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Central role of the LEAFY COTYLEDON1 transcription factor in seed development

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journal of Integrative Plant Biology 2019年第5期61卷 564-580页

作者： Leonardo jo julie M.Pelletier john j.Harada Department of Plant Biology and Plant Biology Graduate Group University of CaliforniaDavis USA

seed development is a complex period of the flowering plant life *** fertilization,the three main regions of the seed,embryo,endosperm and seed coat,undergo a series of developmental processes that result in the production of a mature seed that is developmentally arrested,desiccated,and metabolically *** processes are highly coordinated,both temporally and spatially,to ensure the proper growth and development of the *** transcription factor,LEAFY COTYLEDON1(LEC1),is a central regulator that controls several aspects of embryo and endosperm development,including embryo morphogenesis,photosynthesis,and storage reserve ***,LEC1 regulates distinct sets of genes at different stages of seed *** its critical importance for seed development,an understanding of the mechanisms underlying LECi's multifunctionality is only beginning to be *** studies describe the roles of specific transcription factors and the hormones,gibberellic acid and abscisic acid,in controlling the activity and transcriptional specificity of LEC1 across seed ***,studies indicate that LEC1 acts as a pioneer transcript!on factor to promote epigenetic reprogramming during *** this review,we discuss the mechanisms that enable LEC1 to serve as a central regulator of seed development.

关键词： seed development flowering plant seed development

Ads/QCD and light front holography: A new approximation to QCD

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Chinese Physics C 2010年第9期34卷 1229-1235页

作者： stanley j.Brodsky Guy F.de Téramond sLAC National Accelerator Laboratory Stanford University Universidad de Costa Rica

The combination of Anti-de sitter space （Ads） methods with light-front holography leads to a semi-classical first approximation to the spectrum and wavefunctions of meson and baryon light-quark bound *** from the bound-state Hamiltonian equation of motion in QCD,we derive relativistic lightfront wave equations in terms of an invariant impact variable ζ which measures the separation of the quark and gluonic constituents within the hadron at equal light-front *** equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-j modes in anti–de sitter （Ads） *** eigenvalues give the hadronic spectrum,and its eigenmodes represent the probability distributions of the hadronic constituents at a given *** to the light meson and baryon spectra are *** predicted meson spectrum has a string-theory Regge form M^ 2 = 4κ ^2 （n＋L＋s/2）;i.e.,the square of the eigenmass is linear in both L and n,where n counts the number of nodes of the wavefunction in the radial variable ζ.The space-like pion and nucleon form factors are also well *** thus obtains a remarkable connection between the description of hadronic modes in Ads space and the Hamiltonian formulation of QCD in physical space-time quantized on the light-front at fixed light-front time τ.The model can be systematically improved by using its complete orthonormal solutions to diagonalize the full QCD lightfront Hamiltonian or by applying the Lippmann-schwinger method in order to systematically include the QCD interaction terms.

关键词： gauge/gravity correspondence light-front dynamics strongly coupled QCD meson and baryon spectrum meson and nucleon form factors

Variable retention harvesting: conceptual analysis according to different environmental ethics and forest valuation

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Ecological Processes 2019年第1期8卷 485-491页

作者： Leonardo Galetto Carolina Torres Guillermo j.Martínez Pastur Departamento de Diversidad Biológica y Ecología FCEFyNUniversidad Nacional de Córdoba(UNC)Vélez Sarsfield 16115000 CórdobaArgentina Instituto Multidisciplinario de Biología Vegetal(IMBIV) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Vélez Sarsfield 16115000 CórdobaArgentina Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina.

Background:Conceptual clarity is important to attain precise communication of scientific knowledge and to implement appropriate technological and policy *** concepts referring to forest management are widely used by decision-makers,regardless of their *** the scientific and methodological issues of forestry practices are frequently discussed in the literature,their normative dimensions are rarely ***,linguistic uncertainty increases when different environmentally ethical perspectives and ways of valuing forests are *** objective was to compare different conceptualizations on the silvicultural systems suggested for forest management and the implications they have for *** have conceptually contrasted highintensity forestry practices with variable retention harvesting,considering different environmentally ethical perspectives and forest valuation ***:Clear boundaries between clear-cutting,selective logging,and variable retention harvesting can be evidenced when different ethical points of view and alternatives in the human-nature relationships are *** have found a variety of definitions of variable retention harvesting that can be analyzed under different ethical *** contrasting views on variable retention harvesting can be evidenced if nature is considered to be purely at human’s service or if it is conceptualized as humans co-inhabiting with *** latter position implies that the maintenance of ecological,evolutionary,and historical processes supported by unmanaged forest stands is a crucial step for forest management proposals based on variable retention ***:Forestry practices that are focused on forest yields and that misinterpret functional uncertainty of forest functioning would be ***,forestry with variable retention harvesting could imply good yields with reasonable conservation management in some contexts,while it could be unacce

