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To produce French guidelines on Management of Liver failure in general Intensive Care Unit (ICU). A consensus committee of 23 experts from the French Society of Anesthesiology and Critical Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Association for the Study of the Liver (Association française pour l'étude du foie, AFEF) was convened. A formal conflict-of-interest (COI) policy was developed at the start of the process and enforced throughout. The entire guideline process was conducted independently of any industrial funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide their assessment of the quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. Some recommendations were ungraded. Two fields were defined: acute liver failure (ALF) and cirrhotic patients in general ICU. The panel focused on three questions with respect to ALF: (1) Which etiological examinations should be performed to reduce morbidity and mortality? (2) Which specific treatments should be initiated rapidly to reduce morbidity and mortality? (3) Which symptomatic treatment should be initiated rapidly to reduce morbidity and mortality? Seven questions concerning cirrhotic patients were addressed: (1) Which criteria should be used to guide ICU admission of cirrhotic patients in order to improve their prognosis? (2) Which specific management of kidney injury should be implemented to reduce morbidity and mortality in cirrhotic ICU patients? (3) Which specific measures to manage sepsis in order to reduce morbidity and mortality in cirrhotic ICU patients? (4) In which circumstances, human serum albumin should be administered to reduce morbidity and mortality in cirrhotic ICU patients? (5) How should digestive haemorrhage be treated in order to reduce morbidity and mortality in cirrhotic ICU patients? (6) How should haemostasis be managed in order to reduce morbidity and mortality in cirrhotic ICU patients? And (7) When should advice be obtained from an expert centre in order to reduce morbidity and mortality in cirrhotic ICU patients? Population, intervention, comparison and outcome (PICO) issues were reviewed and updated as required, and evidence profiles were generated. An analysis of the literature and recommendations was then performed in accordance with the GRADE® methodology. The SFAR/AFEF Guidelines panel produced 18 statements on liver failure in general ICU. After two rounds of debate and various amendments, a strong agreement was reached on 100% of the recommendations: six had a high level of evidence (Grade 1 ±), seven had a low level of evidence (Grade 2 ±) and six were expert judgments. Finally, no recommendation was provided with respect to one question. Substantial agreement exists among experts regarding numerous strong recommendations on the optimum care of patients with liver failure in general ICU. [ABSTRACT FROM AUTHOR]

There is a well known correlation between the mass and metallicity of star-forming galaxies. Because mass is correlated with luminosity, this relation is often exploited, when spectroscopy is not available, to estimate galaxy metallicities based on single band photometry. However, we show that galaxy color is typically more effective than luminosity as a predictor of metallicity. This is a consequence of the correlation between color and the galaxy mass-to-light ratio and the recently discovered correlation between star formation rate (SFR) and residuals from the mass-metallicity relation. Using Sloan Digital Sky Survey spectroscopy of ∼180, 000 nearby galaxies, we derive “LZC relations,” empirical relations between metallicity (in seven common strong line diagnostics), luminosity, and color (in 10 filter pairs and four methods of photometry). We show that these relations allow photometric metallicity estimates, based on luminosity and a single optical color, that are ∼50% more precise than those made based on luminosity alone; galaxy metallicity can be estimated to within ∼0.05-0.1 dex of the spectroscopically derived value depending on the diagnostic used. Including color information in photometric metallicity estimates also reduces systematic biases for populations skewed toward high or low SFR environments, as we illustrate using the host galaxy of the supernova SN 2010ay. This new tool will lend more statistical power to studies of galaxy populations, such as supernova and gamma-ray burst host environments, in ongoing and future wide-field imaging surveys. [ABSTRACT FROM AUTHOR]

Résumé: De nombreuses substances, médicamenteuses ou non, peuvent être responsables d’hépatite aiguë. Cependant, l’origine toxique, hormis lorsqu’elle est évidente, est un diagnostic d’élimination. Les causes les plus fréquentes, notamment virales, doivent être recherchées en premier. Les hépatites médicamenteuses les plus fréquentes sont dues au paracétamol, aux antibiotiques, aux antiépileptiques et aux antituberculeux. L’évaluation de la gravité de l’atteinte hépatique est primordiale. Elle repose sur des critères cliniques et biologiques. L’insuffisance hépatique aiguë est définie par une diminution du facteur V respectivement supérieur à 50 % pour les formes modérées et inférieur à 50 % pour les formes sévères. L’examen neurologique doit être minutieux à la recherche de signes d’encéphalopathie pouvant être frustes initialement. Selon la classification française, l’hépatite fulminante est définie par l’apparition d’une encéphalopathie dans les deux premières semaines ou subfulminante lorsqu’il apparaît entre la deuxième et la 12e semaine après le début de l’ictère. L’administration, même tardive, de N-acétylcystéine dans des intoxications au paracétamol avec ou sans hépatite est fondamentale. De même, dans les insuffisances hépatiques aiguës non dues au paracétamol, mais présentant une encéphalopathie grade I ou II, l’administration de N-acétylcystéine a montré une amélioration de la survie sans transplantation. Le transfert du patient vers un centre spécialisé doit être discuté devant toute hépatite toxique et doit être systématique en cas d’insuffisance hépatique associée. Il ne faut pas attendre les critères de transplantation pour transférer le patient. [ABSTRACT FROM AUTHOR]

