Academic literature on the topic 'High Field MRI'

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Journal articles on the topic "High Field MRI"

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Salvolini, Ugo, and Tommaso Scarabino. "High field MRI." European Journal of Radiology 48, no. 2 (November 2003): 137. http://dx.doi.org/10.1016/j.ejrad.2003.08.011.

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Cunningham, Patricia M., Meng Law, and Mark E. Schweitzer. "High-Field MRI." Orthopedic Clinics of North America 37, no. 3 (July 2006): 321–29. http://dx.doi.org/10.1016/j.ocl.2006.05.002.

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Di Salle, F., F. Esposito, A. Elefante, T. Scarabino, A. Volpicelli, S. Cirillo, R. Elefante, and E. Seifritz. "High field functional MRI." European Journal of Radiology 48, no. 2 (November 2003): 138–45. http://dx.doi.org/10.1016/j.ejrad.2003.08.010.

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Wada, Hitoshi, Masaki Sekino, Hiroyuki Ohsaki, Tatsuhiro Hisatsune, Hiroo Ikehira, and Tsukasa Kiyoshi. "Prospect of High-Field MRI." IEEE Transactions on Applied Superconductivity 20, no. 3 (June 2010): 115–22. http://dx.doi.org/10.1109/tasc.2010.2043939.

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Hespel, Adrien-Maxence, and Robert C. Cole. "Advances in High-Field MRI." Veterinary Clinics of North America: Small Animal Practice 48, no. 1 (January 2018): 11–29. http://dx.doi.org/10.1016/j.cvsm.2017.08.002.

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Doi, et al., Tsukasa. "High Field MRI and Safety." Japanese Journal of Radiological Technology 64, no. 12 (2008): 1491. http://dx.doi.org/10.6009/jjrt.64.1491.

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Coffey, Aaron M., Milton L. Truong, and Eduard Y. Chekmenev. "Low-field MRI can be more sensitive than high-field MRI." Journal of Magnetic Resonance 237 (December 2013): 169–74. http://dx.doi.org/10.1016/j.jmr.2013.10.013.

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Bihan, Denis Le. "Threats to ultra-high-field MRI." Physics World 22, no. 08 (August 2009): 16–17. http://dx.doi.org/10.1088/2058-7058/22/08/23.

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Marzola, Pasquina, Francesco Osculati, and Andrea Sbarbati. "High field MRI in preclinical research." European Journal of Radiology 48, no. 2 (November 2003): 165–70. http://dx.doi.org/10.1016/j.ejrad.2003.08.007.

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Di Salle, F., T. Scarabino, F. Esposito, A. Aragri, O. Santopaolo, A. Elefante, M. Cirillo, S. Cirillo, and R. Elefante. "Functional MRI at High Field Strength." Rivista di Neuroradiologia 17, no. 6 (December 2004): 813–21. http://dx.doi.org/10.1177/197140090401700611.

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Dissertations / Theses on the topic "High Field MRI"

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Jiang, Lei. "Developments in High Field MRI." Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491630.

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The technique of magnetic resonance imaging (MRI) is widely used in both structural and functional imaging. This thesis explores some important developments and applications in high field MRI. The work in this thesis has been undertaken by the author except where indicated by reference. Initially, a purpose-built dynamic functional phantom was devised and used for quality control and testing imaging pulse sequences. A multi-echo GEBPI sequence was assessed and the most efficient ways to combine multiecho data taking account of the effect of bandwidth were explored by using this phantom. Subsequently, this multi-echo sequence was applied for T-i mapping of the whole brain and cerebellum with different slice thicknesses and orientations and used for characterization of the physiological noise in the resting-state brain on 3.0 and 7.0 T systems. Furthermore, physiological noise was also investigated by using a spin echo imaging method. The physiological noise in. gradient and spin echo images was compared. The results support the hypothesis that physiological noise has similar origins as the BOLD signal. Contrast-enhanced MR angiography provides accurate information about vascular structure. The field strength dependence of Rl and R2 relaxivities of a blood pool contrast agent (Gadofosveset) was measured ex vivo in human blood. A computer simulation was performed to investigate quantitatively the performance of contrast-to-noise (CNR) ratio of Gadofosveset-enhanced MRA at different field strengths. Finally, highresolution contrast-enhanced MR angiographic imaging was performed on human subjects at 7.0 T. The initial results demonstrate that, despite posHible technical problems, high quality imaging is feasible at 7.0 T. These H)sults also show that the ultra-high field strength has the potential to offer tllgllificant improvements in CNR and spatial resolution.
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Sulikowska, Aleksandra. "Motion correction in high-field MRI." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33674/.

