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Chemo-dynamical modelling with Schwarzschild's method

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Research in Astronomy and Astrophysics 2018年第12期18卷 1-8页

作者： Richard john long Shude Mao National Astronomical Observatories Chinese Academy of Sciences Jodrell Bank Centre for Astrophysics School of Physics and Astronomy The University of Manchester Physics Department and Tsinghua Centre for Astrophysics Tsinghua University

We extend Schwarzschild’s dynamical modelling method to model absorption line strength data as well as the more usual luminosity and kinematic *** approach draws on earlier published work by the first author with the Syer & Tremaine made-to-measure(M2M) dynamical modelling method and uses similar ideas to create a chemo-Schwarzschild *** apply our extended Schwarzschild method to the same four early type galaxies(NGC 1248, NGC 3838, NGC 4452,NGC 4551) as the chemo-M2M work, and are able to recover successfully the 2D absorption line strength for the three lines we model(Hβ, Fe5015, Mg b).We believe that this is the first time Schwarzschild’s method has been used in this *** techniques developed can be applied to modelling other aspects of galaxies, for example age and metallicity data coming from stellar population modelling, and are not specific to absorption line strength data.

关键词： galaxies:abundances galaxies:formation galaxies:individual(NGC 1248,NGC 3838,NGC 4452,NGC 4551) galaxies:kinematics and dynamics galaxies:structure methods:numerical

Wolfberry tree dual-model detection method and orchard target-oriented fertilization system based on photoelectric sensors

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 65-73页

作者： Shuo Yang Changyuan Zhai john long Bo Zhang Hanzhe Li College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYanglingShaanxi 712100China Department of Biosystems and Agricultural Engineering Oklahoma State UniversityStillwaterOK 74078USA

Orchard target-oriented fertilizing with on-board sensor technology can improve fertilizer efficiency and reduce environmental *** sensors are widely used for object detection because of their low cost and fast response *** paper presents a Wolfberry tree dual-model detection method and the design of an orchard target-oriented variable-rate fertilization system based on photoelectric *** dual-model detection method includes the Trunk Detection Model(TDM)and Canopy Detection Model(CDM),which can be applied for Wolfberry orchards at the green cluster and mature stages,respectively.A target-oriented fertilization system was designed using the dual-model method,and tested in the lab and Chinese Wolfberry *** laboratory test results showed that the average center offset distances on the condition of detecting trunks,continuous canopies,and discontinuous canopies were 4.1 cm,9.1 cm and 13.1 cm,*** system could ignore the signals from canes when their diameters were less than 16 mm,and also could determine the gaps within a tree when they were less than 21 *** orchard test results showed that the system accomplished target-oriented fertilization 95 times for 92 trees at the mature *** results indicated that the dual-model detection method could be used for Wolfberry trees or other trees with similar canopy changes at different growth stages.

关键词： orchard fertilizer target-oriented fertilization variable rate fertilization photoelectric sensor wolfberry orchard

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果园风送喷雾精准控制方法研究进展

农业工程学报 2018年第10期34卷 1-15页

作者：翟长远赵春江 Ning Wang john long 王秀 Paul Weckler 张海辉西北农林科技大学机械与电子工程学院杨凌712100 国家农业信息化工程技术研究中心北京100097 Department of Biosystems and Agricultural Engineering Oklahoma State UniversityStillwaterOK 74078USA 农业部农业物联网重点实验室杨凌712100 陕西省农业信息感知与智能服务重点实验室杨凌712100

果园风送喷雾技术与装备正在朝着精准化和智能化方向发展。果园喷雾控制对象主要为喷施药量和风力供给量,二者需要协同精准调控,其按需调控的前提是果园靶标精准探测。该文从果园靶标探测方法、喷施药量控制方法、风力调控方法 3个方面... 详细信息