Galaxies in the Local Group span a factor of 15 in metallicity, ranging from the super-solar M 31 to the Wolf-Lundmark-Melotte (WLM) galaxy, which is the lowest-metallicity (0.1 Zʘ) Local Group galaxy currently forming stars. Studies of massive star populations across this broad range of environments have revealed important metallicity-dependent evolutionary trends, allowing us to test the accuracy of stellar evolutionary tracks at these metallicities for the first time. The RSG population is particularly valuable as a key mass-losing phase of moderately massive stars and a source of core-collapse supernova progenitors. By reviewing recent work on the RSG populations in the Local Group, we are able to quantify limits on these stars' effective temperatures and masses and probe the relationship between RSG mass loss behaviors and host environments. Extragalactic surveys of RSGs have also revealed several unusual RSGs that display signs of unusual spectral variability and dust production, traits that may potentially also correlate with the stars' host environments. I will present some of the latest work that has advanced our understanding of RSGs in the Local Group, and consider the many new questions posed by our ever-evolving picture of these stars. [ABSTRACT FROM AUTHOR]

Levesque E, Hoti E, Azoulay D, Adam R, Samuel D, Castaing D, Saliba F. Non-invasive ICG-clearance: a useful tool for the management of hepatic artery thrombosis following liver transplantation. Clin Transplant 2011: 25: 297-301. © 2010 John Wiley & Sons A/S. The clinical presentation of hepatic artery thrombosis (HAT) post-liver transplantation (LT) varies considerably. Doppler ultrasonography (Doppler US) is the first line investigation, with a diagnostic sensitivity for HAT as high as 92%. Because indocyanine green (ICG) elimination from the blood depends among other factors on the hepatic blood flow, we hypothesized that plasma disappearance rate of indocyanine green (PDR-ICG) can be influenced by the flow in the hepatic artery. Thus, we evaluated the role of PDR-ICG measurement in HAT diagnosis in post-LT patients. Fourteen liver transplant patients with no visible flow in the hepatic artery (Doppler US) were identified. Of the 14, seven patients had HAT confirmed by CT-angiography. The PDR-ICG measurement, an investigation routinely used in our center, was performed in all 14 patients. The PDR-ICG in patients with HAT was significantly lower than in patients without HAT (5.8 ± 4.3 vs. 23.8 ± 7.4%/min, p = 0.0009). In patients with HAT, after the revascularization, the PDR-ICG value increased (5.8 ± 4.3 vs. 15.6 ± 3.5%/min, p = 0.006). The ICG elimination may be an adjunct diagnostic tool in the management of patients with suspected HAT following LT. [ABSTRACT FROM AUTHOR]

Infections remain a major cause of morbidity and mortality after liver transplantation. One possible cause of infection is preservation fluid contamination. Donor-derived pathogens, such as Candida albicans, have occasionally produced life-threatening complications in organ recipients, already described in renal transplantation. In the present case, we report the loss of a liver graft secondary to vascular complications because of C. albicans found in the preservation fluid. Our case report raises the question of implementing procedures, similar to those in renal transplantation, including early antifungal treatment and repeated radiological monitoring for the prevention and detection of vascular complications. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 67-year-old woman who was referred for an invasive squamous cell carcinoma (SCC) on her right perineum, which was operated upon. It discusses the use of Erlotinib, an epithelial growth factor receptor (EGFR) inhibitor, in the case of recurrent vulvar cancer. Use of the erlotinib was seen with rapid clinical improvement with palliation of symptoms but later on with the occurrence of Dyspnea.

Introduction Les infections fongiques à la suite de transplantations d’organes solides peuvent être associées à des complications sévères chez le receveur. Les conséquences d’une contamination du liquide de conservation (LC) par Candida spp. ont été décrites dans les suites d’une transplantation rénale avec des cas d’anévrysme de l’artère du greffon. L’objectif de cette étude était de déterminer l’incidence et les conséquences cliniques d’une contamination du LC par Candida spp. au décours d’une transplantation hépatique (TH). Matériel et méthodes Étude rétrospective incluant tous les patients transplantés hépatiques de 6 centres français de TH entre janvier 2008 et décembre 2013. Les suites post-opératoires et le devenir des receveurs après transplantation ont été colligés. Résultats Dans cette étude, 2107 patients ont été inclus et 28 avaient une contamination du LC du greffon hépatique à Candida (1,33 %). Candida albicans était le Candida le plus fréquemment retrouvé ( n = 18, 64 % des cas). Un traitement antifongique était administré chez 22 patients avec une durée de traitement allant de 7 à 37 jours. Huit patients (28,6 %) avaient développé une complication en rapport avec la contamination fongique avec des anévrysmes de l’artère hépatique ( n = 6) ou une péritonite à Candida ( n = 2). Parmi ces 8 patients, 6 avaient reçu un traitement antifongique. La mortalité a un an, des patients ayant développé une complication liée à la contamination, était de 62,5 %. Discussion L’incidence des contaminations du LC à Candida est faible en TH mais les conséquences peuvent être graves. Dans ce contexte, une surveillance angiographique de l’artère hépatique semble nécessaire dans les suites d’une TH mais devra être évaluée dans une étude à large échelle. [ABSTRACT FROM AUTHOR]

