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311.
Relationships between D1 protein, xanthophyll cycle and photodamage-resistant capacity in rice (Orysa sativa L.) 总被引:1,自引:0,他引:1
Relationships between D1 protein, xanthophyll cycle and subspecific difference of photodamage-resistant capacity have been studied in O. japonica rice varieties 02428 and 029 (photoinhibition-tolerance) and O. indica rice varieties 3037 and Palghar (photoinhibition-sensitivity) and their reciprocal cross F1 hybrids after photoinhibitory treatment. It was shown that PSⅡ photochemical efficiency (Fv /Fm) decreased, and xanthophyll cycle from violaxanthin (V), via anaxanthin (A), to zeaxanthin (Z) was enhanced and non-photochemical quenching (qN) increased accordingly in SM-pretreated leaves of rice when the synthesis of D1 protein was inhibited, and that there was a decrease in qN and, as a result, more loss of D1 protein and a big decrease in Fv /Fm in DTT-pretreated leaves when xanthophyll cycle was inhibited. O. japonica subspecies had a higher maintaining capacity of D1 protein and a decrease of Fv /Fm in a more narrow range, and exhibited more resistance against photodamage, as compared with O. indica subspecies. The above physiological indexes in reciprocal cross F1 hybrids, though between the values of their parents, were closer to maternal lines than to paternal lines. Experimental results support the concept that the turnover capacity for D1 protein is an important physiological basis of photoinhibition-tolerance, and will provide the physiological basis for selection of the photoinhibition-tolerant parents and develop a new approach to breed hybrids with high photosynthetic efficiency. 相似文献
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314.
向阳 《武汉科技学院学报》1999,(3)
利用微机也能实现机械凸轮的功能,转换回转运动为直线运动。在微机上这种以软件形式合成的凸轮不但完全可以代替机械凸轮,而且还能克服纯粹的机械凸轮所存在的一些缺点 相似文献
315.
利用PIC16C62单片机的I/O接口和定时捕捉功能,来获取比较器产生电位跳变的时间;通过对RC充电特性曲线的计算,实现A/D转换。 相似文献
316.
The female-produced sex pheromone of Dendrolimus superans was identified by gas chromatography (GC), coupled GC-mass spectrometry (GC-MS), electroantennographic (EAG) studies and field tests as a blend of (Z,E)-5,7-dodecadienal (Z5,E7-12:Ald) and (Z,E)-5,7-dodeca- dien-1-ol (Z5,E7-12:OH). In D. kikuchii, (Z,E)-5,7-dodeca- dien-1-yl acetate (Z5,E7-12:OAc) and Z5,E7-12:OH were found by GC and GC-MS analyses. However, in EAG studies male antennae were more sensitive to Z5,E7-12:OAc and (Z,E)-5,7-dodecadien-1-yl propionate (Z5,E7-12:OPr) than Z5,E7-12:OH. For D. spectabilis, Z5,E7-12:OH had been previously reported as the sex pheromone. However, in our studies, traps baited with Z5,E7-12:OH, Z5,E7-12:OAc and Z5,E7-12:OPr in a ratio of 1:1:1 caught three times more males than those baited with Z5,E7-12:OH alone. Relatively strong EAG responses were elicited from male antennae by Z5,E7-12:OH, Z5,E7-12:OAc and Z5,E7-12:OPr, but in addition to Z5,E7-12:OH, only very small amounts of Z5,E7- 12:OAc was found in the pheromone gland. These facts suggest that Z5,E7-12:OAc is a pheromone minor components and Z5,E7-12:OPr is a sex attractant in D. spectabilis. For D. tabulaeformis, Z5,E7-12:OH, Z5,E7-12:OAc and Z5,E7-12: OPr were found in extracts of pheromone glands of female moths, and the three compounds elicited strong EAG responses from antennae of male moths. These three compounds have been reported as a sex attractant of D. tabulaeformis, and our data confirm their roles as components of the sex pheromone of this species. The role of blend components in antagonizing cross attraction between congeners is discussed. 相似文献
317.
分析了3DGIS的功能、研究内容以及缺陷.通过对3DGIS和2DGIS比较得出二、三维一体化的必要性.运用Supermap.Deskpro.Net建立三维场景,进行山体和城市三维建模、城市三维快速建模、二、三维一体化搡作、联动显示、属性修改、SQL查询等,研究二、三雏一体化的特点和优势,并对相关问题进行探讨. 相似文献
318.
通过CT扫描 ,可获得病人的定位层面图象 .然而 ,医师在头脑中很难建立立体化模型 ,且难以准确定位 .本软件系统将人体的各个器官及病变部位还原为三维立体 ,并实现旋转、着色、放大、缩小等功能 ,为医师的治疗计划提供强有力的依据 . 相似文献
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虚拟现实中自然现象的模拟一直都是研究的热点,其中雨雪天气的模拟可以增加虚拟现实的逼真程度.本文在分析粒子系统实现原理的基础上,基于Direct3D技术,实现了雨雪天气的模拟.本文采用的实现方法比较简单,实现效果具有较强的真实感. 相似文献