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Systems Biology Approach Pinpoints minimum Requirements for Auxin Distribution during Fruit Opening

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molecular Plant 2019年第6期12卷 863-878页

作者： Xin-Ran Li Renske m.A.Vroomans Samantha fox Veronica A.grieneisen Lars Φstergaard Athanasius F.m.maree Crop genetics John Innes Centre Norwich NR4 7UH UK Computational and Systems Biology John Innes Centre Norwich NR4 7UH UK Centre of Excellence in Computational and Experimental Developmental Biology Institute of Biotechnology University of Helsinki 00014 Helsinki Finland Cell and Developmental Biology John Innes Centre Norwich NR4 7UH UK School of Biosciences Cardiff University Cardiff CF10 3AX Wales UK

The phytohormone auxin is implied in steering various developmental decisions during plant morphogenesis in a concentration-dependent *** maxima have been shown to maintain meristematic activity,for example,of the root apical meristem,and position new sites of outgrowth,such as during lateral root initiation and *** recently,it has been demonstrated that sites of auxin minima also provide positional *** the developingArabidopsis fruit,auxin minima are required for correct differentiation of the valve *** remains unclear,however,how this auxin minimum is generated and ***,we employ a systems biology approach to model auxin transport based on experimental *** allows us to determine the minimal requirements for its *** simulations reveal that two alternative processes-which we coin "flux-barrier" and "flux-passage"-are both able to generate an auxin minimum,but under different parameter *** models are in principle able to yield similar auxin profiles but present qualitatively distinct patterns of auxin *** models were tested by tissue-specific inducible ablation,revealing that the auxin minimum in the fruit is most likely generated by a flux-passage *** predictions were further supported through 3D PIN localization imaging and implementing experimentally observed transporter *** such an experimental-modeling cycle,we predict how the auxin minimum gradually matures during fruit development to ensure timely fruit opening and seed dispersal.

关键词： auxin mathematical modeling polar auxin transport fruit development systems biology of patterning

micromorphology of Surface Crusts in the Knersvlakte,South Africa

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Journal of mountain Science 2009年第2期6卷 189-196页

作者： Sarah-Jane C.fox Anthony J.mills Rosa m.Poch Department of Soil Science Stellenbosch UniversityStellenbosch South Africa Department of Environment and Soil Science University of LleidaRovira Roure 191 Lleida

Soils in the Knersvlakte are particularly prone to crusting and have lower inherent infiltrability than other soils across western southern Africa. micromorphological techniques were used to examine the structure and porosity of soil crusts in the Knersvlakte to ascertain why crusting is so intense in this region. Quantile regression using boundary lines was employed to examine the relationships between infiltrability and soil properties for all samples （n = 67）. This analysis showed that infiltrability is potentially maximal at low water- dispersible ＇clay plus silt＇ content and low silt content （r^2 = 0.72 and 0.64; respectively, n = 67）（Figure 2）. The strength of crusts, pH, EC, clay mineralogy, and water-dispersible clay, silt and ＇clay plus silt＇ content were compared, and a pore analysis using optical microscopy was undertaken on images of six soil thin sections （n = 6）（circular and parallel polarizers）. Pore analysis was further undertaken on five horizontal slices of equal dimensions taken through each soil thin section. The porosity samples with low infiltrability （〈 100 mm·hr^-1, n = 4） had greater crust strength, lower porosity （both total and in the least porous slice） and greater water-dispersible ＇day plus silt＇ and silt content than the porosity samples with high infiltrability （〉 100mm·hr^-1, n = 2）. The porosity samples with low infiltrability showed a trend of lower pH and greater water dispersible clay percentage. Porosity varied within the porosity samples due to the presence of dense clay/silt bands （〈 0.5 mm in width） with relatively few air vesicles. The porosity samples with horizontal slices of low porosity （but large numbers of air vesicles） had low infiltrability, while those without slices of low porosity （and relatively few air vesicles） had high infiltrability. We conclude that the intense crusting and resultant low infiltrability of soils in the Knersvlakte appears to be related to the formation of thin, dense clay/silt bands in the

关键词： Infiltrability optical microscopy porosity air vesicles

Divergent male and female mate preferences do not explain incipient speciation between lizard lineages

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Current Zoology 2020年第5期66卷 485-492页

作者： Claire A.mcLean Richard A.Bartle Caroline m.Dong Katrina J.Rankin Devi Stuart-fox School of BioSciences The University of MelbourneParkville VIC 3010Australia Sciences Department Museums VictoriaCarlton VIC 3053Australia

Diversification in sexual signals is often taken as evidenee for the importance of sexual selection in speciatio ***,in order for sexual selection to gen erate reproductive isolati on between populations,both signals and mate preferences must diverge ***,assortative mating may result from multiple behavioral mecha nisms,in eluding female mate pref ere nces,male mate preferences,and male-male competition;yet their relative contributions are rarely ***,we explored the role of mate pref ere nces and male competitive ability as pote ntial barriers to gene flow between 2 diverge nt lineages of the taw ny dragon lizard,Ctenophorus decresii,which differ in male throat *** found stronger behavioral barriers to pairings between southern lineage males and northern lineage females than between northern males and southern females,indicating incomplete and asymmetric behavioral isolating *** results were driven by both male and female mate preferences rather than lineage differences in male competitive *** trasexual selecti on is therefore un likely to drive the outcome of sec on dary contact in ***,despite its widely ack no wledged importa nee in *** results are consiste nt with the emergi ng view that although both male and female mate pref ere nces can diverge alongside sexual signals,speciation is rarely driven by divergent sexual selection alone.

