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Background Infective endocarditis is associated with significant morbidity and mortality. Natural history of vegetations under antibiotic treatment is poorly understood, and the long-term prognostic impact of residual vegetations after complete treatment remains unknown. Purpose To evaluate prognostic impact of residual vegetation after complete and successful antibiotic treatment. Methods In a retrospective cohort study, we included 134 patients hospitalized for infective endocarditis in a tertiary center, with presence of vegetation at diagnosis, treated with complete antibiotic therapy, from January 2013 to December 2017. The follow-up started at the end of antibiotic treatment, when healing was complete. Presence or absence of residual vegetation was assessed at this time. The primary endpoint was a composite of the occurrence of embolic event, recurrence of endocarditis or death from any cause. Results Eighty-five patients were men (63%), mean age was 69 ± 15-years-old and median follow-up was 16.3 (IQR: 5 to 30) months. Sixty-six (49%) patients have residual vegetations at the end of treatment. The primary endpoint occurred in 23 patients (35%) in the group with residual vegetation and in 16 patients (24%) without, which was not statistically relevant (OR 1.74; 95% confidence interval 0,82–3,67; P = 0.15). By univariate analysis, the occurrence of the primary endpoint was associated with an increasing size of vegetation under treatment (OR 5.94;95% CI 1.52–23.15; P = 0.01), or a size of vegetation over 10 mm at the end of treatment (OR 3.47;95% CI 1,19–10,08; P = 0.02); however, it was not corroborated by multivariate analysis. There was a trend of the antiplatelet therapy to be protective of the occurrence of the primary endpoint (0R = 0.30; 95% CI 0.09–0.99; P = 0.04) ( Table 1 , Fig. 1 ). Conclusions Persistence of vegetation after healing is frequent but has no clear prognostic impact in patients treated for infective endocarditis.

An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L–H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced Dα H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Peer Reviewed "Article signat per més de 50 autors/es: U. Stroth, D. Aguiam, E. Alessi, C. Angioni, N. Arden, R. Arredondo Parra, V. Artigues, O. Asunta, M. Balden, V. Bandaru, A. Banon-Navarro, K. Behler, A. Bergmann, M. Bergmann, J. Bernardo, M. Bernert, A. Biancalani, R. Bielajew, R. Bilato, G. Birkenmeier, T. Blanken, V. Bobkov, A. Bock, T. Body, T. Bolzonella, N. Bonanomi, A. Bortolon, B. Böswirth, C. Bottereau, A. Bottino, H. van den Brand, M. Brenzke, S. Brezinsek, D. Brida, F. Brochard, C. Bruhn, J. Buchanan, A. Buhler, A. Burckhart, Y. Camenen, B. Cannas, P. Cano Megias, D. Carlton, M. Carr, P. Carvalho, C. Castaldo, M. Cavedon, C. Cazzaniga, C. Challis, A. Chankin, C. Cianfarani, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, L. Colas, G. Conway, S. Costea, D. Coster, T. Cote, A.J. Creely, G. Croci, D.J. Cruz Zabala, G. Cseh, A. Czarnecka, I. Cziegler, O. D'Arcangelo, A. Dal Molin, P. David, C. Day, M. de Baar, P. de Marné, R. Delogu, S. Denk, P. Denner, A. Di Siena, J.J. Dominguez Palacios Durán, D. Dunai, A. Drenik, M. Dreval, R. Drube, M. Dunne, B.P. Duval, R. Dux, T. Eich, S. Elgeti, A. Encheva, K. Engelhardt, B. Erdös, I. Erofeev, B. Esposito, E. Fable, M. Faitsch, U. Fantz, M. Farnik, H. Faugel, F. Felici, O. Ficker, S. Fietz, A. Figueredo, R. Fischer, O. Ford, L. Frassinetti, M. Fröschle, G. Fuchert, J.C. Fuchs, H. Fünfgelder, S. Futatani, K. Galazka, J. Galdon-Quiroga, D. Gallart Escolà, A. Gallo10, Y. Gao11, S. Garavaglia3, M. Garcia Muñoz16, B. Geiger21, L. Giannone1, S. Gibson32, L. Gil2, E. Giovannozzi18, S. Glöggler1, M. Gobbin8, J. Gonzalez Martin, T. Goodman, G. Gorini, T. Görler, D. Gradic, G. Granucci, A. Gräter, H. Greuner, M. Griener, M. Groth, A. Gude, L. Guimarais, S. Günter, G. Haas, A.H. Hakola, C. Ham, T. Happel, N. den Harder, G. Harrer, J. Harrison, V. Hauer, T. Hayward-Schneider, B. Heinemann, T. Hellsten, S. Henderson, P. Hennequin, A. Herrmann, E. Heyn, F. Hitzler, J. Hobirk, K. Höfler, J.H. Holm, M. Hölzl, C. Hopf, L. Horvath, T. Höschen, A. Houben, A. Hubbard, A. Huber, K. Hunger, V. Igochine, M. Iliasova, T. Ilkei, K. Insulander Björk, C. Ionita-Schrittwieser, I. Ivanova-Stanik, W. Jacob, N. Jaksic, F. Janky, A. Jansen van Vuuren, A. Jardin, F. Jaulmes, F. Jenko, T. Jensen, E. Joffrin, A. Kallenbach, S. Kálvin, M. Kantor, A. Kappatou, O. Kardaun, J. Karhunen4, C.-P. Käsemann, S. Kasilov, A. Kendl, W. Kernbichler, E. Khilkevitch, A. Kirk, S. Kjer Hansen, V. Klevarova, G. Kocsis, M. Koleva, M. Komm, M. Kong, A. Krämer-Flecken, K. Krieger, A. Krivska, O. Kudlacek, T. Kurki-Suonio, B. Kurzan, B. Labit, K. Lackner, F. Laggner, A. Lahtinen, P.T. Lang, P. Lauber, N. Leuthold, L. Li, J. Likonen, O. Linder, B. Lipschultz, Y. Liu, A. Lohs, Z. Lu, T. Luda di Cortemiglia, N.C. Luhmann, T. Lunt, A. Lyssoivan, T. Maceina, J. Madsen, A. Magnanimo, H. Maier, J. Mailloux, R. Maingi, O. Maj, E. Maljaars, P. Manas, A. Mancini, A. Manhard, P. Mantica, M. Mantsinen, P. Manz, M. Maraschek, C. Marchetto, L. Marrelli, P. Martin, A. Martitsch, F. Matos, M. Mayer, M.-L. Mayoral, D. Mazon, P.J. McCarthy, R. McDermott, R. Merkel, A. Merle, D. Meshcheriakov, H. Meyer, D. Milanesio, P. Molina Cabrera, F. Monaco, M. Muraca, F. Nabais, V. Naulin, R. Nazikian, R.D. Nem, A. Nemes-Czopf, G. Neu, R. Neu, A.H. Nielsen, S.K. Nielsen, T. Nishizawa, M. Nocente, J.-M. Noterdaeme, I. Novikau, S. Nowak, M. Oberkofler, R. Ochoukov, J. Olsen, F. Orain, F. Palermo, O. Pan, G. Papp, I. Paradela Perez, A. Pau, G. Pautasso, C. Paz-Soldan, P. Petersson, P. Piovesan, C. Piron, U. Plank, B. Plaum, B. Plöck, V. Plyusnin, G. Pokol, E. Poli, L. Porte, T. Pütterich, M. Ramisch, J. Rasmussen, G. Ratta, S. Ratynskaia, G. Raupp, D. Réfy, M. Reich1, F. Reimold, D. Reiser, M. Reisner, D. Reiter, T. Ribeiro, R. Riedl, J. Riesch, D. Rittich, J.F. Rivero Rodriguez, G. Rocchi, P. Rodriguez-Fernandez, M. Rodriguez-Ramos, V. Rohde, G. Ronchi, A. Ross, M. Rott, M. Rubel, D.A. Ryan, F. Ryter, S. Saarelma, M. Salewski, A. Salmi, O. Samoylov, L. Sanchis Sanchez, J. Santos, O. Sauter, G. Schall, K. Schlüter, K. Schmid, O. Schmitz, P.A. Schneider, R. Schrittwieser, M. Schubert, C. Schuster, T. Schwarz-Selinger, J. Schweinzer, E. Seliunin, A. Shabbir, A. Shalpegin, S. Sharapov, U. Sheikh, A. Shevelev, G. Sias, M. Siccinio, B. Sieglin, A. Sigalov, A. Silva, C. Silva, D. Silvagni, J. Simpson, S. Sipilä, E. Smigelskis, A. Snicker, E. Solano, C. Sommariva, C. Sozzi, G. Spizzo, M. Spolaore, A. Stegmeir, M. Stejner, J. Stober, E. Strumberge1, G. Suarez Lopez, H.-J. Sun, W. Suttrop, E. Sytova, T. Szepesi, B. Tál, T. Tala, G. Tardini, M. Tardocchi, D. Terranova, M. Teschke, E. Thorén, W. Tierens, D. Told, W. Treutterer, G. Trevisan, E. Trier, M. Tripský, M. Usoltceva, M. Valisa, M. Valovic, M. van Zeeland, F. Vannini, B. Vanovac, P. Varela, S. Varoutis, N. Vianello, J. Vicente, G. Verdoolaege, T. Vierle, E. Viezzer, I. Voitsekhovitch, U. von Toussaint, D. Wagner, X. Wang, M. Weiland, A.E. White, M. Willensdorfer, B. Wiringer, M. Wischmeier, R. Wolf, E. Wolfrum, Q. Yang, Q. Yu, R. Zagórski, I. Zammuto, T. Zehetbauer, W. Zhang, W. Zholobenko, M. Zilker, A. Zito, H. Zohm, S. Zoletnik and the EUROfusion MST1 Team "

