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    题名 作者 年代 出处 被引量
1浙闽沿海地区I型-A型复合花岗岩体的地球化学及成因显示文摘以鼓山-魁岐、青田和普陀山-桃花岛三个典型岩体为例,系统研究了浙闽沿海I型-A型复合花岗岩体的地质和地球化学特征。研究结果表明:复合岩体中I型与A型花岗岩在主量、微量和稀土元素特征上均存在明显变异。总体而言,A型花岗岩较之I型花岗岩富硅、富碱、贫钙、镁、铝,并具偏高的Rb/Sr、Rb/Ba、Ga/Al和偏低的LREE/HREE比值及显著的铕负异常。两类花岗岩的Nd、Sr同位素组成均具有壳幔混熔岩浆的特点,但仍存在一定的变异。上述变异既有岩浆分异演化的影响,又有幔源岩浆卷入的贡献,在不同的复合岩体中起主导作用的因素各不相同。通过对岩石产出动力地质背景的全面分析,结合本区不同复合岩体中二类花岗岩具不同地球化学变异特点的地质事实,提出浙闽沿海I型-A型复合花岗岩是区域构造应力、断裂构造。邱检生 王德滋 Brent I.A.McInnes 1999岩石学报1999,15,2:83
2国外旅游扶贫研究进展显示文摘在相关概念辨析的基础上,对国外旅游扶贫理论、实践模式、效果、研究方法、相关国际组织的作用进行了综述。国外旅游扶贫形成了较为系统的理论体系与研究框架,为旅游实践提供了理论支持。从研究内容看,自然旅游、遗产旅游、农业旅游、社区旅游是旅游扶贫的主要方式;从扶贫效果看,旅游扶贫对当地经济有较大的促进作用,但需要合理的规划与操控才能可持续。旅游扶贫研究方法以宏观的定量研究为主,研究案例呈现地理集中性。今后应加强城市贫困问题、精准旅游扶贫及中国旅游扶贫案例的研究。李会琴 侯林春 杨树旺 J R Brent Ritchie 2015人文地理2015,30,1:147
3川东北地区构造-热演化探讨--来自(U-Th)/He年龄和Ro的约束显示文摘利用镜质组反射率和磷灰石与锆石的(U-Th)/He年龄一起模拟了川东北地区三叠纪以来的构造-热演化特征。结果表明早三叠世的热流值在51~66mW/m2,自晚三叠世至白垩纪随盆地性质由前陆盆地演化为陆内坳陷盆地,热流缓慢降低直至现今的44.5mW/m2。但在晚白垩世—古新世时期受燕山晚期构造运动的影响,热流有一个微弱增高的现象。同时,磷灰石和锆石的He年龄揭示了川东北地区大致在晚白垩世期间开始隆升且抬升剥蚀量较大。因此,磷灰石和锆石的(U-Th)/He年龄可以揭示后期详细的冷却历史。邱楠生 秦建中 Brent I A Mclnnes 王杰 腾格尔 郑伦举 2008高校地质学报2008,14,2:59
4普渡大学本科工程教育改革实践及对新工科建设的启示显示文摘如何迎接第四次工业革命对工程教育的挑战,是中国工程教育发展无法回避的问题,向欧美等发达国家学习和借鉴成功经验是一条有效途径。本研究选择美国传统工科名校普渡大学为案例,通过实地考察、深度访谈、资料查阅等方式,系统研究其在专业培养标准制定、培养方案制定与实施、新专业设置、课程体系建设、教学方式方法转变等方面的改革实践和成功经验,并结合我国实际情况提出相应思考和建议,以期对新工科建设有一定的启发作用。林健 彭林 Brent Jesiek 2019高等工程教育研究2019,67,1:56
5线粒体控制区在鱼类种内遗传分化中的意义显示文摘线粒体DNA(mtDNA)作为分子标记已被广泛应用于各物种系统发生的研究。mtDNA控制区序列(D-loop)以其较高的突变积累对于研究物种种内的遗传分化具有重要价值。鱼类是脊椎动物中最原始但在种属数量上又最占优势的类群,其物种繁多,分布广泛,起源复杂,研究其系统发生历来是令人饶有兴趣的课题。D-loop在研究鱼类种内遗传分化中具有多方面的重要意义。近年来,已有越来越多的研究工作将D-loop作为分子标记来探讨各种鱼类的种内遗传分化,并且获得了许多有启发性的结果。青海湖是我国内陆最大的咸水湖,湖中主要鱼类为青海湖裸鲤(Gymnocypris przewalskii),D-loop分析初步结果显示青海湖及其周围河流中的裸鲤似乎没有新的种内遗传分化现象。谢振宇 杜继曾 陈学群 WANG Yu-Xiang Brent W Murray 2006遗传2006,28,3:28
6普渡大学跨学科工程教育案例及对新工科建设的启示显示文摘如何在现有院系结构基础上,打破传统学科分类界限形成跨学科人才培养机制是关乎新工科建设成败的大事。本研究通过深度访谈等方式,对美国普渡大学跨学科工程教育体系进行系统研究:①项目制跨越院系边界,形成跨学科工程教育体系。基于大类培养的FYE夯实了通识教育基础;工程教育系成为跨学科工程教育实验室与孵化器;需求端导向的项目是整个体系的骨架。②通过EPICS联合社区服务机构培养学生跨学科工程实践能力。项目采用垂直整合的管理模式;跨学科特色贯穿EPICS的5个阶段;项目需求驱动了EPICS课程设置。③通过CAPSTONE'真刀真枪'锻炼高年级学生跨学科工程设计能力。CAPSTONE是企业真实需求导向,重视工程设计过程与跨学科的课程,形成了校企协同育人机制。研究最后对新工科建设及跨学科工程教育提出相应建议。彭林 林健 Brent Jesiek 2019高等工程教育研究2019,0,6:13
7(U-Th)/He技术约束下库车盆地北缘构造热演化——以吐孜2井为例显示文摘库车前陆盆地蕴藏着丰富的油气资源,然而盆地中新生代的构造热演化史一直缺乏有效的研究,制约了油气的勘探.本文测试了吐孜2井磷灰石、锆石(U-Th)/He年龄数据,建立了He年龄随现今温度/深度变化的关系,确定该区磷灰石(U-Th)/He体系封闭温度为89℃.综合利用(U-Th)/He及镜质体反射率(Ro)数据模拟恢复了库车盆地吐孜2井中新生代热演化史,结果表明库车盆地吐孜洛克背斜形成起始时间约为5Ma,新生代抬升剥蚀量平均约为670m,平均抬升剥蚀速率为0.133mm/a.根据新生代吐孜洛克背斜的构造演化分析确定了气源断裂活动及圈闭形成的时期,揭示了吐孜洛克背斜天然气成藏时间为5Ma以后,且烃源岩生排烃、断裂活动及圈闭形成的时间具有良好的匹配关系,这是吐孜洛克油气田形成的关键因素之一.本文应用(U-Th)/He技术研究沉积盆地构造热演化史,对库车盆地油气勘探具有重要的意义.喻顺 陈文 吕修祥 Noreen Evans Brent McInnes 尹继元 孙敬博 李洁 2014地球物理学报2014,57,1:13
8反演南方海相层系热史动态演化的新温标——磷灰石、锆石(U-Th)/He年龄和封闭温度显示文摘对川东北普光一毛坝地区和通江地区的11个岩心和露头样品进行锆石、磷灰石(u—Th)/He定年分析,初步建立了He年龄一深度/温度动态演化模式,该地区磷灰石He封闭温度为85℃。川东北钻井岩心和剖面样品经历相同的热演化历程。该地区第三纪至第四纪为冷却抬升剥蚀主要时期,剥蚀速率约为74.8~172.5m/Ma,剥蚀厚度大约为2800~3000m,地温逐渐降低到磷灰石He封闭温度,直至达到现今温度,与青藏高原隆升引发的新构造运动在四川盆地的响应有关。普光5井等3200m以上中生界样品未经历过锆石He封闭温度,可能只有3200m以下的样品经历锆石He封闭温度,但所有样品都经历了磷灰石He封闭温度。根据锆石(U—Th)/He年龄大致推算出,川东北地区可能在晚侏罗世开始抬升,在晚侏罗世一早白垩世期间普光一毛坝地区和通江地区都处于缓慢抬升剥蚀阶段,只是普光一毛坝地区抬升剥蚀开始时间要早于通江地区。磷灰石和锆石He封闭温度和年龄揭示了该区动态热演化历史。该区在178.0Ma之前古地温大于170~1900C,随后地层继续抬升,古地温下降;在40.5~178.0Ma时,古地温为85—170℃;在0~40.5Ma时,现今地温小于85℃。秦建中 王杰 邱楠生 Brent McInnes 陶成 2010石油与天然气地质2010,31,3:12
