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Resume A l’heure d’une medecine hyper-connectee qui pourrait nous couper de la clinique et du soin, et du principe de precaution toujours mis en exergue signe d’une insecurite croissante, la confiance est mise a l’epreuve. A partir d’une etude sur le toucher dans le soin menee en 2016 aupres de medecins, infirmier(e)s, maieuticien(e)s, kinesitherapeutes, aide-soignant(e)s, nous avons souhaite approfondir la reflexion sur la qualite de la relation de soin entre le professionnel de sante et ses patients. Une relation de soin qualifiee de « bonne » passe inexorablement par la maitrise du Toucher d’autant que sa vitale moderation va dans le sens de plus de democratie sanitaire et d’autonomie de l’individu. L’adhesion du grand public a une e-medecine ne pourra se faire que si le professionnel sait « toucher » ses patients et developpe ses qualites humaines.

International audience; The impact of a relaxed InGaN pseudosubstrate on indium incorporation in a full InGaN heterostructure was investigated. Three types of InGaN pseudosubstrates were tested with different a lattice parameters ranging from 3.190 to 3.205 angstrom, that is to say, greater than that of a GaN template on sapphire. Samples were loaded together in the growth chamber in order to apply exactly the same growth conditions. The effect of the photoluminescence (PL) emission redshift was observed on InyGa1-yN buffer layers and also on InxGa1-xN/InyGa1-yN multiple quantum wells (MQWs). It was found that these pseudosubstrates have the ability to improve the indium incorporation rate, with an increasing effect as the a lattice parameter increases. A strong PL emission redshift was observed in InxGa1-xN/InyGa1-yN MQWs as a function of the increasing a lattice parameter of the InGaN pseudosubstrate, compared to a reference grown on a GaN template. It has been shown that green and amber emissions can be easily reached. A redshift of up to 42 nm was detected between various InGaN pseudosubstrate samples and up to 62 nm compared to a conventional structure emerged from a GaN buffer on the sapphire substrate. The average QW width less than 3 nm indicates a higher In content. The reduced compressive strain originating from the relaxed InGaN substrate allows the reduction in the compositional pulling effect and consequently enables an enhanced In incorporation rate.

Les reunions de concertation pluridisciplinaires (RCP) soins de support-soins palliatifs s’integrent aux RCP de specialite d’organe du 3C du CHU de Grenoble. C’est en partie a travers elles que la coordination des soins de support definie par la circulaire du 22 fevrier 2005 relative a l’organisation des soins en cancerologie est actee et mise en place autour des patients. Elles permettent l’apport de competences de recours et leur coordination. L’experience presentee souligne la diversite des questions abordees (douleurs rebelles, souffrance psychologique, prise en charge sociale, projet therapeutique…) ainsi que les aspects organisationnels de ces RCP avec les modalites de selection des patients, la tracabilite de l’activite, les modalites de suivi des avis. La forte participation medicale et paramedicale rappelle le role formateur de ces RCP aupres des professionnels, mais aussi leur fonction de soutien et de regulation par la parole echangee et la reprise des projets therapeutiques.

Resume La dialyse, sa notion implicite de sursis et ses contraintes invitent particulierement au questionnement concernant l’arret de ce traitement. En France, la loi du 22 avril 2005 relative aux droits des malades et a la fin de vie definit un cadre a l’arret de traitement, en l’autorisant sous certaines conditions, afin d’eviter une obstination deraisonnable. Peu avant la parution de cette loi, un travail de these a ete mene au CHU de Grenoble, sous la direction de l’unite de recherche et de soutien en soins palliatifs et de l’unite d’hemodialyse afin d’analyser les circonstances dans lesquelles sont discutes et decides les arrets de dialyse. Ce travail a favorise la constitution d’un groupe thematique pluridisciplinaire sur l’arret de dialyse au sein de l’Espace Ethique du CHU de Grenoble. Des situations cliniques difficiles d’arret de dialyse y ont ete analysees de facon collegiale. Les arguments necessaires a la discussion et les differentes etapes du cheminement de la reflexion a mener ont ete ainsi reperes et mis en forme pour constituer un outil d’aide a la reflexion. Cet outil souligne l’importance de la dimension temporelle, de la concertation collegiale et de l’information en vue d’une decision eclairee prise en finalite par le nephrologue referent. Sa conception initiale a ete affinee au fil de son application. Outil d’aide a la discussion, il sert de plan de reflexion pour une demarche decisionnelle cherchant a recueillir le maximum d’elements interferant sur la situation. L’analyse de ses apports mais aussi de ses insuffisances dynamise l’evolution de cet outil et le fonctionnement du groupe thematique.

