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“Ironies of the American State” (with Robert C Lieberman), World Politics 61 (July 2009) 547-588.

“American State Building: The Theoretical Challenge” (with Robert C Lieberman) in The Unsustainable American State eds Lawrence Jacobs and Desmond King New York: Oxford University Press, 2009.

“American Political Development as a Process of Democratization,” with Robert C Lieberman, in Democratization in America: A Comparative Historical Analysis, Eds. Desmond King et al. Baltimore: Johns Hopkins University Press, 2009.

Early randomized Phase II cancer chemoprevention trials which assess short-term biological activity are critical to the decision process to advance to late Phase II/Phase III trials. We have adapted published Bayesian interim analysis methods (Spiegelhalter et al., J. R. Statist. Soc A, 1994; 157: 357-416) which give greater flexibility and simplicity of inference to the monitoring of randomized controlled Phase II trials using intermediate endpoints. The Bayesian stopping rule is designed to stop the trial more quickly when the evidence suggests ineffectiveness rather than when it suggests biological activity, thus allowing resources to be concentrated on those agents that show the most promise in this early stage of testing. We investigate frequentist performance characteristics of the proposed method through simulation of randomized placebo controlled trials with a growth factor intermediate end-point using mean and variance values derived from the literature. Simulation results show expected error rates and trial size similar to other commonly used group sequential methods for this setting. These results suggest that the Bayesian approach to interim analysis is well suited for monitoring small randomized controlled Phase II chemoprevention trials for early detection of either inactive or promising agents.

The objective of this study is to compare observed mean meridional winds with those deduced from theory. The diabatic circulation is computed from High Resolution Dopper Imager (HRDI) mesospheric and lower thermospheric temperatures during January and July conditions. The meridional wind component is compared with HRDI Eulerian mean meridional winds near 95 km and with seasonal averages of meridional winds at a number of radar medium-frequency (MF) and meteor wind (MW) sites. The diabatic wind is directed from the summer toward the winter hemisphere. Peak values exceed 20 m s-1 and are observed at 105 km near 20° in the summer hemisphere. A secondary maximum of about 10 m s-1 is observed in the wintertime lower mesosphere during the July case. The diabatic wind is qualitatively consistent with HRDI 95-km mean meridional winds at latitudes equatorward of 50°. Time-averaged summertime radar winds are consistent with HRDI and diabatic winds between 50° S and 20° N. At winter midlatitudes, MF radar winds are directed oppositely to the diabatic wind, while one available MW measurement is directed with the diabatic wind. The zonal acceleration implied by the diabatic wind is about 150-200 m s-1 d-1 in the midlatitude summer lower thermosphere. Copyright 2000 by the American Geophysical Union.

The objective of this study is to compare observed mean meridional winds with those deduced from theory. The diabatic circulation is computed from High Resolution Dopper Imager (HRDI) mesospheric and lower thermospheric temperatures during January and July conditions. The meridional wind component is compared with HRDI Eulerian mean meridional winds near 95 km and with seasonal averages of meridional winds at a number of radar medium-frequency (MF) and meteor wind (MW) sites. The diabatic wind is directed from the summer toward the winter hemisphere. Peak values exceed 20 m s-1 and are observed at 105 km near 20° in the summer hemisphere. A secondary maximum of about 10 m s-1 is observed in the wintertime lower mesosphere during the July case. The diabatic wind is qualitatively consistent with HRDI 95-km mean meridional winds at latitudes equatorward of 50°. Time-averaged summertime radar winds are consistent with HRDI and diabatic winds between 50° S and 20° N. At winter midlatitudes, MF radar winds are directed oppositely to the diabatic wind, while one available MW measurement is directed with the diabatic wind. The zonal acceleration implied by the diabatic wind is about 150-200 m s-1 d-1 in the midlatitude summer lower thermosphere. Copyright 2000 by the American Geophysical Union.

High Resolution Doppler Imager (HRDI) measurements of daytime and nighttime winds at 95 km are used to deduce seasonally averaged Eulerian mean meridional winds during six solstice periods. These estimates are compared with seasonally averaged radar meridional winds and with results from dynamical and empirical wind models. HRDI mean meridional winds are directed from the summer pole toward the winter pole over much of the globe. Peak equatorward winds of about 15 m s-1 are usually observed in the summer hemisphere near 30°. A local minimum in the equatorward winds is often observed poleward of this latitude, with winds approaching zero or reversing direction. A similar structure is seen in contemporaneous radar winds. This behavior differs from residual meridional wind patterns predicted by models. The discrepancies may be related to gravity wave paramaterizations or a consequence of planetary wave influences.

The authors show here that progesterone suppresses apoptosis, and its antagonist RU 486 induces it in rabbit uterine epithelium, as assessed by morphologic and biochemical studies. The authors' studies demonstrate that internucleosomal DNA fragments are identifiable as early as 24 hours after ovariectomy of pseudopregnant rabbits, and become undetectable 6 days after ovariectomy. Maximal levels of DNA fragmentation (about 74% of total isolated DNA) were observed 36 hours after ovariectomy. The number of apoptotic cells appeared to increase parallel to the increased DNA breakdown, and accounted for approximately 26% of the uterine epithelial cells at 48 hours after ovariectomy. Levels of progesterone in serum dropped precipitously 6 hours after ovariectomy and remained very low for several days. Administration of progesterone, more than any other steroid hormone, to pseudopregnant ovariectomized rabbits, prevented the increase in apoptotic cell death. By contrast, administration of the anti-progestin RU 486 to pseudopregnant rabbits triggered apoptosis, which attained levels similar to those observed in ovariectomized animals. The authors' findings establish that uterine epithelium apoptosis occurs in a time-dependent fashion and provides strong evidence that the actions of progesterone in that tissue are not only to stimulate cell proliferation and differentiation, but also to suppress apoptosis.

Guillain-Barré syndrome is an acquired disease of the peripheral nervous system. The etiology appears to be autoimmune in nature. The major clinical features are progressive weakness and loss of reflexes, with respiratory failure being a serious complication. The prognosis for Guillain-Barré syndrome in children is good with proper intensive care and early detection of the disease.

Digital subtraction angiography (DSA) has replaced standard angiography in the preoperative evaluation of patients with pituitary adenomas and is superior to standard angiography in the evaluation of the dural sinuses. Postoperative assessment of intracranial aneurysms, arteriovenous malformations and grafts has also been accomplished by DSA. In addition, the DSA technique may be utilized in conjunction with intraarterial injections of contrast material to reduce film cost and increase patient comfort.