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Nanomaterials are integrated within consumer products to enhance specific properties of interest. Their release throughout the lifecycle of nano-enabled products raises concerns; specifically, mechanical strains can lead to the generation of fragmented materials containing nanomaterials. We investigated the potential release of single-walled carbon nanotubes (SWCNTs-brand TUBALL™) from epoxy composite materials. A pin-on-disk-type tribometer was used for the accelerated mechanical aging of the nanocomposites. A pristine nanocomposite material, abraded material and debris obtained from the abrasion in the tribometer were analyzed by Raman spectroscopy. The airborne-produced particles were captured using particle collectors. Stat Peel's Identifier C2 system was used to monitor the SWCNT content of respirable particles produced during the abrasion test. The SWCNT amounts found were below the LoQ. The Raman spectra conducted on the Stat Peel filters helped identify the presence of free SWCNTs released from the epoxy matrix, although they were notably scarce. Raman spectroscopy has been proved to be a crucial technique for the identification, characterization and assessment of structural changes and degradation in SWCNTs that occurred during the abrasion experiments.

The detection of starlight from the host galaxies of quasars during the reionization epoch (z > 6) has been elusive, even with deep Hubble Space Telescope observations 1,2 . The current highest redshift quasar host detected 3 , at z = 4.5, required the magnifying effect of a foreground lensing galaxy. Low-luminosity quasars 4-6 from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) 7 mitigate the challenge of detecting their underlying, previously undetected host galaxies. Here we report rest-frame optical images and spectroscopy of two HSC-SSP quasars at z > 6 with the JWST. Using near-infrared camera imaging at 3.6 and 1.5 μm and subtracting the light from the unresolved quasars, we find that the host galaxies are massive (stellar masses of 13 × and 3.4 × 10 10  M ☉ , respectively), compact and disc-like. Near-infrared spectroscopy at medium resolution shows stellar absorption lines in the more massive quasar, confirming the detection of the host. Velocity-broadened gas in the vicinity of these quasars enables measurements of their black hole masses (1.4 × 10 9 and 2.0 × 10 8  M ☉ , respectively). Their location in the black hole mass-stellar mass plane is consistent with the distribution at low redshift, suggesting that the relation between black holes and their host galaxies was already in place less than a billion years after the Big Bang., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Pediatric nurses and physicians are rarely exposed to life-threatening events. Understanding the needs of clinicians is key for designing continuing training programs. A survey exploring preparedness to manage life-threatening events as well as training needs was mailed to all clinically active nurses and physicians at a tertiary-level referral children's hospital. Overall, 469 participants out of 871 answered the questionnaire (54% response rate). Respondents felt well or very well (nurses 93%, physicians 74%) prepared to recognize a deteriorating child and rated their theoretical understanding (70% well or very well prepared) of how to manage life-threatening situations significantly higher ( p < 0.0001) than their cardiopulmonary resuscitation (CPR) preparedness (52% well or very well prepared). Both perceived theoretical understanding ( p < 0.0001) and CPR preparedness ( p < 0.002) were rated higher among nurses than physicians. Arrhythmias, shock, cardiac arrest and airway management constitute main areas of perceived training need. In conclusion, although a majority of pediatric nurses and physicians felt sufficiently trained to recognize a deteriorating child, their perceived ability to actively manage life-threatening events was inferior to their theoretical understanding of how to resuscitate a child. A high degree of institutional confidence and identification of areas of training need provide a good foundation for customizing future continuing education programs.