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Epistasis and maternal Effect in Resistance to Puccinia coronata ***. avenae Eriks in Oats(Avena sp.)

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Agricultural Sciences in China 2010年第10期9卷 1462-1466页

作者： Bnejdi f Hammami I Allagui m B Saadoun m el Gazzah m Laboratoire de Génétique et Biométrie faculté des Sciences de Tunis Université Tunis Institut National de la Recherche Agronomique de Tunisie(INRAT) Rue Hadi Karray

The objective of this paper was to investigate the mode of heredity for resistance in oats （Avena sp.） to crown rust caused by Puccinia coronata Cda. f. sp. avenae Eriks, Eight generations of 2 crosses were used to estimate genetic effects and narrow-sense heritability （NSH）. Separate generation means analysis （GmA） indicated a complex gene action controlling this trait with additive, dominance, epistatic and maternal effects （mE）. The genetic model which assumed no epistasis and no mE did not accurately describe the resistance to P. coronata. In both crosses, the digenic epistatic model with mE was sufficient to explain variation in generation means for isolate CRec58 and isolate CRec46. Additive dominance and epistatic components were negative in most cases, suggesting that gene effects contributed more to the resistance than to the susceptibility. The estimated values of NSH were 15-99% depending upon the cross and isolates. The results indicated that appropriate choice of maternal parent and recurrent selection would increase resistance to crown rust in oats.

关键词： epistasis heritability maternal effect resistance

Thick and Dense Anodic Oxide Layers formed on Aluminum in Sulphuric Acid Bath

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Journal of materials Science & Technology 2010年第2期26卷 113-118页

作者： W. Bensalah m. feki m. Wery H.f. Ayedi URCIm Department of Materials EngineeringNational School of Engineering IUT Orsay-Paris XI University Plateau du Moulon URCIm Department of Materials Engineering National School of Engineering

Thick and dense oxide layers were obtained on aluminium in sulphuric acid electrolyte. for this purpose, the methodology of experimental design was used. A three-variables Doehlert design （bath temperature, anodic current density, sulphuric acid concentration）, was achieved. In order to maximize the growth rate and the density of the anodic oxide layer, optimum path study was conducted. Under the determined optimal anodizing conditions （5.7℃, 3 ***-2,Csul=140 g.L-1）, the estimated response values were 0.86 μmin-1 and 3.12 ***-2 for growth rate and density, respectively. The morphology of optimum layer was examined by scanning electron microscopy （SEm）. The compactness of the optimum anodic layer can be correlated with its morphology revealed by SEm observations.

关键词： Sulphuric anodization Experimental design Growth rate Density

Telomeres:Linking stress and survival,ecology and evolution

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Current Zoology 2010年第6期56卷 714-727页

作者： mark f.HAUSSmANN Nicole m.mARCHETTO Department of Biology Bucknell University

Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular and cellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, we discuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize current knowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interest- ing new connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices of physiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way that glucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. future work needs to establish and explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found, it provides an explanatory mechanism by which environmental perturbation impacts life history trajectories [Current Zoology 56 （6）： 714-727, 2010].

关键词： Corticosterone Stress Survival Telomeres

Landau damping in a bounded magnetized plasma column

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Chinese Physics B 2015年第2期24卷 287-294页

作者： H.Zakeri-Khatir f.m.Aghamir Department of Physics University of Tehran

The damping decrement of Landau damping and the effect of thermal velocity on the frequency spectrum of a propagating wave in a bounded plasma column are *** magnetized plasma column partially filling a cylindrical metallic tube is considered to be collisionless and *** Landau damping is due to the thermal motion of charge carriers and appears whenever the phase velocity of the plasma waves exceeds the thermal velocity of *** analysis is based on a self-consistent kinetic theory and the solutions of the wave equation in a cylindrical plasma waveguide are presented using Vlasov and maxwell *** hybrid mode dispersion equation for the cylindrical plasma waveguide is obtained through the application of appropriate boundary conditions to the plasma-vacuum *** dependence of Landau damping on plasma parameters and the effects of the metallic tube boundary on the dispersion characteristics of plasma and waveguide modes are investigated in detail through numerical calculations.

