Recent coherent Doppler lidar technologies for measurements of wind vector have been dedicated toward developments of all solid-state system beyond a wavelength of 1.4 μm. The main reasons are the following; eye- safety, reliabilities, long lifetime, high overall electrical efficiencies, good thermal management, etc. Among them, Tm (Thulium) and Ho (Holumium) doped solid-state lasers operating near 2 μm have been and continue to be favored for many of the remote sensing applications.
Background
Exercise‐induced bronchoconstriction (EIB), a strong positive predictor of asthma, becomes progressively less frequent with age. Although asthma tends to become less common only in boys during adolescence, sex differences in EIB, especially in preschoolers, remain unclear. To find EIB for early diagnosis and intervention asthma, mass‐screening tests considering sex differences in preschoolers are needed. In this study, we investigated whether sex differences influence the prevalence and severity of EIB in prepubertal children aged 5–6 years.
Methods
Fifty‐one children aged 5–6 years who were attending a kindergarten in Matsuyama City, Ehime, Japan, were enrolled in this cross‐sectional study. The children underwent a 6‐minute free‐running test in 2015. The peak expiratory flow rate (PEFR) was measured before exercise and 0, 3, 10, and 20 minutes after exercise. The severity of EIB was classified according to the reduction in PEFR, measured as the difference between the postexercise PEFR and the highest pre‐exercise PEFR.
Results
Of the 51 children (23 boys and 28 girls) enrolled, the prevalence of EIB defined as three criteria: a ≥15%, ≥20%, or ≥25% decrease was 54.9% (28/51), 41.2% (21/51), and 25.5% (13/51), respectively. The prevalence of EIB defined as ≥25% decrease was significantly higher in girls than in boys (39.3% vs 8.7%, P = .013). In girls, the mean percentage change in PEFR was significantly higher 20 minutes than 10 minutes postexercise (P = .043).
Conclusions
Sex difference in the prevalence and severity of EIB should be considered when evaluating EIB, even in young, prepubertal children.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.