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81.
In this study, historical phenotypic data from a potato breeding programme were used with an association mapping approach to identify alleles of candidate genes associated with cold‐induced sweetening of potato. Molecular marker analysis was used to determine allelic variation of candidate genes potentially involved in cold‐induced sweetening. Variations in the UDP‐glucose pyrophosphorylase (UGPase, EC 2.7.7.9) and apoplastic invertase genes (EC 3.2.1.26) were significantly associated with cold‐induced sweetening, and a possible interaction of apoplastic invertase and apoplastic invertase inhibitor was identified. This demonstrates that breeding programme phenotypic data collected over multiple years and environments can be used successfully with pedigree information for association mapping. It also confirms that the UGPase and apoplastic invertase markers are transferable across breeding programmes with distinct germplasm.  相似文献   
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An absolute environmental sustainability assessment (AESA) addresses whether a production or consumption activity can be considered environmentally sustainable in an absolute sense. This involves a comparison of its environmental pressure to its allocated environmental carrying capacity. AESA methods have been developed in multiple academic fields, each using their own set of concepts and terms with little communication across the fields. A recent growing interest in using AESA methods for decision support calls for a better common understanding of the constituents of an AESA method and how it can be communicated to scientific peers and to potential users. With this aim, we develop a framework for AESA methods, composed of a succession of four assessment steps and involving six methodological choices that must be made by the method developer or the user. We then use the framework to analyze and compare five selected AESA methods that focus on the release of phosphorus and nitrogen to the environment. In this manner, we show that the framework is able to systematically differentiate AESA methods that initially appear to be similar. Intended users of the framework include (1) method developers communicating new AESA methods to academic peers or potential method users and (2) researchers comparing a group of existing AESA methods and communicating their differences to their peers and to potential users looking for guidance on method selection.  相似文献   
84.
目的 了解3种不同抗凝人血浆检测血浆凝固酶的可行性及观察时间对结果的影响.方法 用3种不同抗凝人血浆及以不同菌液浓度作试管法凝固酶试验.结果 EDTA-K2抗凝血浆出现阳性慢,凝块大多较小,24 h内稳定性较好;枸橼酸钠抗凝血浆出现结果介于EDTA-K2、肝素抗凝血浆之间,结果最不稳定;肝素抗凝血浆出现阳性最快,但不够稳定;菌液浓度对出现阳性的早晚无影响.结论 3种抗凝人血浆在试管法凝固酶测定中使用时,出现阳性快慢不受菌液浓度影响,随时间延长溶解现象可能会增加,应掌握结果观察时间,以降低假阴性.  相似文献   
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The essay reviews John Kendrew's pioneering work on the structure of myoglobin for which he shared the Nobel Prize for Chemistry in 1962. It reconstructs the status of protein X‐ray crystallography at the time Kendrew entered the field in 1945, after distinctive service in operational research during the war. It reflects on the choice of sperm whale myoglobin as research material. In particular, it highlights Kendrew's early use of digital electronic computers for crystallographic computations and the marshaling of other tools and approaches that made it possible to solve the structure at increasing resolution. The essay further discusses the role of models in structure resolution and their broader reception. It ends by briefly reviewing Kendrew's other contributions in the formation and institutionalization of molecular biology.  相似文献   
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Das C  Frankel AD 《Biopolymers》2003,70(1):80-85
Studies of RNA-binding peptides, and recent combinatorial library experiments in particular, have demonstrated that diverse peptide sequences and structures can be used to recognize specific RNA sites. The identification of large numbers of sequences capable of binding to a particular site has provided extensive phylogenetic information used to deduce basic principles of recognition. The high frequency at which RNA-binding peptides are found in large sequence libraries suggests plausible routes to evolve sequence-specific binders, facilitating the design of new binding molecules and perhaps reflecting characteristics of natural evolution.  相似文献   
89.
Delineation of the fish family Percichthyidae (Percomorphaceae) has a long and convoluted history, with recent morphological-based studies restricting species members to South American and Australian freshwater and catadromous temperate perches. Four recent nuclear gene-based phylogenetic studies, however, found that the Percichthyidae was not monophyletic and was nested within a newly discovered inter-familial clade of Percomorphaceae, the Centrarchiformes, which comprises the Centrarchidae and 12 other families. Here, we reexamined the systematics of the Percichthyidae and Centrarchiformes based on new mitogenomic information. Our mitogenomic results are globally congruent with the recent nuclear gene-based studies although the overall amount of phylogenetic signal of the mitogenome is lower. They do not support the monophyly of the Percichthyidae, because the catadromous genus Percalates is not exclusively related to the freshwater percichthyids. The Percichthyidae (minus Percalates) and Percalates belong to a larger clade, equivalent to the Centrarchiformes, but their respective sister groups are unresolved. Because all recent analyses recover a monophyletic Centrarchiformes but with substantially different intra-relationships, we performed a simultaneous analysis for a character set combining the mitogenome and 19 nuclear genes previously published, for 22 centrarchiform taxa. This analysis furthermore indicates that the Centrarchiformes are divided into three lineages and the superfamily Cirrhitoidea is monophyletic as well as the temperate and freshwater centrarchiform perch-like fishes. It also clarifies some of the relationships within the freshwater Percichthyidae.  相似文献   
90.
Poly(sarcosine) displayed on polymeric micelle is reported to trigger a T cell‐independent type2 reaction with B1a cells in the mice to produce IgM and IgG3 antibodies. In addition to polymeric micelle, three kinds of vesicles displaying poly(sarcosine) on surface were prepared here to evaluate the amounts and avidities of IgM and IgG3, which were produced in mice, to correlate them with physical properties of the molecular assemblies. The largest amount of IgM was produced after twice administrations of a polymeric micelle of 35 nm diameter ( G1 ). On the other hand, the production amount of IgG3 became the largest after twice administrations of G3 (vesicle of 229 nm diameter) or G4 (vesicle of 85 nm diameter). The augmented avidity of IgG3 after the twice administrations compared with that at the single administration was the highest with G3 . These differences in immune responses are discussed in terms of surface density of poly(sarcosine) chains, nanoparticle size, hydrophobic component of poly(L‐lactic acid) or (Leu‐ or Val‐Aib)n, and membrane elasticity of the nanoparticles. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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