The tokamak à configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to address critical issues in preparation for ITER and a fusion power plant. For the 2019–20 campaign its configurational flexibility has been enhanced with the installation of removable divertor gas baffles, its diagnostic capabilities with an extensive set of upgrades and its heating systems with new dual frequency gyrotrons. The gas baffles reduce coupling between the divertor and the main chamber and allow for detailed investigations on the role of fuelling in general and, together with upgraded boundary diagnostics, test divertor and edge models in particular. The increased heating capabilities broaden the operational regime to include T e/T i ∼ 1 and have stimulated refocussing studies from L-mode to H-mode across a range of research topics. ITER baseline parameters were reached in type-I ELMy H-modes and alternative regimes with ‘small’ (or no) ELMs explored. Most prominently, negative triangularity was investigated in detail and confirmed as an attractive scenario with H-mode level core confinement but an L-mode edge. Emphasis was also placed on control, where an increased number of observers, actuators and control solutions became available and are now integrated into a generic control framework as will be needed in future devices. The quantity and quality of results of the 2019–20 TCV campaign are a testament to its successful integration within the European research effort alongside a vibrant domestic programme and international collaborations.

Background Maintenance ART with dolutegravir-based dual regimens have proved their efficacy among HIV-1-infected subjects in randomized trials. However, real-life data are scarce, with limited populations and follow-up. Objectives We assessed virological failure (VF) and resistance-associated mutations (RAMs) on dolutegravir maintenance regimens in combination with rilpivirine or with lamivudine or emtricitabine (xTC) and analysed the factors associated with VF. Methods Between 2014 and 2018, all HIV-1-infected adults included in the Dat’AIDS cohort and starting dolutegravir/rilpivirine or dolutegravir/xTC as a maintenance dolutegravir-based dual regimen were selected. VF was defined as two consecutive HIV RNA values >50 copies/mL or a single value >400 copies/mL. We compared cumulative genotypes before initiation of a maintenance dolutegravir-based dual regimen with genotype at VF. Results We analysed 1374 subjects (799 on dolutegravir/rilpivirine and 575 on dolutegravir/xTC) with a median follow-up of 20 months (IQR = 11–31) and 19 months (IQR = 11–31), respectively. VF occurred in 3.8% (n = 30) of dolutegravir/rilpivirine subjects and 2.6% (n = 15) of dolutegravir/xTC subjects. Among subjects receiving dolutegravir/rilpivirine, two genotypes harboured emerging RAMs at VF: E138K on NNRTI (n = 1); and E138K+K101E on NNRTI and N155H on INSTI (n = 1). Among subjects receiving dolutegravir/xTC, no new RAM was detected. The only predictive factor of VF on dolutegravir/rilpivirine was the history of failure on an NNRTI-based regimen (adjusted HR = 2.97, 95% CI = 1.28–6.93). No factor was associated with VF on dolutegravir/xTC. Conclusions In this large real-life cohort, dolutegravir/rilpivirine and dolutegravir/xTC sustained virological suppression and were associated with a low rate of VF and RAM emergence. Careful virological screening is essential before switching to dolutegravir/rilpivirine in virologically suppressed patients with a history of NNRTI therapy.