Introduction La survenue d’une candidose invasive dans les suites d’une transplantation hépatique (TH) est responsable d’une morbidité et mortalité non négligeable principalement en rapport à un retard de diagnostic. Parmi les composants de la paroi fongique, le 1,3-b- d -glucan (BDG) peut être utilisé comme un marqueur précoce de candidose invasive, et ainsi identifier les patients qui peuvent bénéficier un traitement antifongique précoce. Cette étude prospective est conduite pour évaluer la contribution du dosage de BDG dans le diagnostic de candidose invasive après TH. Matériel et méthodes Étude préliminaire monocentrique incluant tous les patients admis dans le service de réanimation dans les suites d’une TH entre janvier et juin 2013. Pour ces patients, une surveillance hebdomadaire de colonisation à candida est réalisée ainsi qu’un dosage sanguin hebdomadaire (au cours du premier mois après TH) de BDG (Fungitell ; Cape Cod Inc, États-Unis) était réalisé. De plus, le score prédictif de candidose ( Candida score) est calculé toutes les semaines. Résultats Durant la période d’étude, 52 TH ont été réalisées dans notre centre. L’âge moyen du receveur est de 55 [31–69]. Le MELD moyen du receveur est de 27 [6–40]. Les principaux motifs de la transplantation sont une cirrhose (52 %), un carcinome hépato-cellulaire (36 %). Quarante-deux patients (81 %) ont une colonisation à Candida dont le plus fréquent est le C. glabrata (55 %). Le taux de candidose invasive documentée est de 9,6 % (5/52), avec un taux de BDG > 250 pg/mL et un Candida score ≥ 4. L’aire sous la courbe ROC (Receiver Operating Characteristic) du BDG pour prédire la survenue d’une candidose invasive était de 0,93 ([95 % confidence intervalle (CI) 0,86–1,0], p = 0,001). Avec un seuil de 80 pg/mL, la sensibilité, spécificité, valeur prédictive positive (VPP) et une valeur prédictive négative du BDG pour le diagnostic de candidose invasive est respectivement de 100 %, 48 %, 17 % et 100 %. Discussion La détection dans le sérum du BDG, après transplantation hépatique, semble être un outil prometteur pour éliminer le diagnostic de candidose invasive chez les patients à haut risque. Cette étude suggère de prendre en considération un traitement antifongique préemptif chez les patients septiques ayant un Candida Score ≥ 4 et dont le dosage de BDG est > 250 pg/mL. [ABSTRACT FROM AUTHOR]

Introduction La transplantation hépatique (TH) s’accompagne d’un bon pronostic, avec une survie à 1 an de plus de 80 %. Cependant, au moment de la transplantation, les patients présentant une décompensation aiguë de leur cirrhose avec défaillances d’organe ont une mortalité péri-opératoire plus élevée. L’objectif de cette étude est d’analyser les facteurs prédictifs de futilité de la TH. Matériel et méthodes L’étude était conduite pour analyser le devenir des patients cirrhotiques transplantés hépatiques dans notre centre entre janvier 2008 et avril 2013. L’analyse était focalisée sur le devenir des patients et sur la futilité de la TH (définie par la mortalité à 1 an). L’identification de facteurs prédictifs de la futilité a été réalisée. Le niveau de décompensation (définie par le grade Acute-on-Chronic Liver Failure) était basé sur l’analyse des défaillances d’organe (Clif-SOFA) [1] . Résultats Durant la période d’étude, 309 patients cirrhotiques ont été transplantés dans notre centre d’un âge moyen était de 55 ± 9,2 ans. L’étiologie principale des cirrhoses était alcoolique (52 %) et virale (34 %). L’indication de la TH était une cirrhose ( n = 147, 47 %), ou un carcinome hépatocellulaire (CHC) sur cirrhose ( n = 142, 46 %). La mortalité globale était de 14,8 % ( n = 46). La mortalité était de 11,4 % pour l’ACLF Grade 0 vs 40 % pour les patients ACLF grade 3 ( Fig. 1 ). L’analyse statistique, comparant les patients décédés et survivants à 1 an, a montré que les scores pronostiques de gravité, évalués au moment de la TH, étaient fortement ( p < 0,01) prédictifs de la mortalité. Cependant, les valeurs de l’aire sous la courbe ROC (Receiver Operating Characteristic) prédictives de la mortalité étaient faibles de 0,47 pour le MELD, 0,59 pour le Clif-SOFA et 0,53 pour le SOFA. Discussion La mortalité post-transplantation chez les patients cirrhotiques est corrélée au grade d’ACLF au moment de la TH. Les patients présentant 3 ou plus défaillances d’organe au moment de la TH ont une mortalité largement plus élevée. Dans ce sous-groupe, une analyse à plus large échelle semble nécessaire pour déterminer les critères de futilité sachant que les différents scores pronostiques (MELD, Clif-SOFA) semblent peu fiables. [ABSTRACT FROM AUTHOR]

