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ABSTRACTFroth flotation is commonly used for the separation of rare earth minerals (REMs). A better understanding of flotation is of interest for REMs and non-sulfide minerals that carry other elements such as niobium and lithium. This study explores the effect of grinding conditions and water quality on the flotation performance of REMs at laboratory scale using material from the Ashram carbonatite deposit (Canada). Denver cell testing was used to evaluate how different particle sizes (P80between 20 and 34 µm) and rod size distributions in conventional grinding impacted the performance of REM flotation using a hydroxamic acid collector (1120 g/t). The effect of water quality (i.e. presence of rust or other species) was also evaluated. REMs, mostly monazite, represented 3% of the feed material mass with dolomite as the main gangue mineral. A P80of 24 µm strikes a compromise between sufficient liberation and limited entrainment. Grinding media corrosion negatively affected separation efficiency, causing recovery of quartz, which was possibly activated. While entrainment is responsible for over 50% of dolomite recovery, aggregation and/or slow gangue flotation account for another 40% and play an important role in achieving selectivity, highlighting the role of pulp chemistry in selective flotation of REMs.

L’incontinentia pigmenti est une dysplasie ectodermique rare liée à l’X, provoquée par des mutations du gène NEMO. Dans 80 % des cas, elle résulte d’une délétion des exons 4 à 10, classiquement létale chez le fœtus masculin. Ces dernières années, des cas de garçons viables, porteurs de mutations hypomorphes du gène NEMOont été décrits. Malgré cela, les directives en matière de conseil génétique restent limitées. Nous avons réalisé une revue systématique de la littérature afin de décrire les manifestations cliniques associées à ces mutations chez le garçon et permettre de fournir une information plus précise aux femmes présentant un phénotype clinique d’incontinentia pigmenti mais non porteuses de la délétion classique.

L’auteur propose ses propres réflexions à la lecture de l’entretien entre Catherine Malabou et Liviu Poenaru, centrées sur le thème des limites, de leur franchissement comme entreprise de déconstruction et reconstruction identitaire. Différentes problématiques « trans » abordées dans cet entretien sont commentées : exil, queer, affect, plasticité, gender studies, féminisme, interface homme–machine. La conclusion est que ce rappel utile de la contingence des limites, normes, identifications, ne signifie pas que celles-ci soient à proscrire, mais bien à être soumise à une évaluation subjective. Il ne faudrait pas faire de l’anormalité une nouvelle norme.

Le mouvement psychanalytique francophone, longtemps resté crispé au Freud de la première topique, s’est désintéressé de la physiologie à laquelle l’inventeur de la psychanalyse accordait tant d’importance comme fondement de la psychologie. La neuropsychologie anglo-saxonne a suivi la voie contraire, celle de Théodule Ribot (« La physiologie est première »), de William James (« Je vois un ours, je tremble, j’ai peur ») et de Noam Chomsky (« Une capacité de langage génétiquement déterminée spécifie une certaine classe de grammaires humainement accessible »).

Les auteurs proposent d’exposer dans un premier temps la théorie freudienne de la mémoire, dans un second temps les modèles neurophysiologiques actuels depuis les travaux de Ribot, James, Kandel, Tulving, Atkinson, Schiffrin, Baddeley, Hich, Pribram, Schore, Cornelius, Changeux, Dehaene, Solms, Panksepp … Ce parcours est l’occasion d’évoquer le rôle du système limbique, la réalité physico-chimique du fonctionnement mnésique, la neurophysiologie du refoulement, de la prise de conscience, de l’oubli, de la consolidation, de la symbolisation. Une nouvelle localisation extra-corticale des modules de la conscience est abordée. Les auteurs concluent par un hommage à Alan Turing, victime du « silence des mémoires ».

