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Planetesimals -- asteroids and comets -- are the building blocks of planets in protoplanetary discs and the source of dust, ice and gas in debris discs. Along with planets they comprise the left-over material after star formation that constitutes a planetary system. Planets influence the dynamics of planetesimals, sculpting the orbits of debris belts to produce asymmetries or gaps. We can constrain the architecture of planetary systems, and infer the presence of unseen planetary companions, by high spatial resolution imaging of debris discs. HD~16743 is a relatively young F-type star that hosts a bright edge-on debris disc. Based on far-infrared \textit{Herschel} observations its disc was thought to be stirred by a planetary companion. Here we present the first spatially resolved observations at near-infrared and millimetre wavelengths with \textit{HST} and ALMA, revealing the disc to be highly inclined at $87\fdg3~^{+1\fdg9}_{-2\fdg5}$ with a radial extent of 157.7$^{+2.6}_{-1.5}$~au and a FWHM of 79.4$^{+8.1}_{-7.8}$~au ($\Delta R/R = 0.5$). The vertical scale height of the disc is $0.13~\pm~0.02$, significantly greater than typically assumed unstirred value of 0.05, and could be indicative of stirring of the dust-producing planetesimals within the disc by bodies at least a few times the mass of Pluto up to 18.3~$M_{\oplus}$ in the single object limit., Comment: 12 pages, 7 figures, 4 tables, accepted for publication in MNRAS

Context. In the past decade, high contrast imaging allowed the detection and characterisation of exoplanets, brown dwarfs, and circumstellar disks. Large surveys provided new insights about the frequency and properties of massive sub-stellar companions with separations from 5 to 300 au. Aims. In this context, our study aims to detect and characterise potential exoplanets and brown dwarfs within debris disks, considering a diverse population of stars with respect to stellar age and spectral type. We present in this paper the analysis of a set of H-band images taken by the VLT/SPHERE instrument in the context of the SHARDDS survey. This survey gathers 55 main-sequence stars within 100 pc, known to host a high-infrared-excess debris disk, allowing us to potentially better understand the complex interactions between substellar companions and disks. Methods. We rely on the Auto-RSM framework to perform an in-depth analysis of the considered targets, via the computation of detection maps and contrast curves. A clustering approach is used to divide the set of targets into multiple subsets, in order to reduce the computation time by estimating a single optimal parametrisation for each considered subset. Detection maps generated with different approaches are used along with contrast curves to identify potential planetary companions. Planet detection and planet occurrence frequencies are derived from the generated contrast curves, relying on two well-known evolutionary models, namely AMES-DUSTY and AMES-COND. Finally, we study the influence of the observing conditions and observing sequence characteristics on the performance measured in terms of contrast. Results. The use of Auto-RSM allows us to reach high contrast at short separations, with a median contrast of 105 at 300 mas, for a completeness level of 95%. A new planetary characterisation algorithm, based on the RSM framework, is developed and tested successfully, showing a higher astrometric and photometric precision for faint sources compared to standard approaches. Apart from the already known companion of HD 206893 and two point-like sources around HD 114082 which are most likely background stars, we did not detect any new companion around other stars. A correlation study between achievable contrasts and parameters characterising high contrast imaging sequences highlights the importance of the Strehl ratio, wind speed at a height of 30 meters, and presence of wind-driven halo to define the quality of high contrast images. Finally, planet detection and occurrence rate maps are generated and show, for the SHARDDS survey, a high sensitivity between 10 and 100 au for substellar companions with masses >10 MJ.

