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Enhanced and asymmetric signatures of hybridization at climatic margins: Evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-Feng Huang clive t.Darwell Yan-Qiong Peng CAS Key Laboratory of tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China National Center for Genetic Engineering and Biotechnology(BIOtEC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene *** of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales.

关键词： Hybridization Heterospecific visitation Fig Pollinator wasp Asymmetric gene flow

Geochemistry of Radiolarian Cherts from a Late Devonian Continental Margin Basin,Loei Fold Belt,Indo-China terrane

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Journal of Earth Science 2017年第1期28卷 29-50页

作者： Hathaithip thassanapak Mongkol Udchachon clive Burrett Qinglai Feng Applied Paleontology and Biostratigraphy Research Unit Department of BiologyFaculty of ScienceMahasarakham University Paleontological Research and Education Center Mahasarakham University School of Physical Sciences University of Tasmania State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

More than 42 species of well-preserved Upper Devonian radiolarians have been obtained from cherts and siliceous shales in four sections(Chom Noi, Phu Kham Phe(P), Phu Kham Phe(C) and Pha Samyod) from the NE thailand sector of the Loei fold belt, Indochina terrane. they include Ceratoikiscum sp. cf. planistellare Foreman, Helenifore laticlavium Nazarov & Ormiston, Astroentactinia sp. cf. paronae(Hinde), Stigmosphaerostylus herculea(Foreman), S. pusilla(Hinde), S. cf. vulgaris(Won), trilonche davidi(Hinde), t. echinata(Hinde), t. elegans Hinde, t. hindea(Hinde), t. palimbola(Foreman), t. vetusta Hinde, Polyentactinia polygonia Foreman, Spongentactinella sp. cf. windjanensis Nazarov, Archocyrtium sp.?, Palaeoscenidium sp., triaenosphaera sp., and others. Radiolarian faunas from these sections indicate a range from lower Frasnian to Famennian. Analyses of rare earth, trace and major elements suggest that the Upper Devonian chert and siliceous successions from Loei were deposited in a continental margin environment near to a volcanic arc. these successions contain distinctive weak negative Ce anomalies with strong positive Eu anomalies which differ from Upper Devonian cherts reported from northern thailand, the truong Son fold belt(Laos) and from South China. Negative Ce anomalies and low to moderate Lan/Cen ratios imply proximity between the Chom Noi and Phu Kham Phe(C), which were deposited in more distal parts of the depositional basin than the Pha Samyod and Phu Kham Phe(P) samples. Most of the Pha Samyod and Phu Kham Phe(P) samples exhibit high continental-derived trace element levels including Cr, Zr, Hf, Rb, th and in part V, which supports close proximity to terrigenous sources. Paleozoic stratigraphic sequences of the Loei fold belt and geochemical results suggest that the Upper Devonian deep marine sequences in the Loei fold belt were deposited within a rifted, continental-margin basin, possibly a back-arc basin and not in a large oceanic basin as has been prev

关键词： radiolarians paleogeography paleoenvironments REE trace elements tectonics

Middle triassic Radiolarians from Cherts/Siliceous Shales in an Extensional Basin in the Sukhothai Fold Belt,Northern thailand

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Journal of Earth Science 2017年第1期28卷 9-28页

作者： Hathaithip thassanapak Mongkol Udchachon Qinglai Feng clive Burrett Applied Paleontology and Biostratigraphy Research Unit Department of Biology Faculty of Science Mahasarakham University Mahasarakham 44150 Thailand State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Paleontological Research and Education Center Mahasarakham University Mahasarakham 44150 Thailand School of Physical Sciences University of Tasmania Hobart Tasmania 7001 Australia

More than thirty species of radiolarians are described from maroon chert and siliceous shales from the Den Chai and Santisuk sections in the east of the Sukhothai fold belt. the fauna obtained from Den Chai comprises Muelleritortis cochleata cochleata, M. cochleata tumidospina, M. expansa, triassocampe deweveri, t. coronata, t. scalaris, Annulotriassocampe companilis, A. multisegmantatus, A. sulovensis, Pseudostylosphaera coccostyla coccostyla, P. imperspicua, Canoptum inornatus, C. levis, Corum kraineri, Spongoserrula rarauana, Orbiculiforma karnica and others. the assemblage may be correlated with those reported in the Fang-Chiang Dao and Lumphun areas in the north of thailand and in the ChangningMenglian belt of western Yunnan, South China and suggests a late Ladinian（Middle triassic） age. the radiolarian fauna from the Santisuk Section comprises Muelleritortis cochleata cochleata, M. sp., Striatotrissocampe nodosoannulata, triassocampe. deweveri, t. sp., Pseudogodia？ sp., Pseudostylosphaera coccostyla coccostyla, Archaeocenosphera sp., Annulotriassocampe multisegmantis, Pseudostylosphaera sp., and others which indicates a late Ladinian age. Middle triassic radiolarian chert and siliceous shale from Den Chai and Santisuk are interpreted as having been deposited in an extensional continental margin within the Sukhothai fold belt and not in the Devonian–Permian back-arc basin of the Nan suture. these deep marine sequences were deposited in a subsiding continental margin in the Lampang-Phrae Basin. We consider these sequences to be part of the Hong Hoi Formation（Anisian–Ladinian） of the Lampang Group which, in turn, may be compared to the Choushui Formation and other associated Middle triassic formations in the Simao Basin of South China.

