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We have estimated the mass of metals in the molecular gas in 13 dusty star-forming galaxies at |$z \sim 4$| in which the gas, based on previous observations, lies in a cold rotating disc. We estimated the metal masses using either the submillimetre line or continuum emission from three tracers of the overall metal content – carbon atoms, carbon monoxide molecules, and dust grains – using the first simultaneous calibration of all three tracers. We obtain very similar mass estimates from the different tracers, which are similar to the entire metal content of a present-day massive early-type galaxy. We used the dynamical masses of these galaxies to estimate an upper limit on the mass of the molecular gas in each galaxy, allowing us to estimate a lower limit on the metal abundance of the gas, finding values for many of the galaxies well above the solar value. We show that the high metal masses and metal abundances are what is expected shortly after the formation of a galaxy for a top-heavy IMF. We suggest a scenario for galaxy evolution in which massive galaxies reach a high metal abundance during their formation phase, which is then gradually reduced by dry mergers with lower mass galaxies. We show that the metals in the outflows from high-redshift dusty star-forming galaxies can quantitatively explain the long-standing puzzle that such a large fraction of the metals in galaxy clusters (⁠|$\simeq$| 0.75) is in the intracluster gas rather than in the galaxies themselves. [ABSTRACT FROM AUTHOR]

The recently updated Society for Healthcare Epidemiology of America, the Infectious Diseases Society of America, and the Association of Professionals in Infection Control practice recommendations for methicillin-resistant Staphylococcus aureus (MRSA) prevention in acute care facilities list contact precautions (CPs) for patients known to be infected or colonized with MRSA as an "essential practice," meaning that it should be adopted in all acute care facilities. We argue that existing evidence on benefits and harms associated with CP do not justify this recommendation. There are no controlled trials that support broad use of CP for MRSA prevention. Data from hospitals that have discontinued CP for MRSA have found no impact on MRSA acquisition or infection. The burden and harms of CP remain concerning, including the environmental impact of increased gown and glove use. We suggest that CP be included among other "additional approaches" to MRSA prevention that can be implemented under specific circumstances (eg outbreaks, evidence of ongoing transmission despite application of essential practices). [ABSTRACT FROM AUTHOR]

Specifying annual catch limits for artisanal fisheries, low economic value stocks, or bycatch species is problematic due to data limitations. Many empirical management procedures (MPs) have been developed that provide catch advice based on achieving a stable catch or a historical target (i.e., instead of maximum sustainable yield). However, a thorough comparison of derived yield streams between empirical MPs and stock assessment models has not been explored. We first evaluate trade- offs in conservation and yield metrics for data-limited approaches through management strategy evaluation (MSE) of seven data- rich reef fish species in the Gulf of Mexico. We then apply data-limited approaches for each species and compare how catch advice differs from current age-based assessment models. MSEs identified empirical MPs (e.g., using relative abundance) as a compromise between data requirements and the ability to consistently achieve management objectives (e.g., prevent overfishing). Catch advice differed greatly among data-limited approaches and current assessments, likely due to data inputs and assumptions. Adaptive MPs become clearly viable options that can achieve management objectives while incorporating auxiliary data beyond catch-only approaches. L'etablissement de limites de prises annuelles pour les peches artisanales, les stocks de faible valeur economique ou les especes de prises accessoires pose probleme en raison des donnees limitees sur lesquelles il repose. De nombreuses procedures de gestion (PG) empiriques ont ete elaborees qui fournissent des avis sur les prises bases sur l'atteinte de prises stables ou d'une cible historique (c.-a-d. plutot que le rendement equilibre maximal). Une comparaison exhaustive des differents rendements obtenus de PG empiriques et de modeles devaluation de stock n'a toutefois pas ete effectuee. Nous evaluons d'abord les compromis touchant a la conservation et aux parametres du rendement pour des approches pour donnees limitees par revaluation des strategies de gestion (ESG) de sept especes de poissons recifaux dans le golfe du Mexique pour lesquelles les donnees sont abondantes. Nous appliquons ensuite, pour chaque espece, des approches pour des situations de donnees limitees et comparons les avis sur les prises en decoulant a ceux issus de modeles devaluation actuels bases sur l'age. Les ESG etablissent que les PG empiriques (p.ex. qui utilisent l'abondance relative) constituent un compromis entre les exigences en matiere de donnees et la capacite d'atteindre regulierement les objectifs de gestion (p.ex. la prevention de la surpeche). Les avis sur les prises different considerablement entre les approches a donnees limitees et les evaluations actuelles, vraisemblablement en raison des donnees entrees et des hypotheses sous-jacentes. Les PG adaptatives deviennent des options manifestement viables qui peuvent permettre l'atteinte des objectifs de gestion tout en incorporant des donnees auxiliaires autres que celles qui entrent dans les approches basees uniquement sur les prises. [Traduit par la Redaction], Introduction Nearly 80% of global catch comes from fisheries stocks characterized as lacking formal stock assessments, with less than 1% of species assessed using quantitative approaches due to costs and [...]

Here, we present the cloud population extracted from M51, following the application of our new high-resolution dust extinction technique to the galaxy. With this technique, we are able to image the gas content of the entire disc of M51 down to 5 pc (0.14 arcsec), which allows us to perform a statistical characterization of well-resolved molecular cloud properties across different large-scale dynamical environments and with galactocentric distance. We find that cloud growth is promoted in regions in the galaxy where shear is minimized; i.e. clouds can grow into higher masses (and surface densities) inside the spiral arms and molecular ring. We do not detect any enhancement of high-mass star formation towards regions favourable to cloud growth, indicating that massive and/or dense clouds are not the sole ingredient for high-mass star formation. We find that in the spiral arms there is a significant decline of cloud surface densities with increasing galactocentric radius, whilst in the inter-arm regions they remain relatively constant. We also find that the surface density distribution for spiral arm clouds has two distinct behaviours in the inner and outer galaxy, with average cloud surface densities at larger galactocentric radii becoming similar to inter-arm clouds. We propose that the tidal interaction between M51 and its companion (NGC 5195) – which heavily affects the nature of the spiral structure – might be the main factor behind this. [ABSTRACT FROM AUTHOR]