Bibliografías temáticas / Selective refocusing / Artículos de revistas

Artículos de revistas sobre el tema "Selective refocusing"

Siga este enlace para ver otros tipos de publicaciones sobre el tema: Selective refocusing.
Autor: Grafiati
Publicado: 6 de septiembre de 2023

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 50 mejores artículos de revistas para su investigación sobre el tema "Selective refocusing".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore artículos de revistas sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

1

Doll, Andrin y Gunnar Jeschke. "Double electron–electron resonance with multiple non-selective chirp refocusing". Physical Chemistry Chemical Physics 19, n.º 2 (2017): 1039–53. http://dx.doi.org/10.1039/c6cp07262c.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Blechta, Vratislav y Jan Schraml. "A selective INEPT experiment for the assignment of NMR lines of low-gyromagnetic ratio nuclei through long-range couplings". Collection of Czechoslovak Chemical Communications 56, n.º 2 (1991): 258–61. http://dx.doi.org/10.1135/cccc19910258.

Texto completo
Resumen
A selective variant of the standard INEPT experiment is suggested. The selectivity is achieved by replacing the refocusing proton pulses of the standard INEPT pulse sequence with selective (DANTE) 180° pulses. Since this approach eliminates the undesirable influences of homo- and heteronuclear couplings, the sensitivity of the method is high. In the case of assigning 29Si NMR lines of trimethylsilylated compounds the pulse sequence can be further simplified and a pair of refocusing pulses can be eliminated from the refocusing period. Advantages of the simplified method are demonstrated.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Beguin, L., N. Giraud, J. M. Ouvrard, J. Courtieu y D. Merlet. "Improvements to selective refocusing phased (SERFph) experiments". Journal of Magnetic Resonance 199, n.º 1 (julio de 2009): 41–47. http://dx.doi.org/10.1016/j.jmr.2009.03.012.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Emsley, Lyndon y Geoffrey Bodenhausen. "Volume-selective NMR spectroscopy with self-refocusing pulses". Journal of Magnetic Resonance (1969) 87, n.º 1 (marzo de 1990): 1–17. http://dx.doi.org/10.1016/0022-2364(90)90081-j.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Herbert Pucheta, José Enrique, Daisy Pitoux, Claire M. Grison, Sylvie Robin, Denis Merlet, David J. Aitken, Nicolas Giraud y Jonathan Farjon. "Pushing the limits of signal resolution to make coupling measurement easier". Chemical Communications 51, n.º 37 (2015): 7939–42. http://dx.doi.org/10.1039/c5cc01305d.

Texto completo
Resumen
Novel band selective decoupled pure shift selective refocusing experiments allowed simplification of the measurement of all δ1H, and JHH couplings with an ultrahigh spectral resolution in peptides.
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Moore, Jay, Marcin Jankiewicz, Adam W. Anderson y John C. Gore. "Evaluation of non-selective refocusing pulses for 7T MRI". Journal of Magnetic Resonance 214 (enero de 2012): 212–20. http://dx.doi.org/10.1016/j.jmr.2011.11.010.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Jie, FENG, WANG Shi-gang, WEI Jian y ZHAO Yan. "Saliency detection combined with selective light field refocusing of camera array". Chinese Optics 14, n.º 3 (2021): 587–95. http://dx.doi.org/10.37188/co.2020-0165.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Bikash, Uday y N. Suryaprakash. "Enantiomeric Discrimination by Double Quantum Excited Selective Refocusing (DQ-SERF) Experiment". Journal of Physical Chemistry B 111, n.º 43 (noviembre de 2007): 12403–10. http://dx.doi.org/10.1021/jp074873s.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Marshman, Margaret F., Ian M. Brereton, Stephen E. Rose, Anthony J. O'Connor y David M. Doddrell. "Application of self-refocusing band selective RF pulses for spectroscopic localization". Magnetic Resonance in Medicine 25, n.º 2 (junio de 1992): 248–59. http://dx.doi.org/10.1002/mrm.1910250204.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Wang, Yingqian, Jungang Yang, Yulan Guo, Chao Xiao y Wei An. "Selective Light Field Refocusing for Camera Arrays Using Bokeh Rendering and Superresolution". IEEE Signal Processing Letters 26, n.º 1 (enero de 2019): 204–8. http://dx.doi.org/10.1109/lsp.2018.2885213.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
11