BACKGROUND Preventive strategies for invasive aspergillosis (IA) have still not been determined in heart transplant recipients whereas IA leads to a high mortality rate at 12 months posttransplantation. The use of voriconazole or echinocandins was proposed but can favor emergence of Aspergillus or Candida sp. resistant strains or promote neurological and liver disorders in some patients. OBJECTIVES To assess whether universal prophylaxis with weekly high-dose of liposomal amphotericin-B (L-AmB) can safely prevent IA in heart transplant recipients. PATIENTS/METHODS Retrospective before/after study that included 142 patients who received heart transplantation between 2010 and 2019 at the University Hospital of Toulouse (France). Weekly high dose of L-AmB (7.5 mg/kg/week) was used as universal prophylaxis from 2016 because of high environmental exposure to Aspergillus sp. and high incidence of IA. RESULTS Cumulative 1-year incidence of IA decreased from 23% to 5% after introduction of L-Amb prophylaxis. Multivariate analysis (Cox model) identified L-AmB prophylaxis as a protective factor against IA (hazard ratio [HR] 0.21 [95% confidence interval 0; 0.92], p = .04), whereas postoperative renal replacement therapy was associated with IA (HR 3.6 [95% confidence interval 1.38; 9.3], p = .001), after correction for confounding effects (induction regimen, methylprednisolone pulses and history of hematological malignancy). The incidence of acute kidney injury requiring renal replacement therapy was similar in the two groups, suggesting a low risk of kidney toxicity when L-AmB is used weekly. No patient developed severe kidney electrolyte loss nor L-AmB-related anaphylaxis. CONCLUSIONS Once-weekly high-dose L-AmB is safe and may prevent the development of IA after heart transplantation.

BackgroundIntegrase strand transfer inhibitors (INSTIs) are increasingly used in patients living with HIV due to their safety, effectiveness and high genetic barrier. However, an association with weight gain has recently been suggested and several cases of diabetes mellitus have been reported with raltegravir and dolutegravir. The long-time metabolic impact of these recent molecules remains unclear.ObjectivesTo assess if an INSTI as a third agent is statistically associated with new-onset diabetes mellitus compared with an NNRTI or a PI.Patients and methodsPatients undergoing first-line combined ART (cART) without diabetes at baseline were retrospectively included from the Dat’AIDS French cohort study (ClinicalTrials.gov NCT02898987). Incident diabetes mellitus was defined as a notification of new diabetes in the medical history, a glycated haemoglobin (HbA1c) level superior to 7.5% or the start of a diabetes therapy following the initiation of ART.ResultsFrom 2009 to 2017, 19 462 patients were included, among which 265 cases of diabetes mellitus occurred. Multivariate and survival analyses did not highlight an increase in new-onset diabetes in patients undergoing cART with an INSTI as a third agent compared with an NNRTI or a PI. BMI >30 kg/m2, age >37 years old (in survival analysis), black race or Hispanic ethnicity, arterial hypertension and AIDS were associated with a higher proportion of incident diabetes.ConclusionsINSTIs were not statistically associated with new-onset diabetes. However, clinicians should remain aware of this possible metabolic comorbidity, particularly in patients with a high BMI and older patients.

Background In late 2013, France was one of the first countries to recommend initiation of combination antiretroviral therapy (cART) irrespective of CD4 cell count. Methods To assess the impact of achieving the second and third Joint United Nations Programme on HIV/AIDS 90-90-90 targets (ie, 90% of diagnosed people on sustained cART, and, of those, 90% virologically controlled) on human immunodeficiency virus (HIV) incidence, we conducted a longitudinal study to describe the epidemiology of primary HIV infection (PHI) and/or recent HIV infection (patients with CD4 cell count ≥500/mm3 at HIV diagnosis; (PRHI) between 2007 and 2017 in a large French multicenter cohort. To identify changes in trends in PHI and PRHI, we used single breakpoint linear segmented regression analysis. Results During the study period, 61 822 patients were followed in the Dat’AIDS cohort; 2027 (10.0%) had PHI and 7314 (36.1%) had PRHI. The second and third targets were reached in 2014 and 2013, respectively. The median delay between HIV diagnosis and cART initiation decreased from 9.07 (interquartile range [IQR], 1.39–33.47) months in 2007 to 0.77 (IQR, 0.37–1.60) months in 2017. A decrease in PHI (−35.1%) and PRHI (−25.4%) was observed starting in 2013. The breakpoints for PHI and PRHI were 2012.6 (95% confidence interval [CI], 2010.8–2014.4) and 2013.1 (95% CI, 2011.3–2014.8), respectively. Conclusions Our findings show that the achievements of 2 public health targets in France and the early initiation of cART were accompanied by a reduction of about one-third in PHI and PRHI between 2013 and 2017. Clinical Trials Registration NCT02898987.

Effective, scalable mental health programs are greatly needed for older adults. In this study, Mood Lifters—a peer-led, community-based program promoting mental well-being—was adapted to more specifically address the needs of older adults. Two groups completed the 14-week program via Zoom. A total of 24 participants enrolled ( Mage = 72 years), with 20 (83%) completing the program. Compared to baseline, program completers showed significant improvements in depression symptoms ( p

International audience; Objectives: To characterize the clinical presentation and outcomes of invasive mold infections (IMI) in solid organ transplant (SOT) recipients.Methods: Inclusion of all SOT recipients with IMI diagnosed between 2008 and 2016 at a referral center for SOT. Univariable analyses identified factors associated with death at one year, and logistic regression models retained independent predictors.Results: Of the 1739 patients that received a SOT during this period, 68 developed IMI (invasive aspergillosis [IA] in 58). Cumulative incidence of IMI at 1 year ranged from 1.2% to 18.8% (kidney and heart transplantation, respectively). At baseline, compared with other IMI, the need for vasoactive drugs was more frequent in patients with IA. During follow-up, 35 patients (51%) were admitted to the ICU and required mechanical ventilation (n = 27), vasoactive drugs (n = 31), or renal replacement therapy (n = 31). The need for vasoactive drugs (OR 7.34; P = .003) and a positive direct examination (OR 10.1; P = .004) were independently associated with the risk of death at 1 year in patients with IA (n = 33; 57%) CONCLUSIONS: Characteristics of IMI at presentation varied according to the underlying transplanted organ and the mold species. Following IA, one-year mortality may be predicted by the need for hemodynamic support and initial fungal load

The favorable confinement properties of negative-triangularity (NT) tokamak configurations were discovered in the TCV tokamak in the late 1990s and were documented over the two following decades, through investigations of predominantly electron-heated plasmas in limited topologies. The most recent experimental campaign in TCV has marked a leap forward, characterized by the development of a variety of diverted NT shapes that are robustly stable with basic Ohmic heating. The application of auxiliary heating, directed now at both electrons and ions (using electron-cyclotron resonance heating as well as neutral-beam injection), has enabled the achievement of record performances for L-mode plasmas, with normalized β values reaching 2.8 transiently (as well as 2 in steady state, but reverting to a limited configuration) and with comparable ion and electron temperatures. The systematic confinement enhancement with NT is confirmed in these experiments. The L-mode existence space is broader than at positive triangularity, with only sporadic transitions to H-mode observed up to 1.4 MW heating power regardless of the magnetic-field-gradient direction relative to the X-point. These experiments are planned to be continued with even higher power following a heating-source upgrade.