Passive open-top devices have been proposed as a method to experimentally increase temperature in high-latitude ecosystems. There is, however, little documentation on the efficacy of these devices. This paper examines the performance of four open-top chambers for altering temperature at six sites in the Arctic and Antarctica. Most of the heating effect was due to daytime warming above ambient; occasional night-time cooling below ambient, especially of air temperatures, depressed mean daily temperature. The mean daily temperatures at four arctic sites were generally increased by 1.2--1.8 deg.C; but occasionally, temperature depressions also occurred. Under optimal conditions at theantarctic site (dry soils, no vegetation, high radiation) mean dailysoil temperatures were increased by + 2.2 deg.C (-10 cm) to + 5.2 deg.C (0 cm). Protection from wind may play a more important role than temperature per se in providing a favourable environment for plant growth within opentop devices. Wind speed had a generally negative impact on mean daily temperature. Daily global radiation was both positively and negatively related to chamber temperature response. The effect of chambers on snow accumulation was variable with the Alexandra Fjord site showing an increased accumulation in chambers but no difference in the date of snowmelt, while at Latnjajaure in a deep snowfall site, snowmelt occurred 1--2 weeks earlier in chambers, potentially increasing the growing season. Selection of a passive temperature-enhancing system requires balancing the temperature enhancement desired against potential unwanted ecological effects such as chamber overheating and altered light, moisture, and wind. In general, the more closed the temperature-enhancing system, the higher is the temperature enhancement, but the larger are the unwanted ecological effects. Open-top chambers alter temperature significantly and minimize most unwantedecological effects; as a consequence, these chambers are a useful tool [ABSTRACT FROM AUTHOR]

Introduction L’application d’une pression expiratoire positive (PEP) est un des réglages clés de la ventilation mécanique. Son impact sur l’hémodynamique hépato-splanchnique a été largement étudié mais rarement chez les patients cirrhotiques. L’objectif de cette étude est d’évaluer l’impact d’une PEP sur les paramètres de l’hémodynamique hépato-splanchnique et sur la fonction hépatique. Patients et méthodes Étude prospective incluant les patients admis en réanimation pour décompensation aiguë d’une cirrhose et nécessitant une ventilation mécanique invasive. La fonction hépatique (bilan hépatique, clearance du vert d’indocyanine), le débit sanguin hépatique (échographie doppler hépatique) ainsi que les fonctions respiratoires (volumes pulmonaires, gazométrie artérielle) ont été évalués à deux niveaux de PEP [0 cmH 2 O (ZEP) ou 10 cmH 2 O (PEP10)]. Résultats Quarante-six patients cirrhotiques ventilés principalement pour insuffisance respiratoire aiguë ( n = 31) ou encéphalopathie hépatique ( n = 13) ont été inclus. L’âge moyen des patients était de 56,6 ± 12 ans avec un IGS II à 64 ± 21, un score de MELD à 30 ± 12 et un SOFA à 14 ± 5 à l’inclusion. La mise en place d’une PEP10 était associée à une augmentation de la PaO 2 et de la capacité résiduelle fonctionnelle (CRF) (183 ± 65 vs. 275 ± 77 mmHg, p < 0,001 ; et 812 ± 202 vs. 1079 ± 295 mL, p < 0,001). Au niveau hémodynamique, l’index cardiaque n’était pas modifié par l’augmentation de la PEP (4,3 ± 1,6 vs 4,2 ± 1,7 mL/min/m 2 ; p = 0,43). Seule la pression veineuse centrale était significativement plus élevée en PEP10 (10,0 ± 2,9 vs. 8,2 ± 2,6 mmHg, p = 0,015). Aucune modification des paramètres de la fonction hépatique ni de l’hémodynamique hépato-splanchnique n’a été observée au cours de l’étude (taux de disparition du vert d’Indocyanine 8,1 ± 4 vs 7,9 ± 3 %/min, p = 0,86). Discussion L’application d’une PEP à 10 cmH 2 O bénéficie aux patients cirrhotiques en améliorant l’oxygénation et la CRF sans dégrader l’hémodynamique (systémique et hépato-splanchnique) ainsi que la fonction hépatique. [ABSTRACT FROM AUTHOR]

