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JG Williams

Publications and source records attributed to JG Williams.

4 recordsLinked to original sources
PubMed1998

Improved gravity field of the moon from lunar prospector

An improved gravity model from Doppler tracking of the Lunar Prospector (LP) spacecraft reveals three new large mass concentrations (mascons) on the nearside of the moon beneath the impact basins Mare Humboltianum, Mendel-Ryberg, and Schiller-Zucchius, where the latter basin has no visible mare fill. Although there is no direct measurement of the lunar farside gravity, LP partially resolves four mascons in the large farside basins of Hertzsprung, Coulomb-Sarton, Freundlich-Sharonov, and Mare Moscoviense. The center of each of these basins contains a gravity maximum relative to the surrounding basin. The improved normalized polar moment of inertia (0.3932 +/- 0.0002) is consistent with an iron core with a radius of 220 to 450 kilometers.

Journal Article↗
PubMed1995

Acute Presentations of Bile Duct Calculi.

The majority of bile duct stones in Western patients originate in the gallbladder. Many patients with bile duct stones are asymptomatic. However, the acute complications of bile duct calculi-jaundice, cholangitis, and pancreatitis-may present in insolation or in combination with each other. Successful treatment of cholangitis and severe biliary pancreatitis requires urgent biliary decompression, which is best achieved by endoscopic sphincterotomy. Similarly, endoscopic sphincterotomy is the most appropriate method of relieving obstructive jaundice caused by biliary stones and, in some patients, may be the sole treatment required. Surgical intervention rarely is necessary in the acute stage, although definitive surgery may be required later, when the patient's clinical condition has improved.

Journal Article↗