果园风送喷雾技术与装备正在朝着精准化和智能化方向发展。果园喷雾控制对象主要为喷施药量和风力供给量,二者需要协同精准调控,其按需调控的前提是果园靶标精准探测。该文从果园靶标探测方法、喷施药量控制方法、风力调控方法 3个方面对现有研究进展进行综述,阐述了基于光电感知、超声波传感、激光雷达、图像、光谱和电子鼻技术探测果树位置、冠层外形轮廓、冠层体积、冠层内部结构、枝叶稠密程度、病虫害程度等特征信息的技术方法;分析了喷施药量调控方法中管道总药量控制方法在管道设计、混药方式、药液流量控制策略方面技术和产品化上取得的巨大突破,以及喷头药量独立控制方法研究方面获得的大量成果;综述了果园风送喷雾风速风量需求理论原则、风场雾场建模方法、风力调控方法与调控装备研究进展,指出了其基本理论原则、建模调控方法等科学问题还有待深入探索。同时,还分析了目前研究在果园靶标探测方法、喷施药量调控方法和风送喷雾风力调控方法中面临的困难和挑战,主要包括冠层稠密程度和病虫害程度高效感知方法探索、靶标风力需求普适模型构建、风场建模风力按需调控方法研究和精准喷雾技术与系统集成开发。最后指出了果园风送喷雾精准控制方法未来发展方向:1)果园靶标冠层枝叶稠密程度和病虫害程度在线探测方法将成为新的研究热点;2)果园风送喷雾风速风量供给需求理论原则、风场快速模拟仿真和风力调控方法与装备是未来重要研究方向;3)随着高新科技的涌现,科研院所和公司有望在果园喷雾药量和风力调控系统优化设计及精准喷雾机系统集成研发方面获得更大发展。

关键词：农业机械喷雾果园靶标探测变量技术风力调控

果园风送喷雾机的改进设计与喷雾高度调控模型构建

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西北农林科技大学学报（自然科学版） 2018年第9期46卷 148-154页

作者：翟长远徐莎 john long 李瀚哲张波朱瑞祥西北农林科技大学机械与电子工程学院陕西杨凌712100 农业部农业物联网重点实验室陕西杨凌712100 Department of Biosystems and Agricultural Engineering Oklahoma State UniversityStillwaterOKUSA 74078

【目的】针对第一代果园喷雾机存在的风箱角度不能电动控制且调节精度不高、传动装置设计欠合理和体积偏大等问题进行改进,并建立喷雾高度调控模型,为新一代果园喷雾机的设计提供参考。【方法】对喷雾机导流风箱的固定方式、传动方案和... 详细信息

【目的】针对第一代果园喷雾机存在的风箱角度不能电动控制且调节精度不高、传动装置设计欠合理和体积偏大等问题进行改进,并建立喷雾高度调控模型,为新一代果园喷雾机的设计提供参考。【方法】对喷雾机导流风箱的固定方式、传动方案和通过性能进行了改进,并通过喷雾沉积分布试验及数学方程拟合,建立沉积分布重心高度、喷雾宽度与风箱角度之间的数学模型。【结果】与改进前相比,该喷雾机不仅支持风箱角度电动精确调控,而且其理论功耗还减少了8%,长度尺寸减小了32.6%。风箱旋转角度对喷雾机尺寸影响的测试结果表明,旋转角度对风箱组宽度有一定的影响,旋转角度为最大值30°时风箱组宽度最大,为0.95m,但仍然小于喷雾机轮距1.0m;风箱旋转角度对喷雾机高度基本没有影响。改进后的喷雾机喷雾沉积分布试验表明,风箱与铅垂线夹角分别为0°,15°和30°时,喷雾沉积分布重心高度分别为1.14,1.55和2.20m,70.7%的药量分别垂直集中分布于0.72~1.56,1.15~1.94和1.71~2.69m,拟合得到的沉积分布重心高度、喷雾宽度和风箱角度之间的数学方程均为线性方程,其R2值分别为0.982和0.996。【结论】改进后喷雾机支持喷雾高度电动精确调节;所建立的喷雾高度智能调控模型可为果园喷雾机的改进完善提供支持。

