Phospholipid turnover rates suggest that bacterial community growth rates in the open ocean are systematically underestimated

Maximum rates of climate change are systematically underestimated in the geological record

Recently observed rates of environmental change are typically much higher than those inferred for the geological past. At the same time, the magnitudes of ancient changes were often substantially greater than those established in recent history. The most pertinent disparity, however, between recent and geological rates is the timespan over which the rates are measured, which typically differ by...

Are Abnormal Yolk Sac Characteristics Important Factors in Abortion Rates?

Measurement of bacterial growth rates in soil

Measurements of the average growth rates of soil bacteria from a soil under three treatments; a conventional high input corn soybean rotation, a reversion to a native successional community (4 years) and a never ploughed grassland, were made by two methods. The specific rates of synthesis of bacterial DNA were determined from the specific activities of the DNA precursor, deoxythymidine triphosp...

Pigment-specific rates of phytoplankton growth and microzooplankton grazing in the open subarctic Pacific Ocean

A long-standing hypothesis states that low year-round phytoplankton biomass in the open subarctic Pacific Ocean is maintained by herbivorous grazing. To evaluate the balance between phytoplankton growth and microzooplankton grazing, we carried out seawater dilution experiments at two subarctic Pacific locations in June and September 1987. Pigment-specific phytoplankton growth and grazing rates ...

Dopamine receptor turnover rates in rat striatum are age-dependent.

The time course of recovery of [3H]spiperone binding in the rat striatum after a single injection of the irreversible antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) shows that a slower rate of regeneration/turnover of D-2 dopamine receptors occurs in mid-life-mature versus young male rats. This slower receptor recovery reflects relatively slower rates of both receptor synthesi...