Wehrli, F. W., A. Shimakawa, G. T. Gullberg y J. R. MacFall. "Time-of-flight MR flow imaging: selective saturation recovery with gradient refocusing." Radiology 160, n.º 3 (septiembre de 1986): 781–85. http://dx.doi.org/10.1148/radiology.160.3.3526407.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
12

Janich, Martin A., Mary A. McLean, Ralph Noeske, Steffen J. Glaser y Rolf F. Schulte. "Slice-selective broadband refocusing pulses for the robust generation of crushed spin-echoes". Journal of Magnetic Resonance 223 (octubre de 2012): 129–37. http://dx.doi.org/10.1016/j.jmr.2012.08.003.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
13

Choi, Changho, Nicholas J. Coupland, Paramjit P. Bhardwaj, Nikolai Malykhin, Dan Gheorghiu y Peter S. Allen. "Measurement of brain glutamate and glutamine by spectrally-selective refocusing at 3 tesla". Magnetic Resonance in Medicine 55, n.º 5 (2006): 997–1005. http://dx.doi.org/10.1002/mrm.20875.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
14

Petrovic, Andreas, Eva Scheurer y Rudolf Stollberger. "Closed-form solution for T2mapping with nonideal refocusing of slice selective CPMG sequences". Magnetic Resonance in Medicine 73, n.º 2 (13 de marzo de 2014): 818–27. http://dx.doi.org/10.1002/mrm.25170.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
15

Zeng, Qing, Chaoqun Zhan, Xi Dong, Jinyong Chen, Zhong Chen y Yanqin Lin. "Unambiguous and accurate measurement of scalar coupling constants through a selective refocusing NMR experiment". Analytica Chimica Acta 1159 (mayo de 2021): 338429. http://dx.doi.org/10.1016/j.aca.2021.338429.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
16

Emsley, Lyndon y Geoffrey Bodenhausen. "Self-refocusing effect of 270° Gaussian pulses. Applications to selective two-dimensional exchange spectroscopy". Journal of Magnetic Resonance (1969) 82, n.º 1 (marzo de 1989): 211–21. http://dx.doi.org/10.1016/0022-2364(89)90185-6.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
17

Crouch, Ronald, Robert D. Boyer, Ross Johnson y Krish Krishnamurthy. "Broadband and band-selective IMPRESS–gHMBC: compensation of refocusing inefficiency with synchronized inversion sweep". Magnetic Resonance in Chemistry 42, n.º 3 (12 de febrero de 2004): 301–7. http://dx.doi.org/10.1002/mrc.1316.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
18

Mccoy, M. A. "Selective Refocusing of Cβ Scalar Coupling During Indirect Evolution of Heteronuclear Single-Quantum Carbon Coherences". Journal of Magnetic Resonance, Series B 107, n.º 3 (junio de 1995): 270–73. http://dx.doi.org/10.1006/jmrb.1995.1088.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
19

Scheenen, Tom W. J., Arend Heerschap y Dennis W. J. Klomp. "Towards 1H-MRSI of the human brain at 7T with slice-selective adiabatic refocusing pulses". Magnetic Resonance Materials in Physics, Biology and Medicine 21, n.º 1-2 (22 de enero de 2008): 95–101. http://dx.doi.org/10.1007/s10334-007-0094-y.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
20

Lim, Eun Ji, Chul-Ho Sohn, Taehoon Shin y Jaeseok Park. "FID-calibrated simultaneous multi-slice fast spin echo with long trains of hard pulses". Physics in Medicine & Biology 67, n.º 3 (27 de enero de 2022): 035002. http://dx.doi.org/10.1088/1361-6560/ac499a.

