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Morphogenetic Action of Neurotransmitters on Regenerating Planarians—A Review

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Biomedical and Environmental Sciences 1993年第4期6卷 327-347页

作者： DAVIDVILLAR davidj.SCHAEFFER Department Department of Veterinary BiosciencesUniversity of Illinois 2001South Lincoln AveUrbana IL 61801USAof Veterinary BiosciencesUniversity of Illinois 2001South Lincoln AveUrbana IL 61801USA

Planarians can be used as invertebrate bioassays to evaluate the role of neurotransmitters on regenerating cells. The influence of the nervous system is crucial to regenerate a normal complete animal. The neurotrophic action of the nervous system has been attributed to the major neurohormones present throughout the animal kingdom. The same type of transmitters found in mammals have been extensively found in many invertebrates, including planarians, but their role in regeneration is unclear. Neurotransmitters and drugs which act on neurohumoral transmission have been used to determine the role of each neurohormonc on regenerating planarians. Biochemical and pharmacological mechanisms of neurohormones on regenerative planarians are reviewed, as is their putative role on regeneration. Correlations with the roles of neurotransmitters in the central nervous system of higher organisms are also addressed.

关键词： Morphogenetic Action of Neurotransmitters on Regenerating Planarians A Review

Low-temperature crystalline lead-free piezoelectric thin films grown on 2D perovskite nanosheet for flexible electronic device applications

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Nano Research 2019年第10期12卷 2559-2567页

作者： Jong-Hyun Kim Sang Hyo Kweon sahn Nahm KU-KIST Graduate School of Converging Science and Technology Korea University145 Anam-roSeongbuk-guSeoul 02841Republic of Korea Department of Material Science and Engineering Korea University145 Anam-roSeongbuk-guSeoul 02841Republic of Korea Department of Mechanical Engineering Kobe University1-1 Rokkodai-choNadaKobe 657-8501Japan

A monolayer of Sr2Nb3Oio(SNO)is deposited on the Pt/Ti/SiCWSi(Pt?Si)or Pt/Ti/polyimide(Pt-Pl)substrate by using the Langmuir-Blodgett method and employed as a seed-layer for the growth of a crystalline(Nai_xKx)NbO3(NKN)film at 350℃.The crystalline NKN film is grown along the[001]direction on the SNO/Pt-Si(or SNO/Pt-PI)*** to the presence of oxygen vacancies in the SNO seed-layer,the NKN film exhibits low ferroelectric properties and large leakage *** ameliorate these properties,the SNO/Pt-Si substrate is annealed in a 50 Torr oxygen atmosphere at 300℃,which removes the oxygen ***,the NKN film deposited on this substrate exhibits promising electrical properties,namely a dielectric constant of 278,dissipation factor of 1.7%,a piezoelectric 8nstant of 175 pm`V^-1,and a leakage current density of 6.47 x 10^-7 A cm^-2 at-0.2 MV *** electrical properties are obtained from the NKN film grown on the flexible SNO/Pt-PI substrate at 350°***,the NKN films grown on the SNO seed-layer at 350°C can be applied to electronic devices with flexible polymer substrates.

关键词： lead-free piezoelectric thin films low-temperature-deposition process two-dimensional(2D)nanosheet seed-layers polymer substrates

Effects of Coal-Water Mixture Properties in Atomization

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Journal of Thermal Science 1994年第1期3卷 49-52页

作者： davidj.Wildman JamesM.Ekmann PittsburghEnergyTechnologyCenter U.S.DepartmentofEnergyPittsburghPA15236USA PittsburghEnergyTechno

Recent suggested CWM applications include using filter cake material and mill tailings as coal *** coal type nor particle size distribution are necessarily well suited for coal-water mixture production. Slumes were prepared with and without additives and attempts were made to characterizetheir rheological properties and atomize these materials. Limits of operation and the value of existingrheological instrumentation and methods were investigated. Effects of changes in particle size distribution are discussed.

