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221.
The nonheterocystous filamentous CyanobacteriumPlectonema boryanum strain UTEX 594 contains at least two plasmids. A small 145 kb plasmid was cloned in pBR322. It has no homology with the
bigger resident plasmid or with chromosomal DNA. A small fraction of the plasmid is present in the form of multimers or concatemers.
Copy number and hybridization patterns of the plasmid were similar under dinitrogen-fixing and non-fixing conditions. Restriction
site mapping of the plasmid was done to enable its use in the development of cyanobacterial cloning vectors. It is among the
smallest natural plasmids reported from bacteria. 相似文献
222.
Environmental stress and the relationships among allozyme heterozygosity,biomass and biomass components in jack pine (Pinus banksiana Lamb.) 总被引:1,自引:0,他引:1
The relationships among allozyme heterozygosity, biomass, and seven components of biomass were studied in fifteen open-pollinated families of jack pine grown on four soil substrates. Most of these relationships were curvilinear, and were found under sub-optimal environments. None of the eight characters showed a consistent relationship with allozyme heterozygosity on the four media. Allozyme heterozygosity (phenotype) and heterozygosity (heterosis) used in conventional breeding techniques appeared to respond similarly to environmental variation. The intensity of expression of the relationship between allozyme heterozygosity and quantitative traits may be partially under environmental control. This conclusion is consistent with previous findings on the expression of heterosis in different environments. 相似文献
223.
Manoharan Mathiselvam Venkatachalam Ramkumar Duraikkannu Loganathan Serge Pérez 《Glycoconjugate journal》2014,31(1):71-87
The linkage region constituents, 2-deoxy-2-acetamido-β-D-glucopyranose (GlcNAc) and L-asparagine (Asn) are conserved in the N-glycoproteins of all eukaryotes. Elucidation of the structure and conformation of the linkage region of glycoproteins is important to understand the presentation and dynamics of the carbohydrate chain at the protein/cell surface. Earlier crystallographic studies using monosaccharide models and analogs of N-glycoprotein linkage region have shown that the N-glycosidic torsion, ?N, is more influenced by the structural variation in the sugar part than that of the aglycon moiety. To access the influence of distal sugar as well as interglycosidic linkage (α or β) on the N-glycosidic torsion angles, cellobiosyl and maltosyl alkanamides have been synthesized and structural features of seven of these analogs have been characterized by X-ray crystallography. Comparative analysis of the seven disaccharide analogs with the reported monosaccharide analogs showed that the ?N value of cellobiosyl analogs deviate ~9° with respect to GlcβNHAc. In the case of maltosyl analogs, deviation is more than 18°. These deviations indicate that the N-glycosidic torsion is influenced by addition of distal sugar as well as with respect to inter glycosidic linkage (α or β); it is less influenced by changes occurring at the aglycon. The χ2 value of alkanamide derived from glucose, cellobiose and maltose exhibit a large range of variations (from 1.6° to ?109.9°). This large span of χ2 value suggests the greater degree of rotational freedom around C1′-C2′ bond which is restricted in GlcNAc alkanamides. The present finding explicitly proved the importance of molecular architecture in the N-glycoproteins linkage region to maintain the linearity, planarity and rigidity. These factors are necessary for N-glycan to serve role in inter- as well as intramolecular carbohydrate-protein interactions. 相似文献
224.
MapReduce has become a popular framework for Big Data applications. While MapReduce has received much praise for its scalability and efficiency, it has not been thoroughly evaluated for power consumption. Our goal with this paper is to explore the possibility of scheduling in a power-efficient manner without the need for expensive power monitors on every node. We begin by considering that no cluster is truly homogeneous with respect to energy consumption. From there we develop a MapReduce framework that can evaluate the current status of each node and dynamically react to estimated power usage. In so doing, we shift work toward more energy efficient nodes which are currently consuming less power. Our work shows that given an ideal framework configuration, certain nodes may consume only 62.3 % of the dynamic power they consumed when the same framework was configured as it would be in a traditional MapReduce implementation. 相似文献
225.
Nagalapura Ramakrishnappa Prasannakumar Vala Keshava Rao Nagendraiah Jyothi Sarikonda Saroja Ankanahalli Naranayanashetty Lokesha Govindaraju Ramkumar 《Journal of Applied Entomology》2023,147(2):105-115
Aphids, thrips, whiteflies, mealy bugs and mites could cause significant yield losses in horticultural crops. Many synthetic chemicals highly hazardous to non-target organisms and the environment are in use in their management. Botanicals are ideal for safe sustainable pest management by keeping synthetic chemical use at a minimum. We studied the insecticidal properties of three botanicals viz., Annona squamosa, Ricinus communis and Sapindus mukorossi seed extracts against sucking pests viz., aphids (Aphis gossypii and Aphis craccivora) on okra (Abelmoschus esculentus) and bittergourd (Momordica charantia), thrips (Scirtothrips dorsalis) on chilli (Capsicum frutescens), whiteflies (Bemisia tabaci) on eggplant (Solanum melongena), mealy bugs (Maconellicoccus hirsutus) on betel vine (Piper betle) and mites (Tetranychus urticae) on eggplant (Solanum melongena) under laboratory conditions. The bioassay showed that A. squamosa seed extract has potent insecticidal properties on all sucking pests, except T. urticae. Though S. mukorossi seed extract exhibited no insecticidal property, had a significant acaricidal property. A. squamosa and S. mukorossi seed extracts will therefore be additional botanicals for use in organic farming for managing the sucking pests effectively. 相似文献
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