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Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes

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Current Zoology 2014年第6期60卷 804-815页

作者： Hubert SCHWABL Willow r. LINDSAY Douglas G. BArrON Michael S. WEBSTEr School of Biological Sciences and Center for reproductive Biology Washington State University Pullman WA 99164-4236 USA Department of Department of Biological and Environmental Sciences Goteborg University Box 463405 30 Goteborg Sweden Department of Psychology University of South Florida Tampa FL 33620-7200 USA Department of Neurobiology and Behavior and Comell Laboratory for Ornithology Comell University Ithaca NY 14850 USA

While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.

关键词： Androgen Estrogen Glucocorticoid Mate choice Promiscuity Alternative phenotypes

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Cirrus Cloud Macrophysical and Optical Properties over North China from CALIOP Measurements

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Advances in Atmospheric Sciences 2011年第3期28卷 653-664页

作者：闵敏王普才 James r. Campbell 宗雪梅夏俊荣 Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences UCAr Visiting Scientist Programs Naval Research LaboratoryMontereyCaliforniaUSA

Two years of mid-latitude cirrus cloud macrophysical and optical properties over North China are described from Earth-orbiting Cloud-Aerosol Lidar with Orthogonal Polarization(CALIOP) satellite measurements. Global cloud climatological studies based on active remote sensing data sets benefit from more accurate resolution of vertical structure and more reliable detection of optically thin *** mean values for cirrus cases over North China are 0.19±0.18 for infrared emittance,0.41±0.68 for visible optical depth, 0.26±0.12 for integrated depolarization ratio,and 0.72±0.22 for integrated color *** studied using reasonable assumptions for the relationship between extinction and ice crystal backscatter coefficients,our results show that most of the cirrus clouds profiled using the 0.532μm channel data stream correspond with an optical depth of less than *** dependence of cirrus cloud properties on cirrus cloud mid-cloud temperature and geometry thickness are generally similar to the results derived from the ground-based lidar, which are mainly impacted by the adiabatic process on the ice cloud ***,the differences in macrophysical parameter variability indicate the limits of spaceborne-lidar and dissimilarities in regional climate variability and the nature and source of cloud nuclei in different geographical regions.

关键词： cirrus cloud spaceborne-lidar optical depth

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Generalized Linear Model with Elastic Net regularization and Convolutional Neural Network for Evaluating Aphanomyces root rot Severity in Lentil

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Plant Phenomics 2020年第1期2卷 378-388页

作者： Afef Marzougui Yu Ma rebecca J.McGee Lav r.Khot Sindhuja Sankaran Department of Biological Systems Engineering Washington State UniversityPullmanWAUSA Department of Horticulture Washington State UniversityPullmanWAUSA United States Department of Agriculture-Agricultural research Service Grain Legume Genetics and Physiology Research UnitWashington State UniversityPullmanWAUSA

Phenomics technologies allow quantitative assessment of phenotypes across a larger number of plant genotypes compared to traditional phenotyping *** utilization of such technologies has enabled the generation of multidimensional plant traits creating big ***,to harness the power of phenomics technologies,more sophisticated data analysis methods are *** this study,Aphanomyces root rot(Arr)resistance in 547 lentil accessions and lines was evaluated using red-Green-Blue(rGB)images of *** created a dataset of 6,460 root images that were annotated by a plant breeder based on the disease *** approaches,generalized linear model with elastic net regularization(EN)and convolutional neural network(CNN),were developed to classify disease resistance categories into three classes:resistant,partially resistant,and *** results indicated that the selected image features using EN models were able to classify three disease categories with an accuracy of up to 0:91±0:004(0:96±0:005 resistant,0:82±0:009 partially resistant,and 0:92±0:007 susceptible)compared to CNN with an accuracy of about 0:84±0:009(0:96±0:008 resistant,0:68±0:026 partially resistant,and 0:83±0:015 susceptible).The resistant class was accurately detected using both classification ***,partially resistant class was challenging to detect as the features(data)of the partially resistant class often overlapped with those of resistant and susceptible ***,the findings provided insights on the use of phenomics techniques and machine learning approaches to provide quantitative measures of Arr resistance in lentil.