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The work described in this thesis was conducted at the University of Nottingham in the Sir Peter Mansfield Imaging Centre, between September 2011 and 2014. Subject motion in high- resolution magnetic resonance imaging (MRI) is a major source of image artefacts. It is a very complex problem, due to variety of physical motion types, imaging techniques, or k-space trajectories. Many techniques have been proposed over the years to correct images for motion, all looking for the best practical solution in clinical scanning, which would give cost- effective, robust and high accuracy correction, without decreasing patient comfort or prolonging the scan time. Moreover, if the susceptibility induced field changes due to head rotation are large enough, they will compromise motion correction methods. In this work a method for prospective correction of head motion for MR brain imaging at 7 T was proposed. It would employ innovative NMR tracking devices not presented in literature before. The device presented in this thesis is characterized by a high accuracy of position measurements (0.06 ± 0.04 mm), is considered very practical, and stands the chance to be used in routine imaging in the future. This study also investigated the significance of the field changes induced by the susceptibility in human brain due to small head rotations (±10 deg). The size and location of these field changes were characterized, and then the effects of the changes on the image were simulated. The results have shown that the field shift may be as large as |-18.3| Hz/deg. For standard Gradient Echo sequence at 7 T and a typical head movement, the simulated image distortions were on average equal to 0.5%, and not larger than 15% of the brightest voxel. This is not likely to compromise motion correction, but may be significant in some imaging sequences.
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Mougin, Olivier. "Quantitative methods in high field MRI." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11608/.

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The increased signal-to-noise ratio available at high magnetic field makes possible the acquisition of clinically useful MR images either at higher resolution or for quantitative methods. The work in this thesis is focused on the development of quantitative imaging methods used to overcome difficulties due to high field MRI systems (> 3T). The protocols developed and presented here have been tested on various studies aiming at discriminating tissues based on their NMR properties. The quantities of interest in this thesis are the longitudinal relaxation time T1, as well as the magnetization transfer process, particularly the chemical exchange phenomenon involving amide protons which is highlighted particularly well at 7T under specific conditions. Both quantities (T1 and amide proton transfer) are related to the underlying structure of the tissues in-vivo, especially inside the white matter of the brain. While a standard weighted image at high resolution can provide indices of the extent of the pathology, a robust measure of the NMR properties of brain tissues can detect earlier abnormalities. A method based on a 3D Turbo FLASH readout and measuring reliably the T1 in-vivo for clinical studies at 7T is first presented. The other major part of this thesis presents magnetization transfer and chemical exchange phenomena. First a quantitative method is investigated at 7T, leading to a new model for exchange as well as contrast optimization possibility for imaging. Results using those methods are presented and applied in clinical setting, the main focus being to image reliably the brain of both healthy subjects and Multiple Sclerosis patients to look at myelin structures.
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Wharton, Samuel James. "Susceptibility mapping in high field MRI." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/13074/.