Texto completo
Resumen
Abstract Objective. To develop a novel, free-induction-decay (FID)-calibrated single-shot simultaneous multi-slice fast spin echo (SMS-FSE) with very long hard pulse trains for high encoding efficiency and low energy deposition. Approach. The proposed single-shot SMS-FSE employs a mixed pulse configuration in which a long excitation pulse that is spatially multi-band (MB) selective is used in conjunction with short spatially nonselective refocusing pulses. To alleviate energy deposition to tissues while reducing signal modulation along the echo train, variable low flip angles with signal prescription are utilized in the refocusing pulse train. A time-efficient FID calibration and correction method is introduced before aliased voxels in the slice direction are resolved. Simulations and experiments are performed to demonstrate the feasibility of the proposed method as an alternative to conventional HASTE for generating T 2-weighted images. Main results. Compared with conventional HASTE, the proposed method enhances imaging speed effectively by an MB factor up to 5 without apparent loss of image contrast while successfully eliminating FID artifacts. Significance. We successfully demonstrated the feasibility of the proposed method as an encoding- and energy-efficient alternative to conventional HASTE for generation of T 2-weighted contrast.
Los estilos APA, Harvard, Vancouver, ISO, etc.
21

Li, Ying, Benjamin J. Wylie y Chad M. Rienstra. "Selective refocusing pulses in magic-angle spinning NMR: Characterization and applications to multi-dimensional protein spectroscopy". Journal of Magnetic Resonance 179, n.º 2 (abril de 2006): 206–16. http://dx.doi.org/10.1016/j.jmr.2005.12.003.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
22

Gambarota, Giulio, Arnaud Bondon, Marie Le Floch, Robert V. Mulkern y Hervé Saint-Jalmes. "Selective spectral modulation of strongly coupled spins with an echo top refocusing pulse in PRESS sequences". Journal of Magnetic Resonance 228 (marzo de 2013): 76–80. http://dx.doi.org/10.1016/j.jmr.2012.12.014.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
23

Farjon, Jonathan, Denis Merlet, Philippe Lesot y Jacques Courtieu. "Enantiomeric excess measurements in weakly oriented chiral liquid crystal solvents through 2D 1H selective refocusing experiments". Journal of Magnetic Resonance 158, n.º 1-2 (septiembre de 2002): 169–72. http://dx.doi.org/10.1016/s1090-7807(02)00070-8.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
24

Doddrell, David M., Graham J. Galloway, Stephen E. Rose, Peter J. Moulds y Ian M. Brereton. "On the use of a slice-selective 270° self-refocusing Gaussian pulse for magnetic resonance imaging". Magnetic Resonance in Medicine 19, n.º 2 (junio de 1991): 456–60. http://dx.doi.org/10.1002/mrm.1910190237.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
25

Farjon, Jonathan, Jean-Pierre Baltaze, Philippe Lesot, Denis Merlet y Jacques Courtieu. "Heteronuclear selective refocusing 2D NMR experiments for the spectral analysis of enantiomers in chiral oriented solvents". Magnetic Resonance in Chemistry 42, n.º 7 (1 de junio de 2004): 594–99. http://dx.doi.org/10.1002/mrc.1399.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
26

Garrity, R. R., G. Rimmelzwaan, A. Minassian, W. P. Tsai, G. Lin, J. J. de Jong, J. Goudsmit y P. L. Nara. "Refocusing neutralizing antibody response by targeted dampening of an immunodominant epitope." Journal of Immunology 159, n.º 1 (1 de julio de 1997): 279–89. http://dx.doi.org/10.4049/jimmunol.159.1.279.

Texto completo
Resumen
Abstract Immunodominant epitopes are known to suppress a primary immune response to other antigenic determinants by a number of mechanisms. Many pathogens have used this strategy to subvert the immune response and may be a mechanism responsible for limited vaccine efficacies. HIV-1 vaccine efficacy appears to be complicated similarly by a limited, immunodominant, isolate-restricted immune response generally directed toward determinants in the third variable domain (V3) of the major envelope glycoprotein, gp120. To overcome this problem, we have investigated an approach based on masking the V3 domain through addition of N-linked carbohydrate and reduction in net positive charge. N-linked modified gp120s were expressed by recombinant vaccinia virus and used to immunize guinea pigs by infection and protein boosting. This modification resulted in variable site-specific glycosylation and antigenic dampening, without loss of gp120/CD4 binding or virus neutralization. Most importantly, V3 epitope dampening shifted the dominant type-specific neutralizing Ab response away from V3 to an epitope in the first variable domain (V1) of gp120. Interestingly, in the presence of V3 dampening V1 changes from an immunodominant non-neutralizing epitope to a primary neutralizing epitope with broader neutralizing properties. In addition, Ab responses were also observed to conserved domains in C1 and C5. These results suggest that selective epitope dampening can lead to qualitative shifts in the immune response resulting in second order neutralizing responses that may prove useful in the fine manipulation of the immune response and in the development of more broadly protective vaccines and therapeutic strategies.
Los estilos APA, Harvard, Vancouver, ISO, etc.
27

