In the recent past, several papers have pointed to the possibility that tumour removal generates a permissive environment in which tumour growth is potentiated. This phenomenon has been coined “perioperative tumour growth” and whilst it represents a departure in terms of our attitude to the surgical process, this concept was first hinted at by Paget1Sir James Paget (1814–1899) was a surgeon and physiologist who is widely held (along with Rudolph Virchow) to be the father of the science of pathology. Paget (...) described Paget's disease of the nipple as well as Paget's disease of bone. himself. Despite this, the time interval immediately before and after cancer surgery (i.e. the perioperative period) remains an underutilised interval during which chemotherapeutic regimens are rarely implemented. Herein, we present a summarised review of the literature that supports the concept that tumour removal may potentiate the growth of residual neoplastic disease. We also outline current knowledge regarding underlying mechanisms and in this manner highlight potential therapeutic entry points. Finally, we emphasise the urgent need for trials of agents that could protect patients against the harmful host–tumour interactions that may occur during the perioperative period. BioEssays 28: 433–437, 2006. © 2006 Wiley Periodicals, Inc. (shrink)

Using covariant derivatives and the operator definitions of quantum mechanics, gauge invariant Proca and Lehnert equations are derived and the Lorenz condition is eliminated in U(1) invariant electrodynamics. It is shown that the structure of the gauge invariant Lehnert equation is the same in an O(3) invariant theory of electrodynamics.

Dear Editor, -/- One of the recent changes in the UK cabinet, after Liz Truss became the Prime Minister, was that Dr Therese Coffey become the new Health Secretary. Some news outlets were quick to point out her anti-abortion stance (see e.g. (1–3)) and that this, according to them, might be a problem. While pro-lifers might not completely rejoice over this situation as Coffey stated that ‘she wouldn’t “seek to undo” abortion laws’(3), I do not wish to focus (...) here on speculating on the future status of UK abortion legislation. Rather, I wish to focus on some statements quoted by the media as made by Clare Murphy, chief executive of the British Pregnancy Advisory Service (BPAS), who stated that: (2,4) -/- ‘Earlier this year, our new Health Secretary voted to revoke access to at-home abortion care, and recriminalise women who end their own pregnancies without the approval of two doctors.’ ‘In doing so, Therese Coffey voted against the advice of leading medical bodies.’ ‘To have a health secretary who would place their personal beliefs above expert clinical guidance is deeply concerning.’ -/- Coffey is a Catholic, and this brings back to mind some of the aspects of the debate surrounding conflicts of interest in bioethics. There have been, for example, discussions and proposals that having a religious belief should be declared as a conflict of interest.(5,6) But something seems to be missing in these portrayals of conflict of interest and the disagreement between Coffey and these ‘leading medical bodies’. If we regard financial conflicts of interests as the classical case of such conflicts that is used as a reference to other types of conflicts of interest,(5,6) then why do we not see the media complaining that ‘leading medical bodies’ support procedures that will give them more work oppor-tunities and improve their financial stability? To paraphrase Murphy who (according to the BBC 'said while politicians were entitled to their own views on abortion, what mattered was whether their "personal convictions stand in the way of women's ability to act on their own”. (4) perhaps ‘BPAS and the leading medical bodies are entitled to considerations of their financial interests, but what matters is whether the advice they give is clinically sound and founded in the principles of ethical clinical practice. In Matthew 6:24 Our Lord said that one cannot serve two masters, so perhaps we should not be so concerned with Coffey consulting her conscience, but rather scrutinise clinical institutions. (shrink)