Context. The post-main-sequence evolution of massive stars is very sensitive to many parameters of the stellar models. Key parameters are the mixing processes, the metallicity, the mass-loss rate, and the effect of a close companion. Aims. We study the change in the red supergiant (RSG) lifetimes, the tracks in the Hertzsprung-Russel diagram (HRD), the positions in this diagram of the pre-supernova progenitor and the structure of the stars at that time for various mass-loss rates during the RSG phase and for two different initial rotation velocities. Methods. Stellar models were computed with the Geneva code for initial masses between 9 and 25 M⊙ at solar metallicity (Z = 0.014) with 10 times and 25 times the standard mass-loss rates during the RSG phase, with and without rotation. Results. The surface abundances of RSGs are much more sensitive to rotation than to the mass-loss rates during that phase. A change of the RSG mass-loss rate has a strong impact on the RSG lifetimes and in turn on the luminosity function of RSGs. An observed RSG is associated with a model of higher initial mass when models with an enhanced RSG mass-loss rate are used to deduce that mass. At solar metallicity, models with an enhanced mass-loss rate produce significant changes in the populations of blue, yellow, and RSGs. When extended blue loops or blueward excursions are produced by enhanced mass-loss, the models predict that a majority of blue (yellow) supergiants are post-RSG objects. These post-RSG stars are predicted to show much lower surface rotational velocities than similar blue supergiants on their first crossing of the HR gap. Enhanced mass-loss rates during the RSG phase have little impact on the Wolf-Rayet populations. The position in the HRD of the end point of the evolution depends on the mass of the hydrogen envelope. More precisely, whenever at the pre-supernova stage the H-rich envelope contains more than about 5% of the initial mass, the star is a RSG, and whenever the H-rich envelope contains less than 1% of the total mass, the star is a blue supergiant. For intermediate situations, intermediate colors and effective temperatures are obtained. Yellow progenitors for core-collapse supernovae can be explained by models with an enhanced mass-loss rate, while the red progenitors are better fitted by models with the standard mass-loss rate. [ABSTRACT FROM AUTHOR]

The double explosion of SN 2009ip in 2012 raises questions about our understanding of the late stages of massive star evolution. Here we present a comprehensive study of SN 2009ip during its remarkable rebrightenings. High-cadence photometric and spectroscopic observations from the GeV to the radio band obtained from a variety of ground-based and space facilities (including the Very Large Array, Swift, Fermi, Hubble Space Telescope, and XMM) constrain SN 2009ip to be a low energy (E ∼ 1050 erg for an ejecta mass ∼0.5 M☼) and asymmetric explosion in a complex medium shaped by multiple eruptions of the restless progenitor star. Most of the energy is radiated as a result of the shock breaking out through a dense shell of material located at ∼5 × 1014 cm with M ∼ 0.1 M☼, ejected by the precursor outburst ∼40 days before the major explosion. We interpret the NIR excess of emission as signature of material located further out, the origin of which has to be connected with documented mass-loss episodes in the previous years. Our modeling predicts bright neutrino emission associated with the shock break-out if the cosmic-ray energy is comparable to the radiated energy. We connect this phenomenology with the explosive ejection of the outer layers of the massive progenitor star, which later interacted with material deposited in the surroundings by previous eruptions. Future observations will reveal if the massive luminous progenitor star survived. Irrespective of whether the explosion was terminal, SN 2009ip brought to light the existence of new channels for sustained episodic mass loss, the physical origin of which has yet to be identified. [ABSTRACT FROM AUTHOR]

We present the first spectroscopic study of the host environments of Type Ibc supernovae (SNe Ibc) discovered exclusively by untargeted SN searches. Past studies of SN Ibc host environments have been biased toward high-mass, high-metallicity galaxies by focusing on SNe discovered in galaxy-targeted SN searches. Our new observations more than double the total number of spectroscopic stellar population age and metallicity measurements published for untargeted SN Ibc host environments. For the 12 SNe Ib and 21 SNe Ic in our metallicity sample, we find median metallicities of 0.62 Z☼ and 0.83 Z☼, respectively, but determine that the discrepancy in the full distribution of metallicities is not statistically significant. This median difference would correspond to only a small difference in the mass loss via metal-line-driven winds (≲ 30%), suggesting this does not play the dominant role in distinguishing SNe Ib and Ic progenitors. However, the median metallicity of the seven broad-lined SNe Ic (SNe Ic-BL) in our sample is significantly lower, 0.45 Z☼. The age of the young stellar population of SN Ic-BL host environments also seems to be lower than for SNe Ib and Ic, but our age sample is small. Combining all SN Ibc host environment spectroscopy from the literature to date does not reveal a significant difference in SN Ib and Ic metallicities, but reinforces the significance of the lower metallicities for SNe Ic-BL. This combined sample demonstrates that galaxy-targeted SN searches introduce a significant bias for studies seeking to infer the metallicity distribution of SN progenitors, and we identify and discuss other systematic effects that play smaller roles. We discuss the path forward for making progress on SN Ibc progenitor studies in the Large Synoptic Survey Telescope era. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile. [ABSTRACT FROM AUTHOR]

