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Journal of Analysis and Testing 2019年第2期3卷 140-149页

作者： Joshua D.Walmsley Joshua W.hill Partha Saha caleb m.hill Department of Chemistry University of WyomingLaramieWY 82071USA

Optically targeted electrochemical cell microscopy(OTECCm)was applied to measure electrocatalytic rates at individual Cu nanoparticles(NPs)under electrolyte conditions relevant to CO_(2) *** electrocatalytic responses from individual NPs were found to exhibit a wide variation in behavior,with significant NP-to-NP variations in the magnitude of electrocata-lytic currents and necessary overpotentials being *** of these quantities with metrics of NP size suggest no significant variations in the inherent electrocatalytic activity of the NPs with *** element simulations of diffusion in this system demonstrate the observed diffusion-limited currents are significantly smaller than expected,attributable to the presence of a significant amount of residual ligand on the surface of the Cu NPs,which were prepared via an organic phase *** results presented here further demonstrate the promise of techniques which employ correlated optical and electrochemical measurements,such as OTECCm,for studying electrocatalysis at individual NPs.

关键词： Electrochemistry Electrochemical microscopy Nanoparticles CO_(2)reduction

Cell-type resolved transcriptomic approaches for dissecting selective vulnerability in neurodgeneration

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Neural Regeneration Research 2024年第7期19卷 1411-1413页

作者： caleb A.Wood Nicholas m.Tran Department of Neuroscience Baylor College of MedicineHoustonTXUSA Department of molecular and Human Genetics Baylor College of MedicineHoustonTXUSA

A common feature among neurodegenerative conditions is that ce rtain neuronal populations are selectively vulnerable to loss(Fu et al.,2018).By corollary,other neurons are selectively resilient,suggesting they may possess unique features that support their survival.U nderstanding the basis of neuronal resilience or vulnerability would provide a logical strategy to identify factors that could be targeted therapeutically.

关键词： selective targeted

Control of Cell Wall Extensibility during Pollen Tube Growth

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molecular Plant 2013年第4期6卷 998-1017页

作者： Peter K. Hepler caleb m. Rounds Lawrence J. Winship Biology Department University of Massachusetts Amherst MA 01003 USA School of Natural Science Hampshire College Amherst MA 01002 USA

In this review, we address the question of how the tip-growing pollen tube achieves its rapid rate of elongation while maintaining an intact cell wall. Although turgor is essential for growth to occur, the local expansion rate is controlled by local changes in the viscosity of the apical wall. We focus on several different structures and underly- ing processes that are thought to be major participants including exocytosis, the organization and activity of the actin cytoskeleton, calcium and proton physiology, and cellular energetics. We think that the actin cytoskeleton, in particular the apical cortical actin fringe, directs the flow of vesicles to the apical domain, where they fuse with the plasma mem- brane and contribute their contents to the expanding cell wall. While pH gradients, as generated by a proton-ATPase located on the plasma membrane along the side of the clear zone, may regulate rapid actin turnover and new polymeri- zation in the fringe, the tip-focused calcium gradient biases secretion towards the polar axis. The recent data showing that exocytosis of new wall material precedes and predicts the process of cell elongation provide support for the idea that the intussusception of newly secreted pectin contributes to decreases in apical wall viscosity and to cell expansion. Other prime factors will be the localization and activity of the enzyme pectin methyl-esterase, and the chelation of calcium by pectic acids. Finally, we acknowledge a role for reactive oxygen species in the control of wall viscosity.

关键词： cell expansion cell walls cytoskeleton dynamics polarity pollen development.

LEAD POISONING IN ANCIENT ROmE: THE STATE OF THE QUESTION

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Journal of Ancient Civilizations 2022年第2期37卷 225-246,276页

作者： Stanley m.Burstein caleb E.Finch California State University Los Angeles The University of Southern California

Introduction Lead pollution as a significant health hazard appears frequently in the news,sometimes spectacularly so as in the case of the recent contamination of the watersupplyof the cityof Flint,michiganbecause of itsuse inlead pipes in the system.'As a result,it is easy to assume that environmental lead pollution is a recent problem,but that is not the *** exposure is,in fact.

关键词： pollution Flint pipes

N-acetyl proline-glycine-proline: implications for neurological disorders

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Neural Regeneration Research 2016年第6期11卷 898-899页

作者： Jeff W.hill Edwin m.Nemoto Department of Neurosurgery University of New Mexico Health Sciences Center

N-acetyl proline-glycine-proline（ac-PGP）is a matrix-derived chemoattractant,or matrikine,produced by the degradation of ***-PGP was first identified in studies of alkali eye injury in rabbits（Pfister et al.,1995）.

关键词： proline glycine acetyl neurological neuronal collagen neutrophil alkali potent chemokine

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干颗粒系统的摩擦流变性研究

Acta mechanica Sinica 2023年第1期39卷 98-109页

作者：满腾张沛葛转佘吉鸿 Kimberly mhill Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of Engineering Westlake University Hangzhou 310024 China College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China Saint Anthony Fall Laboratory and the Department of Civil Environmental and Geo- Engineering University of Minnesota Minneapolis MN 55455 United States

颗粒材料在自然界和工程应用中极为常见,深入理解并合理利用其流变性对于预测与减轻自然灾害以及描述多种工程材料力学性质至关重要.然而,现有研究仍未建立起颗粒之间摩擦特性与颗粒集合体宏观的力学特性之间的物理联系.本文利用离散单... 详细信息