关键词： Environmental ethical perspectives Consequentialism Deontological ethics Virtue ethics Policy options for forest and biocultural conservation

Transparency of Cosmic Radio Waves Caused by seismic and Volcano Activities

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journal of Electromagnetic Analysis and Applications 2014年第11期6卷 335-341页

作者： s. Koshevaya Yu. Kotsarenko j. A. Escobedo A. Kotsarenko V. Yutsis CIICAp Autonomous University of State Morelos (UAEM) Cuernavaca Mexico Universidad Autónoma del Carmen Facultad de Ingeniería Ciudad del Carmen Mexico san Luis Potosi Institute of scientific Research and Technology Applied Geoscience Department San Luis Potosi Mexico

The generation of different waves in the atmosphere and ionosphere caused by seismic and volcano activities has changed the transparency for cosmic radio waves. It is possible to analyze two cases: the first case caused by the atmospheric acoustic wave, which creates a periodic structure of the electron density in the ionosphere. It is shown that the resonant passing of the radio waves takes place, when the length of the acoustic wave is equal to one or a few lengths of the radio wave. The second case produces the electron density decrease in the F-layer of the ionosphere resulting in an increase in the transparency of the ionosphere for cosmic radio waves. The review of these phenomena is provided in this work and both cases have been confirmed experimentally.

关键词： Transparency Plasma Radio Waves

Finite Element Modeling Of Low Heat Conducting Building Bricks

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journal of Minerals and Materials Characterization and Engineering 2012年第8期11卷 800-806页

作者： O. O. Oluwole j. s. joshua H. O. Nwagwo Department Of Mechanical Engineering University Of Ibadan Nigeria

Heat conduction through conventional and interlocking building bricks with cavities was studied in this work. Heat transfer analysis was carried out using MATLAB? partial differential equation toolbox. Regular and staggered hole arrangements were studied. Results showed that four staggered holed interlocking bricks were effective in thermal resistance into the bricks and increasing the holes beyond four did not give any thermal resistance advantage. For the conventional bricks staggered holes did not give any thermal resistance advantage but the four-holed bricks were also adjudged to be effective in thermal resistance into the brick surface. Increasing the number of holes beyond four in conventional bricks did give some thermal resistivity advantage but very minimal. structural strengths of holed bricks were not considered in this study.

关键词： Building Bricks Finite Element Modeling Heat Conduction

Knowledge, attitude and practice related to liver fluke infection in northeast Thailand

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World journal of Gastroenterology 2007年第12期13卷 1837-1840页

作者： Natthawut Kaewpitoon soraya j Kaewpitoon Prasit Pengsaa Chutigan Pilasri College of Medicine and Public Health Ubon Rajathanee University Ubon Ratchathani 34190 ThailandSoraya J Kaewpitoon Primary Care Unit Ubon Rajathanee University Ubon Ratchathani 34190 Thailand Primary Care Unit Ubon RajathaneeUniversity Ubon Ratchathani 34190 Thailand

AIM： To investigate the knowledge, attitude and practice （KAP） in prevention and control of liver fluke infection in northeast Thailand. METHODs： A descriptive KAP survey pertaining to liver fluke infection was carried out in june 2005 to October 2006 using structured questionnaires. Data were collected by questionnaires consisting of general parameters, knowledge, attitude, practice, and a history of participation in the prevention and control of liver fluke infection. REsULTs： A total of 1077 persons who were interviewed and completed the questionnaires were enrolled in the study. The majority were females （69.5%） and many of them were 15-20 years of age （37.26%）. The questionnaires revealed that information resources on liver fluke infection included local public health volunteers （31.37%）, public health officers （18.72%）, televisions （14.38%）, local heads of sub-districts （12.31%）, doctors and nurses （9.18%）, newspaper （5.72）, intemets （5.37%）, and others （12.95%）. Fiftyfive point eleven percent of the population had a good level of liver fluke knowledge concerning the mode of disease transmission and 79.72% of the population had a good level of prevention and control knowledge with regards to defecation and consumption. The attitude and practice in liver fluke prevention and control were also at a good level with a positive awareness, participation, and satisfaction of 72.1% and 60.83% of the persons studied. However, good health behavior was found in 39.26% and 41.42% of the persons studied who had unhygienic defecation and ate raw cyprinoid＇s fish. The result also showed that 41.25% of the persons studied previously joined prevention and control campaigns. CONCLUsION： The persons studied have a high level of liver fluke knowledge and positive attitude. However, improvement is required regarding personal hygiene specifically with hygienic defecation and consumption of undercooked fish.

