OncoLog Volume 50, Number 04, April 2005

Harnessing the Immune System: The Promise and Potential of Cancer Vaccines Considering Prophylactic Surgery Chemotherapy and Hair Loss DiaLog: Redefining Success in Cancer Care, by Michael Fisch, MD, MPH, Medical Director, Community Clinical Oncology Programhttps://openworks.mdanderson.org/oncolog/1148/thumbnail.jp

OncoLog Volume 50, Number 04, April 2005

Harnessing the Immune System: The Promise and Potential of Cancer Vaccines Considering Prophylactic Surgery House Call: Chemotherapy and Hair Loss DiaLog: Redefining Success in Cancer Care, by Michael Fisch, MD, MPH, Medical Director, Community Clinical Oncology Programhttps://openworks.mdanderson.org/oncolog/1141/thumbnail.jp

Electron-wall interaction in Hall thrusters

Electron-wall interaction effects in Hall thrusters are studied through measurements of the plasma response to variations of the thruster channel width and the discharge voltage. The discharge voltage threshold is shown to separate two thruster regimes. Below this threshold, the electron energy gain is constant in the acceleration region and therefore, secondary electron emission (SEE) from the channel walls is insufficient to enhance electron energy losses at the channel walls. Above this voltage threshold, the maximum electron temperature saturates. This result seemingly agrees with predictions of the temperature saturation, which recent Hall thruster models explain as a transition to space-charge saturated regime of the near-wall sheath. However, in the experiment, the maximum saturation temperature exceeds by almost three times the critical value estimated under the assumption of a Maxwellian electron energy distribution function. The channel narrowing, which should also enhance electron-wall collisions, causes unexpectedly larger changes of the plasma potential distribution than does the increase of the electron temperature with the discharge voltage. An enhanced anomalous crossed-field mobility (near wall or Bohm-type) is suggested by a hydrodynamic model as an explanation to the reduced electric field measured inside a narrow channel. We found, however, no experimental evidence of a coupling between the maximum electron temperature and the location of the accelerating voltage drop, which might have been expected due to the SEE-induced near-wall conductivity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87763/2/057104_1.pd

OncoLog Volume 52, Number 10, October 2007

Cancer Chemoprevention: A Prescription for Health? Clinic Targets Oral Cancer at Early Stages Customized Cancer Care for Kids Hotline Consultation Available for Suspected Cancer Cases House Call: Cancer Stages: Understanding the Basics DiaLog: Rethinking the Standard of Care, by Michael Fisch, MD, MPHhttps://openworks.mdanderson.org/oncolog/1163/thumbnail.jp

Implicit Communication and Enforcement of Corporate Disclosure Regulation

This study examines the challenge of implicit communication -- qualitative statements, tone, and non-verbal cues -- to the effectiveness of enforcing corporate disclosure regulation. We use a Regulation Fair Disclosure (Reg FD) setting, given that the SEC adopted the regulation recognizing that managers can convey non-public information privately not just through explicit quantitative disclosures but also through implicit communication. In a high-profile enforcement action, however, the court focused on a literal examination of the manager’s language rather than his positive spin to conclude that the SEC had been “too demanding” in examining the manager’s statements and that its enforcement policy was “overly aggressive.” We provide empirical evidence suggesting that selective disclosure from managers to financial analysts increased significantly after the court’s ruling. We also report survey responses from 60 securities lawyers with Reg FD expertise which support the proposition that this increase in disclosure is more likely due to an increase in implicit communication than in explicit communication or any other reason. Our results highlight the challenges associated with enforcing corporate disclosure regulation in the context of implicit communication

Characterization of plasma in a Hall thruster operated at high discharge voltage

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77205/1/AIAA-2005-4404-466.pd