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Thismia tentaculata(Burmanniaceae tribe Thismieae) from Hong kong:first record of the genus and tribe from continental China

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Journal of Systematics and Evolution 2009年第6期47卷 605-607页

作者： George W.C.HO Shek Shing mAR richard m.k.saunders 812 Fu Yuen HouseChuk Yuen South EstateHong KongChina Ying Wa College Hong KongChina Division of Ecology and Biodiversity School of Biological SciencesThe University of Hong Kong

Populations of Thismia tentaculata(Burmanniaceae tribe Thismieae) are described and illustrated from Tai mo Shan in Hong kong,southern *** represents the first report of the genus and tribe from continental China.

关键词： Burmanniaceae Hong kong new record Thismiaceae Thismia tentaculata

Compressively sampling the optical transmission matrix of a multimode fibre

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Light(Science & Applications) 2021年第5期10卷 916-930页

作者： Shuhui Li Charles saunders Daniel J.Lum John murray-Bruce Vivek k Goyal TomášČižmár David B.Phillips School of Physics and Astronomy University of ExeterExeterEX44QLUK Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan430074HubeiChina Department of Electrical and Computer Engineering Boston UniversityBostonMA02215USA Department of Physics and Astronomy University of Rochester500 Wilson BlvdRochesterNY14618USA Department of Computer Science and Engineering University of South FloridaTampaFL33620USA Leibniz Institute of Photonic Technology Albert-Einstein-Straße 907745JenaGermany Institute of Scientific Instruments of CAS Královopolská14761264BrnoCzech Republic

The measurement of the optical transmission matrix(Tm)of an opaque material is an advanced form of space-variant aberration *** imaging,Tm-based methods are emerging in a range of fields,including optical communications,micro-manipulation,and *** many cases,the Tm is very sensitive to perturbations in the configuration of the scattering medium it ***,applications often require an up-to-the-minute characterisation of the fragile Tm,typically entailing hundreds to thousands of probe ***,we explore how these measurement requirements can be relaxed using the framework of compressive sensing,in which the incorporation of prior information enables accurate estimation from fewer measurements than the dimensionality of the Tm we aim to *** of such priors include knowledge of a memory effect linking the input and output fields,an approximate model of the optical system,or a recent but degraded Tm *** demonstrate this concept by reconstructing the full-size Tm of a multimode fibre supporting 754 modes at compression ratios down to∼5%with good *** show that in this case,imaging is still possible using Tms reconstructed at compression ratios down to∼1%(eight probe measurements).This compressive Tm sampling strategy is quite general and may be applied to a variety of other scattering samples,including diffusers,thin layers of tissue,fibre optics of any refractive profile,and reflections from opaque *** approaches offer a route towards the measurement of high-dimensional Tms either quickly or with access to limited numbers of measurements.

关键词： scattering fibre matrix

Defining the effect of sweep tillage tool cutting edge geometry on tillage forces using 3D discrete element modelling

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Information Processing in Agriculture 2015年第2期2卷 130-141页

作者： mustafa Ucgul John m.Fielke Chris saunders Barbara Hardy Institute School of EngineeringUniversity of South AustraliaMawson LakesSA 5095Australia

The energy required for tillage processes accounts for a significant proportion of total energy used in crop *** many tillage processes decreasing the draft and upward vertical forces is often desired for reduced fuel use and improved penetration,*** studies have proved that the discrete element modelling(DEm)can effectively be used to model the soil–tool *** his study,Fielke(1994)[1]examined the effect of the various tool cutting edge geometries,namely;cutting edge height,length of underside rub,angle of underside clearance,on draft and vertical *** this paper the experimental parameters of Fielke(1994)[1]were simulated using 3D discrete element modelling *** the simulations a hysteretic spring contact model integrated with a linear cohesion model that considers the plastic deformation behaviour of the soil hence provides better vertical force prediction was *** parameters were determined by comparing the experimental and simulation results of angle of repose and penetration *** results of the study showed that the simulation results of the soil-various tool cutting edge geometries agreed well with the experimental results of Fielke(1994)[1].The modelling was then used to simulate a further range of cutting edge geometries to better define the effect of sweep tool cutting edge geometry parameters on tillage *** extra simulations were able to show that by using a sharper cutting edge with zero vertical cutting edge height the draft and upward vertical force were further reduced indicating there is benefit from having a really sharp cutting *** extra simulations also confirmed that the interpolated trends for angle of underside clearance as suggested by Fielke(1994)[1]where correct with a linear reduction in draft and upward vertical force for angle of underside clearance between the ranges of-25 and-5°,and between-5 and 0°.The good correlations give confidence to recommend further invest

关键词： DEm Cutting edge geometry

Panorama of boron nitride nanostructures via lamp ablation

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Nano Research 2019年第3期12卷 557-562页

