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Journal articles on the topic 'Excitation volume'

Author: Grafiati

Published: 4 June 2021

Last updated: 11 February 2022

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1

Steendijk, P., E. T. Van der Velde, and J. Baan. "Left ventricular stroke volume by single and dual excitation of conductance catheter in dogs." American Journal of Physiology-Heart and Circulatory Physiology 264, no. 6 (June 1, 1993): H2198—H2207. http://dx.doi.org/10.1152/ajpheart.1993.264.6.h2198.

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The conductance method employs a multielectrode catheter to measure intracavitary electric conductance from which left ventricular volume is estimated. A dual-excitation method introduced by us uses a more homogeneous electric field and thereby should enable more accurate volume estimation. In six anesthetized open-chest dogs we compared stroke volume obtained from electromagnetic flow probes with the conventional single-excitation method and with the new dual-excitation conductance method. Caval occlusion and left atrial hemorrhage were used to obtain a wide range of stroke volumes. The slope of the relation between stroke volume calculated from the flow probes and from the conductance catheter increased significantly (P < 0.001) from 0.635 with single excitation to 0.835 with dual excitation, but the interanimal variability was not reduced. The linearity of the relation was substantially improved.

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2

FRANZONE, PIERO COLLI, LUCIANO GUERRI, and BRUNO TACCARDI. "Spread of Excitation in a Myocardial Volume:." Journal of Cardiovascular Electrophysiology 4, no. 2 (April 1993): 144–60. http://dx.doi.org/10.1111/j.1540-8167.1993.tb01219.x.

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3

Jensen, Dye J., Jean L. Delayre, and Ponnada A. Narayana. "Localized T1 measurements using volume-selective excitation." Journal of Magnetic Resonance (1969) 69, no. 3 (October 1986): 552–58. http://dx.doi.org/10.1016/0022-2364(86)90175-7.

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4

SELG, M., M. KINK, R. KINK, J. MAKSIMOV, and I. MARTINSON. "TEMPERATURE DEPENDENCE OF LASER-INDUCED HOT LUMINESCENCE OF SELF-TRAPPED EXCITONS IN SOLID XENON." Surface Review and Letters 09, no. 01 (February 2002): 609–13. http://dx.doi.org/10.1142/s0218625x02002713.

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Hot luminescence of self-trapped excitons in solid xenon has been investigated in a wide temperature range (from LHeT to 100 K), using X-ray and two-photon excimer laser (ArF and KrF) excitation. Hot luminescence of bulk Xe crystals of volume 2 cm 3 appears to be very sensitive to both the temperature and the quality of the samples, while its highest intensity has been registered under KrF laser excitation. The experimental results are in good accordance with a recent nonperturbative quantum relaxation theory of strong local vibrational excitations.

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5

Ediger, M. D., and M. D. Fayer. "Electronic excitation transport in disordered infinite volume systems." International Reviews in Physical Chemistry 4, no. 3 (January 1985): 207–35. http://dx.doi.org/10.1080/01442358509353360.

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6

Aoki, Kohei, Atsushi Okamoto, Yuta Wakayama, Akihisa Tomita, and Satoshi Honma. "Selective multimode excitation using volume holographic mode multiplexer." Optics Letters 38, no. 5 (February 28, 2013): 769. http://dx.doi.org/10.1364/ol.38.000769.

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7

Fiebig, Wiesław. "Influence of the Inter Teeth Volumes on the Noise Generation in External Gear Pumps." Archives of Acoustics 39, no. 2 (March 1, 2015): 261–66. http://dx.doi.org/10.2478/aoa-2014-0030.

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Abstract The paper shows the new method for noise reduction in external gear pumps based on the analysis of the pressure in inter teeth volumes. The simulation model and measurement results of pressure changes in the inter teeth volume has been presented. Based on simulation results an additional volume has been obtained, which is connected to the inter teeth volume (decompression filter volume). Due this additional volume the build down processes in the pump are longer and the pressure overdue in the inter teeth volumes are smaller. This leads to the reduction of the dynamical excitation forces inside the pump and noise, especially in the higher frequency rangeI.

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8

White, John, Victoria Centonze, David Wokosin, and William Mohler. "Using Multiphoton Microscopy for the Study of Embryogenesis." Microscopy and Microanalysis 3, S2 (August 1997): 307–8. http://dx.doi.org/10.1017/s1431927600008424.

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Multiphoton fluorescence excitation imaging is an optical sectioning technique for fluorescence microscopy. At very high photon densities, two or more photons may coordinately excite an energy transition in a fluorophore that corresponds to the sum of the energies of the individual photons. by this means, a fluorophore may be excited by a wavelength that is considerably longer than its single photon excitation wavelength. Ultra-fast pulsed (femtosecond) lasers can produce the peak power densities in the focal volume of an objective lens needed to provide sufficient 2- or 3- photon excitation events for imaging. The use of short-pulse lasers provides the high peak powers necessary for imaging yet with modest mean power levels that do not thermally damage biological specimens. Production of multiphoton events depends on the square of photon density for 2-photon excitation and the cube of photon density for 3-photon excitation. The power density therefore rapidly falls off away from the focal volume of an objective lens, thereby confining fluorescence excitation to the focal volume.

