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Sound Modulation in Singing Katydids Using Ionic Polymer-Metal Composites （IPMCs）

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Journal of Bionic Engineering 2013年第4期10卷 464-468页

作者： Yan Zhou Cheng-Wei Chiu Carlos J. Sanchez Jorge M. Gonzalez Benjamin Epstein david rhodes S. Bradleigh Vinson Hong Liang Materials Science and Engineering Texas A&M University College Station TX 77843 USA Department of Mechanical Engineering Texas' A&M University College Station TX 77843 USA Department of Entomology Texas A&M University College Station TX77843 USA Department of Plant Science California State University Fresno CA 93740 USA OpCoast LLC Brick NJ08723 USA

Many insect families have evolved to produce and detect complex singing patterns for the purposes of mating, display of dominance, predator escape, and other needs. While the mechanisms of sound production by insects have been thoroughly studied, man-machine exploitation of such mechanisms has remained unreported. We therefore describe a method to modulate the frequency spectrum in the chirp call of a singing insect, Gampsocleis gratiosa （Orthoptera： Tettigoniidae）, a large katydid indigenous to China and commonly known as Guo Guo or Chinese Bush Cricket. The chirp modulation was achieved through the contact of a ribbon of lonic Polymer-Metal Composite （IPMC） against wing of the insect. The IPMC effectively served as an actuator when a small DC voltage was applied to the ribbon＇s faces. By applying a sequential on/off voltage waveform to the IPMC ribbon, the katydid＇s chirp was modulated in a corresponding manner. This configuration can be used as part of a broader application of using singing insects to harness their acoustic power to produce and propagate machine-induced messages into the acoustic environment.

关键词： chirp modulation katydid IPMC

Biosynthesis and molecular actions of specialized 1,4-naphthoquinone natural products produced by horticultural plants

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Horticulture Research 2016年第1期3卷 88-104页

作者： Joshua R Widhalm david rhodes Department of Horticulture and Landscape Architecture Purdue University625 Agriculture Mall DriveWest LafayetteIN 47907-2010USA

The 1,4-naphthoquinones(1,4-NQs)are a diverse group of natural products found in every kingdom of ***,including many horticultural species,collectively synthesize hundreds of specialized 1,4-NQs with ecological roles in plant–plant(allelopathy),plant–insect and plant–microbe *** horticultural plants producing 1,4-NQs have also served as sources of traditional medicines for hundreds of *** a result,horticultural species have been at the forefront of many basic studies conducted to understand the metabolism and function of specialized plant 1,*** 1,4-NQ natural products derived from horticultural plants have also emerged as promising scaffolds for developing new *** this review,the current understanding of the core metabolic pathways leading to plant 1,4-NQs is provided with additional emphasis on downstream natural products originating from horticultural *** overview on the biochemical mechanisms of action,both from an ecological and pharmacological perspective,of 1,4-NQs derived from horticultural plants is also *** addition,future directions for improving basic knowledge about plant 1,4-NQ metabolism are discussed.

关键词： metabolism hundreds specialized

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销售效力如何向“赢”看齐

经理人 2003年第2期 73-75页

作者： david rhodes Lionel Are Bruce Holley 波士顿咨询公司伦敦办公室波士顿咨询公司巴黎办公室波士顿咨询公司纽约办公室

每位销售人员就像是出租车司机,一旦达到了他们的目标区域,就很难继续激励他们。一位著名的美国橄榄球教练曾评述到:胜利不是一切,但它是唯一的。这样的观点听来有些陈腐,但对销售队伍来讲却非常正确。差一点就能卖出一件商品是毫无价... 详细信息

每位销售人员就像是出租车司机,一旦达到了他们的目标区域,就很难继续激励他们。一位著名的美国橄榄球教练曾评述到:胜利不是一切,但它是唯一的。这样的观点听来有些陈腐,但对销售队伍来讲却非常正确。差一点就能卖出一件商品是毫无价值的。幸运的是,销售人员可以培养。激励团队销售部门可以'生产'销售,但他们不是机器。

关键词：销售人员激励机制客户管理市场营销销售效力

Rodent biology and ecologically based rodent management(EBRM)-25 years of progress through promoting multidisciplinary research

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Integrative Zoology 2024年第1期19卷 2-7页

作者： Grant R. SINGLETON Lyn A. HINDS rhodes MAKUNDI Steven R. BELMAIN Natural Resources Institute University of Greenwich Kent UK CSIRO Health and Biosecurity Canberra ACT Australia African Centre of Excellence for Innovative Rodent Pest Management and Biosensor Technology Development Sokoine University of Agriculture Morogoro Tanzania Institute of Pest Management Sokoine University of Agriculture Morogoro Tanzania

“During rodent outbreak years in eastern Africa,lo-cally,more than 80%of the potential harvest may be lost,but even in non-outbreak periods,rodents cause chronic damage to crops….The pest rodent story in Africa in-volves several species embedded in a broad and variable landscape with highly variable densities.”(Leirs et al.2010).

关键词： damage crops

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无砟轨道与桥梁结构的配合

西铁科技 2017年第1期 44-46,33页

作者： david rhodes D R Squared Michael Baxter 轨道国际咨询公司

新规范与标准的制订有助于无缝线路长大桥梁上最终取消钢轨伸缩接头，使高速铁路采用无砟轨道更加经济。

关键词：无砟轨道桥梁结构伸缩接头长大桥梁无缝线路高速铁路钢轨

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在经济衰退时期获取优势

董事会 2009年第5期 95-97页

作者： david rhodes Daniel Stelter 胡宇飞

确保公司拥有充足的现金流,这不仅是为了防备流动性短缺引起的突发事件,更重要的是要让公司具备一定的投资能力,只有如此。

关键词：经济衰退时期经济危机公司坏消息领导者市场

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

One-dimensional monotone nonautonomous dynamical systems

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Science China Mathematics 2024年第2期67卷 281-314页

作者： david Cheban Faculty of Mathematics and Computer Science Laboratory of Fundamental and Applied MathematicsMoldova State UniversityChisinau 2009Moldova

This work is devoted to the study of the dynamics of one-dimensional monotone nonautonomous(cocycle) dynamical systems. A description of the structures of their invariant sets, omega limit sets,Bohr/Levitan almost periodic and almost automorphic motions, global attractors, and pinched and minimalsets is given. An application of our general results is given to scalar differential and difference equations.

关键词： one-dimensional dynamics pinched and minimal sets global attractors monotone nonautonomous cocycle almost periodic solutions scalar differential/difference equations

Kerogen Kinetic Distributions and Simulations Provide Insights into Petroleum Transformation Fraction (TF) Profiles of Organic-Rich Shales

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Journal of Earth Science 2024年第3期35卷 747-757页

作者： david A.Wood DWA Energy Limited Lincoln LN59JPUnited Kingdom

Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·*** activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and *** characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A *** similarities and differences are observed between the TF profile values of the two *** similarities support the spread of E-A values involved in shale pyrogram best *** differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions *** results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A *** contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale *** profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.

关键词： transformation fraction profiles simulated S2 pyrograms multiple heating rates kerogen/shale kinetics S2 pyrogram fitting techniques kerogen petroleum research.