关键词：风送喷雾机风箱旋转角喷雾高度调控模型果园

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鱼类的崛起

磺胺类抗生素的反相LC分析：应用Agilent TC—C18分析磺胺类抗生素

作者： (澳)约翰·A. 朗(john A. long)

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流程工业 2006年第11期 64-64,53页

作者： William long john Henderson Ronald Majors 美国Agilent公司

使用新型反相液相色谱法Agilent TC—C18，可以很好地分离磺胺类抗生索的活性成分，本文详细报道了这项技术。

关键词：反相液相色谱法磺胺类 C18 抗生素 TC 应用 LC 活性成分

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang Yu-Wen Alvin Huang john Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB

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希望螈:手指从这里起源

环球科学 2020年第13期 42-49页

作者：约翰·A·朗里夏尔·克卢捷卢静(翻译) 澳大利亚弗林德斯大学加拿大魁北克大学中国科学院古脊椎动物与古人类研究所

手是我们最熟悉的身体部位,一只手有5根手指,它们灵活又强壮,能轻抚爱人、能弹钢琴,也能抓起铁锤。人的大多数日常活动,从穿衣服、开汽车到煮饭、发微信,全都要依靠手。但对于手的演化,特别是它的起源,我们的认识依然不够。其他长了四... 详细信息

手是我们最熟悉的身体部位,一只手有5根手指,它们灵活又强壮,能轻抚爱人、能弹钢琴,也能抓起铁锤。人的大多数日常活动,从穿衣服、开汽车到煮饭、发微信,全都要依靠手。但对于手的演化,特别是它的起源,我们的认识依然不够。其他长了四肢的动物,也就是所谓的“四足动物”的手看起来和我们的很不一样:鸟和蝙蝠的手构成了精巧的翅膀;大象的手(和足)支撑了它们树干一样的四肢和沉重的躯干,但这些手(足)的基本结构都是一样的。

关键词：四足动物微信身体部位弹钢琴手指起源四肢

China’s biggest, most neglected health challenge: non-communicable diseases

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Infectious Diseases of Poverty 2013年第1期2卷 47-52页

作者： Shenglan Tang john Ehiri Qian long Duke Global Health Institute Duke UniversityDurhamNCUSA Mel and Enid Zuckerman College of Public Health University of ArizonaTucsonAZUSA School of Public Health and Management Chongqing Medical UniversityChongqingPR China

Background:Over the past two decades,international health policies focusing on the fight against the human immunodeficiency virus/acquired immunodeficiency syndrome(HIV/AIDS),tuberculosis(TB),malaria,and those diseases that address maternal and child health problems,among others,have skewed disease control priorities in China and other Asian *** these are important health problems,an epidemic of chronic,non-communicable diseases(NCDs)in China has accounted for a much greater burden of disease due to the ongoing rapid socioeconomic and demographic ***:Although NCDs currently account for more than 80%of the overall disease burden in China,they remain very low on the nation’s disease control priorities,attracting marginal investment from central and local *** leaves the majority of patients with chronic conditions without effective *** organizations and national governments have recognized the devastating social and economic consequences caused by NCDs in low-and middle-income countries,including ***,few donor-funded projects that address NCDs have been implemented in these countries over the past *** to a lack of strong support from international organizations and national governments for fighting against NCDs,affected persons in China,especially the poor and those who live in rural and less developed regions,continue to have limited access to the needed *** associated with frequent health facility visits and regular treatment have become a major factor in medical impoverishment in *** article argues that although China's ongoing health system reform would provide a unique opportunity to tackle current public health problems,it may not be sufficient to address the emerging threat of NCDs unless targeted steps are taken to assure that adequate financial and human resources are mapped for effective control and management of NCDs in the ***:The Chinese government need

关键词： Non-communicable diseases Infectious diseases Evidence-based public health interventions Health system reform China