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9

Danton, Mark H. D., Gerald F. Greil, John G. Byrne, Michael Hsin, Lawrence Cohn, and Stephan E. Maier. "Right ventricular volume measurement by conductance catheter." American Journal of Physiology-Heart and Circulatory Physiology 285, no. 4 (October 2003): H1774—H1785. http://dx.doi.org/10.1152/ajpheart.00048.2003.

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Continuous ventricular volume measurement by the conductance method assumes a homogeneous electrical field dispersed throughout and contained within the ventricle. Because of dense trabeculation and complex geometry, right ventricular (RV) volume description by this method may be seriously compromised. This study sought to determine the accuracy and limitations of RV volume measurement by conductance, with magnetic resonance (MR) imaging (MRI) used as a reference, in the porcine RV. Anesthetized pigs ( n = 5, 45–55 kg) were placed in a 1.5-T magnet, and ECG-gated transverse MR images (5-mm slices) were acquired during the complete cardiac cycle. RV cavity volumes were subsequently determined by Simpson's technique. Animals were then instrumented with an RV conductance catheter and an ultrasonic pulmonary artery flow probe. Conductance catheter signals were recorded using single- and dual-field (SF and DF) excitation, and the saline-dilution technique was used to correct volumes for parallel conductance. The gain factor (α) was calculated as the ratio of conductance- to MRI-derived stroke volume (αSV). Variation of α during the cardiac cycle was computed by comparing RV conductance volumes with 1) MRI volumes at isochronal time points within the cardiac cycle [α( t)] and 2) the pulmonary flow integral during ejection. After calibration, the conductance-MRI volume relation was modeled linearly with good correlation [ r = 0.96 (SF) and r = 0.94 (DF)], close to the line of identity. Individual conductance-MRI plots displayed a slight curvilinear relation that was concave toward the MRI axis. Consistent with this finding, α( t) varied significantly during the cardiac cycle (0.49 and 0.39 by SF for end systole and end diastole, respectively, P = 0.011). DF excitation resulted in improved volume measurement [αSV = 0.41 (SF) and 0.96 (DF)], with less variation in α( t) (1.0 and 0.92 by DF for end systole and end diastole, respectively, P = 0.66). These results indicate that, with calibration, the conductance method can measure absolute RV volume under steady-state conditions. However, the curvilinearity and α( t) variation would indicate the potential for nonlinearity when RV volumes are varied over a wider range.

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10

Zhou, Kun, Jian Tian, Qiushi Zhang, Xiangxi Meng, Kun Yang, and Qiushi Ren. "Simulation and quantitative analysis of fluorescence intensity distribution based on the Monte Carlo method." Journal of Innovative Optical Health Sciences 08, no. 06 (October 27, 2015): 1550038. http://dx.doi.org/10.1142/s1793545815500388.

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The Monte Carlo method is a versatile simulation algorithm to model the propagation of photons inside the biological tissues. It has been applied to the reconstruction of the fluorescence molecular tomography (FMT). However, such method suffers from low computational efficiency, and the time consumption is not desirable. One way to solve this problem is to introduce a priori knowledge which will facilitate iterative convergence. We presented an in vivo simulation environment for fluorescence molecular tomography (ISEFMT) using the Monte Carlo method to simulate the photon distribution of fluorescent objects and their sectional view in any direction quantitatively. A series of simulation experiments were carried out on different phantoms each with two fluorescent volumes to investigate the relationship among fluorescence intensity distribution and the excitation photon number, the locations and sizes of the fluorescence volumes, and the anisotropy coefficient. A significant principle was discovered, that along the direction of the excitation light, the fluorescent volume near the excitation point will provide shelter effect so that the energy of the fluorescent volume farther away from the excitation point is relatively lower. Through quantitative analysis, it was discovered that both the photon energy distribution on every cross section and the fluorescence intensity distributed in the two volumes exhibit exponential relationships. The two maximum positions in this distribution correspond to the centers of fluorescent volumes. Finally, we also explored the effect of the phantom coefficients on the exponential rule, and found out that the exponential rule still exists, only the coefficient of the exponential rule changed. Such results can be utilized in locating the positions of multiple fluorescent volumes in complicated FMT reconstruction involving multiple fluorescent volumes. Thus, a priori knowledge can be generalized, which would accelerate the reconstruction of FMT and even other images.

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11

Luo, Suichu, John R. Dunlap, and David C. Joy. "Modulation electron energy loss spectroscopy and its application of quantitative analysis." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 454–55. http://dx.doi.org/10.1017/s0424820100148101.

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Electron energy loss spectroscopy (EELS) gives an inportant insight into the variety of excitations a sample may undergo when irradiated by an electron beam. The focus of this work was to simulate electronic excitations within the energy range from a few to several hundred eV. Our recently developed modulation scheme, combines both convolution and deconvolution techniques, to provide quantitative information about elementary inelastic scattering processes without knowledge of sample parameters such as thickness or optical constants.In the low energy loss region of the spectrum the primary excitation mechanisms include interband transitions, and surface and bulk plasmons. In general these individual excitation events overlap in the spectrum. A FFT convolution procedure was developed where the basic inelastic processes may be represented by the dielectric theory . The dielectric function ε is used to describe both single excitations and collective excitations, where Here ωp2=4πNe2/m is the bulk plasmon frequency, N is number of free electrons per unit volume, e and m are the charge and mass of the electron respectively and ω0 is a constant which is finite for a bound state but zero for a free electron.