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Phase images of the human brain acquired using gradient echo based Magnetic Resonance Imaging techniques show excellent contrast at 7T. This contrast is attributed to small variations in magnetic susceptibility that perturb the main magnetic field and thus yield a spatial variation of the NMR frequency. The work described in this thesis is primarily concerned with mapping the distribution of magnetic susceptibility within the human brain using these phase images. The main technical challenges of the project were first to extract accurate field maps based on phase data, and then to solve the ill-posed problem of inverting these field maps to reconstruct susceptibility (ϰ) maps. In initial work, simulations of field shifts based on known ϰ -distributions are compared to field maps acquired in vivo to highlight the non-local relationship between measured field offsets and the underlying susceptibility. These simulations were carried out using a recently derived Fourier method. The bulk of the thesis is then devoted to a detailed study of the process of inverting field maps generated from phase data using the Fourier relationship to yield quantitative 3D ϰ -maps. Unfortunately, the inversion problem is ill-posed and requires careful conditioning, either through rotation of the sample being imaged or through regularisation. A simple k-space threshold is introduced to condition the inversion and the preliminary results of applying this method to brain data from healthy subjects and patients with Parkinson's disease and multiple sclerosis are presented. The results suggest that susceptibility mapping is sensitive to iron deposition and could be a useful tool in investigating the progression of neurodegeneratived diseases. Iterative inversion algorithms, which deal with noise more robustly and allow more sophisticated filtering techniques to be employed, are then presented. These powerful regularisation methods are compared to previously described techniques, and are shown to yield high quality whole-brain ϰ -maps.
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Anderson, Christian Edwin. "High-Field Magnetic Resonance Fingerprinting for Molecular MRI." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case152478492457623.

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Gerardin, Emilie. "Morphometry of the human hippocampus from MRI and conventional MRI high field." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00856589.

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The hippocampus is a gray matter structure in the temporal lobe that plays a key role in memory processes and in many diseases (Alzheimer's disease, epilepsy, depression ...).The development of morphometric models is essential for the study of the functional anatomy and structure alterations associated with different pathologies. The objective of this thesis is to develop and validate methods for morphometry of the hippocampus in two contexts: the study of the external shape of the hippocampus from conventional MRI (1.5T or 3T) with millimeter resolution, and the study of its internal structure from 7T MRI with high spatial resolution. These two settings correspond to the two main parts of the thesis.In the first part, we propose a method for the automatic classification of patients from shape descriptors. This method is based on a spherical harmonic decomposition which is combined with a support vector machine classifier (SVM). The method is evaluated in the context of automatic classification of patients with Alzheimer's disease (AD) patients, mild cognitive impairment (MCI) patients and healthy elderly subjects. It is also compared to other approaches and a more comprehensive validation is available in a population of 509 subjects from the ADNI database. Finally, we present another application of morphometry to study structural alterations associated with the syndrome of Gilles de la Tourette.The second part of the thesis is devoted to the morphometry of the internal structure of the hippocampus from MRI at 7 Tesla. Indeed, the internal structure of the hippocampus is rich and complex but inaccessible to conventional MRI. We first propose an atlas of the internal structure of the hippocampus from postmortem data acquired at 9.4T. Then, we propose to model the Ammon's horn and the subiculum as a skeleton and a local measure thickness. To do this, we introduce a variational method using original Hilbert spaces reproducing kernels. The method is validated on the postmortem atlas and evaluated on in vivo data from healthy subjects and patients with epilepsy acquired at 7T.
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Jones, Alexa. "Radio frequency coils for ultra-high field MRI." Thesis, University of Nottingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490979.

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The push toward higher magnetic fields in MRI has consistently thrown up new challenges in hardware development. The recent development of a new generation of ultra-high field scanners for human imaging is no exception. The earch presented in this thesis aims to provide solutions to new technical challenges in radio-frequency probe design. All probe designs were developed for use at 7T on a Philips Acheiva full body scanner.
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Farhat, Sedig. "Radiofrequency coils for ultra-high field body MRI." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/28847/.