颗粒材料在自然界和工程应用中极为常见,深入理解并合理利用其流变性对于预测与减轻自然灾害以及描述多种工程材料力学性质至关重要.然而,现有研究仍未建立起颗粒之间摩擦特性与颗粒集合体宏观的力学特性之间的物理联系.本文利用离散单元法(DEm)考察了不同颗粒间摩擦系数对定压剪切条件下的颗粒材料的流变性的影响,试图建立基于粒间摩擦的颗粒流变学模型.本研究计算显示,增加颗粒之间的摩擦系数可以显著改变颗粒集合体的整体流变特性,增加颗粒系统的有效摩擦系数µeff,并减小定压剪切条件下的稳态固体体积分数ϕs.在此基础上,本报告提出用于描述不同粒间摩擦特性颗粒材料流变性的无量纲数m,并建立摩擦流变模型.同时考察了m和无量纲颗粒温度Θ之间的关系,分析了摩擦系数对于粒间作用力概率分布函数的影响.进一步延伸了传统的流变模型的应用范围,有助于建立更为普适的颗粒材料本构模型.

关键词：材料力学性质颗粒材料流变学模型概率分布函数颗粒系统摩擦特性无量纲数流变模型

So much for the city:Urban–rural song variation in a widespread Asiatic songbird

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Integrative Zoology 2018年第2期13卷 194-205页

作者： Samuel D.hill Achyut ARYAL matthew D.m.PAWLEY Weihong JI Human-Wildlife Interactions Research Group Institute of Natural and Mathematical SciencesMassey UniversityAucklandNew Zealand School of Life and Environmental Sciences Faculty of ScienceUniversity of SydneySydneyAustralia Department of Forestry and Resource management Toi Ohomai Institute of TechnologyRotoruaNew Zealand Institute of Natural and mathematical Sciences Massey UniversityAucklandNew Zealand

Song plays a fundamental role in intraspecific communication in *** temporal and structural components of songs can vary in different *** include urban habitats where anthropogenic sounds and alteration of habitat structure can significantly affect songbird vocal ***-rural variations in song complexity,song length and syllable rate are not fully *** this study,using the oriental magpie-robin(Copsychus saularis)as a model,we investigated urban-rural variation in song complexity,song length,syllable rate,syllable length and inter-syllable *** urban and rural songs from 7 countries across its natural Asiatic range(Bangladesh,India,malaysia,Nepal,Singapore,Sri Lanka and Thailand),we found no significant differences in oriental magpie-robin song ***,we found significant differences in temporal song variables between urban and rural *** songs and inter-syllable intervals in addition to slower syllable rates within urban sites contributed the most to this *** indicates that the urban environment may have driven production of longer and slower songs to maximize efficient transmission of important song information in urban habitats.

关键词： communication complexity length oriental magpie-robin song syllable

IBm公司用大规模集成电路(LSI)芯片设计了多芯片多层陶瓷组件以提高性能和密度

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现代雷达 1981年第2期 36-42页

作者： Bernard T.Clark Yates m.hill 胡长瑞

介绍 IBm 公司在4300型信号处理机里所使用的两种组件的设计要求和特点。这两种组件由于采用了 LSI 芯片,使得性能上得到很大改善、功率降低、逻辑门的密度和可靠性提高了。在上述应用中,组件逻辑门的平均密度达到了196门/厘米2,为 IBm... 详细信息

介绍 IBm 公司在4300型信号处理机里所使用的两种组件的设计要求和特点。这两种组件由于采用了 LSI 芯片,使得性能上得到很大改善、功率降低、逻辑门的密度和可靠性提高了。在上述应用中,组件逻辑门的平均密度达到了196门/厘米2,为 IBm 公司单片集成系统所达到密度的30倍。在印制电路插件板这一组装级中甚至可以有更大的密度改善。

关键词：多芯片组件芯片多层陶瓷大规模集成电路组件设计组装密度 LSI IBm

A multi-parametric Programming Based Analytic method to Compute Consumer Offer Curve for Reserves

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Journal of modern Power Systems and Clean Energy 2022年第2期10卷 542-546页

作者： Weiye Zheng David J.hill Wenchuan Wu the School of Electrical Power Engineering South China University of TechnologyGuangzhouChina the Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina the Department of Electrical Engineering Tsinghua UniversityBeijingChina

Abstract-An analytic method is proposed to compute the price-reserve offer curve at the consumer level in hierarchical direct load *** convexification of the consumer reserve provision is examined,and the analytic expression of the optimal solution within each critical region is ***,based on multi-parametric programming,a combinatorial enumeration method in conjunction with efficient reduction and pruning strategy is proposed to compute the optimal response of consumers in the whole price *** tests along with an application example in the bi-level aggregator pricing problem demonstrate the merit of this method.

关键词： Direct load control multi-parametric programming price-reserve offer curve analytic solution

A New method for measurements of the Poloidal Rotation Velocities and Wavelength Calibration of X-ray Imaging Crystal Spectrometer in magnetic Fusion Devices

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Plasma Science and Technology 2015年第4期17卷 265-267页

作者：石跃江吕波王福地 m.BITTER K.W.hill 叶民友 University of Science and Technology of China Institute of Plasma Physics Chinese Academy of Sciences Princeton Plasma Physics Laboratory PrincetonNew Jersey 08543USA

A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer（XICS）in magnetic fusion *** this method,the toroidal rotation of plasma is applied for high precise alignment and wavelength calibration of the poloidal *** measurement threshold of poloidal rotation velocity can be lowered to 1-3 km/s with this method.

关键词： X-ray imaging crystal spectrometer wavelength calibration poloidal rotation velocity