Adolescence methamphetamine use is an issue of considerable concern due to its correlation with later delinquency, divorce, unemployment and health problems. Understanding how adolescents initiate methamphetamine abuse is important in developing effective prevention programs. We formulate a mathematical model for the spread of methamphetamine abuse using nonlinear ordinary differential equations. It is assumed that susceptibles are recruited into methamphetamine use through imitation. An epidemic threshold value, Ra\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal {R}}_a$$\end{document}, termed the abuse reproduction (...) number, is proposed and defined herein in the drug-using context. The model is shown to exhibit the phenomenon of backward bifurcation. This means that methamphetamine problems may persist in the population even if Ra\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal {R}}_a$$\end{document} is less than one. Sensitivity analysis of Ra\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathcal {R}}_a$$\end{document} was performed to determine the relative importance of different parameters in methamphetamine abuse initiation. The model is then fitted to data on methamphetamine users less than 20 years old reporting methamphetamine as their primary substance of abuse in the treatment centres of Cape Town and parameter values that give the best fit are chosen. Results show that the proportion of methamphetamine users less than 20 years old reporting methamphetamine as their primary substance of abuse will continue to decrease in Cape Town of South Africa. The results suggest that intervention programs targeted at reducing adolescence methamphetamine abuse, are positively impacting methamphetamine abuse. (shrink)

The encounter between Socrates and Thrasymachus in Republic I is notoriously baffling. Most of what is said seems straightforward, and the issues at stake are ones of common concern, but the argument remains elusive. The purpose of this paper is to investigate the nature and grounds of this elusiveness, and to show that some of it can be dispelled by a sufficiently free-ranging exegesis that bears in mind the general character of Plato’s writing.

In lieu of an abstract, here is a brief excerpt of the content:THE INCOMMUNICABILITY OF HUMAN PERSONS JOHN F. CROSBY, III Franciscan University of Steubenville Steubenville, Ohio I PROPOSE TO explore the idea that persons do not exist as replaceable specimens of or as mere instances of an ideal or type, but rather exist in some sense for their own sakes, each existing as incommunicably his or her own.1 I undertake this study in the conviction that the incommunicability of persons (...) is profoundly characteristic for them precisely as persons, and has a major role to play in any philosophy of the person. And there is an entirely different reason which attracts me to this subject. I think that most of what I have to say here can find acceptance across a broad spectrum of philosophical positions. At a time when thinkers are increasingly suspicious of universally valid truth about man, when many of them think that a vision of man is proper only to some tradition and valid only within that tradition and not beyond it, one can offer a salutary challenge to one's contemporaries by showing a centrally important truth about persons which, as I say, can be accepted by philosophers coming from the most various points of view. Suppose that you were to minimalize the death of someone by saying that at least the human species did not die with him or her, as if the immortality of the species more than compensated for the mortality of this individual : everyone understands that you would thereby radically depersonalize the deceased. Or suppose that you were grieving over the death of someone dear to you, and a friend tried to comfort you with the thought that the 1 My thanks to Josef Seifert, William Frank, Damian Fedoryka, and Katryna Fedoryka for their comments on earlier drafts of this study. The text of this article forms Chapter Two of my book, Essay on Personal Selfhood, which is close to completion. 403 404 JOHN F. CROSBY, III particular excellences of the deceased, which awakened your love, also exist in other human beings who are still living, as if you could continue to love in them what you had loved in the deceased. Again, everyone understands that if you treat people having excellences as if they were replaceable specimens of those excellences, then you lose your grip on them as persons. But why is this? Why is personhood driven out of human beings as soon as their species-membership, or their particular excellences, are thought to predominate in them? What is that incommunicability of each person which is obscured as soon as persons are thought to be only specimens? One commonly thinks that this aspect of personal selfhood has been recognized only in modern thought; in fact it was recognized already by St. Thomas Aquinas. Creatura autem rationalis divinae providentiae substat sicut secundum se gubernata et provisa, non solum propter speciem, ut aliae corruptibiles creaturae : quia individuum quod gubernatur solum propter speciem, non gubernatur propter seipsum; creatura autem rationalis propter seipsam gubernatur, ut ex dictis manifestum est. Sic igitur solae rationales creaturae directionem a Deo ad suos actus accipiunt non solum propter speciem, sed secundum individuum.2 Notice that Aquinas teaches here the metaphysical ultimacy of personal incommunicability; it exists even before God in the sense 2 " Now, a rational creature exists under divine providence as a being governed and provided for in himself, and not simply for the sake of his species, as is the case with other corruptible creatures. For the individual that is governed only for the sake of the species is not governed for its own sake, but the rational creature is governed for his own sake, as is clear from what we have said (ch. 112). And so, only rational creatures receive direction from God in their acts, not only for the species, but for the individual." Summa Contra Gentiles, III, ch. 113 (Bourke translation). By the way, Chapters 111-114 of Book III seem to me to constitute the most " personalist " passage' in the entire corpus of St. Thomas. The modern reader sees to his amazement that St. Thomas here has already made his own the Kantian idea that each person in a sense exists for his... (shrink)