关键词： coal-water mixture atomization rheology combustion

Artificial synaptic and self-rectifying properties of crystalline(Na_(1-x)K_(x))NbO_(3)thin films grown on Sr_(2)Nb_(3)O_(10)nanosheet seed layers

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Journal of Materials Science & Technology 2022年第28期123卷 136-143页

作者： In-Su Kim Jong-Un Woo Hyun-Gyu Hwang Bumjoo Kim sahn Nahm Department of Materials Science and Engineering Korea UniversitySeoul 02841Republic of Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoul 02841Republic of Korea

Crystalline(Na_(1-x)K_(x))NbO_(3)(NKN)thin films were deposited on Sr_(2)Nb_(3)O_(10)/TiN/Si(S-TS)substrates at 370°***_(2)Nb_(3)O_(10)(SNO)nanosheets served as a template for the formation of crystalline NKN films at low *** the NKN film was deposited on one SNO monolayer,the NKN memristor exhibited normal bipolar switching characteristics,which could be attributed to the formation and destruction of oxygen vacancy ***,the NKN memristor with one SNO monolayer exhibited artificial synaptic ***,the NKN memristor deposited on two SNO monolayers exhibited self-rectifying bipolar switching properties,with the two SNO monolayers acting as tunneling barriers in the *** conduction mechanism of the NKN memristor with two SNO monolayers in the highresistance state is attributed to Schottky emission,direct tunneling,and Fowler–Nordheim(FN)*** current conduction in this memristor in the low-resistance state was governed by direct tunneling and FN ***,the NKN memristor with two SNO monolayers exhibited large ON/OFF and rectification ratios and artificial synaptic ***,an NKN memristor with two SNO monolayers can be used for fabricating artificial synaptic devices with a cross-point array structure.

关键词： Bipolar switching properties Self-rectifying bipolar switching properties Artificial synaptic properties Crystalline NKN thin film Sr_(2)Nb_(3)O_(10)nanosheet seed layer

Ring-closing Metathesis on anAllyl-terminated Carbosilane Dendrimer

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Chinese Chemical Letters 2005年第1期16卷 4-6页

作者： ChuanJianZHOU RuiFangGUAN ShengYuFENG davidj.BERG StephenR.STOBART SchoolofMaterialsScienceandEngineering Ji＇nan15niversity.Ji＇nan250022 SchoolofChemistry ShandongUniversityJi＇nan2301O0 DepartmentofChemistry UniversityofVictoriaP.O.3065VictoriaB.C.CanadaV8W3P6 SchoolofmaterialsscienceandEngineering ShandongUniversityJi＇nan250071／／SchoolofChemistryShandongUniversityJi＇nan250100

Grubbs’ catalyst was used to prepare a series of carbosilane dendrimers with silacyclopentene peripheral groups. It was found that ring closing metathesis reaction was influenced strongly by the reaction temperatur... 详细信息

关键词： Grubb’s catalyst carbosilane dendrimers metathesis.

多普勒组织成像研究左室壁节段性运动速度──应用新型的左心室模型体外试验

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中华超声影像学杂志 2001年第5期10卷 301-303页

作者：吴瑛 Timothy Irvine Yoshiki Mori 李小奎 davidj.sahn 深圳市人民医院超声诊断科 518020 Clinical Carefor Congenital Heart Disease Oregon Health Sciences University

目的　应用自制的左室模型研究组织多普勒成像 (TDI)测定左室壁节段性运动速度的可靠性和准确性。方法　自制一个左室模型来验证TDI的准确性。该模型以双层气球制作 ,连接一脉冲流量泵 ,分设 8种泵出量 (5 0～ 85ml/每搏 )。将模型浸入... 详细信息

目的　应用自制的左室模型研究组织多普勒成像 (TDI)测定左室壁节段性运动速度的可靠性和准确性。方法　自制一个左室模型来验证TDI的准确性。该模型以双层气球制作 ,连接一脉冲流量泵 ,分设 8种泵出量 (5 0～ 85ml/每搏 )。将模型浸入水槽后 ,以摄像机与TDI同时记录球壁的运动位移和速度。采用GE系统 5超声诊断仪 ,探头频率 5MHz。结果　M型与二维图像显示气球模型形状和壁运动与左心室十分相似。由TDI测得的球壁运动距离与摄像机同步测量距离相关密切 [前壁 :r =0 .97,sx =0 .2 4mm ,平均差±s =(0 .0 4± 0 .2 4)mm ;后壁r =0 .95 ,sx =0 .2 2mm ,平均差±s =(0 .0 3± 0 .2 4)mm]。球壁特定测量点的TDI运动速度亦与摄像所得结果相关密切 [前壁 :r =0 .97,sx =0 .30mm ,平均差±s =- (0 .0 4+0 .2 8)mm ;后壁 :r =0 .97,sx =0 .30mm ,平均差±s =(0 .0 4+0 .2 8)mm]。结论　球体模型提供了一种检测TDI准确性的新方法 ,证明所用TDI系统在测量壁运动距离和速度方面是准确可靠的。