9塔里木盆地跃参地区YJ1X井超深层油藏演化显示文摘基于原位方解石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。杨鹏 刘可禹 LI Zhen MCINNES Brent Ian Alexander 刘建良 2022石油勘探与开发2022,49,2:9
10Long-distance ranging with high precision using a soliton microcomb显示文摘Laser-based light detection and ranging(lidar)plays a significant role in both scientific and industrial areas.However,it is difficult for existing lidars to achieve high speed,high precision,and long distance simultaneously.Here,we demonstrate a high-performance lidar based on a chip-scaled soliton microcomb(SMC)that can realize all three specialties simultaneously.Aided 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 eliminated.Combined with an auxiliary dual-frequency phase-modulated laser range finder,the none-dead-zone measurable range ambiguity is extended up to 1500 m.The proposed SMC lidar is experimentally implemented in both indoor and outdoor environment.In 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.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 2020Photonics Research2020,8,12:8
11Vitamin A administration at birth promotes calf growth and intramuscular fat development in Angus beef cattle显示文摘Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesis). As intramuscular adipogenesis is active during the neonatal stage, we hypothesized that vitamin A administration during the neonatal stage would enhance intramuscular adipogenesis and marbling.Methods: Angus steer calves(n = 30), in a completely randomized design, were randomly allotted to three treatment groups at birth, receiving 0, 150,000, or 300,000 IU of vitamin A at both birth and one month of age.A biopsy of the biceps femoris muscle was collected at two months of age. After weaning at 210 d of age, steers were fed a backgrounding diet in a feedlot until 308 d of age, when they were transitioned to a high concentrate finishing diet and implanted with trenbolone/estradiol/tylosin mixture. Steers were harvested at an average of 438 d of age. All diets were formulated to meet nutrient requirements.Results: Weaning weight and weight during the backgrounding phase were linearly increased(P < 0.05) by vitamin A level, though no difference in body weight was observed at harvest. Intramuscular fat of steers at 308 d of age, measured by ultrasound, quadratically increased(P < 0.05) with vitamin A level from 4.0±0.26 % to 4.9±0.26 %.Similarly, carcass marbling score in the ribeye quadratically increased(P < 0.05).Conclusion: Administration of vitamin A at birth increased weaning weight and enhanced marbling fat development.Thus, vitamin A administration provides a practical method for increasing marbling and early growth of beef cattle.Corrine L.Harris Bo Wang Jeneane M.Deavila Jan R.Busboom Martin Maquivar Steven M.Parish Brent McCann Mark L.Nelson Min Du 2018Journal of Animal Science and Biotechnology2018,9,4:7