Global properties of canonical derivability predicates in Peano Arithmetic) are studied here by means of a suitable propositional modal logic GL. A whole book [1] has appeared on GL and we refer to it for more information and a bibliography on GL. Here we propose a sequent calculus for GL and, by exhibiting a good proof procedure, prove that such calculus admits the elimination of cuts. Most of standard results on GL are then easy consequences: completeness, decidability, finite model property, (...) interpolation and the fixed point theorem. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:NECESSARY PROPOSITIONS AND THE SQUARE OF OPPOSITION MARK ROBERTS University of Rhode Island Kingston, Rhode Island IT IS COMMONPLACE to define contradictory, contrary, and subcontrary propositions in the following way: contradictory propositions cannot both be true and cannot both be false; contrary propositions cannot both be true but can both be false; and subcontrary propositions can both be true but cannot both be false. In his Introduction to Logic (...) 1 Irving Copi raises a problem with two of these definitions which he believes forces him to limit the range of propositions which can be used in the square of opposition. Since contrary propositions can both be false, but the falsity of a necessarily true proposition is not possible, a necessarily true proposition has no contrary. Therefore, only contingent propositions can be contraries. Subcontrary propositions can both be true, but the truth of a necessarily false proposition is not possible.2 This problem is rarely raised in other logic texts, but, it is interesting to note, it is mentioned by a number of neoscholastic philosophers, for example, P. Nicholas Russo,3 Rev. H. Grenier,4 1 Irving M. Copi, Introduction to Logic (New York: Macmillan, 1986), pp. 178-179. Copi first introduced this problem in the fifth edition of his work on the basis of an article by David H. Sanford entitled " Contraries and Subcontraries,'' Nous 2 (1968) : 95-96. Sanford argues that the most reasonable way to resolve the problem of necessary propositions is to assume that contingent propositions comprise the square of opposition. 2 Copi, pp. 178-179. 8 Nicholas Russo, Summa Philosophica (Boston: Apud Marlier et Socios, 1[;85), p. 23. 4 Henri Grenier, Thomistic Philosophy, Vol. I (Charlottetown, Canada: St. Dunstan's University, 1950), p. 69. 427 428 MARK ROBERTS G. Sanseverino,5 Jacques Maritain,6 F.-X. Maquart,7 P. Coffey,8 and others.9 (It is also mentioned by Bishop Whately.10 ) Each of these philosophers makes necessarily true or false propositions an exception to the definition of contrary and subcontrary propositions. The reason is they and Copi interpret the definitions of contrary and subcontrary propositions to mean that the falsity of each contrary proposition is possible and the truth of each subcontrary proposition is possible. It should be mentioned, however, that the position of the philosophers cited above is not entirely the same as Copi's. Copi reasons that these definitions imply that necessary propositions have no contrary or subcontrary. The other philosophers believe that necessary propositions can be contraries and subcontraries. Thus, in the case of necessary propositions contrary and subcontrary propositions are, instead, defined merely in terms of their quantity and quality, not by whether or not they can both be false or can both be true. In fact, Coffey and some of the other philosophers cited above assert that, when the propositions composing the square are necessary, one can infer the truth of the universal from the truth of 5 Gaietano Sanseverino, Philosophia Christiana, Vol. II (Neapoli: Vincentii Manfredi, 1862), pp. DCCXXXVIII ff. 6 J. Maritain, An Introduction to Logic (London: Sheed & Ward, 1937), p. 135, notes 1 & 2. 7 F.-X. Maquart, Elementa Philosophiae, Vol. I (Parisiis: Andreas Blot, 1937)' p. 126 ff. 8 P. Coffey, The Science of Logic, Vol. 1 (New York: Longmans, Green & Co., 1918), p. 225, 226. 9 Joseph Gredt, Elementa Philosophiae, Vol. I (Friburgi: Herder, 1929), p. 46, notes 1 & 2; Sylvester J. Hartman, A Textbook of Logic (New York: American Book Co., 1936), p. 162 ff; Roland Houde and Jerome J. Fischer, Handbook of Logic (Dubuque, Iowa: Wm. C. Brown Co., 1954), p. 61; Eduard Hugon, Cursus Philosophiae Thomisticae, Vol. I (Parisiis: P. Lethielleux n.d), p. 155; Dennis C. Kane, Logic: The Art of Predication and Inference (Providence: Providence College Press, 1978), p. 98 ff; Francis P. Siegfried, Essentialia Philosophiae (Philadelphia: Dolphin Press, 1927), p. 25; Francis Varvello, Minor Logic, trans. and supplemented Arthur D. Fearon (San Francisco: Univ. of San Francisco Press, 1933), p. 73 ff. 10 Richard Whately, Elements of Logic (Boston: James Munroe & Co., 1854), p. 77 ff. PROPOSITIONS AND THE SQUARE OF OPPOSITION 429 the particular and the falsity of the particular from the falsity of the universal.11 Maritain maintains that in the case... (shrink)

