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A variety of tool shoulder designs comprising three families i.e. blade, spiral and circular shaped scrolls, were produced to improve the material flow and restrictions to avoid the tunnel void. The bobbin tools were manufactured by 3D printing additive manufacturing technology using solid filament. The butt weld joint was produced by each tool using plasticine as the workpiece material. The apparent surface features and bi-colour cross-sections provided a physical flow comparison among the shoulder designs. For the bobbin friction stir welding (BFSW), the tool shoulder with a three-spiral design produced the most stability with the best combination of the flow patterns on surface and cross-sections. The circular family tools showed a suitable intermixing on the surface pattern, while the blade scrolls showed better flow features within the cross-sections. The flow-driven effect of the shoulder features of the bobbin-tool design (inscribed grooves) was replicated by the 3D-printed tools and the analogue modelling of the weld samples. Similar flow patterns were achieved by dissimilar aluminium-copper weld, validating the accuracy of the analogue plasticine for the flow visualization of the bobbin friction stir welding.

Electron Backscatter Diffraction (EBSD) was used to determine microstructural evolution in AA6082-T6 welds processed by the Bobbin Friction Stir Welding (BFSW). This revealed details of grain-boundaries in different regions of the weld microstructure. Different polycrystalline transformations were observed through the weld texture. The Stirring Zone (SZ) underwent severe grain fragmentation and a uniform Dynamic Recrystallisation (DRX). The transition region experienced stored strain which changed the grain size and morphology via sub-grain-boundary transformations. Other observations were of micro-cracks, the presence of oxidization, and the presence of strain hardening associated with precipitates. Flow-arms in welds are caused by DRX processes including shear, and low and high angle grain boundaries. Welding variables affect internal flow which affects microstructural integrity. The shear deformation induced by the pin causes a non-uniform thermal and strain gradient across the weld region, leading to formation of mixed state transformation of grain morphologies through the polycrystalline structure. The grain boundary mapping represents the differences in DRX mechanism I different regions of the weld, elucidates by the consequences of the thermomechanical nature of the weld. The EBSD micrographs indicated that the localised stored strain at the boundary regions of the weld (e.g. flow-arms) has a more distinct effect in emergence of thermomechanical nonuniformities within the DRX microstructure.

The purpose of this study is to elucidate the flow features of the dissimilar Al-Cu welded plates. The welding method used is Bobbin Friction Stir Welding (BFSW), and the joint is between two dissimilar materials, aluminium alloy (AA6082-T6) and pure copper. Weld samples were cut from along the weld line, and the cross-sections were polished and observed under an optical microscope (OM). Particular regions of interest were examined under a scanning electron microscope (SEM) and analysed with Energy Dispersive X-ray Spectroscopy (EDS) using the AZtec software from Oxford Instruments. The results and images attained were compared to other similar studies. The reason for fracture was mainly attributed to the welding parameters used; a higher rotational speed may be required to achieve a successful BFSW between these two materials. The impact of welding parameters on the Al-Cu flow bonding and evolution of the intermetallic compounds were identified by studying the interfacial microstructure at the location of the tool action. The work makes an original contribution to identifying the solid-phase hybrid bonding in Al-Cu joints to improve the understanding of the flow behaviours during the BFSW welding process. The microstructural evolution of the dissimilar weld has made it possible to develop a physical model proposed for the flow failure mechanism.

The flow-inducing effect of the bobbin-tool features (tri-flat pin and scrolled shoulder) were replicated by a simple analogue model for aluminium welds by layered plasticine samples. Flow patterns of the weld zone were clarified by a typical stereomicroscopy instrument assisted by dark-field/bright-field illumination. The effects of the pin features, specifically threads and flats in centre of bond zone and scrolled shoulder in sides of stirred zone, were identified. This study shows that internal flow features for BFSW welds is transferable from the friction stir welding process to the functional metal forming processes such where the shearing can extensively affect the microstructure. The similarity between the flow pattern of the provided aluminium samples and the plasticine analogue can validate the accuracy of the flow model presented in this work.