关键词： Ctenophorus decresii hybridization male-male competition secondary contact sexual selection

A Quadrature-Based Kinetic model for Dilute Non-Isothermal granular Flows

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Communications in Computational Physics 2011年第6期10卷 216-252页

作者： Alberto Passalacqua Janine E.galvin Prakash Vedula Christine m.Hrenya Rodney O.fox Department of Chemical and Biological Engineering Iowa State UniversityAmesIA 50011-2230USA United States Department of Energy National Energy Technology Laboratory MorgantownWV 26507-0880USA School of Aerospace and mechanical Engineering University of OklahomaNormanOK 73019-0601USA Department of Chemical and Biological Engineering University of ColoradoBoulderCO 80309-0424USA.

A moment method with closures based on gaussian quadrature formulas is proposed to solve the Boltzmann kinetic equation with a hard-sphere collision kernel for mono-dispersed *** orders of accuracy in terms of the moments of the velocity distribution function are considered,accounting for moments up to seventh ***-based closures for four different models for inelastic collisionthe Bhatnagar-gross-Krook,ES-BgK,the maxwell model for hard-sphere collisions,and the full Boltzmann hard-sphere collision integral-are derived and *** approach is validated studying a dilute non-isothermal granular flow of inelastic particles between two stationary maxwellian *** obtained from the kinetic models are compared with the predictions of molecular dynamics(mD)simulations of a nearly equivalent system with finite-size *** influence of the number of quadrature nodes used to approximate the velocity distribution function on the accuracy of the predictions is *** for constitutive quantities such as the stress tensor and the heat flux are provided,and show the capability of the quadrature-based approach to predict them in agreement with the mD simulations under dilute conditions.

关键词： Kinetic equation quadrature-based moment method granular gas collision integral BgK-type model

Photometric light curve solutions of three ultra-short period eclipsing binaries

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Research in Astronomy and Astrophysics 2020年第4期20卷 163-170页

作者： Francesco Acerbi Raul michel Carlo Barani massimiliano martignoni Lexter fox-machado Stazione Astronomica Betelgeuse Magnago 20020Italy Instituto de Astronomia Universidad Nacional Autonoma de MexicoApartado Postal 877C.P.22800 EnsenadaB.C.Mexico

We present the results of our study of the eclipsing binary systems CSS J112237.1+395219,LINEAR 1286561 and LINEAR 2602707 based on new CCD B,V,Rcand Iccomplete light *** ultra-short period nature of these stars,as reported by Drake et al.,is confirmed and the system’s periods are *** light curves were modeled using the 2003 version of the Wilson-Devinney *** necessary,cool spots on the surface of the primary component were introduced to account for asymmetries in the light *** a result,we found that CSS J112237.1+395219 is a W Uma type contact binary system belonging to W subclass with a mass ratio of q=1.61 and a shallow degree of contact of 14.8%where the primary component is hotter than the secondary one by 500 *** 1286561 and LINEAR2602707 are detached binary systems with mass ratios q=3.467 and q=0.987 *** detached systems are low-mass m-type eclipsing binaries with similar *** marginal contact,fill-out factor and temperature difference between components of CSS J112237.1+395219 suggest that this system may be at a key evolutionary state predicted by thermal relaxation oscillation(TRO)*** the estimated absolute parameters,we conclude that our systems share common properties with other ultrashort period binaries.

关键词： techniques:photometric stars:variables:Contact Binary stars:individual:CSS J112237.1+395219 LINEAR 1286561 and LINEAR 2602707

Spatial evolution of friction of a textured wafer surface

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Friction 2013年第1期1卷 92-97页

作者： Huaping XIAO Ke WANg grant fox michel BELIN Julien FONTAINE Hong LIANg mechanical Engineering Texas A&M UniversityCollege StationTexas 77843USA materials Science and Engineering Texas A&M UniversityCollege StationTexas 77843USA Ecole Centrale de Lyon/CNRS-UmR 5513 France

mechanical failure of integrated circuits and micro-electro-mechanical systems(mEmS)demands new understanding of friction in small *** present research,we demonstrated an in situ approach to measure sliding friction of a patterned surface composing multi-materials and *** effects of materials and surface morphology on friction and electrical contact resistance were *** material transfer at the interface of dissimilar materials was found to play dominating roles in *** current work provides important insights from the fundamentals of friction that benefit the design of new micro-devices.

