Numbers and narratives: How qualitative methods can strengthen the science of paediatric antimicrobial stewardship

Antimicrobial and diagnostic stewardship initiatives have become increasingly important in paediatric settings. The value of qualitative approaches to conduct stewardship work in paediatric patients is being increasingly recognized. This article seeks to provide an introduction to basic elements of qualitative study designs and provide an overview of how these methods have successfully been applied to both antimicrobial and diagnostic stewardship work in paediatric patients. A multidisciplinary team of experts in paediatric infectious diseases, paediatric critical care and qualitative methods has written a perspective piece introducing readers to qualitative stewardship work in children, intended as an overview to highlight the importance of such methods and as a starting point for further work. We describe key differences between qualitative and quantitative methods, and the potential benefits of qualitative approaches. We present examples of qualitative research in five discrete topic areas of high relevance for paediatric stewardship work: provider attitudes; provider prescribing behaviours; stewardship in low-resource settings; parents\u27 perspectives on stewardship; and stewardship work focusing on select high-risk patients. Finally, we explore the opportunities for multidisciplinary academic collaboration, incorporation of innovative scientific disciplines and young investigator growth through the use of qualitative research in paediatric stewardship. Qualitative approaches can bring rich insights and critically needed new information to antimicrobial and diagnostic stewardship efforts in children. Such methods are an important tool in the armamentarium against worsening antimicrobial resistance, and a major opportunity for investigators interested in moving the needle forward for stewardship in paediatric patients

Mechanisms of Hearing Loss after Blast Injury to the Ear

Given the frequent use of improvised explosive devices (IEDs) around the world, the study of traumatic blast injuries is of increasing interest. The ear is the most common organ affected by blast injury because it is the bodyﾒs most sensitive pressure transducer. We fabricated a blast chamber to re-create blast profiles similar to that of IEDs and used it to develop a reproducible mouse model to study blast-induced hearing loss. The tympanic membrane was perforated in all mice after blast exposure and found to heal spontaneously. Micro-computed tomography demonstrated no evidence for middle ear or otic capsule injuries; however, the healed tympanic membrane was thickened. Auditory brainstem response and distortion product otoacoustic emission threshold shifts were found to be correlated with blast intensity. As well, these threshold shifts were larger than those found in control mice that underwent surgical perforation of their tympanic membranes, indicating cochlear trauma. Histological studies one week and three months after the blast demonstrated no disruption or damage to the intra-cochlear membranes. However, there was loss of outer hair cells (OHCs) within the basal turn of the cochlea and decreased spiral ganglion neurons (SGNs) and afferent nerve synapses. Using our mouse model that recapitulates human IED exposure, our results identify that the mechanisms underlying blast-induced hearing loss does not include gross membranous rupture as is commonly believed. Instead, there is both OHC and SGN loss that produce auditory dysfunction

Responses of land evapotranspiration to Earth’s greening in CMIP5 Earth System Models

International audienceSatellite-observed Earth's greening has been reproduced by the latest generation of Earth System Models (ESMs) participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Land evapotranspiration (ET) is expected to rise with increasing leaf area index (LAI, Earth's greening). The responses of ET play a key role in the land–climate interaction, but they have not been evaluated previously. Here, we assessed the responses of ET to Earth's greening in these CMIP5 ESMs. We verified a significant and positive response of ET to the modeled greening in each model. However, the responses were not comparable across the ESMs because of an inherent bias in the sensitivity of ET to LAI $(\partial {\rm{E}}{\rm{T}}/\partial {\rm{L}}{\rm{A}}{\rm{I}})$ in the models: $\partial {\rm{E}}{\rm{T}}/\partial {\rm{L}}{\rm{A}}{\rm{I}}$ is precisely and inversely proportional to the trend of LAI $(\partial {\rm{L}}{\rm{A}}{\rm{I}}/\partial t)$ across the ESMs. Constrained by this inversely proportional relationship with the satellite-observed $\partial {\rm{L}}{\rm{A}}{\rm{I}}/\partial t,$ the Earth's $\partial {\rm{E}}{\rm{T}}/\partial {\rm{\text{LAI}}}$ is 0.26 (0.21–0.34) mm d−1 per m2 m−2, equaling the independent estimates from satellite-derived reconstructions of ET and LAI. Thus, the Earth's greening-induced acceleration of ET is about 11.4 mm yr−1, accounting for more than 50% of the observed increase in land ET over the last 30 years. To better model the land–climate interaction, $\partial {\rm{E}}{\rm{T}}/\partial {\rm{L}}{\rm{A}}{\rm{I}}$ in these ESMs should be calibrated. A feasible means is to improve the representation of the magnitude of LAI in these CMIP5 ESMs

Regional air pollution brightening reverses the greenhouse gases induced warming-elevation relationship

International audienc