Context. In recent years, many very interesting observations have appeared concerning the positions of Wolf-Rayet (WR) stars in the Hertzsprung-Russell diagram (HRD), the number ratios of WR stars, the nature of Type Ibc supernova (SN) progenitors, long and soft gamma ray bursts (LGRB), and the frequency of these various types of explosive events. These observations represent key constraints on massive star evolution. Aims. We study, in the framework of the single-star evolutionary scenario, how rotation modifies the evolution of a given initial mass star towards the WR phase and how it impacts the rates of Type Ibc SNe. We also discuss the initial conditions required to obtain collapsars and LGRB. Methods. We used a recent grid of stellar models computed with and without rotation to make predictions concerning the WR populations and the frequency of different types of core-collapse SNe. Current rotating models were checked to provide good fits to the following features: solar luminosity and radius at the solar age, main-sequence width, red-giant and red-supergiant (RSG) positions in the HRD, surface abundances, and rotational velocities. Results. Rotating stellar models predict that about half of the observed WR stars and at least half of the Type Ibc SNe may be produced through the single-star evolution channel. Rotation increases the duration of the WNL and WNC phases, while reducing those of the WNE and WC phases, as was already shown in previous works. Rotation increases the frequency of Type Ic SNe. The upper mass limit for Type II-P SNe is ∼19.0 Mϴ for the non rotating models and ∼16.8 Mϴ for the rotating ones. Both values agree with observations. Moreover, present rotating models provide a very good fit to the progenitor of SN 2008ax. We discuss future directions of research for further improving the agreement between the models and the observations. We conclude that the mass-loss rates in the WNL and RSG phases are probably underestimated at present. We show that up to an initial mass of 40 Mϴ, a surface magnetic field inferior to about 200 G may be sufficient to produce some braking. Much lower values are needed at the red supergiant stage. We suggest that the presence/absence of any magnetic braking effect may play a key role in questions regarding rotation rates of young pulsars and the evolution leading to LGRBs. [ABSTRACT FROM AUTHOR]

Long duration gamma-ray bursts are commonly associated with the deaths of massive stars. Spectroscopic studies using the afterglow as a light source provide a unique opportunity to unveil the medium surrounding it, probing the densest region of their galaxies. This material is usually in a low ionization state and at large distances from the burst site, hence representing the normal interstellar medium in the galaxy. Here we present the case of GRB 090426 at , whose optical spectrum indicates an almost fully ionized medium together with a low column density of neutral hydrogen. For the first time, we also observe variations in the Ly absorption line. Photoionization modelling shows that we are probing material from the vicinity of the burst ( pc). The host galaxy is a complex of two luminous interacting galaxies, which might suggest that this burst could have occurred in an isolated star-forming region outside its host galaxy created in the interaction of the two galaxies. [ABSTRACT FROM AUTHOR]

We present numerical simulations investigating the interaction of active galactic nucleus jets with galaxy clusters, for the first time taking into account the dynamic nature of the cluster gas and detailed cluster physics. The simulations successfully reproduce the observed morphologies of radio sources in clusters. We find that cluster inhomogeneities and large-scale flows have a significant impact on the morphology of the radio source and cannot be ignored a priori when investigating radio source dynamics. Morphological comparison suggests that the gas in the centres of clusters like Virgo and Abell 4059 shows significant shear and/or rotation. We find that shear and rotation in the intracluster medium move large amounts of cold material back into the path of the jet, ensuring that subsequent jet outbursts encounter a sufficient column density of gas to couple with the inner cluster gas, thus alleviating the problem of evacuated channels discussed in the recent literature. The same effects redistribute the excess energy Δ E deposited by the jet, making the distribution of Δ E at late times consistent with being isotropic. [ABSTRACT FROM AUTHOR]

The seasonal patterns of leaf exsertion, elongation, and senescence were described and compared for two of the most abundant graminoid species of Alaskan moist tussock tundra, Eriophorum vaginatum and Carexbigelowii. In addition the responses of both species to NPK fertilizer and to variation in site fertility (water track vs. non-track areas) were also assayed and compared. The research was done over two full growing seasons at two sites near Toolik Lake, Alaska, where other aspects of the ecology of both species have been the subject of intensive and ongoing research. Both species showed the typical graminoid pattern of sequential leaf growth, in which the exsertion and elongation of new leaves is coincident with the senescence of old leaves. However, the rates of these processes were much slower and steadier in Eriophorum than in Carex, with much greater overlap in the life histories of individual leaf cohorts. The total and green leaf lengths of whole tillers in Eriophorum were also less variable over the entire year than in Carex. The conclusion is that leaf growth in Carex shoulddepend more on external storage of carbon and nutrients than Eriophorum, with a much greater seasonal variation in demands on storage andretranslocation to and from leaves. The effects of fertilizer and the water track on leaf growth dynamics and turnover rates were largelynonsignificant, despite major effects on total tiller size and productivity. This is in contrast to previous research on evergreen leaf dynamics, but similar to results of previous research on overall production and biomass regulation in Eriophorum. It is concluded that the graminoid response to increased nutrient availability in the Arctic is to dilute the greater amounts of nutrient uptake by greater growth,so that nearly the same metabolic homeostasis is achieved as under low nutrient availability, but at a higher biomass. [ABSTRACT FROM AUTHOR]

Long duration γ-ray bursts (GRBs) mark the explosive death of some massive stars and are a rare sub-class of type Ibc supernovae. They are distinguished by the production of an energetic and collimated relativistic outflow powered by a central engine (an accreting black hole or neutron star). Observationally, this outflow is manifested in the pulse of γ-rays and a long-lived radio afterglow. Until now, central-engine-driven supernovae have been discovered exclusively through their γ-ray emission, yet it is expected that a larger population goes undetected because of limited satellite sensitivity or beaming of the collimated emission away from our line of sight. In this framework, the recovery of undetected GRBs may be possible through radio searches for type Ibc supernovae with relativistic outflows. Here we report the discovery of luminous radio emission from the seemingly ordinary type Ibc SN 2009bb, which requires a substantial relativistic outflow powered by a central engine. A comparison with our radio survey of type Ibc supernovae reveals that the fraction harbouring central engines is low, about one per cent, measured independently from, but consistent with, the inferred rate of nearby GRBs. Independently, a second mildly relativistic supernova has been reported. [ABSTRACT FROM AUTHOR]

