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Many people attempt to give meaning to their lives by pursuing projects that they believe will bear fruit after they have died. Knowing that their death will preclude them from protecting or promoting such projects people who draw meaning from them will often attempt to secure their continuance by securing promises from others to serve as their caretakers after they die. But those who rely on such are faced with a problem: None of the four major accounts that have been developed to explain directed promissory obligation (the Authority View, the Trust View, the Assurance View, and the Reliance View) support the view that we are obligated to keep our promises to persons who are now dead. But I will provide hope for those who wish to use such promises to protect the meaning with which they have endowed their lives. I will argue that while we cannot wrong a person who is now dead by breaking a promise made to her during her life, we could wrong the living by so doing. We thus (might) have reason to keep the promises that we made to those who are now dead.
The Fontan Outcomes Network was created to improve outcomes for children and adults with single ventricle CHD living with Fontan circulation. The network mission is to optimise longevity and quality of life by improving physical health, neurodevelopmental outcomes, resilience, and emotional health for these individuals and their families. This manuscript describes the systematic design of this new learning health network, including the initial steps in development of a national, lifespan registry, and pilot testing of data collection forms at 10 congenital heart centres.
Mapping the diversity of SNe to progenitor properties is key to our understanding of stellar evolution and explosive stellar death. Investigations of the immediate environments of SNe allow statistical constraints to be made on progenitor properties such as mass and metallicity. Here, we review the progress that has been made in this field. Pixel statistics using tracers of e.g. star formation within galaxies show intriguing differences in the explosion sites of, in particular SNe types II and Ibc (SNe II and SNe Ibc respectively), suggesting statistical differences in population ages. Of particular interest is that SNe Ic are significantly more associated with host galaxy Hα emission than SNe Ib, implying shorter lifetimes for the former. In addition, such studies have shown (unexpectedly) that the interacting SNe IIn do not explode in regions containing the most massive stars, which suggests that at least a significant fraction of their progenitors arise from the lower end of the core-collapse SN mass range. Host H ii region spectroscopy has been obtained for a significant number of core-collapse events, however definitive conclusions on differences between distinct SN types have to-date been elusive. Single stellar evolution models predict that the relative fraction of SNe Ibc to SNe II should increase with increasing metallicity, due to the dependence of mass-loss rates on progenitor metallicity. We present a meta-analysis of all current host H ii region oxygen abundances for CC SNe. It is concluded that the SN II to SN Ibc ratio shows little variation with oxygen abundance, with only a suggestion that the ratio increases in the lowest bin. Radial distributions of different SNe are discussed, where a central excess of SNe Ibc has been observed within disturbed galaxy systems, which is difficult to ascribe to metallicity or selection effects. Environment studies are also being undertaken for SNe Ia, where constraints can be made on the shortest delay times of progenitor systems. It is shown that ‘redder’ SNe Ia are more often found within star-forming regions. Environment studies are evolving to enable studies at higher spatial resolutions than previously possible, while in addition the advent of wide-field integral field unit instruments allows galaxy-wide spectral analyses which will provide fruitful results to this field. Some example contemporary results are shown in that direction.
Markets have long had a whiff of sulphur about them. Plato condemned innkeepers, whose pursuit of profit he believed led them to take advantage of their customers, Aristotle believed that the pursuit of profit was indicative of moral debasement, and Cicero held that retailers are typically dishonest as this was the only path to gain. And even those who are more favorably disposed towards markets in general are frequently inclined to be suspicious of markets in medical goods and services. For example, Margaret Thatcher (to take someone far removed — in many respects! — from Plato, Aristotle, and Cicero) supported the legal prohibition of markets in kidneys despite being arguably the most pro-market Prime Minister the United Kingdom saw in the 20th century.
We present constraints on core-collapse supernova progenitors through observations of their environments within host galaxies. This is achieved through 2 routes. Firstly, we investigate the spatial correlation of supernovae with host galaxy star formation using pixel statistics. We find that the main supernova types form a sequence of increasing association to star formation. The most logical interpretation is that this implies an increasing progenitor mass sequence going from the supernova type Ia arising from the lowest mass, through the type II, type Ib, and the supernova type Ic arising from the highest mass progenitors. We find the surprising result that the supernova type IIn show a lower association to star formation than type IIPs, implying lower mass progenitors. Secondly, we use host HII region spectroscopy to investigate differences in environment metallicity between different core-collapse types. We find that supernovae of types Ibc arise in slightly higher metallicity environments than type II events. However, this difference is not significant, implying that progenitor metallicity does not play a dominant role in deciding supernova type.
This report examines patterns of influenza vaccination among preclinical and clinical medical students. We used an anonymous online survey to examine medical student behavior and knowledge. Students on clinical rotations, women, and students with better knowledge about the vaccine were more likely to receive the vaccine.
Implantable cardiac pacemakers and defibrillators have greatly decreased the morbidity and mortality rates associated with cardiac arrhythmias. Increasing numbers of people are receiving these devices as the procedures for implantation and device technology improve; as a result, increasing numbers of devices are at risk for infection. The cumulative risk of pacemaker- and defibrillator-related infections after implantation has been estimated to be between 1% and 19% over the lifetime of the device. Infection of these implantable devices is associated with excess morbidity, including prolonged hospital stays and mortality rates as high as 30% in one series.
The first single-chamber permanent pacemakers were introduced for clinical use in the late 1950s. Today, it is estimated that more than 1 million people in the United States have permanent pacemakers. The pacemaker itself consists of a generator, placed below the pectoral muscle, that serves as the power source. An electrical stimulus from the generator travels through an insulated electrical conductor to the electrodes, which deliver the impulse to the endocardium or epicardial surface.
Early implantable cardioverter defibrillator devices (ICDs) required surgical placement of epicardial defibrillation patches, which was facilitated by sternotomy, lateral thoracotomy, or subxiphoid approach. Since 1988, transvenous placement of endocardial coils, similar to pacemakers, has become routine practice. In addition, generator packs have become smaller, allowing for pectoral placement as opposed to the traditional abdominal placement of larger, older generators.
Autonomy has recently become one of the central concepts in contemporary moral philosophy and has generated much debate over its nature and value. This 2005 volume brings together essays that address the theoretical foundations of the concept of autonomy, as well as essays that investigate the relationship between autonomy and moral responsibility, freedom, political philosophy, and medical ethics. Written by some of the most prominent philosophers working in these areas, this book represents research on the nature and value of autonomy that will be essential reading for a broad swathe of philosophers as well as many psychologists.