Le concept d’excitation est utilisé en physique, physiologie, psychologie et psychanalyse. L’article passe en revue l’historique de ce concept dans ces différentes disciplines scientifiques, dont la psychanalyse, considérée comme une science de la nature. Si le mouvement psychanalytique s’est pendant longtemps désintéressé de ce concept, auquel pourtant Freud, physicaliste militant, était très attaché, il s’est produit un revirement dans les années 1980. Au même moment, les sciences cognitives devenaient neurocognitives et avancent, de ce fait, dans une meilleure compréhension du freudisme. Un nouveau dialogue, après certains échecs ici relatés, est actuellement en cours pour que la psychanalyse retrouve pleinement son statut originel de science de la nature.

Les maladies auto-inflammatoires sont la conséquence de dysrégulations des réponses immunitaires innées. Nous décrivons un nouveau phénotype dont les manifestations et les conséquences fonctionnelles sont expliquées par une mutation hétérozygote dans le gène codant la Cdc42 Rho guanosine triphosphatase (GTPase).

A single-junction core-shell GaAs nanowire (NW) solar cell on Si (1 1 1) substrates is presented. A Ga-assisted vapor-liquid-solid growth mechanism was used for the formation of a patterned array of radial p-i-n GaAs NWs encapsulated in AlInP passivation. Novel device fabrication utilizing facet-dependent properties to minimize passivation layer removal for electrical contacting is demonstrated. Thorough electrical characterization and analysis of the cell is reported. The electrostatic potential distribution across the radial p-i-n junction GaAs NW is investigated by off-axis electron holography.

Les taches café-au-lait (TCL) sont un symptôme dermatologique fréquent chez l’enfant. Dans la majorité des cas, elles sont sans signification médicale. Elles sont parfois le signe précoce d’une génodermatose et font partie des critères de diagnostic de la neurofibromatose de type 1 (NF1). Il n’existe aucune recommandation ou consensus d’expert sur la prise en charge des enfants avec TCL multiples isolées. Nous avons réalisé une étude de pratiques médicales face aux TCL de l’enfant prépubère.

Les dysplasies ectodermiques (DE) sont des génodermatoses rares caractérisées par une anomalie du développement et/ou de l’homéostasie d’au moins deux structures dérivant de l’ectoderme : ongles, dents, système pileux et certaines glandes. Environ 100 DE sont répertoriées. Récemment, une mutation du gène PRKD1a été identifiée chez trois patients présentant l’association DE-cardiopathie congénitale. Au travers d’une quatrième observation, nous précisons les manifestations dermatologiques et soulignons l’importance d’explorations cardiaques morphologiques.

Boron powder was synthetized by reducing a boron halide in a microwave plasma : BCl3+ 3/2 H2[MATH]B + 3 HCl Synthetized powder is under micro sized, amorphous and contains high chlorine level. It is necessary to inflict a thermal treatment to purify and recrystallize the powder before densification. Direct hot isostatic pressing on this powder conducts to broken samples. It is realized in a vacuum furnace at temperaure between 1500 and 2000°C on 30 * 30 mm cylinders made using cold isostatic pressing at 400 MPa. Green density is among 1.3. Boron recrystallizes in [MATH] rhomboedral form. Total transformation is obtained at temperatures up to 1900°C, but density is almost the same the rough material one. No diffusion can be observed between powder grains. Hot isostatic pressing was used for the densification. Samples are put in titanium can with a carbon diffusion barrier. The pressure applied was 150 MPa and temperature varies between 1250 and 1600°C. Theoretical density is obtained at 1600°C without grain size increase. Total densification of plasma synthetized boron powder is obtained by hot isostatic pressing, but a thermal recrystallization treatment is necessary before H.I.P.

To evaluate whether the presence of leukoaraiosis or multiple lacunes is associated with symptomatic intracerebral hemorrhage (ICH) and 90-day outcome after thrombolytic treatment with tissue plasminogen activator (tPA).

Glycolipid recognition is a common motif in cellular physiology and bacterial pathogenesis. Such protein/lipid interactions are most conveniently demonstrated by the thin-layer chromatogram overlay. We have designed a simple affinity matrix for the purification of such glycolipid (or lipid) binding ligands based on the same principle, i.e., glycolipid (or lipid) adsorbed onto silica. The versatility of the procedure is demonstrated by the purification of several anti-glycolipid antibodies and anti-phosphatidyl ethanolamine (anti-PE) and the affinity purification of the Escherichia coli-derived verotoxin which binds to globotriaosyl ceramide.