Background Measurement of cardiac troponin (cTn) levels in blood is standard for diagnosis and risk stratification in cardiac emergencies. Purpose To investigate the causes, link to underlying coronary artery disease and prognostic value of cTn release in infective endocarditis (IE). Method Eighty-six consecutive patients hospitalized for acute IE, with at least one cTn drawn and a coronary angiogram performed, were reviewed retrospectively. Factors related to the increase of cTn above the 99th percentile or above 10 times normal (> 10N), as well as their prognostic impact, were assessed. Results The mean patient age was 63 + 14 years, the majority were men (n = 68, 79%) with staphylococcus IE (n = 34, 40%). Cardiac troponins were elevated above the 99th percentile for 74 (86%) patients and > 10N for 25 (29%) patients. There was no statistically significant correlation between elevated cTn and the presence of an underlying coronary artery disease ( Table 1 ). Cardiac troponin elevation above the 99th percentile was significantly associated with impaired renal function (P = 0.04) and staphylococcus infection (P = 0.02). A rise of cTn > 10N was significantly associated with acute pulmonary edema (P = 0.001), myocardial abscess (P = 0.01), staphylococcus (P = 0.0004), streptococcus (P = 0.008), and renal function (p = 0.0001). The average follow-up period was 919±816 days, and an elevation of cTn > 10 N had a clear prognostic impact (HR 2.38, 95%CI: 1.18–4.84, P = 0.01) ( Fig. 1 ). Conclusion Troponin elevation in IE is frequent and appears to be related to direct and indirect myocardial injury. It is associated with a poor prognosis.

Propionibacterium acnes endocarditis is rare and difficult to diagnose. We report a case of Propioniacterium acnes endocarditis revealed by a lower limb fasciitis.A 54-year-old patient presented with recurrent febrile myalgia of the lower limbs, that appeared three years after an aortic surgery (aortic valve sparing reimplentation and ascending aortic prosthesis implantation). Computer tomography showed fasciitis of both legs. Positron emission tomography showedIn patients with vascular prostheses, Propionibacterium acnes infection must be evoked face to an atypical inflammatory process. Very prolonged blood culture incubation is needed to identify the pathogen.

Introduction La vaccination par le vaccin ROR (2 doses a 12 et 18 mois) a permis une reduction drastique de l’incidence des oreillons en France. Cependant plusieurs epidemies ont ete rapportees dans des communautes bien vaccinees. Nous rapportons ici une telle epidemie d’oreillons dans un club de Rugby professionnel. Materiels et methodes Etude observationnelle, descriptive, rapportant les cas de parotidites bilaterales en rapport avec une infection par le virus ourlien survenus entre novembre 2019 et fevrier 2020 parmi les membres d’un club de Rugby. Verification du statut vaccinal de l’ensemble des exposes : patients consideres comme bien vaccines si avaient deja recu 2 doses de vaccin (tracees sur le carnet de sante). Les cas presentaient des signes cliniques compatibles avec la maladie. Apres elimination des diagnostics differentiels (enterovirus, EBV, CMV, VIH…), le diagnostic d’oreillons avait ete finalement porte par la positivite d’une PCR sur prelevements oropharynges realisee au centre de reference (Caen). Resultats Le nombre de personnes exposees etait de 57 joueurs, tous âges de moins de 31 ans (âge moyen : 24,7, âge maximal : 31). Vingt personnels du staff de l’equipe, âges de plus de 35 ans, ont egalement ete en contact avec des joueurs sans que des cas soient declares parmi eux. Le taux de patients correctement vaccines (2 doses) parmi les joueurs etait de 100 %. Au total, 14 joueurs ont presente des signes d’infection ainsi qu’une compagne de joueur. Les 15 malades etaient tous âges de moins de 31 ans et ont tous presentes une symptomatologie de parotidite bilaterale initiale avec fievre. Un des cas a presente une orchi-epididymite. Pour 3 de ces cas, une confirmation du diagnostic par PCR a ete realisee. Aucun des membres du staff, plus âges (> 35 ans), n’a ete infecte. Conclusion Deux doses de vaccins sont recommandees en France pour prevenir les Oreillons. Malgre cela, on note plusieurs cas d’epidemies dans des pays developpes dans des communautes bien vaccinees. Plusieurs facteurs semblent favoriser ces epidemies. En premier, une diminution du taux d’anticorps protecteurs avec le temps qui pourrait etre amelioree par une injection d’une troisieme dose de vaccin de facon systematique a l’âge adulte ou chez des cas contact. Un deuxieme facteur pourrait etre l’exposition a un inoculum important favorise par des contacts etroits. On remarque que la plupart des epidemies ont lieu dans des groupes de jeunes adultes avec des contacts tres rapproches. L’immunite post-vaccinale pourrait egalement etre moins efficace que l’immunite post-infectieuse, expliquant que les epidemies d’oreillons touchent plus les populations jeunes. En effet, la plupart des patients de plus de 40 ans ont ete infectes par les oreillons dans l’enfance car nes avant la generalisation de la vaccination. Enfin, la plupart des epidemies rapportees chez les vaccines semblent associees au genotype G, les anticorps vaccinaux etant plus specifiques du genotype A.

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Background Neurological complications of infective endocarditis (IE) concerns 20–40% of cases when symptomatic and 70% when asymptomatic. It is a well-identified gravity factor. Surgical indications in IE are larges and usual in emergency situations. However, neurological event, symptomatic or not, counts in surgical discussion. Sub-groups of patients with real risk of neurological deterioration during extracorporeal circulation are difficult to identify. The purpose of this study was to identify the risk factors of death and handicap in patients operated for infective endocarditis with neurological complications. Methods Retrospective monocentric study realized in CHU of Toulouse from October 2014 to March 2017. We included 78 patients treated by cardiac surgery in a context of infective endocarditis complicated by neurological event (ischemic or hemorrhagic stroke, meningitis or mycotic aneurysm). The primary endpoint was mortality and Rankins score greater than or equal to 2, at six month. Results Primary endpoint occurred in 21 patients (26%). Risk factors were anteriority of mechanical valve replacement (P = 0,004), pejorative SOFA score (P Fig. 1 ). Conclusion Main risk factors of death or handicap at six month, after a cardiac surgery in context of IE with neurological complication were hemodynamic presentation, micro organism and diabetes.

