@article {267,
	title = {Hyperpolarized xenon NMR and MRI signal amplification by gas extraction},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {106},
	year = {2009},
	note = {P Natl Acad Sci USA503MDTimes Cited:12Cited References Count:33},
	month = {Oct 6},
	pages = {16903-16906},
	abstract = {<p>A method is reported for enhancing the sensitivity of NMR of dissolved xenon by detecting the signal after extraction to the gas phase. We demonstrate hyperpolarized xenon signal amplification by gas extraction (Hyper-SAGE) in both NMR spectra and magnetic resonance images with time-of-flight information. Hyper-SAGE takes advantage of a change in physical phase to increase the density of polarized gas in the detection coil. At equilibrium, the concentration of gas-phase xenon is approximate to 10 times higher than that of the dissolved-phase gas. After extraction the xenon density can be further increased by several orders of magnitude by compression and/or liquefaction. Additionally, being a remote detection technique, the Hyper-SAGE effect is further enhanced in situations where the sample of interest would occupy only a small proportion of the traditional NMR receiver. Coupled with targeted xenon biosensors, Hyper-SAGE offers another path to highly sensitive molecular imaging of specific cell markers by detection of exhaled xenon gas.</p>
},
	keywords = {field},
	isbn = {0027-8424},
	doi = {Doi 10.1073/Pnas.0909147106},
	url = {<Go to ISI>://WOS:000270537500005},
	author = {Zhou, X. and Graziani, D. and Pines, A.}
}
@article {278,
	title = {Volume-selective magnetic resonance imaging using an adjustable, single-sided, portable sensor},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {105},
	year = {2008},
	note = {P Natl Acad Sci USA389LBTimes Cited:11Cited References Count:29},
	month = {Dec 30},
	pages = {20601-20604},
	abstract = {<p>Portable, single-sided NMR sensors can operate under conditions inaccessible to conventional NMR while featuring lower cost, portability, and the ability to analyze arbitrary-sized objects. Such sensors can nondestructively probe the interior of samples by collecting images and measuring relaxation and diffusion constants, and, given careful shimming schemes, even perform chemical analysis. The inherently strong magnetic-field gradients of single-sided sensors developed so far has prevented imaging of materials with high water content, such as biological tissues, over large volumes whereas designs with more homogeneous fields suffer from low field strength and typically cannot probe volumes larger than approximate to 10 cm(3). We present a design with a continuously adjustable sensitive volume, enabling the effective volume to be enlarged several fold. This capability allows for imaging in reasonable times of much bigger objects and opens the door to the possibility of clinical imaging with portable sensors. We demonstrate MRI in axial and sagittal planes, at different depths of the sensitive volume and T(1)-weighted contrast in a tissue sample.</p>
},
	keywords = {xenon},
	isbn = {0027-8424},
	doi = {Doi 10.1073/Pnas.0811222106},
	url = {<Go to ISI>://WOS:000262092800008},
	author = {Paulsen, J. L. and Bouchard, L. S. and Graziani, D. and Blumich, B. and Pines, A.}
}