Context. The nearby and young β Pictoris system hosts a well resolved disk, a directly imaged massive giant planet orbiting at ≃9 au, as well as an inner planet orbiting at ≃2.7 au, which was recently detected through radial velocity (RV). As such, it offers several unique opportunities for detailed studies of planetary system formation and early evolution. Aims. We aim to further constrain the orbital and physical properties of β Pictoris b and c using a combination of high contrast imaging, long base-line interferometry, and RV data. We also predict the closest approaches or the transit times of both planets, and we constrain the presence of additional planets in the system. Methods. We obtained six additional epochs of SPHERE data, six additional epochs of GRAVITY data, and five additional epochs of RV data. We combined these various types of data in a single Markov-chain Monte Carlo analysis to constrain the orbital parameters and masses of the two planets simultaneously. The analysis takes into account the gravitational influence of both planets on the star and hence their relative astrometry. Secondly, we used the RV and high contrast imaging data to derive the probabilities of presence of additional planets throughout the disk, and we tested the impact of absolute astrometry. Results. The orbital properties of both planets are constrained with a semi-major axis of 9.8 ± 0.4 au and 2.7 ± 0.02 au for b and c, respectively, and eccentricities of 0.09 ± 0.1 and 0.27 ± 0.07, assuming the HIPPARCOS distance. We note that despite these low fitting error bars, the eccentricity of β Pictoris c might still be over-estimated. If no prior is provided on the mass of β Pictoris b, we obtain a very low value that is inconsistent with what is derived from brightness-mass models. When we set an evolutionary model motivated prior to the mass of β Pictoris b, we find a solution in the 10–11 MJup range. Conversely, β Pictoris c’s mass is well constrained, at 7.8 ± 0.4 MJup, assuming both planets are on coplanar orbits. These values depend on the assumptions on the distance of the β Pictoris system. The absolute astrometry HIPPARCOS-Gaia data are consistent with the solutions presented here at the 2σ level, but these solutions are fully driven by the relative astrometry plus RV data. Finally, we derive unprecedented limits on the presence of additional planets in the disk. We can now exclude the presence of planets that are more massive than about 2.5 MJup closer than 3 au, and more massive than 3.5 MJup between 3 and 7.5 au. Beyond 7.5 au, we exclude the presence of planets that are more massive than 1–2 MJup. Conclusions. Combining relative astrometry and RVs allows one to precisely constrain the orbital parameters of both planets and to give lower limits to potential additional planets throughout the disk. The mass of β Pictoris c is also well constrained, while additional RV data with appropriate observing strategies are required to properly constrain the mass of β Pictoris b.

Introduction Des 2017, la pharmacie et infectiologues ont initie un travail institutionnel relatif aux modalites d’administration des anti-infectieux. Compte tenu des specificites des patients de reanimation, les reanimateurs et le pharmacien clinicien ont ete sollicites. Ce travail s’inscrit en parallele dans un projet de recherche clinique (etude BLIPIC : dosage des betalactamines chez le patient atteint de pneumopathie traite par epuration extra-renale continue au citrate). Le but de ce travail est donc d’optimiser les modalites d’administration des betalactamines afin de satisfaire au mieux les objectifs pharmacocinetiques/pharmacodynamiques tout en limitant l’emergence de resistances, en privilegiant notamment les perfusions prolongees et continues. Materiels et methodes Un groupe de travail pluridisciplinaire reanimateurs/infectiologues/pharmaciens a ete constitue : une large revue de la litterature associee a une analyse des parametres de stabilite et des dispositifs medicaux requis ont ete menees. Les donnees cliniques et pharmacocinetiques/pharmacodynamiques sont issues de Medline. Un objectif minimal de concentrations residuelles/a l’equilibre de 4 a 5 fois la concentration minimale inhibitrice a ete retenu. Les donnees concernant les concentrations maximales, les solvants, les excipients et les temperatures, issues de plusieurs bases de donnees croisees aux donnees des resumes de caracteristiques des produits et des laboratoires pharmaceutiques, ont ete prises en compte pour la fixation des parametres de stabilite. Resultats Le glucose a ete privilegie comme solvant d’administration quand la stabilite le permettait, afin de limiter les troubles ioniques. Le volume de solvant administre au patient et le cout des dispositifs medicaux ont ete limites dans la mesure du possible. Des perfusions prolongees de 4 h ont ete retenues pour l’amoxicilline, l’imipenem et le meropeneme. La piperacilline–tazobactam, le cefotaxime, la ceftazidime et le cefepime sont administres en continu. Seul l’amoxicilline–acide clavulanique est administre en bolus intermittents pour des raisons de stabilite. La dose de charge avant chaque perfusion prolongee ou continue a egalement ete protocolisee. Ces modalites ont ete validees par le groupe de travail et associees au projet institutionnel presente en Comite des anti-infectieux. Afin de faciliter l’utilisation de ces protocoles, ces derniers ont ete integres au logiciel metier de l’hopital. Une sensibilisation aupres du personnel medical et paramedical a ete effectuee (affiche dans les unites). Conclusion Ce projet est a l’origine d’une optimisation, d’une uniformisation et d’une mise a disposition des protocoles, pour l’infirmier et le medecin, des modalites d’administration des betalactamines dans l’infection la plus frequente de reanimation. Ce travail est poursuivi dans les autres contextes infectieux, en fonction des posologies et cibles de concentrations necessaires.