La clozapine est un neuroleptique qui a un rôle important dans la prise en charge de la schizophrénie et des psychoses réfractaires. Puisqu’elle induit des neutropénies sévères, l’Agence nationale de sécurité du médicament (ANSM) a créé un cahier de surveillance à renseigner pour tous les patients concernés.

Statistical process control (SPC) theory takes a negative view of adjustment of process settings, which is termed tampering. In contrast, quality and lean programmes actively encourage operators to acts of intervention and personal agency in the improvement of production outcomes. This creates a conflict that requires operator judgement: How does one differentiate between unnecessary tampering and needful intervention? Also, difficult is that operators apply tacit knowledge to such judgements. There is a need to determine where in a given production process the operators are applying tacit knowledge, and whether this is hindering or aiding quality outcomes. The work involved the conjoint application of systems engineering, statistics, and knowledge management principles, in the context of a case study. Systems engineering was used to create a functional model of a real plant. Actual plant data were analysed with the statistical methods of ANOVA, feature selection, and link analysis. This identified the variables to which the output quality was most sensitive. These key variables were mapped back to the functional model. Fieldwork was then directed to those areas to prospect for operator judgement activities. A natural conversational approach was used to determine where and how operators were applying judgement. This contrasts to the interrogative approach of conventional knowledge management. Data are presented for a case study of a meat rendering plant. The results identify specific areas where operators’ tacit knowledge and mental model contribute to quality outcomes and untangles the motivations behind their agency. Also evident is how novice and expert operators apply their knowledge differently. Novices were focussed on meeting throughput objectives, and their incomplete understanding of the plant characteristics led them to inadvertently sacrifice quality in the pursuit of productivity in certain situations. Operators’ responses to the plant are affected by their individual mental models of the plant, which differ between operators and have variable validity. Their behaviour is also affected by differing interpretations of how their personal agency should be applied to the achievement of production objectives. The methodology developed here is an integration of systems engineering, statistical analysis, and knowledge management. It shows how to determine where in a given production process the operator intervention is occurring, how it affects quality outcomes, and what tacit knowledge operators are using. It thereby assists the continuous quality improvement processes in a different way to SPC. A second contribution is the provision of a novel methodology for knowledge management, one that circumvents the usual codification barriers to knowledge management.

L’éthylisme chronique entraîne des problèmes psychocomportementaux et des déficits cognitifs qu’il est nécessaire de traiter conjointement. Les troubles intellectuels des personnes alcoolo-dépendantes vont compliquer et ralentir le travail thérapeutique. Une prise en charge intégrant un programme de réhabilitation cognitive n’est pas toujours facile à mettre en place et à suivre chez ce type de patient. Les résultats fonctionnels directs sont souvent difficiles à anticiper. En revanche, les conséquences d’une telle approche sont multiples et les interactions entre les composantes psychoaffectives, comportementales et cognitives nombreuses. Le cas clinique décrit permet d’illustrer l’influence d’un travail neuropsychologique sur la prise en charge globale. Les outils utilisés pour les évaluations ainsi que pour la rééducation peuvent secondairement permettre un travail sur la métacognition. Ainsi, les performances obtenues aux tests effectués, le temps nécessaire à la réduction des pertes intellectuelles et les restaurations fonctionnelles réalisées facilitent la prise de conscience des troubles et donc des conséquences neurobiologiques sur le cerveau d’une prise excessive d’alcool. Cette influence indirecte des interventions sur les déficits cognitifs peut réduire les fluctuations motivationnelles de ces patients et constituer une aide à l’abstinence. Il est important de considérer l’ensemble de ces effets dans les propositions thérapeutiques afin d’optimiser les chances de résultats.

