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Camouflage Patterning in Maize Leaves Results from a Defect in Porphobilinogen Deaminase

Molecular Plant 2009年第4期2卷 773-789页

作者： Mingshu Huanga Thomas L. Slewinski R. Frank Baker , Diane Janick-Buckner brent Buckner Gurmukh S. Johal David M. Braun Department of Biology Pennsylvania State University University Park PA 16802 Division of Science Truman State University Kirksville MO 63501 Department of Botany and Plant Pathology Purdue University West Lafayette IN 47907

Maize leaves are produced from polarized cell divisions that result in clonal cell lineages arrayed along the long axis of the leaf. We utilized this stereotypical division pattern to identify a collection of mutants that form chloroplast pigmentation sectors that violate the clonal cell lineages. Here, we describe the camouflage1 （cfl） mutant, which develops nonclonal, yellow-green sectors in its leaves. We cloned the cfl gene by transposon tagging and determined that it encodes porphobilinogen deaminase （PBGD）, an enzyme that functions early in chlorophyll and heme biosynthesis. While PBGD has been characterized biochemically, no viable mutations in this gene have been reported in plants. To investigate the in vivo function of PBGD, we characterized the cfl mutant. Histological analyses revealed that cfl yellow sectors display the novel phenotype of bundle sheath cell-specific death. Light-shift experiments determined that constant light suppressed cfl sector formation, a dark/light transition is required to induce yellow sectors, and that sectors form only during a limited time of leaf development. Biochemical experiments determined that of 1 mutant leaves have decreased PBGD activity and increased levels of the enzyme substrate in both green and yellow regions. Furthermore, the cfl yellow regions displayed a reduction in catalase activity. A threshold model is hypothesized to explain the cfl variegation and incorporates photosynthetic cell differentiation, reactive oxygen species scavenging, and PBGD function.

关键词： camouflage1 maize porphobilinogen deaminase tetrapyrrole biosynthesis variegated leaf.

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塔里木盆地跃参地区YJ1X井超深层油藏演化

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石油勘探与开发 2022年第2期49卷 262-273页

作者：杨鹏刘可禹 LI Zhen MCINNES brent Ian Alexander 刘建良中国石油大学(华东)深层油气重点实验室山东青岛266580 海洋国家实验室海洋矿产资源评价与探测技术功能实验室山东青岛266071 John de Laeter Centre Faculty of Science and EngineeringCurtin UniversityPerth WA 6485Australia

基于原位方解石U-Pb定年、原油与储集岩烃类地球化学特征对比以及流体包裹体分析,恢复塔里木盆地塔北隆起西南部跃参地区YJ1X井奥陶系一间房组超深层油藏的充注与演化过程。研究结果表明:①原油、游离油以及包裹体油具有相似的地球化学... 详细信息

基于原位方解石U-Pb定年、原油与储集岩烃类地球化学特征对比以及流体包裹体分析,恢复塔里木盆地塔北隆起西南部跃参地区YJ1X井奥陶系一间房组超深层油藏的充注与演化过程。研究结果表明:①原油、游离油以及包裹体油具有相似的地球化学特征,其对应的烃源岩在相同的沉积环境中形成;②原油、游离油以及包裹体油具有相似的成熟度,计算得到的等效镜质体反射率值为0.80%~0.96%;③储集层中识别出两种不同类型的油包裹体组合,其中Ⅰ类代表充注过程中最初进入圈闭、气体相对饱和的原油,Ⅱ类代表油藏发生轻微轻烃泄漏后残留的欠饱和原油;④该油藏在距今约425 Ma的早泥盆世发生过1期油充注,尽管在中泥盆世发生过部分轻烃泄漏,但之后一直保存完好。该研究表明在盖层发育良好、构造相对稳定的含油气盆地超深层中存在潜在的古老油气藏,可为下步的超深层油气勘探提供借鉴。

关键词：油藏保存方解石U-Pb定年流体包裹体奥陶系超深层碳酸盐岩油藏塔里木盆地

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Photonic radio frequency channelizers based on Kerr optical micro-combs

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Journal of Semiconductors 2021年第4期42卷 17-32页

作者： Mengxi Tan Xingyuan Xu Jiayang Wu Thach G.Nguyen Sai T.Chu brent E.Little Roberto Morandotti Arnan Mitchell David J.Moss Optical Sciences Centre Swinburne University of TechnologyHawthornVIC 3122Australia Electro-Photonics Laboratory Department of Electrical and Computer Systems EngineeringMonash UniversityVIC3800Australia School of Engineering RMIT UniversityMelbourneVIC 3001Australia Department of Physics City University of Hong KongHong KongChina State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of ScienceXi'an 710119China INRS-Énergie Matériaux et Télécommunications1650 Boulevard Lionel-BouletVarennesQuébecJ3X 1S2Canada Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

We review recent work on broadband RF channelizers based on integrated optical frequency Kerr micro-combs combined with passive micro-ring resonator filters,with microcombs having channel spacings of 200 and 49 *** approach to realizing RF channelizers offers reduced complexity,size,and potential cost for a wide range of applications to microwave signal detection.

