An RNA-dependent RNA polymerase which incorporates nucleotides from ribonucleoside triphosphates into an acid-insoluble polymer has been purified from the chloroplastic fraction of Chinese cabbage leaves.
1. Addition of RNA template is required for enzymatic activity; the synthetic polynucleotide poly (U, C) and TYMV-RNA are among the most active in stimulating nucleotide incorporation.
2. Poly (U,C) promotes only the incorporation of AMP and GMP. When the template is TYMV-RNA, the product is 85 % ribonuclease-resistant and the label cannot be displaced by the viral Belstaff Blouson Gangster RNA. We conclude that the synthesized RNA is complementary to the template.
3. Several properties of the enzyme have Belstaff Vetement been studied: metal ion requirement, temperature and pH effect, and Km for ribonucleotide substrate. The sedimentation coefficient of the purified enzyme is about 6 S.
4. The enzyme is found Belstaff Classic Tourist Trophy Beige in apparently healthy plants; its specific activity increases during the first week of infection by TYMV.
Moisture has for a long time been recognized as a serious contributor to premature degradation of asphaltic pavements. Many studies have been performed to collect, describe and measure the moisture susceptibility of asphaltic mixes. Most of these aimed at a comparative measure of moisture damage, either via visual observations from field data or comparative laboratory tests. The research presented in this paper is part of an ongoing research effort to move away from such comparative or empirical measures of moisture induced damage of asphaltic materials and develop a fundamental approach via a comprehensive energy based computational framework. Such a framework would enable realistic predictions and time assessment of the failure pattern occurring in an asphaltic pavement under the given environmental and traffic loading, which could be rutting, cracking, raveling or any combination or manifestation thereof. The paper discusses the fundamental moisture induced damage parameters and demonstrates the developed model.