关键词： micro-electro-mechanical systems(mEmS) patterned wafers friction transfer wear electrical contact resistance

Controlled molecular Assembly of Tetrazine Derivatives on Surfaces

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CCS Chemistry 2022年第1期4卷 162-172页

作者： Shuo Wang Shuang Liu Audrey Sulkanen Joseph m.fox Xinqiao Jia gang-yu Liu Department of Chemistry University of CaliforniaDavisCA 95616 Department of material Science and Engineering University of DelawareNewarkDE 19716 Department of Chemistry and Biochemistry University of DelawareNewarkDE 19716

While self-assembly is relatively well-known and widely used to form hierarchical structures and thin film coatings,controlled assembly is less known and *** prior work has demonstrated the concept of controlled assembly of macromolecules such as star polymers[molecular weight(m_(w))∼383 kDa,hydrodynamic radius R∼13.8 nm]in *** work extends this concept to smaller molecules,in this case,poly(ethylene glycol)bis-tetrazine(PEgbisTz,m_(w) 8.1 kDa,R∼1.5 nm).The key to controlled molecular assembly is to first deliver ultrasmall volumes(sub-fL)of solution containing PEg-bisTz to a *** solvent evaporates rapidly due to the minute volume,thus forcing the assembly of solute,whose overall size and dimension are dictated by the initial liquid geometry and *** prepatterned surfaces,this work revealed that the initial liquid shape can be further tuned,and we could control the final assembly of solute such as PEgbisTz *** degree of control was demonstrated by varying the micropatterns and delivery *** work demonstrated the validity of controlled assembly for PEg-bisTz and enables three-dimensional(3D)nanoprinting of functional *** technology has promising applications in nanophotonics,nanoelectronics,nanocomposite materials,and tissue engineering.

关键词： tetrazine controlled assembly 3D nanoprinting atomic force microscopy microfluidic trans-cyclooctene

Rubber Tree Distribution mapping in Northeast Thailand

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International Journal of geosciences 2011年第4期2卷 573-584页

作者： Zhe Li Jefferson m. fox 不详

In many parts of mainland Southeast Asia rubber plantations are expanding rapidly in areas where the crop was not historically found. monitoring and mapping the distribution of rubber trees in the region is necessary for developing a better understanding of the consequences of land-cover and land-use change on carbon and water cycles. In this study, we conducted rubber tree growth mapping in Northeast Thailand using Landsat 5 Tm data. A mahalanobis typicality method was used to identify different age rubber trees. Landsat 5 Tm 30 m non-thermal reflective bands, NDVI and tasseled cap transformation components were selected as the model input metrics. The validation was carried out using provincial level agricultural statistical data on the rubber tree growth area. At regional (Northeast Thailand) and provincial scales, the estimates of mature and middle-age rubber stands produced from 30 m Landsat 5 Tm data compared well (high statistical significance) with the provincial rubber tree growth statistical data.

关键词： Northeast Thailand Rubber Tree mapping Land-Use and land-Cover Change mahalanobis Typicality Kauth-Thomas Transformation Landsat 5 Tm

Estimation of flea beetle damage in the field using a multistage deep learning-based solution

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Artificial Intelligence in Agriculture

Artificial Intelligence in Agriculture 2024年第3期13卷 18-31页

作者： Arantza Bereciartua-Pérez maría monzón Daniel múgica greta De Both Jeroen Baert Brittany Hedges Nicole fox Jone Echazarra Ramón Navarra-mestre TECNALIA Basque Research and Technology Alliance(BRTA)Parque Tecnológico de BizkaiaAstondo Bidea.Edificio 70048160 DerioBizkaiaSpain BASF SE Speyererstrasse 267117 LimburgerhofGermany BASF Belgium(BBCC-Innovation Center gent) Technologiepark-Zwijnaarde 1019052 GentBelgium BASF Canada Inc 51028 Quarry Park Blvd SECalgaryAlberta T2C 4P5Canada

Estimation of damage in plants is a key issue for crop ***,experts in the field manually assess the *** is a time-consuming task that can be automated thanks to the latest technology in computer vision(CV).The use of image-based systems and recently deep learning-based systems have provided good results in several agricultural *** image-based applications outperform expert evaluation in controlled environments,and now they are being progressively included in non-controlled field applications.A novel solution based on deep learning techniques in combination with image processingmethods is proposed to tackle the estimate of plant damage in the *** proposed solution is a two-stage *** a first stage,the single plants in the plots are detected by an object detection YOLO based *** a regression model is applied to estimate the damage of each individual *** solution has been developed and validated in oilseed rape plants to estimate the damage caused by flea *** crop detection model achieves a mean precision average of 91%with a mAP@0.50 of 0.99 and a mAP@0.95 of 0.91 for oilseed rape *** regression model to estimate up to 60%of damage degree in single plants achieves a mAE of 7.11,and R2 of 0.46 in comparison with manual evaluations done plant by plant by *** are deployed in a docker,and with a REST API communication protocol they can be inferred directly for images acquired in the field from a mobile device.

关键词： Convolutional neural networks Deep learning Plant phenotyping Damage estimation Plant crop detection and identification