The NeutRELISA, a modification of the receptor enzyme-linked immunosorbent assay developed for the detection of verocytotoxin 1 (VT1) which permits the rapid detection of neutralizing antibodies (NAb) against this toxin, has been performed. A standard concentration of VT1 was preincubated with VT-immune or nonimmune rabbit serum. The serum-toxin mixtures were then added to microtiter plates coated with deacylated globotriosyl ceramide (lyso-Gb3). The reduction of VT1 binding to lyso-Gb3 in the immune serum-toxin mixtures compared with the VT1-Gb3 binding in the nonimmune serum-toxin mixtures was detected by using mouse monoclonal antibody to VT1. After standardization of the NeutRELISA with rabbit sera, 57 human control serum samples were tested to establish a cutoff value below which NeutRELISA results would be considered positive. Thirty-three single serum samples known to demonstrate NAb to VT1 by biological assay reproducibly demonstrated VT1 NAb when tested by the NeutRELISA. There was a close correlation between the biological VT1 neutralization assay and the NeutRELISA. This assay offers a practical, rapid, and reliable approach for the detection of NAb to VT1 and other verocytotoxins.

We have measured simultaneously plasma renin activity (PRA), aldosterone and catecholamines in the plasma of 3 groups of pregnant women after the 20th week:group 1 of 16 normotensive controls, group II of 17 women with rest responding hypertension (RRH), group III of 18 women with permanent hypertension (PIH). All the patientswere ambulatory on a normal salt diet. PRA was significantly higher in the RRH than in the control and PIH groups (15, 8-2, 3ng/ml/1 versus 6, 7±0, 5 and 8, 9±0, 9 respectively). Plasma epinephrine (PE) and norepinephrine (PNE) were significantly higher in the PIH than in the control and RRH groups (jespectively 135-28 pg/ml versus 56±13 and 63±17 for PE and 387±91 versus 206±32 and 200±47 pg/ml for PNE). In the PIH group there was a negative correlation between PEA and blood uric acid. It is concluded that the adrenic system is activated in PIH whereas the renin angiotensin system is activated in RRH of pregnancy.

The various group techniques used in the treatment of neurotic children and adolescents are reviewed and discussed under three main categories corresponding to divergent theoretical views on the development of personality and the nature of psychotherapy.Slavson's group activity and Ginott's group play are defined as orthopedagogic methods meant to repair the frail ego of the child traumatized by frustrations and rejections from the environment.Moreno's psychodrama centered on role learning is based on a sociological conception of psychic growth. Catharsis through action is a common therapeutic goal pursued by all these approaches. While retaining the instrumental aids introduced by Moreno's school, Lebovici, Anzieu and Boulanger elaborated forms of group psychodrama analytically oriented and devised to foster insight through the interpretation of play.Group analysis was systematically applied to kindergarten, latency and adolescent patients by Anthony, who labelled his innovations, the ‘small table’, the ‘small room’ and the ‘small circle’ techniques. Boulanger restricts to preadolescents and adolescents verbal group analysis, and suggests group analytic psychodrama for late latency and group psychodrama for drawing and painting for early latency children. The collective fantasies of the group members are interpreted in the here and now of the transference situation.Group psychoanalysis, adapted to the medium most suited to the age of the patients, is considered by the writer as the appropriate treatment for psychoneurotic children and adolescents. Insight into inner conflicts and transference fantasies is not checked by the intrusion of the therapist in the reality of the environment or by his participation in the acting out — the handicap of family therapy or group activities and orthodox psychodrama. The limitations in conceptualization and verbalization of the young patient, his inferior and dependent status with regard to the adult therapist are more readily overcome in a group of peers than in individual psychotherapeutic encounters. The influence of the process of socialization during these formative years on all aspects of personality development is also greatly enhanced by group psychotherapy.