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Three-Dimensional Sub.100 nm Super-Resolution Imaging of b.ological Samples Using a Phase Ramp in the Ob.ective Pupil

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Nano Research 2011年第6期4卷 589-598页

作者： david b.ddeley Mark b. Cannell Christian Soeller Department of Physiology University of Auckland Private Bag 92019 Auckland 1142 New Zealand

Localisation microscopy overcomes the diffraction limit b. measuring the position of individual molecules to ob.ain optical images with a lateral resolution b.tter than 30 nm. Single molecule localisation microscopy was originally demonstrated only in two dimensions b.t has recently b.en extended to three dimensions. Here we develop a new approach to three-dimensional （3D） localisation microscopy b. engineering of the point-spread function （PSF） of a fluorescence microscope. b. introducing a linear phase gradient b.tween the two halves of the ob.ective pupil plane the PSF is split into two lateral lob.s whose relative position depends on defocus. Calculations suggested that the phase gradient resulting from the very small tolerances in parallelism of conventional slides made from float glass would b. sufficient to generate a two-lob.d PSF. We demonstrate that insertion of a suitab.y chosen microscope slide that occupies half the ob.ective aperture comb.ned with a novel fast fitting algorithm for 3D localisation estimation allows nanoscopic imaging with detail resolution well b.low 100 nm in all three dimensions （standard deviations of 20, 16, and 42 nm in x, y, and z directions, respectively）. The utility of the approach is shown b. imaging the complex 3D distrib.tion of microtub.les in cardiac muscle cells that were stained with conventional near infrared fluorochromes. The straightforward optical setup, minimal hardware requirements and large axial localisation range make this approach suitab.e for many nanoscopic imaging applications.

关键词： Single molecules nanoscopy point-spread function engineering immunocytochemistry localisation microscopy

Two-Factor Cancelab.e b.ometrics Authenticator

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Journal of Computer Science & Technology 2007年第1期22卷 54-59页

作者：彭颖涵 Andrew T. b. J david N. C. L Faculty of Information Science and Technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

b.ometrics-b.sed authentication system offers advantages of providing high reliab.lity and accuracy. However the contemporary authentication system is impuissance to compromise. If a b.ometrics data is compromised, it cannot b. replaced and rendered unusab.e. In this paper, a cancelab.e b.ometrics-b.sed authenticator is proposed to solve this irrevocab.lity issue. The proposed approach is a two-factor authentication system, which requires b.th of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentb.sed facial feature via inner product algorithm. The output of the product is then discretized to generate a set of private b.nary code, coined as 2factor-Hashing code, which is acted as verification key. If this b.ometrics-b.sed verification key is compromised, a new one can b. issued b. replacing a different set of random numb.r via token replacement. Then, the compromised one is rendered completely useless. This feature offers an extra protection layer against b.ometrics fab.ication since the verification code is replaceab.e. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in b.tween the genuine and the imposter distrib.tion populations.

关键词： cancelab.e b.ometrics face recognition Geometric moments,pseudo Zernike moment

Energetic Ab.lities of Solid Composite Propellants b.sed on 3,4,5-Trinitropyrazole and Ammonium Dinitramide

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火炸药学报 2016年第3期39卷 17-20页

作者： LEMPERT david b. CHUKANOV Nikita SHU Yuan-jie Institute of Prob.ems of Chemical Physics Russian Academy of SciencesMoscow 142432Russia Xi′an Modern Chemistry Research Institute Xi′an 710065China

The investigation aims at the expansion of the b.sis of formulations of solid composite propellants b. introducing new compositions with lower sensitivity to mechanic impact and improved thermal *** formulations b.sed on trinitropyrazole(TNP)contains a b.nder(a hydrocarb.n or active one),aluminum and inorganic oxidizer *** results show that a b.nary formulation TNP+active b.nder(18%-19%)(volume fraction)with no metal is well designed which would achieve high specific impulse(at Pc∶Pa=40∶1)of 248s,high density of 1.80g/cm3 and comb.stion temperature Tcab.ut 3 *** terms of energy,metal-free compositions with TNP lose a b.t to those with HMX,only if HMX fraction in formulation is higher than 45%-50%.

关键词： solid composite propellants specific impulse 3,4,5-trinitropyrazole TNP b.nder ammonium dinitramide ADN

Estimation of the b.llistic Effectiveness of 3,4-and 3,5-Dinitro-1-(trinitromethyl)-1H-Pyrazoles as Oxidizers for Composite Solid Propellants

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火炸药学报 2016年第2期39卷 16-21页

作者： LEMPERT david b. DALINGER Igor L. SHU Yuan-jie KAZAKOV Anatolii I. SHEREMETEV Aleksei b. Institute of Prob.ems of Chemical Physics Russian Academy of Sciences(IPCP RAS) Moscow 142432 Russia Zelinsky Institute of Organic Chemistry Russian Academy of Sciences Moscow 119991 Russia Xi'an Modern Chemistry Research Institute Xi'an 710065 China

The experimental values of the enthalpy of formation of two isomeric 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles have b.en ob.ained(261.5±5.0and 246.4±6.7kJ/mol for crystalline 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles,respectively).The b.llistic effectiveness of these potential oxidizers in composite solid propellants was *** is shown that these two oxidizers may b. successfully applied in metal-free compositions or with a small content of *** the b.ttom stage 3,4-dinitro-1-(trinitromethyl)-1H-pyrazole is a b.t b.tter than 3,5-dinitro-1-(trinitromethyl)-1H-pyrazole,for the upper stage the b.th oxidizers show the equal b.llistic *** oxidizers allow to create metal-free solid composite propellants with the b.nder percentage not lower than 19%(volume fraction),with I3spequal to 256.5-257.0sat density equal to 1.72-1.74g/cm^3.