关键词： microwave photonic signal channelization integrated optical frequency comb

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The iPhone on Training Wheels For Steve Jobs and his touchy-feely telephone,it's been a bumpy ride

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国际经济合作 2007年第12期 1-1页

作者： brent Schlender

Nearly five months have passed since Steve Jobs unleashed his flashy i-Phone upon the world,and the sleek,do-everything gadget has met his ambi-tious initial sales targets and then some-so far,more than 1.5

关键词： iPhone 音乐手机苹果公司创新

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Orthogonally polarized RF optical single sideband generation with integrated ring resonators

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Journal of Semiconductors 2021年第4期42卷 53-66页

作者： Mengxi Tan Xingyuan Xu Jiayang Wu Thach G.Nguyen Sai T.Chu brent E.Little Arnan Mitchell Roberto Morandotti David J.Moss Optical Sciences Centre Swinburne University of TechnologyHawthornVIC 3122Australia Electro-Photonics Laboratory Department of Electrical and Computer Systems EngineeringMonash UniversityVIC3800Australia School of Engineering RMIT UniversityMelbourneVIC 3001Australia Department of Physics City University of Hong KongHong KongChina State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of ScienceXi'an 710119China INRS-Énergie Matériaux et Télécommunications1650 Boulevard Lionel-BouletVarennesQuébecJ3X 1S2Canada Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

We review recent work on narrowband orthogonally polarized optical RF single sideband generators as well as dualchannel equalization,both based on high-Q integrated ring *** devices operate in the optical telecommunications C-band and enable RF operation over a range of either fixed or thermally tuneable *** operate via TE/TM mode birefringence in the *** achieve a very large dynamic tuning range of over 55 dB for both the optical carrier-to-sideband ratio and the dual-channel RF equalization for both the fixed and tunable devices.

关键词： microwave photonics micro-ring resonators radio frequency

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Long-distance ranging with high precision using a soliton microcomb

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Photonics Research 2020年第12期8卷 1964-1972页

作者： JINDONG WANG ZHIZHOU LU WEIQIANG WANG FUMIN ZHANG JIAWEI CHEN YANG WANG JIHUI ZHENG SAI T.CHU WEI ZHAO brent E.LITTLE XINGHUA QU WENFU ZHANG State Key Laboratory of Precision Measuring Technology&Instruments Tianjin UniversityTianjin 300072China State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Department of Physics and Materials Science City University of Hong KongHong KongChina

Laser-based light detection and ranging(lidar)plays a significant role in both scientific and industrial ***,it is difficult for existing lidars to achieve high speed,high precision,and long distance ***,we demonstrate a high-performance lidar based on a chip-scaled soliton microcomb(SMC)that can realize all three specialties *** by the excellent properties of ultrahigh repetition rate and the smooth envelope of the SMC,traditional optical frequency comb(OFC)-based dispersive interferometry is heavily improved and the measuring dead zone induced by the mismatch between the repetition rate of the OFC and resolution of the optical spectrum analyzer is totally *** with an auxiliary dual-frequency phase-modulated laser range finder,the none-dead-zone measurable range ambiguity is extended up to 1500 *** proposed SMC lidar is experimentally implemented in both indoor and outdoor *** the outdoor baseline field,real-time,high-speed(up to 35 k Hz)measurement of a long distance of^1179 m is achieved with a minimum Allan deviation of 5.6μm at an average time of 0.2 ms(27 nm at an average time of 1.8 s after high-pass filtering).The present SMC lidar approaches a compact,fast,high-precision,and none-dead zone long-distance ranging system,aimed at emerging applications of frontier basic scientific research and advances in industrial manufacturing.

