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Feeding behavior, life history, and virus transmission ability of Bemisia tabaci Mediterranean species (Hemiptera: Aleyrodidae) under elevated CO2

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Insect Science 2020年第3期27卷 558-570页

作者： Ainara Penalver-Cruz Elisa Garzo Ines Prieto-Ruiz Miguel diaz-Carro Ana Winters aranzazu Moreno Alberto Fereres departamento de Proteccion vegetal Instituto de Ciencias Agrarias(ICA-CSIC)MadridSpain Laboratorio de Control Biologico Instituto de Ciencias BiologicasUniversidad de TalcaTalcaChile Institute of Biological Environmental and Rural SciencesAberystwyth UniversityAberystwythCeredigionUK

The continuous rise of CO2 concentrations in the atmosphere is reducing plant nutritional quality for herbivores and indirectly affects their *** whitefly(Bemisia tabaci,Gennadius)is a major worldwide pest of agricultural crops causing significant yield *** study investigated the plant‐mediated indirect effects of elevated CO2 on the feeding behavior and life history of *** Mediterranean *** were grown under elevated and ambient CO2 concentrations for 3 weeks after which plants were either used to monitor the feeding behavior of whiteflies using the Electrical Penetration Graph technique or to examine fecundity and fertility of *** leaf carbon,nitrogen,phenols and protein contents were also analyzed for each *** tabaci feeding on plants exposed to elevated CO2 showed a longer phloem ingestion and greater fertility compared to those exposed to ambient CO2 suggesting that *** is capable of compensating for the plant nutritional ***,this study looked at the transmission of the virus Tomato yellow leaf curl virus(Begomovirus)by *** exposing source and receptor tomato plants to ambient or elevated CO2 levels before or after virus transmission *** indicate that *** transmitted the virus at the same rate independent of the CO2 levels and plant ***,we conclude that *** Mediterranean species prevails over the difficulties that changes in CO2 concentrations may cause and it is predicted that under future climate change conditions,*** would continue to be considered a serious threat for agriculture worldwide.

关键词： carbon dioxide eggplant EPG fitness tomato whiteflies

STRUCTURAL PROPERTIES INVESTIGATION ON MICROCRYSTALLINE SILICON FILMS dEPOSITEd WITH VHF-PECVd TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 223-227页

作者： H.d.Yang departmentofElectronicEngineering JinanUniversityGuangzhou510632China

Raman scattering spectroscopy and scanning electron microscopy (SEM) techniques were used to determine the structural properties of two typical series of microc rystalline silicon (μc-Si:H) films deposited at different VHF plasma power and different working gas pressure by very high frequency plasma enhanced chemical v apor deposition (VHF-PECVd) technique. Raman spectra measurements show that both crystalline volume fraction Xc and average grain size d of μc-Si : H films ar e strongly affected by the two deposition conditions and are more sensitive to w orking gas pressure than VHF plasma power. SEM characterizations have further co nfirmed that VHF plasma power and working gas pressure could clearly enhance the surface roughness of μc-Si : H films ascribing to polymerization reactions, w hich is also more sensitive to working gas pressure than VHF plasma power.

关键词： VHF-PECVd microcrystalline silicon film structural property

Anterior Mitral Valve Orifice in a dog

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Open Journal of Veterinary Medicine 2021年第3期11卷 117-123页

作者： Başar Ulaş Sayilkan Yücel Meral Emre Küllük duygu dalgin department of Internal Medicine Faculty of Veterinary Medicine Ondokuz May&#305s University Samsun Turkey

