geometrical representations and their interactions with technical specifications for predicting *** approaches of artificial neural networks(ANN)use either numerical parameters to represent building geometry or component-based ML(cBML)to train trans-ferrable ML ***,both approaches have high generalisation errors for complex *** used a convolutional neural network(cNN)to learn geometrical representations of buildings and an autoencoder to optimise the training *** test existing approaches of ANN and cBML with a proposed approach of cNN for different sizes of training *** the biggest training dataset,ANN,cBML,and cNN have generalisation errors(root-mean-squared errors)of 1.35,1.60,and 0.77 kWh/a.m 2,*** cBML has lower prediction errors on small datasets,cNN is more suitable for large ***,cNN most often has better prediction accuracy than ANN and trains faster on encoded *** cNN captures the effects of building geometry on energy predictions better than ANN and cBML approaches,it is an attractive choice for early-stage energy design.

关键词： Energy performance ANN cNN component-based ML Deep learning Autoencoders

Genotypic diversity of a dominant c_(4) grass across a long-term fire frequency gradient

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Journal of Plant Ecology 2013年第6期6卷 448-458页

作者： cynthia c.chang Melinda D.smith Department of Ecology and Evolutionary Biology Yale UniversityNew HavenCT 06511USA Department of Biology University of WashingtonSeattleWA 98195USA Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Aims and Methods Diversity-disturbance research has focused on community diversity,but disturbance frequency could impact diversity within species as well,with important consequences for community diversity and ecosystem *** examined patterns of genetic diversity of a dominant grass species,Andropogon gerardii,in native North American tallgrass prairie sites located in eastern Kansas that have been subjected to a gradient of fire frequency treatments(burned every 1,2,4 or 20 years)since the *** addition,we were able to assess the relationships between genetic diversity of ***,species diversity and productivity across this range of fire *** Findings We found no significant relationships between genetic diversity of *** at the local scale(1 m^(2) plot level)and disturbance frequency(burned 2 to 32 times over a 38-year period).However,at the site level(*** all plots sampled within a site,~100 m^(2))there were differences in genotype richness and composition,as well as genomic dissimilarity among individuals of *** richness was greatest for the site burned at an intermediate(4-year)frequency and lowest for the infrequently(20-year)burned *** addition,genotypes found in the frequently burned sites were more similar from each other than expected by random chance than those found in the infrequently burned *** composition of *** was not significantly different between the frequently burned sites(annual vs.2 year)but did differ between frequently burned and infrequently burned sites(1 and 2 year vs.4 and 20 year,etc.).Together,these results suggest site-level ecological sorting of genotypes in intact prairie across a broad gradient of disturbance frequencies,likely driven by alterations in environmental *** fire promotes the abundance of dominant grass species,reduces plant community diversity and impacts ecosystem processes such as *** study suggests that

关键词： Andropogon gerardii disturbance frequency genetic relatedness genetic-species diversity relationship genotype richness intermediate disturbance hypothesis productivity tallgrass prairie

Speciation with gene flow via cycles of isolation and migration:insights from multiple mangrove taxa

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National Science Review 2019年第2期6卷 275-288页

作者： Ziwen He Xinnian Li Ming Yang Xinfeng Wang cairong Zhong norman c.Duke chung-I Wu Suhua Shi State Key Laboratory of Biocontrol Guangdong Key Lab of Plant Resources Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education InstitutesSchool of Life Sciences Sun Yat-Sen University Department of Ecology and Evolution University of Chicago cAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences Hainan Dongzhai Harbor National Nature Reserve Administration centre for Tropical Water and Aquatic Ecosystem Research James Cook University

Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca,narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn(m > 1) species after n cycles.

关键词： speciation gene flow allopatry geographical isolation mangrove