Mean Wet Mass Research Articles

PHENOLOGY OF THE EUROPEAN CORN BORER (OSTRINIA NUBILALIS) IN ALBERTA

AbstractDifferences in phenology were observed between two populations ofOstrinia nubilalis(Hbn.) in Alberta. In the South Saskatchewan River valley, borers pupated and emerged 3–6 days earlier than on the plains. This was not simply a function of different microclimates because median pupation occurred at 331 degree-days (DD) for plains populations and at 490 DD for valley populations. First-generation flight extended from the last week in June until the 1st week in August. Flight peaks in 1983 occurred on 8 July in the valley and on 14 July on the plains. Flight was delayed in 1984 by cold nightly temperatures. In 1983 valley populations had a partial second generation, with a flight peak in late August. Mean pupal mass was significantly less for plains populations than valley populations. Transplant experiments demonstrated that these differences reflected mainly environmental influences. During spring 1984, mean larval mass in the two populations did not differ until early June, when both mean wet and dry mass of valley larvae increased significantly but those of plains larvae did not change. This variability of phenotypes contributes to the colonizing ability of the European corn borer.

Quantitative study of mitochondria in rat liver. Dry mass, wet mass, volume, and concentration of solids.

The dry mass, wet mass, and volume of mitochondria of normal rat liver were determined, as well as nitrogen content and concentration. A scheme of multiple approaches to these quantities was devised, permitting comparison of values obtained by independent methods. The following basic values are considered highly accurate: Mean dry mass, 13.6 x 10(-14) g; mean wet mass, 51.8 x 10(-14) g; mean volume, 0.43 micro(3); nitrogen content, 1.75 x 10(-14) g The work emphasizes the fact that in mitochondria the quantities, mass, and volume occur in logarithmic-normal distributions.