关键词： triassic radiolarians Sukhothai fold belt Nan suture thailand.

Gestation-specific reference intervals for fetal cardiac Doppler indices from 12 to 40 weeks of gestation

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Open Journal of Obstetrics and Gynecology 2013年第1期3卷 97-104页

作者： Rajeswari Parasuraman clive Osmond David t. Howe MRC Lifecourse Epidemiology Unit Southampton General Hospital Southampton UK Wessex Maternal and Fetal Medicine unit Princess Anne Hospital Southampton UK

We aimed to establish gestation age specific reference intervals for Doppler indices of fetal cardiac function from 12 to 40 weeks of pregnancy. In a cross-sectional observational study of singleton pregnancies, examinations were performed in 221 women evenly distributed across each week of pregnancy. Blood flow through the four cardiac valves was examined with Doppler. For the atrioventricular valves, velocity and duration of early (E) and atrial (A) waves and the interval (a) between E/A complexes was recorded. For the outflow valves, the duration (b), peak and average velocity of flow in systole was measured. Myocardial performance index (MPI) was calculated as (a - b)/b. Outlet valve diameters were measured and cardiac outputs were calculated. Gestation age specific ranges were constructed for all these parameters. We demonstrated that the cardiac output, peak systolic and time-averaged velocity increase with advancing gestation. However the MPI and E/A ratios show little change across gestation. Fetal cardiac physiology can be studied and Doppler indices reliably measured as early as the late first trimester of pregnancy. Establishing gestation age specific ranges for various cardiac indices throughout pregnancy will help the study of development of fetal cardiac function.

关键词： Cardiac Doppler Fetal Gestation Age Reference Range Ultrasound

Leaflet Movement of Robinia pseudoacacia in Response to a Changing Light Environment

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Journal of Integrative Plant Biology 2007年第4期49卷 419-424页

作者： Cheng-Cheng Liu clive V. J. Welham Xian-Qiang Zhang Ren-Qing Wang Institute of Ecology and Biodiversity School of Life Sciences Shandong University Jinan 250100 China Forest Ecosystem Management Simulation Group Department of Forest Sciences University of British Columbia Vancouver BC V6T 1Z4 Canada

Diurnal and nocturnal leaflet movement of black locust （Robinia pseudoacacia L.） was investigated under three light schemes： 100% natural irradiance, 50% shading, and 90% shading. Changes in leaf mid-vein angle were described by measurements of two planes：（i） β, the angle formed by the bottom of the petiolule and its relation to the horizontal plane; and （ii） θ, the angle between the petiolule and the main leaflet vein. the two highest light regimens had a significant effect on β. Variation in β tends to make the leaflet more erect, thereby minimizing any negative impact of high irradiance on leaf lamina. Light-dark rhythms induced variation in θ （termed nyctinastic movement）. Nyctinastic movement is important during the low light levels experienced by leaflets in early morning and late afternoon. At low light levels, the leaflet stopped nyctinastic movement and θ was fixed at an angle that may have enabled the leaf lamina to maximize light interception. After the light-dark cycle was reestablished, nyctinastic movement was restored. taken together, our results suggest that irradiance induces variation in β leading to diurnal leaflet movement （diaheliotropism）, whereas the light-dark cycle influences θ, which results in nocturnal leaflet movement. Both angles are important for describing patterns of leaf movement in R. pseudocacia.

关键词： heliotropism leaflet movement mid-vein angle nyctinastic movement Robinia pseudoacacia

An Approach to the Core Structure of CP-225,917

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有机化学 2003年第Z1期23卷 45-46页

作者： ZHOU Zhi-Ming Derrick L. J. clive Pharmaceutical Center Beijing Institute of Technology Beijing 100081 Department of Chemistry University of Alberta Edmonton Alberta Canada T6G 2G2

　　the complex natural product CP-225, 917 (1), which is an inhibitor of Ras fanesyl tranferase,[1～3] has at tracted much attention of several groups for its total synthesis. Our own approach is based on siloxy Cope rearrangement, which could be accomplished thermally in very good yield (99%) to from 10 to 11,[4] a model compound lacking the side arms of the natural product. Its synthetic route from 6 is shown.……