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12

Moore, Jay, Marcin Jankiewicz, Huairen Zeng, Adam W. Anderson, and John C. Gore. "Composite RF pulses for -insensitive volume excitation at 7Tesla." Journal of Magnetic Resonance 205, no. 1 (July 2010): 50–62. http://dx.doi.org/10.1016/j.jmr.2010.04.002.

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13

Jung, W. I., and O. Lutz. "Volume Selective NMR Spectroscopy by Coded Slice Excitation (CODEX)." Zeitschrift für Naturforschung A 43, no. 11 (November 1, 1988): 909–13. http://dx.doi.org/10.1515/zna-1988-1101.

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Abstract A method for volume selective nuclear magnetic resonance spectroscopy has been developed and implemented on an 1.5 T whole body imager for in vivo investigations. Four single experiments produce different magnetizations in the same slice, and a special subtract scheme yields the signal of only the volume of interest, which is accurately defined. The resolution of the spectra and the stability of the method have been verified with a water phantom containing acetone, ethanol, methanol, and oil vessels.

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14

Shen, Che-Chou, Shin-Yuan Su, Chih-Hao Cheng, and Chih-Kuang Yeh. "Dual-high-frequency ultrasound excitation on microbubble destruction volume." Ultrasonics 50, no. 7 (June 2010): 698–703. http://dx.doi.org/10.1016/j.ultras.2010.02.005.

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15

van der Graaf, A. W. Maurits, Pranav Bhagirath, Vincent J. H. M. van Driel, Hemanth Ramanna, Jacques de Hooge, Natasja M. S. de Groot, and Marco J. W. Götte. "Computing Volume Potentials for Noninvasive Imaging of Cardiac Excitation." Annals of Noninvasive Electrocardiology 20, no. 2 (July 17, 2014): 132–39. http://dx.doi.org/10.1111/anec.12183.

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16

Müller, S., W. P. Aue, and J. Seelig. "Practical aspects of volume-selective excitation (VSE). Compensation sequences." Journal of Magnetic Resonance (1969) 65, no. 2 (November 1985): 332–38. http://dx.doi.org/10.1016/0022-2364(85)90014-9.

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17

Soini, E., N. J. Meltola, A. E. Soini, J. Soukka, J. T. Soini, and P. E. Hänninen. "Two-photon fluorescence excitation in detection of biomolecules." Biochemical Society Transactions 28, no. 2 (February 1, 2000): 70–74. http://dx.doi.org/10.1042/bst0280070.

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Two-photon fluorescence excitation has been found to be a very powerful method for enhancing the sensitivity and resolution in far-field light microscopy. Two-photon fluorescence excitation also provides a substantially background-free detection on the single-molecule level. It allows direct monitoring of formation of labelled bio-molecule complexes in solution. Two-photon excitation is created when, by focusing an intensive light source, the density of photons per unit volume and per unit time becomes high enough for two photons to be absorbed into the same chromophore. In this case, the absorbed energy is the sum of the energies of the two photons. In two-photon excitation, dye molecules are excited only when both photons are absorbed simultaneously. The probability of absorption of two photons is equal to the product of probability distributions of absorption of the single photons. The emission of two photons is thus a quadratic process with respect to illumination intensity. Thus in two-photon excitation, only the fluorescence that is formed in the clearly restricted three-dimensional vicinity of the focal point is excited. We have developed an assay concept that is able to distinguish optically between the signal emitted from a microparticle in the focal point of the laser beam, and the signal emitted from the surrounding free labelled reagent. Moreover, the free labels outside the focal volume do not contribute any significant signal. This means that the assay is separation-free. The method based on two-photon fluorescence excitation makes possible fast single-step and separation-free immunoassays, for example, for whole blood samples. Since the method allows a separation-free assay in very small volumes, the method is very useful for high-throughput screening assays. Consequently we believe that two-photon fluorescence excitation will make a remarkable impact as a research tool and a routine method in many fields of analysis.

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18

Georges, Joseph. "Continuous-Wave-Laser versus Pulsed-Laser Excitation for Crossed-Beam Photothermal Detection in Small Volume Applications: Comparative Features." Applied Spectroscopy 59, no. 9 (September 2005): 1103–8. http://dx.doi.org/10.1366/0003702055012645.

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Crossed-beam thermal lens spectrometry can be implemented using continuous-wave- (cw) laser or pulsed-laser excitation. In both cases, the signal depends on the position of the sample with respect to the probe beam waist, the size of the excitation beam, the beam-size ratio into the sample, and the power or energy of the excitation beam. However, due to differences in the rate of formation and relaxation of the thermal lens, both methods exhibit distinct key features. Optimization of the experimental setup and understanding the thermal lens signal are more complicated under cw-laser excitation than with pulsed-laser excitation. Unlike that observed under pulsed excitation, the effect of the excitation beam waist, of the sample size, and of the flow rate are closely related to the effective size of the thermal element and depend on the chopping frequency. Although the intrinsic sensitivities are almost the same, the performance can significantly differ depending on the chopping frequency or pulse repetition rate, which should be high enough to allow fast data collection and efficient signal averaging.

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19

Tran, Chieu D., and Minren Xu. "Dual-Wavelength Photothermal Refraction Spectrometry for Small-Volume Samples." Applied Spectroscopy 43, no. 6 (August 1989): 1056–61. http://dx.doi.org/10.1366/0003702894203886.