Introduction Notre objectif etait d’evaluer l’efficacite de la teicoplanine en relais de l’amoxicilline dans le traitement des endocardites infectieuses (EI) a Enterococcus faecalis (Ef). Materiels et methodes Analyse retrospective de tous les patients adultes traites pour une EI certaine a Ef dans notre etablissement entre 1997 et 2016. Les patients porteurs de materiel intra- ou extracardiaque laisse en place (hors prothese valvulaire), n’ayant pas recu de bitherapie initiale ou ayant recu de la vancomycine ont ete exclus. Les patients traites par amoxicilline (groupe 1, G1) ont ete compares a ceux pour lesquels l’amoxicilline a ete remplacee par la teicoplanine (groupe 2, G2). Resultats Soixante et onze patients ont ete inclus, 34 dans le G1 et 37 dans le G2. Les 2 groupes etaient similaires en termes d’âge (G1 67 ± 15 ans ; G2 67 ± 21 ans, p = 0,4), de comorbidites (score de Charlson, G1 : 4, IQ25–75 3–6 ; G2 : 4, IQ25–75 1–6, p = 0,6), d’EI sur prothese valvulaire (G1 12/34, 35 % ; G2 : 16/37, 43 %, p = 0,5), de taille de la vegetation (G1 : 12 mm, IQ25–75 10–18 ; G2 : 12,8 mm, IQ25–75 8,5–15, p = 0,6) et d’indication chirurgicale (G1 23/34, 68 % ; G2 : 18/37, 49 %, p = 0,1). Le G1 a presente plus d’abces perivalvulaires (9/34, 26 %) et de complications cardiaques (24/34, 71 %) que le G2 (3/37 (8 %) et 16/37 (43 %), p Conclusion Les patients ayant beneficie d’un relais par teicoplanine etaient atteints d’une EI moins grave que ceux recevant le traitement de reference. Un relais par teicoplanine pourrait representer une alternative dans le traitement des EI a Ef. Des etudes randomisees sont necessaires pour preciser la place de la teicoplanine dans cette indication, notamment chez les patients ayant des criteres de gravite et en cas d’EI sur prothese.

Copper phthalocyanine (CuPc) molecules have been deposited under ultra-high vacuum on two kinds of hydrogen-terminated silicon surfaces, namely the H–Si(1 0 0)-2 × 1 and H–Si(1 0 0)-1 × 1 surfaces. The chemical and structural properties of these interfaces were investigated in situ by X-ray photoelectron spectroscopy and X-ray photoelectron diffraction (XPD), and low-energy electron diffraction. Results from X-ray photoelectron diffraction shed light on the growth mechanism of CuPc on these two substrates. At one monolayer coverage the growth mode was characterized by the formation of crystalline 3D nano-islands. The molecular packing deduced from these studies appears very close to the one of the bulk CuPc phase. Interestingly, the growth mode appears significantly different for the two surfaces. Indeed, 3D islands are formed by molecules aligned in a standing manner in the case of H–Si(1 0 0)-2 × 1, and in a flat-lying manner in the case of H–Si(1 0 0)-1 × 1.

Malaria and HIV are two major public health issues, especially in sub-Saharan Africa. HIV infection increases the incidence of clinical malaria, inversely correlated with the degree of immunodepression. The effect of malaria on HIV infection is not as well established. Malaria, when fever and parasitemia are high, may be associated with transient increases in HIV viral load. The effect of subclinical malaria on HIV viral load is uncertain. During pregnancy, placental malaria is associated with higher plasma and placental HIV viral loads, independently of the severity of immunodeficiency. However, the clinical impact of these transient increases of HIV viral load remains unknown. Although some data suggests that malaria might enhance sexual and mother-to-child transmissions, no clinical study has confirmed this. Nevertheless pregnant women and children with malaria-induced anemia are also exposed to HIV through blood transfusions. Integrated HIV and malaria control programs in the regions where both infections overlap are necessary.

Introduction Propionibacterium acnes est une bacterie Gram positif anaerobie, commensale de la peau et de pousse longue. Les endocardites infectieuses a Propionibacterium acnes sont rares et de diagnostic difficile. Nous rapportons le cas d’une infection d’endoprothese aortique a Propionibacterium acnes mimant une fasciite. Observation Un patient de 54 ans presentait mensuellement depuis debut 2017 des myalgies des membres inferieurs febriles, cedant spontanement en un jour. Il avait comme seul antecedent une reimplantation de la valve native aortique dans une endoprothese aortique en 2014. Des hemocultures ont ete realisees au cours d’une crise, steriles. Fin mai il est hospitalise pour des myalgies hyperalgiques morphino-requerantes. Il etait apyretique et presentait uniquement un souffle d’insuffisance aortique connu et non modifie. Le bilan biologique montrait un syndrome inflammatoire avec une CRP a 100 mg/L et une hyperleucocytose. Les hemocultures etaient steriles a 5 jours. Les enzymes musculaires etaient normales. Devant la majoration des douleurs avec apparition d’une arthrite de cheville gauche febrile un scanner thoraco-abdomino-pelvien et des membres inferieurs a ete realise montrant un aspect de fasciite des membres inferieurs sans autre lesion. Une antibiotherapie par amoxicilline-acide clavulanique, clindamycine et gentamycine par voie intraveineuse a ete initiee permettant d’obtenir l’apyrexie et l’amelioration des myalgies rapide. L’echographie transoesophagienne (ETO) a revele une insuffisance aortique grade 2/4, sans vegetation. La tomographie par emission de positron (TEP-scanner) a montre des hypermetabolismes intramusculaires des membres inferieurs predominants a gauche ainsi qu’un hypermetabolisme de la prothese aortique. L’IRM musculaire a mis en evidence des plages inflammatoires avec thromboses arterielles etagees predominant sur la jambe gauche. L’IRM cerebrale etait normale. Les hemocultures sont revenues positives a Propionibacterium acnes dix jours apres leur prelevement. L’antibiotherapie a ete modifiee par amoxicilline 12 g/jour par voie intraveineuse. Le materiel a ete enleve et un Bentall realise. Les prelevements peroperatoires de la prothese poussaient a Propionibacterium acnes. La valve native etait sterile. Une antibiotherapie par amoxicilline et rifampicine a ete poursuivie pour 3 mois avec un relais par amoxicilline per os a 15 jours de la chirurgie. Avec quatre mois de suivi l’evolution est favorable sans sequelle. Discussion Les endocardites a Propionibacterium acnes sont rares, predominent chez les hommes (plus de 90 % des cas) et sont souvent des infections sur materiel (plus de 80 % des cas) survenant des annees apres la chirurgie (5 a 156 mois) avec un retard diagnostique frequent. Le temps median de positivite des hemocultures est de 7 jours. 1 , 2 , 3 . On retrouve dans la litterature une forte prevalence des complications cardiaques (volumineuses vegetations, abces). Dans notre observation, le TEP-scanner fut utile car l’ETO et le scanner injecte n’avaient pas detecte d’argument pour une infection de prothese. Selon les dernieres recommandations de l’ESC en 2015, le TEP-scanner peut etre utilise pour le diagnostic des localisations emboliques et pour etayer le diagnostic des endocardites probables selon les criteres de Duke. La presence d’emboles peripheriques est presente dans 16–17 % des endocardites a Propionibacterium acnes. De facon interessante pour l’interniste, il s’agissait chez notre patient de la presentation initiale et de la plainte principale de notre patient. Conclusion Devant une symptomatologie atypique chez un homme porteur d’une prothese endovasculaire une infection a Propionibacterium acnes doit etre evoquee avec realisation d’hemocultures a culture longue (plus de 14 jours). En cas de suspicion d’endocardite infectieuse avec une echographie cardiaque non contributive les examens de medecine nucleaire peuvent etre utiles au diagnostic.