关键词： Knowledge Attitude Practice Liver fluke Northeast Thailand

An approach to viscoelastic c haracterization of dispersive media by inversion of a general wave propagation model

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journal of Innovative Optical Health sciences 2017年第6期10卷 73-88页

作者： Fernando Zvietcovich jannick P.Rolland Kevin j.Parker Department of Electrical and Computer Engineering University of Rochester Rochester New York 14627USA The Institute of Optics University of Rochester Rochester New York 14627USA

In the characterization of elastic properties of tissue using dynarmic optical coherence elasto-graphy,shear/surface waves are propagated and tracked in order to estimate speed and Y oung's ***,for dispersive tssues,the displacement pulse is highly damped and distorted during propagation,diminishing the ffectiveness of peak tracking approaches,and leading to biased cstimates of wave ***,plane wave propagation is sometimes assumed,which contributes to estimation ***,we invert a wave propagation model that incorpo-rates propagation,decay,and distortion of pulses in a dispersive media in order to accurately estimate its elastic and viscous *** model uses a general first-order approximation of dispersion,avoiding the use of any particular rheological model of *** are conducted in elastic and viscoelastic tissue mimicking phantoms by producing a Gaussian push using acoustic radiation force excitation and measuring the wave propagation using a Fourier domain optical coherence tomography *** confirmed the ffectiveness of the inversion method in est imat ing viscoelastic parameters in both the viscoelastic and elastic phantoms when compared to mechanical ***,the viscoelastic characterization of a fresh porcine comea was *** results validate this approach when compared to other methods.

关键词： Elastography viscoelasticity cylindrical waves optical coherence tomography shear waves surface acoustic waves viscoelastic pha ntoms

Parallel loop recovery with quiescent compensation for high performance feedback control of systems with imperfect actuators

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Control Theory and Technology 2019年第3期17卷 201-215页

作者： Y.V.O'BRIEN j.F.O'BRIEN Department of Electrical and Computer Engineering University of Wyoming Laramie WY 82073 U.S.A.

Actuator limits and imperfections introduce multiple nonlinearities in a feedback *** standard mild-feedback systems (e.g.,PID) are intrinsically robust to such nonlinearities,the stability of large feedback systems is *** eliminates from consideration the usage of imperfect actuators in large feedback applications and available disturbance rejection as a result is not *** implementation of multiple-path nonlinear dynamic compensation (NDC),however,allows the combination of large feedback and imperfect actuation and is the focus of this *** nonlinearities due to actuator imperfection are often difficult to model,the stability of the NDC systems is assessed using multivariable absolute stability *** features of a parallel loop recovery system with loop transmission modulus reduction compensation in the quiescent condition are compared to an alternative approach of strict modulus reduction via nonlinear compensation for stability *** of the loop recovery approach is illustrated using experimental data from a voice-coil actuated disturbance rejection system.

关键词： Feedback control imperfect actuators nonlinear dynamic compensation

Planting position and shade enhance native seedling performance in forest restoration for an endangered malagasy plant

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Plant Diversity 2019年第2期41卷 118-123页

作者： Cyprien Miandrimanana j.Leighton Reid Tahiry Rivoharison Chris Birkinshaw Missouri Botanical Garden Madagascar Research and Conservation Program Center for Conservation and sustainable Development Missouri Botanical Garden

The critically endangered tree schizolaena tampoketsana is confined to a few diminished and degraded forest fragments on the Malagasy highlands. This habitat is vulnerable to loss due to frequent fires in the surrounding grassland that threaten to spread into the forest. One of these fragments is the focus a conservation project and here the managers aim to conserve s. tampoketsana by restoring its forest habitat to its former extent as evidenced by remnant woody plants. To inform this activity the survival and early-stage growth of seedlings of four locally native tree species were compared under contrasting conditions of proximity to the remaining forest and shade. After 12 months, seedlings of three species(Baronia taratana, Eugenia pluricymosa, Uapaca densifolia) survived better and experienced improved growth in height in grassland close to the existing forest rather than distant from it, and two survived better with shade rather than unshaded. A number of mechanisms could explain these results including reduced exposure to desiccating sunlight and winds and better soil and greater water availability close to the forest. The seedlings of one species(Nuxia capitata) survived well under all conditions. This study suggests that reforestation in these dry highlands is most feasible adjacent to remnant forest fragments and in microhabitats that minimize water loss, though young plants of some tree species may be capable of surviving in harsher conditions.

关键词： Grassland Fire Forest restoration Local environment schizolaena tampoketsana