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A SAW device with a multi-layered piezoelectric substrate has excellent performance due to its high Q value. A multi-layer piezoelectric substrate combined with phononic crystal structures capable of acoustic wave reflection with a very small array can achieve miniaturization and high performance. In this paper, a honeycomb-shaped phononic crystal structure based on 42°Y-X LT/SiO2/poly-Si/Si-layered substrate is proposed. The analysis of the bandgap distribution under various filling fractions was carried out using dispersion and transmission characteristics. In order to study the application of PnCs in SAW devices, one-port resonators with different reflectors were compared and analyzed. Based on the frequency response curves and Bode-Q value curves, it was found that when the HC-PnC structure is used as a reflector, it can not only improve the transmission loss of the resonator but also reduce the size of the device. [ABSTRACT FROM AUTHOR]

Purpose The oxygen reserve index (ORi[TM]) is a parameter used for the noninvasive evaluation of arterial partial pressure of oxygen (PaO.sub.2), specifically in the 100-200 mmHg range. We aimed to report on the impact of indocyanine green (ICG) on the ORi[TM]. Methods In this study, we retrospectively examined patients who underwent neurosurgery between April and July 2019 and assessed the impact of ICG on ORi[TM]. We excluded patients who did not use ICG or who were not examined for ORi[TM]. The dose and timing of ICG administration were determined by a neurosurgeon. The changes in ORi[TM] were measured for up to 30 min. Results We analyzed ten patients and found that the ORi[TM] increased to 1.00 in all of them. The median time for ORi [TM] to rise to 1.00 after ICG administration was 2 min (range 1-4). After rising to 1.00, ORi [TM] decreased and took 27 min to return to the pre-dose value. Conclusion It is important to consider the initial rapid increase and subsequent slow decrease in ORi[TM] when using ICG during surgery., Author(s): Hiroshi Kondo [sup.1], Ryuji Nakamura [sup.2], Ayako Kobatake [sup.1], Yukiko Nao [sup.1], Ken Hashimoto [sup.1], Keio Nakatani [sup.1] Author Affiliations: (1) grid.505831.a, 0000 0004 0623 2857, Department of Anesthesiology, [...]

Investigating ventricular diastolic properties is crucial for understanding the physiological cardiac functions in organisms and unraveling the pathological mechanisms of cardiovascular disorders. Ventricular stiffness, a fundamental parameter that defines ventricular diastolic functions in chordates, is typically analyzed using the end‐diastolic pressure–volume relationship (EDPVR). However, comparing ventricular stiffness accurately across chambers of varying maximum volume capacities has been a long‐standing challenge. As one of the solutions to this problem, we propose calculating a relative ventricular stiffness index by applying an exponential approximation formula to the EDPVR plot data of the relationship between ventricular pressure and values of normalized ventricular volume by the ventricular weight. This article reviews the potential, utility, and limitations of using normalized EDPVR analysis in recent studies. Herein, we measured and ranked ventricular stiffness in differently sized and shaped chambers using ex vivo ventricular pressure‐volume analysis data from four animals: Wistar rats, red‐eared slider turtles, masu salmon, and cherry salmon. Furthermore, we have discussed the mechanical effects of intracellular and extracellular viscoelastic components, Titin (Connectin) filaments, collagens, physiological sarcomere length, and other factors that govern ventricular stiffness. Our review provides insights into the comparison of ventricular stiffness in different‐sized ventricles between heterologous and homologous species, including non‐model organisms. [ABSTRACT FROM AUTHOR]