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化学教学 1982年第4期 30-32+26页

作者： iain m.duncan,黄经昌英

伸展在晶格内的离子键很强,因此从晶格中移走离子是困难的。由于这个原因,离子型化合物具有较高的熔点和沸点。存在于共价型固体或液体中的分子间的作用力没有这样强(除1～2例外),使分子聚集在一起的作用力布遍于固体中也是不强的。考... 详细信息

伸展在晶格内的离子键很强,因此从晶格中移走离子是困难的。由于这个原因,离子型化合物具有较高的熔点和沸点。存在于共价型固体或液体中的分子间的作用力没有这样强(除1～2例外),使分子聚集在一起的作用力布遍于固体中也是不强的。考虑下列的气化热:

关键词：范德华力化学键单元程序分子间作用电负性差水分子

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自学单元程序教材介绍:化学键(一)

化学教学 1982年第3期 35-37页

作者： iain m.duncan ,黄经昌

本文译自“Higher Grade Chemistry”一书的第六单元。该书系供英国中学高年级学生在学过普通水平的化学以后选修或自学之用。每一单元的内容系针对一专题循序渐进地介绍事实材料或实验数据,采用图、文、表,使抽象的概念形象化、理论具... 详细信息

本文译自“Higher Grade Chemistry”一书的第六单元。该书系供英国中学高年级学生在学过普通水平的化学以后选修或自学之用。每一单元的内容系针对一专题循序渐进地介绍事实材料或实验数据,采用图、文、表,使抽象的概念形象化、理论具体化。在每一段之后,安排思考题数则,用以加深理解和运用知识,最后概括出结论。每一单元的结尾附有问题解答,以俾自学者及时校对或纠正错误。

关键词：化学键离子键单元程序电负性差气态原子离子性气态离子电离能共价性

Transcriptional and Post-transcriptional Gene Regulation by Long Non-coding RNA

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Genomics, Proteomics & Bioinformatics 2017年第3期15卷 177-186页

作者： iain m.Dykes Costanza Emanueli School of Clinical Sciences University of Bristol National Heart and Lung Institute Imperial College London

Advances in genomics technology over recent years have led to the surprising discovery that the genome is far more pervasively transcribed than was previously appreciated. much of the newly-discovered transcriptome appears to represent long non-coding RNA （lncRNA）, a heteroge- neous group of largely uncharacterised transcripts. Understanding the biological function of these molecules represents a major challenge and in this review we discuss some of the progress made to date. One major theme of lncRNA biology seems to be the existence of a network of interactions with microRNA （miRNA） pathways, lncRNA has been shown to act as both a source and an inhi- bitory regulator of miRNA. At the transcriptional level, a model is emerging whereby lncRNA bridges DNA and protein by binding to chromatin and serving as a scaffold for modifying protein complexes. Such a mechanism can bridge promoters to enhancers or enhancer-like non-coding genes by regulating chromatin looping, as well as conferring specificity on histone modifying com- plexes by directing them to specific loci.

关键词： Long non-coding RNA microRNA Transcriptional regulation Epigenetics Post-transcriptionalregulation

Flow hydrodynamics drive effective fish attraction behaviour into slotted fishway entrances

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Journal of Hydrodynamics 2023年第4期35卷 782-802页

作者： maryam Farzadkhoo Richard T.Kingsford iain m.Suthers Stefan Felder Water Research Laboratory School of Civil and Environmental EngineeringThe University of New South WalesSydneyAustralia Centre for Ecosystem Science School of BiologicalEarth and Environmental SciencesThe University of New South WalesSydneyAustralia

Effective fishways rely on attracting fish,utilising the natural rheotactic behaviour of fish to orient into an attraction flow near the *** the critical importance of attraction,understanding of the hydrodynamics of vertical slot entrances in relation to fish behaviour remains ***,hydrodynamic measurements of flows at slotted fishway entrances were experimented with two different designs,two velocities,three water depths,and two fish species,silver perch(Bidyanus bidyanus)and Australian bass(Percalates novemaculeata).Fish behaviours were tracked in relation to hydrodynamic measures of three-dimensional velocity and turbulent kinetic energy(TKE).There were distinct differences in the attraction flow between entrance designs,irrespective of velocity and water depth.A plain slotted entrance produced a more symmetric flow in the centre of the flume,causing fish to approach the entrance by skirting the core of the attraction jet flow and areas of high *** contrast,streamlined slotted entrance design resulted in an asymmetric attraction flow which guided fish along the wingwall towards the slotted entrance,improving attraction for both *** were clear patterns in swimming trajectories for silver perch,swimming along the sidewalls of the observation zone towards the entrance,but Australian bass were less predictable,using random routes on their way to the slotted *** species preferred areas of low turbulence(TKEm^(2)/s^(2)).This work has important implications for design of vertical slotted entrance systems.

