Fluoride-assisted synthesis of mullite (Al5.65 Si0.35 O9.175) nanowires

Novel silicon-deficient mullite (Al_5.65Si_0.35O_9.175) single crystal nanowires were synthesized in large quantities on mica substrates assisted by the intermediate fluoride species. The nanowires have diameters in the range 50–100 nm and typical lengths of several µm. Aligned nanowires were observed at the substrate edge. The nanowires have strong photoluminescence (PL) emission bands at 310, 397, 452 and 468 nm.

Analysis of fetal heart rate asymmetry before and after 35 weeks of gestation

In this study, we have investigated the evidence of fetal heart rate asymmetry and how the fetal heart rate asymmetry changes before and after 35 weeks of gestation. Noninvasive fetal electrocardiogram (fECG) signals from 45 pregnant women at the gestational age from16 to 41 weeks with normal single pregnancies were analysed. A nonlinear parameter called heart rate asymmetry (HRA) index that measures time asymmetry of RR interval time-series signal was used to understand the changes of HRA in early and late fetus groups. Results indicate that fetal HRA measured by Porta's Index (PI) consistently increases after 35 weeks gestation compared to foetus before 32 weeks of gestation. It might be due to significant changes of sympatho-vagal balance towards delivery with more sympathetic surge. On the other hand, Guzik's Index (GI) showed a mixed effect i.e., increases at lower lags and decreases at higher lags. Finally, fHRA could potentially help identify normal and the pathological autonomic nervous system development.