A Preliminary Study of Crassulacean Acid Metabolism (CAM) in the Endangered Aquatic Quillwort Isoetes sinensis Palmer in China

Isoetes sinensis Palmer (Isoetaceae) is an aquatic or amphibious plant that is critically endangered in China. Previous studies have revealed the crassulacean acid metabolism (CAM)-like photosynthetic pathway occurs commonly in submerged leaves in genus Isoetes. Water chemistry parameters and the titratable acidity content of the plant extract were measured from samples obtained in the early morning (7:00) and late afternoon (15:00) from two I. sinensis populations in China. One population occurs in the eulittoral zone of a freshwater tidal river at low elevation (134 m) and another occurs in a densely vegetated, high elevation (1 100 m) alpine shallow pool. Significant differences in pH and titratable acidity of the plant extract were detected between the morning and afternoon samples. These changes are associated with diurnal changes in water chemistry. Our results provide the first evidence for the existence of the CAM pathway in the East Asian endemic Isoetes sinensis Palmer. The magnitude of fluctu     

一个非凸最小化定理与Ekeland变分原理等价

本文证明了一个非凸最小化定理。并利用它证明了Ekeland变分原理,和Caristi不动点定理,且由此证明非凸最小化定理与Ekeland变分原理,Caristi不动点定理等价。     

基于元胞退火算法的网络生存性研究

针对通信网络因链路失效而产生的网络拥塞问题,结合元胞自动机和模拟退火算法提出了一种新的网络生存性评价方法SACA(Survivability Algorithm based on Cellular Annealing).该方法首先给出了网络生存性定义,并且通过元胞演化规则来改进模拟退火算法中的变异和交叉操作,以此获得网络剩余数据传输量.同时,利用NS2和MATLAB进行仿真实验,深入研究了网络有效性与失效边数等影响因素之间的关系.结果表明,相比于其它算法,SACA算法具有较好的适应性.     

An overview of the switching parameter variation of RRAM

Resistive random access memory（RRAM） has been considered as one of the most promising candidates for next-generation nonvolatile memory, due to its advantages of simple device structure, excellent scalability, fast operation speed and low power consumption. Deeply understanding the physical mechanism and effectively controlling the statistical variation of switching parameters are the basis of fostering RRAM into commercial application. In this paper, based on the deep understanding on the mechanism of the formation and rupture of conductive filament, we summarize the methods of analyzing and modeling the statistics of switching parameters such as SET/RESET voltage, current, speed or time. Then, we analyze the distributions of switching parameters and the influencing factors. Additionally, we also sum up the analytical model of resistive switching statistics composed of the cell-based percolation model and SET/RESET switching dynamics. The results of the model can successfully explain the experimental distributions of switching parameters of the Ni O- and Hf O2-based RRAM devices. The model also provides theoretical guide on how to improve the uniformity and reliability such as disturb immunity. Finally, some experimental approaches to improve the uniformity of switching parameters are discussed.     

Diurnal variation of hue discriminatory capability under artificial constant illumination

Diurnal variation of hue discriminatory capability under artificial constant illumination of 4000 lux was studied with 10 young female adults using the 100-hue test. There were conspicuous diurnal variations in the yellow-blue and red-green systems, with marked reductions of error score in the evening. However, observations of the blue, yellow, green and red systems separately disclosed that there existed clear diurnal rhythms in the blue and green systems, but not in the yellow and red systems. This suggests the existence of diurnal variation in function of the S and M cones responsible for the blue and green hue.     

海莲林土壤CH4通量的日变化和滩面差异

采用静态密闭箱法研究了海南岛东寨港海莲（Ｂｒｕｇｕｉｅｒａｓｅｘａｎｇｕｌａ）林土壤ＣＨ４通量的日变化和滩面差异，结果表明：位于中高潮带而土壤较为湿润的长宁海莲林ＣＨ４通量高于位于高潮带而土壤较为干燥的河港海莲林，其土壤平均ＣＨ４通量分别为０．４９６和０．０８４ｍｇ／ｍ２．ｄ；长宁海莲林土壤ＣＨ４通量呈现较大的日变化，林地受潮水淹没时的ＣＨ４通量一般低于不受潮水淹没时的值，土壤ＣＨ４通量的日变化与气温和土温（５ｃｍ深）相关不显著；长宁海莲林与河港海莲林土壤ＣＨ４通量呈相同的滩面差异规律，即下部滩面＞中部滩面＞上部滩面．     

番石榴变异类型在攀西地区的发现及其意义

通过对攀西地区野生番石榴Psidium guajava Linn．的实地调查，发现了一种新的变异类型，它属于番石榴的小叶和小果类型。经过我们的研究认为，这种番石榴变异新类型在我国尚属于首次发现。它的发现不仅对摸清攀西地区以及我国的番石榴种质资源，深入研究其变异特点具有重要的学术研究价值，而且在改良品种，提高品质上也具有重大的经济意义。     

传染性法氏囊病病毒结构的分子生物学研究进展

传染性法氏囊病是一种严重危害雏鸡的免疫抑制性、高度接触性传染病.传染性法氏囊病病毒为双RNA病毒,有A、B两个片断.A片断编码4种蛋白VP2,VP3,VP4和VP5,B片断编码VP1蛋白.其中的VP2和VP3是主要的宿主保护性抗原,在病毒的结构、变异、毒力和免疫原性方面有着重要的作用.     

金线巴鱼属两亚种mtDNA的序列变异(英文)

对抚仙金线巴鱼和滇池金线巴鱼的线粒体细胞色素ｂ基因的部分序列进行了测定及分析。发现①两亚种间共有３８个变异位点,占总位点的１０．９％;②转换明显多于颠换,且第三位置上的同义突变最为常见;③两亚种间的遗传距离为０．１１４,高于已研究过的淡水鱼类种内遗传距离的最大值,接近种间的较高值,是否仍然把它们视为同种的两个亚种看来值得进一步研究。     

工业分布参数系统的最优控制

本文结合实际工业过程讨论了分布参数系统的最优控制问题。内容包括有关分布参数系统的极大值原理,最优化必要条件和最优控制计算方法等。虽然分布参数问题的分析和计算远比集中参数复杂和困难,尤其是在处理多维系统时有可能出现“维数灾难”,但研究结果表明所采用的方法提供了有效地实现最优控制的可能性。