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ANTI-PLANE ANALYSIS FOR ELLIPTICAL INCLUSION IN MAGNETOELECTROELASTIC MATERIALS

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Acta Mechanica Solida Sinica 2009年第2期22卷 137-142页

作者： Gang Li Baolin Wang Jiecai hart Shanyi Du Graduate School at Shenzhen Harbin Institute of Technology Harbin 150001 China

This paper considers the multi-field coupling in magneroelectroelastic composite materials consisting of the inclusion and the matrix are magnetoelectroelastic materials. The mechanical,electric and magnetic fields around an elliptical cylinder inclusion are formulated by complex potentials. Inside the inclusion,the strain,electric and magnetic fields are found to be uniform and vary with the shape of the ellipse. When the inclusion is reduced to a crack,along the interface,the strain,electric field strength and magnetic field strength equal the corresponding remote ones,which can be used as the boundary condition. Special cases,such as a rigid and permeable inclusion,a soft and impermeable inclusion,a line inclusion and a crack problem are discussed in detail.

关键词： fracture mechanics magnetoelectroelastic composites crack inclusion

High-throughput quantification of microbial birth and death dynamics using fluorescence microscopy

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Frontiers of Electrical and Electronic Engineering in China 2019年第1期7卷 69-81页

作者： Samuel F. M. hart david Skelding Adam J. Waite Justin C. Burton Wenying Shou Fred Hutchinson Cancer Research Center SeattleWA 98109USA

Background: Microbes live in dynamic environments where nutrient concentrations fluctuate. Quantifying fitness in terms of birth rate and death rate in a wide range of environments is critical for understanding microbial evolution and ecology. Methods^ Here, using high-throughput time-lapse microscopy, we have quantified how Saccharomyces cerevisiae mutants incapable of synthesizing an essential metabolite (auxotrophs) grow or die in various concentrations of the required metabolite. We establish that cells normally expressing fluorescent proteins lose fluorescence upon death and that the total fluorescence in an imaging frame is proportional to the number of live cells even when cells form multiple layers. We validate our microscopy approach of measuring birth and death rates using flow cytometry, cell counting, and chemostat culturing. Results: For lysine-requiring cells, very low concentrations of lysine are not detectably consumed and do not support cell birth, but delay the onset of death phase and reduce the death rate compared to no lysine. In contrast, in low hypoxanthine, hypoxanthine-requiring cells can produce new cells, yet also die faster than in the absence of hypoxanthine. For both strains, birth rates under various metabolite concentrations are better described by the sigmoidal-shaped Moser model than the well-known Monod model, while death rates can vary with metabolite concentration and time. Conclusions: Our work reveals how time-lapse microscopy can be used to discover non-intuitive microbial birth and death dynamics and to quantify growth rates in many environments.

关键词： Saccharomyces cerevisiae fluorescence microscopy microbial growth birth rate death rate

Synthesis of cobalt, palladium, and rhenium nanoparticles

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Tungsten 2020年第3期2卷 261-288页

作者： Shahab Ranjbar Bahadori Ryan hart Yao‑Wu Hao Department of Materials Science and Engineering University of Texas at ArlingtonArlingtonTX 76019USA

Over the past decade,metal nanoparticles(MNPs)have attracted extensive attention due to their unique physiochemical properties that make them highly applicable in various fields such as chemical sensing,energy storage,catalysis,medicine,and environmental *** physiochemical properties depend drastically on the MNP size and morphology,which are largely determined by their synthesis *** on MNPs predominantly focused on coinage metals(Au,Ag and Cu),but in the last decade research on metals with a relatively high melting temperature such as Pd,Co,and Re has seen rapid increases,mainly driven by their potential applications as *** paper presents the recent advances on different synthesis techniques of Co,Pd,and Re nanoparticles,their resulting nanostructures,as well as existing and potential applications.

