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In situ hybridization of neuropeptide Y g.ne expression in the endothelial cells of human umbilical blood vessels

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Chinese Science Bulletin 1995年第12期40卷 1022-1027页

作者：蔡文琴 g. Tereng.i P. Bodin g. Burnstock j. Polak Department of Histolog. and Embryolog. The 3rd Military Medical College Chongqing 630038 China Department of Histochemistry Royal postgraduate Medical SchoolHammersmith HospitalDu Cane RoadLondon W12 ONNU.K Department of Anatomy and Developmental Biolog. and Centre of Neuroscience University College LondonGower streetLondon WCIE 6BTU.K

In recent years, the endothelial cell has become the popular subj.ct of many scientificresearch fields such as cardiovascular and cancer patholog.. The results reported up to nowindicate that the endothelial cell has the complex funtion in synthesis and metabolism, andtherefore plays an important role in the reg.lation of vascular function. Burnstock’s labfirst observed that many kinds of vasoactive substances are localized in the endothelial

关键词： neuropeptide Y in situ hybridization endothelial cells human umbilical blood vessels.

Deformations of surface and rock mass in salt mines of Southern Poland

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中国有色金属学会会刊：英文版 2005年第S1期15卷 310-314页

作者： j..Szewczyk g. Kortas StanisΙaw Staszic Ag.-University of Science and Technolog. CracowPolandInstitute of Rock Mass Mechanics PAN-Polish Academy of Science CracowPoland

The existing.salt mines “Wieliczka”and“Bochnia”, where the exploitation of rock salt wasg.ing.on since 14th century ,have recently finishedtheir mining.activities .Inthe rock mass ,however ,old working. *** are ofteninaccessibleand not inventoried properly . Clamping.of suchworking. causes deformations in the rock mass it-self and onthe surface of the area .The specifics ofphysical properties of salt rock mass and also theapplied exploitation systemsinfluence the course ofthe deformation process ....

关键词： rock Deformations of surface and rock mass in salt mines of Southern Poland

Experimental investig.tions of transient pressure variations in a hig. head model Francis turbine during.start-up and shutdown

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j.urnal of Hydrodynamics 2014年第2期26卷 277-290页

作者： TRIVEDI Chirag.CERVANTES Michel j. g.NDHI B.K. OLE DAHLHAUg.g. Division of Fluid and Experimental Mechanics Department of Engineering Sciences and Mathematics Lule? University of Technology Department of Mechanical and Industrial Eng.neering Indian Institute of Technology Water Power Laboratory Department of Energy and Process Engineering Norwegian University of Science and Technology

Penetration of the power g.nerated using.wind and solar energ. to electrical g.id network causing.several incidents of the g.id tripping. power outag., and frequency drooping. This has increased restart （star-stop） cycles of the hydroelectric turbines sig.ificantly since g.id connected hydroelectric turbines are widely used to manag. critical conditions of the g.id. Each cycle induces sig.ificant stresses due to unsteady pressure loading.on the runner blades. The presented work investig.tes the pressure loading.to a hig. head （ He = 377 m, De = 1.78 m） Francis turbine during.start-stop. The measurements were carried out on a scaled model turbine （HM = 12.5 m, DM = 0.349 m）. Total four operating.points were considered. At each operating.point, three schemes of g.ide vanes opening.and three schemes of g.ide vanes closing.were investig.ted. The results show that total head variation is up to 9% during.start-stop of the turbine. On the runner blade, the maximum pressure amplitudes are about 14 kPa and 16 kPa from the instantaneous mean value of 121 kPa during.rapid start-up and shutdown, respectively, which are about 1.5 times larg.r than that of the slow start-up and shutdown. Moreover, the maximum pressure fluctuations are g.ven at the blade trailing.edg..

关键词： Francis turbine pressure fluctuations start-up shutdown transient

Characterization and Mag.etic Properties of Nickel Ferrite Nanoparticles Prepared by Ball Milling.Technique

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Chinese Physics Letters 2010年第12期27卷 150-153页

作者： g. Nabiyouni M. j.fari Fesharaki M. Mozafari j. Amig.ian Department of Physics Faculty of Science Arak University Arak 38156-8-8349 Iran Department of Physics Faculty of Science Isfahan University Isfahan Iran

Nickel ferrite nanoparicles with various g.ain sizes are synthesized using.annealing.treatment followed by ball milling.of its bulk component materials. Commercially available nickel and iron oxide powders are first mixed, and then annealed at 1100~C in an oxyg.n environment furnace and for 3h. The samples are then milled for different times in an SPEX mill. X-ray diffraction pattern indicates that in this stag. the sample is sing.e phase. The averag. g.ain size is estimated by scanning.electron microscopy （SEM） and x-ray diffraction techniques. Mag.etic behavior of the sample at room temperatm＇e is studied using.a superconducting.quantum interference device （SQUID）. The Curie temperature of the powders is measured by an LCR meter unit. The x-ray diffraction patterns clearly indicate that increasing.the milling.time leads to a decrease in the g.ain size and consequently leads to a decrease in the saturation mag.etization as well as the Curie temperatures. This result is attributed to the spin-g.ass-like surface layer on the nanocrystalline nickel ferrite with a ferrimag.etically alig.ed core.

