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Two decades of compositional and structural change in deciduous old-growth forests of Indiana,USA

Journal of Plant Ecology 2016年第3期9卷 256-271页

作者： Christy A.Lowney Bradley D.Graham Martin A.Spetich Stephen R.Shifley michael R.Saunders michael a.jenkins Department of Forestry and Natural Resources and Hardwood Tree Improvement and Regeneration Center Purdue University715 West State StreetWest Lafayette IN 47907USA Arkansas Forestry Sciences Laboratory USDA Forest ServiceSouthern Research StationP.O.Box 1270Hot SpringsAR 71902USA USDA Forest Service Northern Research Station202 ABNR BuildingColumbiaMO 65201USA

Aims Using a network of permanent plots,we determined how multiple old-growth forests changed over an 18-19-year period at a state-wide *** examination of change allowed us to assess how the compositional and structural stability of each forest varied with site characteristics(topography,physiography and productivity)and stochastic *** In 2011,we resampled 150 plots distributed across five old-growth hardwood forests in Indiana,USA that were originally sampled in *** each plot,we relocated and remeasured the diameter at breast height(dbh)of all trees(≥10.0 cm)present during the 1992-1993 sample,which allowed us to track their individual fates through time for growth and mortality *** that grew to≥10.0 cm dbh since plot establishment were designated as *** dbh and species of all saplings(stems≥2.0 cm but<10.0 cm dbh)were also *** each forest,we calculated density(stems ha^(−1)),basal area(BABA;m^(2)ha^(−1))and importance value(relative density+relative BABA)/2 of trees by *** saplings,density per ha was calculated by species for each *** also calculated annual mortality rate(AMR)for three diameter classes(10-29.9,30-59.9 and≥60 cm)and species richness(S),evenness(E)and Shannon-Weiner diversity(H')for the tree and sapling *** between years were compared for each forest using paired t-tests and Wilcoxon signed rank *** FindingsAlthough we observed commonality in changes across some sites,our results suggest that these forests differ in their rates and trajectories of *** in total stand BABA and density varied across sites and were influenced by past disturbance and mortality *** observed a general increase in the overstory dominance of Acer saccharum coupled with a general decrease in the dominance of Quercus section Lobatae(red oak group)*** of overstory trees present in 1992-1993 ranged from 27%to 49%over the study period(mean AM

关键词： forest remnants forest structure long-term data mortality species diversity stand development.

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Innovative approaches to genome editing in avian species

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Journal of Animal Science and Biotechnology 2018年第2期9卷 278-284页

作者： Caitlin A.Cooper Timothy J.Doran Arjun Challagulla Mark L.V.Tizard Kristie a.jenkins CSIRO Health and Biosecurity Australian Animal Health Laboratory

The tools available for genome engineering have significantly improved over the last 5 years, allowing scientist to make precise edits to the genome. Along with the development of these new genome editing tools has come advancements in technologies used to deliver them. In mammals genome engineering tools are typically delivered into in vitro fertilized single cell embryos which are subsequently cultured and then implanted into a recipient *** avian species this is not possible, so other methods have been developed for genome engineering in birds. The most common involves in vitro culturing of primordial germ cells(PGCs), which are cells that migrate through the embryonic circulatory system to the developing gonad and colonize the gonad, eventually differentiating into the gonadocytes which produce either sperm or ova. While in culture the PGCs can be modified to carry novel transgenes or gene edits, the population can be screened and enriched, and then transferred into a recipient embryo. The largest drawback of PGC culture is that culture methods do not transfer well across avian species, thus there are reliable culture methods for only a few species including the chicken. Two newer technologies that appear to be more easily adapted in a wider range of avian species are direct injection and sperm transfection assisted gene editing(STAGE).The direct injection method involves injecting genome engineering tools into the circulatory system of the developing embryo just prior to the developmental time point when the PGCs are migrating to the gonads. The genome engineering tools are complexed with transfection reagents, allowing for in vivo transfection of the PGCs. STAGE utilizes sperm transfection to deliver genome engineering tools directly to the newly fertilized embryo. Preliminary evidence indicates that both methodologies have the potential to be adapted for use in birds species other than the chicken, however further work is needed in this area.

关键词： Avian CRISPR Genome engineering PGCs Sperm TALEN

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A boronic acid-based fluorescent hydrogel for monosaccharide detection

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 112-116页

作者： Suying Xu Adam C.Sedgwick Souad A.Elfeky Wenbo Chen Ashley S.Jones George T.Williams A.Toby a.jenkins Steven D.Bull John S.Fossey Tony D.James Department of Biochemistry Faculty of ScienceBeijing University of Chemical TechnologyBeijing 100029China Department of Chemistry University of BathBath BA27AYUK Department of Chemistry University of Texas at AustinTX 78712-1224USA School of Chemistry University of BirminghamBirmingham B152TTUK National Institute of Laser Enhanced Sciences Cairo UniversityGiza 12613Egypt Higher Institute for Optics Technology SheratonCairo 17361Egypt Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China

A boronic acid-based anthracene fluorescent probe was functionalised with an acrylamide unit to incorporate into a hydrogel system for monosaccharide *** solution,the fluorescent probe displayed a strong fluorescence turn-on response upon exposure to fructose,and an expected trend in apparent binding constants,as judged by a fluorescence response where D-fructose>D-galactose>D-mannose>*** hydrogel incorporating the boronic acid monomer demonstrated the ability to detect monosaccharides by fluorescence with the same overall trend as the monomer in solution with the addition of D-fructose resulting in a 10-fold enhancement(≤0.25 mol/L).

