Measurement of Pulse Wave Velocity in Fetal Descending Aorta with Dual Doppler Method: A Preliminary Study

Purpose: Pulse wave velocity (PWV) provides information regarding blood pulse pressure. This study examines the feasibility of using commercially marketed dual Doppler technology to measure PWV in the aorta of the human fetus. Methods: Thirty-two singleton pregnant women participated. Eight women (tocolysis group) were given ritodrine hydrochloride and the other 24 women (normal group) were not. The descending aorta of the fetus was depicted in the longitudinal direction. Two distant sample volumes were set and two Doppler waveforms were simultaneously obtained. The distance between the two sample volumes was divided by the time interval between the start of the two waveforms, and a PWV value was obtained. 1) Scatter diagrams for the gestational week and PWV were made, and a linear regression analysis was determined. 2) The PWV for the normal group was compared with the PWV for a group described in a previous report, one measured using ultrasonic phased-tracking. 3) The PWV values in the tocolysis group were compared with those in the normal group. Results: 1) Significant correlations between PWV and gestational weeks were not found. 2) The mean (SE) of the PWV was 2.1 (0.12) m/sec, which was similar to the PWV (2.2 (0.069) m/s) measured with ultrasonic phased-tracking. 3) The mean (SE) of the PWV (2.6 (0.25) m/s) in the tocolysis group was larger than that in the normal group (p = 0.032). Conclusions: The PWV of the descending fetal aorta can be accurately and conveniently measured with a commercially marketed ultrasound machine.

Globular Cluster Subpopulations in Early-Type Galaxies: Insights into Galaxy Formation

New and archival HST images of the globular cluster systems of 17 relatively nearby galaxies and 6 more distant galaxies have been used to establish the characteristics of GC subpopulations over a range of host galaxy morphological type from E5 to Sa. GC color/metallicity, size and luminosity distributions have been examined in the nearby galaxies and color distributions have been determined for the more distant sample. Correlations with parent galaxy properties and trends with galactocentric radius have been explored. Supplemented with Keck spectroscopy, our results are best explained by an in situ formation scenario in which both GC subpopulations formed at early times within the potential well of the protogalaxy, in multiple episodes of star formation. We have also discovered a third population of clusters, fundamentally distinct from the compact red and blue clusters common in early type galaxies.

Survival and transfer of faecal indicator organisms of wastewater effluents in receiving lake waters

Water of Lake Kallavesi, which receives wastewater effluents, is used for abstraction of drinking water, for swimming and fishing. It is also used directly for washing and drinking water, both for humans and cattle, especially in summer time. These are the reasons for the present study to follow survival and transfer of faecal indicators downstream from the wastewater treatment plant. Samples were collected in winter and summer from the bottom of the lake at deep sites. At some of the sites the vertical distribution of microbes in summer was also studied. Indicators determined were faecal coliforms, enterococci, sulphite-reducing clostridia and coliphages. The farthest point was 35km for bottom samples. All the indicators could be found in sampling sites near to the discharge point with relatively high numbers. At distant sample sites, coliphages or enterococci were the most abundant. In the winter, coliphages were found up to 18km from the discharge point. In summer, indicators survived well. The results suggest that the direct use of lake water could be considered a health risk.