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71.
72.
火电厂主、辅机及辅助设备顺序控制系统的发展 总被引:5,自引:3,他引:5
回顾国内、外火电厂顺序控制系统的发展,特别介绍35a来我国顺序控制系统经历的起步阶段,以程序控制器(PLC)为核心硬件的中期阶段和主、辅机顺序控制系统融入分散控制系统(DCS阶段、现场总线控制系统(FCS)介入阶段,并对由不同形式组成的顺序控制系统的特点进行评价,展望下一世纪该系统的发展趋势。 相似文献
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75.
Jin Chai Ling Luo Zehuai Yu Jiawei Lei Muqing Zhang Zuhu Deng 《International journal of molecular sciences》2022,23(12)
The barcode probe is a convenient and efficient tool for molecular cytogenetics. Tripidium arundinaceum, as a polyploid wild allied genus of Saccharum, is a useful genetic resource that confers biotic and abiotic stress resistance for sugarcane breeding. Unfortunately, the basic cytogenetic information is still unclear due to the complex genome. We constructed the Cot-20 library for screening moderately and highly repetitive sequences from T. arundinaceum, and the chromosomal distribution of these repetitive sequences was explored. We used the barcode of repetitive sequence probes to distinguish the ten chromosome types of T. arundinaceum by fluorescence in situ hybridization (FISH) with Ea-0907, Ea-0098, and 45S rDNA. Furthermore, the distinction among homology chromosomes based on repetitive sequences was constructed in T. arundinaceum by the repeated FISH using the barcode probes including Ea-0663, Ea-0267, EaCent, 5S rDNA, Ea-0265, Ea-0070, and 45S rDNA. We combined these probes to distinguish 37 different chromosome types, suggesting that the repetitive sequences may have different distributions on homologous chromosomes of T. arundinaceum. In summary, this method provide a basis for the development of similar applications for cytogenetic analysis in other species. 相似文献
76.
In this paper, based on a result of Lidl and Mullen (Mathematical Journal of Okayama University, 1991), the maximum length and the second maximum length that can be attained by cycles of Dickson permutation polynomial (of the first kind) with parameter 1 are studied. Necessary and sufficient conditions for these two lengths to be attained are given, which are connected with Fermat primes and Mersenne primes, respectively. Furthermore, a class of coordinate sequences that maintains a large period is obtained, which is shown to be the coordinate sequences derived from cycles of the second maximum length. Explicit formulas for their periodicity and shift-equivalences are also presented. 相似文献
77.
Kazuhiro Maeta Manal Farea Hisahide Nishio Masafumi Matsuo 《International journal of molecular sciences》2022,23(9)
Antisense oligonucleotides (ASOs) are agents that modulate gene function. ASO-mediated out-of-frame exon skipping has been employed to suppress gene function. Myostatin, encoded by the MSTN gene, is a potent negative regulator of skeletal muscle growth. ASOs that induce skipping of out-of-frame exon 2 of the MSTN gene have been studied for their use in increasing muscle mass. However, no ASOs are currently available for clinical use. We hypothesized that ASOs against the splicing enhancer sequence within exon 1 of the MSTN gene would inhibit maturation of pre-mRNA, thereby suppressing gene function. To explore this hypothesis, ASOs against sequences of exon 1 of the MSTN gene were screened for their ability to reduce mature MSTN mRNA levels. One screened ASO, named KMM001, decreased MSTN mRNA levels in a dose-dependent manner and reciprocally increased MSTN pre-mRNA levels. Accordingly, KMM001 decreased myostatin protein levels. KMM001 inhibited SMAD-mediated myostatin signaling in rhabdomyosarcoma cells. Remarkably, it did not decrease GDF11 mRNA levels, indicating myostatin-specific inhibition. As expected, KMM001 enhanced the proliferation of human myoblasts. We conclude that KMM001 is a novel myostatin inhibitor that inhibits pre-mRNA maturation. KMM001 has great promise for clinical applications and should be examined for its ability to treat various muscle-wasting conditions. 相似文献
78.
Erinija Pranckeviciene Sergey Hosid Indiras Maziukas Ilya Ioshikhes 《International journal of molecular sciences》2022,23(9)
Nucleosomes are basic units of DNA packing in eukaryotes. Their structure is well conserved from yeast to human and consists of the histone octamer core and 147 bp DNA wrapped around it. Nucleosomes are bound to a majority of the eukaryotic genomic DNA, including its regulatory regions. Hence, they also play a major role in gene regulation. For the latter, their precise positioning on DNA is essential. In the present paper, we describe Galaxy dnpatterntools—software package for nucleosome DNA sequence analysis and mapping. This software will be useful for computational biologists practitioners to conduct more profound studies of gene regulatory mechanisms. 相似文献
79.
刚果盆地钾盐矿床沉积特征及成因探讨 总被引:2,自引:0,他引:2
刚果盆地是低纬度重要的成盐盆地,主要由白垩系、新近系和第四系组成。含盐地层赋存于白垩纪地层中部,其下伏陆相碎屑岩沉积,上覆海相碎屑—碳酸盐岩沉积。盐层包括5种沉积层序,盐类矿物析出顺序是:硬石膏—石盐—光卤石—水氯镁石—溢晶石。研究区钾盐矿和石盐矿共生,钾盐矿层有20层,累计平均厚度259.61m,KCl品位大于15%。矿石类型主要为光卤石型,次为钾石盐型。矿石为滨海—泻湖相沉积蒸发岩,其沉积与大西洋裂谷的演化发展密切相关,是白垩纪裂谷发育期间,由初始浓缩沉积的富含卤化物海水运移至次级盆地进一步蒸发沉积形成。 相似文献
80.
传统的单服务器环境下基于智能卡认证方案,单个服务器对所有的注册远程用户提供服务。如果用户想要从不同的服务器获得网络服务,则必须分别在不同的服务器注册。为解决以上问题,研究者提出了多服务器认证方案。然而,文献中的大部分方案都不能实现强安全特性。受到切比雪夫映射的半群特性和基于扩展混沌映射的密钥协商协议启发,本文提出一种多服务器环境中的认证方案。新方案不需要使用验证表并且允许用户访问不同的服务器而不需要分别注册。新方案不仅可以抵抗各类攻击,还实现了用户的强匿名性。和以前的相关协议相比,新协议具有高效性和安全性,因而适合在实际环境中应用。 相似文献