关键词： boron hydrogel monomer

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Electrophysiological assessment of primary cortical neurons genetically engineered using iron oxide nanoparticles

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Nano Research 2017年第8期10卷 2881-2890页

作者： michael G. Evans Arwa Al-Shakli Stuart I. jenkins Divya M. Chari School of Life Sciences Keele University Keele Staffordshire ST5 5BG UK Institute for Science and Technology in Medicine Keele University Keele Staffordshire ST5 5BG UK

The development of safe technologies to genetically modify neurons is of great interest in regenerative neurology, for both translational and basic science applications. Such approaches have conventionally been heavily reliant on viral transduction methods, which have safety and production limitations. Magnetofection （magnet-assisted gene transfer using iron oxide nanoparticles as vectors） has emerged as a highly promising non-viral alternative for safe and reproducible genetic modification of neurons. Despite the high potential of this technology, there is an important gap in our knowledge of the safety of this approach, namely, whether it alters neuronal function in adverse ways, such as by altering neuronal excitability and signaling. We have investigated the effects of magnetofection in primary cortical neurons by examining neuronal excitability using the whole cell patch clamp technique. We found no evidence that magnetofection alters the voltage-dependent sodium and potassium ionic currents that underpin excitability. Our study provides important new data supporting magnetofection as a safe technology for bioengineering of neuronal cell populations.

关键词： transfection magnetic nanoparticle green fluorescent protein (GFP) whole-cell patch clamp fluorescence microscopy

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Harnessing piggyBac Transposon for cancer gene discovery in Zebrafish

Harnessing piggyBac Transposon for cancer gene discovery in ...

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2010·第一届斑马鱼学术研讨会

作者： Sergey Parinov Alexander Emelyanov Nancy a.jenkins Neal G.Copeland Temasek Life Sciences laboratory

Transposon-based insertional mutagenesis offers enormous potential for systematically identifying the genes that cause developmental defects and various *** such screens have recently been developed in mice,their cost...

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Interaction of the Arabidopsis UV-B-Specific Signaling Component UVR8 with Chromatin

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Molecular Plant 2008年第1期1卷 118-128页

作者： Catherine Cloix Gareth I. jenkins Plant Science Group Division of Biochemistry and Molecular Biology Institute of Biomedical and Life Sciences Bower Building University of GlasgowGlasgow G12 BQQ UK

Arabidopsis UV RESISTANCE LOCUS8 （UVR8） is a UV-B-specific signaling component that regulates expression of a range of genes concerned with UV protection. Here, we investigate the interaction of UVR8 with chromatin. Using antibodies specific to UVR8 in chromatin immunoprecipitation （ChiP） assays with wild-type plants, we show that native UVR8 binds to chromatin in vivo. Similar experiments using an anti-GFP antibody with plants expressing a GFP-UVR8 fusion show that UVR8 associates with a relatively small region of chromatin containing the HY5 gene. UVR8 interacts with chromatin containing the promoter regions of other genes, but not with all the genes it regulates. UV-B is not required for the interaction of UVR8 with chromatin because association with several gene loci is observed in the absence of UV-B. Pulldown assays demonstrate that UVR8 associates with histones in vivo and competition experiments indicate that the interaction is preferentially with histone H2B. ChIP experiments using antibodies that recognize specific histone modifications indicate that the UV-B-stimulated transcription of some genes may be correlated with histone modification. In particular, the ELIP1 promoter showed a significant enrichment of diacetyl histone H3 （K9/K14） following UV-B exposure. These findings increase understanding of the interaction of the key UV-B-specific regulator UVR8 with chromatin.

关键词： UV RESISTANCE LOCUS8 (UVR8) chromatin immunoprecipitation (ChIP)

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A Review of CDER's Novel Drug Approvals for 2016

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Journal of Chinese Pharmaceutical Sciences 2017年第2期26卷 161-162页

作者： John jenkins Office of New Drugs in FDA’s Center for Drug Evaluation and Research

This past year was another successful year for the new drugs program in FDA＇s Center for Drug Evaluation and Research （CDER）. CDER reviewed and approved 22 novel drugs, most of which have the potential to add signi... 详细信息

关键词：期刊编辑工作中国药学会议信息

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Dredging effects on selected nutrient concentrations and ecoenzymatic activity in two drainage ditch sediments in the lower Mississippi River Valley