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A novel dual-wavelength photothermal refraction spectrometer that is capable of simultaneously measuring photothermal refraction at two different wavelengths has been developed. In this instrument, the two excitation wavelengths were provided by an argon-ion (488 nm) and a He-Ne (632.8 nm) laser. These two pump beams were sequentially modulated at the same frequency by means of two mechanical choppers. The photothermal refraction signals produced by the sample absorption of these two pump beams were monitored by a probe beam which was derived from the same He-Ne laser by a beamsplitter. Compared to the single-wavelength techniques, this dual-wavelength apparatus has advantages that include its ability to provide fingerprints and identification of the analyte (as the ratio of the two signals at the two different excitation wavelengths) and to simultaneously determine two-component samples. With this apparatus, the detection limit for two-component samples containing oxohydroxy bis-(8-hydroxy quinoline)-vanadium and 1,2-diamino-anthraquinone in methanol with the use of 25-mW excitation beams modulated at 3.4 Hz is estimated to be 10−7 M. This corresponds to the absorbance of 10−6 for a probe volume of 10−11 L.

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20

AUE, WALTER P. "Non-Invasive Localized NMR Spectroscopy in Vivo: Volume Selective Excitation." Annals of the New York Academy of Sciences 508, no. 1 Physiological (November 1987): 360–65. http://dx.doi.org/10.1111/j.1749-6632.1987.tb32917.x.

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21

Jensen, Dye J., Ponnada A. Narayana, and Jean L. Delayre. "Pulse sequence design for volume selective excitation in magnetic resonance." Medical Physics 14, no. 1 (January 1987): 38–42. http://dx.doi.org/10.1118/1.596092.

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22

Widder, E. A., J. F. Case, S. A. Bernstein, S. MacIntyre, M. R. Lowenstine, M. R. Bowlby, and D. P. Cook. "A new large volume bioluminescence bathyphotometer with defined turbulence excitation." Deep Sea Research Part I: Oceanographic Research Papers 40, no. 3 (March 1993): 607–27. http://dx.doi.org/10.1016/0967-0637(93)90148-v.

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23

Yang, G. Z., P. Burger, P. D. Gatehouse, and D. N. Firmin. "Locally focused 3D coronary imaging using volume-selective RF excitation." Magnetic Resonance in Medicine 41, no. 1 (January 1999): 171–78. http://dx.doi.org/10.1002/(sici)1522-2594(199901)41:1<171::aid-mrm24>3.0.co;2-5.

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24

Lakowicz, Joseph R., Ignacy Gryczynski, and Zygmunt Gryczynski. "High Throughput Screening with Multiphoton Excitation." Journal of Biomolecular Screening 4, no. 6 (December 1999): 355–61. http://dx.doi.org/10.1177/108705719900400610.

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Fluorescence detection is extensively used in high throughput screening. In HTS there is a continuous migration toward higher density plates and smaller sample volumes. In the present report we describe the advantages of two-photon or multiphoton excitation for HTS. Multiphoton excitation (MPE) is the simultaneous absorption of two long-wavelength photons to excite the lowest singlet state of the fluorophore. MPE is typically accomplished with short but high-intensity laser pulses, which allows simultaneous absorption of two or more photons. The intensity of the multiphoton-induced fluorescence is proportional to the square, cube, or higher power of the instantneous photon flux. Consequently, two-photon or multiphoton excitation only occurs at the focal point of the incident beam. This property of two-photon excitation allows the excited volume to be very small and to be localized in the center of each well in the HTS plate. We show that two-photon-induced fluorescence of fluorescein can be reliably measured in microwell plates. We also show the use of 6-carboxy fluorescein as a pH probe with two-photon excitation, and measure 4′-6-diamidino-2-phenylindole (DAPI) binding and two-photon-induced fluorescence. In further studies we measure the time-dependent intensity decays of DAPI bound to DNA and of calcium-dependent fluorophores. Finally, we demonstrate the possibility of three-photon excitation of several fluorophores, including indole, in the HTS plate. These results suggest that MPE can be used in high-density multiwell plates.

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25

Liu, Cong, Zhao, and Ma. "Comprehensive Analysis of the Energy Harvesting Performance of a Fe-Ga Based Cantilever Harvester in Free Excitation and Base Excitation Mode." Sensors 19, no. 15 (August 3, 2019): 3412. http://dx.doi.org/10.3390/s19153412.

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Vibration energy harvesting attempts to generate electricity through recycling the discarded vibration energy that is usually lost or dissipated, and represents an alternative to traditional batteries and may even lead to reliable self-powered autonomous electronic devices. Energy harvesting based on magnetostrictive materials, which takes advantage of the coupling characteristics of the Villari effect and the Faraday electromagnetic induction effect, is a recent research field of great interest. Aiming to develop a new type of magnetostrictive energy harvester using Fe-Ga alloy, which is suitable for harvesting the vibration energy from base excitations and free excitations, a Fe-Ga based cantilever harvester was proposed. The energy harvesting performance of the harvester prototype, including its resonance characteristics, open-circuit output voltage-frequency response and amplitude characteristic under base excitation, influence of external resistance, energy harvesting performance under free excitation, the function of pre-magnetization and so on was studied systematically and carefully by experiments. In terms of the volume power density, the harvester prototype without pre-magnetized magnet when in series with the optimal resistor load displays a value of 2.653 mW/cm3. The average conversion efficiency without a pre-magnetic field is about 17.7% when it is in series with a 200 resistance. The energy harvesting and converting capability can therefore be improved greatly once the Fe-Ga beam is highly pre-magnetized. The prototype successfully lit up multi-LEDs and digital display tubes, which validates the sustainable power generation capacity of the fabricated prototype.

