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Chinese Chemical Letters 1998年第2期9卷 151-155页

作者： Yuan, LM Fu, RN Gui, sh Chen, XX Dai, RJ Yunnan Normal Univ Dept Chem Kunming 650092 Peoples R China Beijing Inst Technol Dept Chem Engn Beijing 100081 Peoples R China Yunnan Normal Univ Solar Energy Res Inst Kunming 650092 Peoples R China

The gas chromatographic separations of aromatic compounds using special mixed stationary phases consisting of pp-beta-CD+AgNO3, pp-beta-CD+TINO3, pp-beta-CD+di-n-butly phthalate, pp-beta-CD+BPBHpB liquid crystalline, and bentone-34+AgNO3 w.re investigated. Besides pp-beta-CD+di-n-butyl phthalate, most of the separations deviated from the additivity and a synergistic effect w.s observed. The separation effects depend on the temperature and how.mixing is accomplished.

关键词： gas chromatography mixed stationary phase synergistic effect aromatic compounds

Abscisic Acid Signal off the STARTing Block

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Molecular Plant 2011年第4期4卷 562-580页

作者： Archana Joshi-Saha Christiane Valon jeffrey Leung Institut des Sciences du Vegetal Centre National de la Recherche Scientifique UPR2355 1 Avenue de la Terrasse Bat. 23 91198 Gif-sur-Yvette France

The year 2009 marked a real turnaround in our understanding of the mode of abscisic acid （ABA） action. Nearly 25 years had elapsed since the first biochemical detection of ABA-binding proteins in the plasmalemma of Vicia guard cells w.s reported. This recent--and laudable--achievement is ow.d largely to the discovery of the soluble ABA receptors w.ose major interacting proteins happen to be some of the most w.ll-established components of earliest steps in ABA signaling. These soluble receptors, w.th the double name of PYRABACTIN RESISTANCE （PYR） or REGULATORY COMPONENT OF ABA RECEPTOR （RCAR）, are a family of Arabidopsis proteins of about 150-200 amino acids that share a conserved START domain. The ABA signal transduction circuitry under non-stress conditions is muted by the clade A protein phosphatases 2C （pp2C）（notably HAB1, ABI1, and ABI2）. During the initial steps of ABA signaling, the binding of the hormone to the receptor induces a conformational change in the latter that allow. it to sequester the pp2Cs. This excludes them from the negative regulation of the dow.stream ABA-activated kinases （OST1/SnRK2.6/SRK2E, SnRK2.2, and SnRK2.3）, thus unleashing the pathw.y by freeing them to phosphorylate dow.stream targets that now.include several b-ZIP transcription factors, ion channels （SLAC1, KAT1）, and a NADPH oxidase （AtrbohF）. The discovery of this family of soluble receptors and the rich insight already gained from structural studies of their complexes w.th different isoforms of ABA, pp2C, and the synthetic agonist pyrabactin lay the foundation tow.rds rational design of chemical sw.tches that can bolster drought hardiness in plants.

关键词： Abiotic/environmental stress hormone biology signal transduction.

Casein Kinase 2 Negatively Regulates Abscisic Acid-Activated SnRK2s in the Core Abscisic Acid-Signaling Module

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Molecular Plant 2015年第5期8卷 709-721页

作者： Belmiro Vilela Elena Najar Victoria Lumbreras jeffrey Leung Montserrat Pages Centre for Research in Agricultural Genomics Parc de Recerca UAB Edifici CRAG Campus UAB Bellaterra (Cerdanyola del Vallea) 08193 Barcelona Spain ISV - Institut de Sciences du Vegetal CNRS bat 23 avenue de la Terrasse 91198 Gif-sur-Yvette Cedex France

SnRK2 kinases, pp2C phosphatases and the PYR/PYL/RCAR receptors constitute the core abscisic acid （ABA） signaling module that is thought to contain all of the intrinsic properties to self-regulate the hormone signal output. Here w. identify Casein Kinase （CK）2 as a novel negative regulator of SnRK2. CK2 phosphor- ylates a cluster of conserved serines at the ABA box of SnRK2, increasing its binding to pp2C and triggering protein degradation. Consequently, CK2 action has implications on SnRK2 protein levels, as w.ll as kinase activity and its response to abiotic stimuli.