The patient was admitted to OndokuzMayıs University Animal Hospital Internal Medicine outpatient clinic with complaints of epileptic seizures and hypothyroidism. A description of the patient’s owner is available in the history information. There was no physician information. Bradycardia was found in the electrocardiography of the patient. 2-D, M-Mode, PW, CW and Color doppler examinations were performed. Left-ventricular hypokinetic and mitral and tricuspidal valve movements were observed with limited M-Mode imaging. Anterior mitral orifice of 2 mm width was detected on septal mitral valve by PW doppler and color doppler. With this orifice, the presence of regurgitant jet, which covers LA at a rate of 1/3 and was 3.2 m/sec, together with mitral regurgitation (0.5 m/sec.), was demonstrated. PISA calculations;VFR (mL/s), ERO (mm2) and RVol (mL/pulse) values were calculated as if there were mitral regurgitation and data were obtained for mild-moderate mitral regurgitation. Therefore, no operative treatment of the orifice was recommended. Mitral valve orifice is a rare pathology and this is the first report in canine veterinary practice with degenerative mitral valve disorder. We aimed to underline the possibility of mitral orifice development in degenerative mitral valve disorders, known to present with vegetations and varying degrees of prolapsus, conventionally.

关键词： dog Echocardiography Anterior Mitral Valve Orifice degenerative Mitral Valve disorder Mitral Regurgitation doppler Echocardiography

Optimal harvesting for a single-species population governed by Gompertz law:Influence of environmental fluctuation and limited harvesting capacity

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International Journal of Biomathematics 2019年第2期12卷 115-142页

作者： P.d.N.Srinivasu Simon d.Zawka Sri Sathya Sai University for Human Excellence Navanihala Village Okali PostKamalapur Taluk Gulbarga DistrictKarnataka 585313India department of Mathematics Andhra University Visakhapatnam 530003India department of Mathematics Ar ba Minch University Arba MinchEthiopia

This work presents an optimal harvesting problem associated with a single-species population governed by Gompertz law in a seasonally fluctuating *** influence of environmental fluctuation is accommodated by choosing the coefficients in the differential equation to be periodic functions with the same period and restriction on the harvesting effort is accommodated by considering binding constraints on the control ***,a linear optimal control problem has been considered where the state dynamics is governed by Gompertz equation and the control variable is subject to the binding *** the help of maximum principle and the concept of blocked intervals,an optimal periodic solution has been obtained which is followed by the construe tion of optimal solution using the theory of most rapid *** results of the study are demonstrated through numerical simulations.

关键词： Optimal harvesting Gompertz equation seasonality binding constraint blocked intervals

Non-Uniform Axial Electric Field in argon Glow discharge Plasma

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Chinese Physics Letters 2006年第5期23卷 1234-1237页

作者： d. Akbar S. Bilikmen department of Physics Middle East Technical University 06531 Ankara Turkey

The non-uniform argon dc glow discharge plasma system has been constructed in a very special design to investigate the effects of variable tube radius on plasma parameters. By using isolated computer controlled three couples of a double probe （TCdP） system, the electron temperature, electron density, the reduced electric field, and electron drift velocity are measured at low and intermediate pressures. It is shown that the electron temperature and reduced electric field （density） decreases （increases） as the radius decreases, at low discharge current and pressures. For large radius regions, at high discharge currents and pressures, the behaviour of the plasma parameters of specially reduced electric field change similarly to those in a uniform discharge system.

关键词： POSITIVE-COLUMN GAS-dISCHarGES ION-BOMBardMENT LANGMUIR PROBE Pd FILMS PRESSURE MOdEL ar ParAMETERS

Microfluidics Based Optical Biosensor for Rapid detection of Escherichia coli O157:H7

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Microfluidics Based Optical Biosensor for Rapid Detection of...

Elements of automated survey of pavements and a 3d methodology

国际农业工程大会

作者： Yanbin Li Professor Ph.d.department of Biological and Agricultural Engineering University of arkansas 203 Engineering Hall Fayetteville ar 72701 USA Xiao-li Su Research Associate Ph.d.department of Biological and Agricultural Engineering University of arkansas O-114 Poultry Science Building Fayetteville ar 72701 USA

＜正＞ Food safety still remains a major concern of our society. Food products contaminated with pathogens, such as E. coli O157.-H7, may result in foodborne diseases, product recalls and international trade barriers. However, currently applied microbial plating, ELISA and PCR methods are time-consuming and laboratory-centered, and they cannot meet the challenge of rapid food processing and distribution systems. Therefore, the objective of this research was to develop a portable biosensor, based on microfluidics for bioseparation/bioreaction, for rapid, on line or on site detection of E. coli O157:H7 and other foodborne pathogens.