Bottomley, Paul A. y Christopher J. Hardy. "Two‐dimensional spatially selective spin inversion and spin‐echo refocusing with a single nuclear magnetic resonance pulse". Journal of Applied Physics 62, n.º 10 (15 de noviembre de 1987): 4284–90. http://dx.doi.org/10.1063/1.339103.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
28

Zeng, Qing, Yanqin Lin y Zhong Chen. "Pushing resolution limits for extracting 1H–1H scalar coupling constants by a resolution-enhanced selective refocusing method". Journal of Chemical Physics 150, n.º 18 (14 de mayo de 2019): 184202. http://dx.doi.org/10.1063/1.5089930.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
29

Shen, Jie F. y John K. Saunders. "A slice-selective adiabatic refocusing pulse made up of two adiabatic inversion pulses. Suppression of unwanted echoes". Journal of Magnetic Resonance (1969) 96, n.º 2 (febrero de 1992): 381–86. http://dx.doi.org/10.1016/0022-2364(92)90091-k.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
30

Santoro, Alessio. "A City of Guardians: Refocusing the Aim and Scope of Aristotle’s Critique of Plato’s Republic". Polis: The Journal for Ancient Greek and Roman Political Thought 36, n.º 2 (28 de junio de 2019): 313–35. http://dx.doi.org/10.1163/20512996-12340212.

Texto completo
Resumen
Abstract In Politics 2.2-5 Aristotle criticises the state described in Plato’s Republic. The general consensus in the secondary literature (in particular after E. Bornemann) is that Aristotle’s critique is unfair and too narrow in scope. Aristotle unjustifiably ignores significant parts of Plato’s Republic and unreasonably assumes that the community of wives, children and property extends to the whole of Kallipolis. Although R. Mayhew’s defence of Aristotle’s criticism has mitigated this negative assessment, the problem has remained unresolved. This paper questions the traditional view and suggests an explanation of Aristotle’s selective reading of Plato’s Republic. Based on what turns out to be a reasonable interpretation of Plato’s text, Aristotle does not extend Plato’s communism to the whole city, but rather reduces Plato’s city to the community of the guardians. As a result, Aristotle’s arguments in fact hit the mark and present Aristotle as a much fairer reader than is usually acknowledged.
Los estilos APA, Harvard, Vancouver, ISO, etc.
31

Lei, Hao y Jeffrey Dunn. "The Effects of Slice-Selective Excitation/Refocusing in Localized Spectral Editing with Gradient-Selected Double-Quantum Coherence Transfer". Journal of Magnetic Resonance 150, n.º 1 (mayo de 2001): 17–25. http://dx.doi.org/10.1006/jmre.2001.2304.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
32

Herbert-Pucheta, José Enrique, Paz Austin-Quiñones, Francisco Rodríguez-González, Cristina Pino-Villar, Guadalupe Flores-Pérez, Santiago José Arguello-Campos y Victor Villalobos Arámbula. "Current trends in ŒNO-NMR based metabolomics". BIO Web of Conferences 56 (2023): 02001. http://dx.doi.org/10.1051/bioconf/20235602001.

Texto completo
Resumen
Present work discusses strengths and limitations of two Nuclear Magnetic Resonance outliers obtained with a water-to-ethanol solvent multi pre saturation acquisition method, recently included in the Compendium of International Methods of Analysis of Wines and Musts, published as OIV-MA-AS316-01, and their accuracy for metabolomics analysis. Furthermore, it is also presented an alternative to produce more discriminant and sensitive NMR data matrices for metabolomics studies, comprising the use of a novel NMR acquisition strategy in wines, the double pulsed-field gradient echo (DPFGE) NMR scheme, with a refocusing band-selective uniform-response pure-phase selective pulse, for a selective excitation of the 5-10 ppm chemical shift range of wine samples, that reveals novel broad aromatic 1H resonances, directly associated to complex polyphenols. Both aromatics and full binned OIV-MA-AS316-01,as well as the selective 5-10 ppm DPFGE NMR outliers were statistically analyzed with diverse non-supervised Principal Component Analysis (PCA) and supervised Partial Least Squares -Discriminant Analysis (PLS-DA), sparse (sPLS-DA) least squares- discriminant analysis, and orthogonal projections to latent structures discriminant analysis (OPLS-DA). Supervised multivariate statistical analysis of DPFGE and aromatics’ binned OIV-MA-AS316-01NMR data have shown their robustness to broadly discriminate geographical origins and narrowly differentiate between different fermentation schemes of wines from identical variety and region.
Los estilos APA, Harvard, Vancouver, ISO, etc.
33

