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Two decades of variable retention in british Columbia: a review of its implementation and effectiveness for biodiversity conservation

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Ecological Processes 2019年第1期8卷 402-423页

作者： William J.beese john Deal b.Glen Dunsworth Stephen J.Mitchell Timothy J.Philpott Vancouver Island University 900 Fifth StreetNanaimoBC V9R 5S5Canada Western Forest Products 118–1334 Island Hwy.Campbell RiverBC V9W 8C9Canada Glen Dunsworth Ecological Consulting 7857 Shangri-La Rd.LantzvilleBC V0R 2H0Canada University of british Columbia 2424 Main MallVancouverBC V6T 1Z4Canada bC Min.of Forests Lands and Nat.Res.Oper400–640 Borland St.Williams LakeBC V2G 4T1Canada

Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic ***-term retention of mature forest structures at the time of harvesting(variable retention)is intended to produce future forest stands that more closely resemble conditions that develop after natural disturbances,thereby maintaining greater diversity of habitats for a variety of *** includes features such as live and dead trees representing multiple canopy layers,undisturbed understory vegetation and coarse woody *** the past two decades,variable retention has become common on forest lands in the temperate rainforests of coastal british Columbia(bC)and has been applied to a lesser extent in inland forest *** review of studies in bC and in similar forest types in our region indicates that both aggregated and dispersed retention can contribute to biodiversity conservation by providing short-term‘life-boating’habitat for some species and by enhancing the structural characteristics of future *** example,greater abundance of species present in the pre-harvest forest have been documented for vegetation,birds,carabid beetles,gastropods,ectomycorrhizal fungi and soil fauna in retention cutblocks compared to *** are,however,some negative consequences for timber production such as wind damage to retained trees and reduced growth rates of tree regeneration compared to *** authors suggest an adaptive management approach for balancing competing objectives when faced with *** includes monitoring the implementation and effectiveness of various strategies for achieving *** two decades of experience applying variable retention harvesting to industrial-scale management of forest lands in bC suggests that it is possible to balance production of wood with biodiversity conservation.

关键词： Alternative silvicultural systems Clearcutting biological legacies Forest biodiversity Old-growth Variable retention british Columbia

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

Visual Prostheses: Technological and Socioeconomic Challenges

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Engineering 2015年第3期1卷 288-291页

作者： john b.Troy biomedical Engineering Department Northwestern UniversityEvanston

Visual prostheses are now entering the clinical marketplace. Such prostheses were originally targeted for patients suff ering from blindness through retinitis pigmentosa(RP). However, in late July of this year, for the first time a patient was given a retinal implant in order to treat dry agerelated macular degeneration. Retinal implants are suitable solutions for diseases that attack photoreceptors but spare most of the remaining retinal neurons. For eye diseases that result in loss of retinal output, implants that interface with more central structures in the visual system are needed. The standard site for central visual prostheses under development is the visual cortex. This perspective discusses the technical and socioeconomic challenges faced by visual prostheses.

关键词： neuroprostheses vision eye disease restoration of function rehabilitation

VAPOR-LIQUID EQUILIbRIUM IN THE SYSTEM CARbON DIOXIDE/ISO-PENTANE FROM 253 TO 443 K AT PRESSURES UP TO 10 MPa

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Chinese Journal of Chemical Engineering 1992年第2期 157-163页

作者：程华哲 john A. Zollweg William b. Streett beijing Research Institute of Chemical Industry School of Chemical Engineering Cornell University Ithaca NY14853 U.S.A.

Equilibrium pressures and compositions for the binary mixture carbon dioxide-iso-pentane were measured on nine isotherms from 253K to the iso-pentane critical temperature. On each isotherm, the entire pressure range of phase coexistence was covered. The mixture critical line has been located and is shown to be contiuous in Pressure-Temperature-Composition (P-T-X) space between the critical points of the pure components. Comparisons are made between the experimental results obtained by besserer-Robinson and this work with predictions of the Soave-Redlich Kwong, Peng-Robinson, Kubic-Martin, and Adachi-Lu-Sugle cubic equations of state. None was able to correlate the data within our estimated experimental error.

关键词： iso-pentane carbon dioxide phase equilibrium

Specific features of Eu^(3+) and Tb^(3+) magnetooptics in gadolinium-gallium garnet (Gd_3Ga_5O_(12))

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Journal of Rare Earths 2011年第8期29卷 776-782页

作者： Uygun V. Valiev john b. Gruber 付德君 Vasiliy O. Pelenovich Gary W. burdick Mariya E. Malysheva Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio Department of Physics Wuhan University Department of Physics Andrews University

We reported magnetooptical properties of Eu3＋（4f（6）） and Tb3＋（4f（8）） in single crystals of Gd3Ga5O12 （GGG）, Y3Ga5O12 （YGG）, and Eu3＋（4f（6）） in Eu3Ga5O12 （EuGG） for both ions occupying sites of D2 symmetry in the garnet structure. Absorption, luminescence, and magnetic circular polarization of luminescence （MCPL） spectra of Tb3＋ in GGG and YGG and absorption and magnetic circular dichroism （MCD） of Eu3＋ in EuGG were studied. The data were obtained at 85 K and room temperature （RT）. Magnetic susceptibility of Eu3＋ in EuGG was also measured between 85 K and RT. The magnetooptical and magnetic susceptibility data were modeled using the wavefunctions of the crystal-field split energy （Stark） levels of Eu3＋ and Tb3＋ occupying D2 sites in the same garnets. The results reported gave a precise determination of these Stark level assignments and confirmed the symmetry labels （irreducible representations） of the closely-spaced Stark levels （quasi-doublets） found in the 5D1 （Eu3＋） and 5D4 （Tb3＋） multiplets. Ultraviolet （UV） excitation （300 nm） of the 6PJ and 6IJ states of Gd3＋ in the doped GGG crystals led to emission from 5D4 （Tb3＋） and 5D1 and 5D0 （Eu3＋） through radiationless energy transfer to the 4f（n–1）5d band of Tb3＋ and to UV quintet states of Eu3＋. The temperature-dependent emission line shapes and line shifts of the magnetooptical transitions excited by UV radiation suggested a novel way to explore energy transfer mechanisms in this rare-earth doped garnet system.