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26

Kamleh, Waseem, Derek Leinweber, Zhan-wei Liu, Finn Stokes, Anthony Thomas, Samuel Thomas, and Jia-jun Wu. "Structure of the Nucleon and its Excitations." EPJ Web of Conferences 175 (2018): 06019. http://dx.doi.org/10.1051/epjconf/201817506019.

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The structure of the ground state nucleon and its finite-volume excitations are examined from three different perspectives. Using new techniques to extract the relativistic components of the nucleon wave function, the node structure of both the upper and lower components of the nucleon wave function are illustrated. A non-trivial role for gluonic components is manifest. In the second approach, the parity-expanded variational analysis (PEVA) technique is utilised to isolate states at finite momenta, enabling a novel examination of the electric and magnetic form factors of nucleon excitations. Here the magnetic form factors of low-lying odd-parity nucleons are particularly interesting. Finally, the structure of the nucleon spectrum is examined in a Hamiltonian effective field theory analysis incorporating recent lattice-QCD determinations of low-lying two-particle scattering-state energies in the finite volume. The Roper resonance of Nature is observed to originate from multi-particle coupled-channel interactions while the first radial excitation of the nucleon sits much higher at approximately 1.9 GeV.

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27

Kao, F. J., B. L. Lin, and P. C. Cheng. "Multi-photon Fluorescence Micro-spectroscopy of Plant Tissues." Microscopy and Microanalysis 6, S2 (August 2000): 808–9. http://dx.doi.org/10.1017/s1431927600036539.

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Considering its non-linear nature, two-photon excitation may generate very different spectral response in samples when compared with single photon excitation. It is thus necessary to measure the two-photon spectra of samples, so that the two-photon fluorescence microscopic images can be properly interpreted. Fluorescence spectra obtained from bulk samples may not provide useful information for microscopy. For instance, due to the relatively small contribution to the total fluorescence intensity, a small number of fluorescent particles in a generally fluorescing specimen may escape detection when the spectrum of the specimen as a whole is obtained. Under two-photon excitation, the background noise can be greatly reduced due to the naturally limited excitation volume of focused laser beam. In addition, signals resulted from second harmonic generation (SHG) may be mixed with low level broad-band background autofluorescence which is commonly found in biological specimen. Therefore, measuring fluorescence spectrum from a micro-focused volume is essential for the proper interpretation of multi-photon fluorescence images.

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28

Naito, Eiji, Kohei Nakata, Yukiko Nakano, Yuta Nozue, Shintaro Kimura, Hiroki Sakai, Osamu Yamato, Md Shafiqul Islam, Sadatoshi Maeda, and Hiroaki Kamishina. "Changes of Dorsal Root Ganglion Volume in Dogs with Clinical Signs of Degenerative Myelopathy Detected by Water-Excitation Magnetic Resonance Imaging." Animals 11, no. 6 (June 7, 2021): 1702. http://dx.doi.org/10.3390/ani11061702.

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Canine degenerative myelopathy (DM) is a progressive and fatal neurodegenerative disease. However, a definitive diagnosis of DM can only be achieved by postmortem histopathological examination of the spinal cord. The purpose of this study was to investigate whether the volumetry of DRG using the ability of water-excitation magnetic resonance imaging (MRI) to visualize the DRG in dogs has premortem diagnostic value for DM. Eight dogs with DM, twenty-four dogs with intervertebral disc herniation (IVDH), and eight control dogs were scanned using a 3.0-tesla MRI system, and water-excitation images were obtained to visualize and measure the volume of DRG, normalized by body surface area. The normalized mean DRG volume between each spinal cord segment and mean volume of all DRG between T8 and L2 in the DM group was significantly lower than that in the control and the IVDH groups (P = 0.011, P = 0.002, respectively). There were no correlations within the normalized mean DRG volume between DM stage 1 and stage 4 (rs = 0.312, P = 0.128, respectively). In conclusion, DRG volumetry by the water-excitation MRI provides a non-invasive and quantitative assessment of neurodegeneration in DRG and may have diagnostic potential for DM.

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29

Podhorodecki, A., R. Kudrawiec, M. Nyk, J. Misiewicz, and W. Strek. "Surface- and volume-related excitation of Eu-doped nanocrystalline GaN powders." Optical Materials 31, no. 8 (June 2009): 1252–55. http://dx.doi.org/10.1016/j.optmat.2009.01.008.

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30

Feinberg, David A., Robert Turner, Peter D. Jakab, and Markus Von Kienlin. "Echo-planar imaging with asymmetric gradient modulation and inner-volume excitation." Magnetic Resonance in Medicine 13, no. 1 (January 1990): 162–69. http://dx.doi.org/10.1002/mrm.1910130116.

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31

Oh, C. H., S. K. Hilal, E. X. Wu, and Z. H. Cho. "Phase-Scrambled RF Excitation for 3D Volume-Selective Multislice NMR Imaging." Magnetic Resonance in Medicine 28, no. 2 (December 1992): 290–99. http://dx.doi.org/10.1002/mrm.1910280210.

