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Journal of Forestry Research 2018年第5期29卷 1365-1377页

作者： R.W.James Dennis Jay R.malcolm sandy m.smith m.Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks St.Toronto ON M5S 3B3 Canada Departamento de Ecología Genética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and IEGEBA (CONICET)Buenos Aires Argentina

Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest *** used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central *** clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was *** consistently emerged more from Populus than from Picea dead *** of the studied saproxylic families were more abundant in late-decay than in early-decay *** of the Cecidomyiidae,Ceratopogonidae,Empididae,mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead *** contrast,mymaridae was most abundant in standing dead *** study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.

关键词： Boreal forest Dead wood quality Forest harvesting High-level taxa Saproxylic insects

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

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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

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

Automated SNP Genotype Clustering Algorithm to Improve Data Completeness in High-Throughput SNP Genotyping Datasets from Custom Arrays

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Genomics, Proteomics & Bioinformatics 2007年第3期5卷 256-259页

作者： Edward m.smith Jack Littrell michael Olivier Human and molecular Genetics Center Medical College of WisconsinMilwaukeeWI 53226USA.

High-throughput SNP genotyping platforms use automated genotype calling algorithms to assign genotypes. While these algorithms work efficiently for individual platforms, they are not compatible with other platforms, and have individual biases that result in missed genotype calls. Here we present data on the use of a second complementary SNP genotype clustering algorithm. The algorithm was originally designed for individual fluorescent SNP genotyping assays, and has been optimized to permit the clustering of large datasets generated from custom-designed Affymetrix SNP panels. In an analysis of data from a 3K array genotyped on 1,560 samples, the additional analysis increased the overall number of genotypes by over 45,000, significantly improving the completeness of the experimental data. This analysis suggests that the use of multiple genotype calling algorithms may be advisable in high-throughput SNP genotyping experiments. The software is written in Perl and is available from the corresponding author.

关键词： clustering SNP genotyping algorithm

A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China

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Journal of Rock mechanics and Geotechnical Engineering 2024年第7期16卷 2388-2410页

作者： Yibing Ning Huiming Tang Jianbing Peng Yanjun Shen John V.smith Bocheng Zhang College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China Academy of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of Engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in *** slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole *** stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled ***,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected *** toppled rock blocks mainly suffer sliding failures beyond the layer symmetry *** factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling Evolutionary process Reservoir impoundment Rock slope

Bilateral nephrolithiasis and upper tract transitional cell carcinoma in horseshoe kidney

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Current Urology 2024年第3期18卷 247-249页

作者： Jacob m.Gaines Eric J.macdonald Arun Rai David Hoenig Arthur smith Zeph Okeke Tareq Aro The smith Institute for Urology Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellLake SuccessNYUSA

Nephroureterectomy is currently the criterion-standard treatment for high-grade upper tract urothelial carcinoma(UTUC).Current guidelines and expert opinions propose some exceptions to this approach based on patient characteristics,disease status,and function of the contralateral *** present a rare case of a patient with horseshoe kidney,bilateral large nephrolithiasis,high-grade UTUC in one moiety,and relative parenchymal thinning of the contralateral *** patient was treated with a percutaneous,minimally invasive,nephron sparing *** patient also had intracollecting system instillations of gemcitabine and *** invasive percutaneous resection of high-grade UTUC is a safe procedure in select *** guidelines may not apply to all patients;unique scenarios with UTUC may require personalized decision-making and treatment at specialized centers.

关键词： Upper tract urothelial cancer Percutaneous resection Horseshoe kidney Nephrolithiasis

Proton-Resistant Quantum Dots: Stability in Gastrointestinal Fluids and Implications for Oral Delivery of Nanoparticle Agents

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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)