Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the a...

Abstract This letter will clarify the fundamental properties of a quaternary neuron whose weights, threshold values, input and output signals are all quaternions, which is an extension of a usual real-valued neuron to quaternions. The main results of this letter are summarized as follows. A quaternary neuron has an orthogonal decision boundary. The 4-bit parity problem which cannot be solved wi...

Eubacterial and related single-stranded DNA-binding proteins (SSBs) exhibit considerable variability in their quaternary association in spite of their having the same tertiary fold. The variability involves differences in the orientation of dimers in the tetrameric molecule (or of two-domain subunits in the dimeric molecule) and that of monomers in each dimer. The presence of an additional stra...

The Quaternary in the state of Rio Grande do Sul (RS), southern Brazil, is geologically represented by the coastal plain and was originated by successive events of Pleistocene-Holocene marine transgressions and the occurrence of alluvial deposits. This paper aimed to characterize the fish assemblage occurring in a swampy Quaternary area adjacent to Lagoa Pequena, a lacustrine system connected t...

Endogenous quaternary ammonium compounds are involved in various physiological processes in the central nervous system. In the present study, eleven quaternary ammonium compounds, including acetylcholine, choline, carnitine, acetylcarnitine and seven other acylcarnitines of low polarity, were analyzed from brain extracts using a two dimension capillary liquid chromatography-Fourier transform ma...

Functional diversity based on species traits is a powerful tool to investigate how changes in species richness and composition affect ecosystem functioning. However, studies aimed at understanding changes in functional diversity over large temporal and spatial scales are still scant. Here we evaluate the combined effect of diversification and species sorting on functional diversity of fossil ma...

We developed a modified complex of pDNA and poly-l-lysine (PLL) by the addition of poly-l-histidine (PLH) and γ-polyglutamic acid (γ-PGA) to enhance its pH-buffering effect and suppress cytotoxicity. The binary and ternary complexes of pDNA with PLL or/and PLH showed particle sizes of approximately 52-76 nm with cationic surface charge. The ternary complexes showed much higher gene expression t...

In this paper, -valued quadratic forms defined on a vector space over are studied. A classification of such forms is established, distinguishing -valued quadratic forms only by their rank and whether the associated bilinear form is alternating. This result is used to compute the distribution of certain exponential sums, which occur frequently in the analysis of quaternary codes and quaternary s...

An high-performance liquid chromatography (HPLC) method for identification of quaternary and non-quaternary compounds (parent compounds, intermediates, by-products, and products) within the synthesis of the acetylcholinesterase reactivator HI-6, the most promising antidote of nerve agent poisonings, is described. This HPLC method could be of high interest as a quick purity control for those who...

MOTIVATION The 'sequence implies conformation' principle has been the motivation for the construction of numerous systems of secondary and tertiary structure prediction. Computational experiments have shown that this principle can now be extended to quaternary structure prediction. This work appears to be the first effort to predict quaternary structure properties from sequence. RESULTS The s...