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141.
Leaf rust caused by Puccinia triticina is an economically-important disease in wheat worldwide.A combination of different types of resistance genes may significantly enhance rust resistance under rust-favorable conditions.To investigate the interactions between the rust resistance gene Lr34 and the lesion mimic gene lm on 1BL in Ning 7840,a segregating F8-10 population of 180 recombinant inbred lines was developed from Ning 7840/Chokwang and evaluated for both lesion mimic expression and leaf rust response at the adult plant stage in a greenhouse.A major quantitative trait locus(QTL),derived from Sumai 3,was co-localized with Lr34 on chromosome 7D and explained 41.5% of phenotypic variations for rust severity and 22.1% for leaf tip necrosis(LTN).The presence of Lr34 was confirmed by Lr34-specific markers cssfr1 and cssfr2 in Ning 7840 and Sumai 3.Unlike Lr34,lm conditioned a spontaneous lesion mimic phenotype and had a significant effect on reducing uredinial size,and a smaller effect on severity.Additive effects were observed between lm and Lr34 for severity and LTN,and an epistatic effect was observed for infection type.Single marker analysis also identified several other QTL with minor effects on severity,infection type,or LTN. 相似文献
142.
143.
The abundant entities and entity-attribute relations in medical websites are important data resources for medical research. However, the medical websites are usually characterized of storing entity and attribute values in different pages. To extract those data records efficiently, we propose an automatic extraction system which is related to entity and attribute relations (attributes and values) of separate storage. Our system includes following modules: (1) rich-information interactive annotation page rendering; (2) separate storage attribute relations annotating; (3) annotated relations for pattern generating and data records extracting. This paper presents the relations about the attributes which are stored in many pages by effective annotation, then generates rules for data records extraction. The experiments show that the system can not only complete attribute relations of separate storage extraction, but also be compatible with regular relation extraction, while maintaining high accuracy. 相似文献
144.
145.
正作为神经科学研究超级大国的美国,正拟启动尖端创新神经技术脑研究计划。该计划此前称作脑活动图计划,已经过一年多的筹备性论证。计划的主要目标是,通过包括纳米技术在内的一系列技术创新,全面构造神经活动图谱,以求在神经-精神疾病诊治及智能机开发上取得突破。围绕计划目标之可行性存在大量争鸣。 相似文献
146.
顾艳妮 《四川大学学报(自然科学版)》2010,47(3)
介绍了一种制备金属可调谐光栅的新技术。首先采用紫外光刻技术将光栅结构制作至PDMS(聚二甲基硅氧烷)基底,并在其上蒸镀金属Cr层和Ag层,然后采取金属举离工艺得到金属光栅。利用PDMS高弹性的特点,通过控制PDMS纵、横向拉伸程度,对金属光栅周期进行连续、任意调谐,获得预定的目标周期。实验结果表明,金属光栅调谐范围超过其初始周期的100%。 相似文献
147.
Dissolved organic nitrogen (DON) in the processes of polluted source water treatment 总被引:4,自引:0,他引:4
Dissolved organic nitrogen (DON) is currently considered to be one of the most important issues in drinking water field due to its formation of nitrogenous disinfection byproducts. This paper deals with DON concentrations in typical processes of a water treatment plant. The results show that very little DON is removed by these processes. Furthermore, biological activity in some processes can even increase DON concentration and decrease the ratio of dissolved organic carbon/DON, which may pose a risk to drinking water safety. 相似文献
148.
The CLC protocol (proposed by Tzung-Her Chen, Wei-Bin Lee and Hsing-Bai Chen, CLC, for short) is a new three-party password-authenticated
key exchange (3PAKE) protocol. This CLC protocol provides a superior round efficiency (only three rounds), and its resources
required for computation are relatively few. However, we find that the leakage of values A
V
and B
V
in the CLC protocol will make a man-in-the-middle attack feasible in practice, where A
V
and B
V
are the authentication information chosen by the server for the participants A and B. In this paper, we describe our attack on the CLC protocol and further present a modified 3PAKE protocol, which is essentially
an improved CLC protocol. Our protocol can resist attacks available, including man-in-the-middle attack we mount on the initial
CLC protocol. Meanwhile, we allow that the participants choose their own passwords by themselves, thus avoiding the danger
that the server is controlled in the initialization phase. Also, the computational cost of our protocol is lower than that
of the CLC protocol. 相似文献
149.
本文提出了一种结构十分简单的大口径全息平面干涉仪,理论与实验证明利用全息图的位相误差补偿作用制成大口径的全息平面干涉仪是完全可行的。 相似文献
150.
测定了烷氧基钛水解成核的诱导时间,研究了水解反应形成TiO_2超细粒子的机理,及溶剂和反应底物对水解反应机理的影响规律。导出了丁氧基钛在醇溶剂中的水解反应速率方程与对应的水解和聚结反应历程该机理同实验结果相吻合。 相似文献