关键词： Landau damping cylindrical plasma waveguide Vlasov equation dispersion characteristic

Combined Effect of magnetic field and Thermal Dispersion on a Non-Darcy mixed Convection

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Journal of Thermal Science 2011年第3期20卷 276-282页

作者： m. f. EI-Amin Shuyu Sun Computational Transport Phenomena Laboratory （CTPL） Division of Physical Sciences and Engineering （PSE）King Abdullah University of Science and Technology （KAUST） Thuwal 23955-6900 Jeddah Kingdom of Saudi Ara-bia mathematics Department Faculty of Science South Valley University Aswan 81528 EGYPT

This paper is devoted to investigate the influences of thermal dispersion and magnetic field on a hot semi-infinite vertical porous plate embedded in a saturated Darcy-forchheimer-Brinkman porous medium. The coefficient of thermal diffusivity has been assumed to be the sum of the molecular diffusivity and the dynamic diffusivity due to mechanical dispersion. The effects of transverse magnetic field parameter (Hartmann number Ha), Reynolds number Re (different velocities), Prandtl number Pr (different types of fluids) and dispersion parameter on the wall shear stress and the heat transfer rate are discussed.

关键词： Thermal dispersion non-Darcy convection magneto-hydro-dynamics porous media geothermal systems

Cognition and the brain of brood parasitic cowbirds

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Integrative Zoology 2019年第2期14卷 145-157页

作者： David f.SHERRY mélanie f.GUIGUENO Department of Psychology Western University LondonOntario Department of Natural Resource Sciences McGill UniversityMontrealQuebecCanada

Cowbirds are brood *** lay their eggs in the nests of other species,which then incubate the cowbird eggs and raise the young *** and returning to heterospecific nests presents cowbirds with several cognitive *** some species,such as brown-headed cowbirds(molothrus ater),females but not males search for and remember the locations of potential host *** describe recent research on sex differences in cognition and the hippocampus associated with this sex difference in search for host *** brown-headed cowbirds perform better than males on some,but not all,tests of spatial memory and females show a pattern of adult hippocampal neurogenesis not found in males or in closely related non-parasitic *** of the apparent specialization of the hippocampus,brown-headed cowbirds may be a good model in which to examine spatial information processing in the avian hippocampus and we also describe recent research on the spatial response properties of brown-headed cowbird hippocampal neurons.

关键词： adult neurogenesis brood parasites cowbirds hippocampus sex differences spatial memory

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： m.füle A.P.Kovács T.Gilinger m.Karnok P.Gaál S.figul G.marowsky K.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm.for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

A photonic crystal L-shaped bend based on ring resonators

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Chinese Optics Letters 2008年第10期6卷 713-714页

作者： m.Djavid f.monifi A.Ghaffari m.S.Abrishamian Department of Electrical Engineering K.N.Toosi University of TechnologyTehranIran

We propose a new type of two-dimensional （2D） photonic crystal L-shaped bent waveguides based on ring resonators with an acceptable bandwidth. The proposed structure mechanism is based on coupling between a waveguide and a ring resonator. This structure is designed and verified by finite-difference time-domain （fDTD） computation. Our simulation using this method gets over 90% output.

关键词： ring A photonic crystal L-shaped bend based on ring resonators fDTD

Holmium Oxide film as a Saturable Absorber for 2μm Q-Switched fiber Laser

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Chinese Physics Letters 2017年第5期34卷 48-51页

作者： m.f.A.Rahman m.f.m.Rusdi m.Q.Lokman m.B.H.mahyuddin A.A.Latiff A.H.A.Rosol K.Dimyati S.W.Harun Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia faculty of Electrical Engineering University Teknologi Mara Shah Alam 40450 Malaysia

This work reports on the use of the holmium oxide （Ho2O3） polymer film as a saturable absorber （SA） for generating stable Q-switching pulses operating in a 2μm region in a thulium-doped fiber laser cavity. The SA is prepared by diluting a commercial Ho3O2 powder and then mixing it with polyvinyI alcohol （PVA） solution to form a Ho2O3-PVA film. A tiny part of the film about 1mm×1 mm in size is sandwiched between two fiber ferrules with the help of index matching gel. When incorporated in a laser cavity driven by a 1552-nm pump, stable Q-switching pulses are observed at 1955nm within the pump power range of 363 491 roW. As the pmnp power increases within this range, the repetition rate rises from 26 kHz to 39 kHz, as the pulse width drops from 4.22μs to 2.57μs. The laser operates with a signal-to-noise ratio of 47dB, and the maximum output power and the pulse energy obtained are 2.67mW and 69ng, respectively. Our results successfully demonstrate that the Ho2O3 film can be used as a passive SA to generate a 2μm pulse laser.

关键词： m Q-Switched fiber Laser SA fESEm