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EFFICIENCY ANALYSIS OF DOUBLE CRANK RING-PLATE-TYPE PIN-CYCLOIDAL GEAR PLANETARY DRIVE

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Chinese Journal of Mechanical Engineering 2003年第3期16卷 252-255页

作者： LiXin HeWeidong LindaSchmidt LiLixing DepartmentofMechanicalEngineenng UniversityofMarylandMarylandU.S.A. DepartmentofMechanicalEngineering DalianRailwayInstituteDalian116028China DeparlmentofMechanicalEngineering UniversityofMarylandMarylandU.S.A.

From the general formula for calculating the efficiency of planetary geartrains, the efficiency of the double crank ring-plate-type pin-cycloidal gear planetary drive isderived. To prove the theory, an experimental study has been conducted. The tested value of theefficiency of a sample set of the new-type drive in the experiment agrees with the calculated *** shows that the new-type drive is of not merely high bearing capacity, but also quite highefficiency.

关键词： Double crank ring-plate-type Pin-cycloidal gear planetary drive Meshefficiency

Genetic regulation of programmed cell death in Drosophila

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Cell Research 2000年第3期10卷 193-204页

作者： LEE CHENG-YU, ERIC H BAEHRECKE (l Center for Agricultural Biotechnology, University of Maryland Biotechnology institute, College Park, Maryland 20742,USA Department of Biology, University of Maryland, College Park, Maryland 20742, USA) CenterforAgriculturalBiotechnology UniversityofMarylandBiotechnologyInstituteDepartmentofBiologyUniversityofMarylandCollegePark20742USA.

Programmed cell death plays an important role in maintaining homeostasis during animal development, and has been conserved in animals as different as nematodes and humans. Recent studies of Drosophila have provided valuable information toward our understanding of genetic regulation of death. Different signals trigger the novel death regulators rpr, hid, and grim, that utilize the evolutionarily conserved iap and ark genes to modulate caspase function. Subsequent removal of dying cells also appears to be accomplished by conserved mechanisms. The similarity between Drosophila and human in cell death signaling pathways illustrate the promise of fruit mes as a model system to elucidate the mechanisms underlying regulation of programmed cell death.

关键词： Apoptosis autophagy phagocytosis development.

The origin of herbivory on land： Initial patterns of plant tissue consumption by arthropods

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Insect Science 2007年第4期14卷 259-275页

作者： CONRAD LABANDEIRA DepartmentofPaleobiology NationalMuseumofNaturalHistorySmithsonianInstitutionWashingtonDCandDepartmentofEntomologyUniversityofMarylandCollegeParkMarylandUSA

The early fossil record of terrestrial arthropod herbivory consists of two pulses. The first pulse was concentrated during the latest Silurian to Early Devonian （417 to 403 Ma）, and consists of the earliest evidence for consumption of sporangia and stems （and limited fungivore borings）. Herbivorization of most of these tissues was rapid, representing 0 to 20 million-year （m.y.） lags from the earliest occurrences of these organs in the fossil record to their initial consumption （Phase 1）. For approximately the next 75 m.y., there was a second, more histologically varied origination and expansion of roots, leaves, wood and seeds, whose earliest evidence for herbivorization occurred from the Middle-Late Mississippian boundary to the Middle Pennsylvanian （327 to 309 Ma）. The appearance of this second herbivory pulse during the later Paleozoic （Phase 2） is accompanied by major lags of 98 to 54 m.y. between times of appearance of each of the four organ and tissue types and their subsequent herbivory. Both pulses provide a context for three emerging questions. First is an explanation for the contrast between the near instantaneous consumption of plant tissues during Phase 1, versus the exceptionally long lags between the earliest occurrences of plant tissues and their subsequent herbivorization during Phase 2. Second is the identity of arthropod herbivores for both phases. Third is the cause behind the overwhelming targeting of seed-fern plant hosts during Phase 2. Regardless of the answers to these questions, the trace fossil record of plant-arthropod associations provides primary ecological data that remain unaddressed by the body-fossil record alone.

关键词： herbivory ecological lag Devonian Carboniferous arthropod plant-insectinteractions wood boring seed predation folivory fecal pellet response tissue sporangia,roots stems

ntrinsically disordered proteins and prostate ancer： pouring new wine in an old bottle

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Asian Journal of Andrology 2016年第5期18卷 659-661页

作者： Prakash Kulkarni ProteinBiophysics&StructuralBiologyLaboratory InstituteforBioscienceandBiotechnologyResearchUniversityofMarylandRockvilleMD20850USA

An inconvenient truth in urology is that .despite decades of intense research,prostate cancer （PCa） has remained one of the most prevalent cancers and leading cause of cancer-related deaths in men, particularly in t... 详细信息

关键词： ACTIVE SURVEILLANCE ANDROGEN RECEPTOR PROMISCUITY NETWORKS

Is ‘Superluminal＇ Light Propagation Possible in Dispersive Media？

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Chinese Physics Letters 2004年第5期21卷 770-773页

作者：陈凯吴令安史砚华 LaboratoryofOpticalPhysics InstituteofPhysicsChineseAcademyofSciencesBeijing100080 DepartmentofPhysics UniversityofMarylandBaltimoreCountyBaltimoreMaryland21250USA

In a dispersive medium, different monochromatic modes of light have different phase velocities. Under special circumstances, a superposition of these modes results in an interesting effect wherein the group velocity (the velocity at which the peak of the wavepacket propagates) could be greater than c or even negative although the phase velocities of the modes are all less than c. Can this superluminal group velocity be used for information transfer? We show here that the"superluminal"effect is due to a coherent optical wave superposition effect. Whatever the velocity of the"peak", the whole pulse cannot travel with a speed greater than the fastest phase velocity of its component modes. Thus the maximum speed for information transfer, which involves the sending of a finite pulse, cannot be greater than the maximum phase velocity in the medium.

