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The fluorescence brightness of a molecular probe determines whether it can be effectively measured and its water solubility dictates if it can be applied in real-world biological systems. However, molecules brighter than the most efficient fluorescent dyes or particles brighter than quantum dots are hard to come by, especially when they must also be soluble in water. In this report, chromophoric phosphoramidites are used in a solid-state synthesis to construct functional dendrimers. When highly twisted chromophores are chosen and the proper spacers and dendrons are introduced, the resultant dendrimers emit exceptionally bright fluorescence. Chromophores, spacers, and dendrons are stitched together by efficient phosphoramidite reagents, which afford high-yield water-soluble phosphodiester linkages after deprotection. The resulting water-soluble dendrimers are exceptionally bright. [ABSTRACT FROM AUTHOR]

The dinuclear complex [Cu2(HL)2(H2O)2](ClO4)2 ( 1) [H2L = 5′-(pyridin-2-yl)-1- H,2′- H-3, 3′-bis(1, 2,4-triazole)] was obtained and fully characterized. It exhibits a centrosymmetry configuration, in which each copper(II) ion is pentacoordinate with four nitrogen atoms of two triazole ligands and one oxygen atom from a water molecule. The net atomic charges distribution and atomic orbital contribution to frontier molecular orbitals were obtained using the Gaussian 98 program with Hartree-Fock method at LANL2DZ level, indicating that the copper(II) ion has the potential to accept the electron of O2 ·-. The complex showed quasi-reversible one-electron CuII/CuI redox waves with redox potentials of -0.034 V. The SOD-like activity (IC50) of 1 was measured to be 0.18 ± 0.01 μM by xanthine/xanthine oxidase-NBT assay at pH 7.8. The relatively high SOD activity suggests that the positive charge of protonated triazole can effectively steer O2 ·- to and from the active copper ion. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles have been immobilized into an amino-functionalized metal-organic framework (MOF), MIL-101Cr-NH2, to form Pd@MIL-101Cr-NH2. Four materials with different loadings of palladium have been prepared (denoted as 4-, 8-, 12-, and 16 wt %Pd@MIL-101Cr-NH2). The effects of catalyst loading and the size and distribution of the Pd nanoparticles on the catalytic performance have been studied. The catalysts were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), N2-sorption isotherms, elemental analysis, and thermogravimetric analysis (TGA). To better characterize the palladium nanoparticles and their distribution in MIL-101Cr-NH2, electron tomography was employed to reconstruct the 3D volume of 8 wt %Pd@MIL-101Cr-NH2 particles. The pair distribution functions (PDFs) of the samples were extracted from total scattering experiments using high-energy X-rays (60 keV). The catalytic activity of the four MOF materials with different loadings of palladium nanoparticles was studied in the Suzuki-Miyaura cross-coupling reaction. The best catalytic performance was obtained with the MOF that contained 8 wt % palladium nanoparticles. The metallic palladium nanoparticles were homogeneously distributed, with an average size of 2.6 nm. Excellent yields were obtained for a wide scope of substrates under remarkably mild conditions (water, aerobic conditions, room temperature, catalyst loading as low as 0.15 mol %). The material can be recycled at least 10 times without alteration of its catalytic properties. [ABSTRACT FROM AUTHOR]

Implementation of a computer program package for automated collection and processing of rotation electron diffraction (RED) data is described. The software package contains two computer programs: RED data collection and RED data processing. The RED data collection program controls the transmission electron microscope and the camera. Electron beam tilts at a fine step (0.05-0.20°) are combined with goniometer tilts at a coarse step (2.0-3.0°) around a common tilt axis, which allows a fine relative tilt to be achieved between the electron beam and the crystal in a large tilt range. An electron diffraction (ED) frame is collected at each combination of beam tilt and goniometer tilt. The RED data processing program processes three-dimensional ED data generated by the RED data collection program or by other approaches. It includes shift correction of the ED frames, peak hunting for diffraction spots in individual ED frames and identification of these diffraction spots as reflections in three dimensions. Unit-cell parameters are determined from the positions of reflections in three-dimensional reciprocal space. All reflections are indexed, and finally a list with hkl indices and intensities is output. The data processing program also includes a visualizer to view and analyse three-dimensional reciprocal lattices reconstructed from the ED frames. Details of the implementation are described. Data collection and data processing with the software RED are demonstrated using a calcined zeolite sample, silicalite-1. The structure of the calcined silicalite-1, with 72 unique atoms, could be solved from the RED data by routine direct methods. [ABSTRACT FROM AUTHOR]

The article offers information on a study concerning fluorescent sensory microparticles which consist of molecularly imprinted polymer (MIP) and silica core. It says that the N-carbobenzyloxy-l-phenylalanine(Cbz-l-Phe or Z-l-Phe, Scheme 1) was used a template and the fluorescent monomer was developed using nitrobenzoxadiazole (NBD) fluorophore. The integration of the MIP on silica microparticles makes the assay response times and the handling of the sensor particles straightforward.