En cas d’événement NRBC, le port d’un équipement de protection engendre des contraintes modifiant les capacités opérationnelles de son utilisateur. D’emblée, le port d’une tenue de protection entraîne une réduction des capacités sensorielles (vision, audition, dextérité) ainsi qu’une augmentation de la charge respiratoire en fonction des caractéristiques du système utilisé (appareil respiratoire filtrant ou isolant, masque FFP3). Puis, selon la durée du port de la tenue, la principale contrainte est d’ordre thermophysiologique, car les tenues de type 1, 2 ou 3 entravent les échanges thermiques, exposant l’intervenant à des risques médicaux pouvant engager le pronostic vital (coup de chaleur, déshydratation). Pour prévenir ces risques, il est nécessaire de connaître les conditions d’emploi de ces équipements, en particulier leur durée limite d’utilisation afin de ne pas dépasser les seuils de tolérance physiologique. Enfin, l’entraînement régulier au port des tenues NRBC doit permettre aux personnels de secours de s’acclimater à exercer leurs compétences dans un environnement contaminé, afin de fournir des capacités opérationnelles optimales.

Homocamptothecin (hCPT), a camptothecin (CPT) analogue with a seven membered β-hydroxylactone which combines enhanced plasma stability and potent topoisomerase I (Topo I)-mediated activity, is an attractive template for the elaboration of new anticancer agents. Like CPT, hCPT carries an asymmetric tertiary alcohol and displays stereoselective inhibition of Topo I. The preparation and biological screening of racemic hCPT analogues are described. The 10 hCPTs tested were better Topo I inhibitors than CPT. Fluorinated hCPTs 23c,d,f,g were found to have potent cytotoxic activity on A427 and PC-3 tumor cell lines. Their cytotoxicity remained high on the K562adr and MCF7mdr cell lines, which overexpress a functionally active P-glycoprotein. Fluorinated hCPTs were more efficacious in vivo than CPT on HT-29 xenografts. In this model, a tumor growth delay of 25 days was reached with hCPT 23g at a daily dose of 0.32 mg/kg, compared to 4 days with CPT at 0.625 mg/kg. Thus difluorinated hCPT 23g warrants further investigation as a novel Topo I inhibitor with high cytotoxicity toward tumor cells and promising in vivo efficacy.

A simple dynamic model accounting for atomic interactions between nearest neighbors is presented and demonstrated to predict correctly the anisotropy for production of defects in n-GaAs by electron irradiation. A hard core potential is used to describe the atomic interactions. A reasonable agreement between the model and the experimental results is obtained if As displacements are assumed to be responsible for the observed defects, with a hard core radius equal to about 1 Å and an isotropic threshold energy for displacement equal to 9 eV. The anisotropy for production of hole traps in p-GaAs has been experimentally studied. The main hole traps are shown to exhibit exactly the same anisotropy as the electron traps in n-GaAs, and are concluded to originate also in As displacements.

Bulk Czochralski and VPE layers of n-GaAs have been irradiated with 1 MeV electrons at about 300°C, temperature at which primary defects are not stable. Up to seven electron traps are thus observed to be introduced. The dominant trap (I1) has an activation energy and a capture cross section very close to the so-called EL2 center, which suggests that EL2 could be introduced by a high temperature electron irradiation. The introduction rate of I1 is about 1cm-1, that is the same order of magnitude as those of the traps (E-traps) introduced by a room temperature irradiation, and two orders of magnitude larger than those of the traps observed after the annealing (200–300°C) of the E-traps. With a starting dopant concentration of 2×1016cm-3, we have obtained a quite complete compensation of free carriers after a total fluence of 1017e/cm2.

Abstract: The paper describes a device (Paracycle), that uses functional neuromuscular stimulation to exercise subjects, explore FNS technology and provide paraplegics with locomotion. The Paracycle is a four-wheeled cycling vehicle that may be used as a stationary exercise device or for locomotion. It incorporates a fully adjustable seat and an electric motor to assist or retard the cycling motion, as well as speed and direction controls. Furthermore, it has braces to fasten the feet to the pedals and to stabilise the ankle, as well as gearing to enable subjects with very small forces to move the vehicle forward. Results are presented for two cases studies. Good stability of the leg was achieved during the cycling motion and this would appear to be a major advantage of functional neuromuscular stimulation cycling over functional neuromuscular stimulation gait. Important areas for future research include a better understanding of the biomechanics of functional neuromuscular stimulation cycling and the development of Paracycle-like devices that can be used independently by paraplegics.

