Development and characterization of silicone-based tissue phantoms for pulse oximeter performance testing.

Significance: Pulse oximeter measurements are commonly relied upon for managing patient care and thus often require human testing before they can be legally marketed. Recent clinical studies have also identified disparities in their measurement of blood oxygen saturation by race or skin pigmentation.

Aim: The development of a reliable bench-top performance test method based on tissue-simulating phantoms has the potential to facilitate pre-market assessment and the development of more accurate and equitable devices.

A retrospective characterization of pediatric facemasks marketed in the United States and implications for future designs.

Background: Device manufacturers who seek to market their pediatric facemasks in the United States (U.S.), as part of anthropometric data requirement, need to demonstrate their mask designs are expected to fit the intended user population.

Transient titin-dependent ventricular defects during development lead to adult atrial arrhythmia and impaired contractility.

Developmental causes of the most common arrhythmia, atrial fibrillation (AF), are poorly defined, with compensation potentially masking arrhythmic risk. Here, we delete 9 amino acids (Δ9) within a conserved domain of the giant protein titin's A-band in zebrafish and human-induced pluripotent stem cell-derived atrial cardiomyocytes (hiPSC-aCMs). We find that zebrafish embryos' cardiac morphology is perturbed and accompanied by reduced functional output, but ventricular function recovers within days.

Conformational Dynamics of Influenza A Virus Ribonucleoprotein Complexes during RNA Synthesis.

Viral ribonucleoproteins (vRNPs) are the cornerstones of viral proliferation, as they form the macromolecular complexes that are responsible for the transcription and replication of most single-stranded RNA viruses. The influenza A virus (IAV) polymerase catalyzes RNA synthesis within the context of vRNPs where genomic viral RNA (vRNA) is packaged by the viral nucleoprotein (NP). We used high-speed atomic force microscopy and electron microscopy to study the conformational dynamics of individual IAV recombinant RNPs (rRNPs) during RNA synthesis.

Mesenchymal Wnts are required for morphogenetic movements of calvarial osteoblasts during apical expansion.

Apical expansion of calvarial osteoblast progenitors from the cranial mesenchyme (CM) above the eye is integral to calvarial growth and enclosure of the brain. The cellular behaviors and signals underlying the morphogenetic process of calvarial expansion are unknown. Time-lapse light-sheet imaging of mouse embryos revealed calvarial progenitors intercalate in 3D in the CM above the eye, and exhibit protrusive and crawling activity more apically.