Malaria and HIV are two major public health issues, especially in sub-Saharan Africa. The impact of HIV infection on malaria depends on the patient's immune status: immunodepression level but also immunity against Plasmodium. HIV infection increases the incidence of clinical malaria, inversely correlated with the degree of immunodepression, but the severity and mortality are increased only in areas of unstable malaria. In severe malaria the level of parasitemia is similar in HIV-positive and HIV-negative patients. During pregnancy, HIV infection increases the incidence of clinical malaria, maternal morbidity, and fetal and neonatal morbi-mortality. Sulfa-based therapies reduce the risk of malaria, most importantly in pregnancy. HIV infection increases the risk of treatment failure, mainly with sulfa-based therapies, due to re-infection or parasitic recrudescence. Further studies are needed to determine the pathophysiological interactions between HIV infection and malaria.

Radially localized electron cyclotron heating (ECH) at the 2nd harmonic (X2) is used to tailor the current profile through the modification of the temperature, and hence conductivity, profiles. The optimal conditions for current profile broadening are investigated and applied to decrease the plasma internal inductance at constant plasma current. Highly elongated plasmas are thus created at low current, where they are vertically unstable with peaked Ohmic current profiles, using active current profile broadening by far off-axis X2 ECH to ensure the vertical stability of IV the plasma. Central 3rd harmonic (X3) ECH is also applied and its impact on the current profile is described. The magnetohydrodynamic activity and in particular the replacement of the sawtooth by a multi-harmonics mode, resonant on the q = 1 surface and observed at high density and low internal inductance, is investigated.

Treatment of Scedosporium apiospermum mycetoma usually requires limb amputation. A 49-year-old woman, from Ivory Coast, was diagnosed with Madura foot in 1995. She failed to respond to several treatments including itraconazole, fluconazole and co-trimoxazole, and refused limb amputation. In December 2002 she was admitted to hospital in France with a painful, swollen right leg and foot. She had no fever and C-reactive protein was 120 mg/l. Magnetic resonance imaging (MRI) confirmed the destruction of tarsus bones with a tibia extension. Voriconazole (400 mg/day) treatment was initiated in March 2003; a significant clinical improvement was observed within 4 months as confirmed by C-reactive protein (16 mg/l) and MRI. Voriconazole was maintained for 18 months with good tolerance. Cholestasis appeared after the first month and remained stable. In October 2004 voriconazole was discontinued due to side effects on the liver (alanine aminotransferase 17 times the normal level); MRI showed impressive regression of bone lesions. As of July 2005, the patient remains clinically well. Voriconazole appears to be a promising drug for the treatment of S. apiospermum mycetomas.

American Association of Clinical Endocrinologists Medical Guidelines for Clinical Practice are systematically developed statements to assist health-care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. The presented recommendations may not be appropriate in all situations. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances. AACE Guidelines

Ohmic H-mode discharges in the Tokamak a Configuration Variable (TCV) have recently been heated for the first time by electron cyclotron (EC) waves at the 3rd harmonic (X3) at full power. New edge localized mode (ELM) behaviour has been found, with larger amplitudes at lower frequency than are typical in ohmic H-modes. This new regime required the full available X3-EC Heating (X3-ECH) power to avoid the ELM-free phase, which occurred when less heating power was applied. The energy loss per ELM can be up to 15% of the total stored energy, with values in the range 4–5% being typical of the smaller ELMs usually found in the ohmic H-mode regime. Despite these high-energy losses, the plasma temperature raises significantly in the X3 heated H-modes, doubling the stored energy from its ohmic value. The confinement time decreases when the ECH is applied, but can recover its ohmic H-mode value later in the discharge depending on the EC wave coupling. It is still not possible to provide an unambiguous classification of these ELMs as Type I.

On the TokamakConfiguration Variable (TCV), electron internal transport barriers (eITBs) can be formed during a gradual evolution from a centrally peaked to a hollow current profile while all external actuators are held constant. The formation occurs rapidly (

Electron heat transport experiments are performed in L-mode discharges at various plasma triangularities, using radially localized electron cyclotron heating to vary independently both the electron temperature T-e and the normalized electron temperature gradient R/L-Te over a large range. Local gyrofluid (GLF23) and global collisionless gyro-kinetic (LORB5) linear simulations show that, in the present experiments, trapped electron mode (TEM) is the most unstable mode. Experimentally, the electron heat diffusivity chi(e) is shown to decrease with increasing collisionality, and no dependence of chi(e) on R/L-Te is observed at high R/L-Te values. These two observations are consistent with the predictions of TEM simulations, which supports the fact that TEM plays a crucial role in electron heat transport. In addition, over the broad range of positive and negative triangularities investigated, the electron heat diffusivity is observed to decrease with decreasing plasma triangularity, leading to a strong increase of plasma confinement at negative triangularity.