We present the results of a parametric study of the interaction of intense laser pulse of intensity varying from 10 18 W/cm 2 up to 10 21 W/cm 2 with plasmas of density ranging from 10 times up to 160 times critical density. This study has been performed with the help of large 2D and 3D PIC simulations. It gives clear evidences that the divergence of the beam is an intrinsic property of the interaction of a laser pulse with a sharp density gradient. This divergence is related to the excitation of large static magnetic fields in the layer of interaction. The effective spread is a complex balance between the intensity of the beam and the plasma density.

Resume But de l'etude. – Evaluation d'une strategie pluridisciplinaire et validation d'un protocole medicochirurgical de traitement de l'occlusion intestinale maligne. Patients et methode. – Tous les patients inclus presentaient une occlusion intestinale avec carcinose peritoneale et aucun ne pouvait beneficier d'un traitement curatif. Soixante-quinze patients ont ete traites pour 80 episodes occlusifs. Le protocole comportait trois etapes therapeutiques successives. Association de steroide, d'antiemetiques, d'antisecretoires anticholinergiques et d'antalgiques pendant cinq jours (Etape I). En cas de persistance de l'occlusion arret de la corticotherapie et des antisecretoires et traitement par un analogue de la somatostatine pendant trois jours (Etape II). Si ce traitement demeurait inefficace, realisation d'une gastrostomie de decharge (Etape III). Resultats. – La mediane de duree de vie des patients etait de 31 jours. Pour les 80 episodes occlusifs consideres, l'occlusion a ete levee ou les symptomes controles par le traitement medicamenteux (Etape I) dans 50 cas (63 %), par la somatostatine (Etape II) dans 11 cas (14 %) et par la gastrostomie (Etape III) dans dix cas (13 %). Un patient a eu une endoprothese duodenale. Au total un controle des symptomes sans port de SNG au long cours dans 71 situations sur 80 (90 % cas). Cinquante-huit episodes occlusifs ont ete controles dans un delai inferieur ou egal a dix jours (72 % des cas). La mediane de delai de realisation de gastrostomie etait de 17 jours. Huit patients garderent la SNG jusqu'a leur deces. Conclusion. – Cette approche multidisciplinaire a finalement permis le soulagement des symptomes occlusifs pour 90 % des patients de l'etude, et l'existence d'un protocole medicochirurgical a facilite pour les equipes soignantes la prise en charge toujours delicate des patients en fin de vie. L'amelioration de ces resultats passe par la diminution du delai de soulagement, qui a ete superieur a dix jours dans pres d'un tiers des cas : un protocole simplifie ne comportant que deux etapes au lieu de trois est en cours d'elaboration.

Stationary plasma thrusters are devices that use crossed electric and magnetic fields to accelerate ions to high velocities. Ions are created by collisional ionization of a propellant gas with electrons injected from a hollow cathode external to the thruster. A major issue is the electron transport through the magnetic field. It is known to exceed considerably the values predicted by the classical theory. Various 2D models have shown that wall collisions, which have often been invoked as the origin of this anomalous transport, are in fact insufficient. Anomalous turbulent transport has to be added to the model to recover an adequate conductivity. In the present paper the first 2D kinetic model that shows that, indeed, plasma turbulence can explain the observed conductivity is presented. Without any free parameter the model is able to reproduce numerous experimental features. At the end of the paper a preliminary theoretical analysis of the observed instability is provided.

Resume Propos. – L’arrivee en France de nouveaux opiaces forts et de nouvelles formes galeniques pour des opiaces deja commercialises necessite une remise a jour des connaissances des praticiens. Le present travail a pour objectif d’aider le prescripteur dans le choix d’un opiace fort, de sa voie d’administration et de sa forme galenique afin d’optimiser le traitement de la douleur. Actualites et points forts. – Rappel pharmacologique des opiaces (mecanisme d’action, pharmacocinetique et pharmacovigilance). Rappel et apports sur les indications, les modalites de prescription et d’utilisation des principaux opioides forts dans les douleurs et principalement celles d’origine cancereuse. Exemples de situations avec calcul des doses necessaires de l’opiace considere a un moment donne, et pour une voie d’administration choisie. Rappels et apports sur les traitements des effets indesirables des opiaces et conduite a tenir en cas de surdosage. Perspectives et projets. – La morphine par voie orale est le traitement de reference des douleurs de nociception non suffisamment soulagees par les antalgiques du palier 1 ou 2 de l’Organisation mondiale de la sante. Ses nouvelles formes galeniques, comprimes et gel a liberation immediate, permettent la titration orale de la morphine et le traitement des acces douloureux chez les patients deja soulages par un opioide fort. Le fentanyl par voie transmuqueuse – prochainement disponible en France – est indique dans le traitement des acces douloureux chez les patients deja sous opiaces forts. Il est interessant pour sa reponse antalgique rapide, des la cinquieme minute apres l’application, et sa duree d’action courte. Le fentanyl par voie transdermique est indique pour les douleurs cancereuses stables. Il est particulierement interessant en cas d’impossibilite d’administration orale ou parenterale de la morphine et chez le patient a constipation severe sous morphine malgre la prise de laxatifs. L’hydromorphone est en France le premier opioide recommande dans les douleurs intenses d’origine cancereuse en cas de resistance ou d’intolerance a la morphine (rotation d’opiaces). Les nouveaux opioides forts et les nouvelles formes galeniques disponibles en France offrent une grande variete de possibilites therapeutiques. Leur utilisation est bien codifiee pour la douleur cancereuse et doit faire encore l’objet d’essais cliniques pour la douleur chronique non maligne.