关键词： Attraction jet flow fish behaviour fish swimming trajectories turbulent kinetic energy(TKE) Australian native fish

Convergence Detection in Direct Simulation monte Carlo Calculations for Steady State Flows

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Communications in Computational Physics 2011年第9期10卷 807-822页

作者： Jonathan m.Burt iain D.Boyd U.S.Air Force Research Laboratory Wright-Patterson Air Force BaseOH 45433USA Department of Aerospace Engineering University of Michigan1320 Beal AvenueAnn ArborMI 48109USA

A new criterion is presented to detect global convergence to steady state,and to identify local transient characteristics,during rarefied gas flow simulations performed using the direct simulation monte Carlo(DSmC)*** deterministic computational fluid dynamics(CFD)schemes,DSmC is generally subject to large statistical scatter in instantaneous flow property evaluations,which prevents the use of residual tracking procedures as are often employed in CFD ***,reliable prediction of the time to reach steady state is necessary for initialization of DSmC sampling *** currently used in DSmC to identify steady state convergence are usually insensitive to weak transient behavior in small regions of relatively low density or recirculating *** proposed convergence criterion is developed with the goal of properly identifying such weak transient behavior,while adding negligible computational expense and allowing simple implementation in any existing DSmC *** of the proposed technique over existing convergence detection methods are demonstrated for representative nozzle/plume expansion flow,hypersonic blunt body flow and driven cavity flow problems.

关键词： monte Carlo methods particle methods direct simulation monte Carlo

Analytical data supporting the“theoretical”postmortem redistribution factor(F_(t)):a new model to evaluate postmortem redistribution

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Forensic Sciences Research 2016年第1期1卷 33-37页

作者： iain m.mcIntyre Forensic Toxicology Laboratory Department of the Medical ExaminerSan DiegoCAUSA

The concepts of postmortem redistribution(PmR,F)factor,and“theoretical”PmR(Ft)–based upon a drug’s characteristic L/P ratio–have been defined to express the direct relationship between postmortem peripheral blood and the corresponding antemortem whole-blood *** paper applies recent data describing liver/peripheral blood(L/P)ratios for many commonly detected drugs to assess these models,and provide a ranking of drugs’propensity for(and degree of)PmR.

关键词： Forensic science forensic pathology peripheral blood liver antemortem theoretical postmortem redistribution factor(F_(t))

红色荧光定量分析法评价釉质早期龋的临床研究

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华西口腔医学杂志 2010年第3期28卷 278-281页

作者：尹伟冯岩胡德渝 Roger P.Ellwood iain A.Pretty 口腔疾病研究国家重电实验室四川大学四川成都610041 福建医科大学附属口腔医院预防科福建福州350002 Dental Health Unit The University of ManchesterManchester M15 6SHUK

目的采用定量光导荧光(QLF)技术的红色荧光分析法检测釉质早期龋,并监测含氟牙膏促进早期龋再矿化的效果,评价该技术诊断早期龋的能力。方法选择有上颌前牙光滑面釉质早期龋的96名小学生为研究对象,指导其在6个月的时间内使用含氟牙膏(... 详细信息

目的采用定量光导荧光(QLF)技术的红色荧光分析法检测釉质早期龋,并监测含氟牙膏促进早期龋再矿化的效果,评价该技术诊断早期龋的能力。方法选择有上颌前牙光滑面釉质早期龋的96名小学生为研究对象,指导其在6个月的时间内使用含氟牙膏(氟离子质量分数为0.145%)刷牙。分析基线和6个月后的上颌前牙光滑面荧光图像,获得红色荧光变量(包括荧光面积Ar、平均荧光量△R、荧光总量R),将其与绿色荧光变量(包括荧光面积Aw、平均荧光损失量△F、荧光损失总量△Q)进行比较,并通过配对t检验评价使用含氟牙膏后龋损的变化情况。结果红色荧光变量Ar、△R、lgR与对应的绿色荧光变量Aw、△F、lg△Q的Pearson相关系数分别为0.89、0.54、0.72(P<0.05),具有高度相关性。使用含氟牙膏6个月后,红色和绿色荧光变量均较基线明显降低,其差异有统计学意义(P<0.05)。结论采用QLF技术的红色荧光分析法能够评价釉质早期龋的严重程度,并纵向监测病变,适用于评价龋损防治措施的效果。