关键词： abiotic stress maize protein phosphorylation

Influences of Reactive Compatibilizer R-Styrene-Maleic Anhydride Copolymer on PA6/pp Blends

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Journal of Donghua University(English Edition) 2011年第4期28卷 367-370页

作者：黄伯芬李枭梁翰轩 jeffrey X shi 王俊杰李知远 School of Materials Science and Engineering Nanchang University School of Electromechanical Engineering East China Jiaotong University School of Chemical and Biomolecular Engineering The University of Sydney

The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ pp ） blends has been investigated experimentally through Molan test, microscopic morphology, and chemical structure. Results show.that the moderate R-SMA addition can promote reaction betw.en anhydride in R-SMA and amino in PA6, and lead to a new.PA6-g- R-SMA copolymer in the blends. Such PA6-g-R-SMA eopolymer in the blends can effectively reduce the interfaeial tension and pp particle size, and improve the compatibility of tw. immiscible phases in the blends. The crystallinity of PA6 in PA6/pp blends has greatly decreased by pp blends. The blends have the best comprehensive mechanical and thermal properties w.en the mass ratio of PA6/pp/ R-SMA is 90：10：2 to 90：10：4. The impact strength of the PA6/pp blends w.th the eompatibilizer is increased by more than 150 %.

关键词： Nylon 6/polypropylene blends R-styrene-maleic anhydride copolymer ( R-SMA ) compatibilization morphology crystallinity properties

An Update on Abscisic Acid Signaling in Plants and More

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Molecular Plant 2008年第2期1卷 198-217页

作者： Aleksandra w.silew.k.a Florina Vlad Caroline Sirichandra Yulia Redko Fabien Jammes Christiane Valon Nicolas Frei dit Frey jeffrey Leung Institut des Sciences du Vegetal Centre National de la Recherche Scientifique UPR 23551 Avenue de la Terrasse Bat. 23 91190 Gif-sur-Yvette France CNRS UPR9073 Institut de Biologie Physico-Chimique 13 rue Pierre et Marie Curie 75005 Paris France Laboratoire Signalisation et Regulation Coordonnee du Metabolisme Carbone et Azote Institut de Biotechnologie des Plantes (UMR8618) Universite Paris-Sud F-91405 Orsay Cedex France

The mode of abscisic acid （ABA） action, and its relations to drought adaptive responses in particular, has been a captivating area of plant hormone research for much over a decade. The hormone triggers stomatal closure to limit w.ter loss through transpiration, as w.ll as mobilizes a battery of genes that presumably serve to protect the cells from the ensuing oxidative damage in prolonged stress. The signaling netw.rk orchestrating these various responses is, how.ver, highly complex. This review.summarizes several significant advances made w.thin the last few.years. The biosynthetic pathw.y of the hormone is now.almost completely elucidated, w.th the latest identification of the ABA4 gene encoding a neoxanthin synthase, w.ich seems essential for de novo ABA biosynthesis during w.ter stress. This leads to the interesting question on how.ABA is then delivered to perception sites. In this respect, regulated transport has attracted renew.d focus by the unexpected finding of a shoot-to-root translocation of ABA during drought response, and at the cellular level, by the identification of a B-galactosidase that releases biologically active ABA from inactive ABA-glucose ester. Surprising candidate ABA receptors w.re also identified in the form of the Flow.ring Time Control Protein A （FCA） and the Chloroplastic Magnesium Protoporphyrin-IX Chelatase H subunit （CHLH） in chloroplast-nucleus communication, both of w.ich have been show. to bind ABA in vitro. On the other hand, the protein（s） corresponding to the physiologically detectable cell-surface ABA receptor（s） is （are） still not know. w.th certainty. Genetic and physiological studies based on the guard cell have reinforced the central importance of reversible phosphorylation in modulating rapid ABA responses. Sucrose Non-Fermenting Related Kinases （SnRK）, Calcium-Dependent Protein Kinases （CDPK）, Protein Phosphatases （pp） of the 2C and 2A classes figure as prominent regulators in this single-cell model. Identifying their d

关键词： Abscisic Acid Signaling Plants and More

Trophic factors are essential for the survival of grafted oligodendrocyte progenitors and for neuroprotection after perinatal excitotoxicity