The dispersion relation for electronic parametric instabilities of a circularly polarized laser wave is solved in the case where the distribution function is supposed to be cold in the transverse direction and to be a linear combination of a cold distribution function and of a Maxwellian in momentum in the longitudinal direction. Only densities below the critical density are considered. It is shown that the longitudinal temperature as expected reduces the growth rate, but that the existence of a hot tail is not sufficient to significantly reduce the instability. It is the bulk of the distribution function that must be heated to efficiently stabilize the system. Another important effect of the heating is to reduce the backscattered component of the instability. An example of a one-dimensional particle simulation performed in the exact conditions of validity of the theory is discussed.

Of vital importance for Inertial Confinement Fusion (ICF) are the understanding and control of the nonlinear processes which can occur during the propagation of the laser pulses through the underdense plasma surrounding the fusion capsule. The control of parametric instabilities has been studied experimentally, using the LULI six-beam laser facility, and also theoretically and numerically. New results based on the direct observation of plasma waves with Thomson scattering of a short wavelength probe beam have revealed the occurence of the Langmuir decay instability. This secondary instability may play an imporant role in the saturation of stimulated Raman scattering. Another mechanism for reducing the growth of the scattering instabilities is the so-called `plasma-induced incoherence'. Namely, recent theoretical studies have shown that the propagation of laser beams through the underdense plasma can increase their spatial and temporal incoherence. This plasma-induced beam smoothing can reduce the levels of parametric instabilities. One signature of this process is a large increase of the spectral width of the laser light after propagation through the plasma. Comparison of the experimental results with numerical simulations shows an excellent agreement between the observed and calculated time-resolved spectra of the transmitted laser light at various laser intensities.

This multicentre, randomized double-blind study was undertaken to assess the efficacy of corticosteroids as a palliative treatment of intestinal obstruction due to advanced and incurable cancer. Thirty-one French palliative care units agreed to participate in the study and 12 actually recruited at least one patient. To be included, patients had to have an advanced cancer with a surgically inoperable bowel obstruction and to have received no specific anticancer therapy within the preceding 28 days. They had to fulfil at least three of the following criteria: vomiting at least twice a day; colicky abdominal pain; no flatus for 12 h or more; no stool for at least 4 days, faecal impaction being excluded; intestinal distension; air–fluid levels or absence of gas in the colon on an abdominal radiograph. Patients were randomized in three groups to receive either a placebo for 3 days (group A), or methylprednisolone 240 mg daily for 3 days (group B) or methylprednisolone 40 mg daily for 3 days (group C). Symptoms were assessed daily but success or failure of the treatment was assessed on day 4, according to the disappearance or persistence of symptoms. Fifty-eight patients were randomized, of whom 52 were able to be evaluated. Details of symptoms and associated treatments are described below. Of 40 patients without a nasogastric tube, symptoms were relieved in 68% of cases versus 33% among placebo-treated patients (P = 0.047). In 12 patients who had a nasogastric tube already in place, the results are less significant (60% versus 33% with P = 0.080). Because of the small sample size, no conclusions can be reached about the relative efficacy of low versus high-dose treatment regimes.

Propagation of a high-contrast subpicosecond (400–600 fs) relativistic (Iλ2 up to 2×1019 W⋅cm−2⋅μm2) laser pulse through long preformed overdense plasmas is experimentally studied. Transmission values up to 10% are measured in plasmas with initial peak densities above 10×nc. We compare these results with one-dimensional (1D) analytical calculations of the hole boring effect. It is shown that the ponderomotive force of the laser beam can push forward the overdense plasma, create a channel, and lead to transmission levels similar to the experimental ones.