作者： Sehrina Eshon Weike Zhang martin saunders Yujun Zhang Hui Tong Chua Jeffrey m. Gordon Department of Chemical Engineering The University of Western Australia Perth WA 6009 Australia Centre for microscopy Characterisation and Analysis The University of Western Australia Perth WA 6009 Australia School of Environmental Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Department of material Science and Engineering Shandong University Jinan 250061 China Department of Solar Energy and Environmental Physics Blaustein Institutes far Desert Research Bert-Gurion University of the Negev Sede Boqer Campus 8499000 Israel

A diverse range of remarkable boron n itride (BN) nano structures subsumi ng nano-homs, nano-rods, nano-platelets, and clusters of hollow nano spheres (nano-onions, arguably of greatest applied and fun damental in terest) have bee n produced exclusively from crystalline BN precursor powder via lamp ablation. The procedure is safe, devoid of toxic reagents, simple, rapid and scalable—generating some genres of nan oparticles that had previously proved elusive. Product structure and composition were unambiguously assessed by high-resoluti on transmission electron microscopy, energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy.

关键词： Aboron nitride nanostructures nano-onions lamp ablation non-toxic

The role of monocytes in optic nerve injury

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Neural Regeneration Research 2023年第8期18卷 1666-1671页

作者： Xiangxiang Liu Yuan Liu mohamed m.khodeiry richard k.Lee Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijingChina Bascom Palmer Eye Institute Department of OphthalmologyUniversity of Miami Miller School of MedicineMiamiFLUSA

monocytes,including monocyte-derived macrophages and resident microglia,mediate many phases of optic nerve injury *** microglia respond first,followed by infiltrating macrophages which regulate neuronal inflammation,cell proliferation and differentiation,scar formation and tissue remodeling following optic nerve ***,microglia and macrophages have distinct functions which can be either beneficial or detrimental to the optic nerve depending on the spatial context and temporal sequence of their *** divergent effects are attributed to pro-and anti-inflammatory cytokines expressed by monocytes,crosstalk between monocyte and glial cells and even microglia-macrophage *** this review,we describe the dynamics and functions of microglia and macrophages in neuronal inflammation and regeneration following optic nerve injury,and their possible role as therapeutic targets for axonal regeneration.

关键词： fibrotic scar glial scar inflammation macrophage microglia optic nerve injury regeneration

Surgical management of uveitis-glaucoma-hyphema syndrome

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International Journal of Ophthalmology(English edition) 2020年第6期13卷 935-940页

作者： Abdelrahman m.Elhusseiny richard k.Lee William E.Smiddy Department of Ophthalmology Bascom Palmer Eye InstituteUniversity of Miami Miller School of MedicineMiamiFL 33136USA Department of Ophthalmology Kasr Al-AinySchool of MedicineCairo UniversityCairo 12611Egypt

AIm:To report outcomes of patients after intraocular lens(IOL)repositioning or exchange for the version of the uveitisglaucoma-hyphema(UGH)syndrome that does not include closed loop anterior chamber IOL(nUGH).mETHODS:Chart review of patients with nUGH who underwent IOL repositioning or exchange by one surgeon were *** main outcome measures were best corrected visual acuity(BCVA)as a decimal fraction preoperatively and postoperatively after IOL repositioning or *** findings evaluated included the presence of uveitis,hyphema,elevated intraocular pressure(IOP),and other complications such as pigment dispersion or vitreous *** number of anti-inflammatory and glaucoma medications were assessed before and after IOL repositioning or ***:The study included 14 pseudophakic *** median time at the onset of contemporary UGH after cataract extraction and IOL implantation(CE/IOL)was7.5 *** repositioning or exchange was performed at a mean duration of 8.1±4.7 mo(median:4 mo)after onset of *** mean BCVA was improved from 0.45±0.26 preoperatively after onset of UGH syndrome to 0.76±0.22(P=0.016)after IOL repositioning or *** the14 eyes,uveitis,elevated IOP,and hyphema were present preoperatively in 13,13,and 6 eyes,*** and hyphema resolved in all cases after IOL *** mean IOP was reduced from 26.4±4.5 mm Hg preoperatively to 14.7±4.9 postoperatively(P=0.01).The mean number of glaucoma medications used was reduced from 1.7±1.1 medications preoperatively to 0.8±1.08(P=0.04)***:IOL repositioning or exchange is an effective treatment in many cases for medically resistant contemporary UGH syndrome.