In responding to Ms Rowell’s commentary on her original paper the author points out that the job of all bioethicists, namely, speaking truth to power, is a daunting task which is unlikely to succeed “if we do not learn to ask for and to accept, to offer and to provide, moral support and meaningful help.”In my article “The Olivieri debacle: where were the heroes of bioethics?”1 I make four comments about Ms Rowell’s involvement in the case. In my first comment (...) relating to Ms Rowell, I suggest that a careful reader of the Naimark report could reasonably conclude “that the role of bioethics in helping to resolve the controversy was, at best, very limited”. In reaching this conclusion, I relied on the findings of the two official reports/inquiries about this case. Though the two reports reach different conclusions about the case, there appears to be agreement on the very limited role of bioethics. As noted in my original article, in the 160 page Naimark report there are but a few paragraphs about bioethics and Ms Rowell’s role in the Olivieri case. This is surprising, and I say as much in my article. In the 540 page report of the Committee of Inquiry, which Ms Rowell describes as “a review that I believe to provide a public report of integrity”, little more detail is provided regarding Ms Rowell’s role. I included all references to Ms Rowell from the first report in the original article. I did not do so with the second report. This was not done to diminish any contribution Ms Rowell might have made. In my view, no new evidence germane to the points I wanted to make was provided in the text that I did not include in my article.In …. (shrink)

Cet article explore le moment où le thème de la formation professionnelle des femmes, longtemps négligé, s’invite dans le débat public sous la pression d’organisations internationales et nationales. À partir d’un corpus de documentaires et reportages filmés diffusés à la télévision française entre 1958 et 1973 et de différents fonds d’archives, il analyse l’émergence d’une figure de femme en formation professionnelle féminine, celle d’une femme au foyer souhaitant (re)trouver un travail après une longue interruption pour raison familiale. Cette figure en (...) vient à éclipser toute autre image, notamment celle de la salariée en formation. Les documents filmés sont pris ici comme des révélateurs des manières de penser la formation et son public dans une période de transition historique, celle d’une remise en question des rôles socio-sexuels en particulier vis-à-vis du travail. (shrink)

Much of Essler''s work has been devoted to bringing science andphilosophy together for the purpose of conceptual clarification. Oneparticularly interesting area for such cooperation between science andphilosophy has been relativity theory. In this paper I will consider oneinstance of such interplay: the transformation that our notions of rotationand rigidity have undergone in general relativity and what this process canteach us. I will start by saying a little about the physics of the situation andthen go on to some philosophical observations about (...) meaning and theory. (shrink)

Open peer commentary on the article “Ontology, Reality and Construction in Niklas Luhmann’s Theory” by Krzysztof C. Matuszek. Upshot: The question of whether contingency can be limited concerns the foundations of sociological systems theory as a theory of cognition. This commentary argues that while such limits may seem plausible and apparent at first, they would consequentially give rise to an ontological notion of society within society. Rather, the commentary proposes to understand the limits identified in the target article as social (...) functions structuring expectations in situations of double contingency. (shrink)

The role played by objectivity in continuum physics is reexamined in an attempt to establish fully its deep connection with classical and relativistic time derivatives. The way of distinguishing one element in the class of objective time derivatives may depend on the particular problem of interest; this is emphasized in conjunction with material relaxation phenomena described via hidden variable evolution equations.

§ 1. The dates for Peisistratus’ reigns and exiles in the Athenaion Politeia, as given in the papyrus, which is the sole authority for the text, are as follows.

Response to the Commentary on ‘The View from Within’ The numerous commentators to this Special Issue have greatly enhanced its focus and usefulness. We thank them all very sincerely for their efforts. Within the restricted space of this rejoinder we cannot respond in detail to all the issues raised. Instead, we shall concentrate first on some fundamental criticisms.The remaining additions and complementary ideas will only be touched on briefly, merely to see them in perspective. We shall start with our two (...) main critics of the global enterprise, Baars and Nixon. They both offer arguments that our enterprise is misguided, but their arguments fall on two opposite extremes: empirical and hermeneutical. (shrink)