For many, Thomas Beauchamp and James Childress have elaborated moral reasoning by using the four principles whereby all substantive problems of medical ethics (and of ethics more generally) can be properly analysed and cogent philosophical solutions for the problems can be found. It seems that their ‘principlism’ gets updated, with better features being added during the course of the six editions of Principles of Biomedical Ethics. Nonetheless, Beauchamp and Childress seem to have been losing their way when it comes to (...) the common-morality justification, which is the epistemological (and perhaps metaphysical) backbone of their method, and this is shown more vividly in their most recent (2009) edition of Principles of Biomedical Ethics. The author points out what he calls the problem of ‘thick in status, thin in content’ in principlism. The problem exists because principlism cannot adequately explain how the prescriptive sense of common morality it supports is consistent with the existence of what Beauchamp and Childress call the ‘legitimate moral diversity in the world’. Because of this problem, first, the practical end that principlism allegedly accomplishes (ie, providing practical moral guidelines in a relatively ‘thick’ content, based on common morality) is frustrated, and, second, principlism makes itself the method of common morality de jure and of moral pluralism de facto. (shrink)

It is well known that, in classical theory, Liouville's theorem shows that if an ensemble of systems is distributed over a small element of volume in phase space, the ensemble fills a region of equal volume at all later instants of time. In quantum mechanics, the uncertainty principle is associated with the products of the errors in conjugate coordinates and momenta, and such products can be interpreted in terms of volume elements in phase space. Comparison of these two facts leads (...) to the assertion in the interesting volume on “Statistical Mechanics” recently published by J. E. and M. G. Mayer that “The Liouville theorem is essential for the complete understanding of the uncertainty principle. (shrink)

The review system on research with human participants in the Netherlands is characterised as a decentralised controlled and integrated peer review system. It consists of an independent governmental body, the Central Committee on Research Involving Human Subjects (or Central Committee), which regulates the review of research proposals by accredited Medical Research Ethics Committees (MRECs). The legal basis was founded in 1999 with the Medical Research Involving Human Subjects Act. The review system is a decentralised arrangement since most research proposal are (...) reviewed by the 30 accredited MRECs in the country. It is a controlled system in which the Central Committee is responsible for the accreditation and oversight of the MRECs and can make legally binding directives for these committees. The assessment of research proposals is an integrated peer review process in which all documents of the research file are reviewed by experts in one committee only. A small number of research proposals are assessed by the Central Committee and not by accredited MRECs. These proposals are on specific research categories such as gene therapy, cell therapy and embryo research. The review of research with surplus human embryos is regulated separately in the Embryos Act. The Central Committee provides support to the accredited MRECs and to researchers and sponsors. It is currently developing an internet portal to reduce the bureaucracy and make the review process more efficient and transparent. The Central Committee stimulates confidence on medical research in society by providing a public trial registry with core data on reviewed research proposals. (shrink)

Feedback control in neural systems is ubiquitous. Here we study the mathematics of nonlinear feedback control. We compare models in which the input is multiplied by a dynamic gain (multiplicative control) with models in which the input is divided by a dynamic attenuation (divisive control). The gain signal (resp. the attenuation signal) is obtained through a concatenation of an instantaneous nonlinearity and a linear low-pass filter operating on the output of the feedback loop. For input steps, the dynamics of gain (...) and attenuation can be very different, depending on the mathematical form of the nonlinearity and the ordering of the nonlinearity and the filtering in the feedback loop. Further, the dynamics of feedback control can be strongly asymmetrical for increment versus decrement steps of the input. Nevertheless, for each of the models studied, the nonlinearity in the feedback loop can be chosen such that immediately after an input step, the dynamics of feedback control is symmetric with respect to increments versus decrements. Finally, we study the dynamics of the output of the control loops and find conditions under which overshoots and undershoots of the output relative to the steady-state output occur when the models are stimulated with low-pass filtered steps. For small steps at the input, overshoots and undershoots of the output do not occur when the filtering in the control path is faster than the low-pass filtering at the input. For large steps at the input, however, results depend on the model, and for some of the models, multiple overshoots and undershoots can occur even with a fast control path. (shrink)

Results of two survey studies are presented. It is shown that attitudes of the public about "technology in general" are not stable and can easily be affected by how the subject is introduced. Eight areas of technology are compared on the basis of empirical relations in attitudinal judgments, in attribute ratings, in self- assigned importance weights of attributes, and in importance of reference groups and persons. On the basis of similarities in these four kinds of judgments, three clusters of technology (...) areas were identified: a cluster of modern reproductive technologies, an information cluster containing automation, computer, and communication technologies, and a cluster containing nuclear energy and military technology. The attitude toward "technology in general" can not be considered as an aggregation of attitudes toward these areas of technology: The relations between general attitude and specific attitudes are only moderate to negligible. (shrink)