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Identifying female phenotypes that promote behavioral isolation in a sexually dimorphic species of fish Etheostoma zonale

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Current Zoology 2021年第2期67卷 225-236页

作者： Natalie S.ROBERTS Tamra C.MENDELSON Department of Biological Sciences University of Maryland Baltimore CountyBaltimoreMD21250USA

In sexually dimorphic species characterized by exaggerated male ornamentation,behavioral isola-tion is often attributed to female preferences for conspecific male ***,in a number of sexu-ally dimorphic species,male mate choice also results in behavioral *** many of these cases,the female traits that mediate species boundaries are *** in sexually dimorphic species typically lack many of the elaborate traits that are present in males and that are often used for taxonomic classification of *** a diverse and largely sexually dimorphic group of fishes called darters(Percidae:Etheostoma),male mate choice contributes to behavioral isolation be-tween a number of species;however,studies addressing which female traits males prefer are *** this study,we identified the dominant female pattern for two sympatric species,Etheostoma zonale and Etheostoma barrenense,using pattern energy analysis,and we used discriminate func-tion analysis to identify which aspects of female patterning can reliably classify *** then tested the role of female features in male mate choice for ***,by measuring male preference for computer animations displaying the identified(species specific)conspecific *** found that the region above the lateral line is important in mediating male mate preferences,with males spending a significantly greater proportion of time with animations exhibiting conspecific female patterning in this region than with animations exhibiting heterospecific female *** results suggest that the aspects of female phenotypes that are the target of male mate choice are different from the conspicuous male phenotypes that traditionally characterize species.

关键词： darters discriminant function analysis Etheostoma female phenotype male mate choice 3D animations

Validating the use of computer animations in male Etheostoma zonale:a comparison of individual response to live and artificial stimuli

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Current Zoology 2019年第6期65卷 725-727页

作者： Natalie S.ROBERTS Caitlyn MCCAULLER Tamra C.MENDELSON Department of Biological Sciences University of Maryland Baltimore CountyBaltimoreMDUSA

The use of artificial stimuli in tests of animal behavior are common,and as technological advances increase,opportunities for the use of 3D computer animations in behavioral tests are becoming increasingly available(Witte et al.2017).The importance of easy-tomanipulate,consistent,and reliably performing stimuli is clear,and this is readily achievable with the use of computer *** of animated stimuli is critical,however,to ensure that behaviors observed in response to artificial,computer-generated stimuli are equivalent to what would be expected if animals were presented with a comparable live stimuli(Woo and Rieucau 2011;Chouinard-Thuly et al.2017;Powell and Rosenthal 2017).

关键词： computer artificial animation

Circadian Clock-Regulated Phosphate Transporter PHT4;1 Plays an Important Role in Arabidopsis Defense

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Molecular Plant 2011年第3期4卷 516-526页

作者： Guo-Ying Wang Jiang-Li Shi Gina Ng Stephanie L. Battle Chong Zhang Hua Lu Department of Biological Sciences University of Maryland Baltimore County 1000 Hilltop CircLe Baltimore MD 21250 USA

The Arabidopsis accelerated cell death 6-1 （acd6-1） mutant shows constitutive defense, cell death, and ex- treme dwarf phenotypes. In a screen for acd6-1 suppressors, we identified a mutant that was disrupted by a T-DNA in the PHOSPHATE TRANSPORTER 4;1 （PHT4;1） gene. The suppressor mutant pht4;1-1 is dominant, expresses truncated PHT4;1 transcripts, and is more susceptible to virulent Pseudomonas syringae strains but not to several avirulent strains. Treat- ment with a salicylic acid （SA） agonist induced a similar level of resistance in Col-0 and pht4;1-1, suggesting that PHT4;1 acts upstream of the SA pathway. Genetic analysis further indicates that PHT4,1 contributes to SID2-dependent and -in- dependent pathways. Transgenic expression of the DNA fragment containing the PHT4;1-1 region or the full-length PHT4;1 gene in wild-type conferred enhanced susceptibility to Pseudomonas infection. Interestingly, expression of PHT4;1 is reg- ulated by the circadian clock. Together, these data suggest that the phosphate transporter PHT4;1 is critical for basal defense and also implicate a potential role of the circadian clock in regulating innate immunity of Arabidopsis.