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In this thesis, the probes were modelled and constructed at the SPMMRC. All measurements were performed on a 7T Philips scanner. The coils have been successfully evaluated. The dipole, loops, strip line and wrist probes for imaging the pelvis, knee and wrist were tested for clinical use at 7T. Two elements wrist coil can pick up signals from the whole region of interest. The advantage is more uniformity of field of view and better sensitivity. The in vivo MRI images acquired in the wrist showed the two elements provided the good quality images for the human wrist. The second study is microstrip line probe. The current flows over the flat-strip were computed, it showed that a significant increase of current close to the edges. This result agrees with theory. We did not use the strip line coil to image a human body, because the coil generated a high SAR/B1 +2 level in the region of interest. The third study was of a coil of two square loops. One way of achieving decoupling is to use the overlapping technique to decouple the coils in the simulation. It produced high signal-to-noise ratio and provides a large field of view. Finally, the dipole has been developed for in vivo MRI applications. We presented a novel model for determining the length of the PECs required for tuning the dipole at 298 MHz. The efficiency, field of view and homogeneity were improved by adding the flat strip, two strips and array strips dipole. The SAR/B1 +2 generated by the dipoles was much less than produced by the loop coil and strip line coil in the pelvis. The dipoles showed the desired improvement in SNR and homogenous coverage. Coverage goes much further into the pelvis and knee as well.
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De, Vita Enrico. "Development and optimisation of high-field MRI techniques." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408802.

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Shah, Simon Michael. "Magnetisation transfer effects at ultra high field MRI." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39398/.

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Increased signal to noise ratio in ultra high field Magnetic Resonance Imaging (MRI) has allowed the development of quantitative imaging techniques and new contrast mechanisms, such as Chemical Exchange Saturation Transfer (CEST) to be probed. The development of CEST contrast imaging has involved overcoming a number of technical challenges associated with ultra high field MRI. The B1 transmit field was, and still is, a major challenge. Presented in this thesis, the B1 transmit field in regions of low B1 are improved with the use of dielectric pads and a simulation study shows that the overall B1 transmit field homogeneity is significantly improved when multi-transmit slice-selective RF spokes pulse sequences are used. Multiple methods have been developed to quantify the chemical exchange from slow exchanging proton pools seen in CEST contrast imaging. However, magnetisation transfer (MT) from the macromolecular bound pool contaminates current quantification methods, and presented in this thesis is a method whereby the CEST and MT are simultaneously saturated using dual frequency saturation pulses, allowing the CEST contrast in z-spectra to be separated from the MT and to enhance visualisation of the CEST effects. Despite the considerable interest in CEST, only one study has probed the CEST effects in blood, and interestingly high levels of CEST signals can be observed from the superior sagittal sinus. To investigate these effects, z-spectra from ex vivo blood samples considering the effects of oxygenation, haematocrit levels and cell structure were quantified. Quantification shows that the main source of the CEST signals was from the cells within the blood.
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Books on the topic "High Field MRI"

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Salvolini, Ugo, and Tommaso Scarabino, eds. High Field Brain MRI. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7.

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Scarabino, Tommaso, Saverio Pollice, and Teresa Popolizio, eds. High Field Brain MRI. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0.

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D, Stark David, and Hahn Peter F, eds. Hepatobiliary MRI: A text-atlas at mid and high field. St. Louis: Mosby-Year Book, 1992.

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Parker, Philip M. The 2009-2014 world outlook for very high-field MRI systems. [San Diego, Calif.]: Icon Group International, 2008.

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Naidich, Thomas P. Duvernoy’s Atlas of the Human Brain Stem and Cerebellum: High-Field MRI: Surface Anatomy, Internal Structure, Vascularization and 3D Sectional Anatomy. Vienna: Springer Vienna, 2009.

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Bloch, Karin Markenroth, Maxime Guye, and Benedikt A. Poser. Ultra-High Field Neuro MRI. Elsevier Science & Technology, 2023.

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Bloch, Karin Markenroth, Maxime Guye, and Benedikt A. Poser. Ultra-High Field Neuro MRI. Elsevier Science & Technology Books, 2023.

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Scarabino, Tommaso, Saverio Pollice, and Teresa Popolizio. High Field Brain MRI: Use in Clinical Practice. Springer, 2017.

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Scarabino, Tommaso, Saverio Pollice, and Teresa Popolizio. High Field Brain MRI: Use in Clinical Practice. Springer, 2017.

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(Editor), U. Salvolini, and T. Scarabino (Editor), eds. High Field Brain MRI: Use in Clinical Practice. Springer, 2006.

