RESUMO
The generation, manipulation and quantification of non-classical light, such as quantum-entangled photon pairs, differs significantly from methods with classical light. Thus, quantum measures could be harnessed to give new information about the interaction of light with matter. In this study we investigate if quantum entanglement can be used to diagnose disease. In particular, we test whether brain tissue from subjects suffering from Alzheimer's disease can be distinguished from healthy tissue. We find that this is indeed the case. Polarization-entangled photons traveling through brain tissue lose their entanglement via a decohering scattering interaction that gradually renders the light in a maximally mixed state. We found that in thin tissue samples (between 120 and 600 micrometers) photons decohere to a distinguishable lesser degree in samples with Alzheimer's disease than in healthy-control ones. Thus, it seems feasible that quantum measures of entangled photons could be used as a means to identify brain samples with the neurodegenerative disease.
RESUMO
OBJECTIVE: To compare physicians' and their patients' attitudes toward pharmaceutical gifts. DESIGN: Survey of physicians and their patients. SETTING: Two tertiary-care medical centers, one military and one civilian. PARTICIPANTS: Two hundred sixty-eight of 392 consecutively surveyed physicians, 100 of 103 randomly selected patients at the military center, and 96 patients in a convenience sample at the civilian center completed the survey. MEASUREMENTS: Participants rated 10 pharmaceutical gifts on whether they were appropriate for physicians to accept and whether they were likely to influence prescribing. Patients found gifts less appropriate and more influential than did their physicians. About half of the patients were aware of such gifts; of those unaware, 24% responded that this knowledge altered their perception of the medical profession. Asked whether they thought their own physician accepted gifts, 27% said yes, 20% no, and 53% were unsure. For patients, feeling that gifts were inappropriate was best predicted by a belief that gifts might influence prescribing, while for physicians, the best predictor was knowledge of guidelines. CONCLUSIONS: Patients feel pharmaceutical gifts are more influential and less appropriate than do their physicians. Physicians may want to consider this in deciding whether to accept particular gifts. Broader dissemination of guidelines may be one means of changing physician behavior. At the same time, future guidelines should further consider the potentially different viewpoints of patients and physicians.