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DIFFUSION cOUPLE BETWEEN hIGhSTRENGTh WEAR-RESISTING ALUMINUM BRONZE AND MAchINING TOOLS MATERIALS

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中国有色金属学会会刊：英文版 1999年第1期9卷 8-10,10+12+9+11页

作者： Li, Yuanyuan Zhang, Datung Ngai Tungwai, leo Xia, Wei Long, Yan South china Univ of Technology Guangzhou China

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ＩＮＴＲＯＤＵＣＴＩＯＮＡｌｕｍｉｎｕｍｂｒｏｎｚｅｉｓａｎｉｍｐｏｒｔａｎｔｅｎｇｉｎｅｅｒｉｎｇｍａｔｅｒｉａｌ．Ｉｔｓｅｘｃｅｌｅｎｔｐｈｙｓｉｃａｌ，ｍｅｃｈａｎｉｃａｌ，ａｎｔｉｃｏｒｏｓｉｏｎａｎｄｗｅａｒｒｅｓｉｓｔｉｎｇｐｒｏｐ...

关键词： wear resistance aluminum bronze tool materials diffusion

Regulation of the SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE genes/microRNA 156 Module by the homeodomain Proteins PENNYWISE and POUND-FOOLISh in Arabidopsis

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Molecular Plant 2011年第6期4卷 1123-1132页

作者： Shruti Lal leo Bryan Pacis harley M.S. Smith Genetics Genomics and Bioinformatics Graduate Program University of California Riverside CA 92521 USA center for Plant cell Biology Institute of Integrative Genome Biology Department of Botany and Plant Sciences University of California Riverside CA 92521 USA

The morphology of inflorescences is regulated in part by the temporal and spatial events that regulate flower specification. In Arabidopsis, an endogenous flowering time pathway mediated by a subset of SQUAMOSA PROMOTER- BINDING PROTEIN-LIKE （SPL） transcription factors, including SPL3, SPL4, and SPL5, function to specify flowers by activating floral meristem identity genes. During shoot development, SPL3, SPL4, and SPL5 are post-transcriptionally regulated by microRNA156 （miR156）. The photoperiod regulated florigenic signal, FLOWERING LOcUS T （FT）, promotes floral induction, in part by activating SPL3, SPL4, and SPL5. In turn, these SPLs function in parallel with FT to specify flower meristems. Two related BELLl-like homeobox genes PENNYWISE （PNY） and POUND-FOOLISh （PNF） expressed in the shoot apical meristem are absolutely required for the specification of floral meristems. Genetic studies show that the floral specification function of FT depends upon PNYand PNF; however, the interplay between these homeodomain proteins and SPLs is not known. In this manuscript, we show that the photoperiodic floral induction of SPL3, SPL4, and SPL5 is dependent upon PNY and PNE Further, PNY and PNF also control SPL3, SPL4, and SPL5 expression by negatively regulating miR156. Lastly, ectopic expres- sion of SPL4 partially rescues the pny pnf non-flower-producing phenotype, while overexpression of SPL3 or SPL5 in pny pnf plants was unable to restore flower specification. These results suggest that：（1） SPL3, SPL4, and SPL5 function is dependent upon PNY and PNF, or （2） expression of multiple SPLs is required for floral specification in pny pnf plants.

关键词： Development meristem homeodomain flowering microRNA.

Visual ＂playback＂ of colorful signals in the field supports sensory drive for signal detectability

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current Zoology 2018年第4期64卷 493-498页

作者： Alex R. GUNDERSON leo J. FLEIShMAN Manuel LEAL Department of Integrative Biology University of California Berkeley CA 94720 USA Department of Biology Union College Schenectady NY 12308 USA Division of Biological Sciences University of Missouri 105 Tucker Hall Columbia MO 65211 USA

colorful visual signals are important systems for investigating the effects of signaling environ ments and receiver physiology on signal evolution as predicted by the sensory drive hypothesis. Support for the sensory drive hypothesis on color signal evolution is mostly based on document ing correlations between the properties of signals and habitat conditions under which the signals are given （i.e., a correlational approach） and less commonly on the use of mathematical models that integrate representations of visual environments, signal properties, and sensory systems （i.e., a functional approach）. here, we used an experimental approach in the field to evaluate signal efficacy of colorful lizard throat fans called dewlaps that show geographic variation in the lizard Anolis cristatellus. We used a remote controlled apparatus to display ＂fake dewlaps＂ to wild lizards to test for adaptive divergence in dewlap brightness （i.e., perceived intensity） among populations in situ. We found evidence of local adaptation in dewlap brightness consistent with the sensory drive hypothesis. Specifically, dewlaps that had the brightness characteristics of local lizards were more likely to be detected than those with the brightness characteristics of nonlocal lizards. Our findings indicate that simplified mathematical representations of visual environments may allow robust estimates of relative detectability or conspicuousness in natural habitats. We have shown the feasibility of evaluating color signal efficacy experimentally under natural conditions and dem onstrate the potential advantages of presenting isolated components of signals to an intended re ceiver to measure their contribution to signal function.