关键词： classify Elastic roots

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Sign-Changing and Multiple Solutions Theorems for Semilinear Elliptic Boundary Value Problems with Jumping Nonlinearities

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Acta Mathematica Sinica,English Series 2000年第1期16卷 113-122页

作者： Shujie Li Zhitao Zhang Institute of Mathematics,Academia Sinica,Beijing 100080,P.r.China Institute of Mathematics Academia Sinica Beijing 100080 P.R. China

In this paper,we use the ordinary differential equation theory of Banach spaces and minimax theory,and in particular,the relative mountain pass lemma to study semilinear elliptic boundary value problems with jumping nonlinearities at zero or infinity,and get new multiple solutions and sign- changing solutions theorems,at last we get up to six nontrivial solutions.

关键词： Sign-changing solutions Dirichlet problems Multiple solutions Jumping nonlinearities

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Magnetohydrodynamic flow and heat transfer of a hybrid nanofluid over a rotating disk by considering Arrhenius energy

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Communications in Theoretical Physics 2021年第4期73卷 9-20页

作者： M Gnaneswara reddy Naveen Kumar r B C Prasannakumara N G rudraswamy K Ganesh Kumar Department of Mathematics Acharya Nagarjuna University CampusOngole-523001India Department of Studies and research in Mathematics Davangere UniversityShivagangothriDavangere-577007KarnatakaIndia Department of Mathematics P.C.Jabin Science CollageHubballi-580031India

This research work explores the effect of hybrid nanoparticles on the flow over a rotating disk by using an activation energy ***,we considered molybdenum disulfide and ferro sulfate as nanoparticles suspended in base fluid *** magnetic field is pragmatic normal to the hybrid nanofluid flow *** derived nonlinear ordinary differential equations are non-dimensionalized and worked out numerically with the help of Maple software by the rKF-45 *** scientific results for a non-dimensionalized equation are presented for both nanoparticle and hybrid nanoparticle *** of various predominant restrictions on flow and thermal fields are *** estimation for friction factor,local Nusselt number and Sherwood number are also *** reveal that the reduction of the heat transfer rate is greater in hybrid nanoparticles when compared to nanoparticles for increasing values of Eckert Number and the thermal field enhances for the enhanced values of volume fraction.

关键词： porous medium MHD hybrid nanoparticles activation energy

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Conductivity and dielectric studies on LiCeO_2

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Journal of rare Earths 2010年第3期28卷 435-438页

作者： M.Prabu S.Selvasekarapandian A.r.Kulkarni G.Hirankumar C.Sanjeeviraja Department of Metallurgical Engineering and Material Science Indian Institute of Technology Bombay Department of Physics Kalasalingam University Department of Physics Alagappa University

LiCeO2 was prepared by a solid-state reaction method using microwave heat treatment and identified by X-ray ***2 has monoclinic crystal structure whose conductivity and dielectric properties were studied over a range of frequency(42 Hz to 1 MHz) and temperatures(30-500 °C) using ac technique of complex impedance analyzer HIOKI *** impedance and modulus plots were used as tools to analyze the sample behaviour as a function of frequency at different *** ***...

关键词： lithium-ion batteries impedance conductivity dielectric analysis complex modulus rare earths

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Isovector pairing and particle-number fluctuation effects on the spectroscopic factors of one-proton stripping and one-neutron pick-up reactions in proton-rich nuclei

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Chinese Physics C 2018年第8期42卷 137-158页

作者： Y.Benbouzid N.H.Allal M.Fellah M.r.Oudih Laboratoire de Physique Theorique-Facultéde Physique-USTHB BP32 El-Alia16111 Bab-Ezzouar-Alger-Algeria

Expressions of the spectroscopic factors（SFs） corresponding to one-particle transfer reactions have been established using a schematic *** expressions have been derived by taking into account the isovector neutron-proton（np） pairing correlations and a particle-number projection in the framework of the generalized SharpBCS（SBCS） *** proposed expressions of the projected wave-functions of odd-mass nuclei have been used for this *** formalism has first been tested using the single-particle energies of the schematic picketfence *** is shown that the np pairing and particle-number fluctuation effects are far from negligible and they depend on the pairing gap parameter *** behavior is not the same when the parent nuclei are even-even or *** dealing with the SFs corresponding to one-proton stripping and one-neutron pick-up reactions in proton-rich nuclei have then been established within the framework of the realistic Woods-Saxon *** is shown that the np pairing effect as well as the particle-number projection effect are important and thus have to be included in future calculations of the SF corresponding to these kinds of reactions.

