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OBJECTIVE: To investigate the perspectives of pediatric otolaryngologists on the impact of the coronavirus disease 2019 (COVID-19) pandemic on their research. METHODS: Two surveys were sent to members of the American Society of Pediatric Otolaryngology (ASPO) in 2019 and 2021 to assess research perspectives before and during the COVID-19 pandemic. The surveys contained questions about research engagement, barriers, time allocation, and shifts in research focus. RESULTS: The COVID-19 pandemic reshaped research within pediatric otolaryngology, with a mixed impact on the amount of time allocated to research endeavors. Almost half of respondents reported a change in research focus to COVID-19-related studies. Protected time and funding were significant pre-pandemic barriers, whereas reduced staff, collaboration opportunities, and enrollment limitations emerged as key pandemic-related obstacles. A personal commitment to research was most strongly correlated with time spent on this endeavor. During the pandemic, women were less likely to report an increase in research activity when compared to men, possibly due to a disproportionate burden of caregiving on women during school closures and stay-at-home orders. CONCLUSION: Overall, the pandemic prompted both increases and decreases in research time allocation, depending on individual circumstances and priorities. Despite new challenges, pediatric otolaryngologists remain committed to research and have continued to remain productive.
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Elevated levels of inorganic phosphate (P(i)) are believed to inhibit muscular force by reversing myosin's force-generating step. These same levels of P(i) can also affect muscle velocity, but the molecular basis underlying these effects remains unclear. We directly examined the effect of P(i) (30 mM) on skeletal muscle myosin's ability to translocate actin (V(actin)) in an in vitro motility assay. Manipulation of the pH enabled us to probe rebinding of P(i) to myosin's ADP-bound state, while changing the ATP concentration probed rebinding to the rigor state. Surprisingly, the addition of P(i) significantly increased V(actin) at both pH 6.8 and 6.5, causing a doubling of V(actin) at pH 6.5. To probe the mechanisms underlying this increase in speed, we repeated these experiments while varying the ATP concentration. At pH 7.4, the effects of P(i) were highly ATP dependent, with P(i) slowing V(actin) at low ATP (<500 µM), but with a minor increase at 2 mM ATP. The P(i)-induced slowing of V(actin), evident at low ATP (pH 7.4), was minimized at pH 6.8 and completely reversed at pH 6.5. These data were accurately fit with a simple detachment-limited kinetic model of motility that incorporated a P(i)-induced prolongation of the rigor state, which accounted for the slowing of V(actin) at low ATP, and a P(i)-induced detachment from a strongly bound post-power-stroke state, which accounted for the increase in V(actin) at high ATP. These findings suggest that P(i) differentially affects myosin function: enhancing velocity, if it rebinds to the ADP-bound state, while slowing velocity, if it binds to the rigor state.