Herbert-Pucheta, José Enrique, José Daniel Lozada-Ramírez, Ana E. Ortega-Regules, Luis Ricardo Hernández y Cecilia Anaya de Parrodi. "Nuclear Magnetic Resonance Metabolomics with Double Pulsed-Field-Gradient Echo and Automatized Solvent Suppression Spectroscopy for Multivariate Data Matrix Applied in Novel Wine and Juice Discriminant Analysis". Molecules 26, n.º 14 (7 de julio de 2021): 4146. http://dx.doi.org/10.3390/molecules26144146.

Texto completo
Resumen
The quality of foods has led researchers to use various analytical methods to determine the amounts of principal food constituents; some of them are the NMR techniques with a multivariate statistical analysis (NMR-MSA). The present work introduces a set of NMR-MSA novelties. First, the use of a double pulsed-field-gradient echo (DPFGE) experiment with a refocusing band-selective uniform response pure-phase selective pulse for the selective excitation of a 5–10-ppm range of wine samples reveals novel broad 1H resonances. Second, an NMR-MSA foodomics approach to discriminate between wine samples produced from the same Cabernet Sauvignon variety fermented with different yeast strains proposed for large-scale alcohol reductions. Third a comparative study between a nonsupervised Principal Component Analysis (PCA), supervised standard partial (PLS-DA), and sparse (sPLS-DA) least squares discriminant analysis, as well as orthogonal projections to a latent structures discriminant analysis (OPLS-DA), for obtaining holistic fingerprints. The MSA discriminated between different Cabernet Sauvignon fermentation schemes and juice varieties (apple, apricot, and orange) or juice authentications (puree, nectar, concentrated, and commercial juice fruit drinks). The new pulse sequence DPFGE demonstrated an enhanced sensitivity in the aromatic zone of wine samples, allowing a better application of different unsupervised and supervised multivariate statistical analysis approaches.
Los estilos APA, Harvard, Vancouver, ISO, etc.
34

Nath, Nilamoni, Bikash Baishya y N. Suryaprakash. "Visualization of enantiomers using natural abundant 13C-filtered single and double quantum selective refocusing experiments: Application to small chiral molecules". Journal of Magnetic Resonance 200, n.º 1 (septiembre de 2009): 101–8. http://dx.doi.org/10.1016/j.jmr.2009.06.011.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
35

Hess, Aaron T., Ovidiu C. Andronesi, M. Dylan Tisdall, A. Gregory Sorensen, André J. W. van der Kouwe y Ernesta M. Meintjes. "Real-time motion and B 0 correction for localized adiabatic selective refocusing (LASER) MRSI using echo planar imaging volumetric navigators". NMR in Biomedicine 25, n.º 2 (28 de julio de 2011): 347–58. http://dx.doi.org/10.1002/nbm.1756.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
36

Emsley, L., J. Kowalewski y G. Bodenhausen. "Measurement of transverse relaxation in coupled spin systems by semi-selective refocusing: Evidence for interference of CSA and dipolar relaxation". Applied Magnetic Resonance 1, n.º 2 (octubre de 1990): 139–47. http://dx.doi.org/10.1007/bf03166151.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
37

Lanzman, R., D. Blondin, P. Schmitt, D. Orzechowski, E. Godehardt, A. Scherer, U. Mödder y P. Kröpil. "Non-Enhanced 3D MR Angiography of the Lower Extremity using ECG-Gated TSE Imaging with Non-Selective Refocusing Pulses – Initial Experience". RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren 182, n.º 10 (23 de abril de 2010): 861–67. http://dx.doi.org/10.1055/s-0029-1245328.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
38