12Sphingosine-1-phosphate signaling in vasculogenesis and angiogenesis显示文摘Blood vessels either form de novo through the process of vasculogenesis or through angiogenesis that involves the sprouting and proliferation of endothelial cells in pre-existing blood vessels. A complex interactive network of signaling cascades downstream from at least three of the nine known G-protein-coupled sphingosine-1-phosphate (S1P) receptors act as a prime effector of neovascularization that occurs in embryonic development and in association with various pathologies. This review focuses on the current knowledge of the roles of S1P signaling in vasculogenesis and angiogenesis, with particular emphasis on vascular cell adhesion and motility responses.Kelley M Argraves Brent A Wilkerson W Scott Argraves 2010World Journal of Biological Chemistry2010,1,10:6
13Therapeutic neovascularization promoted by injectable hydrogels显示文摘The aim of therapeutic neovascularization is to repair ischemic tissues via formation of new blood vessels by delivery of angiogenic growth factors,stem cells or expansion of pre-existing cells.For efficient neovascularization,controlled release of growth factors is particularly necessary since bolus injection of molecules generally lead to a poor outcome due to inadequate retention within the injured site.In this regard,injectable hydrogels,made of natural,synthetic or hybrid biomaterials,have become a promising solution for efficient delivery of angiogenic factors or stem and progenitor cells for in situ tissue repair,regeneration and neovascularization.This review article will broadly discuss the state-of-the-art in the development of injectable hydrogels from natural and synthetic precursors,and their applications in ischemic tissue repair and wound healing.We will cover a wide range of in vitro and in vivo studies in testing the functionalities of the engineered injectable hydrogels in promoting tissue repair and neovascularization.We will also discuss some of the injectable hydrogels that exhibit self-healing properties by promoting neovascularization without the presence of angiogenic factors.Amrita Pal Brent L.Vernon Mehdi Nikkhah 2018Bioactive Materials2018,3,4:6
14Camouflage Patterning in Maize Leaves Results from a Defect in Porphobilinogen Deaminase显示文摘玉米叶子从导致沿着叶的长轴穿的同种细胞的房间系的极化的房间部门被生产。我们利用了这个 stereotypical 部门模式识别形成违背同种细胞的房间系的叶绿体色素沉着部门的许多异种。这里,我们描述 camouflage1 (cf1 ) 异种,开发 nonclonal,在它的叶子的 yellowgreen 部门。我们由标注的 transposon 克隆 cf1 基因并且决定它编码 porphobilinogen 脱氨基酶(PBGD ) ,在叶绿素和 heme 早工作的酶生合成。当 PBGD 生物化学地被描绘了时,在这基因的可行变化都没在植物被报导。调查在里面 PBGD 的 vivo 功能,我们描绘了 cf1 异种。组织学的分析表明 cf1 黄扇区显示捆鞘的新奇显型房间特定的死亡。轻移动的实验决定经常的光压制了 cf1 部门形成,黑暗 / 轻的转变被要求仅仅在叶开发的一有限时间期间导致黄部门,和那种部门形式。生物化学的实验决定 cf1 异种叶子减少了 PBGD 活动和在绿、黄的区域的酶底层的增加的层次。而且, cf1 黄区域在过氧化氢酶活动显示了减小。一个阀值模型被假设向 cf1 解释上色并且合并光合的细胞区别,清除的反应的氧种,和 PBGD 功能。Mingshu Huanga Thomas L. Slewinski R. Frank Baker , Diane Janick-Buckner Brent Buckner Gurmukh S. Johal David M. Braun 2009Molecular Plant2009,2,4:6
15Spatial phylogenetics of the Chinese angiosperm flora provides insights into endemism and conservation显示文摘The flora of China is well known for its high diversity and endemism. Identifying centers of endemism and designating conservation priorities are essential goals for biodiversity studies.However, there is no comprehensive study from a rigorous phylogenetic perspective to understand patterns of diversity and endemism and to guide biodiversity conservation in China. We conducted a spatial phylogenetic analysis of the Chinese angiosperm flora at the generic level to identify centers of neo-and paleoendemism. Our results