The authors show that the Mesoproterozoic (1.6-1.0 bn year before present) was no “boring billion” but a “bustling billion” - not only with Stromatolites and their apex in the Calymmian and Ectasian but also with the presence of multicellular organisms. To make it visible a graphical reconstruction was created. For a long time, it was assumed that there existed no noteworthy biosphere on Earth ...

1 Thimann, K. V., Ann. Rev. Biochem., 4, 545 (1935). 2 Thimann, K. V., Proc. Kon. Akad. Wetensch. Amsterdam, 38, 896 (1935); Went, F. W., and Haagen-Smit, A. J., Ibid.. 38, 852 (1935). I Kogl, F., Haagen-Smit, A. J., and Erxleben, H., Zeit. Physiol. Chem., 228, 90 (1934). 4 Lane, R. H., Am. Jour. Bot., in press. ' Thimann, K. V., Ihid., in press. 6 Snow, R., New Phytologist, 34, 347 (1935). 7 C...

Boring is an operation which converts a knot or two-component link in a 3–manifold into another knot or two-component link. It generalizes rational tangle replacement and can be described as a type of 2–handle attachment. Sutured manifold theory is used to study the existence of essential spheres and planar surfaces in the exteriors of knots and links obtained by boring a split link. It is show...

The element boron is not renowned among biologists, short of a few specialists who know that it is an essential nutrient for plants and an element in boromycin—an antibiotic compound produced by Streptomyces. Yet, on the whole, molecular biologists and, in particular, those in drug development seem to have little use for carbon’s left-hand neighbour in the periodic table. This is about to chang...

In machining industries, achieving better surface finish of a product is very essential. Surface finish is important in terms of tolerances, it reduces assembly time in mating surfaces which results in overall cost reduction. In this work, three cutting speeds, three feed rates and three depth of cuts were used in boring operation. During the boring operation, the accelerometer was fixed on the...

The objective of this study was to determine the susceptibility of the two primary direct insect pests of hazelnuts in Oregon to three species of entomopathogenic nematodes. The entomopathogenic nematodes (Heterorhabditis marelatus Pt. Reyes, Steinernema carpocapsae All and Steinernema kraussei L137) were used in laboratory soil bioassays to determine their virulence against filbertworm, Cydia ...

This study reports the genetic variations between populations of the red palm weevil, Rhynchophorus ferrugineus in the UAE area. To test if the red palm weevil population in the UAE belongs to the same genetic group; the randomly amplified polymorphic DNA (RAPD) technique was used to assay seven populations of the insect from different locations. RAPD primer pairs detected a total 216 RAPD frag...