关键词： Biological clock disease resistance signal transduction Pseudomonas syringae phosphate transporter salicylic acid.

Unstructured kinetic models to simulate an arabinose switch that decouples cell growth from metabolite production

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Synthetic and Systems Biotechnology 2020年第3期5卷 222-229页

作者： Harley Edwards Peng Xu Department of Chemical Biochemical and Environmental EngineeringUniversity of Maryland Baltimore CountyBaltimoreMD21250USA

Modeling synthetic gene circuits to implement dynamic flux balancing is crucial in teaching and exploring metabolic engineering strategies to repartition metabolic precursors and construct efficient microbial cell *** fitness and production rates are often complex phenotypes that are governed by highly nonlinear,multivariable functions which are intrinsically linked through carbon *** solution of such dynamic system can be difficult for synthetic biologists to visualize or ***,researchers(Santala et al.,***.,2018)have implemented an arabinose based genetic switch to dynamically partition the central carbon flux between cell growth and product *** autonomous switch allowed dynamic shift from arabinose-associated cell growth to acetate-associated product(wax ester)*** system clearly demonstrates the effectiveness of using a genetic switch to decouple cell growth from product formation in a one-pot bioreactor to minimize operational *** with Michaelis-Menten kinetics,and Luedeking-Piret equations,we were able to reconstruct and analyze this metabolic switch in silica and achieved graphical solutions that qualitatively match with the experimental *** assessing physiologically-accessible parameter space,we observed a wide range of dynamic behavior and examined the different limiting *** solutions for this dynamic system can be viewed simultaneously and resolved in real time via buttons on the graphical user interface(GUI).Metabolic bottlenecks in the system can be accurately predicted by varying the respective rate *** GUI serves as a diagnosis toolkit to troubleshoot genetic circuits design constraints and as an interactive workflow of using this arabinose based genetic switch to dynamically control carbon flux,which may provide a valuable computational toolbox for metabolic engineers and synthetic biologists to simulate and understand complex genetic-metabol

关键词： Metabolic switches Biophysical models Dynamic control Metabolic engineering Central carbon flux Intelligent biomanufacturing Green chemistry

Photocurrent Studies of Ultraviolet Detector Based on Gallium Nitride Epilayer

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Chinese Physics Letters 1996年第11期13卷 874-877页

作者： YANG Kai QIN Lin-hong ZHANG Rong SHEN Bo ZHENG You-dou HUANG Zhen-chun JCChen Department of Physics Nanjing UniversityNanjing 210093 Department of Electrical Engineering University of Maryland Baltimore CountyBaltimoreMD 21228-5398USA

The properties of photoconductive blue and ultraviolet detector based on single crystal GaN epilayer grown on sapphire substrate by metalorganic chemical vapor deposition were *** observed optical absorption edge of 3.39eV in optical transmission has been confirmed by the peak of 3.400eV in *** detectable energy span of the GaN device up to ultraviolet was obtained by photocurrent *** dependence of the intensity of photocurrent on the chopper frequency in the measurement was studied,and an easy method was used to determine the response time as 0.4s.

关键词： measurement sapphire optical

Photoreflectance Study of GaN Films on Sapphire Substrate

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Chinese Physics Letters 1996年第2期13卷 153-156页

作者： QIN Lin-liong YANG Kai ZHENG You-clou ZHANG Rong DAI Xing-jiang FENG Duan HUANG Zhen-chun J.C.Chen Department of Physics Nanjing UniversityNanjing 210093 Department of Electrical Engineering University of Maryland Baltimore CountyBaltimoreMD 21228-5398USA

Photoreflectance was used to study the optical properties of single crystal hexagonal GaN finis on(0001)sapphire substrate grown by metalorganic chemical vapor *** energy gap of GaN was determined as 3.400 eV and the possible origin of the signal was *** absorption and reflection were *** optical absorption edge of 3.38 eV,and the reilectivity peak at 3.3 eV, confirmed the results of photoreiiectance.