indicate that:(i) themajority of grid cells in China with significantly high phylogenetic endemism(PE) were located in the mountainous regions;(ii) four of the nine centers of endemism recognized, located in northern and western China, were recognized for the first time;(iii) arid and semiarid regions in Northwest China were commonly linked to significant PE, consistent with other spatial phylogenetic studies worldwide;and(iv) six highpriority conservation gaps were detected by overlaying the boundaries of China’s nature reserves on all significant PE cells. Overall, we conclude that the mountains of southern and northern China contain both paleo-endemics(ancient relictual lineages) and neo-endemics(recently diverged lineages). The areas we highlight as conservation priorities are important for broad-scale planning, especially in the context of evolutionary history preservation.Xiao-Xia Zhang Jian-Fei Ye Shawn W.Laffan Brent D.Mishler Andrew H.Thornhill Li-Min Lu Ling-Feng Mao Bing Liu You-Hua Chen An-Ming Lu Joseph T.Miller Zhi-Duan Chen 2022Journal of Integrative Plant Biology2022,64,1:5
16Nonalcoholic steatohepatitis: Summary of an AASLD Single Topic Conference显示文摘Brent A. Neuschwander-Tetri Stephen H. Caldwell 2003Hepatology2003,,5:5
17Quantitative Variation in Water-Use Efficiency across Water Regimes and Its Relationship with Circadian, Vegetative, Reproductive, and Leaf Gas-Exchange Traits显示文摘干旱限制点亮收获,导致更低的植物生长和复制。为植物干旱反应重要的一个特点是水使用效率(WUE ) 。我们调查了( 1 ) WUE ,繁殖字符,和植物的特点的联合基因体系结构怎么越过干旱和浇得好的条件变化了,( 2 )是否有不同的发展的库的特点(例如叶气体交换对复制)在他们的基因体系结构的环境敏感不同,并且( 3 )在生理节奏的时期的量的变化是否与在 Brassica rapa 的干旱反应有关。总的来说, WUE 在干旱增加了,首先有气孔的传导力,并且因此浇损失,多于碳固定衰退了。有在干旱的最高的 WUE 的遗传型处于浇得好的条件表示了最低 WUE,并且在两个处理有最大的植物、花的机关。因此,在 WUE 的大变化使一些遗传型能越过环境接近植物、繁殖的特点 optima。基因建筑学越过干旱和浇得好的条件为煤气交换、植物的特点,然而并非为花的特点不同。关联在之间生理节奏并且叶煤气交换的特点是重要的,但是没越过处理变化,显示那个生理节奏的句号不管水可获得性影响生理的功能。这些结果建议 WUE 为在 Brassica rapa 的干旱忍耐是重要的并且为在干旱的增加的 WUE 的人工的选择不导致与 WUE 被相关的另外的特点的不适应的表示。Christine E. Edwards Brent E. Ewers C. Robertson McClung Ping Lou Cynthia Weinig 2012Molecular Plant2012,5,3:5
18CMOS-compatible high-index doped silica waveguide with an embedded silicon-nanocrystal strip for all-optical analog-to-digital conversion显示文摘Passive all-optical signal processors that overcome the electronic bottleneck can potentially be the enabling components for the next-generation high-speed and lower power consumption systems. Here, we propose and experimentally demonstrate a CMOS-compatible waveguide and its application to the all-optical analog-to-digital converter(ADC) under the nonlinear spectral splitting and filtering scheme. As the key component of the proposed ADC, a 50 cm long high-index doped silica glass spiral waveguide is composed of a thin silicon-nanocrystal(Si-nc) layer embedded in the core center for enhanced nonlinearity. The device simultaneously possesses low loss(0.16 dB/cm at 1550 nm), large nonlinearity(305 W^-1∕km at 1550 nm), and negligible nonlinear absorption.A 2-bit ADC basic unit is achieved when pumped by the proposed waveguide structure at the telecom band and without any additional amplification. Simulation results that are consistent with the experimental ones are also demonstrated, which further confirm the feasibility of the proposed scheme for larger quantization resolution.This demonstrated approach enables a fully monolithic solution for all-optical ADC in the future, which can digitize broadband optical signals directly at low power consumption. This has great potential on the applications of high-speed optical communications, networks, and signal processing systems.YUHUA LI KUN ZHU ZHE KANG WAI LOK HO ROY DAVIDSON CHAO LU BRENT ELITTLE SAI TAK CHU 2019Photonics Research2019,7,10:5