In addition to the second harmonic X-mode (X2) electron cyclotron heating (ECH), the TCV ECH system has been completed with three 450 kW gyrotrons operating at the frequency of 118 GHz for third harmonic X-mode (X3) in a top-launch configuration. In the relatively low magnetic field of TCV (1.45 T), the X2 cutoff density is n(e,cutoff)((X2)) = 4 x 10(19) m(-3) and X3 extends the accessible plasma density range up to n(e,cutoff)((X3)) = 11.5 x 10(19) m(-3). The X3 absorption coefficient is lower than that for, X2 by a factor (k(B)T(e))/(m(e)c(2)) and a top-launch injection system has been installed to maximize the beam path along the resonance layer, thus maximizing the optical depth. Theoretical considerations based on a one-dimensional slab geometry model show that the X3 absorption depends mainly on the temperature and the density. It is shown, using a simple two-dimensional model, that in the presence of a suprathermal electron population, the resonance layer width is significantly increased owing to the relativistic shift. The specificity of the top-launch configuration implies that the absorption strongly depends on the propagation direction of the beam. Experimental results are compared with calculations using the linear ray-tracing code TORAY-GA. At the maximum available X3 injected power (1350M), full single-pass absorption is measured, increasing the global electron energy by a factor of 2.5, whereas TORAY-GA predicts only 50% absorption.

In the moderate magneticfield of TCV (1.5T), the recently installed X3 system (3 gyrotrons @118 GHz, 0.45 MW/each, 2s) broadens the operational space with the possibility of heating plasmas at high density, well above the cutoff density of the X2 system (X2 cutoff at ne = 4.2 × 1019m-3). To compensate the significantly weaker absorption coefficient compared to the absorption of X2, the top-launch injection allows to maximize the ray path along the resonance layer thus maximizing the optical depth. To maintain the maximum absorption in plasma discharges with a dynamic variation of both density (refraction) and temperature (relativistic shift) a real time control system on the poloidal injection angle has been developped and succesfully tested on TCV. With a total injected power of 1.35 MW and using the mirror realtime control, full-single pass absorption has been measured in an L-mode plasma. A significant fraction of the absorbed power is associated to the presence of suprathermal electrons generated by the X3 wave itself. In X3 heating experiments of H-mode plasmas it has been possible to enter into a different ELMy regime compared to the ohmic/low-power-heating ELMy regime. In these experiments a significant increase of the plasma energy is obtained with nearly fullsingle pass absorption. Results on the comparison of the absorbed fraction calculated with the TORAY-GA ray-tracing code and the beam-tracing code, ECWGB, which includes difiraction effects, are discussed.

In 1− x Ga x As layers have been grown on InP(0 0 1) substrate for x =0, 0.18, 0.75, 1. The stress supported by epilayers then evolves from compression to tension. The morphology of the growth surface was studied by scanning tunnelling microscopy, first under arsenic surface overpressure, then under cation species surface overpressure. While the former situation leads to a 2D–3D growth mode transition in the case of compression and a surface roughening in the case tension, the initial flat 2D growth mode persists at even larger deposits in the latter situation. The whole of these results could be rationalised by considering the competition between stress relaxation and surface energy. It is shown that nanostructuring of the surface by way of a 2D–3D growth transition only takes place when step edges at 2D terraces can reach a critical height. This can be realised for high compression stress and low surface energy conditions, while a high surface energy favours a continued 2D growth at both compression or tension stresses.

Current profile tailoring has been performed by application of electron cyclotron heating (ECH) and electron cyclotron current drive, leading to improved energy confinement in the plasma core of the TCV tokamak. The improved confinement is characterized by a substantial enhancement (H-factor) of the global electron energy confinement time relative to the prediction of the RLW scaling law (Rebut P H et al 1989 Proc. 12th Int. Conf. of Plasma Physics and Controlled Fusion Research (Nice, 1988) vol 2 (Vienna: IAEA) p 191), which predicts well Ohmic and standard ECH discharges on TCV. The improved confinement is attributed to a hollow current density profile producing a reversed shear profile creating an electron internal transport barrier. We relate the strength of the barrier to the depth of the hollow current density profile and the volume enclosed by the radial location of the peak current density. The rho(T)(*) (Tresset G et al 2002 Nucl. Fusion 42 520) criterion is used to evaluate the performance of the barrier relative to changes in the ECH parameters or the addition of Ohmic current, which aid in identifying the control parameters available for improving either the strength or volume of the barrier for enhanced performance. A figure of merit for the global scaling factor is used that scales the confinement enhancement as the product of the barrier volume and strength.

This paper presents experimental results on the accessibility and the properties of plasmas with improved confinement in TCV. First, the H-mode threshold power is measured in Ohmic plasmas. Above an Ohmic threshold density, the threshold power increases with the density. A lower threshold density is found when additional electron cyclotron heating (ECH) is applied. At these low densities, the threshold power increases dramatically with decreasing density. Only a small fraction of the wide operational domain leading to the Ohmic H-mode is found to lead to a stationary regime with edge localized modes (ELMs). The ELMs have an irregular frequency, but in TCV they can be triggered by an external magnetic perturbation that induces a rapid vertical movement of the plasma. With this perturbation, the ELM frequency can be increased. The ELM triggering mechanism is provided by the vertical movement of the plasma away from the X-point of a single null configuration. This movement induces a positive current at the plasma edge, and we deduce that the ELMs are being controlled by this modification of the plasma edge current.Electron internal transport barriers (eITBs) are produced deep in the plasma during the stationary phase of TCV discharges. Different scenarios of ECH or electron cyclotron current drive (ECCD) at different radial locations have been used to obtain eITBs with and without inductively driven current. The eITBs are characterized by steep electron temperature gradients, high confinement improvement and a large fraction of bootstrap current. In plasmas with fully non-inductively driven current the size and the strength of the eITB are controlled by the location of the power deposition and by the co- or counter-direction of the central ECCD. Finally, a small inductive perturbation of an otherwise non-inductively driven plasma current profile progressively shrinks the eITB, confirming the link between current profiles and eITBs.

The electron cyclotron heating (ECH) system in TCV has recently been upgraded to a total of 4.5 MW of installed power. In order to extend the density range of ECH-heated plasmas up to electron densities of 1.2 x 10(20) m(-3), three 0.5 MW gyrotrons at a frequency of 118 GHz have been added to the existing 3 MW second harmonic system operating at a frequency of 82.7 GHz. The launcher consists of a mirror placed at the top of the vessel that collects the power of the three microwave sources and can be steered radially and poloidally to ensure maximum flexibility. The choice of the top launch scheme results as a compromise between heating of high-density plasmas and maximization of single-pass absorption in Ohmically heated target plasmas. In this launching configuration, the high sensitivity of single-pass absorption to launching geometry has been experimentally demonstrated. A comparison between the experimental results and the linear ray-tracing/absorption code TORAY-GA shows a good agreement for densities up to 6.0 x 10(19) m(-3).

