Dynamics of a classical Hall system driven by a time-dependent Aharonov--Bohm flux

We study the dynamics of a classical particle moving in a punctured plane under the influence of a strong homogeneous magnetic field, an electrical background, and driven by a time-dependent singular flux tube through the hole. We exhibit a striking classical (de)localization effect: in the far past the trajectories are spirals around a bound center; the particle moves inward towards the flux tube loosing kinetic energy. After hitting the puncture it becomes ``conducting'': the motion is a cycloid around a center whose drift is outgoing, orthogonal to the electric field, diffusive, and without energy loss

Evaluating Residency Programs by Whether They Produce Good Doctors

Not all physician training programs are alike. Many physicians and non-physicians believe that graduates of some training programs deliver better care, although this intuition has not been tested. Residency programs provide physicians with in-depth specialty training (usually lasting 3-6 years). Can the quality of that training be judged by the downstream outcomes of patients treated by their graduates? Should patients pick their doctors in part by where they trained? This Issue Brief looks at one specialty—obstetrics and gynecology (OB)—and explores whether OB training programs can be distinguished by the quality of care their graduates provide

Comparing VA and Non-VA Health Care: the Case of Post-Stroke Rehabilitation

The Department of Veterans Affairs (VA) runs the largest integrated health system in the country, and provides care to nearly 4 million patients each year. It has been dogged by persistent doubts about its efficiency and quality of care, despite numerous quality improvement programs and an extensive reorganization in 1995. In fact, recent studies have found that health care in the VA compares favorably with non-VA systems, in areas such as preventive care and treatment for acute myocardial infarction. This Issue Brief summarizes a comparison in another area—inpatient rehabilitation for stroke— and highlights the difficulty and complexity of assessing quality across systems of care

Behavioral Economics and Health Annual Symposium

The application of behavioral economics to health and health care has captured the imagination of policymakers across the political spectrum. The idea is that many people are irrational in predictable ways, and that this both contributes to unhealthy behaviors like smoking and holds one of the keys to changing those behaviors. Because health care costs continue to increase, and a substantial portion of costs are incurred because of unhealthy behaviors, employers and insurers have great interest in using financial incentives to change behaviors. However, it is in the details that complexity and controversies emerge. Who should the targets be, and what outcomes should be rewarded? How should incentives be structured, to maximize their effectiveness and minimize unintended consequences? In what situations should we be intervening to affect decisions by people who may prefer to be obese or to smoke, and in what situations should we accept their preferences? To begin to answer these questions, the Penn-CMU Roybal P30 Center on Behavioral Economics and Health held its first annual Behavioral Economics and Health Symposium on March 24-25, 2011 with support from the Robert Wood Johnson Foundation. The symposium drew more than 50 researchers, scholars, and health professionals from a variety of disciplines, including medicine, public health, economics, law, management, marketing, and psychology. They heard perspectives on behavioral economics from public and private funders, the CEO of the University of Pennsylvania Health System, and the CEO of stickK.com, a start-up company that uses online, voluntary commitment contracts to help people achieve their goals. Participants formed eight working groups to review the current state-of-the-art in a variety of clinical contexts and to consider how behavioral economics could inform a research agenda to improve health. This Issue Brief summarizes the findings of these working groups and the symposium

Professional and Public Attitudes Toward Incentives for Organ Donation

The U.S. faces a widening gap between the need for, and the supply of, transplantable organs. The waiting list for transplants increased 150% in the past decade; last year, about 6,000 people died awaiting a transplant. This need has rekindled debate about the morality and feasibility of using incentives to encourage posthumous organ donation. This Issue Brief explores attitudes of the public and health professionals in the transplant community about using financial and nonfinancial incentives to increase the supply of cadaver organs for transplant

Identification of a gene encoding GMP synthetase from a Neurospora crassa cDNA library by bacterial complementation

We report the isolation and identification of a gene encoding GMP synthetase from a Neurospora crassa cDNA library. Phage infection of the purine-requiring Escherichia coli strain SØ3834 using the NO3- induced cDNA phage library from the Fungal Genetics Stock Center resulted in colonies able to grow on minimal media with no added purine source. A plasmid, termed pGMPS1, was isolated from one of these colonies and shown to reproducibly support growth of strain SØ3834 in the absence of purines in the media. Identification of this gene as one encoding GMP synthetase is confirmed by DNA sequencing and comparison to the known guaA gene from yeast

On the Way to Health

Information technology (IT) has fundamentally changed the way we work, bank, and communicate. Its impact on health care and health research, however, has been limited by the lack of a comprehensive infrastructure to connect patients, providers, and researchers. As we learn more about how to address the unhealthy behaviors that underlie many chronic conditions, researchers are seeking IT solutions to connect to patients in scalable ways. This Issue Brief describes the development and use of a new web-based IT platform, Way to Health, to deliver and evaluate behavioral interventions to improve health