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Book chapters on the topic "High Field MRI"

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Di Salle, F., T. Scarabino, F. Esposito, A. Aragri, O. Santopaolo, A. Elefante, M. Cirillo, S. Cirillo, and R. Elefante. "High-Field Strength Functional MRI." In High Field Brain MRI, 107–16. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7_10.

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Di Costanzo, A., F. Trojsi, T. Popolizio, G. M. Giannatempo, A. Simeone, S. Pollice, D. Catapano, et al. "3.0 T Imaging of Brain Tumours." In High Field Brain MRI, 208–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7_18.

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Tosetti, M., T. Schirmer, V. d’Alesio, A. Di Costanzo, and T. Scarabino. "3.0 T MR Spectroscopy." In High Field Brain MRI, 51–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7_6.

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Scarabino, T., F. Di Salle, F. Esposito, M. Tosetti, M. Armillotta, R. Agati, and U. Salvolini. "3.0 T Diffusion Studies." In High Field Brain MRI, 66–78. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7_7.

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Cherubini, A., G. Luccichenti, F. Fasano, G. E. Hagberg, P. Péran, F. Di Salle, F. Esposito, T. Scarabino, and U. Sabatini. "Nerve Pathways with MR Tractography." In High Field Brain MRI, 79–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-31776-7_8.

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Maiorana, Alberto, and Alessandra Iannelli. "High-Field MRI and Safety: I. Installations." In High Field Brain MRI, 3–6. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0_1.

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Chiacchiaretta, Piero, Armando Tartaro, Simone Salice, and Antonio Ferretti. "ASL 3.0 T Perfusion Studies." In High Field Brain MRI, 133–44. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0_10.

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Cevolani, Daniela, Raffaele Agati, Francesco Di Salle, and Marco Leonardi. "Functional MRI at 3.0 Tesla." In High Field Brain MRI, 145–51. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0_11.

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Popolizio, Teresa, Francesca Di Chio, Rosario Francesco Balzano, and Tommaso Scarabino. "3.0 T Brain MRI: A Pictorial Overview of the Most Interesting Sequences." In High Field Brain MRI, 153–86. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0_12.

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Tartaro, Armando, and Simone Salice. "Setting the Report and Support of the Functional Findings." In High Field Brain MRI, 187–95. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-44174-0_13.

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Conference papers on the topic "High Field MRI"

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van Buchem, M. A., J. van der Grond, M. Versluis, M. J. P. van Osch, W. Teeuwisse, H. Kan, and A. G. Webb. "High field clinical MRI neuroimaging." In 2010 IEEE International Symposium on Biomedical Imaging: From Nano to Macro. IEEE, 2010. http://dx.doi.org/10.1109/isbi.2010.5490280.

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Webb, A. G. "Challenges for high field clinical MRI." In 2010 IEEE International Symposium on Biomedical Imaging: From Nano to Macro. IEEE, 2010. http://dx.doi.org/10.1109/isbi.2010.5490281.

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Luijten, P. R. "Protocol development for high field clinical MRI." In 2010 IEEE International Symposium on Biomedical Imaging: From Nano to Macro. IEEE, 2010. http://dx.doi.org/10.1109/isbi.2010.5490278.

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van Leeuwen, C., Bart R. Steensma, and Alexander J. E. Raaijmakers. "Ultra-high field MRI RF transmit coil arrays." In 2020 50th European Microwave Conference (EuMC). IEEE, 2021. http://dx.doi.org/10.23919/eumc48046.2021.9338167.

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Rispoli, Joseph V., Matthew D. Wilcox, Samantha By, Steven M. Wright, and Mary P. McDougall. "Effects of coplanar shielding for high field MRI." In 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2016. http://dx.doi.org/10.1109/embc.2016.7592157.

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Zhurbenko, Vitaliy, Kristjan Sundgaard Johannesson, Vincent Boer, and Esben Thade Petersen. "Large field-of-view transmission line resonator for high field MRI." In 2016 46th European Microwave Conference (EuMC). IEEE, 2016. http://dx.doi.org/10.1109/eumc.2016.7824433.

