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Nano Research 2009年第6期2卷 500-508页

作者： Aaron m.mohs Hongwei Duan Brad A.Kairdolf andrew m.smith Shuming Nie Departments of Biomedical Engineering and Chemistry Emory University and Georgia Institute of Technology101 Woodruff Circle NESuite 2001AtlantaGeorgia 30322USA

Semiconductor quantum dots(QDs)have shown great promise as fluorescent probes for molecular,cellular and in vivo ***,the fluorescence of traditional polymer-encapsulated QDs is often quenched by proton-induced etching in acidic *** is a major problem for applications of QDs in the gastrointestinal tract because the gastric(stomach)environment is strongly acidic(pH 12).Here we report the use of proton-resistant surface coatings to stabilize QD fl uorescence under acidic *** both hyperbranched polyethylenimine(PEI)and its polyethylene glycol derivative(PEG-grafted PEI),we show that the fl uorescence of coreshell CdSe/CdS/ZnS QDs is effectively protected from quenching in simulated gastric *** comparison,amphiphilic lipid or polymer coatings provide no protection under similarly acidic *** proton-resistant QDs are found to cause moderate membrane damage to cultured epithelial cells,but PEGylation(PEG grafting)can be used to reduce cellular toxicity and to improve nanoparticle stability.

关键词： Nanoparticle quantum dot oral delivery gastrointestinal polyethylenimine(PEI) polyethylene glycol(PEG)

A New Generation of Semiconductor Quantum Dots for molecular and Cellular Imaging

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A New Generation of Semiconductor Quantum Dots for Molecular...

A New Generation of Semiconductor Quantum Dots for molecular and Cellular Imaging

第十一次中国生物物理学术大会暨第九届全国会员代表大会

作者： andrew m.smith mary Wen Departments of Biomedical Engineering and Chemistry Emory University

＜正＞Semiconductor quantum dots,tiny light-emitting particles on the nanometer scale,are emerging as a new class of fluorescent labels for a broad range of molecular and cellular

关键词： Quantum Dot fluorescent label molecular imaging

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生物物理学报 2009年第S1期25卷 161-161页

作者： andrew m.smith mary Wen Departments of Biomedical Engineering and Chemistry Emory University 101 Woodruff Circle Suite 2001AtlantaGA30322USA

Semiconductor quantum dots, tiny light-emitting particles on the nanometer scale, are emerging as a new class of fluorescent labels for a broad range of molecular and

关键词： Quantum Dot fluorescent label molecular imaging

利用聚合物多齿配体紧密包覆量子点的高效生物偶联

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利用聚合物多齿配体紧密包覆量子点的高效生物偶联

microstructure segmentation with deep learning encoders pre-trained on a large microscopy dataset

中国化学会第30届学术年会-第三十一分会：胶体与界面化学

作者：屠春来马亮 andrew m.smith 上海科技大学物质科学与技术学院美国伊利诺伊大学厄巴纳-香槟分校

通过合理设计的配位单体和亲水链单体的活性无规共聚合成的线性聚合物多齿配体,能够利用OH离子剥除量子点表面烷基链配体,再进行配体交换的方法,紧密包覆在具有核壳结构的CdSe/CdZnS量子点表面,制备得到单分散的均相水溶液体系,并且能... 详细信息

通过合理设计的配位单体和亲水链单体的活性无规共聚合成的线性聚合物多齿配体,能够利用OH离子剥除量子点表面烷基链配体,再进行配体交换的方法,紧密包覆在具有核壳结构的CdSe/CdZnS量子点表面,制备得到单分散的均相水溶液体系,并且能够减小量子点的水动力学尺寸,增强量子点的胶体稳定性和提高量子效率。表面功能改性的量子点能够进一步与生物大分子进行高效偶联,可用于生物靶向成像和单分子动态成像。

关键词：聚合物多齿配体粒子表面改性单分散生物偶联生物成像

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npj Computational materials 2022年第1期8卷 1905-1916页

作者： Joshua Stuckner Bryan Harder Timothy m.smith materials and Structures Division NASA Glenn Research Center21000 Brookpark RdClevelandOH44135USA

This study examined the improvement of microscopy segmentation intersection over union accuracy by transfer learning from a large dataset of microscopy images called *** neural network encoder architectures were trained on over 100,000 labeled microscopy images from 54 material *** pre-trained encoders were then embedded into multiple segmentation architectures including UNet and DeepLabV3+to evaluate segmentation performance on created benchmark microscopy *** to ImageNet pre-training,models pre-trained on microNet generalized better to out-of-distribution micrographs taken under different imaging and sample conditions and were more accurate with less training *** training with only a single Ni-superalloy image,pre-training on microNet produced a 72.2%reduction in relative intersection over union *** results suggest that transfer learning from large in-domain datasets generate models with learned feature representations that are more useful for downstream tasks and will likely improve any microscopy image analysis technique that can leverage pre-trained encoders.

