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21.
Summary Studies on the effect of different levels of sucrose in the slurry of peat-based Rhizobium inoculant on germination, seedling growth, and rhizosphere fungi of peanut and soybean revealed that the limits of tolerance for good germination were 2.5 and 5 per cent of the sugar, respectively. Fusaria and aspergilli were invariably present at all levels of sucrose whereas species of Penicillium, Myrothecium, Cunninghamella and Curvularia were isolated only from the rhizosphere at higher levels of the sugar 相似文献
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Several types of NS cells were identified in Portunus sanguinolentus--five types (A, A', B, C and D) in the brain and thoracic ganglion, four types (A, B, C and D) in the commissural ganglia and four types (alpha, beta, gamma and delta) in the optic ganglia. The distribution of these NS cells is described. Cytochemically, the neurosecretory material in the NS cells has a carbohydrate moiety and is rich in disulphide groups, lipids, phospholipids and RNA. It contains a small amount of sulphydryl groups and protein-bound NH2 groups, but no tyrosine or tryptophan. The NS activity of the brain was found to be closely associated with the reproductive and moult cycles. Just before the initiation of vitellogenesis and moulting the NS cells display secretory hyperactivity. Axonal transport of NS material was also observed in the NS cells. 相似文献
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Michael Jae-Yoon Chung Abram L. Friesen Dieter Fox Andrew N. Meltzoff Rajesh P. N. Rao 《PloS one》2015,10(11)
A fundamental challenge in robotics today is building robots that can learn new skills by observing humans and imitating human actions. We propose a new Bayesian approach to robotic learning by imitation inspired by the developmental hypothesis that children use self-experience to bootstrap the process of intention recognition and goal-based imitation. Our approach allows an autonomous agent to: (i) learn probabilistic models of actions through self-discovery and experience, (ii) utilize these learned models for inferring the goals of human actions, and (iii) perform goal-based imitation for robotic learning and human-robot collaboration. Such an approach allows a robot to leverage its increasing repertoire of learned behaviors to interpret increasingly complex human actions and use the inferred goals for imitation, even when the robot has very different actuators from humans. We demonstrate our approach using two different scenarios: (i) a simulated robot that learns human-like gaze following behavior, and (ii) a robot that learns to imitate human actions in a tabletop organization task. In both cases, the agent learns a probabilistic model of its own actions, and uses this model for goal inference and goal-based imitation. We also show that the robotic agent can use its probabilistic model to seek human assistance when it recognizes that its inferred actions are too uncertain, risky, or impossible to perform, thereby opening the door to human-robot collaboration. 相似文献
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Stage-dependent changes in localization of a germ cell-specific lamin during mammalian spermatogenesis 总被引:1,自引:0,他引:1
We had earlier identified a 110/120-kDa protein specific to nuclear matrix of rat pachytene spermatocytes (Behal, A., Prakash, K., and Rao, M.R.S. (1987) J. Biol. Chem. 262, 10898-10902). This protein is now shown to be a disulfide-linked homodimer of a 60-kDa polypeptide. Indirect immunofluorescence and Western blot analyses using anti-120-kDa polyclonal antibodies have shown that this protein is a component of the pore-complex lamina structure of spermatogonia. As germ cells enter meiotic prophase and the lamina structure disassembles, this polypeptide is redistributed in the nucleus and can be isolated as a component of synaptonemal complexes. Following meiotic division, this 60-kDa protein is relocalized in the lamina, then representing the sole major component of the lamina structure of round spermatids. The identity of the 60-kDa protein in the pore-complex lamina fraction and synaptonemal complexes was further confirmed by two-dimensional analysis of iodinated tryptic peptides. Such an analysis has also shown that the germ cell-specific 60-kDa protein is related but not identical to somatic lamin B. 相似文献
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Spectroscopic data and conformational energy calculations are reported for eight oligosaccharides from ovarian cyst mucins and from human milk, the nonreducing terminals of which have fucose (α1 → 2)galactose linked either (β1 → 3) (type I) or (β1 → 4)(type II) to N-acetylglucosamine or in (β1 → 3) linkage to galactosaminitol. The fully assigned proton nmr spectra are reported along with nuclear Overhauser enhancement (NOE) data. Amide proton coupling constants and vacuum-uv CD spectra provide information on the amide plane orientation and amide environment. Our results imply that the fucosidic dihedral angles are similar for all three cases and that the substantial differences in the chemical shifts of the fucosyl protons of type I, type II, and 3-ol chains result from different perturbations by the amide group of the residue to which the β-galactose is linked. Stereopair diagrams of conformational models for both type I and II H chains are presented that are consistent with NOE, coupling constants, conformational energy calculations, and the CD data. While the temperature dependence of the observed NOE of penta- and hexasaccharides indicates that their rotational correlation times are strongly temperature dependent, we conclude that the conformations are essentially independent of temperature. 相似文献
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A. Negeswara Rao 《Nordic Journal of Botany》1990,10(2):161-162
A new species of Sarcoglyphis, S. arunachalensis, from Arunachal Pradesh, India is described. 相似文献