We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB 090423 at z = 8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3σ limits of Fν(222 GHz) ≲ 33 μJy and Fν(3.6 μm) ≲ 81 nJy. The FIR limit is about 20 times fainter than the luminosity of the local ULIRG Arp 220 and comparable to the local starburst M 82. Comparing this with model spectral energy distributions, we place a limit on the infrared (IR) luminosity of LIR(8-1000 μm) ≲ 3 × 1010L☼, corresponding to a limit on the obscured star formation rate of M☼ yr–1. For comparison, the limit on the unobscured star formation rate from Hubble Space Telescope rest-frame ultraviolet (UV) observations is SFRUV ≲ 1 M☼ yr–1. We also place a limit on the host galaxy stellar mass of M* ≲ 5 × 107M☼ (for a stellar population age of 100 Myr and constant star formation rate). Finally, we compare our millimeter observations to those of field galaxies at z ≳ 4 (Lyman break galaxies, Lyα emitters, and submillimeter galaxies) and find that our limit on the FIR luminosity is the most constraining to date, although the field galaxies have much larger rest-frame UV/optical luminosities than the host of GRB 090423 by virtue of their selection techniques. We conclude that GRB host galaxies at z ≳ 4, especially those with measured interstellar medium metallicities from afterglow spectroscopy, are an attractive sample for future ALMA studies of high redshift obscured star formation. [ABSTRACT FROM AUTHOR]

Introduction et but de l’étude La transplantation hépatique (TH) est le traitement de référence des insuffisances hépatiques terminales et s’accompagne d’un bon pronostic, avec une survie à 1 an de plus de 80 %. Les patients (principalement les cirrhotiques) candidats à la TH souffrent de dénutrition responsable d’une surmorbi-mortalité. Des recommandations ont été récemment émises en termes de prise en charge nutritionnelle péri-opératoires. L’objectif de cette étude est d’évaluer les pratiques concernant la prise en charge nutritionnelle post-TH. Matériel et méthodes Étude observationnelle réalisée sur une période de 8 mois (entre janvier et août 2014) dans les services de réanimation digestive et d’hépatologie du CHU Henri Mondor, Créteil. Un suivi des apports nutritionnels et les modalités de reprise nutritionnelle des patients après TH a été réalisé au cours du séjour en réanimation et à l’hôpital. Une comparaison de nos pratiques nutritionnelles par rapport recommandations émises, exprimée en % de l’apport énergétique recommandé (AER), a été réalisée. Résultats et Analyse statistique Cinquante-trois patients ont été inclus. L’âge moyen de la cohorte est de 53,9 ± 11,2 ans, avec un sexe ratio de 2,66. Les principaux motifs de transplantation hépatique est le carcinome hépato-cellulaire, la cirrhose décompensée. L’origine de l’atteinte hépatique est principalement l’alcool ou virale. La durée médiane en réanimation est de 13,5 [4–97] jours. Le poids moyen (en kg) des patients transplantés dans notre cohorte est de 75,4 ± 16,8 pour une taille (en mètre) de 1,73 ± 0,09. L’indice de masse corporel (en kg par m2) est de 25,3 ± 5,4 avec 6 patients ayant un indice supérieur > 30. Sur les 7 premiers jours en réanimation, l’apport calorique est en moyenne de 775 kcal/jour. Les besoins énergétiques (soit 60 % de l’AER) ne sont pas couverts chez plus de 64 % (34/53) des patients à J7. Parmi les patients hospitalisés plus d’une semaine en réanimation, une corrélation entre le déficit d’AER à J7 et la durée de séjour de séjour est observée. À la sortie de réanimation, seul 6 % des patients n’a pas de dette énergétique. Après TH, le déficit nutritionnel persistait après à la sortie de l’hôpital chez 25 % des patients. Conclusion Les apports protéino énergétiques des patients transplantés hépatiques sont insuffisants durant toute la période en réanimation. Si ce déficit s’améliore en sortant de réanimation, il persiste durant toute la phase d’hospitalisation. Le déficit énergétique observé après TH et son impact probable sur la morbidité observée motive au développement de stratégie de prise en charge nutritionnelle ainsi qu’à la formation des équipes aux recommandations. [ABSTRACT FROM AUTHOR]