Propagation of a high-contrast frequency-doubled subpicosecond (300 fs) relativistic (Iλ2 up to 5×1018 W⋅cm−2⋅μm2) laser pulse through thin and initially solid foils is studied. Transmission values up to 10% are measured through targets with initial near solid densities. The strong intensity threshold observed for the transmitted energy is correlated with clear modifications of the transmitted and reflected spectra, electron generation, and beam imaging. Two-dimensional Cartesian particle-in-cell (PIC) simulations that qualitatively reproduce the experimental results suggest specific rapid heating of the thin targets by fast electrons, plasma expansion, and density decrease to relativistically transmissive conditions during the pulse.

The formation and evolution of density channels created by the interaction of a short bright (600 fs, $5\ifmmode\times\else\texttimes\fi{}{10}^{18}\mathrm{W}{\mathrm{cm}}^{\ensuremath{-}2}\ensuremath{\mu}{\mathrm{m}}^{2}$) laser pulse with a preformed plasma are studied by means of experiments and 2D particle-in-cell (PIC) simulations. Hollow density channels are observed by interferometry, and a fast radial expansion $(5\ifmmode\times\else\texttimes\fi{}{10}^{8}\mathrm{cm}/\mathrm{s})$ is measured. Magnetic fields around 50 MG inferred from Faraday rotation measurements suggest the occurrence of self-focusing. The PIC simulations support this hypothesis and show ion depletion during the laser pulse as well as radial expansion in agreement with experiments.

The stability of an electronic plasma in a large-amplitude dipolar field is analyzed. In such a wave the relativistic electron mass variation must be taken into account and in an overdense plasma an instability arises. The corresponding weakly relativistic theory of Tsintsadze [Sov. Phys. JETP 32, 684 (1971)] is extended to the fully relativistic regime. The growth rate of the instability can attain a significant fraction of the dipolar field frequency. The relevance of this instability to the fast ignitor concept is discussed.

Direct observations of secondary Langmuir waves produced by the parametric decay instability of primary Langmuir waves are presented. The measurements have been obtained using Thomson scattering of a short-wavelength probe laser beam and are resolved in time, space, frequency, and wave number. The primary Langmuir waves were driven by stimulated Raman scattering (SRS) of a smoothed laser beam in a preformed plasma. Measurements of the amplitude of the density fluctuations associated with primary and secondary Langmuir waves show that the threshold of the Langmuir decay instability (LDI) is close to the threshold of the Raman instability. This is in agreement with theoretical predictions. However, the ratio of amplitudes of the density fluctuations associated with both secondary and primary Langmuir waves does not agree with existing theories of SRS saturation due to LDI cascading and/or strong Langmuir turbulence in homogeneous plasmas. An explanation based on the interaction beam intensity distribution produced by the random phase plate in the plasma is discussed.

The dispersion relation for electron parametric instabilities of a circularly polarized laser wave of arbitrary intensity is established without restrictions on the plasma density. It is obtained in an implicit analytical form and solved numerically. The well-known stimulated Raman scattering, relativistic modulational instability, relativistic filamentation instability, and two-plasmon decay are recovered at low intensity. Their behavior in the ultrarelativistic regime is characterized by a wide extent of the unstable region in the wave vector space, with growth rates equal to a fraction of the laser frequency, and a strong harmonic generation. Particle-in-cell simulations confirm these results and show that the instability leads to a very strong heating of the plasma.

The results of a systematic study of the propagation of very high-intensity laser pulses through slabs of plasma of several tens of microns are presented. One-dimensional and two-dimensional electron parametric instabilities are evidenced. They lead to a rapid longitudinal and transverse heating, and to filamentary structures which progressively merge. The heating results in highly energetic electrons with energy of several tens of MeV. Correlatively, a strong attenuation rate of the electromagnetic wave is observed. {copyright} {ital 1997} {ital The American Physical Society}

A general dispersion relation is given for electron parametric instabilities of an ultraintense circularly polarized wave propagating in a plasma. It is valid for any plasma density and wave intensity and corresponds to a generalization of the Raman, relativistic modulational, relativistic filamentation, and two-plasmons instabilities. Its numerical resolution shows different zones of instability in the wave vector space. At high intensities, the zones extend and merge, with growth rates equal to a fraction of the wave frequency. At close-to-critical density and high intensity the instability leads to strong harmonic emission. Particle-in-cell simulations confirm the analytical results.

Low‐order mode coupling equations are used to describe recent computer simulations of resistive‐g turbulent convection that show bifurcations for the onset of steady and pulsating sheared mass flows. The three convective transport states are identified with the tokamak confinement regimes called low‐mode (L‐mode), high‐mode (H‐mode), and edge‐localized modes (ELMs). The first bifurcation (L→H) and the second bifurcation (H→ELMs) conditions are derived analytically and compared with direct solutions of the 6‐ODE mode coupling equations. First an exact expression is given for the energy transfer rate from the fluctuations to the sheared mass flow through the triplet velocity correlation function. Then the time scale expansion required to derive the Markovian closure formula is given. Markovian closure formulas form the basis for the thermodynamic‐like L–H models used in several recently proposed models.