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32

Andrew, R. D., and B. A. Macvicar. "Imaging cell volume changes and neuronal excitation in the hippocampal slice." Neuroscience 62, no. 2 (September 1994): 371–83. http://dx.doi.org/10.1016/0306-4522(94)90372-7.

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33

Granot, Joseph, Joseph Ben Mair, L. Arrive, Y. Menu, N. Martin, and H. Nahum. "Volume-localized 31P spectroscopy via combined selective presaturation and selective excitation." Journal of Magnetic Resonance (1969) 89, no. 1 (August 1990): 139–45. http://dx.doi.org/10.1016/0022-2364(90)90168-9.

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34

Ueda, Ken-Ichi. "Present status and prospect of KrF laser physics and technology–large volume excitation and UV optics." Laser and Particle Beams 7, no. 3 (August 1989): 375–82. http://dx.doi.org/10.1017/s0263034600007333.

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The physics and technology for e-beam generation, large volume excitation and the ultra-violet optics for high power KrF lasers is presented. The potential, due to the charge deposition, induces a return current in the plasma which balances the e-beam current. The local equilibrium mechanism stabilizes the large volume excitation using intense electron beams. The spatial and temporal characteristics of large aperture diodes are analyzed. Substantial progress in ultra violet optics in Japan has been achieved. The damage threshold of HR dielectric coating increases up to 11 J/cm2 by using low absorption materials.

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35

White, J. G., V. F. Centonze, and D. L. Wokosin. "Imaging Deep Optical Sections with Two-Photon Excitation Fluorescence Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 280–81. http://dx.doi.org/10.1017/s0424820100163861.

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The technique of optical sectioning allows the visualization of a succession of images of parallel planes within a thick specimen with little or no out-of-focus interference. Ultimately, a limit is reached on the depth to which optical sections can be obtained from a given sample. This limit, up to the working distance of the objective, is largely determined by the degree of light scattering encountered by the incident excitation beam as well as the returning emission signal.Confocal imaging was one of the first optical sectioning techniques applied to fluorescence imaging. Two-photon excitation imaging is a recently developed alternative optical sectioning technique for fluorescence imaging where an excitation wavelength of around twice the excitation peak of the fluorophore is used in a laser-scanning microscope. This excitation wavelength produces very little fluorophore excitation in the bulk of the sample, but when the incident photons are confined in space and time sufficient two-photon absorption events can take place to obtain rapid imaging of fluorophores. With high peak powers—obtained with a sub-picosecond pulsed laser source focused by a lens—sufficient photon density can be obtained for easily detectable two-photon events. Thus fluorophore excitation occurs as two photons are absorbed essentially simultaneously, which act effectively as a single photon of twice the energy (half the wavelength). Two-photon events have a quadratic dependence on intensity, and, therefore, decrease rapidly away from the focal volume of the lens. In a raster scanning system, fluorophore excitation is confined to the optical section being viewed as fluorophore away from the lens focal volume is not excited by the long-wavelength illumination.

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36

Woock, John P., Paul B. Yoo, and Warren M. Grill. "Mechanisms of reflex bladder activation by pudendal afferents." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 300, no. 2 (February 2011): R398—R407. http://dx.doi.org/10.1152/ajpregu.00154.2010.

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Activation of pudendal afferents can evoke bladder contraction or relaxation dependent on the frequency of stimulation, but the mechanisms of reflex bladder excitation evoked by pudendal afferent stimulation are unknown. The objective of this study was to determine the contributions of sympathetic and parasympathetic mechanisms to bladder contractions evoked by stimulation of the dorsal nerve of the penis (DNP) in α-chloralose anesthetized adult male cats. Bladder contractions were evoked by DNP stimulation only above a bladder volume threshold equal to 73 ± 12% of the distension-evoked reflex contraction volume threshold. Bilateral hypogastric nerve transection (to eliminate sympathetic innervation of the bladder) or administration of propranolol (a β-adrenergic antagonist) decreased the stimulation-evoked and distension-evoked volume thresholds by −25% to −39%. Neither hypogastric nerve transection nor propranolol affected contraction magnitude, and robust bladder contractions were still evoked by stimulation at volume thresholds below the distension-evoked volume threshold. As well, inhibition of distention-evoked reflex bladder contractions by 10 Hz stimulation of the DNP was preserved following bilateral hypogastric nerve transection. Administration of phentolamine (an α-adrenergic antagonist) increased stimulation-evoked and distension-evoked volume thresholds by 18%, but again, robust contractions were still evoked by stimulation at volumes below the distension-evoked threshold. These results indicate that sympathetic mechanisms contribute to establishing the volume dependence of reflex contractions but are not critical to the excitatory pudendal to bladder reflex. A strong correlation between the magnitude of stimulation-evoked bladder contractions and bladder volume supports that convergence of pelvic afferents and pudendal afferents is responsible for bladder excitation evoked by pudendal afferents. Further, abolition of stimulation-evoked bladder contractions following administration of hexamethonium bromide confirmed that contractions were generated by pelvic efferent activation via the pelvic ganglion. These findings indicate that pudendal afferent stimulation evokes bladder contractions through convergence with pelvic afferents to increase pelvic efferent activity.