关键词： lidar soliton high

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The Effects of 5 Weeks of Leg-Drive Training on Bench Press Performance in Recreationally-Trained,College-Age Men

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Journal of Science in Sport and Exercise 2022年第3期4卷 231-236页

作者： Jacob K.Gardner Justin T.Chia brent M.Peterson Kelsey L.Miller Department of Kinesiology and Health Science Biola University13800 Biola AveLa MiradaCA 90639USA Department of Health and Human Development Western Washington University516 High StreetBellinghamWA 98225USA

Introduction The bench press is commonly used to measure upper-body *** much emphasis has been placed on the upper-body,little is known about how the lower-body can play a role in bench press ***-drive is a technique that includes flexing the knee so the feet line up posterior to the knee joint,while simultaneously contracting the knee extensors isometrically during the *** purpose of this study was to compare strength characteristics of lifters in a standard bench press versus a leg-drive bench press over the course of 5-weeks of *** Twenty-three recreationally active males(age:22.4±2.1 years,height:175.0±5.9 cm,mass:78.4±9.5 kg)were randomized into a standard bench or leg-drive bench press *** performed four sets to failure,two times per week for five *** of interests were training volume and 1-repetition maximum(1RM)*** training volume,a 2×5(group×week)repeated measures analysis of variance(RMANOVA)was *** the 1RM’s,a 2×2×2(group×press type×time)RMANOVA was used.A priori alpha levels were set to *** Over time,both groups showed an approximate 6%increase in 1RM *** volume for week 4 was 5.6%less than week 5,but was not different from weeks 1 through *** between-group differences were observed for 1RM strength or training *** This results of this work indicates that 5 weeks of leg-drive training is effective in increasing 1RM strength,but was not more effective than standard bench press ***,lifters should choose either lifting style based on personal preference.

关键词： Chest press Lower-body Weight lifting Isometric contraction

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Thyroid Hormone and Brain Development

Thyroid Hormone and Brain Development

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中华医学会第十三次全国内分泌学学术会议

作者： Gregory A.brent Departments of Medicine and Physiology David Geffen School of Medicine at UCLALos AngelesCAUSA

Thyroid hormone is essential for normal brain development,as well as brain function in the *** hormone acts on all brain areas,with well-described actions on the cortex and cerebellum,as well as the pituitary and sensory development of the retina and inner *** defects in sensory processing seen in children,appropriately diagnosed and treated for congenital hypothyroidism

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个体的专门化、集体的适应和环境变化的速度

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心理发展与教育 1991年第3期7卷 29-33页

作者： Sandor.B.brent 申继亮美国韦恩州立大学心理系

在高级有机体发展史和低级有机体发展史之间存在着一种复杂的辩证关系。这种辩证关系对于我们理解遗传与环境的关系和“代沟”问题都会有所启发,所以探讨这一问题对当代发展心理学有着重要意义。一。

关键词：有机体环境条件发展过程发展心理学代沟专门化相互关系环境变化模式成年人

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Image guidance in endoscopic sinus surgery and skull base surgery

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中华临床医师杂志（电子版） 2012年第12期6卷 1-7页

作者： Mitchell R.Gore brent A.Senior Mitchell R.Gore Brent A.Senior University of North Carolina at Chapel Hill Department of Otolaryngology Head and Neck SurgeryUNC Chapel HillCB#7070Chapel HillNC 27514 Mitchell R.Gore Brent A.Senior University of North Carolina at Chapel Hill Department of Otolaryngology Department of OtolaryngologyUNC Chapel HillCB#7070Chapel HillNC 27514

Objective The objective of this study was to review the current clinical applications and impact of intraoperative imaging on endoscopic sinonasal and skull base procedures in adult and pediatric *** The PubMed database was searched for articles related to the use of image guidance in otolaryngology using the search terms "image guidance otolaryngology".This was supplemented by the authors′ experience utilizing image guidance in nearly 3000 endoscopic sinus and skull base *** The literature demonstrates that intraoperative image guidance has utility in primary and revision endoscopic sinus surgery,as well as endoscopic surgery of the skull *** guidance also has applications in pediatric endoscopic surgery,such as pediatric sinus surgery and repair of choanal *** Intraoperative image guidance,when combined with a thorough knowledge of paranasal sinus and skull base anatomy and technical proficiency,can provide improved safety when performing otolaryngologic procedures from endoscopic sinus surgery to endoscopic skull base *** not a substitute for knowledge of anatomy,the increased availability and usability of image guidance systems make them a useful tool in the armamentarium of the otolaryngologist/head and neck surgeon and neurosurgeon.

关键词：耳鼻喉科内窥镜鼻窦临床分析

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