Introduction L’introduction de concentre de dialyse au citrate, en place de l’acetate, a permis d’ameliorer la biocompatibilite et de prevenir, en partie, la coagulation dans le dialyseur. Le but de notre etude retrospective en hemodialyse conventionnelle, est d’evaluer l’impact de l’utilisation d’un concentre citrate a 1 mmol/L comparativement au concentre acetate a 3 mmol/L sur le bilan calcique et acido-basique, l’equilibre hemodynamique, et l’adequation de la dialyse. Patients et methodes Au total, 66 patients en hemodialyse conventionnelle depuis plus de 6 mois ont ete inclus. Chaque patient etait son propre temoin. La balance calcique, le statut acido-basique, l’equilibre hemodynamique, et le Kt/V par la dialysance ionique ont ete evalues sur trois periodes de plus de 2 mois : periode 1 : dialyse a l’acetate avec [Ca 2+ ] a 1,5 ou 1,75 mmol/L ; periode 2 : dialyse au citrate avec [Ca 2+ ] a 1,5 ou 1,75 mmol/L ; periode 3 : dialyse au citrate avec [Ca 2+ ] a 1,65 ou 1,75 mmol/L. Les parametres ont ete compares entre la periode 1 versus periode 2, et periode 1 versus periode 3 ; puis en realisant une approche stratifiee selon le taux de calcium du concentre. Resultats Les calcemies pre- et post-dialytiques ainsi que les bicarbonatemies pre- et post-dialytiques sont significativement plus basses ( p Discussion La baisse des calcemies semble liee a la chute du calcium ionise dans le bain citrate ou son taux est divise par 2 par rapport au bain acetate par formation de citrate tricalcique favorisant aussi la baisse tensionnelle per-dialytique. La tendance a l’acidose peut etre en rapport avec un metabolisme hepatique insuffisant du citrate. Conclusion Ces resultats suggerent que le bain citrate en hemodialyse conventionnelle necessite des ajustements des prescriptions de calcium et de bicarbonate. Des etudes supplementaires sont necessaires afin de confirmer nos observations et d’evaluer le benefice des bains au citrate sans acetate sur la survie globale et la survenue d’evenements cardiovasculaires.

Background Pharmacists play an important role by assuring and improving the quality and safety of the medication circuit, especially through pharmaceutical approval. In our hospital, only 20% of prescriptions are analysed by pharmacists because the pharmacy service suffers from a lack of clinician pharmacists. Purpose In order to enhance our pharmaceutical validation activity, we analysed our different pharmaceutical interventions and evaluated the pharmacoeconomic impact. Material and methods A prospective study was conducted in a polyvalent medicine unit for 3 months. Every prescription was analysed by a pharmacist and its interventions were categorised into several categories (aim and type of intervention). The percentage change in prescription following our intervention was assessed and the economic outcome was estimated from the daily cost of treatment change or discontinuation. Results The total number of prescription lines analysed was 6857, with 187 interventions; 50% of interventions were effective. 54% of pharmaceutical interventions aimed at switching from the intravenous (IV) to the oral route and represented the majority of savings (1200€ of 1270€ saved). A high proportion of patients receive IV therapy although this may be inappropriate. Among all pharmacist interventions, 20% recommended a dose adjustment: 40% of them were related to adaptation to kidney function (13% were followed), 26% concerned sub-therapeutic doses (40% were followed) and 34% concerned overdoses (77% followed). 11% of pharmaceutical interventions concerned substitution proposition (acceptance of only 21%); this probably leads to therapeutic failure and could lead to undesirable events. The rest of the indications related to therapeutic duplication (8%), difference in personal treatment (4%), association had no indicated (2%) and contraindication (1%). Not many of these interventions were followed, excepted in the last two categories. Conclusion Pharmacists’ interventions appear to result in an appropriate prescription and improve the safety of drug therapies. They generate financial savings due to reduction in unnecessary therapy. In the future, we should encourage a dialogue with prescribers. Extrapolation of the results should be performed to present a real financial and medical impact of the pharmaceutical interventions and to obtain a dedicated full time clinician pharmacist. References and/or Acknowledgements Validation pharmaceutique des prescriptions hospitalieres. Presse Medicale August 2005 No conflict of interest.