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N/P dual-doped three-dimensional porous carbon was synthesized via nano-CaCO 3 template-assistant carbonization of intumescent flame retardants (IFRs) precursor. [Display omitted] Heteroatom-doped three-dimensional (3D) porous carbons possess great potential as promising electrodes for high-performance supercapacitors. Inspired by the inherent features of intumescent flame retardants (IFRs) with universal availability, rich heteroatoms and easy thermal-carbonization to form porous carbons, herein we proposed a self-assembling and template self-activation strategy to produce N/P dual-doped 3D porous carbons by nano-CaCO 3 template-assistant carbonization of IFRs. The IFRs-derived carbon exhibited large specific surface area, well-balanced hierarchical porosity, high N/P contents and interconnected 3D skeleton. Benefitting from these predominant characteristics on structure and composition, the assembled supercapacitive electrodes exhibited outstanding electrochemical performances. In three-electrode 6 M KOH system, it delivered high specific capacitances of 407 F g−1 at 0.5 A g−1, and good rate capability of 61.2% capacitance retention at 20 A g−1. In two-electrode organic EMIMBF 4 /PC system, its displayed high energy density of 62.8 Wh kg−1 at a power density of 748.4 W kg−1, meanwhile it had excellent cycling stability with 84.7% capacitance retention after 10,000 cycles. To our best knowledge, it is the first example to synthesize porous carbon from IFRs precursor. Thus, the current work paved a novel and low-cost way for the production of high-valued carbon material, and expanded its application for high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

Abstract: George Szekeres described some subsets of without arithmetic progressions of length p for odd primes p, obtained by a greedy algorithm. Let denote the size of the largest subset of without arithmetic progressions of length k. In this paper, the history of results based on the constructions by Szekeres is briefly surveyed. New inequalities for and van der Waerden numbers are derived by generalizing these constructions. In particular, for any odd prime p, we prove that , where . [Copyright &y& Elsevier]

Abstract: Mesh is an important and popular interconnection network topology for large parallel computer systems. A mesh can be divided into submeshes to obtain the upper bounds on the connection probability for the mesh. Combinatorial techniques are used to get closer upper bounds on the connection probability for 2-D meshes compared with the existing upper bounds we have known. Simulation results of meshes of various sizes show that our upper bounds are close to the exact connection probability. The combinatorial methods and tools used in this paper can be used to study the connection probabilities for other networks. [Copyright &y& Elsevier]

Abstract: For given graphs , the three-color Ramsey number is defined to be the least positive integer such that every 3-coloring of the edges of complete graph contains a monochromatic copy of colored with , for some . In this paper, we prove that , , , , for ; , , for . [Copyright &y& Elsevier]

Codon bias at the 5′ terminal of coding sequence (CDS) is known to be distinct from the rest of the CDS. A number of events occur in this short region to regulate early translation elongation and co-translational translocation. In the genes encoding secretory proteins, there is a special signal sequence which has a higher occurrence of rare codons. In this study, we analyzed codon bias of secretory genes in several eukaryotes. The results showed that secretory genes in the species except mammals had a higher occurrence of rare codons in the 5′ terminal of CDS, and the bias was greater than the same region of non-secretory genes. GO analysis revealed that secretory genes containing rare codon clusters in different regions were responsible for various roles in gene functions. Moreover, codon bias in the region encoding the hydrophobic region of protein is similar in secretory and non-secretory genes, indicating that codon bias in secretory genes was partly influenced by amino acid bias. Rare codon clusters are found more frequently in specific regions, and continuous rare codons are not favoured probably because they will increase the probability of ribosome collision and drop-off. Based on ribosome profiling data, there is no significant difference in the average translation efficiencies between rare and optimal codons. Higher ribosomal density in the 5′ terminal may result from ribosome pausing which could be involved in different translation events. These findings collectively provided rich information on codon bias in secretory genes, which may shed light on the co-effect of codon bias, mRNA structure and tRNA abundance in translational regulations. [ABSTRACT FROM AUTHOR]

Abstract: For positive integers n and k, let be the size of the largest subset of without arithmetic progressions of length k. The van der Waerden number is the smallest integer w such that every r-coloring of contains a monochromatic -term arithmetic progression with color i for some i. In this note, an algorithm is proposed to search exact values of for some k and n, and some new exact values of for are obtained. The results extend the previous ones significantly. It is also shown that for prime , and three lower bounds for van der Waerden numbers are given: , , . [Copyright &y& Elsevier]