The time taken to react voluntarily to a stimulus is far longer than can be accounted for by ordinary processes of nerve conduction and synaptic delay, and varies unpredictably from trial to trial. Though random, the distribution of reaction times usually follows a relatively simple law, which in turn can be explained by the LATER model, in which a decision signal, representing belief in the existence of the target, rises in response to incoming sensory evidence from an initial value to (...) a criterion level at which action is initiated. But the rate of rise fluctuates randomly from trial, to an extent that cannot be explained by sensory noise at the input. These conclusions, confirmed by recording from neurons in the frontal eye fields, suggest that the randomness of reaction time is due to a deliberate, gratuitous, neural process which confers certain biological advantages as well as having implications for general ideas about the nature of ‘free will'. (shrink)

Plato was born around 2,500 years ago. He lived in a small city-state in Greece and busied himself with the problems of his fellow Greeks, a people living in scattered cities around the Mediterranean and the Black Sea. In all he tried to do for the Greeks he failed. Why, then, should people in the modern world bother to read what he had to say? Does it make sense to go to a Greek thinker for advice on the problems of (...) an age so different from his own? To anyone who has questioned the relevance of Plato to the modern world Richard Crossman’s lively book provides a brilliant reply. The problems facing Plato’s world bear striking parallels to ours today, the author maintains, so who better to turn to than Plato, the most objective and most ruthless observer of the failures of Greek society. Crossman’s engaging text provides both an informed introduction to Greek ideas and an original and controversial view of Plato himself. (shrink)

Plato was born around 2,500 years ago. He lived in a small city-state in Greece and busied himself with the problems of his fellow Greeks, a people living in scattered cities around the Mediterranean and the Black Sea. In all he tried to do for the Greeks he failed. Why, then, should people in the modern world bother to read what he had to say? Does it make sense to go to a Greek thinker for advice on the problems of (...) an age so different from his own? To anyone who has questioned the relevance of Plato to the modern world Richard Crossman’s lively book provides a brilliant reply. The problems facing Plato’s world bear striking parallels to ours today, the author maintains, so who better to turn to than Plato, the most objective and most ruthless observer of the failures of Greek society. Crossman’s engaging text provides both an informed introduction to Greek ideas and an original and controversial view of Plato himself. (shrink)

Plato was born around 2,500 years ago. He lived in a small city-state in Greece and busied himself with the problems of his fellow Greeks, a people living in scattered cities around the Mediterranean and the Black Sea. In all he tried to do for the Greeks he failed. Why, then, should people in the modern world bother to read what he had to say? Does it make sense to go to a Greek thinker for advice on the problems of (...) an age so different from his own? To anyone who has questioned the relevance of Plato to the modern world Richard Crossman’s lively book provides a brilliant reply. The problems facing Plato’s world bear striking parallels to ours today, the author maintains, so who better to turn to than Plato, the most objective and most ruthless observer of the failures of Greek society. Crossman’s engaging text provides both an informed introduction to Greek ideas and an original and controversial view of Plato himself. (shrink)

Science in a Free Society is the sequel to Feyerabend's earlier iconoclastic, provocative book, Against Method. As he states in the preface: "Like the earlier book this volume has one aim: to remove obstacles intellectuals and specialists create for traditions different from their own and to prepare the removal of the specialists themselves from the life centers of society". The book is divided into three parts: Part 1 resumes the argument presented in Against Method; part 2 extends the implications of (...) that position to the conception of a "free society"; and part 3 contains a revealing autobiographical account along with answers to his critics--no less inhibited in style than his earlier book. Thus the conclusions in this volume should be viewed as an extension of the arguments of the previous essay. (shrink)

Annotation A scholarly edition of a work by Adam Smith. The edition presents an authoritative text, together with an introduction, commentary notes, and scholarly apparatus.

To localize wheat ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and (...) least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin. (shrink)

(1884). ANNUAL ADDRESS READ BEFORE THE “SOUTH AFRICAN PHILOSOPHICAL SOCIETY,”. Transactions of the South African Philosophical Society: Vol. 4, No. 1, pp. xxx-liii.

Are restrictive measures and duties to care ethically reasonably acceptable to faith-based organizations? This study describes the perceptions of individually interviewed spiritual leaders of the disease control measures used during the recent SARS outbreak in Toronto. Four central themes were identified: the relationship between religious obligation and civic responsibilities; the role of faith-based organizations in supporting public health restrictive measures; the reciprocal obligations of public health and religious communities during restrictions; and justifiable limits to duties to care. We conclude that, (...) within certain constraints, spiritual leaders find restrictive measures ethically reasonable and that spiritual leaders can play an important role during pandemic and epidemic control planning. Public health officials should therefore include them in the early and ongoing deliberations of the criteria and logistics for implementation during public health emergencies. (shrink)

Rita Bottino,1 Santosh Nagaraju,2 Vikas Satyananda,2 Hidetaka Hara,2 Martin Wijkstrom,2 Massimo Trucco,1 David KC Cooper2 1Institute of Cellular Therapeutics, Allegheny Health Network, 2Thomas E Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA: Diabetes mellitus is increasing worldwide. Type 1 diabetes can be treated successfully by islet allotransplantation, the results of which are steadily improving. However, the number of islets that can be obtained from deceased human donors will never be sufficient to cure more than a very (...) small percentage of patients who might benefit from transplantation. Although there are some differences in glucose metabolism between pigs and humans, the use of pigs could provide an unlimited supply of islets, and the insulin produced would undoubtedly control glucose levels. Transplantation of islets into the portal vein results in islets residing in the liver; however, an early inflammatory response and rejection remain problematic, even when the recipient is receiving immunosuppressive therapy. In the long term, immunosuppressive drugs may exhibit toxicities to patients and specifically harm the islet cells. In contrast, encapsulation techniques provide islets with a physical barrier that prevents antibodies binding to the islet graft while still allowing insulin to be released into the recipient's circulation; in theory, patients receiving encapsulated grafts might not require exogenous immunosuppressive therapy. Nonhuman primates with encapsulated pig islet transplants have remained insulin-independent for several weeks, but long-term efficacy remains uncertain. Furthermore, techniques are now available to knock out genes from the pig and/or insert human genes, thus rendering the antigenic structure of pigs closer to that of humans, and providing protection from the human immune response. Islet transplantation from genetically engineered pigs has been followed by insulin independence in a small number of nonhuman primates for greater than 1 year. Neonatal islets have some advantages over adult islets in that they are easier to isolate and culture, and have the ability to proliferate during the first few months after transplantation. In 2009, the International Xenotransplantation Association set up a group to encourage and advise on clinical trials of pig islet xenotransplantation; this group's guidelines are discussed. Clinical trials of encapsulated pig islets are already under way. Keywords: diabetes, islets, pancreatic, pig, xenotransplantation. (shrink)

Biologically motivated computing seeks to transfer ideas from the biosciences to computer science. In seeking to make transfers it is helpful to be able to appreciate the metaphors which people use. This is because metaphors provide the context through which analogies and similes are made and by which many scientific models are constructed. As such, it is important for any rapidly evolving domain of knowledge to have developments accounted for in these terms. This paper seeks to provide one overview of (...) the process of modelling and shows how it can be used to account for a variety of biologically motivated computational models. Certain key ideas are identified in the subsequent analysis of biological sources, notably, systemic metaphors. Three important aspects of biological thinking are then considered in the light of computer science applications: biological organization, the cell, and models of evolution. The analysis throughout the paper is descriptive rather than formalized so that a large variety of potential applications may be considered. (shrink)