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Grzeszczak, A. "The Electron Mean Free Path for Volume Plasmon Excitation in Polycrystalline Beryllium." Zeitschrift für Naturforschung A 42, no. 11 (November 1, 1987): 1372–73. http://dx.doi.org/10.1515/zna-1987-1123.

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Reflection electron energy loss spectra from polycrystalline beryllium for primary electron energies within 100-1000 eV are measured. The peak intensities increase with the primary energy. From this dependence the electron mean free path for volume plasmon excitation in beryllium is evaluated.

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38

Webb, W. W. "How Multiphoton Excitation can Illuminate Biophysics." Microscopy and Microanalysis 3, S2 (August 1997): 299–300. http://dx.doi.org/10.1017/s1431927600008382.

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Multiphoton molecular excitation by the strongly focused femtosecond pulses of infrared light generated as an 80 MHZ pulse train by a mode locked laser provides intrinsic submicron three dimensional spatial resolution of fluorescence excitation and photochemistry for laser scanning fluorescence microscopy. Because two-photon excitation requires simultaneous (∼10-16 seconds), absorption of two-photons focused laser intensities of about 1022 photons/cm2s are required. Since the rate of absorption is proportional to the square of the intensity, excitation is limited to the focal volume and is negligible elsewhere along the double cone of the focused illumination. Therefore, out of focus photodamage and fluorescence are generally negligible and laser scanning fluorescence microscopy with multiphoton excitation is intrinsically three dimensionally resolved with no out of focus background. Since the appropriate wave lengths are infrared for multiphoton excitation of ultraviolet or visible absorbing molecules, out of focus photodamage is eliminated. This allows imaging of useful ultraviolet absorbing indicators, vital DNA stains and autofluorescence in living cells with minimal, but not necessarily negligible, photodamage.

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Powell, Nathaniel J., Albert Jang, Jang-Yeon Park, Julien Valette, Michael Garwood, and Małgorzata Marjańska. "Gradient rotating outer volume excitation (GROOVE): A novel method for single-shot two-dimensional outer volume suppression." Magnetic Resonance in Medicine 73, no. 1 (January 29, 2014): 139–49. http://dx.doi.org/10.1002/mrm.25101.

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Wang, Baoshan, Wei Yang, Songyong Yuan, Shijun Guo, Hongkui Ge, Ping Xu, and Yong Chen. "An experimental study on the excitation of large volume airguns in a small volume body of water." Journal of Geophysics and Engineering 7, no. 4 (September 30, 2010): 388–94. http://dx.doi.org/10.1088/1742-2132/7/4/005.

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Bratt, J. F. "Response of Rotating Reinforced Beams to Shock Excitation." Transactions of the Canadian Society for Mechanical Engineering 11, no. 1 (March 1987): 1–4. http://dx.doi.org/10.1139/tcsme-1987-0001.

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The shock response of rotating cantilever beams composed of alternate plastic and thin reinforcing layers subjected to half-sine pulses at the clamped end was determined based on experiment and verified numerically. The volume fraction and the thickness of reinforcing layers made of steel, aluminum, copper and glass fiber were compared as to influence on the natural frequency. Varying these parameters provides a means of some control of the shock response.

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42

Calkins, H., W. L. Maughan, D. A. Kass, K. Sagawa, and J. H. Levine. "Electrophysiological effect of volume load in isolated canine hearts." American Journal of Physiology-Heart and Circulatory Physiology 256, no. 6 (June 1, 1989): H1697—H1706. http://dx.doi.org/10.1152/ajpheart.1989.256.6.h1697.

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In isolated isovolumic ventricles and in in situ ventricles under nonsteady-state conditions, alterations in load have been shown to affect electrophysiological properties via contraction-excitation feedback. However, the effect of alterations in loading conditions on electrophysiological properties in normal ventricles under physiological loading conditions remains unknown. Furthermore, the arrhythmogenic significance of these load-induced electrophysiological changes is uncertain. We increased end-diastolic volume (27 +/- 4 ml vs. 51 +/- 6 ml) and assessed conduction, refractoriness, ventricular fibrillation thresholds (VFTs), and inducibility of ventricular arrhythmias in 14 isolated blood-perfused ejecting canine ventricles under steady-state conditions. We also examined the effect of increased end-diastolic volume on refractoriness and monophasic action potential (MAP) duration and contour under isovolumic versus ejecting conditions. Under ejecting conditions, increased end-diastolic volume resulted in very small (less than 1.5%) changes in the absolute refractory period (10 mA) and in local activation time but no change in local electrogram duration, overall dispersion of refractoriness, MAP duration or contour, VFT, or inducibility of ventricular arrhythmias. Increased volume loading under isovolumic conditions resulted in a very slight (less than 1%) shortening of MAP duration and refractoriness but had no effect on the MAP contour. These findings provide strong evidence that alterations in volume load are of little electrophysiological or arrhythmogenic importance in normal canine ventricles under physiologically loaded conditions (contraction-excitation feedback, load and arrhythmias, volume load).

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Zhou, Jie, Linyun Xu, Yan Xuan, Yahui Xu, and Guanhua Liu. "Shedding Frequency and Motion of Jujube Fruits in Various Excitation Modes." Transactions of the ASABE 63, no. 4 (2020): 881–89. http://dx.doi.org/10.13031/trans.13776.