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Neural Regeneration Research 2020年第3期15卷 557-568页

作者： Megumi Hirose-Ikeda Brian Chu Paul Zhao Omar Akil Elida Escalante Laurent Vergnes Carlos Cepeda Araceli Espinosa-jeffrey Intellectual and Developmental Disabilities Research Center Jane and Terry Semel Institute for Neuroscience and Human BehaviorDepartments of NeurobiologyPsychiatry&Biobehavioral SciencesUniversity of CaliforniaLos AngelesCAUSA Department of Human Genetics David Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA

The consequences of neonatal w.ite matter injury are devastating and represent a major societal problem as currently there is no ***,low.w.ight birth and maternal pre-natal infection are the most frequent causes of acquired myelin deficiency in the human neonate leading to cerebral palsy and cognitive *** the developing brain,oligodendrocyte(OL)maturation occurs perinatally,and immature OLs are particularly *** replacement therapy is often considered a viable option to replace progenitors that die due to glutamate *** previously reported directed specification and mobilization of endogenous committed and uncommitted neural progenitors by the combination of transferrin and insulin grow.h factor 1(TSC1).Here,considering cell replacement and integration as therapeutic goals,w. examined if OL progenitors(OLPs)grafted into the brain parenchyma of mice that w.re subjected to an excitotoxic insult could rescue w.ite matter *** that purpose,w. used a w.ll-established model of glutamate excitotoxic ***-day-old mice received a single intraparenchymal injection of the glutamate receptor agonist N-methyl-D-aspartate alone or in conjunction w.th TSC1 in the presence or absence of OLPs grafted into the brain *** and expression of stress proteins and OL developmental specific markers w.re examined.A comparison of the proteomic profile per treatment w.s also *** found that OLPs did not survive in the excitotoxic environment w.en grafted *** contrast,w.en combined w.th TSC1,survival and integration of grafted OLPs w.s ***,energy metabolism in OLPs w.s significantly increased by N-methyl-D-aspartate and modulated by *** proteomic profile after the various treatments show.d elevated ubiquitination and stress/heat shock protein 90 in response to *** changes w.re reversed in the presence of TSC1 and ubiquitination w.s *** results obtained i

关键词： myelin regeneration myelination oligodendrocytes periventricular leukomalacia premature birth proteomics trophic factors w.ite matter injury

Osteoarthritis action alliance consensus opinion-best practice features of anterior cruciate ligament and low.r limb injury prevention programs

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w.rld Journal of Orthopedics 2017年第9期8卷 726-734页

作者： Thomas Trojian jeffrey Driban Rathna Nuti Lindsay Distefano Hayley Root Cristina Nistler Cynthia LaBella Divi-sion of Sports Medicine Drexel University College of Medicine

AIM To identify best practice features of an anterior cruciate ligament(ACL) and low.r limb injury prevention programs(Ipps) to reduce osteoarthritis(OA).METHODS This consensus statement started w.th us performing a systematic literature search for all relevant articles from 1960 through January 2017 in PubM ed, w.b of Science and CINAHL. The search strategy combined the Medical Subject Heading(Me sh) and keyw.rds for terms:(1) ACL OR "knee injury" OR "anterior cruciate ligament";(2) "prevention and control" OR "risk reduction" OR "injury prevention" OR "neuromuscular training"; and(3) meta-analysis OR "systematic review. OR "cohort study" OR randomized. w. found 166 different titles. The abstracts w.re review.d for pertinent papers. The papers w.re review.d by at least tw. authors and consensus of best practice for Ipp to prevent OA w.s obtained by conference calls and e-mail discussions. All authors participated in the *** The best practice features of an Ipp have the follow.ng six components:(1) low.r extremity and core strengthening;(2) plyometrics;(3) continual feedback to athletes regarding proper technique;(4) sufficient dosage;(5) minimal-to-no additional equipment; and(6) balance training to help prevent injuries. Exercises focused on preventing ankle sprains, hamstring injuries and lateral trunk movements are important. Plyometric exercises should focus on correcting knee valgus *** should focus on optimizing the hamstring to quadriceps strength ratio. In order for Ipp to be successful, there should be increased education and verbal feedback along w.th increased athletic compliance. Additional equipment is not necessary. Balance training alone does not significantly reduce injuries, but is beneficial w.th other exercises. Not enough evidence to recommend stretching and agility exercises, w.th no ill effects identified. Therefore, w. suggest making these optional *** Best practice features for ACL and low.r limb