关键词：定量光导荧光红色荧光绿色荧光早期龋

Advancements in prokaryotic systematics and the role of Bergey's International Society for microbial Systematics in addressing challenges in the meta-data era

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National Science Review 2024年第7期11卷 292-304页

作者： Jian-Yu Jiao Rashidin Abdugheni Dao-Feng Zhang Iftikhar Ahmed mukhtiar Ali maria Chuvochina Svetlana N.Dedysh Xiuzhu Dong markus G?ker Brian P.Hedlund Philip Hugenholtz Kamlesh Jangid Shuang-Jiang Liu Edward R.B.moore manik Prabhu Narsing Rao Aharon Oren Ramon Rossello-mora Bhagwan Narayan Rekadwad Nimaichand Salam Wensheng Shu iain C.Sutcliffe Wee Fei Aaron Teo martha E.Trujillo Stephanus N.Venter William B.Whitman Guoping Zhao Wen-Jun Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) School of Life Sciences Sun Yat-Sen University State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and Geography Chinese Academy of Sciences Jiangsu Province Engineering Research Center for marine Bio-resources Sustainable Utilization&College of Oceanography Hohai University National Culture Collection of Pakistan(NCCP) Land Resources Research Institute(LRRI) National Agricultural Research Centre(NARC) The University of Queensland School of Chemistry and Molecular Biosciences Australian Centre for Ecogenomics Winogradsky Institute of microbiology Research Center of BiotechnologyRussian Academy of Sciences State Key Laboratory of microbial Resources Institute of Microbiology Chinese Academy of Sciences Leibniz Institute DSmZ–German Collection of microorganisms and Cell Cultures School of Life Sciences University of Nevada Nevada Institute of Personalized medicine University of Nevada Bioenergy Group MACS Collection of Microorganisms Agharkar Research Institute State Key Laboratory of microbial Technology Shandong University Department of Infectious Disease Institute for Biomedicine and Culture Collection University of Gothenburg(CCUG) Institute for BiomedicineSahlgrenska AcademyUniversity of Gothenburg Instituto de Ciencias Aplicadas Facultad de Ingeniería Universidad Autónoma de Chile The Alexander Silberman Institute of Life Sciences The Edmond J.Safra Campus The Hebrew University of Jerusalem marine microbiology Group Department of Animal and Microbial Biodiversity Mediterranean Institute for Advanced Studies(IMEDEA CSIC-UIB) microbeAI Lab Division of Microbiology and Biotechnology Yenepoya Research Centre Yenepoya(Deemed to be University) National Agri-Food Biotechnology Institute Institute of Ecological Science Sch

Prokaryotes are ubiquitous in the biosphere, important for human health and drive diverse biological and environmental processes. Systematics of prokaryotes, whose origins can be traced to the discovery of microorganisms in the 17th century, has transitioned from a phenotype-based classification to a more comprehensive polyphasic taxonomy and eventually to the current genome-based taxonomic *** transition aligns with a foundational shift from studies focused on phenotypic traits that have limited comparative value to those using genome sequences. In this context, Bergey's manual of Systematics of Archaea and Bacteria(BmSAB) and Bergey's International Society for microbial Systematics(BISmiS) play a pivotal role in guiding prokaryotic systematics. This review focuses on the historical development of prokaryotic systematics with a focus on the roles of BmSAB and BISmiS. We also explore significant contributions and achievements by microbiologists, highlight the latest progress in the field and anticipate challenges and opportunities within prokaryotic systematics. Additionally, we outline five focal points of BISmiS that are aimed at addressing these challenges. In conclusion, our collaborative effort seeks to enhance ongoing advancements in prokaryotic systematics, ensuring its continued relevance and innovative characters in the contemporary landscape of genomics and bioinformatics.