19Photonic microwave true time delays for phased array antennas using a 49 GHz FSR integrated optical micro-comb source[Invited]显示文摘We demonstrate significantly improved performance of a microwave true time delay line based on an integrated optical frequency comb source. The broadband micro-comb(over 100 nm wide) features a record low free spectral range(FSR) of 49 GHz, resulting in an unprecedented record high channel number(81 over the C band)—the highest number of channels for an integrated comb source used for microwave signal processing. We theoretically analyze the performance of a phased array antenna and show that this large channel count results in a high angular resolution and wide beam-steering tunable range. This demonstrates the feasibility of our approach as a competitive solution toward implementing integrated photonic true time delays in radar and communications systems.XINGYUAN Xu JIAYANG Wu THACH G.NGUYEN TANIA MOEIN SAI T.CHU BRENT E.LITTLE ROBERTO MORANDOTTI ARNAN MITCHELL DAVID J.Moss 2018Photonics Research2018,6,5:4
20Systematic review and meta-analysis on the association of tuberculosis in Crohn's disease patients treated with tumor necrosis factor-α inhibitors(Anti-TNFα)显示文摘AIM To perform a meta-analysis on the risk of developing Mycobacterium tuberculosis(TB) infection in Crohn's disease(CD) patients treated with tumor necrosis factoralpha(TNFα) inhibitors.METHODS A meta-analysis of randomized, double-blind, placebocontrolled trials of TNFα inhibitors for treatment of CD in adults was conducted. Arcsine transformation of TB incidence was performed to estimate risk difference. A novel epidemiologically-based correction(EBC) enabling inclusions of studies reporting no TB infection cases in placebo and treatment groups was developed to estimate relative odds.RESULTS Twenty-three clinical trial studies were identified, including 5669 patients. Six TB infection cases were reported across 5 studies, all from patients receiving TNFα inhibitors. Eighteen studies reported no TB infection cases in placebo and TNFα inhibitor treatment arms. TB infection risk was significantly increased among patients receiving TNFα inhibitors, with a risk difference of 0.028(95%CI: 0.0011-0.055). The odds ratio was 4.85(95%CI: 1.02-22.99) with EBC and 5.85(95%CI: 1.13-30.38) without EBC.CONCLUSION The risk of TB infection is higher among CD patients receiving TNFα inhibitors. Understanding the immunopathogenesis of CD is crucial, since using TNFα inhibitors in these patients could favor mycobacterial infections, particularly Mycobacterium avium subspecies paratuberculosis, which ultimately could worsen their clinical condition.Brent L Cao Ahmad Qasem Robert C Sharp Latifa S Abdelli Saleh A Naser 2018World Journal of Gastroenterology2018,24,25:4
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