Comment on "Typicality for Generalized Microcanonical Ensemble"

The validity of the so-called "typicality" argument for a generalised microcanonical ensemble proposed recently is examined.Comment: Version to appear in PR

Les effets pléiotropes d’un inhibiteur réversible de récepteurs P2Y12

RésuméLe cangrelor actif par voie injectable a été le premier inhibiteur réversible des récepteurs P2Y12, et maintenant, le ticagrelor, premier inhibiteur réversible actif par voie orale, ouvre une ère nouvelle dans l’inhibition de la voie de l’ADP: en effet, ils n’ont ni la même pharmacocinétique ni la même pharmacodynamie que les inhibiteurs irréversibles que sont les métabolites actifs des thiénopyridines auxquels nous étions accoutumés. La molécule agit par sa concentration plasmatique et non par son affinité pour son récepteur. L’activité de la molécule va donc pouvoir se porter:-sur des sites P2Y12 extra-plaquettaires qui n’étaient que peu ou pas accessibles aux inhibiteurs irréversibles, et ainsi dévoiler au niveau vasculaire des effets vasodilatateurs;-sur des sites récepteurs transporteurs de moindre affinité. C’est ainsi que le ticagrélor inhibe l’« erythrocyte equilibrative nucleoside transporter », transporteur situé à la membrane des globules rouges et responsable de l’incorporation rapide et active de l’adénosine dans les globules. L’inhibition de l’ENT induit une accumulation d’adénosine avec toute une série d’effets possibles, « les effets adénosine », qui peuvent potentiellement renforcer l’effet primaire: l’adénosine a une activité directe d’anti-agrégant plaquettaire et pas seulement inhibitrice de l’agrégation plaquettaire; l’adénosine a des effets vasculaires: vasodilatateurs mais aussi de pré- et de post-conditionnement en protection contre l’ischémie-reperfusion, et des effets anti-inflammatoires au niveau local. Mais c’est aussi cet effet adénosine qui peut expliquer certains effets secondaires notés lors des études avec le ticagrélor (dyspnée, augmentation des taux plasmatiques d’acide urique et de créatinine, bradycardie en particulier). L’observation que ces patients présentant ces effets secondaires tirent un bénéfice même supérieur du traitement est un argument fort pour indiquer que l’effet adénosine participe de manière significative au bénéfice global net du traitement par le ticagrélor.SummaryCangrelor, administered intravenously, was the first reversible inhibitor of P2Y12 receptors. More recently, ticagrelor is the first oral reversible inhibitor of P2Y12 receptors. These drugs act through their extracellular concentration, in contrast to thienopyridines, which act through irreversible binding of their active metabolite to P2Y12 receptors. These drugs also differ in terms of their pharmacokinetics, pharmacodynamics and modes of action (direct vs indirect). Besides inhibition of platelet P2Y12 receptors, ticagrelor also acts on P2Y12 receptors of other cells. These receptors are much less accessible to the high affinity and short plasma survival of the active metabolites of thienopyridines. At the vascular level, inhibition of P2Y12 receptors on smooth muscle cells prevents vasoconstriction induced by adenosine diphosphate. Ticagrelor also inhibits the erythrocyte equilibrative nucleoside transporter (ENT) (which is responsible for the rapid and active incorporation of adenosine into erythrocytes), and therefore leads to extra-cellular adenosine accumulation. Adenosine, a potent cellular mediator responsible for the ‘adenosine effects’of ticagrelor, can reinforce the primary effect of ticagrelor (adenosine has a direct inhibitory effect on platelet activation/aggregation and is not only an inhibitor of the ADP pathway of platelet activation/aggregation). Adenosine exerts multiple vascular effects – vasodilatation and protection against ischaemic – reperfusion lesions (pre-conditioning and post-conditioning effects) – and these effects can explain some of the secondary effects observed during clinical studies in patients receiving ticagrelor (dyspnoea, increase in plasma concentrations of uric acid and creatinine, bradycardia). The observation that patients affected by such side-effects benefit to a greater extent than patients who do not, provides substance to the argument that the adenosine effect of ticagrelor is significantly implicated in the net global benefit of treatment in patients with acute coronary syndromes

Can dissuasive cigarettes influence young peoples’ perceptions of smoking?

Background In order to counter the attractiveness of cigarettes, Article 11 of the Framework Convention on Tobacco Control mentions the possibility of including a health warning on cigarettes. The objective of this study was toexplore perceptions of cigarettes designed to be dissuasive (either displaying a text health warning or pictogram, unattractively coloured, or a combination of these). Methods In-depth interviews were conducted with 31 people in France aged 15-25 years (11daily smokers, 10 occasional smokers, 10 non-smokers, 15 females, 16 males). Participants were shown the different dissuasive cigarettes (displaying the warning \u27Smoking kills\u27, a ‘skull and crossbones’ pictogram, unattractive shades of brown or green, or a combination of all three). Open-ended questions were asked about the attractiveness of the cigarettes, perception of risk, the image of the smoker, and influence on desire to quit or not to start. Discussions were audio-recorded and transcribed. Manual coding and « IRaMuTeQ » software was used to analyse the data. Results The different dissuasive elements used were found to increase negative health perceptions (e.g.  increase risk), reduce positive smoker image and the perceived pleasure of smoking (e.g. embarrassment of smoking in front of friends), decrease desire to start smoking and increase desire to quit. The most dissuasive cigarette was an unattractively coloured cigarette which displayed both the warning \u27smoking kills\u27 and \u27skull and bones\u27 pictogram. Conclusion This study highlights the importance of the appearance of the cigarette, and suggests that dissuasive cigarettes may be an innovative tobacco control measure for governments