Ruthenium complexes catalyze the oxidation of alcohols to the corresponding ketones or aldehydes when Ca(OCl)2 or NaIO4 are used as oxygen donors in the presence of water (5-10 equiv.). The reactions take place at room temperature affording products in yields of 45-80%.

Abstract: Percutaneous coronary intervention (PCI) has become an effective therapy to treat coronary artery diseases. However, one of the major drawbacks of PCI is the occurrence of restenosis in 8 to 40% of all treated patients. The GENetic Determinants of Restenosis (GENDER) project was designed to study the association between genetic polymorphisims and clinical restenosis. The discovery of genetic variants associated to the occurrence of restenosis after PCI may provide a more tailored therapy and may serve as rationale for new antirestenotic therapies. So far, several candidate gene approaches had already been performed in the GENDER samples but a Genome Wide Association Scan (GWAS) was still lacking. Here, we present preliminary results from the GWAS we are currently carrying out in the GENDER population. (Neth Heart J 2009;17:262–4.)

Abstract: In the past decade, research into cardiovascular diseases, such as atherosclerosis and restenosis, has been focused on the identification of genetic factors that determine disease risk besides clinical risk factors. Many genes in lipid metabolism, vascular homeostasis, haemostasis and inflammation have been found to be related to coronary artery disease1 and the multifactorial nature of the disease suggests a role for many other, yet uninvestigated genes. Previous research from our department has demonstrated the importance of genetics in restenosis after a percutaneous coronary intervention (PCI). Polymorphisms in several inflammatory genes, such as TNFα, eotaxin, CD14, GM-CSF, IL-10, caspase-1, but also noninflammatory genes, such as LPL, stromelysin-1 and the β adrenergic receptor have been found to be associated with the risk of restenosis.2-5 It has become clear, however, that part of the gene-environmental interactions relevant for complex diseases is regulated by epigenetic mechanisms such as histone acetylation and DNA methylation.

We report on the transconductance dependence on gate length for pseudomorphic (PM) and conventional GaAs gate SISFETs. With an identical material structure, except for the GaInAs channel, PM-SISFETs have higher transconductances at room temperature, for gate lengths between 1 µm and 19 µm. At 77 K, however we show that higher transconductances are obtained with conventional SISFETs having gate lengths larger than 2 µm.

The primary or secondary alcohols (I) are treated with calcium hypochlorite in the presence of ruthenium trichloride and water to form the corresponding carbonyl compounds (IIa) ‐ (IIc) and (IIe).

It is now well known that PSA assays measure simultaneously free PSA (FPSA) and PSA bound to α-1 antichymotrypsin (PSA-ACT). Furthermore specific measurement of the free form gives additional information on PSA in the distinction between benign prostate hypertrophies (BPH) and prostate cancer.In order to evaluate the contribution of free PSA in addition to that of total PSA, we tested 105 patients’ serum with prostate pathology (prostate cancer or BPH). All patients had a digital rectal examination, a total PSA measurement (values between 2 and 30ng/ml) and possibly a biopsy as well.Results obtained showed that with the total PSA (cut-off 4ng/ml), the measurement does not allow a good discrimination between BPH and prostate cancer (specificity of 46%). For this population (105 patients) the positive predictive value (PPV) of total PSA was only 48%.The use of free PSA measurement and the ratio of free PSA to total PSA (F/T PSA) allowed the PPV to rise to 87%.These first results showed that for the patient population which had given low specificity for a simple total PSA measurement (4 to 14ng/ml), the ratio F/T PSA allowed the detection of 60% prostate cancer with a specificity of 95%.