关键词： Anolis color signal sensory drive signal evolution

Intraepithelial lymphocytes: bystanders or causative factors in functional gastrointestinal disorders?

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cellular & Molecular Immunology 2021年第7期18卷 1620-1621页

作者： Giuseppe Losurdo Domenico Piscitelli Enzo Ierardi Alfredo Di leo Section of Gastroenterology Department of Emergency and Organ TransplantationUniversity of BariBariItaly Ph.D.course in Organs and Tissues Transplantation and cellular Therapies Department of Emergency and Organ TransplantationUniversity of BariBariItaly Section of Pathology Department of Emergency and Organ TransplantationUniversity of BariBariItaly

Intraepithelial lymphocytes(IELs)are immune cells located in the epithelium of the mucosal layer of the gastrointestinal tract that typically show a cD3-positive *** are T lymphocytes that are involved in the primary immune response to several luminal antigens,such as food proteins and infectious *** this reason,their increase may be pathogenetic in several diseases,the most important being celiac ***,an increase above 25 IELs/100 enterocytes in the duodenum,which is considered the cutoff value for celiac disease,may occur in several conditions,such as nonceliac gluten sensitivity,food allergy,helicobacter pylori(***)infection,gastroenteritis,and even irritable bowel syndrome(IBS).Therefore,the generic term“microscopic enteritis”or“duodenal lymphocytosis”has been proposed for this condition.

关键词： lymphocytes gastrointestinal epithelium

Galactic center research:manifestations of the central black hole

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Research in Astronomy and Astrophysics 2012年第8期12卷 995-1020页

作者： Mark R.Morris leo Meyer Andrea M.Ghez Department of Physics and Astronomy University of CaliforniaLos Angeles 90095-1547USA

This review summarizes a few of the frontiers of Galactic center research that are currently the focus of considerable activity and attention. It is aimed at pro- viding a necessarily incomplete sketch of some of the timely work being done on phenomena taking place in, or originating in, the central few parsecs of the Galaxy, with particular attention to topics related to the Galactic black hole （GBh）. We have chosen to expand on the following exciting topics： 1） the characterization and the im- plications for the variability of emission from the GBh, 2） the strong evidence for a powerful X-ray flare in the Galactic center within the past few hundred years, and the likelihood that the GBh is implicated in that event, 3） the prospects for detecting the ＂shadow＂ of the GBh, 4） an overview of the current state of research on the central S-star cluster, and what has been learned from the stellar orbits within that cluster, and 5） the current hypotheses for the origin of the G2 dust cloud that is projected to make a close passage by the GBh in 2013.

关键词： Galaxy: center -- black hole physics -- X-rays -- infrared radiation --ISM: clouds

The impacts of suspended mariculture on coastal zones in china and the scope for Integrated Multi-Trophic Aquaculture

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Ecosystem health and Sustainability 2017年第6期3卷 32-51页

作者： Reece Wartenberg Limin Feng Jia Jun Wu Yim Ling Mak leo L.chan Trevor c.Telfer Paul K.S.Lamab.c State Key Laboratory in Marine Pollution City University of Hong KongKowloonHong Kong SARChina Research centre for the Oceans and human health Shenzhen Key Laboratory for Sustainable Use of Marine BiodiversityCity University of Hong Kong Shenzhen Research Institute BuildingShenzhenGuangdongChina Department of Biology and chemistry City University of Hong KongKowloonHong Kong SARChina Department of Biomedical Sciences City University of Hong KongKowloonHong Kong SARChina Institute of Aquaculture University of StirlingStirlingUK