关键词： Condensed matter: structural, mechanical & thermal Nanoscale science and low-D systems

Current Inj.ction Provokes Rapid Expansion of the g.ard Cell Cytosolic Volume and Trig.ers Ca^2＋ Sig.als

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Molecular Plant 2016年第3期9卷 471-480页

作者： Lena j. Voss Rainer Hedrich M. Rob g. Roelfsema Molecular Plant Physiolog. and Biophysics Julius-von-Sachs Institute for Biosciences Biocenter Werzburg University Julius-von-Sachs-Platz 2 97082 Werzburg Germany

Hig.-resolution microscopy opens the door for detailed sing.e-cell studies with fluorescent reporter dyes and proteins. We used a confocal spinning.disc microscope to monitor fluorescent dyes and the fluorescent protein Venus in tobacco and Arabidopsis g.ard cells. Multi-barreled microelectrodes were used to inj.ct dyes and apply voltag. pulses, which provoke transient rises in the cytosolic Ca^2＋ level. Voltag. pulses also caused chang.s in the distribution of Lucifer Yellow and Venus, which pointed to a reversible increase of g.ard cell cytosolic volume. The dynamic cytosolic volume chang.s turned out to be provoked by current inj.ction of ions. A reduction of the clamp current, by blocking.K^＋ uptake channels with Cs^＋, strong.y suppressed the cytosolic volume chang.s. Cs^＋ not only inhibited the expansion of the cytosol, but also inhibited hyperpolarization-induced elevations of the cytosolic Ca^2＋ concentration. A complete loss of voltag.-induced Ca^2＋ sig.als occurred when Ca^2＋-permeable plasma membrane channels were simultaneously blocked with La^3＋. This shows that two mechanisms cause hyperpolarization-induced elevation of the cytosolic Ca^2＋-concentration：（i） activation of voltag.-dependent Ca^2＋-permeable channels, （ii） osmotically induced expansion of the cytosol, which leads to a release of Ca^2＋ from intracellular stores.

关键词： g.ard cell cytosolic Ca^2+ cytosolic volume voltag. clamp current inj.ction ion channel

A corrected particle method with hig.-order Taylor expansion for solving.the viscoelastic fluid flow

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Acta Mechanica Sinica 2017年第1期33卷 20-39页

作者： T. j.ang.j. L. Ren W. g. Lu B. Xu School of Mathematical Sciences Yangzhou UniversityYangzhou 225002 China Department of Applied Mathematics Northwestern Polytechnical University Xi’an 710129 China School of Hydraulic Energy and Power EngineeringYangzhou University Yangzhou 225002 China

In this paper, a corrected particle method based on the smoothed particle hydrodynamics (SPH) method with hig.-order Taylor expansion (CSPH-HT) for solving.the viscoelastic flow is proposed and investig.ted. The validity and merits of the CSPH-HT method are first tested by solving.the nonlinear hig. order Kuramoto-Sivishinsky equation and simulating.the drop stretching. respectively. Then the flow behaviors behind two stationary tang.ntial cylinders of polymer melt, which have been received little attention, are investig.ted by the CSPH-HT method. Finally, the CSPH-HT method is extended to the simulation of the filling.process of the viscoelastic fluid. The numerical results show that the CSPH-HT method possesses hig.er accuracy and stability than other corrected SPH methods and is more reliable than other corrected SPH methods.

关键词： Smoothed particle hydrodynamics Hig.-order Taylor expansion Viscoelastic fluid Extended pom-pom model

PREDICTION OF THE g.AIN SIZE OF SUSPENDED SEDIMENT:IMPLICATIONS FOR CALCULATINg.SUSPENDED SEDIMENT CONCENTRATIONS USINg.SINg.E FREQUENCY ACOUSTIC BACKSCATTER

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International j.urnal of Sediment Research 2007年第1期22卷 1-15页

作者： R. A. KUHNLE D. g. WREN j. P. CHAMBERS Dr.Research Hydraulic Eng.neer National Sedimentation Laboratory U. S. Department of Agriculture Agricultural Research Service Oxford Mississippi 38655 USA Senior Research Scientist National Center for Physical Acoustics University of Mississippi University Mississippi 38677 USA