Due to relativistic effects, a large amplitude electromagnetic wave can propagate in a classically overdense plasma with ω2p≳ω2≳ω2p/γ, where ωp is the plasma frequency, ω the laser frequency, and γ the relativistic factor of an electron in the laser field. Particle‐in‐cell simulations are used to study the interaction of an ultrahigh intensity laser pulse in normal incidence on a one‐dimensional preformed plasma layer. Both electrons and ions dynamics are included. The width of the layer is 10 to 30 μm and the plasma is characterized by (ωp/ω)2=1.5. During the penetration of the electromagnetic wave a large longitudinal electric field is generated. It results in a strong longitudinal heating of electrons which reach relativistic temperatures. This heating further lowers the effective plasma frequency ωp/γ so the layer becomes almost transparent after the plasma crossing by the wave front. Velocity of the wave front, reflection and transmission rates are studied as functions of the incident energy flux, th...

An original experimental apparatus of microwave plasma-assisted chemical vapour deposition is used to produce large cylindrical plasmas. The microwave electromagnetic field propagation is studied experimentally and theoretically in the plasma chamber. Electric field measurements confirm this calculation. The electronic density distribution is calculated in a second way from transport equations using a perturbation method. A validation of the model is obtained by measuring particle densities using a Langmuir probe.

Characterisation of genetic diversity in a large number of European pig populations has been undertaken with EC support. The populations sampled included local (rare) breeds, national varieties of the major international breeds, commercial lines and the Chinese Meishan breed. A second phase of the project will sample a further 50 Chinese breeds. Neutral genetic markers (AFLP and microsatellites), with individual or bulk typing, were used and compared.DNA from 59 European pig populations was extracted on samples of about 50 individuals per population. Individuals were typed for 50 microsatellites and for 148 AFLP bands. A subset of 25 populations was typed for 20 microsatellites on pools of DNA. Allele frequencies were estimated by direct allele counting for the co-dominant markers. Frequencies of AFLP negative alleles (absent bands) were obtained by taking the square root of absent band frequencies. Within-breed variability was summarised using standard statistics: expected and observed heterozygosity, mean observed and effective numbers of alleles, and F statistics. Between-breed diversity analysis was based on a bootstrapped Neighbor-Joining (NJ) tree derived from Reynolds distances (DR). The standard distance of Nei (DS) was also calculated.

A large amplitude electromagnetic wave propagating in a plasma is known to be subject to severe modulational and Raman instabilities. Previous works were devoted to the weakly relativistic limit and applied mainly to a cold underdense plasma. One extends these works to include the fully relativistic limit for a circularly polarized light for which one derives the dispersion relation in a one‐dimensional plasma. The characteristics of the instabilities are also calculated in the case where the plasma is classically overdense, with 1

Particle transport across braided magnetic surfaces is studied by using simple field and collision models. Diffusion along and across field lines is taken into account. A general variational principle is established. It provides a useful guide for numerical computations. In a special case an explicit formula for the diffusion coefficient is obtained. Several diffusion regimes are clearly identified, and their domain of validity is determined. A new form of the diffusion coefficient has to be introduced in the long‐mean‐free‐path regime.

The passive convection of Lagrangian points by a 2D compressible two-fluids flow is investigated numerically on a massively parallel computer. This numerical simulation concerns the Rayleigh-Taylor instability [1]. We compute the fractal dimension of this set of tracer particles located along the interface between the two fluids. A first result is that this dimension reaches a stationary value. Then this result is used to determine the effective opacity of the mixture.

We study the angular distribution of relativistic electrons generated through laser-plasma interaction with pulse intensity varying from ${10}^{18}\text{ }\text{ }\mathrm{W}/{\mathrm{cm}}^{2}$ up to ${10}^{21}\text{ }\text{ }\mathrm{W}/{\mathrm{cm}}^{2}$ and plasma density ranging from 10 times up to 160 times critical density with the help of 2D and 3D particle-in-cell simulations. This study gives clear evidence that the divergence of the beam is an intrinsic property of the interaction of a laser pulse with a sharp density gradient. It is entirely due to the excitation of large static magnetic fields in the layer of interaction. The energy deposited in this layer increases drastically the temperature of the plasma independently of the initial temperature. This makes the plasma locally collisionless and the simulation relevant for the current experiments.