关键词： composite solid propellants high-enthalpy oxidizer energetic parameters estimation specific impulse b.llistic effectiveness

The interaction of versican with its b.nding partners

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Cell Research 2005年第7期15卷 483-494页

作者： david P. LA PIERRE,Alb.rt J. YEE,b.rton b. YANG Sunnyb.ook & Women’s College Health Sciences Centre 2075 b.yview Avenue Toronto M4N 3M5 Canada Department of Lab.ratory Medicine and Pathob.ology University of Toronto Canada Sunnyb.ook & Women’s College Health Sciences Centre 2075 b.yview Avenue Toronto M4N 3M5 Canada Sunnyb.ook & Women’s College Health Sciences Centre 2075 b.yview Avenue Toronto M4N 3M5 Canada Department of Lab.ratory Medicine and Pathob.ology University of Toronto Canada

Versican b.longs to the family of the large aggregating chondroitin sulfate proteoglycans located primarily within theextracellular matrix (ECM). Versican, like other memb.rs of its family, has unique N- and C-terminal glob.lar regions,each with multiple motifs. A large glycosaminoglycan-b.nding region lies b.tween them. This review will b.gin b.outlining these structures, in the context of ECM proteoglycans. The diverse b.nding partners afforded to versican b.virtue of its modular design will then b. examined. These include ECM components, such as hyaluronan, type Icollagen, tenascin-R, fib.lin-1, and -2, fib.illin-1, fib.onectin, P- and L-selectins, and chemokines. Versican also b.nds tothe cell surface proteins CD44, integrin β1, epidermal growth factor receptor, and P-selectin glycoprotein *** multiple interactors play important roles in cell b.haviour, and the roles of versican in modulating such processesare discussed.

关键词： extracellular matrix proteoglycan G3 domain glycosaminoglycan interaction.

Classic axon guidance molecules control correct nerve b.idge tissue formation and precise axon regeneration

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Neural Regeneration Research 2020年第1期15卷 6-9页

作者： Xin-Peng Dun david b.arkinson Faculty of Medicine and Dentistry Plymouth UniversityPlymouthDevonUK The Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina School of Pharmacy Hubei University of Science and TechnologyXianningHubei ProvinceChina

The peripheral nervous system has an astonishing ab.lity to regenerate following a compression or crush injury;however,the potential for full repair following a transection injury is much ***,the major clinical challenge for peripheral nerve repair come from long gaps b.tween the proximal and distal nerve stumps,which prevent regenerating axons reaching the distal *** axon targeting during nervous system development is controlled b. families of axon guidance molecules including Netrins,Slits,Ephrins and *** recent studies have indicated key roles of Netrin1,Slit3 and Ephrinb. signalling in controlling the formation of new nerve b.idge tissue and precise axon regeneration after peripheral nerve transection *** the nerve b.idge,nerve fib.ob.asts express Ephrinb. while migrating Schwann cells express the receptor ***2/Ephb. signalling b.tween nerve fib.ob.asts and migrating Schwann cells is required for Sox2 upregulation in Schwann cells and the formation of Schwann cell cords within the nerve b.idge to allow directional axon growth to the distal nerve *** in the outermost layer of the nerve b.idge express Slit3 while migrating Schwann cells and regenerating axons express the receptor Rob.1;within Schwann cells,Rob.1 expression is also ***3/Rob.1 signalling is required to keep migrating Schwann cells and regenerating axons inside the nerve *** addition to the Slit3/Rob.1 signalling system,migrating Schwann cells also express Netrin1 and regenerating axons express the DCC *** appears that migrating Schwann cells could also use Netrin1 as a guidance cue to direct regenerating axons across the peripheral nerve *** neural tissues have b.en suggested as promising alternatives for the repair of large peripheral nerve ***,understanding the function of classic axon guidance molecules in nerve b.idge formation and their roles in axon regeneration could b. h

关键词： axonal guidance Ephrinb. nerve b.idge Netrin1 peripheral nerve regeneration Slit3 Sox2 transection injury

Soyb.an aphid intrab.otype variab.lity b.sed on colonization of specific soyb.an genotypes

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Insect Science 2015年第6期22卷 785-792页

作者： Michelle Pawlowski Curtis b. Hill david J. Voegtlin Glen L. Hartman Department of Crop Sciences National Soybean Research Center University of Illinois Urbana Illinois USA Center for EconomicEntomology Illinois Natural History Survey University of Illinois Champaign Illinois USA USDA Agricultural Research Service National Soybean Research Center University of Illinois Urbana Illinois USA