关键词： Nanotechnology Co nanoparticle Pd nanoparticle Re nanoparticle Nanoparticle synthesis

Biomarkers of Aging: An Overview

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Biomedical and Environmental Sciences 1991年第1期4卷 130-133页

作者： ANGELO TURTURRO RONALD W.hart National Center for Toxicological Research JeffersonNational Center for Toxicological Research Jefferson Akansas 72079Akansas 72079

INTRODUCTION Although aging has often been thought of as some intrinsic, immutable process, an alternative is to approach aging as a toxic endpoint resulting from a combination of endogenous and exogenous damage. Aging is then defined as consisting of a combination of functional declines observed in every organism system, occurring at different ages for different systems (Shock, 1985). One measure of this decline is death, and mortality is often used as a surrogate for aging. The sources of endogenous

关键词： Biomarkers of Aging An Overview

根据加拿大中部花粉记录定量重建植被演变历史的研究

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中国科学（D辑） 2008年第11期38卷 1396-1403页

作者：于革 hart Catherine Mary Vetter david Sauchyn 湖泊与环境国家重点实验室中国科学院南京地理与湖泊研究所南京210008 Prairie Adaptation Research Collaborative SKS4S 7J7Canada Department of Biology University of ReginaS4S 0A2Canada Department of Geography University of ReginaS4S 0A2Canada

根据加拿大中部高精度湖泊钻孔的花粉数据,介绍花粉型组合生态系植被单元和现代类比法模拟古植被的研究方法,报告拟合现代植被和验证生态系区后应用在沉积花粉中、重建过去1000年以来古植被的主要结果.该研究表明,在115°～95°W和40°... 详细信息

根据加拿大中部高精度湖泊钻孔的花粉数据,介绍花粉型组合生态系植被单元和现代类比法模拟古植被的研究方法,报告拟合现代植被和验证生态系区后应用在沉积花粉中、重建过去1000年以来古植被的主要结果.该研究表明,在115°～95°W和40°～60°N的北美中部,花粉模拟的现代植被中的北方林型最佳类比率81%,稀树草地型72%,草原和稀树草地型94%,与北美Ⅱ生态系植被分布基本吻合.钻孔沉积花粉的植被模拟反映了过去1000年北美中部经历了中世纪暖期,具有温暖而干旱的气候;小冰期前期寒冷而湿润,后期寒冷而干旱;20世纪具有显著的增温和转干特征.该项研究可为中国学者采用花粉记录探索过去1000年以来植被变化,尤其是在具有特征气候区域、10～100年时间精度的气候植被研究提供良好的研究途径和科学依据.

关键词：沉积花粉表土花粉现代类比法生态系区古植被过去1000年

The Effects of Dispersed Phase Morphology Induced by Flow on the Bulk Viscosity of HDPE/PA Blends

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Chinese Chemical Letters 2006年第11期17卷 1515-1518页

作者： Hong Mei YANG Zhen Wei ZHANG hart LI Qiang ZHENG Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Zhejiang University Hangzhou 310027

The apparent shear viscosity （ηα） of a blend composed of 97 wt % high-density polyethylene （HDPE） and 3 wt % polyamide （PA-66） was measured by capillary rheometry at different shear rates, below, near and above the melting point of PA-66, i.e. 240℃, 260℃ and 280℃, respectively. At 260℃ and a high shear rate, ηα of the blend reduced abnormally; and at 260℃, was lower than that at 280℃. The images of etched surface of extrudate observed by the SEM showed different dispersed phase morphology, induced by flow at different temperatures. It is suggested that the formation of fibrillar morphology of dispersed phase is a key factor for the abnormal reduction of ηα for the HDPE/PA blend.

关键词： Viscosity reduction polyethylene polyamide droplet deformation.