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International Soil and Water Conservation Research 2017年第3期5卷 190-195页

作者： Matt Moore Martin A.Locke michael jenkins Robert W.Steinriede Daniel S.McChesney USDA-Agricultural Research Service National Sedimentation Laboratory598 McElroy DriveOxfordMS 38655USA

Agricultural drainage ditches are conduits between production acreage and receiving aquatic *** overlooked for their mitigation capabilities,agricultural drainage ditches provide an important role for nutrient transformation via microbial *** in ecoenzyme activities have been used to elucidate microbial metabolism and resource demand of microbial communities to better understand the relationship between altered nutrient ratios and microbial activity in aquatic *** agricultural drainage ditches,one in the northeast portion of the Arkansas Delta and the other in the lower Mississippi Delta,were monitored for a *** samples were collected prior to each ditch being dredged(cleaned),and subsequent post-dredging samples occurred as soon as access was *** samples were then collected throughout a year to examine effects of dredging on selected nutrient concentrations and ecoenzymatic activity recovery in drainage ditch *** concentrations in sediments after dredging decreased 33–66%,depending on ditch and phosphorus extraction ***,ecoenzymatic activity was significantly decreased in most sediment samples after *** diacetate hydrolysis activity,an estimate of total microbial activity,decreased 56–67%after dredging in one of the two *** sample sites also had significant phosphorus and ecoenzymatic activity differences between the post-dredge samples and the year-long follow-up *** indicate microbial metabolism in dredged drainage ditches may take up to a year or more to recover to pre-dredged ***,while sediment nutrient concentrations may be decreased through dredging and removal,runoff and erosion events over time tend to quickly replenish nutrient concentrations in replaced *** nutrient dynamics and microbial metabolism within agricultural drainage ditches is a crucial step toward addressing issues of nutri

关键词： Phosphorus FDA Denitrification Mehlich III Microbial Metabolism

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Methodology of Single Crystal Growth and Microstructure Analysis of CoTi(Zr) Intermetallic Compounds

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Journal of Materials Science & Technology 2005年第6期21卷 817-821页

作者： Mike L.jenkins Glyn TAYLOR Department of Materials University of Oxford Parks Road Oxford OX1 3PH UK

The effects of preparation and crystal growth methods on the microstructure, composition, and oxidation of CoTi（Zr） intermetallics were dealt with . A group of methods has been used to produce CoTi and CoTi（Zr） crystals to prevent the formation of titanium oxide particles during melting and crystal growth. The results show that more oxides formed when using powdered starting materials even though the metals handled were and melted under an inert gas atmosphere; using bulk starting materials produced alloys showed less oxidation than powders, but adding a small amount of AI to getter the oxygen was not sufficient to prevent TiO2 formation. However, using a slightly reducing atmosphere during initial melting was highly effective in reducing the formation of oxide. Crystal growth carried out in Ar did not reduce the amount of oxide but only redistributed the particles. TiO2 particles were found only in the grain boundaries after crystal growing, where they obstructed grain growth. Crystal growth in a vacuum was found to be essential in producing oxide free crystals. A seed selection technique was developed and used in growing CoTi single crystals. The microstructures of the samples were determined using optical microscopy, scanning electron microscopy and transmission electron microscopy, including the morphologies, grain sizes, oxide distributions and crystal structure confirmation.

关键词： CoTi CoTi(Zr) Intermetallics Crystal growth Nicrostructure

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与环境烟气相关的挥发性有机物的特性

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中国烟草学报 2000年第1期6卷 7-18页

作者： Sung-Ok Baek Roger a.jenkins 韩国岭南大学环境工程系美国橡树岭国家实验室

本项研究测定了环境烟气 (ETS)中的多种挥发性有机物 ,在环境实验室中目标化合物的唯一来源就是ETS。实验室中的ETS是由燃吸肯塔基参考卷烟和其他 8种市售卷烟产生的。在 12轮试验中同时测定了 3 0多种化合物。目标化合物分为 3类 ,即 ... 详细信息

本项研究测定了环境烟气 (ETS)中的多种挥发性有机物 ,在环境实验室中目标化合物的唯一来源就是ETS。实验室中的ETS是由燃吸肯塔基参考卷烟和其他 8种市售卷烟产生的。在 12轮试验中同时测定了 3 0多种化合物。目标化合物分为 3类 ,即 :气相ETS标识物 3 乙基吡啶 (简称 3 EP)与烟碱、羰基化合物 (包括甲醛 )和挥发性有机化合物 (简称VOCs)。利用环境实验室研究结果可以确定各种VOCs与 3 EP(气相ETS标记物 )的特征比率 ,另外还可以用来估测与ETS相关的VOCs的散发因子。总体说来 ,本项研究测得的特征比率与以往已经发表的实验室研究数据是一致的 ,这意味着 ,“真实”室内环境受多种来源的复杂的混合物影响。

关键词：环境烟气挥发性有机物特征比值烟碱 3-乙基吡啶苯室内环境空气

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