The halogen gas inside a halogen lamp causes the evaporated tungsten to redeposit on the filament. This process, along with high pressure inside the capsule, slows down deterioration of the filament, improves lumen maintenance and extends the lampâs service life.
The mean heart rate as obtained in this study (246 beats min â1, with a range of 207â314 beats min â1) is within the range given by several authors in chicken embryos. In a previous study () we reported heart rate values ranging between 250 and 270 beats min â1 on days 19 and 20 of incubation.
The human heart begins beating at a rate near the motherâs, about 75-80 beats per minute (BPM). The embryonic heart rate (EHR) then accelerates linearly for the first month of beating, peaking at 165-185 BPM during the early 7th week, (early 9th week after the LMP). This acceleration is approximately 3.3 BPM per day, or about 10 BPM every three days, an increase of 100 BPM in the first month.