Of the work: evaluation of a multidisciplinary strategy and a prospective medicosurgical protocol for the treatment of occlusion due to unresectable peritoneal carcinomatosis.All the included patients had occlusion and intraabdominal carcinomatosis. None could benefit a curative treatment. 75 patients were included for 80 episodes of intestinal obstruction. The protocol involved three successive therapeutic phases. (i) Treatment during five days by corticosteroids associated to antiemetic agents, anticholinergic antisecretory agents, and analgesics as needed (Phase I); (ii) In the event of refractory occlusive symptoms treatment by somatostatin analog during 3 days (phase II); (iii) If this treatment was ineffective a gastrostomy was performed (phase III).Median survival was 31 days. Outcome showed that for the 80 episodes of obstruction, phase I medical treatment enabled relief in 50 cases (63%) and phase II medical treatment (somatostatin) enabled relief in 11 cases (14%). 10 more patients (13%) were relieved by the gastrostomie and one by a duodenal endoprothesis. Symptom control without a long-term nasogastric tube was achieved for 72 of the 80 episodes (90%). Fifty-eight episodes (72% of overall total) were controlled for 10 days or less. Median time to gastrostomy was 17 days. Eight patients experienced persistent vomiting and required a nasogastric aspiration until death.This multidisciplinary approach between Palliative Care and Specialized Medical and Surgical teams enabled relief of the occlusive symptoms for 90% of the patients of the study. The protocol was useful for the caregivers for the management of terminally ill patients. To enhance these results, it would be necessary to shorten the delay of relief, which has been longer than ten days for one third of the patients. The simplification of the protocol including two steps instead of three is on study.

Contagious bovine pleuropneumonia (CBPP) is a contagious infection of cattle caused by a mycoplasma, M. mycoides subsp. mycoides SC (MmmSC). It induces lesions of pleuropneumonia in acute cases and the formation of pulmonary "sequestra" in chronic cases. The disease is prevalent mostly in Africa, where it is responsible for high losses, but it has also been sporadically present in Southern Europe until 1999. Vaccination is now prohibited in most countries except in Africa. An empirical "inoculation" procedure was developed as early as 1852 in Europe but it may have been used even earlier in Africa. The inoculation of pleural fluid was performed at the tip of the tail in Europe and on the bridge of the nose in Africa. It conferred good protection but induced a high number of fatal cases. Various inactivated preparations have been tested in the past with inconclusive results leading sometime to some protection and some other time to a sensitisation of the immunised animals. Such preparations have never been used in the field. Attenuated MmmSC strains have been developed in the 1950s and used extensively in the field both in Africa and Australia. The best known vaccine strains are KH3J, T1/44 and T1sr. Vaccination campaigns have succeeded in reducing considerably the CBPP prevalence in these two continents but eradication was achieved in Australia only by switching to strict measures of animal movement control and a stamping-out policy. The search for new CBPP vaccines has become a major issue for African countries that are facing an increase in outbreaks. The rationale for this search is based on a better understanding of the mycoplasma virulence mechanisms that could lead to a targeted attenuation of MmmSC strains. It is also based on a better understanding of the bovine immune response that may be driven to a pathogenic inflammatory response or conversely to a better balanced response leading to protection.

The end-point of this survey was to evaluate the number of patients in advanced or terminal phase of a life-threatening disease and hospitalised in the university hospital in Grenoble on a given day. The secondary end-points were determination of the profile of patients undergoing palliative care and the therapeutic charge they represented for the hospital in order to develop optimal medico-psycho-social responses adapted to the needs of this population, their family and friends and the teams of health professionals who treat them.The survey was based on a questionnaire including 106 items and one open question, filled-in by a physician and the nurses of the hospital, together with the interviewer.Out of the 1495 patients hospitalised in the hospital centre (84% occupation), 114 patients were included in the study, i.e., 8% of the total number of patients present. Patients' mean age was of 70 (21x98); 40% were aged over 75. The principle motivation for hospitalisation was an acute medical problem (54%) followed by the impossibility of remaining at home (42%); 32% of the patients were hospitalised for a scheduled follow-up or treatment. The pathologies most frequently observed were cancer (61%) and neuro-degenerative disorders (28%). In our study, this category of patient exhibited a complex and heavy medico-psycho-social profile. It also revealed, when compared with a similar study conducted in 1996 at the Pitié-Salpêtrière hospital, that the identification of an advanced or terminal phase of a disease was generally late and probably prohibited the patients, their families and the nursing staff from access to specific accompaniment.Our results demonstrate the need for palliative care unit (with beds) in large establishments such as the university hospital in Grenoble, in the centre of large towns. Although not all terminally ill patients require a specialised palliative care unit, we feel that the creation of such units will be mandatory in the years to come, if only because of public pressure or necessity.

