"The fixed person for fixed duties, who in older societies was such a godsend, in the future ill be a public danger." Twenty years ago, a single legal metaphor accurately captured the role that American society accorded to physicians. The physician was "c- tain of the ship." Physicians were in charge of the clinic, the Operating room, and the health care team, responsible - and held accountabl- for all that happened within the scope of their supervision. This grant of responsibility (...) carried with it a corresponding grant of authority; like the ship's captain, the physician was answerable to no one regarding the practice of his art. However compelling the metaphor, few would disagree that the mandate accorded to the medical profession by society is changing. As a result of pressures from a number of diverse directions - including technological advances, the development of new health professionals, changes in health care financing and delivery, the recent emphasis on consumer choice and patients' rights - what our society expects phy- cians to do and to be is different now. The purpose of this volume is to examine and evaluate the conceptual foundations and the moral imp- cations of that difference. Each of the twelve essays of this volume assesses the current and future validity of the "captain of the ship" metaphor from a different perspective. The essays are grouped into four sections. In Section I, Russell Maulitz explores the physician's role historically. (shrink)

This invaluable resource is the first one-volume, in-depth, comprehensive history of modern science ever published.

In the United Kingdom, the debate about how best to meet the shortfall of organs for transplantation has persisted on and off for many years. It is often presumed that the answer is simply to alter the law to a system of presumed consent. Acting perhaps on that presumption in his annual report launched in July, the Chief Medical Officer, Sir Liam Donaldson, advocated a system of organ donation based on presumed consent, the so-called “opt-out” system.1 He is calling for (...) a change in the law in England and Wales whereby consent to organ donation is presumed, making a person’s organs automatically available for transplantation after death, unless they registered objections to this while alive. Subsequently, the British Medical Association lent its support to the introduction of such a system.2 The BMA contends that “the practice of presumed consent legislation has had a significant effect on the number of cadaveric donors per million population.”2It is often taken for granted that there must be a correlation between the enactment of legislation on presumed consent and an increase in organ donation and procurement. However, the correlation is not as straightforward as it might seem. It may be that other practical measures to encourage organ donation could be implemented without changing the Human Tissue Act 2004, an Act which has been in force for barely a year.An analysis by Abadie and Gay demonstrated that “presumed consent legislation has a positive and sizeable effect on organ donation rates”,3 but they themselves admitted that the correlation between rates of donation and presumed consent legislation is “not completely unequivocal”.3 It is true that among the most successful cases in procurement rates are countries with presumed consent legislation . However, since some of the …. (shrink)

Oxidative damage to DNA has been associated with neurodegenerative diseases. Developmental exposure to lead has been shown to elevate the Alzheimer's disease related beta-amyloid peptide , which is known to generate reactive oxygen species in the aging brain. This study measures the lifetime cerebral 8-hydroxy-2'-deoxyguanosine levels and the activity of the DNA repair enzyme 8-oxoguanine DNA glycosylase in rats developmentally exposed to Pb. Oxo8dG was transiently modulated early in life , but was later elevated 20 months after exposure to Pb (...) had ceased, while Ogg1 activity was not altered. Furthermore, an age-dependent loss in the inverse correlation between Ogg1 activity and oxo8dG accumulation was observed. The effect of Pb on oxo8dG levels did not occur if animals were exposed to Pb in old age. These increases in DNA damage occurred in the absence of any Pb-induced changes in copper/zinc-superoxide dismutase , manganese-SOD , and reduced-form glutathion . These data suggest that oxidative damage and neurodegeneration in the aging brain could be impacted by the developmental disturbances. (shrink)

Bachelard, Gaston; criticism and interpretation; knowledge, theory of; science; philosophy.

We apply an online optimization process based on machine learning to the production of Bose-Einstein condensates. BEC is typically created with an exponential evaporation ramp that is optimal for ergodic dynamics with two-body s-wave interactions and no other loss rates, but likely sub-optimal for real experiments. Through repeated machine-controlled scientific experimentation and observations our ’learner’ discovers an optimal evaporation ramp for BEC production. In contrast to previous work, our learner uses a Gaussian process to develop a statistical model of the (...) relationship between the parameters it controls and the quality of the BEC produced. We demonstrate that the Gaussian process machine learner is able to discover a ramp that produces high quality BECs in 10 times fewer iterations than a previously used online optimization technique. Furthermore, we show the internal model developed can be used to determine which parameters are essential in BEC creation and which are unimportant, providing insight into the optimization process of the system. (shrink)

As a preliminary step to beginning to assess the usefulness of clinical vignettes to measure ethical sensitivity in undergraduate medical students, five clinical vignettes with seven to nine ethical issues each were created. The ethical issues in the vignettes were discussed and outlined by an expert panel. One randomly selected vignette was presented to first, second and third year students at the University of Toronto as part of another examination. The students were asked to list the issues presented by the (...) patient problem. Responses from 281 students were obtained. These students identified an average of 2.72 ethical issues per vignette. Each response was classified under the domains of autonomy, beneficence and justice. Comparisons were made between classes and between vignettes. There was considerable variation between classes and the responses to different vignettes seem to indicate that different vignettes measure the various domains in different ways. It does appear that the use of vignettes is one way to measure aspects of ethical sensitivity in medical students but more study is required to clarify exactly what is being measured. (shrink)

The particle internal clock conjectured by de Broglie in 1924 was investigated in a channeling experiment using a beam of ∼80 MeV electrons aligned along the 〈110〉 direction of a 1 μm thick silicon crystal. Some of the electrons undergo a rosette motion, in which they interact with a single atomic row. When the electron energy is finely varied, the rate of electron transmission at 0° shows a 8% dip within 0.5% of the resonance energy, 80.874 MeV, for which the (...) frequency of atomic collisions matches the electron’s internal clock frequency. A model is presented to show the compatibility of our data with the de Broglie hypothesis. (shrink)