关键词： prokaryotic systematics Bergey's manual of Systematics of Archaea and Bacteria (BmSAB) Bergey's International Society for microbial Systematics (BISmiS) meta-data era

The role of ultrasonic bat detectors in improving inventory and monitoring surveys in Vietnamese karst bat assemblages

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Current Zoology 2009年第5期55卷 327-341页

作者： Neil m.FUREY iain J.mACKIE Paul A.RACEY School of Biological Sciences University of AberdeenAberdeen

Bats account for 30% of mammal diversity in SE Asia and are potential bioindicators of wider biodiversity impacts resulting from habitat loss and climate change. As existing sampling techniques in the region typically fail to record bats that habitually fly in open areas and at higher altitudes, current inventory efforts are less than comprehensive. Acoustic sampling with bat detectors may help to overcome these limitations for insectivorous bats, but has yet to be tested in mainland SE Asia. To do so, we sampled bats while simultaneously recording the echolocation calls of insectivorous species commuting and foraging in a variety of karst habitats in north Vietnam. monitoring of cave-dwelling bats was also undertaken. Discriminant function analysis of 367 echolocation calls produced by 30 insectivorous species showed that acoustic identification was feasible by correctly classifying 89. 1% of calls. In all habitats, acoustic sampling and capture methods recorded significantly more species each night than capture methods alone. Capture methods consequently failed to record 29% （ten spp. of aerial insectivores） of the bat fauna in commuting and foraging habitats and 11% （two spp. ） of that in our cave sample. Only four of these species were subsequently captured following significantly greater sampling effort. This strongly suggests that acoustic methods are indispensable for maximizing bat inventory completeness in SE Asia. As accurate inventories and monitoring are essential for effective species conservation, we recommend the inclusion of acoustic sampling in future studies of bat assemblages across the region [ Current Zoology 55 （5）： 327 - 341, 2009].

关键词： Bats Echolocation Inventory completeness Karst Vietnam

定量光导荧光技术评价含氟牙膏抑制早期龋损效果的临床研究

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华西口腔医学杂志 2008年第6期26卷 607-610页

作者：冯岩尹伟胡德渝 Yunpo Zhang iain A. Pretty Roger P. Ellwood 福建医科大学附属口腔医院预防科福建福州350002 四川大学华西口腔医学院口腔预防医学教研室四川成都610041 Colgate-Palmolive Company NY 08854 USA Dental Health Unit Manchester Dental School Manchester M156SH UK

目的评价定量光导荧光技术(QLF)用于纵向监测光滑面早期龋损矿物质含量变化的能力及用于评价不同氟化物抑制早期龋损效果差异的可能性。方法选取305名11～14岁上颌前牙有早期光滑面龋的中小学生,随机分为NaF组、mFP组和不含氟组,分别采... 详细信息

目的评价定量光导荧光技术(QLF)用于纵向监测光滑面早期龋损矿物质含量变化的能力及用于评价不同氟化物抑制早期龋损效果差异的可能性。方法选取305名11～14岁上颌前牙有早期光滑面龋的中小学生,随机分为NaF组、mFP组和不含氟组,分别采用含NaF的牙膏、含Na2PO3F的牙膏(氟浓度均为1450mg/L)和不含氟的牙膏刷牙。拍摄受检者上颌前牙光滑面早期龋损基线、刷牙后3个月和6个月时的QLF照片并保存。使用软件QLF2.00g对病损进行分析,界定病损范围,得出每次检查的△F(荧光损失)、Area(病损面积)和△Q(总荧光损失量)。结果296名(97.05%)受检者完成了整个研究。QLF检查结果显示,3个月时,296名受检者上颌前牙光滑面早期龋损均出现不同程度的好转,3组光滑面早期龋损Area、△F和lg△Q的变化均无统计学差异(P>0.05);6个月时,296名受检者上颌前牙光滑面早期龋损均较基线时出现明显的好转,NaF组、mFP组光滑面早期龋损Area、△F和lg△Q的变化有统计学差异(PmFP组之间无统计学差异(P>0.05)。结论QLF作为一种定量诊断方法,能够用于纵向病变跟踪监测和评价不同龋病干预措施效果。

关键词：定量光导荧光技术含氟牙膏早期龋光滑面