Beguin, Laetitia, Jacques Courtieu, Latifa Ziani y Denis Merlet. "Simplification of the1H NMR spectra of enantiomers dissolved in chiral liquid crystals, combining variable angle sample spinning and selective refocusing experiments". Magnetic Resonance in Chemistry 44, n.º 12 (2006): 1096–101. http://dx.doi.org/10.1002/mrc.1905.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
39

Newling, B., J. A. Derbyshire, T. A. Carpenter, D. Xing y L. D. Hall. "Construction of Multiply Band-Selective Self-Refocusing Pulses for Simultaneous Spin-Echo Multislice Imaging of Fluid Flow, Using Pulsed Field Gradients". Journal of Magnetic Resonance, Series B 108, n.º 3 (septiembre de 1995): 269–73. http://dx.doi.org/10.1006/jmrb.1995.1131.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
40

Hardy, Peter A. y Guang Yue. "Measurement of magnetic resonance T2 for physiological experiments". Journal of Applied Physiology 83, n.º 3 (1 de septiembre de 1997): 904–11. http://dx.doi.org/10.1152/jappl.1997.83.3.904.

Texto completo
Resumen
Hardy, Peter A., and Guang Yue. Measurement of magnetic resonance T2 for physiological experiments. J. Appl. Physiol. 83(3): 904–911, 1997.—The proton transverse relaxation time (T2) of human skeletal muscles has been increasingly used in magnetic resonance imaging experiments to examine muscle physiology and neuromuscular control. However, little attention has been paid to the experimental factors affecting the accuracy or sensitivity of the T2 measurement. We have explored theoretically and experimentally the structure of several magnetic resonance pulse sequences for measuring T2 of the first dorsal interosseous muscle and found that a multiecho imaging technique using non-slice-selective refocusing pulses (MENSS) produces more accurate T2 estimates than multiecho slice-selective (MESS) imaging methods that are commonly used. Using either technique we acquired four 5-mm-thick transverse images of the first dorsal interosseous muscle with a spatial resolution of 0.6 mm within 5 min. The T2 measured by the MENSS method was closer to the true T2 than was the T2 estimated by the MESS method. After a given amount of exercise, the MENSS technique revealed an average 28 ± 10% increase in T2 compared with a 13 ± 3% increase measured with an equivalent MESS technique. We conclude that the MENSS method is a more accurate and sensitive procedure for studying neuromuscular physiology compared with the more commonly used MESS method.
Los estilos APA, Harvard, Vancouver, ISO, etc.
41

Massire, Aurélien, Martijn A. Cloos, Alexandre Vignaud, Denis Le Bihan, Alexis Amadon y Nicolas Boulant. "Design of non-selective refocusing pulses with phase-free rotation axis by gradient ascent pulse engineering algorithm in parallel transmission at 7T". Journal of Magnetic Resonance 230 (mayo de 2013): 76–83. http://dx.doi.org/10.1016/j.jmr.2013.01.005.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
42

Ali, Hamideh Ale, Marcus J. Couch, Ravi Menezes, Andrew J. Evans, Antonio Finelli, Michael A. Jewett y Kartik S. Jhaveri. "Predictive Value of In Vivo MR Spectroscopy With Semilocalization by Adiabatic Selective Refocusing in Differentiating Clear Cell Renal Cell Carcinoma From Other Subtypes". American Journal of Roentgenology 214, n.º 4 (abril de 2020): 817–24. http://dx.doi.org/10.2214/ajr.19.22023.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
43

Krajewski, Piotr y Michel Bardet. "Temperature dependence of proton-proton residual dipolar couplings in adenosine dissolved in charged phospholipid bicelles. Application of a two-dimensional selective refocusing method". Magnetic Resonance in Chemistry 40, n.º 3 (2002): 225–30. http://dx.doi.org/10.1002/mrc.1000.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
44

Wijnen, Jannie P., Jack J. A. van Asten, Dennis W. J. Klomp, Torill E. Sjobakk, Ingrid S. Gribbestad, Tom W. J. Scheenen y Arend Heerschap. "Short echo time1H MRSI of the human brain at 3T with adiabatic slice-selective refocusing pulses; reproducibility and variance in a dual center setting". Journal of Magnetic Resonance Imaging 31, n.º 1 (20 de diciembre de 2009): 61–70. http://dx.doi.org/10.1002/jmri.21999.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
45