关键词： union intersection image

Strigolactones redefine plant hormones

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Science China(Life Sciences) 2016年第10期59卷 1083-1085页

作者： Lu Wang Steven m.smith School of Biological Sciences University of Tasmania Institute of Genetics and Developmental Biology Chinese Academy of sciences

A commonly accepted view of plant growth hormones is that their interaction with the cognate receptor protein is reversible, so that each hormone molecule can potentially interact multiple times with a receptor and so either amplify the hormone signal or maintain it over an extended period of time. The signal can be ＇cancelled＇ by degrading the hormone. Strigolactones present us with a potentially new paradigm. The receptor is a serine hydrolase-type protein which attacks the strigolactone resulting in covalent modi- fication of the receptor, while at the same time destroying the hormone. Strigolactone is apparently a one-use ＇dispos- able＇ hormone.

关键词：植物激素受体蛋白定义植物生长激素相互作用激素信号酸水解

Acetylation as a mechanism that regulates axonal regeneration

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Neural Regeneration Research 2015年第7期10卷 1034-1036页

作者： Shen Lin George m.smith Shriners Hospitals for Pediatric Research Center Department of Neuroscience Temple University

The capacity for adult axons to regenerate after injury is diminished compared with developing *** the case of central nervous system（CNS）axons,injury causes a total failure to *** failure is due to both the intrins... 详细信息

关键词： gene HDAC Acetylation as a mechanism that regulates axonal regeneration

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David B.smith Steven m.smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

Breeding high-yield superior quality hybrid super rice by rational design

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National Science Review 2016年第3期3卷 283-294页

作者： Qian Qian Longbiao Guo Steven m.smith Jiayang Li State Key Laboratory for Rice Biology China National Rice Research InstituteChinese Academy of Agricultural Sciences State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of Genetics and Developmental BiologyChinese Academy of Sciences Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural Sciences School of Biological Sciences University of Tasmania

The challenge of meeting the increasing demand for worldwide rice production has driven a sustained quest for advances in rice breeding for yield. Two breakthroughs that led to quantum leaps in productivity last century were the introduction of semidwarf varieties and of hybrid rice. Subsequent gains in yield have been incremental. The next major leap in rice breeding is now upon us through the application of rational design to create defined ideotypes. The exploitation of wide-cross compatibility and intersubspecific heterosis,combined with rapid genome sequencing and the molecular identification of genes for major yield and quality traits have now unlocked the potential for rational design.

关键词： Oryza sativa L super rice hybrids molecular breeding grain yield grain quality

Reactive astrocyte scar and axon regeneration:suppressor or facilitator?

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Neural Regeneration Research 2016年第7期11卷 1050-1051页

作者： Yosuke Ohtake George m.smith Shuxin Li Shriners Hospitals Pediatric Research Center Department of Anatomy and Cell BiologyDepartment of NeuroscienceLewis Katz School of Medicine at Temple University

Several major factors are known to contribute to CNS axon regenerative failure after injury, including reduced intrinsic growth capacity of developed neurons and extrinsic factors mediating axon outgrowth. For the latter, a non-permissive environment around the lesion and the lack of sufficient neurotrophic support within the adult CNS play important roles （Silver et al., 2015）. In addition to generation of various inhibitory substrates by oligodendrocytes, fibrotic tissues, inflammatory cells and other cell types, reactive astrocytes surrounding lesions are thought to highly suppress regeneration of injured CNS axons （Silver and miller, 2004; Ohtake and Li, 2014）. A great number of studies suggest that reactive astrocytic scars form one of the major barriers preventing axon regeneration after CNS iniuries, including spinal cord injury （SCI）. However, reactive astrocytes were reported to provide a beneficial role by reducing infiltrating immunoreactive cells into adjacent domains, protecting bordering neural tissue from damage and generating numerous supportive extracellular matrix （ECm） components to promote cell survival and growth （Bush et al., 1999）. Previ- ous data showed that ablation of reactive astrocytes increased inflammation and secondary tissue damage, prevented blood- brain barrier formation and increased local neurite growth. Interestingly, a recent study by Anderson et al （2016） provides evidence that reactive astrocytes around the lesioned spinal cord support axon regeneration after SCI, rather than block regrowth （Anderson et al., 2016）.

关键词： astrocyte regeneration suppressor neurotrophic extrinsic latter intrinsic glial injured sensory