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Kim, Jinyoung, Yuval Duchin, Guillermo Sapiro, Jerrold Vitek, and Noam Harel. "Clinical subthalamic nucleus prediction from high-field brain MRI." In 2015 IEEE 12th International Symposium on Biomedical Imaging (ISBI 2015). IEEE, 2015. http://dx.doi.org/10.1109/isbi.2015.7164104.

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Vergara Gomez, T. S., M. Dubois, K. Rustomji, E. Georget, T. Antonakakis, S. Rapacchi, F. Kober, S. Enoch, and R. Abdeddaim. "Hilbert Fractal Inspired Dipoles for B1 + Field Control in Ultra-High Field MRI." In 2020 Fourteenth International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials). IEEE, 2020. http://dx.doi.org/10.1109/metamaterials49557.2020.9285012.

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Seifi, Bahram, Elena Semouchkina, Warren Perger, Gang Chea Lee, Thomas Neuberger, and Michael Lanagan. "Modified design of the coil probe for high field MRI." In 2015 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting. IEEE, 2015. http://dx.doi.org/10.1109/aps.2015.7305066.

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Duby, T. "Design optimisation of MRI systems and other high field magnets." In IEE Seminar Practical Electromagnetic Design Synthesis. IEE, 1999. http://dx.doi.org/10.1049/ic:19990051.

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Reports on the topic "High Field MRI"

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Kennth Marken. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets. Office of Scientific and Technical Information (OSTI), August 2006. http://dx.doi.org/10.2172/897815.

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Perkins, Dustin. Invasive exotic plant monitoring at Fossil Butte National Monument: 2021 field season. Edited by Alice Wondrak Biel. National Park Service, September 2022. http://dx.doi.org/10.36967/2288496.

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Invasive exotic plant (IEP) species are one of the biggest threats to natural ecosystem integrity and biodiversity, and controlling them is a high priority for the National Park Service. The Northern Colorado Plateau Network (NCPN) selected the early detection of IEPs as one of 11 monitoring protocols to be implemented as part of its long-term monitoring program. This report represents work completed during the 2021 field season at Fossil Butte National Monument (NM). From June 26 to 29, 2021, we recorded a total of 12 different priority IEP species during monitoring. A total of 763 priority IEP patches were recorded along 61.9 kilometers (38.5 mi) of 22 monitoring routes. Summer cypress (Bassia scoparia) was detected for the first time on monitoring routes along the Main Park Road. The highest densities of IEP patches were detected in several drainages and one trail: Sage Grouse Lek Drainage (32.7 patches/km), East Red Hill Drainage (19.4/km), Moose Bones Canyon (19.4/km), Main Park Road (19.0/km), West Fork Chicken Creek (17.6/km), Chicken Creek (15.0/km), Smallpox Creek (13.5/km) and the Historic Quarry Trail (11.1/km). The Fossil Butte Northwest, Wasatch Saddle, and North Dam Fork of Chicken Creek drainages were the only routes free of priority IEPs in 2021. Cheatgrass (Bromus tectorum), creeping foxtail (Alopecurus arundi-naceus), and Japanese brome (Bromus japonicus) were the most widespread species. Creeping foxtail continues to increase parkwide and along the Main Park Road and southern drainages. The two brome species have declined somewhat since 2018, but these species can fluctuate widely based on precipitation. Flixweed (Descurainia sophia), whitetop (Cardaria sp.), and quackgrass (Elymus repens) all appear to have declined since 2018 and their previous highs in earlier years. Control efforts by park staff are likely helping to prevent some IEP increases in the park. Network staff plan to return to Fossil Butte NM for an eighth round of monitoring in 2023.
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3

Levisohn, Sharon, Mark Jackwood, and Stanley Kleven. New Approaches for Detection of Mycoplasma iowae Infection in Turkeys. United States Department of Agriculture, February 1995. http://dx.doi.org/10.32747/1995.7612834.bard.

