Effect of doxapram on the electrical activity of the diaphragm waveform pattern of preterm infants

[Objective] This study aimed to evaluate the change in the waveform pattern of the electrical activity of the diaphragm (Edi) following the administration of doxapram in extremely preterm infants ventilated with neurally adjusted ventilatory assist (NAVA). [Study Design] We conducted this retrospective cohort study in our neonatal intensive care unit between November 2019 and September 2021. The study participants were extremely preterm infants under the gestational age of 28 weeks who were ventilated with NAVA and administered doxapram. We collected the data of the Edi waveform pattern and calculated the proportion. To analyze the change in the proportion of the Edi waveform pattern, we compared the proportion of the data for 1 h before and after doxapram administration. [Results] Ten extremely preterm infants were included. Almost all the patients’ respiratory condition improved after doxapram administration. The ventilatory parameters—Edi peak, Edi minimum, peak inspiratory pressure, time in backup ventilation, and number of switches to backup ventilation—did not change significantly. However, the proportion of phasic pattern significantly increased (before: 46% vs. after: 72%; p < 0.05), whereas the central apnea pattern significantly decreased after doxapram administration (before: 31% vs. after: 8.3%; p < 0.05). The proportion of irregular low-voltage patterns tended to decrease, albeit with no significant changes. [Conclusion] Our results indicated that the proportion of Edi waveform patterns changed following doxapram administration. Edi waveform pattern analysis could be a sensitive indicator of effect with other intervention for respiratory conditions

Deformation and improvement for the IR transmission of single-crystal silicon by direct current heating

We confirmed that the deformation occurred at about 800 °C when CZ-Si was pressure and heat treated by a pulse-heating method, spark plasma sintering (SPS), while at the same time, the absorption peak of silicon single crystal produced using the Czochralski process (CZ-Si), which was a major issue for infrared transparent material in the vicinity of 9 μm, was also confirmed to have been reduced within a short time. The absorption coefficient in the vicinity of 9 μm, which was derived from the interstitial oxygen, decreased the most at 800 °C, and the absorption derived from the stretching mode of Si–O observed inthe vicinity of 9.7 μm reached its maximum at 800 °C. This is considered to have been due to the migration of interstitial oxygen via clusters to change the material into amorphous SiO2. It was confirmed that the impact of the applied pressure direction was relative to crystal orientation on the peak of 9 μm. It was also found that the deformation was the maximum from the (110) plane, that the change in absorption coefficients before and after deformation was the largest, and that the relationship turned out to be (110)&gt; (100)&gt; (111). The dislocation lines in the sample after the deformation of the (100) plane were observed using EBSD, and the polarization dependencies of transmittance in the infrared region were measured for the planes parallel and perpendicular to the applied pressure