关键词： neutron-proton pairing particle-number projection spectroscopic factor

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Multi-Modality Medical Image Fusion Based on Wavelet Analysis and Quality Evaluation

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Journal of Systems Engineering and Electronics 2001年第1期12卷 42-48页

作者： Yu Lifeng & Zu Donglin Institute of Heavy Ion Physics, Peking University, 100871, P. r. China Wang Weidong General Hospital of PLA, Beijing 100853, P. r. China Bao Shanglian Institute of Heavy Ion Physics, Peking University, 100871, P. r. China Institute of Heavy Ion Physics Peking University 100871 P. R. China General Hospital of PLA Beijing 10085. P. R. China

Multi-modality medical image fusion has more and more important applications in medical image analysis and understanding. In this paper, we develop and apply a multi-resolution method based on wavelet pyramid to fuse medical images from different modalities such as PET-MrI and CT-MrI. In particular, we evaluate the different fusion results when applying different selection rules and obtain optimum combination of fusion parameters.

关键词： Computer simulation Computerized tomography Image analysis Image quality Image understanding Magnetic resonance imaging Optical resolving power

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Separate basolateral and apical phosphatidylcholine secretion routes in intestinally differentiated tumor cells

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World Journal of Gastroenterology 2009年第46期15卷 5821-5826页

作者： Daniel Gotthardt Annika Braun Anke Tietje Karl Heinz Weiss robert Ehehalt Wolfgang r Stremmel Department of Gastroenterology University Hospital Heidelberg

AIM:To investigate whether the secretion of phospha-tidylcholine(PC)in intestinal mucus occurs by apical secretion or via basolateral excretion and to determine its subsequent passage across the tight junctions to the apical ***:We addressed this question using the po-larized intestinally differentiated tumor cell line CaCo-2 grown on filters to confluence in Transwell culture *** released PC and sphingomyelin(Sph)from apical and basolateral media were analyzed by mass ***:The secreted PC species were identical in both compartments indicating the same intracellular origin of ***,PC secretion into the basolateral compart-ment was more effective,and the PC:Sph ratio in the ba-solateral compartment was signif icantly higher than that in the apical compartment(8.18 ± 1.84 vs 4.31 ± 1.22,P = 0.01).Both pathways were temperature sensitive and were unaltered in the presence of ***:The data demonstrate the PC secre-tion capacity of CaCo-2 cells and indicate two sepa-rated apical and basolateral release mechanisms.

关键词： CaCo-2 cells Epithelial cells Mass spectrometry Phosphatidylcholine Secretion Sphingomyelin

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Structural and micro structural studies of PbO-doped SnO_2 sensor for detection of methanol, propanol and acetone

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Journal of Natural Gas Chemistry 2011年第2期20卷 179-183页

作者： J. K. Srivastava Preeti Pandey V. N. Mishra r. Dwivedi Center for research in Microelectronics Department of Electronics Engineering Institute of Technology Banaras Hindu University

In the present work the structural information of PbO-doped SnO2 thick film sensor has been investigated with X-ray diffractometer （XrD） and scanning electron microscope （SEM）. Initially, SnO2 powder was derived using sol-gel process and was subsequently doped with PbO and ground up to nanosized particles. A suitable gas sensor structure was fabricated on 1′′×1′′ alumina substrate using thick film technology. The necessary paste for screen printing was also developed. SEM results showed sol-gel derived powder gets more agglomerated in the thick film form. The sensitivity of the sensor has been investigated at different temperatures （150 ？C？350 ？C） upon exposure to methanol, propanol and acetone, yielding a maximum at 250 ？C for acetone with 1 wt% PbO-doping while at 350 ？C for propanol with 3 wt% PbO-doping of the sensor. The reduction of particle size to nanometers （validated through XrD） leads to a dramatic improvement in sensitivity of sensors for the chosen organic vapors. The results also correlate well with the microstructural properties of the material and the dopant.

关键词： gas sensor nanosized SnO2 Sol-gel thick film

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