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41.
在分布式环境中,周期性通信是安全节点间进行信息交换的主要方式。〖BP)〗针对以管理域为单元的集中式通信方案,提出了利用通信子树进行周期终止探测的算法。通过向各安全节点分配连续的、唯一的节点标识,并将标识嵌入到消息中,该算法可以利用求和公式实现通信终止判定。该算法简单而有效,算法复杂度达到最优。 相似文献
42.
Marta Vallverdú-Prats Ramon Brugada Mireia Alcalde 《International journal of molecular sciences》2022,23(2)
Arrhythmogenic cardiomyopathy is a heritable heart disease associated with desmosomal mutations, especially premature termination codon (PTC) variants. It is known that PTC triggers the nonsense-mediated decay (NMD) mechanism. It is also accepted that PTC in the last exon escapes NMD; however, the mechanisms involving NMD escaping in 5′-PTC, such as reinitiation of translation, are less known. The main objective of the present study is to evaluate the likelihood that desmosomal genes carrying 5′-PTC will trigger reinitiation. HL1 cell lines were edited by CRISPR/Cas9 to generate isogenic clones carrying 5′-PTC for each of the five desmosomal genes. The genomic context of the ATG in-frame in the 5′ region of desmosomal genes was evaluated by in silico predictions. The expression levels of the edited genes were assessed by Western blot and real-time PCR. Our results indicate that the 5′-PTC in PKP2, DSG2 and DSC2 acts as a null allele with no expression, whereas in the DSP and JUP gene, N-truncated protein is expressed. In concordance with this, the genomic context of the 5′-region of DSP and JUP presents an ATG in-frame with an optimal context for the reinitiation of translation. Thus, 5′-PTC triggers NMD in the PKP2, DSG2* and DSC2 genes, whereas it may escape NMD through the reinitiation of the translation in DSP and JUP genes, with no major effects on ACM-related gene expression. 相似文献
43.
秩函数法是循环终止性分析的主要方法,秩函数的存在表明了循环程序是可终止的.针对单分支线性约束循环程序,提出一种方法对此类循环的终止性进行分析.基于增函数法向空间的计算,该方法将原程序空间上的秩函数计算问题归结为其子空间上的秩函数计算问题.实验结果表明,该方法能有效验证现有文献中大部分循环程序的终止性. 相似文献
44.
45.
本文简介了多种现场网络与光纤网络互联的关键设备:PVC多媒体联网平台(多媒体用户接口)、光线路终端及光网络用户单元,评述了它们在小区的应用。 相似文献
46.
Antoine Debuigne Marie HurtgenChristophe Detrembleur Christine JérômeChristopher Barner-Kowollik Thomas Junkers 《Progress in Polymer Science》2012,37(7):1004-1030
The current review focuses on the relevance and practical benefit of interpolymer radical coupling methods. The latter are developing rapidly and constitute a perfectly complementary macromolecular engineering toolbox to the controlled radical polymerization techniques (CRP). Indeed, all structures formed by CRP are likely to be prone to radical coupling reactions, which multiply the available synthetic possibilities. Basically, the coupling systems can be divided in two main categories. The first one, including the atom transfer radical coupling (ATRC), silane radical atom abstraction (SRAA) and cobalt-mediated radical coupling (CMRC), relies on the recombination of macroradicals produced from a dormant species. The second one, including atom transfer nitroxide radical coupling (ATNRC), single electron transfer nitroxide radical coupling (SETNRC), enhanced spin capturing polymerization (ESCP) and nitrone/nitroso mediated radical coupling (NMRC), makes use of a radical scavenger in order to promote the conjugation of the polymer chains. More than a compilation of macromolecular engineering achievements, the present review additionally aims to emphasize the particularities, synthetic potential and present limitations of each system. 相似文献
47.
Premature termination (PT) has been identified as widespread in individual, family, and couple therapy. Unfortunately, research on PT utilizes numerous definitions of PT without providing guidance on which definition may be most clinically useful. The current study investigated seven definitions of PT (three based on therapist ratings and four based on quantitative measures) utilizing a sample of 177 couples seeking treatment at two Department of Veterans Affairs medical centers. Results indicated that PT occurred in 50–80% of couples; however, agreement between the definitions of PT was generally only in the slight to fair range, making it difficult to determine whether a particular couple was ready to terminate treatment. Additionally, many commonly used definitions of PT were unrelated to level or maintenance of relationship functioning following treatment. In contrast, two definitions of PT (ending treatment in the distressed range and therapist-rated likelihood of future unhappiness) significantly predicted larger decreases in relationship satisfaction during the 18 months following therapy, as well as lower levels of satisfaction and relationship stability 18 months after termination. Additionally, long-term relationship functioning was especially poor when both these definitions of PT were met, suggesting that both qualitative and quantitative definitions should inform decisions about termination in couple therapy. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
48.
本文采用电导法和酸度法研究了嘉华G级油井水泥浆及加有缓凝剂酒石酸时水泥的水化历程,并对酒石酸的缓凝机理进行了分析。实验结果表明:电导法较酸度法能更全面、真实地反映水泥的水化过程。 相似文献
49.
Distributed termination detection (DTD) algorithms are important since they detect globally stable states in distributed computations.
Here we introduce a new DTD mechanism, the Doomsday protocol together with its proof of correctness. Doomsday is generic since
it forms the basis for a number of new and existing DTD algorithms for which the correctness proof may be reused. The paper
describes the Doomsday protocol, provides its formal proof, derives one new DTD algorithm and shows how other hitherto unrelated
algorithms, Dijkstra–Scholten, Task Balancing and Credit Recovery, can be derived from the protocol. The paper concludes by
examining various properties of the protocol in the context of existing DTD algorithms.
This work was supported in part by Visiting Fellowship grant EPSRC GR/R84481/01 “The Doomsday Protocol” and by Australian
Research Council ARC Linkage International Grant LX0349049 “Extending a Family of Garbage Collectors”. 相似文献
50.
We propose a method to accelerate direct volume rendering using programmable graphics hardware (GPU). In the method, texture slices are grouped together to form a texture slab. Rendering non-empty slabs from front to back viewing order generates the resultant image. Considering each pixel of the image as a ray, slab silhouette maps (SSMs) are used to skip empty spaces along the ray direction per pixel basis. Additionally, SSMs contain terminated ray information. The method relies on hardware z-occlusion culling and hardware occlusion queries to accelerate ray traversals. The advantage of this method is that SSMs are created on the fly by the GPU without any pre-processing. The cost of generating the acceleration structure is very small with respect to the total rendering time. 相似文献