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21.
Cheryl A. Hoover Robert T. Sataloff Karen M. Lyons Mary Hawkshaw 《Journal of voice》2001,15(3):451-455
Vocal fold mucosal tears have been discussed in the literature rarely, although they are not uncommon clinically. Disruptions in the epithelium usually follow trauma that may result from voice abuse and/or misuse, coughing, and other causes. A high index of suspicion is necessary to avoid missing vocal fold mucosal tears, and strobovideolaryngoscopy is indispensable in making the diagnosis. A brief period of complete voice rest is the standard of care and appears to be helpful in avoiding adverse sequelae and advancing the healing process, but there are no scientific studies to confirm its efficacy. Mucosal tears may heal completely or may be followed by the development of vocal fold masses, scar, and permanent dysphonia. 相似文献
22.
This paper summarizes some of the experimental procedures used for making homopolymers and copolymers of dimethyldiallylammonium chloride, along with a discussion of some of the experimental variables such as effects of catalyst ratio, monomer concentration, and impurities. Also discussed are some of the procedures used for evaluation of the polymers and copolymers in flocculation and sludge dewatering. 相似文献
23.
Aerobic oxidation reactions have been the focus of considerable attention, but their use in mainstream organic chemistry has been constrained by limitations in their synthetic scope and by practical factors, such as the use of pure O(2) as the oxidant or complex catalyst synthesis. Here, we report a new (bpy)Cu(I)/TEMPO catalyst system that enables efficient and selective aerobic oxidation of a broad range of primary alcohols, including allylic, benzylic, and aliphatic derivatives, to the corresponding aldehydes using readily available reagents, at room temperature with ambient air as the oxidant. The catalyst system is compatible with a wide range of functional groups and the high selectivity for 1° alcohols enables selective oxidation of diols that lack protecting groups. 相似文献
24.
Gorham PW Barwick SW Beatty JJ Besson DZ Binns WR Chen C Chen P Clem JM Connolly A Dowkontt PF DuVernois MA Field RC Goldstein D Goodhue A Hast C Hebert CL Hoover S Israel MH Kowalski J Learned JG Liewer KM Link JT Lusczek E Matsuno S Mercurio B Miki C Miocinović P Nam J Naudet CJ Ng J Nichol R Palladino K Reil K Romero-Wolf A Rosen M Ruckman L Saltzberg D Seckel D Varner GS Walz D Wu F;ANITA Collaboration 《Physical review letters》2007,99(17):171101
We report on observations of coherent, impulsive radio Cherenkov radiation from electromagnetic showers in solid ice. This is the first observation of the Askaryan effect in ice. As part of the complete validation process for the ANITA experiment, we performed an experiment at the Stanford Linear Accelerator Center in June 2006 using a 7.5 metric ton ice target. We measure for the first time the large-scale angular dependence of the radiation pattern, a major factor in determining the solid-angle acceptance of ultrahigh-energy neutrino detectors. 相似文献
25.
Monoacylglycerol lipase exerts dual control over endocannabinoid and fatty acid pathways to support prostate cancer 总被引:1,自引:0,他引:1
Nomura DK Lombardi DP Chang JW Niessen S Ward AM Long JZ Hoover HH Cravatt BF 《Chemistry & biology》2011,18(7):846-856
Cancer cells couple heightened lipogenesis with lipolysis to produce fatty acid networks that support malignancy. Monoacylglycerol lipase (MAGL) plays a principal role in this process by converting monoglycerides, including the endocannabinoid 2-arachidonoylglycerol (2-AG), to free fatty acids. Here, we show that MAGL is elevated in androgen-independent versus androgen-dependent human prostate cancer cell lines, and that pharmacological or RNA-interference disruption of this enzyme impairs prostate cancer aggressiveness. These effects were partially reversed by treatment with fatty acids or a cannabinoid receptor-1 (CB1) antagonist, and fully reversed by cotreatment with both agents. We further show that MAGL is part of a gene signature correlated with epithelial-to-mesenchymal transition and the stem-like properties of cancer cells, supporting a role for this enzyme in protumorigenic metabolism that, for prostate cancer, involves the dual control of endocannabinoid and fatty acid pathways. 相似文献
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A. S. Hoover M. K. Bacrania N. J. Hoteling P. J. Karpius M. W. Rabin C. R. Rudy D. T. Vo J. A. Beall D. A. Bennett W. B. Doriese G. C. Hilton R. D. Horansky K. D. Irwin J. N. Ullom L. R. Vale 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(1):227-232
Microcalorimeter detectors provide superior energy resolution for the detection of X-rays and gamma-rays. The technology utilizes a cryogenic transition-edge sensor (TES) coupled to a tin bulk absorber. We are working on fabrication methods for the production of arrays with many sensors. In this paper, we present data collected with an array of microcalorimeters using as many as 26 sensor elements simultaneously. Advances in sensor design have extended the useful dynamic range to photon energies up to ~200 keV, while providing resolution performance in the 80–90 eV FWHM range, significantly better than planar high-purity germanium. These sensor arrays have applications in the measurement of nuclear materials. We present data collected from 153Gd, a highly-enriched uranium sample, and a plutonium isotopic standard source. We also demonstrate clean separation of the 235U 185.715 keV peak from the ubiquitous 226Ra 186.211 keV background peak interference. 相似文献
29.
Hoover S Nam J Gorham PW Grashorn E Allison P Barwick SW Beatty JJ Belov K Besson DZ Binns WR Chen C Chen P Clem JM Connolly A Dowkontt PF DuVernois MA Field RC Goldstein D Vieregg AG Hast C Israel MH Javaid A Kowalski J Learned JG Liewer KM Link JT Lusczek E Matsuno S Mercurio BC Miki C Miočinović P Naudet CJ Ng J Nichol RJ Palladino K Reil K Romero-Wolf A Rosen M Ruckman L Saltzberg D Seckel D Varner GS Walz D Wu F 《Physical review letters》2010,105(15):151101
We report the observation of 16 cosmic ray events with a mean energy of 1.5 × 101? eV via radio pulses originating from the interaction of the cosmic ray air shower with the Antarctic geomagnetic field, a process known as geosynchrotron emission. We present measurements in the 300-900 MHz range, which are the first self-triggered, first ultrawide band, first far-field, and the highest energy sample of cosmic ray events collected with the radio technique. Their properties are inconsistent with current ground-based geosynchrotron models. The emission is 100% polarized in the plane perpendicular to the projected geomagnetic field. Fourteen events are seen to have a phase inversion due to reflection of the radio beam off the ice surface, and two additional events are seen directly from above the horizon. Based on a likelihood analysis, we estimate angular pointing precision of order 2° for the event arrival directions. 相似文献
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