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751.
Ashn Kunjumon V. Ramesh Kannan Yogesh T. Jasrai 《Journal of plant biochemistry and biotechnology.》1996,5(1):27-29
The regeneration potential of leaves of moth bean, pigeonpea and grass pea was studied on Murashige and Skoog’s (MS) medium supplemented with various combinations of auxins and cytokinins. Regeneration of shoots was obtained mainly on MS medium supplemented with high auxin and low cytokinin levels. However, frequency of response varied not only in the three legume species but also in their varieties studied. Roots were induced on regenerated shoots by transferring them to MS basal medium. Complete plant regeneration was observed in the three legumes in a short duration of 60–70 days. 相似文献
752.
D. Kannan 《Bulletin of mathematical biology》1983,45(3):347-400
A predator which is preying on a model-mimic system can choose either the single-trial strategy or a multi-trial strategy
as its behavior in learning to prudently harvest such a prey system. In this learning behavior, an important and often-posed
problem is to determine which among these two strategies is better suited for the predator and why one is preferable over
the other. We present in this article, using Markov chain methods, an extensive analysis of these strategies (and also of
eat-everything, strategy). We conclude that the multi-trial strategy is the one that the predator should adopt (but we will
also describe the situations when the single-trial strategy seems to be better). Our conclusions are based on the comparisons
of quantities such as the mean benefit to the predator, energy derived by a predator from the model-mimic system and (a newly
introduced notion of) contagion in eating mimics and models (these quantities are computed for different strategies). The
first two quantities are functions of the abundancep and noxiousnessb of models. The contagion is a function of onlyp; and, though independent ofb, it is also in support of multi-trial, strategy. We introduce, in the present context, a biological analog of the d'Alembert
principle and also derive functions describing the influences of eating a specified type of prey at a given time on eating
any type of prey at a later time. Various results of Estabrook-Jespersen (single-trial strategy) and Bobisud-Potratz (multi-trial
strategy) are re-derived as special cases of our more general results. A central limit theorem under the eat-everything strategy
is given. 相似文献
753.
Wei Zou Kannan Vembaiyan Milan Bhasin Dean T. Williams 《Carbohydrate research》2009,344(16):2144-2150
Highly functionalized morphan derivatives were synthesized from nitroalkene 2′-(oxoalkyl)-C-glycosides by a tandem reaction that created three (two C–N and one C–C) new bonds and four stereogenic centers in a one-pot procedure under very mild conditions without the use of expensive reagents. The transformation was achieved from a β-elimination/Michael addition cascade, followed by Michael addition of the amine and intramolecular enamination. In the presence of sodium cyanoborohydride the iminium intermediate was reduced in situ to afford the desired morphans. 相似文献
754.
Plasma insulin, pancreatic glucagon and immunoreactive glucagon-like polypeptide of intestinal origin (enteroglucagon) have been measured in 10 patients with chronic pancreatitis and 5 normal subjects. Basal levels and changes following oral glucose (50 g) and an intravenous infusion of arginine (25 g in 30 min) have been studied. In patients with chronic pancreatitis the plasma insulin response to oral glucose and intravenous arginine was reduced. Basal pancreatic glucagon was increased in the patients and increased further with oral glucose. During an arginine infusion the pancreatic glucagon showed a brisk early increase greater than that seen in the normal subjects. Basal enteroglucagon levels were significantly increased in chronic pancreatitis but response to orla glucose and arginine infusion were little different from those seen in the normal subjects. 相似文献