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Journal of Modern Transportation 2011年第1期19卷 51-57页

作者： Kelvin C.P.WANG Civil Engineering University of Arkansas

Sound transportation infrastructure is critical for economic development and sustainability. Pavement condition is a primary concern among agencies of the roadway infrastructure. Automation has become possible in recent years on collecting data and producing results for certain aspects of pavement performance, while challenges remain in several other categories, such as automated cracking survey. This paper reviews the technological advances on automated survey of pavements, and discusses the most recent breakthroughs by the team led by the author in using 3d laser imaging for capturing 1 mm surface images of pavements.

关键词： pavements automated survey 3d methodology surface images

Monte Carlo sampling for error propagation in linear regression and applications in isochron geochronology

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Science Bulletin 2019年第3期64卷 189-197页

作者： Yang Li Shuang Zhang Richard Hobbs Camila Caiado Adam d.Sproson david Selby Alan d.Rooney State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences department of Earth Sciences Durham University department of Geology and Geophysics Yale University department of Mathematical Sciences Durham University Atmosphere and Ocean Research Institute The University of Tokyo

Geochronology is essential for understanding Earth's history. The availability of precise and accurate isotopic data is increasing; hence it is crucial to develop transparent and accessible data reduction techniques and tools to transform raw mass spectrometry data into robust chronological data. Here we present a Monte Carlo sampling approach to fully propagate uncertainties from linear regressions for isochron dating. Our new approach makes no prior assumption about the causes of variability in the derived chronological results and propagates uncertainties from both experimental measurements(analytical uncertainties) and underlying assumptions(model uncertainties) into the final age *** synthetic examples, we find that although the estimates of the slope and y-intercept(hence age and initial isotopic ratios) are comparable between the Monte Carlo method and the benchmark‘‘Isoplot" algorithm, uncertainties from the later could be underestimated by up to 60%, which are likely due to an incomplete propagation of model uncertainties. An additional advantage of the new method is its ability to integrate with geological information to yield refined chronological constraints. The new method presented here is specifically designed to fully propagate errors in geochronological applications involves linear regressions such as Rb-Sr, Sm-Nd, Re-Os, Pt-Os, Lu-Hf, U-Pb(with discordant points),Pb-Pb and ar-ar.

关键词： Linear regression Isochron Geochronology Uncertainty propagation Monte Carlo Isoplot

PECVd OF Hard ANd ELASTIC BCN COATINGS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 15-20页

作者： R. Cremer d. Kurapov C. Martinez O. Kyrylov d. Neuschutz LebrstuhL fir Theoretische Hüttenkunde RWTH

Compounds of the B-C-N system are very promising to produce superhardcoatings with good tribological, chemical and thermal properties. Consequently, BCN films wereprepared by plasma enhanced chemical vapor deposition (PECVd). The films were deposited from gaseousmixtures of BCI_3-C_2H_4-N_2-H_2-ar in different unipolar and bipolar pulsed glow discharges at 550deg C and analyzed with respect to composition, electronic structure and mechanical properties. Themicrostructure and composition of the BCN films were determined by scanning electron microscopy(SEM), X-ray diffraction (XRd), X-ray photoelectron spectroscopy (XPS) and reflection electronenergy loss spectroscopy (REELS). Mechanical properties were characterized using both thetraditional Vickers method and nanoindentation. The films, that were deposited using a bipolarpulsed generator, were weak and had a sponge-like structure, whereas the films prepared using anunipolar generator were well adherent, had a hardness of more than 11GPa and very high elasticrecoveries of up to 80 percent. The elasticity properties supposedly result from the formation of afullerene-like structure.

关键词： boron carbonitride PECVd XPS X-ray diffraction microstructure