One of the areas of concern raised by cross-border reproductive travel regards the treatment of women who are solicited to provide their ova or surrogacy services to foreign consumers. This is particularly troublesome in the context of developing countries where endemic poverty and low standards for both medical care and informed consent may place these women at risk of exploitation and harm. We explore two contrasting proposals for policy development regarding the industry, both of which seek to promote ethical outcomes (...) and social justice: While one proposal advocates efforts to minimize cross-border demand for female reproductive resources through the pursuit of national self-sufficiency, the other defends cross-border trade as a means for meeting the needs of vulnerable groups. Despite the conflicting objectives of the proposed strategies, the paper identifies common values and points of agreement between the two, including the importance of regulations to safeguard those providing ova or surrogacy services. (shrink)

The principle of “equivalence of care” in prison medicine is a principle by which prison health services are obliged to provide prisoners with care of a quality equivalent to that provided for the general public in the same country. It is cited in numerous national and international directives and recommendations.The principle of equivalence is extremely relevant from the point of view of normative ethics but requires adaptation from the point of view of applied ethics. From a clinical point of view, (...) the principle of equivalence is often insufficient to take account of the adaptations necessary for the organization of care in a correctional setting. The principle of equivalence is cost-effective in general, but has to be overstepped to ensure the humane management of certain special cases. (shrink)

The current Ebola epidemic has presented challenges both medical and ethical. Although we have known epidemics of untreatable diseases in the past, this particular one may be unique in the intensity and rapidity of its spread, as well as ethical challenges that it has created, exacerbated by its geographic location. We will look at the infectious agent and the epidemic it is causing, in order to understand the ethical problems that have arisen.

Relatively congruence regular quasivarieties and quasivarieties of logic have noticeable similarities. The paper provides a unifying framework for them which extends the Blok-Pigozzi theory of elementarily algebraizable (and protoalgebraic) deductive systems. In this extension there are two parameters: a set of terms and a variable. When the former is empty or consists of theorems, the Blok-Pigozzi theory is recovered, and the variable is redundant. On the other hand, a class of membership logics is obtained when the variable is the only (...) element of the set of terms. For these systems the appropriate variant of equivalent algebraic semantics encompasses the relatively congruence regular quasivarieties. (shrink)

This book attempts, through a series of interpretive discussions, to confront a number of well-known perplexities in their structural form of disjunctive moments, of interpretive contexts of 'this is' and 'this is not.'.

Ecological theory is built upon assumptions about the fundamental nature of organism-environment interactions. We argue that two mutually exclusive sets of such assumptions are available and that they have given rise to alternative approaches to studying ecology. The fundamentally different premises of these approaches render them irreconcilable with one another. In this paper, we present the first logical formalisation of these two paradigms.The more widely-accepted approach - which we label the demographic paradigm - includes both population ecology and community ecology (...) (synecology). Demographic ecology assumes that the environment is relatively stable and that biotic processes, governed predominantly by resource availability, are the most important of ecological and evolutionary influences. Moreover, ecological processes are assumed to translate into directional selection pressures that drive significant evolutionary change on a local scale through the process of optimisation. (shrink)

Social inequalities in health in the UK persist despite attempts to reduce them. We argue that work and pensions constitutes an area of intervention where there is potential to make change happen. We propose that workers who are exposed to significant health risks through their occupation should be allowed to draw their state pension earlier, based on a minimum number of years in the workforce. We model this proposal on similar policies in other European countries. In our modification, the pension (...) age and the retirement age would be separated, such that workers can receive a state pension whether or not they choose to continue working. This arrangement may encourage workers either to reduce their working hours or to change to less demanding or harmful work. The health of these workers would thereby benefit from reduced exposure to a harmful work environment, reduced stress and more opportunities for rest and relaxation. However, it has also been suggested that retirement is bad for mental health. In response, our proposal enables workers to phase in full retirement over a period of part-time work, and we believe that this would counter any potential negative effects on health caused by retirement. (shrink)

John Rawls’ use of a contractarian strategy for justifying basic principles of justice has raised the hope that a similar strategy might work for a theory of right and moral principles generally. I want to show that this hope cannot be fulfilled.In what follows I interpret contractarianism in a Rawlsian way on the grounds that his is the most plausible version of the doctrine we are likely to get. I am not however concerned with the details of Rawls’ argument for (...) justice but instead with an idea that appears to underlie the contractarian strategy. In order to avoid the complications of Rawlsian exegesis, I choose to discuss the doctrine as it might be used to justify a moral principle of mutual assistance and not as Rawls in fact uses it to justify principles of justice. (shrink)