A highly selective and sensitive fluorescence sensing system for distinction between diphosphate and nucleoside triphosphates

Among the numerous chemosensors available for diphosphate (P(2)O(7)(4-), PPi) and nucleoside triphosphates (NTPs), only a few can distinguish between PPi and NTPs. Hence, very few bioanalytical applications based on such selective chemosensors have been realized. We have developed a new fluorescence sensing system for distinction between PPi and NTPs based on the combination of two sensors, a binuclear Zn(II) complex (1·2Zn) and boronic acid (BA), in which one chemosensor (1·2Zn) shows signal changes depending on the PPi (or NTP) concentration, and the other (BA) blocks the signal change caused by NTPs; this system enables the distinction of PPi from NTPs and is sensitive to nanomolar concentrations of PPi. The new sensing system has been successfully used for the direct quantification of RNA polymerase activity.     

Phase separated composite films of liquid crystals

Phase separation of liquid crystals from a solution with polymers has long been studied and used to prepare polymer stabilized and polymer dispersed structures. They are formed by spatially isotropic phase separation. A new mode, in which the phase separation proceeds anisotropically, has recently been discovered. Known as phase separated composite films (PSCOF), the resultant structures are made of adjacent parallel layers of liquid crystal and solidified polymer. PSCOFs have been made with nematic, ferroelectric (FLC), and antiferroelectric (AFLC) liquid crystals. Liquid crystals in PSCOFs exhibit electro-optical properties not observed in devices prepared by conventional methods, polymer dispersion, or polymer stabilization methods. Devices incorporating FLCs possess grey scale and switch 100 times faster at low fields than conventional surface stabilized devices. This method makes it possible to prepare very flexible devices and devices with liquid crystal film thickness comparable to optical wavelengths with great ease.     

Axl,Immune Checkpoint Molecules and HIF Inhibitors from the Culture Broth of Lepista luscina

Two compounds 1 and 2 were isolated from the culture broth of Lepista luscina. This is the first time that compound 1 was isolated from a natural source. The structure of compound 1 was identified via 1D and 2D NMR and HRESIMS data. Compounds 1 and 2 along with 8-nitrotryptanthrin (4) were evaluated for their biological activities using the A549 lung cancer cell line. As a result, 1 and 2 inhibited the expression of Axl and immune checkpoint molecules. In addition, compounds 1, 2 and 4 were tested for HIF inhibitory activity. Compound 2 demonstrated statistically significant HIF inhibitory effects on NIH3T3 cells and 1 and 2 against ARPE19 cells.     

Correction to: Lusztig Data of Kashiwara-Nakashima Tableaux in Type D

Algebras and Representation Theory - The original version of this article unfortunately contained a misprint. The presentation of equation (4.34) in the proof of Theorem 4.12 is incorrect.     

Highly polarised electroluminescence in low aspect ratio mesogenic molecules

We have synthesised the low aspect ratio mesogenic compounds containing one fluorene and two biphenyl moieties, and investigate their mesomorphic properties and the resultant anisotropic properties in both photoluminescence and electroluminescence. We introduced pentyloxy as a terminal flexible group in order to guarantee formation of mesophase and varied the lateral flexible group from propyl to octyl to control the mesogenic transition temperature. Eventually, in spite of the low aspect ratio mesogen, high polarisation ratio (PR) was achieved by spin-coating of luminescent nematogenic molecules. Furthermore, the PR was significantly enhanced by the additional thermal annealing process.     

Three-dimensional vibration analysis of joined thick conical — Cylindrical shells of revolution with variable thickness

A three-dimensional (3-D) method of analysis is presented for determining the free vibration frequencies of joined thick conical-cylindrical shells of revolution with variable thickness. Unlike conventional shell theories, which are mathematically two-dimensional (2-D), the present method is based upon the 3-D dynamic equations of elasticity. Displacement components u_r, u_θ, and u_z in the radial, circumferential, and axial directions, respectively, are taken to be periodic in θ and in time, and algebraic polynomials in the r and z directions. Potential (strain) and kinetic energies of the joined shells are formulated, and the Ritz method is used to solve the eigenvalue problem, thus yielding upper bound values of the frequencies by minimizing the frequencies. As the degree of the polynomials is increased, frequencies converge to the exact values. Convergence to four-digit exactitude is demonstrated for the first five frequencies. Natural frequencies are presented for different boundary conditions. Comparisons are made between the frequencies from the present 3-D Ritz method and 2-D thin shell theories by previous researchers.     

Lusztig Data of Kashiwara-Nakashima Tableaux in Type D

We describe the embedding from the crystal of Kashiwara-Nakashima tableaux in type D of an arbitrary shape into that of i-Lusztig data associated to a family of reduced expressions i which are compatible with the maximal Levi subalgebra of type A. The embedding is described explicitly in terms of well-known combinatorics of type A including the Schützenberger’s jeu de taquin and an analog of RSK algorithm.

     

A plactic algebra of extremal weight crystals and the Cauchy identity for Schur operators

We give a new bijective interpretation of the Cauchy identity for Schur operators which is a commutation relation between two formal power series with operator coefficients. We introduce a plactic algebra associated with the Kashiwara’s extremal weight crystals over the Kac–Moody algebra of type A _+∞, and construct a Knuth type correspondence preserving the plactic relations. This bijection yields the Cauchy identity for Schur operators as a homomorphic image of its associated identity for plactic characters of extremal weight crystals, and also recovers Sagan and Stanley’s correspondence for skew tableaux as its restriction.     

Directing Foldamer Self-Assembly with a Cyclopropanoyl Cap

The rational design of self-assembling organic materials is extremely challenging due to the difficulty in precisely predicting solid-state architectures from first principles, especially if synthons are conformationally flexible. A tractable model system to study self-assembly was constructed by appending cyclopropanoyl caps to the N termini of helical α/β-peptide foldamers, designed to form both N−H⋅⋅⋅O and C^α−H⋅⋅⋅O hydrogen bonds, which then rapidly self-assembled to form foldectures (foldamer architectures). Through a combined analytical and computational investigation, cyclopropanoyl capping was observed to markedly enhance self-assembly in recalcitrant substrates and direct the formation of a single intermolecular N−H⋅⋅⋅O/C^α−H⋅⋅⋅O bonding motif in single crystals, regardless of peptide sequence or foldamer conformation. In contrast to previous studies, foldamer constituents of single crystals and foldectures assumed different secondary structures and different molecular packing modes, despite a conserved N−H⋅⋅⋅O/C^α−H⋅⋅⋅O bonding motif. DFT calculations validated the experimental results by showing that the N−H⋅⋅⋅O/C^α−H⋅⋅⋅O interaction created by the cap was sufficiently attractive to influence self-assembly. This versatile strategy to harness secondary noncovalent interactions in the rational design of self-assembling organic materials will allow for the exploration of new substrates and speed up the development of novel applications within this increasingly important class of materials.     

Osteoclast-forming suppressing compounds, gargalols A, B, and C, from the edible mushroom Grifola gargal

Three novel sterols, gargalols A-C (1-3), and four known ones were isolated from the edible mushroom Grifola gargal. The structures of 1-7 were determined or identified by the interpretation of spectroscopic data. Compounds 1-5 suppressed the formation of osteoclast without toxicity.