关键词：组织多普勒成像左室壁节段性运动速度解剖学模型

Telomerase turns telomere dysfunction from bad to worse

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Asian Journal of Andrology 2012年第5期14卷 665-666页

作者： sahn-Ho Kim Evelyn R Barrack G Prem Veer Reddy Vattikuti Urology Institute Henry Ford HospitalDetroitMI 48202USA

Telomere integrity is critical for proli- feration and survival of cells. Telomere dysfunction, often resulting from telomere attrition, causes genomic instability leading to cell death or malignant transformation. Telomerase is essential for maintaining te- lomere length and to immortalize cancer cells. While telomere shortening is evident in early stages of prostate cancer,

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Modification by Polychlorinated Biphenyls(PCBs)of Cadmium Induced Lesions in the Planarian Model,Dugesia dorotocephala

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Biomedical and Environmental Sciences 1993年第4期6卷 367-384页

作者： LARRYG.HANSEN WAHEEDAM.TEHSEEN davidj.SCHAEFFER GEORGEL.FOLEY Department DepartmentDepartmentDepartment of Veterinary Biosciences of Veterinary Biosciences of Veterinary Pathobiology University of IUinois2001 S.Lincoln AveUrbanaIL 61801USA

The appearance of abnormal growths on the planarian, Dugesia dorotocephala, in response to cadmium with and without pre-exposure to L-buthionine-R, S-sulfoximine (BSO) and concurrent exposure to the polychlorinated biphenyls (PCBs) Aroclor 1254, PCB 28, PCB 110 or PCB 126 is described. Pigmented rose thorn (PRT) lesions were non-invasive and appeared in response to PCBs. Post-head (PH) lesions developed in up to 100% of the animals within 6-20 days post-dosing, progressed rather rapidly and were highly invasive. Round tail tip (RTT) lesions appeared in lower frequencies within 10-30 days, but progressed extremely rapidly resulting in tail loss within 48 h. We have referred to these types of lesions as 'tumors', but they are not necessarily characteristic of vertebrate neoplasms.PCBs interacted with cadmium in a complex way, in some cases increasing total lesions and decreasing time-to-lesion and in other cases having the opposite effects. A three-factor (PCB, PCB dose, Cd dose) nested analysis of variance model was used to determine lesion rates in order to compare PCB potencies as potentiators or antagonists. The Aroclor mixture was always the least potent co-toxicant but appeared to be the most potent antagonist; the coplanar PCB 126 was the most potent co-toxicant. The complex response surfaces and the lack of stoichiometry in dose-response relationships indicate that multiple mechanisms are responsible for PH and RTT lesions in planarians. These results emphasize the complexity of PCB toxicities and suggest further studies to validate the planarian model as a screen for combinations or environmental mixtures which may have altered biological potency in other species.

关键词： PCBs)of Cadmium Induced Lesions in the Planarian Model,Dugesia dorotocephala Modification by Polychlorinated Biphenyls

Assessment of Left Ventricular Radial Deformation by Speckle Tracking Imaging

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2009年第5期29卷 669-672页

作者：潘敏罗浩 Ashraf Muhammad Schultheis Judy 李小葵 David J. sahn Department of Ultrasound Peking University Shenzhen Hospital Tongji Medical College Huazhong University of Science and Technology The Cardiac Fluid Dynamics and Imaging Lab Oregon Health & Science University

The left ventricular radial strain in the inner and outer layers was evaluated by using two-dimensional speckle tracking imaging （2DS）. Twenty-five piglets were studied. The short axis views were acquired. Peak systolic radial strain was measured from 6 circumferential points related to 6 standard segments in the inner and outer layers respectively using 2DS methods. The peak positive first derivative （dp/dt） of left ventricular pressure was compared to the radial strain from 2DS. The inner band showed higher peak radial strain values as compared to the outer band at all of the segments （P〈0.0001）, but the differences had significance just in anteroseptal, posterior, inferior and septal segments （P〈0.05）. Good correlation could be found between radial strain of inner and outer layers and peak dp/dt （P〈0.001）. These preliminary results showed that the degree of local deformation or wall thickening of the ventricular wall in its inner layer was more obvious than its outer layer. It is suggested that the 2DS technique is useful and sensitive for better understanding the regional and global myocar- dial motion and its relationship to the complex architecture of myocardium.

关键词： echocardiography speckle tracking imaging strain, radial