关键词： magnetic circular polarization of luminescence magnetic circular dichroism absorption quantum qutting energy transfer magnetic susceptibility rare earths

Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations

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Journal of Rare Earths 2013年第9期31卷 837-842页

作者： Uygun V.Valiev john b.Gruber Anvar K.Mukhammadiev Vasiliy O.Pelenovich 付德君 Gary W.burdick Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio School of Physics and Technology Wuhan University Department of Physics Andrews University

Spectra of absorption, luminescence, magnetic circular dichroism （MCD）, and magnetic circular polarization of lumines- cence （MCPL） in Gd3Ga5O12：Eu3＋ and Eu3Ga3O12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole （MD） and electro-dipole （ED） 4f→4f transitions occurring between Stark sublevels of the 7FJ （J=1, 2） and 5D0 multiplets in Eua＋-containing garnet structures. Quantum mechanical ＂mixing＂ had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3＋ ion for Eu3GasOl2 in MCD due to forbidden MD transition 7F1→SD0 and for GdaGasOiE：EU3＋ in MCPL due to MD 4f→4f transition 5Do→7F1 and forced ED-transition 5Do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f（6） ground electronic configuration of Eu3＋ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 meV.

关键词： : magnetic circular dichroism magnetic circular polarization luminescence adsorption garnet non-Kramers ion rare earths

Mathematical Challenges to Macroevolution

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Journal of Applied Mathematics and Physics 2022年第11期10卷 3385-3391页

作者： john b. Andelin Williston North Dakota USA

The theory of evolution was advanced by Darwin in 1859, prior to Mendel’s experiments demonstrating the particulate nature of inheritance. The modern synthesis was formulated in the early 1940s, well before the concept of coded information was understood. This paper outlines four mathematical challenges to the modern synthesis, which are based on current understanding of the proposed mechanisms of evolutionary change within the constraints of experimental molecular biology.

关键词： Evolution Convergence Probability binomial Distribution Formula Ex Post Facto Probability Post-Hoc Probability Modern Synthesis

AN EXTENSION OF THE HARDY-LITTLEWOOD-PóLYA INEQUALITY

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Acta Mathematica Scientia 2011年第6期31卷 2285-2288页

作者： john Villavert Department of Applied Mathematics University of Colorado at Boulder

The Hardy-Littlewood-PSlya （HLP） inequality [1] states that if a ∈ lp, b ∈ 1q and In this article, we prove the HLP inequality in the case where A = 1,p = q = 2 with a logarithm correction, as conjectured by Ding ... 详细信息

关键词： Hardy-Littlewood-Polya inequality logarithm correction

bemisia tabaci Phylogenetic Groups in India and the Relative Transmission Efficacy of Tomato leaf curl bangalore virus by an Indigenous and an Exotic Population

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Journal of Integrative Agriculture 2012年第2期11卷 235-248页

作者： R V Chowda-Reddy M Kirankumar Susan E Seal V Muniyappa Girish b Valand M R Govindappa john Colvin Agriculture Health and Environment GroupNatural Resources InstituteUniversity of Greenwich at MedwayChatham MaritimeKentME4 4TBUnited Kingdom Southern Crop Protection and Food Research Centre London-N5V 4T3Canada Department of Plant Pathology University of Agricultural SciencesBangalore-560 065India Department of Plant Pathology Gujarat Agricultural UniversityAnand 388110GujaratIndia

bemisia tabaci adults from various host-plant species were collected from 31 regions across India.266 *** samples were first screened by RAPD-PCR to examine molecular variability and to select individuals with different ***-plant and region of collection were then used to select 25 individuals for PCR amplification and sequencing of their partial mitochondrial cytochrome oxidase subunit one（mtCOI）*** comparisons with mtCOI consensus sequences showed that the majority of these samples had 〈3.5% sequence divergence from groups currently termed Asia I,Asia II-5,Asia II-7,and Asia *** biotype-b *** from India clustered into the Middle East-Asia Minor 1 group.A new group of *** from Coimbatore,collected from pumpkin,was related most closely to the Asia I group（6.2% sequence divergence from the consensus Asia I sequence）.To increase our understanding of the epidemiology of tomato leaf curl disease（ToLCD）and the key *** genetic groups involved in virus spread,the indigenous Asia I and the exotic biotype-b population from South India were used to carry out transmission experiments using Tomato leaf curl bangalore virus（ToLCbV）.The acquisition access periods（AAP）,inoculation access periods（IAP）,latent periods（LP）,and ToLCbV transmission efficiencies of the two populations were compared and the biotype-b had the more efficient transmission *** results are discussed in relation to recent changes in the epidemiology of tomato leaf curl disease in South India.

关键词： begomoviruses mitochondrial cytochrome oxidase whitefly bemisia tabaci virus-vector relationships epidemiology