Emsley, Lyndon y Geoffrey Bodenhausen. "On the use of a slice-selective 270° self-refocusing Gaussian pulse for magnetic resonance imaging: Comments on the note by D. M. Doddrellet al." Magnetic Resonance in Medicine 19, n.º 2 (junio de 1991): 461–63. http://dx.doi.org/10.1002/mrm.1910190238.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
46

Shen, Xin, Natalie Voets, Sarah Larkin, Nick de Pennington, Puneet Plaha, Richard Stacey, James McCullagh et al. "A Noninvasive Comparison Study between Human Gliomas with IDH1 and IDH2 Mutations by MR Spectroscopy". Metabolites 9, n.º 2 (20 de febrero de 2019): 35. http://dx.doi.org/10.3390/metabo9020035.

Texto completo
Resumen
The oncogenes that are expressed in gliomas reprogram particular pathways of glucose, amino acids, and fatty acid metabolism. Mutations in isocitrate dehydrogenase genes (IDH1/2) in diffuse gliomas are associated with abnormally high levels of 2-hydroxyglutarate (2-HG) levels. The aim of this study was to determine whether metabolic reprogramming associated with IDH mutant gliomas leads to additional 1H MRS-detectable differences between IDH1 and IDH2 mutations, and to identify metabolites correlated with 2-HG. A total of 21 glioma patients (age= 37 ± 11, 13 males) were recruited for magnetic resonance spectroscopy (MRS) using semi-localization by adiabatic selective refocusing pulse sequence at an ultra-high-field (7T). For 20 patients, the tumor mutation subtype was confirmed by immunohistochemistry and DNA sequencing. LCModel analysis was applied for metabolite quantification. A two-sample t-test was used for metabolite comparisons between IDH1 (n = 15) and IDH2 (n = 5) mutant gliomas. The Pearson correlation coefficients between 2-HG and associated metabolites were calculated. A Bonferroni correction was applied for multiple comparison. IDH2 mutant gliomas have a higher level of 2-HG/tCho (total choline=phosphocholine+glycerylphosphorylcholine) (2.48 ± 1.01vs.0.72 ± 0.38, Pc < 0.001) and myo-Inositol/tCho (2.70 ± 0.90 vs. 1.46 ± 0.51, Pc = 0.011) compared to IDH1 mutation gliomas. Associated metabolites, myo-Inositol and glucose+taurine were correlated with 2-HG levels. These results show the improved characterization of the metabolic pathways in IDH1 and IDH2 gliomas for precision medicine.
Los estilos APA, Harvard, Vancouver, ISO, etc.
47

Zimmer, Oliver, Thierry Bigault, Skyler Degenkolb, Christoph Herb, Thomas Neulinger, Nicola Rizzi, Valentina Santoro, Alan Takibayev, Richard Wagner y Luca Zanini. "In-beam superfluid-helium ultracold neutron source for the ESS". Journal of Neutron Research 24, n.º 2 (5 de enero de 2023): 95–110. http://dx.doi.org/10.3233/jnr-220045.

Texto completo
Resumen
This paper discusses design principles and possible performances of an “in-beam” ultracold neutron (UCN) source for the European Spallation Source (ESS). The key components of the proposed neutron delivery system are nested-mirror optics (NMO), which image the bright neutron emission surface of the large liquid-deuterium moderator, studied within the HighNESS project, onto a remotely located superfluid-helium converter. Bandpass supermirrors, with optional polarization capability, enable the selective transport of those neutrons that are most effective for UCN production, exploiting the single-phonon conversion process that is possible for neutrons having wavelengths within a narrow range centered on 8.9 A ˚. NMO are capable of extracting and refocusing neutrons with small transport losses under the large solid angle available at the ESS Large Beam Port (LBP), allowing the converter to be placed far away from the high-radiation area in the ESS shielding bunker, where the source stays accessible for trouble-shooting while facilitating a low-background environment for nearby UCN experiments. Various configurations of the beam and converter are possible, including a large-volume converter – with or without a magnetic reflector – for a large total UCN production rate, or a beam focused onto a small converter for highest possible UCN density. The source performances estimated by first simulations of a baseline version presented in this paper, including a saturated UCN density on the order of 10 5 cm − 3 , motivate further study and the development of NMO beyond the first prototypes that have been recently investigated experimentally.
Los estilos APA, Harvard, Vancouver, ISO, etc.
48