Plasma densities produced by half- and full-wavelength (HW and FW) helical antennae in helicon discharges are compared. It is found that HW antennae are more efficient than FW ones in producing plasma downstream from the antenna. The measured wave amplitudes and the apparent importance of downstream ionization do not agree with computations.

Diagnosis of MeV range fast ions by collective Thomson scattering (CTS) of millimetre waves was successfully demonstrated at JET. Building on the experiences from JET, a new millimetre wave based CTS fast ion diagnostic is being built for the TEXTOR tokamak. With this we intend to address both generic issues of energetic ion dynamics and specific issues for ion cyclotron resonance heating. (C) 2001 Elsevier Science B.V. All rights reserved.

Both the Pd 8 Ni 92 (110) surface and a deposit of 2 monolayers (ML) of Pd/Ni(110) have been studied by STM, LEED, and AES in order to correlate their nanoscopic structures to their catalytic properties, which were shown to be far better than those of pure Pd(110). Annealing the Pd 8 Ni 92 crystal leads to a segregation of 80% of Pd at the (110) surface layer. STM observations on Pd 8 Ni 92 show a nanostructuring of the surface that consists of chain-like structures extending mainly parallel to, or slightly tilted along, the [001] direction. Extensive annealing develops a second surface phase perfectly identifiable by [001]-oriented stripes within triangular domains. Two-dimensional alloy prepared by deposition of 2 ML of palladium on Ni(110) also exhibits chain-like reconstruction oriented along [001] very similar to the morphology from the alloy surface. In such structures atomic sites are close to the hexagonal arrangement of a Pd(111) surface but with a number of faults. These new Pd sites are supposed to be at the origin of interesting catalytic properties.

The catalytic properties, with respect to the 1,3-butadiene hydrogenation reaction, of strained Pd films on Cu(110) (lattice mismatch 8%) has been probed as a function of the film thickness. The characterization of the adlayer has been made by the combined use of STM with LEED and AES. For deposits below 1015 Pd/cm2 (i.e., about 1 ML) the catalytic activity is near zero. This is the consequence of the formation of a Pd–Cu surface alloy with tendency for Cu to migrate/segregate to the surface. The catalytic activity suddenly increases to reach a maximum value for about 3 ML; the activity is then one order of magnitude higher than that of the pure Pd(110) surface. This is the consequence of the presence of a strained Pd overlayer, with Pd surface atoms having very unusual geometry, and hence very peculiar electronic and chemical properties. The catalytic activity then decreases as the Pd coverage is increased, and tends to values near that of the pure Pd(110). Gradual relaxation of the film geometry towards that of the “normal” fcc Pd structure probably exists.

Small amounts of palladium atoms, ranging between 0.02 and 3 monolayers in thickness, were deposited onto a nickel (110) surface and studied by scanning tunneling microscopy, first in the as-deposited state and then after annealing at a temperature that allowed only surface diffusion to occur. Two different types of behavior were observed. At low submonolayer coverages palladium adatoms form elongated islands along [110] on terraces, and palladium and nickel atoms alloy within the surface layer near the steps. At higher coverages very specific chain-like nanostructures form along the [001] direction, i.e., perpendicular to the [110] direction of open rows. In the latter case, the surface morphology differs strongly from that of the initial singular (110) surface; this surface restructuring is attributed to the surface stress that develops when palladium atoms are deposited on the nickel surface. These two kinds of surface morphology can be analyzed with respect to the catalytic performance, which was tested for the 1,3-butadiene hydrogenation reaction. For low palladium deposits the reactivity is comparable to that measured for reference surfaces, such as pure Pd(110). However, the catalytic performance of palladium deposits near or above half a monolayer is improved by more than one order of magnitude. We propose to correlate such enhanced catalytic properties to the presence of very unusual surface sites created, along with the chain-like nanostructures, at strained surfaces.

Giant edge localized modes (ELMs) play an important role in the transport of plasma at the edge of tokamaks with a divertor. The loss of plasma, by mechanisms that are not well understood, causes very high power loading on parts of the wall structure. The flows of particles and energy have been determined on a rapid time-scale for the first time in JET. The soft X ray measurements have a complex structure and show a rapid onset of the instability. They prove that some plasma is lost outside the divertor and that recycling occurs to well within the separatrix. The implications of the results for the ELM instability mechanism and the design of tokamaks are discussed.

Experimental plasma-edge gradients in JET during the edge-localized-mode (ELM) free H-mode are examined for evidence of the presence and location of the transport barrier region inside the magnetic separatrix. High spatial resolution data in electron density is available in- and outside the separatrix from an Li-beam diagnostic, and in electron temperature inside the separatrix from an ECE diagnostic, while outside the separatrix, a reciprocating probe provides electron density and temperature data in the scrape-off layer. Ion temperatures and densities are measured using an edge charge-exchange diagnostic. A comparison of observed widths and gradients of this edge region with each other and with theoretical expectations is made. Measurements show that ions and electrons form different barrier regions. Furthermore, the electron temperature barrier width (3-4 cm) is about twice that of electron density, in conflict with existing scaling laws. Suitable parametrization of the edge data enables an electron pressure gradient to be deduced for the first time at JET. It rises during the ELM-free phase to reach only about half the marginal pressure gradient expected from ballooning stability before the first ELM. Subsequent type I ELMs occur on a pressure gradient contour roughly consistent with both a constant barrier width model and a ballooning mode envelope model.

The clustering development for lattice-matched Al0.48In0.52As grown on (001) oriented InP substrates by molecular beam epitaxy (MBE) has been investigated by ex-situ transmission electron microscopy (TEM) and in-situ scanning tunnelling microscopy (STM). For a growth temperature of 450°C, a V/III beam equivalent pressure (BEP) ratio equal to 20 and a growth rate of 1 μm h−1, the clusters are strongly anisotropic: typically, 2 nm along the [110] direction, 30–50 nm along the [ 1 1 ¯ 0 ] direction and 20 nm along the [001] direction. We show theoretically that such a spinodal decomposition would be forbidden if the surface of the deposited film is perfectly flat. We also demonstrate that this decomposition appears to be possible if the surface roughness is sufficient to allow a partial elastic relaxation.

The growth of compressively and tensilely strained In 1 − x Ga x As/InP(0 0 1) epilayers has been studied using the scanning tunneling microscope. For 2% compressive strain, a transition occurred after the epitaxy of five monolayers and three-dimensional islands were formed. A different type of surface roughening was observed for 2% tensile strain: three-dimensional holes were left within the terraces evolving towards the formation of chain-like surface structures. The shapes of self-assembled surface structures depend markedly on the sign of the strain imposed between mismatched materials. They can be explained by the elastic relaxation of strained unit cells, which occurs at step edges delimiting islands or holes.