Le fentanyl administre en transmuqueux (OTFC) a prouve son efficacite dans le traitement des acces douloureux paroxystiques (ADP). Quatre formes galeniques existent: Actiq®, Abstral®, Effentora® et Instanyl®. Aucune n'a temoigne d'une meilleure efficacite. Objectif de l'etude : comparer la satisfaction des patients et des soignants pour chaque forme galenique afin d'identifier des criteres utilisables en pratique. Etude observationnelle, prospective ; Duree : 4 mois et demi. Patients atteints d'un cancer et traites par OTFC dans l'ADP. Entretiens de patients au cours duquel ils remplissent "Pain Treatment Satisfaction Scale (PTSS)" et des items de maniabilite : efficacite, temps a agir, tolerance, ouverture de l'emballage, caracteres organoleptiques, autonomie, praticite globale. Entretiens de soignants egalement. Critere de jugement principal : Comparaison des scores de satisfaction pour chaque groupe. Criteres secondaires : Comparaison des scores de tolerance et de maniabilite. Resultats : 71 patients inclus: 29 Abstral®, 27 Effentora®, 15 Instanyl®, aucun Actiq®. 1-Aucune difference significative sur les criteres principaux et secondaires chez les patients par manque de puissance (p=34%). Difference significative chez les soignants : Abstral® plus pratique, plus facile a ouvrir et meilleur gout qu'Effentora®. Instanyl® plus rapide qu'Effentora®. 2-Entretiens patients : Les formes "comprime" sont appreciees car elles sont petites et discretes. Abstral® est une forme polyvalente : pratique, rapide d'action. Effentora® est long a faire fondre. Instanyl® est interessant lorsque la voie orale est inaccessible. 3- Entretiens soignants : L'administration d'Instanyl® est complexe car absence de compteur de dose, pas de materialisation de la prise, soucis organisationnels dans le service : tracabilite, abus... Le nombre de forme galenique est suffisant. Une experience clinique est indispensable afin d'adapter la bonne forme a chaque patient.

The new opioids and the new galenic forms, now available in France, require an update in practitioners' knowledge. The purpose of the present study is to help those prescribing select the appropriate opioid and its galenic form for pain relief.Presentation of pharmacological properties of opioids (mechanisms, pharmacokinetics and pharmacovigilance). Presentation of indications, modes of prescription and use of main opioids for pain (especially cancer pain). Examples for calculating required drug dosage depending on the clinical situation and the route of administration. Symptomatic treatments of the main undesirable side effects of the opioids, and actions to be taken in the event of accidental overdose.Oral morphine is the treatment first recommended for nociceptive pain insufficiently relieved by WHO level I and II analgesics. The new immediate-release galenic forms allow morphine titration and the treatment of breakthrough pain. Transmucosal fentanyl, soon available in France, is recommended for breakthrough pain in patients already under opioid treatment: it gives more rapid relied starting after only 5 minutes and it only acts for a short time. Transdermal fentanyl is indicated for stable cancer pain. It is particularly suitable when oral and injectable morphine routes are not available, or for patients with severe constipation. Hydromorphone is the first opioid recommended in France for severe cancer pain when morphine resistance exists or uncontrolled side effects are present (opioid rotation). The new opioids and the new galenic forms widen the range of therapeutic possibilities. Their use is well codified for cancer pain and must still undergo clinical trials for chronic non-cancer pain. When correctly indicated, opioid selection provides a considerable advance in pain management.

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.

Thomson scattering measurements are presented which demonstrate conclusively the occurrence of the Langmuir decay instability (LDI) in a laser-produced plasma experiment. Both products of the instability, the ion acoustic wave and the electron plasma wave, were simultaneously observed and identified with their spectral characteristics. The secondary decay of the LDI-generated electron plasma wave, into another Langmuir wave and an ion acoustic wave, has been observed for the first time. The connection with growth and saturation of the stimulated Raman instability is discussed.

The interaction of ultraintense laser beams with underdense plasma slabs has been investigated with two-dimensional particle-in-cell numerical simulations, showing a strong absorption and a correlatively low transmission. Energetic electrons in the multi-MeV range are produced. At very high intensities the plasma transparency is recovered. These results are interpreted in terms of the development of electron parametric instabilities in the self-consistently heated plasma.

The general dispersion relation for electron parametric instabilities of an ultra-intense circularly polarized laser wave is established for arbitrary plasma density. It corresponds to a generalization of the stimulated Raman scattering instability, the relativistic modulational instability, the relativistic filamentation instability, and the two plasmons decay instability. In the relativistic regime the generalized instability is characterized by a wide extent of the unstable region in the wave vector space, with growth rates reaching a fraction of the laser frequency, and a strong harmonic generation. One-dimensional and two-dimensional particle-in-cell simulations confirm these results. In particular a systematic study of the propagation of very intense laser pulses through slabs of plasma of several tens of microns are presented. The instability leads to a rapid longitudinal and transverse electron heating, and to filamentary structures which progressively merge in a nonlinear stage. The heating results in highly energetic electrons with energy of several tens of MeV. Correlatively, a strong attenuation rate of the electromagnetic wave is observed.