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HighlightsThe motion responses of fruits varied greatly in different excitation modes.The excitation modes included horizontal, vertical, and rotational.The shedding frequency of fruits was closely related to their motion response.The optimal excitation mode for Jun jujube is vertical excitation.Abstract. To study the shedding frequency and motion response of Chinese Jun jujube fruits with different excitation modes, a vibration device with three excitation modes (horizontal, vertical, and rotational) was designed. The mature fruits were categorized according to their degree of dryness (fresh, half-dried, and dried). The basic physical parameters (volume, density, pedical-fruit retention force, etc.), shedding frequency, and motion response of the fruits were measured. With horizontal excitation, the response of the fruits was mainly pendulum motion, which increased as the excitation amplitude increased, while the shedding frequency of the fruits correspondingly decreased. However, with vertical excitation, the response of the fruits was mainly a compound motion comprising pendulum and beam-column motions. As the excitation amplitude increased from 5 to 10 mm, the shedding frequency of the fruits decreased dramatically, but further decrease in the shedding frequency was negligible as the excitation amplitude increased to 15 mm. With rotational excitation, the fruits exhibited centrifugal rotation in an approximately horizontal plane, and the amplitude and frequency necessary to achieve dynamic separation were small. It was concluded that the optimal excitation mode for Jun jujube is vertical excitation with an amplitude of 10 mm and frequency between 6 and 10 Hz. Keywords: Excitation modes, Jujube, Motion gesture, Shedding frequency.

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Patil, Bhagyesha S., Priya D. Srinivasan, Ed Atchison, Hongda Zhu, and Juan J. Bravo-Suárez. "Design, modelling, and application of a low void-volume in situ diffuse reflectance spectroscopic reaction cell for transient catalytic studies." Reaction Chemistry & Engineering 4, no. 4 (2019): 667–78. http://dx.doi.org/10.1039/c8re00302e.

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Piston, David W. "Two-Photon Excitation Microscopy in Cellular Biophysics." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 276–77. http://dx.doi.org/10.1017/s0424820100163848.

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Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10 5 limits the average input power to less than 10 mW, only slightly greater than the power normally used in confocal microscopy.Three properties TPEM give this method a tremendous advantage over conventional optical sectioning microscopies for the study of thick samples: 1) The excitation is limited to the focal volume because of the intensity-squared dependence of the two-photon absorption. This inherent localization provides three-dimensional resolution and eliminates background equivalent to an ideal confocal microscope without requiring a confocal spatial filter, whose absence enhances fluorescence collection efficiency. Confinement of excitation to the focal volume also minimizes photobleaching and photo damage - the ultimate limiting factors in fluorescence microscopy of living cells and tissues. 2) The two-photon technique allows imaging of UV fluorophores with conventional visible light optics in both the scanning and imaging systems, because both the red excitation light (~700 nm) and the blue fluorescence (>400 nm) are within the visible spectrum. 3) Red or infrared light is far less damaging to most living cells and tissues than bluer light because fewer biological molecules absorb at the higher wavelengths. Longer wavelength excitation also reduces scattering of the incident light by the specimen, thus allowing more of the input power to reach the focal plane. This relative transparency of biological specimens to 700 nm light permits deeper sectioning, since both absorbance and scattering are reduced.

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Zhang, Qing Hua, and Dong Jie Yan. "Dynamic Response Analysis on Train Liquid Storage Tanks under Impulsive Excitation." Applied Mechanics and Materials 438-439 (October 2013): 1125–28. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.1125.

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Take the typical train liquid storage tank as research object, the vibration modes and the fluid-solid coupling dynamic responses of the tank are analyzed under the impulsive excitation using finite element software ANSYS. The research indicates that the difference of the liquid volume in tank has great influence to the structural stress and strain. With the increasing of the liquid volume, the tank natural frequencies gradually reduced, so the liquid sloshing have great effect on the structural vibration modes. And if the tank is full of the liquid, the stress and total deformation of the tank can be obviously reduced.

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Schneider, Johannes T., Raffi Kalayciyan, Martin Haas, Sarah R. Herrmann, Wolfgang Ruhm, Jürgen Hennig, and Peter Ullmann. "Inner-volume imaging in vivo using three-dimensional parallel spatially selective excitation." Magnetic Resonance in Medicine 69, no. 5 (June 21, 2012): 1367–78. http://dx.doi.org/10.1002/mrm.24381.

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Malik, Shaihan J., and Joseph V. Hajnal. "Phase relaxed localized excitation pulses for inner volume fast spin echo imaging." Magnetic Resonance in Medicine 76, no. 3 (October 9, 2015): 848–61. http://dx.doi.org/10.1002/mrm.25996.

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Oeltzschner, Georg, Nicolaas A. J. Puts, Kimberly L. Chan, Vincent O. Boer, Peter B. Barker, and Richard A. E. Edden. "Dual‐volume excitation and parallel reconstruction for J‐difference‐edited MR spectroscopy." Magnetic Resonance in Medicine 77, no. 1 (November 8, 2016): 16–22. http://dx.doi.org/10.1002/mrm.26536.

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Tingting Shao, Ling Xia, Guisheng Tao, Jieru Chi, Feng Liu, and S. Crozier. "Advanced Three-Dimensional Tailored RF Pulse Design in Volume Selective Parallel Excitation." IEEE Transactions on Medical Imaging 31, no. 5 (May 2012): 997–1007. http://dx.doi.org/10.1109/tmi.2011.2178035.

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