Molecular mechanisms of metastasis in prostate cancer

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Asian Journal of Andrology 2009年第1期11卷 57-67页

作者： Noel W. Clarke Claire A. hart Mick D. Brown Genito-Urinary Cancer Research Group School of Cancer and lmaging Sciences Paterson Institute for Cancer ResearchChristie Hospital University of Manchester Manchester M20 4BX UK

Prostate cancer （PCa） preferentially metastasizes to the bone marrow stroma of the axial skeleton. This activity is the principal cause of PCa morbidity and mortality. The exact mechanism of PCa metastasis is currently unknown, although considerable progress has been made in determining the key players in this process. In this review, we present the current understanding of the molecular processes driving PCa metastasis to the bone.

关键词： bone bone marrow stroma metastasis prostate cancer

Machine-learned multi-system surrogate models for materials prediction

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npj Computational Materials 2019年第1期5卷 702-707页

作者： Chandramouli Nyshadham Matthias Rupp Brayden Bekker Alexander V.Shapeev Tim Mueller Conrad W.Rosenbrock Gábor Csányi david W.Wingate Gus L.W.hart Department of Physics and Astronomy Brigham Young UniversityProvoUT 84602USA Fritz Haber Institute of the Max Planck Society Faradayweg 4–614195 BerlinGermany Skolkovo Institute of Science and Technology Skolkovo Innovation CenterBuilding 3Moscow 143026Russia Department of Materials Science and Engineering Johns Hopkins UniversityBaltimoreMD 21218USA Engineering Laboratory University of CambridgeTrumpington StreetCambridge CB21PZUK Computer Science Department Brigham Young UniversityProvoUT 84602USA Citrine Informatics 702 Marshall StreetRedwood CityCA 94063USA

Surrogate machine-learning models are transforming computational materials science by predicting properties of materials with the accuracy of ab initio methods at a fraction of the computational *** demonstrate surrogate models that simultaneously interpolate energies of different materials on a dataset of 10 binary alloys(AgCu,AlFe,AlMg,AlNi,AlTi,CoNi,CuFe,CuNi,FeV,and NbNi)with 10 different species and all possible fcc,bcc,and hcp structures up to eight atoms in the unit cell,15,950 structures in *** find that the deviation of prediction errors when increasing the number of simultaneously modeled alloys is<1 meV/*** state-of-the-art materials representations and learning algorithms were found to qualitatively agree on the prediction errors of formation enthalpy with relative errors of<2.5% for all systems.

关键词： alloys prediction CoNi

CD74 is a survival receptor on colon epithelial cells

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World Journal of Gastroenterology 2010年第26期16卷 3258-3266页

作者： Nitsan Maharshak Sivan Cohen Frida Lantner Gili hart Richard Bucala Idit Shachar Department of Immunology Weizmann Institute of Science Rehovot 76100 Israel Department of Gastroenterology and Liver Diseases Tel Aviv Sourasky Medical Center Affiliated to the Sackler Faculty of Medicine Tel Aviv University Tel Aviv 69978 Israel Department of Medicine Yale University School of Medicine New Haven CT 06520 United States

AIM: To investigate the expression and function of CD74 in normal murine colon epithelial cells (CEC) and colon carcinoma cells. METHODS: Expression of CD74 mRNA and protein were measured by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and fluorescence-activated cell sorter (FACS). The effect of migration inhibitory factor (MIF) on the survival of normal CEC from C57BL/6, NOD/SCID, and CD74 def icient mice both in vitro and in vivo, and on the CT26 carcinoma cell line was analyzed by (quantitative) qRT-PCR, RTPCR, Western blotting and FACS. RESULTS: CD74 was found to be expressed on normalCEC. Stimulation of CD74 by MIF induced a signaling cascade leading to up-regulation of Bcl-2 expression, resulting in a signif icant increased survival of CEC. CD74 was also expressed on the CT26 colon carcinoma cell line and its stimulation by MIF resulted in enhanced cell survival, up-regulation of Akt phosphorylation and Bcl-2 expression.

关键词： CD74 Migration inhibitory factor Colon epithelial cells