A Novel Affinity Capillary Electrophoresis for the Detection of Gene Mutation Using Immobilized Oligonucleotides-Polyacrylamide Conjugate

It has been found that small mutations of certain genes are the definitive origin of many heritable disorders and cancers with striking development of recent molecular biology. Such new findings have taken close-up of the importance of gene mutation assays based on the difference of DNA base sequences in diagnostic or medical field Capillary electrophoresis can be a good candidate for an ideal method on such gene analysis, because the methods can be performed with trace amount of samples, high resolution and shorter running time. We have established an effect of oligonucleotide, which was introduced onto capillary inner surface, on the recognition of an overall sequence of sample DNA fragments as an affinity ligand.     

Solid-State Structures and Photoluminescence of Lamellar Architectures of Cu(I) and Ag(I) Paddlewheel Clusters with Hydrogen-Bonded Polar Guests

Two hexanuclear paddlewheel-like clusters appending six carboxylic-acid pendants have been isolated with the inclusion of polar solvent guests: [Cu₆(Hmna)₆]·7DMF (1·7DMF) and [Ag₆(Hmna)₆]·8DMSO (2·8DMSO), where H₂mna = 2-mercaptonicotininc acid, DMF = N,N’-dimethylformamide, and DMSO = dimethyl sulfoxide. The solvated clusters, together with their fully desolvated forms 1 and 2, have been characterized by FTIR, UV–Vis diffuse reflectance spectroscopy, TG-DTA analysis, and DFT calculations. Crystal structures of two solvated clusters 1·7DMF and 2·8DMSO have been unambiguously determined by single-crystal X-ray diffraction analysis. Six carboxylic groups appended on the clusters trap solvent guests, DMF or DMSO, through H-bonds. As a result, alternately stacked lamellar architectures comprising of a paddlewheel cluster layer and H-bonded solvent layer are formed. Upon UV illumination (λ_ex = 365 nm), the solvated hexasilver(I) cluster 2·8DMSO gives intense greenish-yellow photoluminescence in the solid state (λ_PL = 545 nm, Φ_PL = 0.17 at 298 K), whereas the solvated hexacopper(I) cluster 1·7DMF displays PL in the near-IR region (λ_PL = 765 nm, Φ_PL = 0.38 at 298 K). Upon complete desolvation, a substantial bleach in the PL intensity (Φ_PL < 0.01) is observed. The desorption–sorption response was studied by the solid-state PL spectroscopy. Non-covalent interactions in the crystal including intermolecular H-bonds, CH⋯π interactions, and π⋯π stack were found to play decisive roles in the creation of the lamellar architectures, small-molecule trap-and-release behavior, and guest-induced luminescence enhancement.     

Catalysis of 3‐Carboxy‐1,2‐benzisoxazole Decarboxylation by Hydrophobic Antibody Binding Pockets

Monoclonal antibodies were generated against a 3‐phenyl‐1,2‐benzisoxazole derivative and shown to catalyze the solvent‐sensitive decarboxylation of 3‐carboxy‐1,2‐benzisoxazoles. In addition to rate accelerations up to 2300‐fold over background, the antibodies exhibit distinctive selectivities for substrates bearing 5‐ or 6‐NO₂ substituents, with preferential decarboxylation of the less reactive substrate in one case. These effects are the likely consequence of substrate destabilization, achieved by forcing the carboxylate group into a relatively apolar binding pocket and stabilization of the charge‐delocalized transition state through dispersive interactions. Comparison with a more active antibody decarboxylase previously raised against 2‐acetamido‐naphthalene‐1,5‐disulfonate suggests, however, that a judicious mix of polar and apolar interactions may ultimately be more effective for achieving high decarboxylase activity.     

Synthesis of a star-shaped polymer via coordination of ester-linked pyridyl-terminated poly(oxyethylene) with ru(II)

The star-shaped polymer with trans-tetrapyridyl complex of Ru(II) as a core was prepared by complexation of ester-linked pyridyl-terminated poly(oxyethylene) (M̄_n = 2000) with a Ru₅Cl₁₂²⁻ cluster. The unimodal peak of the star-shaped polymer in the gel-permeation chromatogram was shifted to a higher molecular weight region than that of the starting prepolymer. The electron-withdrawing ester substituent in para position of the pyridine ring shifted the metal-to-ligand charge transfer (MLCT) band into the visible region.     