Prener, Martin, Giske Opheim, Zahra Shams, Christian Baastrup Søndergaard, Ulrich Lindberg, Henrik B. W. Larsson, Morten Ziebell, Vibeke Andrée Larsen, Mark Bitsch Vestergaard y Olaf B. Paulson. "Single-Voxel MR Spectroscopy of Gliomas with s-LASER at 7T". Diagnostics 13, n.º 10 (19 de mayo de 2023): 1805. http://dx.doi.org/10.3390/diagnostics13101805.

Texto completo
Resumen
Background and Purpose: Magnetic resonance spectroscopy (MRS)—a method of analysing metabolites in vivo—has been utilized in several studies of brain glioma biomarkers at lower field strengths. At ultra-high field strengths, MRS provides an improved signal-to-noise-ratio and spectral resolution, but 7T studies on patients with gliomas are sparse. The purpose of this exploratory study was to evaluate the potential clinical implication of the use of single-voxel MRS at 7T to assess metabolic information on lesions in a pilot cohort of patients with grade II and III gliomas. Methods: We scanned seven patients and seven healthy controls using the semi-localization by adiabatic-selective refocusing sequence on a Philips Achieva 7T system with a standard dual-transmit head coil. The metabolic ratios were calculated relative to water and total creatine. Additionally, 2-hydroxyglutarate (2-HG) MRS was carried out in four of the patients, and the 2-HG concentration was calculated relative to water. Results: When comparing the tumour data to control regions in both patients and healthy controls, we found that the choline/creatine and myo-inositol/creatine ratios were significantly increased and that the N-acetylaspartate/creatine and the neurotransmitter glutamate/creatine ratios were significantly decreased. The N-acetylaspartate/water and glutamate/water ratios were also significantly decreased. The lactate/water and lactate/creatine ratios showed increases, although not significant. The GABA/water ratio was significantly decreased, but the GABA/creatine ratio was not. MRS spectra showed the presence of 2-HG in three of the four patients studied. Three of the patients, including the MRS 2-HG-negative patient, were operated on, and all of them had the IDH mutation. Conclusion: Our findings were consistent with the existing literature on 3T and 7T MRS.
Los estilos APA, Harvard, Vancouver, ISO, etc.
49

Okada, Tomohisa, Hideto Kuribayashi, Lana G. Kaiser, Yuta Urushibata, Nouha Salibi, Ravi Teja Seethamraju, Sinyeob Ahn, Dinh Ha Duy Thuy, Koji Fujimoto y Tadashi Isa. "Repeatability of proton magnetic resonance spectroscopy of the brain at 7 T: effect of scan time on semi-localized by adiabatic selective refocusing and short-echo time stimulated echo acquisition mode scans and their comparison". Quantitative Imaging in Medicine and Surgery 11, n.º 1 (enero de 2021): 9–20. http://dx.doi.org/10.21037/qims-20-517.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
50

PAPİLA, İbrahim, Selçuk PAKER y Mesut KARTAL. "AN INTEGRATED METHOD FOR REFOCUSING OF MOVING TARGETS IN SPOTLIGHT SAR". AURUM Journal of Engineering Systems and Architecture 7, n.º 1 (30 de junio de 2023): 41–53. http://dx.doi.org/10.53600/ajesa.1321178.

Texto completo
Resumen
A new target-refocusing technique based-on re-centering phase computation of previously recorded moving target raw data is implemented to the Spotlight SAR data in order to obtain refocused moving targets. The technique is tested on the integrated simulated data; background real spotlight SAR Raw data with the synthetically generated data domes of civilian moving targets. First Polar format Algorithm is applied to detect and estimate the speed of ground-moving targets on the integrated raw data. At the next step, re-organize the integrated raw data by selecting and arranging target focusing center with a new technique based on re-centering phase computation to each moving target speed. At the third step re-organize the raw data by re-centering the phase computation to each moving target location. Finally, Polar Format Algorithm is applied to each reorganized raw data to obtain highly focused moving targets individually
Los estilos APA, Harvard, Vancouver, ISO, etc.
Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!

Pasar a la bibliografía