关键词： intraocular lens complications secondary glaucoma vitrectomy

Patterns of grassland invasions by trees: insights from demographic and genetic spatial analyses

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Journal of Plant Ecology 2015年第5期8卷 468-479页

作者： martin Dovčiak richard Hrivnák karol Ujházy Dušan Gömöry State University of New York College of Environmental Science and Forestry(SUNY ESF)1 Forestry DriveSyracuseNY 13210USA Institute of Botany Slovak Academy of SciencesDúbravskácesta 9Bratislava 84523Slovakia Technical University in Zvolen Faculty of ForestryT.G.Masaryka 24Zvolen 96053Slovakia

Aims Woody invasions into grasslands have increased globally due to changing land use,climate and introduced woody species,but spatial processes generating and sustaining these invasions are not well *** gain insight into the patterns of spread of tree populations within grasslands,and to propose a full spatial analytical toolbox for studying native and non-native woody spe-cies spread when long-term data are not available,we tested if 50 years of grassland invasion in Western Carpathians by Norway spruce(Picea abies karst.)proceeded by one of the two tradi-tionally competing hypotheses of species spread:(i)by frontier expansion,or(ii)by advanced groups established ahead of the population *** also tested whether the pattern of invasion changed over *** We analyzed the spatial demographic and genetic patterns of a Norway spruce population invading a Western Carpathian grass-land using ripley’s L(t)and genetic kinship coefficients(Fij).We mapped and genotyped spruce trees across the invasion front(from the invasion leading edge to fully colonized grassland near the source population)using three demographic classes(adults,juve-niles and seedlings)to approximate the temporal aspects of the *** studied how the spatial patterns of invasion by indi-vidual demographic classes and their genetic kinship varied among adjacent plots established at different distances from the source population(ranging from 0 to 160 m,in 40-m distance increments).Important Findings Juveniles were positively genetically related to adults on fine scales(m),suggesting that adults within the grassland acted as a seed source and accelerated early ***,adults did not act as nucleation centers for the formation of advanced juvenile ***,geneti-cally unrelated juveniles formed groups independently of *** groups were small and separate at the leading edge but they increased in size and graded into a continuous zone near the source popul

关键词： genetic spatial structure mountain meadows point pattern analysis population structure secondary succession

Understanding Science Through the Computational Lens

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Journal of Computer Science & Technology 2011年第4期26卷 569-577页

作者： richard m.karp Department of Electrical Engineering and Computer Sciences University of California

This article explores the changing nature of the interaction between computer science and the natural and social sciences. After briefly tracing the history of scientific computation, the article presents the concept of computational lens, a metaphor for a new relationship that is emerging between the world of computation and the world of the sciences. Our main thesis is that, in many scientific fields, the processes being studied can be viewed as computational in nature, in the sense that the processes perform dynamic transformations on information represented as digital data. Viewing natural or engineered systems through the lens of their computational requirements or capabilities provides new insights and ways of thinking. A number of examples are discussed in support of this thesis. The examples are from various fields, including quantum computing, statistical physics, the World Wide Web and the Internet, mathematics, and computational molecular biology.

关键词： computational process computer science and other sciences computational lens

Generalization of predator recognition:Velvet geckos display anti-predator behaviours in response to chemicals from non-dangerous elapid snakes

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Current Zoology 2010年第3期56卷 337-342页

作者： Jonathan k. WEBB Weiguo DU David PIkE richard SHINE School of Biological Sciences University of Sydney NSW 2006 Australia Department of Environmental Sciences School of Life Sciences Hangzhou Normal College 310036 Hangzhou Zhejiang China

many prey species detect chemical cues from predators and modify their behaviours in ways that reduce their risk ofpredation. Theory predicts that prey should modify their anti-predator responses according to the degree of threat posed by thepredator. That is, prey should show the strongest responses to chemicals of highly dangerous prey, but should ignore or respondweakly to chemicals from non-dangerous predators. However, if anti-predator behaviours are not costly, and predators are rarelyencountered, prey may exhibit generalised antipredator behaviours to dangerous and non-dangerous predators. In Australia, mostelapid snakes eat lizards, and are therefore potentially dangerous to lizard prey. Recently, we found that the nocturnal velvetgecko Oedura lesueurii responds to chemicals from dangerous and non-dangerous elapid snakes, suggesting that it displays generalisedanti-predator behaviours to chemicals from elapid snakes. To explore the generality of this result, we videotaped the behaviourof velvet geckos in the presence of chemical cues from two small elapid snakes that rarely consume geckos: the nocturnalgolden-crowned snake Cacophis squamulosus and the diurnal marsh snake Hemiaspis signata. We also videotaped geckos in trialsinvolving unscented cards (controls) and cologne-scented cards (pungency controls). In trials involving Cacophis and Hemiaspischemicals, 50% and 63% of geckos spent long time periods (> 3 min) freezing whilst pressed flat against the substrate, *** half the geckos tested exhibited anti-predator behaviours (tail waving, tail vibration, running) in response to Cacophis(67%) or Hemiaspis (63%) chemicals. These behaviours were not observed in control or pungency control trials. Our resultssupport the idea that the velvet gecko displays generalised anti-predator responses to chemical cues from elapid *** responses to predator chemicals may be common in prey species that co-occur with multiple, ecologically similar,

关键词： Predation risk Chemical cues Lizard Elapidae Gekkonidae Olfaction multipredator