关键词： Light velocity

AN ILLUSTRATIVE STUDY ON LOCAL LANDSCAPE AND ITS LONG-TERM CHANGES BASED ON IKONOS AND HISTORICAL AERIAL PHOTO

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Chinese Geographical Science 2004年第2期14卷 162-169页

作者： RUANRen-zong ErieCELLISt DepartmentofUrbanandResourcesSciences NanjingUnicersityNanjing210093P.R.China DepartmentofGeographyandEnvironmentalSystems UniversityofMaryland.BaltimoreCountyUSA

Nowadays, the research works on landscape at fine scales using high-resolution images are *** research is based on the analysis of the combination of remote sensing data (IKONOS imagery acquired in 2002and historical aerial photo taken in 1942). In the paper, the ecotopes in Qiujiadou and Xishao villages in Yixing City of Jiangsu Province in 1942 and 2002 were compared and landscape changes as well as the causes of the considerable changes were analyzed. It was found that the ecotope changes were at greater level in some aspects such as water surface and perennial vegetation coverage etc. This study at fine scale is globally significant for the rural areas, especially for the subsistence agricultural land, which occupies larger percentage in the earth. And it analyzes the structure of landscape based on a new landscape classification system-stratifications method.

关键词： IKONOS aerial photo landscape ecotope

Local measurement for structural health monitoring

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Earthquake Engineering and Engineering Vibration 2005年第1期4卷 165-172页

作者：祁贵仲郭迅齐霄斋董伟民 P.Chang InfraTech Inc.SilverSpringMarylandUSA InstututeofEngineeringMechanics CEAHarbinChina RiskManagementSolution SanFranciscoCaliforniaUSA DepartmentofCivilEngineering UniversityofMaryland／CollegeParkUSA

Localized nature of damage in structures requires local measurements for structural health monitoring. The local measurement means to measure the local, usually higher modes of the vibration in a structure. Three fundamental issues about the local measurement for structural health monitoring including (1) the necessity of making local measurement, (2) the difficulty of making local measurement and (3) how to make local measurement are addressed in this paper. The results from both the analysis and the tests show that the local measurement can successfully monitor the structural health status as long as the local modes are excited. Unfortunately, the results also illustrate that it is difficult to excite local modes in a structure. Therefore, in order to carry structural health monitoring into effect, we must (1) ensure that the local modes are excited, and (2) deploy enough sensors in a structure so that the local modes can be monitored.

关键词： structure health monitoring local measurement local modes higher modes local modes excitation sensors structural vibration

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急诊操作

中华急诊医学杂志 2015年第12期24卷 1482-1484页

作者：肖锋于露陈都步涨江利冰郑辛甜葛赟 universityofmaryland USA

张力性气胸的穿刺减压（的新位置）Michael Winters穿刺减压-我们教的位置正确吗？张力性气胸会常导致循环衰竭和心肺骤停。在不能立即放置胸导管的情况下，传统的穿插减压教学是在第二个肋间隙和锁骨中线交叉点插入一个5cm的套管针。

关键词：张力性气胸操作急诊穿刺减压心肺骤停循环衰竭锁骨中线胸导管

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中毒

中华急诊医学杂志 2014年第11期23卷 1301-1304页

作者：肖锋 Dr_ Xiao US universityofmaryland USA

马里兰急诊医学必知（Maryland Emergency Medicine Pearls） QT 间期与美沙酮过量使用后果的关系 Bryan Hayes 翻译：步涨校对：陈都肖锋美沙酮会使QT间期延长.而QT间期延长的程度是否与其过量使用后更坏的结局有关呢？一项研究表明... 详细信息

马里兰急诊医学必知（Maryland Emergency Medicine Pearls） QT 间期与美沙酮过量使用后果的关系 Bryan Hayes 翻译：步涨校对：陈都肖锋美沙酮会使QT间期延长.而QT间期延长的程度是否与其过量使用后更坏的结局有关呢？一项研究表明,美沙酮过量后,QT间期延长至470、450及447.5 ms后,患者死亡、插管及呼吸停止的预测的敏感性及特异性（95％CI）分别为：87.5 （47.3～99.7）,86.8 （74.7～94.5）,及77.3 （62.2 ～88.5）.临床应用：QT间期延长有助于美沙酮过量所致后果的预测.但是在该研究中,QT间期阈值并不能算作明显延长.长期慢性但非过量使用美沙酮的患者,其QT间期的基线较本研究中过量使用后的更长.许多因素对美沙酮过量使用的最终转归都有影响.

关键词： QT间期延长过量使用中毒美沙酮急诊医学呼吸停止临床应用特异性