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Mycoplasma iowae (Mi) is a pathogenic avian mycoplasma which causes mortality in turkey embryos and as such has clinical and economic significance for the turkey breeder industry. Control of Mi infection is severely hampered by lack of adequate diagnostic tests, together with resistance to most antibiotics and resilience to environment. A markedly high degree of intra-species antigenic variation also contributes to difficulties in detection and control of infection. In this project we have designed an innovative gene-based diagnostic test based on specific amplification of the 16S rRNA gene of Mi. This reaction, designed Multi-species PCR-RFLP test, also amplifies the DNA of the pathogenic avian mycoplasmas M. gallisepticum (Mg) and M. synoviae (Ms). This test detects DNA equivalent to about 300 cfu Mi or either of the other two target mycoplasmas, individually or in mixed infection. It is a quick test, applicable to a wide variety of clinical samples, such as allantoic fluid or tracheal or cloacal swab suspensions. Differential diagnosis is carried out by gel electro-phoresis of the PCR amplicon digested with selected restriction enzymes (Restriction Fragment Length Polymorphism). This can also be readily accomplished by using a simple Dot-Blot hybridization assay with digoxigenin-labeled oligonucleotide probes reacting specifically with unique Mi, Mg or Ms sequences in the PCR amplicon. The PCR/OLIGO test increased sensitivity by at least 10-fold with a capacity for rapid testing of large numbers of samples. Experimental infection trials were carried out to evaluate the diagnostic tools and to study pathogenesis of Mi infection. Field studies and experimental infection of embryonated eggs indicated both synergistic and competitive interaction of mycoplasma pathogens in mixed infection. The value of the PCR diagnostic tests for following the time course of egg transmission was shown. A workable serological test (Dot Immunobinding Assay) was also developed but there was no clear-cut evidence that infected turkeys develop an immune response. Typing of a wide spectrum of Mi field isolates by a variety of gene-based molecular techniques indicated a higher degree of genetic homogeneity than predicted on the basis of the phenotypic variability. All known strains of Mi were detected by the method developed. Together with an M. meleagridis-PCR test based on the same gene, the Multi-species PCR test is a highly valuable tool for diagnosis of pathogenic mycoplasmas in single or mixed infection. The further application of this rapid and specific test as a part of Mi and overall mycoplasma control programs will be dependent on developments in the turkey industry.
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4

Perkins, Dustin. Invasive exotic plant monitoring at Colorado National Monument: 2021 field season. Edited by Alice Wondrak Biel. National Park Service, September 2022. http://dx.doi.org/10.36967/2294260.

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Invasive exotic plant (IEP) species are a significant threat to natural ecosystem integrity and biodiversity, and controlling them is a high priority for the National Park Service. The Northern Colorado Plateau Network (NCPN) selected the early detection of IEPs as one of 11 monitoring protocols to be implemented as part of its long-term monitoring program. This report represents work completed at Colorado National Monument during 2021. During monitoring conducted June 9–15, a total of 15 priority IEP species in 395 patches were detected on 53.6 kilometers (33.3 mi) of monitoring routes. An additional four species were detected in transects. Yellow salsify (Tragopogon dubius), ripgut brome (Anisantha diandra), jointed goatgrass (Cylindropyrum cylindricum), and tamarisk (Tamarix sp.) were the most commonly detected priority IEPs along monitoring routes, representing 74% of all priority patches. Except for ripgut brome and broad-leaf pepperwort (Cardaria latifolia), most patches of priority IEPs were than 40 m2. Ninety-five percent of tree patches were classified as seedlings or saplings, which require less effort to control than mature trees. Cheatgrass (Anisantha tectorum) was the most common IEP in transects, found in >63% of transects along every route surveyed. When segments of monitoring routes consistently surveyed from 2005 to 2021 were analyzed, Red Canyon, Wedding Canyon, and Fruita Canyon all had the highest number of IEPs per 100 meters during the entire monitoring period. Increases were driven by increases in jointed goatgrass on all three routes and yellow salsify (Tragopogon dubius) in Wedding Canyon and tamarisk in Red Canyon. Jointed goatgrass appears to be rapidly expanding, increasing from 8 patches in 2019 to 42 patches in 2021 (though the routes surveyed were not all the same). In addition, three species not seen in recent years—Canada thistle (Breea arvensis), bull thistle (Cirsium vulgare), and broad-leaf pepperwort—were detected, but in fewer than 10 patches each. These species should be prioritized for control. The No Thoroughfare, Ute Canyon, and Monument Canyon routes all have stayed relatively stable over time, but at least one patch of jointed goatgrass was found on each. Network staff plans to return to re-sample monitoring routes in 2023.
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5

Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman, and Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.
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6

Cohen, Roni, Kevin Crosby, Menahem Edelstein, John Jifon, Beny Aloni, Nurit Katzir, Haim Nerson, and Daniel Leskovar. Grafting as a strategy for disease and stress management in muskmelon production. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7613874.bard.

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The overall objective of this research was to elucidate the horticultural, pathological, physiological and molecular factors impacting melon varieties (scion) grafted onto M. cannonballus resistant melon and squash rootstocks. Specific objectives were- to compare the performance of resistant melon germplasm (grafted and non-grafted) when exposed to M. cannoballus in the Lower Rio Grande valley and the Wintergarden, Texas, and in the Arava valley, Israel; to address inter-species relationships between a Monosporascus resistant melon rootstock and susceptible melon scions in terms of fruit-set, fruit quality and yield; to study the factors which determine the compatibility between the rootstock and the scion in melon; to compare the responses of graft unions of differing compatibilities under disease stress, high temperatures, deficit irrigation, and salinity stress; and to investigate the effect of rootstock on stress related gene expression in the scion. Some revisions were- to include watermelon in the Texas investigations since it is much more economically important to the state, and also to evaluate additional vine decline pathogens Didymella bryoniae and Macrophomina phaseolina. Current strategies for managing vine decline rely heavily on soil fumigation with methyl bromide, but restrictions on its use have increased the need for alternative management strategies. Grafting of commercial melon varieties onto resistant rootstocks with vigorous root systems is an alternative to methyl bromide for Monosporascus root rot/vine decline (MRR/VD) management in melon production. Extensive selection and breeding has already produced potential melon rootstock lines with vigorous root systems and disease resistance. Melons can also be grafted onto Cucurbita spp., providing nonspecific but efficient protection from a wide range of soil-borne diseases and against some abiotic stresses, but compatibility between the scion and the rootstock can be problematic. During the first year experiments to evaluate resistance to the vine decline pathogens Monosporascus cannonballus, Didymella bryoniae, and Macrophomina phaseolina in melon and squash rootstocks proved the efficacy of these grafted plants in improving yield and quality. Sugars and fruit size were better in grafted versus non-grafted plants in both Texas and Israel. Two melons (1207 and 124104) and one pumpkin, Tetsukabuto, were identified as the best candidate rootstocks in Texas field trials, while in Israel, the pumpkin rootstock RS59 performed best. Additionally, three hybrid melon rootstocks demonstrated excellent resistance to both M. cannonballus and D. bryoniae in inoculated tests, suggesting that further screening for fruit quality and yield should be conducted. Experiments with ABA in Uvalde demonstrated a significant increase in drought stress tolerance and concurrent reduction in transplant shock due to reduced transpiration for ‘Caravelle’ plants. In Israel, auxin was implicated in reducing root development and contributing to increased hydrogen peroxide, which may explain incompatibility reactions with some squash rootstocks. However, trellised plants responded favorably to auxin (NAA) application at the time of fruit development. Gene expression analyses in Israel identified several cDNAs which may code for phloem related proteins, cyclins or other factors which impact the graft compatibility. Manipulation of these genes by transformation or traditional breeding may lead to improved rootstock cultivars. Commercial applications of the new melon rootstocks as well as the ABA and TIBA growth regulators have potential to improve the success of grafted melons in both Israel and Texas. The disease resistance, fruit quality and yield data generated by the field trials will help producers in both locations to decide what rootstock/scion combinations will be best.
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