关键词： GaN sapphire optical

A vibration-based structural damage detection method and its applications to engineering structures

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International Journal of Smart and Nano Materials 2011年第3期2卷 194-218页

作者： K.He W.D.Zhu Department of Mechanical Engineering University of MarylandBaltimore County1000 Hilltop CircleBaltimoreMD 21250USA

Two major challenges associated with avibration-based damage detection method using changes in natural frequencies are addressed:accurate modeling of structures and the development of a robust inverse algorithm to detect damage,which are defined as the forward and inverse problems,*** resolve the forward problem,new physics-based finite element modeling techniques are developed for fillets in thin-walled beams and for bolted joints,so that complex structures can be accurately modeled with a reasonable model *** resolve the inverse problem,a logistic function transformation is introduced to convert the constrained optimization problem to an unconstrained one,and a robust iterative algorithm using the Levenberg–Marquardt method is developed to accurately detect the locations and extent of *** new methodology can ensure global convergence of the iterative algorithm in solving under--determined system equations and deal with damage detection problems with relatively large modeling error and measurement *** is applied to various engineering structures including lightning masts,a space frame structure and one of its components,and a *** exact locations and extent of damage can be detected in the numerical simulation,and the locations and extent of damage can be successfully detected in experimental damage detection.

关键词： natural frequency forward problem inverse problem Levenberg-Marquardt method logistic function transformation

Socioeconomic Status and Obesity Gradient over Age： New Evidence from China

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2012年第1期7卷 70-93页

作者： Bing Ma Department of Economics University of Maryland Baltimore County Baltimore MD 21250USA

This paper presents a systematic analysis of the impact of socioeconomic status （SES） on overweight and obesity in China and investigates how and why the SES-obesity gradient differs with age. Using a longitudinal sample drawn from the China Health and Nutrition Survey （CHNS）, I find that body mass index （BMI） is positively associated with SES during early childhood but becomes inversely related to childhood SES as children age into adulthood. Estimation results show that children from low SES families are less likely to be overweight or obese than their median and high SES peers. The results from subsamples stratified by living area reveal that the SES gaps of obesity are generally larger for urban residents than rural residents. Females are significantly less likely to be overweight than males in China. The SES during childhood has independent effects after controlling for respondents＇ contemporaneous SES. The relationship between the contemporaneous SES of a male adult and his chance of being overweight or obese is significantly positive, while the contemporaneous SES of a female adult is negatively related to her chance of being overweight or obese.

关键词： body weight BMI overweight obesity socioeconomic status,China

An Overview of MODIS Radiometric Calibration and Characterization

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Advances in Atmospheric Sciences 2006年第1期23卷 69-79页

作者： Xiaoxiong XIONG William BARNES Earth Sciences Directorate NASA/Goddard Space Flight Center Greenbelt MD 20771 USA University of Maryland Baltimore County Baltimore MD 21250 USA

The Moderate Resolution Imaging Spectroradiometer （MODIS） is one of the key instruments for NASA＇s Earth Observing System （EOS）, currently operating on both the Terra and Aqua satellites. The MODIS is a major advance over the previous generation of sensors in terms of its spectral, spatial, and temporal resolutions. It has 36 spectral bands： 20 reflective solar bands （RSB） with center wavelengths from 0.41 to 2.1 μm and 16 thermal emissive bands （TEB） with center wavelengths from 3.7 to 14.4 μm, making observations at three spatial resolutions： 250 m （bands 1-2）, 500 m （bands 3-7）, and lkm （bands 8-36）. MODIS is a cross-track scanning radiometer with a wide field-of-view, providing a complete global coverage of the Earth in less than 2 days. Both Terra and Aqua MODIS went through extensive pre-launch calibration and characterization at various levels. In orbit, the calibration and characterization tasks are performed using its on-board calibrators （OBCs） that include a solar diffuser （SD） and a solar diffuser stability monitor （SDSM）, a v-grooved flat panel blackbody （BB）, and a spectro-radiometric calibration assembly （SRCA）. In this paper, we present an overview of MODIS calibration and characterization activities, methodologies, and lessons learned from pre-launch characterization and in-orbit operation. Key issues discussed in this paper include in-orbit efforts of monitoring the noise characteristics of the detectors, tracking the solar diffuser and optics degradations, and updating the sensor＇s response versus scan angle. The experiences and lessons learned through MODIS have played and will continue to play major roles in the design and characterization of future sensors.

关键词： EOS remote sensing Terra Aqua MODIS sensor calibration radiometry