REPRODUCTIVE CAPACITY AND SEED SIZE IN LUPINUS TEXENSIS

The average number of ovules produced per individual of Lupinus texensis is much greater than the average number of seeds per plant. Each plant produces approximately 2,000 ovules but only 2.5% develop into seeds. One fourth of the seeds is lost due to abortion and 0.3% is lost due to predation on the plant. Mature seeds from this population exhibit a five-fold range in weight, from 10 to 56 mg. The distribution of seed weights in the field population is skewed and leptokurtic. Seed wt is positively correlated with both seed germination and seedling survivorship. Heritability of seed wt is 0.09. There is no correlation between average seed wt per plant and total number of seeds per plant, seeds per pod, or legumes per plant.     

An active role of inferior frontal cortex in conscious experience

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Release of bound immunoglobulin from SSPE brain by acid elution.

SSPE brain homogenate extracted at pH 7.4 yields immunoglobulin with a 4- to 5-fold greater hemagglutination inhibition activity per microgram of IgG than serum from the same patient. Serial washing of the homogenate results in a low level steady-state release of IgG. Elution of the washed sediment with pH 2.5, 0.1 M glycine buffer results in a 2- to 3-fold increase in recovery of hemagglutination inhibition activity with a greater hemagglutination inhibition activity per milligram of IgG than the IgG recovered by phosphate-saline extraction at pH 7.4.     

ON THE POSSIBILITY OF LYSOPHOSPHATIDE FORMATION DURING WALLERIAN DEGENERATION

—During an extensive decomposition of phospholipids, at the end of the second week of Wallerian degeneration, the decomposition of glycerophosphatides were studied in detail. In a degenerative process lasting for 2 weeks about one-third of the choline phosphatides, two-thirds of the ethanolamine phosphatides, one-third of the serine phosphatides and one-quarter of the inositol phosphatides, were destroyed. The amount of lysophosphatidylcholine decreased proportionally to the destruction of choline phosphatide. On the other hand, the amount of lysophosphatides formed from‘kephalin'-containing fatty aldehyde, during the marked destruction of these phospholipids, remained constant or increased to a small extent and its percentage distribution increased 2 or 3 times compared with other phospholipids. Ethanolamine phosphatides having a high fatty aldehyde content can be regarded as mainly responsible for the relative accumulation of lysophosphatides.     

Diaspore and gap availability are limiting species richness in wet meadows

Species pool theory claims that diaspore and microsite availability limit species richness in plant communities. Wet meadows (Calthion) and litter meadows (Molinion, Caricion davallianae) belonging to the most species-rich meadows in the foothills of the Alps have suffered from a strong decrease since the 1970s. Restoration efforts including nutrient impoverishment and rewetting management after drainage and fertilization did not result in the re-establishment of the former species richness although the abiotic filter would have been appropriate for the re-colonization of many locally extinct species. In our experiment at four sites in the largest fen of Southwest-Germany we tested if the restoration success was seed- and gap-limited. We applied sowing and hay spreading (hay seed) as treatments to make seeds available and harrowing to increase gap availability. Sowing seeds or hay seed of species of the former meadow types increased species richness immediately. The proportion of re-established species was higher when additional harrowing was applied. Species richness could be increased not only in vascular plants but also in bryophytes when hay spreading was applied. The strongest re-development towards the target communities (defined through the abiotic filter and the species richness before drainage and fertilization) took place on those sites where hay spreading and harrowing were applied. Sowing seeds and hay seed were traditional techniques to establish e.g. litter meadows, both techniques have been applied for centuries. Even harrowing was described as early as the 19th century to increase the chance of establishing certain species. Therefore, the “application of the knowledge coming from the species pool theory” (although not named during this time) has been common practice since at least the 19th century.