DNA helicases catalyze the disruption of the hydrogen bonds that hold the two strands of double‐stranded DNA together. This energy‐requiring unwinding reaction results in the formation of the single‐stranded DNA required as a template or reaction intermediate in DNA replication, repair and recombination. A combination of biochemical and genetic studies have been used to probe and define the roles of the multiple DNA helicases found in E. coli. This work and similar efforts in eukaryotic cells, although far from complete, have (...) established that DNA helicases are essential components of the machinery that interacts with the DNA molecule. (shrink)

Moral reasoning traditionally distinguishes two types of evil:moral and natural. The standard view is that ME is the product of human agency and so includes phenomena such as war, torture and psychological cruelty; that NE is the product of nonhuman agency, and so includes natural disasters such as earthquakes, floods, disease and famine; and finally, that more complex cases are appropriately analysed as a combination of ME and NE. Recently, as a result of developments in autonomousagents in cyberspace, a new (...) class of interesting and importantexamples of hybrid evil has come to light. In this paper, it is called artificial evil and a case is made for considering it to complement ME and NE to produce a more adequate taxonomy. By isolating the features that have led to the appearance of AE, cyberspace is characterised as a self-contained environment that forms the essential component in any foundation of the emerging field of Computer Ethics. It is argued that this goes someway towards providing a methodological explanation of whycyberspace is central to so many of CE's concerns; and it isshown how notions of good and evil can be formulated incyberspace. Of considerable interest is how the propensity for anagent's action to be morally good or evil can be determined evenin the absence of biologically sentient participants and thusallows artificial agents not only to perpetrate evil but conversely to `receive' or `suffer from'it. The thesis defended is that the notion of entropy structure,which encapsulates human value judgement concerning cyberspace ina formal mathematical definition, is sufficient to achieve thispurpose and, moreover, that the concept of AE can be determinedformally, by mathematical methods. A consequence of this approachis that the debate on whether CE should be considered unique, andhence developed as a Macroethics, may be viewed, constructively,in an alternative manner. The case is made that whilst CE issues are not uncontroversially unique, they are sufficiently novel to render inadequate the approach of standard Macroethics such as Utilitarianism and Deontologism and hence to prompt the search for a robust ethical theory that can deal with them successfully. The name Information Ethics is proposed for that theory. Itis argued that the uniqueness of IE is justified by its beingnon-biologically biased and patient-oriented: IE is anEnvironmental Macroethics based on the concept of data entityrather than life. It follows that the novelty of CE issues suchas AE can be appreciated properly because IE provides a newperspective. In light of the discussion provided in this paper, it is concluded that Computer Ethics is worthy of independent study because it requires its own application-specific knowledge and is capable of supporting a methodological foundation, Information Ethics. (shrink)

Although the theory of definability had many important antecedents—such as the descriptive set theory initiated by the French semi-intuitionists in the early 1900s—the main ideas were first laid out in precise mathematical terms by Alfred Tarski beginning in 1929. We review here the basic notions of languages, explicit definability, and grammatical complexity, and emphasize common themes in the theories of definability for four important languages underlying, respectively, descriptive set theory, recursive function theory, classical pure logic, and finite-universe logic. We review (...) the history of previous studies of the similarities and differences in the theories of definability of the first three of these four languages. A seminal role leading toward unification of the theories has been played by the separation principles introduced by Nikolai Luzin in 1927. Emphasizing analogies and driving toward further unification embracing finite-universe logic we concentrate on a simple example—the first and second separation principles for existential-universal first-order sentences . Using this as a test case for the fundamental problem of how to “finitize” arguments in classical pure logic to the finite-universe case, we are led to the analogous negative solution by using the theory of certain special graphs: a graph is - special for any positive integers m , n , p , q iff it is bipartite with m red points and n blue points and for every p -tuple of red points there is a blue point to which they are all connected . As an aside we introduce for further study a natural “Ramseyesque” increasing sequence A of positive integers, where A is the least positive integer n for which an -special graph exists. (shrink)

Is logic normative for reasoning? In the wake of work by Gilbert Harman and John MacFarlane, this question has been reduced to: are there any adequate bridge principles which link logical facts to normative constraints on reasoning? Hitherto, defenders of the normativity of logic have exclusively focussed on identifying adequate validity bridge principles: principles linking validity facts—facts of the form 'gamma entails phi'—to normative constraints on reasoning. This paper argues for two claims. First, for the time being at least, Harman’s (...) challenge cannot be surmounted by articulating validity bridge principles. Second, Harman’s challenge can be met by articulating invalidity bridge principles: principles linking invalidity facts of the form 'gamma does not entail phi' to normative constraints on reasoning. In doing so, I provide a novel defence of the normativity of logic. (shrink)

The purpose of this brief introduction is to describe the origin of the papers here presented and to acknowledge the help of some of the many individuals who were involved in the preparation of this volume. Of the eighteen papers, nine stem from the annual fall colloquium of the Depart ment of Philosophy at the University of Western Ontario held in London, Ontario from November 10 to November 12, 1967. The colloquium was entitled 'Philosophical Logic'. After some discussion, the editors (...) decided to retain that title for this volume. Von Wright's paper 'On the Logic and Ontology of Norms' is printed here after some revision. A. R. Anderson commented on the paper at the colloquium, but his comments here are based upon the revised version of the von Wright paper. The chairman of the session at which von Wright's paper was read and discussed was T. A. Goudge. Aqvist's paper 'Scattered Topics in Interrogative Logic', and Belnap's comments, 'Aqvist's Cor rections-Accumulating Question-Sequences', are printed as delivered. The chairman of the Aqvist-Belnap session was R. E. Butts. Wilfrid Sellars' paper 'Some Problems about Belief' is printed as delivered at the col loquium, but 'Quantifiers, Beliefs, and Sellars' by Ernest Sosa is a revision of his comments at the colloquium. That session was chaired by G. D. W. Berry. Ackermann's paper 'Some Problems oflnductive Logic', as well as Skyrms' comments, are printed as delivered. (shrink)

This presentation of the main phases and features of political thought in the sixteenth century is based on an exhaustive study of contemporary writings in Latin, English, French, German and Italian. The book is divided into four parts. The first part deals with the new thought of Protestantism. The rest describes special ideas that emerged in England, France and Italy.

Biobanking of patient-derived materials is routine in health care, research, and public health emergencies. Ethical guidelines for biobanking address concerns including some about genetic materials, informed consent, confidentiality, regulatory environments, and standards of governance. This chapter identifies some limitations of existing guidelines that were apparent to one author during an Ebola outbreak, and specifies five ethical concerns about biobanking that warrant additional attention: misconceptions about biobanking, unknown consequences for donors, socioeconomic inequities that compound vulnerabilities, lasting and proportional benefits in North-South (...) research, and contextual challenges to disclosure and understanding. These affect patients, donors, health systems, research, and policy, and are amplified during public health emergencies. (shrink)

When philosophers put forward claims for or against 'property', it is often unclear whether they are talking about the same thing that lawyers mean by 'property'. Likewise, when lawyers appeal to 'justice' in interpreting or criticizing legal rules we do not know if they have in mind something that philosophers would recognize as 'justice'. J. W. Harris here examines the legal and philosophical underpinnings of the concept of property and offers a new analytical framework for understanding property and justice.