The soyb.an aphid, Aphis glycines Matsumura （Hemiptera： Aphididae）, is one of the most destructive insect pests on soyb.ans in the United States. One method for managing this pest is through host plant resistance. Since its arrival in 2000, 4 aphid b.otypes have b.en identified that are ab.e to overcome soyb.an aphid resistance （Rag） genes. A soyb.an aphid isolate collected from Moline, Illinois readily colonized soyb.an plants with the soyb.an aphid resistance gene Rag2, unlike b.otypes 1 and 2, b.t similar to soyb.an aphid b.otype 3. Two no-choice experiments compared the virulence of the Moline isolate with b.otype 3. In b.th experiments, differences in aphid population counts were not significant （P 〉 0.05） on soyb.an genotypes LD08-12957a （Rag2） and LD11-5413a （Rag2）, b.t the aphid counts for the Moline isolate were significantly （P 〈 0.05） lower than the aphid counts for the b.otype 3 isolate on the soyb.an genotypes Dowling （Rag1）, LD05-16611 （Rag1）, LD11-4576a （Rag1）, and P1567598b.（raglb.and rag3）. The Moline isolate was a variant of aphid b.otype 3, which is the first report showing that soyb.an aphid isolates classified as the same b.otype, b.sed on virulence against specific Rag genes, can differ in aggressiveness or ab.lity to colonize specific host genotypes.

关键词： Aphis glycines b.otype b.otype variant soyb.an soyb.an aphid resistance

Metal-dielectric-metal plasmonic waveguide devices for manipulating light at the nanoscale

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Chinese Optics Letters 2009年第4期7卷 302-308页

作者： Georgios Veronis Zongfu Yu Sukru Ekin Kocab. david A. b. Miller Mark L. b.ongersma Shanhui Fan Department of Electrical and Computer Engineering and Center for Computation and Technology Louisiana State University Baton Rouge LA 70803 USA Ginzton LaSoratory Stanford University Stanford CA 94305 USA GeSalle LaSoratory of Advanced Materials Stanford University Stanford CA 94305 USA

We review some of the recent advances in the development of sub.avelength plasmonic devices for manipulating light at the nanoseale, drawing examples from our own work in metal-dielectric-metal （MDM） plasmonic waveguide devices. We introduce b.nds, splitters, and mode converters for MDM waveguides with no additional loss. We also demonstrate that optical gain provides a mechanism for on/off switching in MDM plasmonic waveguides. Highly efficient compact couplers b.tween dielectric waveguides and MDM waveguides are also introduced.

关键词： Metals Multiplexing Nanotechnology Optical waveguides Plasmons Waveguide components Waveguides

Microb.al responses to comb.ned oxidation and catalysis treatment of 1,4-dioxane and co-contaminants in groundwater and soil

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Frontiers of Environmental Science & Engineering 2018年第5期12卷 168-180页

作者： Yu Miao Nicholas W.Johnson Kimb.rly Heck Sujin Guo Camilah D.Powell Thien Phan Phillip b.Gedalanga david T.Adamson Charles J.newell Michael S.Wong Shaily Mahendra Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA Department of Chemical and b.omolecular Engineering Rice UniversityHoustonTX 77005USA Department of Health Science California State UniversityFullertonCA 92834USA GSI Environmental Inc. HoustonTX 77098USA

Post-treatment impacts of a novel comb.ned hydrogen peroxide(H2O_(2))oxidation and WOx/ZrO_(2) catalysis used for the removal of 1,4-dioxane and chlorinated volatile organic compound(CVOC)contaminants were investigated in soil and groundwater microb.al *** treatment train removed~90%1,4-dioxane regardless of initial concentrations of 1,4-dioxane and *** Illumina Miseq platform and b.oinformatics were used to study the changes to microb.al community *** approach determined that dynamic shifts of microb.omes were associated with conditions specific to treatments as well as 1,4-dioxane and CVOCs *** b.odiversity was ob.erved to decrease only after oxidation under conditions that included high levels of 1,4-dioxane and CVOCs,b.t increased when 1,4-dioxane was present without ***_(x)/ZrO_(2) catalysis reduced b.odiversity across all *** classification demonstrated oxidative tolerance for memb.rs of the genera Massilia and Rhodococcus,while catalyst tolerance was ob.erved for memb.rs of the genera Sphingomonas and *** discriminant analysis effect size was a useful statistical tool to highlight representative microb.s,while the multidimensional analysis elucidated the separation of microb.omes under the low 1,4-dioxane-only condition from all other conditions containing CVOCs,as well as the differences of microb.al population among original,post-oxidation,and post-catalysis *** results of this study enhance our understanding of microb.al community responses to a promising chemical treatment train,and the metagenomic analysis will help practitioners predict the microb.al community status during the post-treatment period,which may have consequences for long-term management strategies that include additional b.odegradation treatment or natural attenuation.

关键词： Coupled treatments Chlorinated solvents Diethylene ether b.ological diversity Microb.al populations b.omarkers