关键词： natural product total synthesis model compound

Comparison of the reproducibility of 2D doppler and 3D StIC in the measurement of fetal cardiac output

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Open Journal of Obstetrics and Gynecology 2011年第4期1卷 163-167页

作者： Rajeswari Parasuraman clive Osmond David t. Howe 不详

Objectives: two methods have been described to assess fetal cardiac output (CO). It has usually been calculated by using 2D ultrasound to measure the diameter of outflow valves and Doppler ultrasound to measure flow velocity through the valves. Recently CO has been assessed using 3D spatio-temporal image correlation (StIC) to measure stroke volume. We aimed to compare the reproducibility of these techniques. Methods: In 27 women with singleton pregnancies, examinations were performed in three gestational age groups: 13 - 15, 19 - 21 and >30 weeks of gestation. Each mother was scanned once. Using 2D pulsed wave Doppler the duration of flow and average flow velocity in systole were measured through aortic and pulmonary valves. We averaged values from three consecutive Doppler complexes. the outlet valve diameters were measured and the cardiac output was calculated for each valve. the measurements were repeated to assess reproducibility. In the same women, we acquired StIC volumes of the fetal heart. the volume measurements were made using the 3D Slice method by one observer. Using 2 mm slices the circumference of the ventricles was traced at the end of systole and diastole to calculate ventricular volume before and after contractions to calculate stroke volume and hence cardiac output. the measurements were repeated to assess reproducibility. Results: the root mean square difference of log (CO) of repeat measurements ranged between 0.12 and 0.21 using Doppler compared to 0.7 to 1.47 using StIC. the differences in reproducibility reached statistical significance for both sides of the heart at all but one gestation. Conclusions: We found that Doppler assessment of fetal cardiac output was more reproducible than measurement using StIC.

关键词： Cardiac Output Fetal StIC 2D Doppler Ultrasound

the Definitive Guide to How Computers Do Math: Featuring the Virtual DIY Calculator 1st edition

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Biometrics and wing molt in White-winged Black tern (Chlidonias leucopterus) in north-west Australia

2005年

作者： clive “MAX” Maxfield Alvin Brown

ISBN: (数字)9780471741978

ISBN: (纸本)9780471732785

the Basics of Computer Arithmetic Made Enjoyable and Accessible-with a Special Program Included for Hands-on Learning "the combination of this book and its associated virtual computer is fantastic! Experience over the last fifty years has shown me that there's only one way to truly understand how computers work; and that is to learn one computer and its instruction set-no matter how simple or primitive-from the ground up. Once you fully comprehend how that simple computer functions, you can easily extrapolate to more complex machines."-Fred Hudson, retired engineer/scientist "this book-along with the virtual DIY Calculator-is an incredibly useful teaching and learning tool. the interesting trivia nuggets keep you turning the pages to see what's next. Students will have so much fun reading the text and performing the labs that they won't even realize they are learning."-Michael Haghighi, Chairperson of the Business and Computer Information Systems Division, Calhoun Community College, Alabama "At last, a book that presents an innovative approach to the teaching of computer architecture. Written with authority and verve, witty, superbly illustrated, and enhanced with many laboratory exercises, this book is a must for students and teachers alike."-Dr. Albert Koelmans, Lecturer in Computer Engineering, University of Newcastle upon tyne, UK, and the 2003 recipient of the EASIt-Eng. Gold Award for Innovative teaching in Computer Engineering Packed with nuggets of information and tidbits of trivia, How Computers Do Math provides an incredibly fun and interesting introduction to the way in which computers perform their magic in general and math in particular. the accompanying CD-ROM contains a virtual computer/calculator called the DIY Calculator, and the book's step-by-step interactive laboratories guide you in the creation of a simple program to run on your DIY Calculator. How Computers Do Math can be enjoyed by non-technical individuals; students of computer science, elec

关键词： Computer science

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Chinese Birds 2013年第4期4卷 306-313页

作者： Peter J. FULLAGAR Michael J. DAWKINS clive D. t. MINtON Unit 1/11 Joy Cummings Place Belconnen ACT 2617 Australia 15 the Boulevarde Wy Yung Victoria 3875 Australia 165 Dalgetty Road Beaumaris Victoria 3193 Australia

We analyze morphometrics from a sample of 276 White-winged Black tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this species yet reported from Australia. When comparing juveniles with adults, only wing length and body mass differed significantly; however, juveniles were still easily recognized by plumage and wing molt as late as March. there was little evidence of any dramatic weight gain in adults before their northward migration. No morphological characteristic distinguishing sex was found. We confirmed that terns caught in this study did not appear to differ morphologically from those of the western palearctic populations. We describe wing molt based on data from 354 individuals captured and banded in Australia over 28 years. Wing molt proceeds in much the same way as found in other small terns.

关键词： White-winged Black tern morphometrics wing molt Australia feeding roosting