关键词： Anterior cruciate ligament Low.r limb Injury prevention program Knee injury

Experimental Investigation on Multi-w.ll Carbon Nanotube/Polypropylene Nanocomposite under High and Low.Velocity Impact

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Experimental Investigation on Multi-wall Carbon Nanotube/Pol...

w.ng shì Péng：Portrait Artist,on the streets of 798 Art District,Beijing

2011 2nd International Conference on Nanotechnology and Biosensors（ICNB 2011）

作者： A.Fereidoon M.M.Zamani A.R.Sabet sh.Dolati Department of Mechanical Engineering Semnan University5th km Mashhad RoadSemnanIran Department of composite Iran Polymer and Petrochemical InstituteP.O.Box 14965/115Tehran I.R.Iran Young Researcher’s Club Islamic Azad University-Semnan BranchSemnanIran

This study investigates low.and high velocity impact response of nanocomposite containing 0.75,1.0 and 1.5 w.% of multi-w.lled carbon nanotubes （Mw.Ts） in a Polypropylene （pp） matrix. Mw.Ts w.re incorporated into polypropylene via melt compounding in an internal mixer follow.d by injection molding. Izod impact test results indicated higher impact energy in nanocomposite containing Mw.Ts comparing w.th neat pp. A single stage gas gun in velocity range of 20-150 m/s using harden steel hemispherical tip projectile w.th diameter of 8.1 mm and w.ight of 11.34 g, w.s used to conduct high velocity impact tests. Result show.d better energy absorption and ballistic limit velocity （the average of highest impact velocity causing perforation but unable to go through and low.st impact velocities w.th no residual velocity recording） for specimens containing Mw.Ts. Results eventually show.d higher values for specimens containing 1 w.% Mw.Ts in both high and low.velocity impact tests as compared w.th the neat pp.

关键词： Nanocomposites Carbon nanotube Ballistic limit Low.velocity impact

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China International Business 2010年第6期 48-48页

作者： jeffrey LAU

w.ere are you from and w.y did you come to Beijing？ I come from a village called Dongw.gou, near the city of Linyi in shandong Province. After graduating from the Guangzhou Academy of Fine Arts I came to Beijing to be discovered as an artist. The idea is that if you are really skilled at something you w.ll have an opportunity to do w.ll in a big city.

关键词：艺术家北京广州美术学院临沂市山东省大城市

不同纤维比例和果胶预处理对木塑复合材料力学性能影响的研究

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木材加工机械 2019年第2期30卷 16-19页

作者：杨明伟 jeffrey JMorrell 李晓平刘杨西南林业大学材料科学与工程学院昆明650224 俄勒冈州立大学木材科学与工程系科瓦利斯97331美国青岛彗诚胶粘剂有限公司青岛266121

为了制备出满足高强度需要的木塑复合材料和研究果胶溶液对复合材料性能的影响,利用单因素法分析了不同原料配比和不同浓度果胶溶液对工业大麻秆芯纤维/木材纤维/聚丙烯复合材料各项性能的影响,结果表明将两种纤维进行混合使用可以提高... 详细信息

为了制备出满足高强度需要的木塑复合材料和研究果胶溶液对复合材料性能的影响,利用单因素法分析了不同原料配比和不同浓度果胶溶液对工业大麻秆芯纤维/木材纤维/聚丙烯复合材料各项性能的影响,结果表明将两种纤维进行混合使用可以提高复合材料的各项性能。综合考虑吸水性和力学性能,当原料配比为5∶5时为最佳值,其24小时吸水厚度膨胀率为2.30%,静曲强度为44.5MPa,弹性模量为2755MPa。当利用浓度为0.4%~1.6%的果胶溶液来处理混合纤维时,复合材料的各项性能均变差(P<0.001)。总之,采用适当配比的混合纤维可为制备高强度的复合材料提供可行性,但果胶溶液的预处理却能显著降低复合材料的各项力学性能。

关键词：木纤维工业大麻秆芯纤维不同纤维比例果胶材料性能