Introduction Les patients cirrhotiques ont un risque connu d’infection bactérienne bien supérieur aux patients non cirrhotiques. Par contre, l’existence d’une cirrhose n’est pas clairement décrite comme un facteur associé à un risque élevé de candidose invasive (CI). À partir de la base de donnée des patients de notre service, nous avons recherché si la présence d’une cirrhose était un facteur de risque de CI. Matériel et méthodes Toutes les admissions en réanimation comprises entre le 1 er janvier 2006 et le 31 décembre 2011 ont été extraites de la base de données et analysées. Une CI était définie par la présence d’une candidémie et/ou d’une candidose péritonéale. Les données démographiques, les comorbidités (cirrhose, diabète, HTA, insuffisance rénale chronique, insuffisance respiratoire chronique), la présence d’une immunosuppression, d’une suppléance d’organe (ventilation mécanique, catécholamines, épuration extra-rénale), ainsi que les autres facteurs habituels de risques associés à une CI ont été testés. Les facteurs associés à la survenue d’une CI avec un p < 0,2 en analyse univariée ont été retenus pour réaliser une analyse multivariée. Résultats Deux mille deux cent cinquante-deux admissions ont été réalisées sur la période de 6 ans. L’âge moyen était de 59 ± 18 ans. La durée médiane de séjour était de 2 jours (1–6). Le motif d’admission était dans 90 % des cas une cause médicale. La mortalité globale était de 21,2 %. L’IGS2 médian était de 40 (27–56). Une cirrhose était présente dans 21,3 % des cas ( n = 480). Cinquante-deux CI ont été diagnostiquées avec 38 candidémies et 17 candidoses péritonéales. La présence d’une cirrhose était retrouvée comme étant un facteur de risque de CI avec un OR à 3,5 (1,7–6,7) ( p < 10 −3 ). Les autres facteurs associés à la présence d’une CI sont résumés dans le Tableau 1 . Concernant les fongémies, les espèces étaient par ordre de fréquence du Candida albicans (63 %) suivi du C. glabrata (18 %), C. parapsilosis (8 %), C. tropicalis (8 %) puis C. krusei (3 %). Concernant les candidoses péritonéales, les espèces étaient C. albicans (55 %) suivi du C. glabrata (20 %) et C. parapsilosis (20 %). Sept d’entre elles correspondaient à des infections de liquide d’ascite spontanées chez des patients cirrhotiques. La mortalité des CI était de 55 % et de 74 % en cas de cirrhose. Discussion Dans notre série, la cirrhose est clairement un facteur de risque de CI. La mortalité associée à une CI chez ces patients est importante. L’introduction précoce d’un traitement par une échinocandine lorsqu’un sepsis grave n’est pas rapidement contrôlé, ainsi que le changement systématique des cathéters centraux, d’autant plus qu’il existe d’autres facteurs de risques associés, pourrait être une proposition thérapeutique chez les patients cirrhotiques. [ABSTRACT FROM AUTHOR]

We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3π survey just ∼4 days after explosion. The supernova (SN) had a peak luminosity, MR ≈ –20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is vSi ≈ 19 × 103 km s–1 at ∼40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines ∼2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of 56Ni, MNi = 0.9 M☼. Applying scaling relations to the light curve, we estimate a total ejecta mass, Mej ≈ 4.7 M☼, and total kinetic energy, EK ≈ 11 × 1051 erg. The ratio of MNi to Mej is ∼2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log (O/H)PP04 + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and ∼0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with Eγ ≲ 6 × 1048 erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E ≳ 1048 erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less-stringent constraints on a weak afterglow like that seen from XRF 060218. If this SN did not harbor a GRB, these observations challenge the importance of progenitor metallicity for the production of relativistic ejecta and suggest that other parameters also play a key role. [ABSTRACT FROM AUTHOR]

We report the discovery and detailed monitoring of X-ray emission associated with the Type IIb SN 2011dh using data from the Swift and Chandra satellites, placing it among the best-studied X-ray supernovae (SNe) to date. We further present millimeter and radio data obtained with the Submillimeter Array, the Combined Array for Research in Millimeter-wave Astronomy, and the Expanded Very Large Array during the first three weeks after explosion. Combining these observations with early optical photometry, we show that the panchromatic data set is well described by non-thermal synchrotron emission (radio/mm) with inverse Compton scattering (X-ray) of a thermal population of optical photons. In this scenario, the shock partition fractions deviate from equipartition by a factor, (εe/εB) ∼ 30. We derive the properties of the shock wave and the circumstellar environment and find a time-averaged shock velocity of and a progenitor mass-loss rate of (for an assumed wind velocity, vw = 1000 km s–1). We show that these properties are consistent with the sub-class of Type IIb SNe characterized by compact progenitors (Type cIIb) and dissimilar from those with extended progenitors (Type eIIb). Furthermore, we consider the early optical emission in the context of a cooling envelope model to estimate a progenitor radius of R* ≈ 1011 cm, in line with the expectations for a Type cIIb SN. Together, these diagnostics are difficult to reconcile with the extended radius of the putative yellow supergiant progenitor star identified in archival Hubble Space Telescope observations, unless the stellar density profile is unusual. Finally, we searched for the high-energy shock breakout pulse using X-ray and gamma-ray observations obtained during the purported explosion date range. Based on the compact radius of the progenitor, we estimate that the shock breakout pulse was detectable with current instruments but likely missed due to their limited temporal/spatial coverage. Future all-sky missions will regularly detect shock breakout emission from compact SN progenitors enabling prompt follow-up observations with sensitive multi-wavelength facilities. [ABSTRACT FROM AUTHOR]