An electromagnetic wave is expected to propagate through an overdense plasma, provided that its amplitude is large enough to bring the electron motion into the relativistic regime. We study this induced transparency by using 1D and 2D particle simulations. We find that large chaotic longitudinal electric fields are generated and strong plasma heating takes place during the propagation. This behavior is attributed to parametric instabilities. In order to support this interpretation, the modulational and Raman instabilities of a relativistic electromagnetic wave are studied analytically as well as with the help of particle simulations. In addition it is found that a finite width beam is strongly self focused

Coronary angioplasty is sometimes thought to be insufficiently validated considering the considerable development it has undergone and its place in modern cardiological practice. Nevertheless, several randomised clinical trials comparing angioplasty with medical therapy in stable angina (ACME) and with surgical treatment in stable and unstable angina (RITA) have provided more scientific support for the technique. The serious perioperative complications have become rare, the limiting factor being restenosis which is responsible for a large number of clinical recurrences and the reappearance of documented myocardial ischaemia. It is therefore logical to make restenosis the first objective of evaluation of PTCA. There are two possible approaches to this problem. The first relies on automatic quantitative operator-independent angiography as a gold standard. However, this method is methodologically complex, technically fastidious and only takes into consideration the anatomical appearances, the correlations with clinical outcome and prognosis of which are poor. It allows measurement of the amplitude of the process which is an unquestionable advantage, but it is only a partial view of the problem. The second method considers that only stenosis causing ischaemia is significant and that the criterion of evaluation should be the rate of new events and that the necessity of repeated attempts at revascularisation is the criterion of failure of the method. This overlooks the possibility of an anti-restenosis drug producing clinical results independents of its anatomical effect. Both methods have their advantages and drawbacks, which necessitates using them both in all trials of new tools or new molecules designed to prevent restenosis.

Acute myocardial infarction is the result of sudden coronary occlusion in the absence of a collateral circulation. There main factors are required for this to occur: an acute parietal lesion on a stenosis of variable, sometimes minor, importance; local coronary vasoconstriction and a platelet and fibrin thrombus. Parietal fissuration is the commonest "trigger" of coronary spasm and the thrombotic cascade. All factors of coronary occlusion are potentially reversible--vasodilation--platelet anti-aggregation--physiological fibrinolysis--remodeling and cicatrisation of the plaque, thereby explaining cases of spontaneous regression of occlusion (10% at 1 hour; 20% at 6 hours; 30% at 24 hours; 50 to 70% at 1 year). The pathogenesis of myocardial infarction with angiographically normal coronary arteries may be reviewed and attributed to acute parietal fissuration at a non-significant or angiographically undetectable plaque resulting in occlusive thrombosis. In this case, the role of other pathogenic factors is also discussed (diabetes, oral contraception, haemostatic abnormalities, platelet disorders...).

Myocardial infarction is an anatomical and therefore functional amputation of some of the myocardial tissues. Moments after acute coronary occlusion, a cascade of metabolic, mechanical and electrical ischaemia related events is observed. Contraction stops and regional left ventricular akinesis (then dyskinesis) occurs in the zone at risk of irreversible myocardial damage. This is partially compensated by hyperkinetic motion of non-ischaemic myocardium. The degree of alteration of the global ejection fraction is the resultant of these akinetic and hyperkinetic wall motions. It is lower in cases of anterior myocardial infarction, of occlusion of the proximal segment of the left anterior descending artery and of multivessel disease. Its eventual outcome depends on coronary blood flow. If the artery responsible is recanalized early, the global ejection fraction stabilises or improves. When this does not happen, the global ejection fraction decreases. The end-diastolic volume, an indicator of left ventricular remodeling, increases in relation to the size of the infarct and to the persistence of coronary artery occlusion. The delay before the appearance of the first irreversible lesions, the rate of their propagation within the myocardial wall and the presence of reperfusion lesions are poorly understood factors in the clinical setting and influence the efficacy of methods of myocardial protection.

A systematic study of a high-frequency electron drift instability is presented. It has very large wave numbers corresponding to wavelengths close to the electron gyroradius. The three-dimensional dispersion relation is derived for a model of a crossed electric and magnetic field configuration existing in the Hall thruster. It is shown that the instability develops in packets of oblique unstable modes perpendicular to the magnetic field. The evolution of the instability is also studied for distorted electron distribution functions obtained in particle-in-cell simulations.