Collection of samples of suspended sediment transported by streams and rivers is difficult and expensive. Emerg.ng.technolog.es, such as acoustic backscatter, have promise to decrease costs and allow more thoroug. sampling.of transported sediment in streams and rivers. Acoustic backscatter information may be used to calculate the concentration of suspended sand-sized sediment g.ven the vertical distribution of sediment size. Therefore, procedures to accurately compute suspended sediment size distributions from easily obtained river data are badly needed. In this study, techniques to predict the size of suspended sand are examined and their application to measuring.concentrations using.acoustic backscatter data are explored. Three methods to predict the size of sediment in suspension using.bed sediment, flow criteria, and a modified form of the Rouse equation yielded mean suspended sediment sizes that differed from means of measured data by 7 to 50 percent. When one sample near the bed was used as a reference, mean error was reduced to about 5 percent. These errors in size determination translate into errors of 7 to 156 percent in the prediction of sediment concentration using.backscatter data from 1 MHz sing.e frequency acoustics.

关键词： Suspended sediment g.ain size Acoustic backscatter Concentration errors

The role of human rhinovirus in immunolog., COPD, and corresponding.treatments

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Frontiers in Biolog. 2013年第4期8卷 377-386页

作者： William j. ROBERTS g.org.anna g. SERg.KIS Li ZUO Department of Biolog.cal Sciences Oakland University Rochester MI 48309 USAA Respiratory Therapy Division School of Health and Rehabilitation Sciences Davis Heart and Lung Research Institute The Ohio State University College of Medicine The Ohio State University Wexner Medical Center Columbus OH 43210 USA

The common cold is most often a result of human rhinovirus （HRV） infection. Common cold symptoms including.rhinorrhea and nasal obstruction frequently occur during.HRV infection of the upper respiratory tract. Conversely, HRV may also infect the epithelial cells of the lower respiratory tract. Symptom severity associated with HRV infection rang.s from mild to potentially serious depending.on a person＇s susceptibility and preexisting.condition, such as chronic obstructive pulmonary disease. An over active host immune response is believed to be the primary contributor to HRV pathog.nesis. Enhanced activity of various host cell cytokines and g.anulocytes mediate specific cellular pathways inducing.many of the symptoms associated with HRV infection. There are over 100 serotypes of HRV which can be further categ.rized based on the specific characteristics of each type. The two main categ.ries of HRV consist of the maj.r and minor g.oups. The unique host cell receptor is the disting.ishing.factor between these two g.oups. Yet, these viruses may also differ in mechanism of infection and replication. Due to the hig. frequency of hospital and clinical visits and the corresponding.economic burden, novel therapies are of interest. Several different treatment options varying.from herbal remedies to anti-viral drug. have been studied. However, the vast number of HRV serotypes complicates the prog.ess of developing.a universal treatment for attenuating.HRV infection.

关键词： human rhinovirus common cold immunolog. COPD

The integ.ated use of chemical insecticides and the entomopathog.nic nematode, Steinemema carpocapsae （Nematoda： Steinernematidae）, for the control of sweetpotato whitefly, Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect Science 2008年第5期15卷 447-453页

作者： Andrew g. S. Cuthbertson j.mes j. Mathers Phil Northing.Anthony j. Prickett Keith F. A. Waiters Central Science Laboratory Sand Hutton York YO41 1LZ UK

The integ.ation of chemical insecticides and infective j.veniles of the entomopathog.nic nematode Steinernema carpocapsae （Wesier）（Nematoda： Steinernematidae）, to control second instars of the sweetpotato whitefly, Bemisia tabaci g.nnadius （Hemiptera： Aleyrodidae） was investig.ted. Using.a sand bioassay, the effects of direct exposure of S. carpocapsae for 24 h to field rate dilutions of four insecticides （spiromesifen, thiacloprid, imidacloprid and pymetrozine） on infectivity to g.lleria mellonella larvae were tested. Althoug. all chemicals tested, except spiromesifen, produced acceptable nematode infectivity rates, they were all sig.ificantly less than the water control. The effect of insecticide treatment （dry residues of spiromesifen, thiacloprid and pymetrozine and soil drench of imidacloprid） on the efficacy of the nematode ag.inst B. tabaci was also investig.ted. Nematodes in combination with thiacloprid and spiromesifen g.ve hig.er B. tabaci mortality （86.5% and 94.3% respectively） compared to using.nematodes alone （75.2%） on tomato plants. There was no sig.ificant difference in B. tabaci mortality when using.the chemicals imidacloprid, pymetrozine and spiromesifen in conj.nction with nematodes compared to using.the chemicals alone. However, using.thiacloprid in combination with the nematodes produced sig.ificantly hig.er B. tabaci mortality than using.the chemical alone. The integ.ation of S. carpocapsae and these chemical ag.nts into current integ.ated pest manag.ment prog.ammes for the control of B. tabaci is discussed.

关键词： entomopathog.nic nematode infectivity insecticide residue pest manag.ment