Introduction:china is responsible for more than 60%of global aquaculture *** the frontiers of food production have expanded,the cultivation of marine organisms in coastal zones and the open ocean has grown *** dominant mariculture industry in china is suspended mariculture,which uses net cages,ropes,or other structures suspended in the water column to cultivate aquatic *** systematic,quantitative review provides a clear and comprehensive account of research that has investigated the adverse impacts of suspended mariculture in china and reviews research that has applied Integrated Multi-Trophic Aquaculture(IMTA)systems for mitigating *** work builds on 218 peer reviewed papers that have been published in English-language ***:Eighteen impacts were identified,including chemical,ecological,physical,and socioeconomic *** measures for improving suspended mariculture were recommended consisting of government department,farm management,and ecological engineering *** was the most frequently recommended *** capabil-ities of IMTA for bioremediation and increased farm production were the most frequently studied *** other benefits have been explored but remain *** current challenges facing the expansion of commercial IMTA include limited use of new technology,limited skills development,decreasing production of low trophic-level species,biogeographic and temporal barriers,and negative system ***:Despite challenges,implementing commercial IMTA is a promising measure for reducing the impacts of sus pended mariculture because it presents a range of secondary benefits that can improve the overall sustainability of aquaculture in the coastal zone.

关键词： Aquaculture bioremediation china impacts Integrated Multi-Trophic Aquaculture pollution suspended mariculture

A Brief history of Early Sino—American Relations 1784—1844

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解放军外国语学院学报 1993年第4期16卷 94-103页

作者： leo J.Mahoney Westarkcommunity college

On February 23,1993,the General Secretary of the chinese communist Party,JiangZemin,granted an interview in Beijing to *** ＆World Report’s editor,*** to a relation of their conversation in the March 10,1993,issueof china Daily,Secretary Jiang made a number of important statements about china’scurrent policy towards the United *** remarks were obviously based on

关键词：上工工厂山地油灯山口孤儿扣动沙化班规上注

ESTUARINE AND cOASTAL SEDIMENTATION PROBLEMS

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International Journal of Sediment Research 2005年第1期20卷 39-51页

作者： leo c. VAN RIJN Delft hydraulics and University of Utrecht Prof. The Netherlands

This keynote lecture addresses engineering sedimentation problems in estuarine and coastal environments and practical solutions of these problems based on the results of field measurements, laboratory scale models and numerical models. The three most basic design rules are: (1) try to understand the physical system based on available field data; perform new field measurements if the existing field data set is not sufficient (do not reduce on the budget for field measurements); (2) try to estimate the morphological effects of engineering works based on simple methods (rules of thumb, simplified models, analogy models, i.e. comparison with similar cases elsewhere); and (3) use detailed models for fine-tuning and determination of uncertainties (sensitivity study trying to find the most influencial parameters). Engineering works should be designed in such a way that side effects (sand trapping, sand starvation, downdrift erosion) are minimum. Furthermore, engineering works should be designed and constructed or built in harmony rather than in conflict with nature. This ‘building with nature’ approach requires a profound understanding of the sediment transport processes in morphological systems.

关键词： Sedimentation Sediment transport Morphological modelling

Torsional dynamic response of tapered pile considering compaction effect and stress diffusion effect

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Journal of central South University 2020年第12期27卷 3839-3851页

作者： GUAN Wen-jie WU Wen-bing JIANG Guo-sheng chIN Jian leo DENG Guo-dong MOE Engineering Research center of Rock-Soil Drilling&Excavation and Protection Faculty of EngineeringChina University of GeosciencesWuhan 430074China MOE Guangxi Key Laboratory of Disaster Prevention and Engineering Safety College of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China School of Engineering University of Western SydneyLocked Bag 1797PenrithSydneyNSW 2751Australia School of civil Engineering Central South UniversityChangsha 410075China

considering both the compaction effect of pile surrounding soil and the stress diffusion effect of pile end soil,this paper theoretically investigates the torsional vibration characteristics of tapered *** the complex stiffness transfer model to simulate compaction effect and tapered fictitious soil pile model to simulate stress diffusion,the analytical solution for the torsional impedance at tapered pile top is obtained by virtue of Laplace transform technique and impedance transfer *** on the present solution,a parametric study is conducted to investigate the rationality of the present solution and the influence of soil and pile properties on the torsional vibration characteristics of tapered pile embedded in layered *** results show that,both the compaction effect and stress diffusion effect have significant influence on the torsional vibration characteristics of tapered pile,and these two factors should be considered during the dynamic design of pile foundation.

关键词： tapered pile compaction effect stress diffusion effect complex stiffness transfer model tapered fictitious soil pile model