A Non-Intrusive GMA Welding Process Quality Monitoring System Using Acoustic Sensing

Most of the inspection methods used for detection and localization of welding disturbances are based on the evaluation of some direct measurements of welding parameters. This direct measurement requires an insertion of sensors during the welding process which could somehow alter the behavior of the metallic transference. An inspection method that evaluates the GMA welding process evolution using a non-intrusive process sensing would allow not only the identification of disturbances during welding runs and thus reduce inspection time, but would also reduce the interference on the process caused by the direct sensing. In this paper a nonintrusive method for weld disturbance detection and localization for weld quality evaluation is demonstrated. The system is based on the acoustic sensing of the welding electrical arc. During repetitive tests in welds without disturbances, the stability acoustic parameters were calculated and used as comparison references for the detection and location of disturbances during the weld runs

CO oxidation over nonstoichiometric nickel manganite spinels

Nonstoichiometric nickel–manganese spinel oxides, NixMn3−x ▭3δ/4O4+δ (1≥x≥0), have been synthesized by calcination in air of mixed oxalates at 623 K. These materials are shown to be highly reactive for CO oxidation, some conversion being observed at room temperature for the most active solid (x=1.0). The interaction of CO and O2 with these oxides has been studied by in situ IR spectroscopy under steady-state and transient reaction conditions. A detailed mechanism is proposed wherein CO reacts with coordinatively unsaturated cations to give carbonyl complexes which in turn react with surface oxygen activated on anionic vacancies. Adsorbed and gaseous CO2 also undergo much slower side reactions with lattice oxygen or surface hydroxide groups to give more stable hydrogen carbonate and carbonates species, which lead to catalyst deactivation. Marked effects of pretreatment are explained on the basis of the observed kinetics and the proposed mechanis

Integrated heterodyne array receivers for submillimeter astronomy

The advent of large format (~100 pixel) spectroscopic imaging cameras at submillimeter wavelengths would fundamentally change the way in which astronomy is performed in this important wavelength regime. While the possibility of such instruments has been discussed for more than two decades, only recently have advances in mixer technology, device fabrication, micromachining, digital signal processing, and telescope design made the construction of such an instrument possible and economical. In our paper, we will present the design concept for a 10×10 heterodyne camera

Synthesis, thermogravimetric and high temperature X-ray diffraction analyses of zinc-substituted nickel manganites

Stoichiometric spinel phases Mn2.352xNi0.65ZnxO4 were prepared by thermal decomposition of mixed oxalate precursor powders Mn0.782aNi0.22ZnaC2O4znH2O (with 0 # a # 0.53) at 900°C. Cation-deficient phases Mn2.352xNi0.65Znxh3d/4O41d were identified in the temperature range 350–500°C. The nonstoichiometric coefficient d was found to strongly depend on the zinc content and the decomposition temperature. We showed that the introduction of zinc into the spinel phase enlarges the stability domain of the structure and inhibits oxidation at least up to 900°C. A cubic single-phase was observed for x # 1.00. The lattice parameter variation of the oxides in the composition range 0 # x # 0.60 can be explained using Poix’s method, in terms of the distribution of Zn21 cations on the tetrahedral sites. However, for higher zinc content (x . 0.6) a detailed analysis of data showed that a small fraction of Zn21 is located on octahedral sites

Neuropathic complications after 157 procedures of continuous popliteal nerve block for hallux valgus surgery. A retrospective study

SummaryBackgroundContinuous peripheral nerve block (CPNB), in particular at the popliteal fossa, is widely used in orthopedic surgery, allowing good postoperative analgesia. Possible neuropathic complications, however, remain poorly known.ObjectiveTo review the characteristics of peripheral neuropathy (PN) after sciatic CPNB at the popliteal fossa, estimating prevalence, severity, evolution and possible risk factors, especially those relating to the procedure.MethodsRetrospective study of PN associated with popliteal fossa CPNB for hallux valgus surgery, between November 1st, 2005 and November 1st, 2009. All procedures were analyzed (type of anesthesia, approach, nerve location technique, number of procedures by operator) with, for each case of PN, analysis of clinical and electromyographic data.ResultsOne hundred and fifty seven sciatic CPNBs were performed (92% women; mean age, 55 years). The approach was lateral (n=62), posterior (n=74) or unknown (n=21). Ultrasound guidance was combined to neurostimulation for 69 patients (44%). Three women (prevalence=1.91%), aged 19, 24 and 65 years respectively, developed associated common superficial peroneal and sural nerve injury (2), axonal on electromyography, with motor (n=1) and/or sensory (n=3) residual dysfunction.DiscussionThe higher prevalence found in the present study than in the literature (0 to 0.5%) raises questions of methodological bias or technical problems. The common peroneal and sural nerves seem to be exposed, unlike the tibial. Several mechanisms can be suggested: anesthetic neurotoxicity, direct mechanical lesion, or tourniquet-related ischemia and conduction block. Further studies are necessary to determine the ideal anesthetic procedure.ConclusionPatients should be informed of the potential risk, however rare, even during mild surgery. The best possible technique should be implemented, with reinforced surveillance.Level of evidenceLevel IV retrospective study

Peut-on influencer la représentation du tabagisme et l’envie de fumer chez les jeunes en modifiant le design des cigarettes

The objective of this research is to study the role of deterrent cigarettes (deterrence activated via colour, a warning label and a pictogram) on perceptions and smoking behaviour among youth people (15-25 years). The results show that different elements (green or brown colours, degree of covering, a warning, a « skull and cross bones » pictogram) impact the negative representations raised by the tobacco product (dangers), affect the image of smokers, reduce the pleasure to smoke and smoking behavioural intentions