Finite element analysis of air flow around permeable sand fences

A numerical study of the turbulent air flow in a trench trap and the turbulent flow around a permeable sand fence is reported in this paper. The two-dimensional modified k–ε turbulence model proposed by Kato and Launder is used to predict the turbulent characteristics of the air flow. The discretization method for the governing equations is the three-step Taylor/Galerkin finite element method proposed by the authors. For the flow in a trench trap the numerical results are compared with experimental data obtained under realistic conditions using a large wind tunnel. For the air flow around a permeable sand fence a pressure loss model is used to represent the effect of the porosity of the fence on the flow field. © 1997 John Wiley & Sons, Ltd.     

Synthesis of Block Copolymers with a Pentasilane Core

We report a new method for the synthesis of block copolymers with a pentasilane core by the polymerization of alkyl methacrylate monomers using the pentasilyl dianion as an initiator. The polymerization proceeded with living features and yielded the corresponding block copolymers with controlled molecular weights. The amphiphilic block copolymer was obtained by the polymer reaction, and it formed sphere‐like aggregates in MeOH/H₂O solution.

     

Simultaneous observation of CO isotopomer absorption by broadband difference-frequency generation using a direct-bonded quasi-phase-matched LiNbO3 waveguide

Rovibration absorption lines both of 12CO and 13CO are observed simultaneously with the output of a 2 microm broadband difference frequency generated in a direct-bonded quasi-phase-matched LiNbO3 waveguide, which is a 50 mm device with a single quasi-phase-matching period that is operated at a constant temperature. The wavelength conversion efficiency and the difference-frequency generation bandwidth reach 100%/W and 100 nm, respectively. The idler output bandwidth in the 2 microm region is obtained by group-velocity matching or phase-mismatch minimization when a 0.94 microm pump laser diode and a 1.55 microm tunable signal source are used.     

Hydrodynamic Limit of Multiple SLE

Recently del Monaco and Schleißinger addressed an interesting problem whether one can take the limit of multiple Schramm–Loewner evolution (SLE) as the number of slits N goes to infinity. When the N slits grow from points on the real line \(\mathbb {R}\) in a simultaneous way and go to infinity within the upper half plane \(\mathbb {H}\), an ordinary differential equation describing time evolution of the conformal map \(g_t(z)\) was derived in the \(N \rightarrow \infty \) limit, which is coupled with a complex Burgers equation in the inviscid limit. It is well known that the complex Burgers equation governs the hydrodynamic limit of the Dyson model defined on \(\mathbb {R}\) studied in random matrix theory, and when all particles start from the origin, the solution of this Burgers equation is given by the Stieltjes transformation of the measure which follows a time-dependent version of Wigner’s semicircle law. In the present paper, first we study the hydrodynamic limit of the multiple SLE in the case that all slits start from the origin. We show that the time-dependent version of Wigner’s semicircle law determines the time evolution of the SLE hull, \(K_t \subset \mathbb {H}\cup \mathbb {R}\), in this hydrodynamic limit. Next we consider the situation such that a half number of the slits start from \(a>0\) and another half of slits start from \(-a < 0\), and determine the multiple SLE in the hydrodynamic limit. After reporting these exact solutions, we will discuss the universal long-term behavior of the multiple SLE and its hull \(K_t\) in the hydrodynamic limit.     

Functional organic single crystals for solid‐state laser applications

Because of long‐range order and high chemical purity, organic crystals have exhibit unique properties and attracted a lot of interest for application in solid‐state lasers. As optical gain materials, they exhibit high stimulated emission cross section and broad tunable wavelength emission as similar to their amorphous counterpart; moreover, high purity and high order give them superior properties such as low scattering trap densities, high thermal stability, as well as highly polarized emission. As electronic materials, they are potentially able to support high current densities, thus making it possible to realize current driven lasers. This paper mainly describes recent research progress in organic semiconductor laser crystals. The building molecules, crystal growth methods, as well as their stimulated emission characteristics related with crystal structures are introduced; in addition, the current state‐of‐the‐art in the field of crystal laser devices is reviewed. Furthermore, recent advances of crystal lasers at the nanoscale and single crystal light‐emitting transistors (LETs) are presented. Finally, an outlook and personal view is provided on the further developments of laser crystals and their applications.