La diffusion d'une innovation portant les germes de son plafonnement: la réutilisation des hémodialyseurs au Québec

Sommaire: L'objectif de cette recherche est d'identifier les facteurs de diffusion d'une innovation ‐ la réutilisation des hémodialyseurs (rh) ‐ ainsi que de son plafonncment marqué par la controverse, à travers les motivations et stratégies des groupes d'acteurs clés. Plus particulièrement, cette étude vise à situer le rôle de la “ médecine fondée sur des données probantes ”dans la dynamique de la diffusion de cette innovation. Nous partons du constat que la rh est une pratique reconnue pour les économies qu'elle génère tout en étant perçue par certains comme risquée pour la santé des usagers et du personnel. Les résultats de notre étude montrent que la diffusion de la rh au Québec, loin d'avoir pris son assise sur des données empiriques solides, a plutôt résulté de comportements sociaux d'imitation à la faveur de contacts directs entre des centres de dialyse voisins qui subissaient alors de fortes pressions de leurs autorités afin de réduire leurs dépenses. Cependant, l'ampleur des investissements nécessaires à l'introduction de cette pratique, la perspective de devoir négocicr I'achat de matériel dédiéà la rh auprès d'un monopole, ainsi que les stratégies commerciales de fournisseurs peu motivés à promouvoir la vente de matériel de rh au détriment de celle, plus lucrative, d'hémodialyseurs en grande quantité (lorsque non réutilisés), ont grandement réduit l'attrait économique dc la rh aux yeux des dirigeants de centres de dialyse. L'incapacité des données empiriques à endiguer les craintes soulevées par les risques associés à la rh a eu la double conséquence (1) dc mener au plafonnement de cette activité et (2) d'induire des centres de dialysc qui effectuaient déjà la rh à se doter d'une gestion envers les patients basée sur la non transparence et la contrainte. Sur le plan conceptuel, les résultats de cette étude montrent que ce n'est que dans la mesure où les facteurs sociaux et d'intérêts (dynamiquc institutionnelle) sont pris en compte et qu'ils convergent avec les critères de rationalité technique, qu'une innovation améliore ses chances de se diffuser et de s'enraciner dans une organisation. Considérant ces conclusions, quelques propositions sont énonées dans le but d'améliorer le potentiel d'implantation de la rh en facilitant la prise en compte des données empiriques dans les centres de dialyse, tout en leur procurant un meilleur rapport de force vis‐à‐vis leurs fournisseurs et afin que les patients et le personnel clinique y trouvent davantage leur intérêt. Abstract: The purpose of this research is to identify the factors in the diffusion of an innovation ‐ hemodialyzer re‐use ‐ and the controversy surrounding the levelling off of its use, by looking at the motivations and strategies of key actors. More particularly, this study focuses on the role of “evidence‐based medicine” in the diffusion of this innovation. Starting with the observation that hemodialyzer re‐use is recognized for its cost‐savings while being perceived by some to be a health risk for both users and staff, our findings show that diffusion of this practice in Quebec, far from being based on solid empirical data, was instead influenced by the social phenomenon of imitation that resulted from direct contact with local dialysis centres that were at the time under great pressure from their management to reduce expenditures. The cost‐savings of hemodialyzer re‐use for the people managing the dialysis centres was, however, greatly reduced by several factors: the considerable investments needed to introduce this practice; the prospects of having to negotiate with a monopoly to purchase the hemodialyzer‐dedicated equipment; and the commercial strategies of suppliers who have little interest in promoting the sale of equipment for hemodialyzer re‐use over the more lucrative sale of large quantities of hemodialyzers (when not re‐used). The ineffectiveness of empirical data in allaying fears of the risks associated with the practice of hemodialyzer re‐use has had the dual effect of 1) causing this activity to level off, and 2) causing dialysis centres already involved in hemodialyzer re‐use to adopt an approach to patient management that is based on non‐transparency and constraint. On the conceptual level, our findings show that the likelihood of an organization adopting an innovation increases when social factors and interest factors (such as the institutional dynamic) are taken into account and align with criteria of technical rationality. Given these conclusions, we put forward some proposals for improving the potential of hemodialyzer re‐use by facilitating the dialysis centres' consideration of empirical data. As well, our proposals are aimed at obtaining a stronger position for the centres with regard to their suppliers and at ensuring that both patients and clinic staff benefit more from the practice of hemodialyzer re‐use.     

Accumulation of explosives in hair--Part 3: Binding site study

This study extends previous work on the sorption of explosives to the hair matrix. Specifically, we have studied the interaction of 2,4,6-trinitrotoluene (TNT) and triacetone triperoxide (TATP) as a function of chemical pretreatment with acetonitrile, neutral and alkaline hydrogen peroxide, methanolic KOH and potassium permanganate, and the morphological changes that accompany these treatments. While differences in vapor pressure can account for quantitative differences between TNT and TATP sorption, both are markedly affected by the chemical rinses. Examination of the hair surface shows different degrees of smoothening following rinsing, suggesting that the attachment to hair is largely a surface phenomenon involving the 18-methyleicosanoic acid lipid layer. Density functional theory calculations were employed to explore possible nucleation sites of TATP microcrystals on the hair. We conclude that some of the sites on melanin granular surfaces may support nucleation of TATP microcrystals. Moreover, the calculations support the experimental finding that dark hair adsorbs explosives better than light hair.     

Physical security: An introduction

Information and Communication Technologies (ICTs) are extending the arena within which extremists and terrorists operate. Among the most active participants are Islamists and the Far Right, whose increasingly networked formats are enhanced by such technologies. These provide them with new benefits: interconnectivity; anonymity; cheapness; power enhancement; new audiences. Islamists and Jihadists are turning to the Internet to recruit, and to issue religious injunctions to the world-wide Muslim community. The stealthy growth of the U.S. militias was aided by the Internet, and white supremacists and neo-Nazis in the U.S., Europe, and elsewhere increasingly see it as the last communication medium free of interference, and which they can use to best effect. Although all use it to communicate, they are poised to use it for command and control.