The isomerization of allylic alcohols to carbonyl compounds by a heterogeneous rhodium complex is reported. Different silica material supports and catalyst/ligand systems were evaluated. The most efficient catalyst in terms of catalytic activity and stability was found to be a cationic rhodium(I) complex with sulfonated phosphine ligands anchored on a mesoporous aluminosilica AlSBA-15. The heterogeneous complex catalyzed the isomerization of a variety of allylic alcohols in excellent yields with very low catalyst loadings (0.5 mol %). The catalyst could be recycled without significant loss of activity or selectivity. The optimized catalyst was characterized by N2 sorption, powder X-ray diffraction, transmission electron microscopy, as well as solution and solid-state nuclear magnetic resonance, and Fourier Transform infrared spectroscopies. [ABSTRACT FROM AUTHOR]

The article presents a study regarding the dielectric and mechanical properties of the expanded graphite-epoxy composites. The study investigated the composites of an expanded graphite/diglycidyl ether of bisphenol A (DGEBA) which were prepared by a simple melt blending method. The study has found that the composites presented an enhanced dielectric constant while its dynamic mechanical analysis showed an improved mechanical properties and a restricted macromolecular relaxation.

Objective: To evaluate the quality of life (QoL), health-care resource utilization, and cost for the patients with premature ventricular contractions (PVCs) by radiofrequency catheter ablation (RFCA). Methods: RFCA was performed in 58 patients with symptomatic PVCs that were refractory/easy to medication. A 24-hour ambulatory electrocardiographic monitoring, QoL, health-care resources utilization, and cost were assessed at a screening visit and 3 and 12 months after RFCA. Results: RFCA was successfully performed in 56 patients (96.6%). This resulted in a significant improvement in the QoL at 3 and 12 months after the procedure. There were no major complications related to the procedure. Nine patients (15.5%) had residual arrhythmia. Seven of them underwent repeated ablation with successful results. It also improved the QoL and reduced health-care resource utilization and cost. Conclusions: RFCA is a safe and effective treatment for PVCs, and it is a viable alternative to drugs in the presence of disabling symptoms. [ABSTRACT FROM AUTHOR]

The interaction of an electromagnetic wave with a linear array of fractally fluted chiral cylinders is considered in the present study. The mathematical manipulation is based on the boundary-value technique combined with the translational addition theorem for cylindrical wave functions, and the first-order perturbed formulation for calculating the extinction as well as scattering cross sections of the linear array is obtained, in which the multiple scattering between N parallel fractally fluted chiral cylinders is taken into consideration. [ABSTRACT FROM AUTHOR]

The multiple-scattering characteristics of a linear array of parallel rotating dielectric cylinders with finite conductivities are studied, and the normally incident wave is assumed to be either a TM or a TE polarization wave with respect to the z axis. Numerical results are presented to show the first-order velocity effect on the scattering patterns in the far zone. [ABSTRACT FROM AUTHOR]

The far-field behavior of a chirostrip dipole antenna on chiroferrite substrates is shown using the generalized spectral domain--exponential matrix technique, and such substrates are made from a nonreciprocal chiral medium and ferrite material Numerical results show that both beam scanning and pattern reshaping can be achieved by adjusting the constitutive parameters of chiroferrite, and the dispersion effects of substrates ate considered in detail. [ABSTRACT FROM AUTHOR]

In this article the radiation characteristics of .a dipole antenna on grounded composite ferrite structures are studied using the generalized spectral-domain-exponential-matrix technique. Numerical results are presented to show the effects of internal do magnetic bias fields, operating frequency, geometrical sizes, and losses of substrates on the radiation pattern and scanning characteristics of dipole antenna. The figures show that it is possible to obtain an optimum radiation pattern by choosing suitable constitutive and geometrical parameters of ferrite materials. [ABSTRACT FROM AUTHOR]

In this article a spectral-domain decoupling method of electromagnetic waves propagating and radiating of sources in bianisotropic gyroelectromagnetic chiral media is presented, and the general transmission-line-like equations for the description of field quantities (IE, VE, VM, IM) are obtained using the technique of matrix transformation, which has been developed by Tsalamengas. As a practical application, the propagation behavior of electromagnetic waves in multilayered bianisotropic gyroelectromagnetic parallel-plate chirowaveguides is investigated, and it is shown that in such a nonreciprocal chirowaveguide, propagating modes are always hybrid (EH and HE). Especially, the dyadic Green's function of sources in a grounded bianisotropic gyroelectromagnetic chiral superstrate-substrate structure is derived, and it can be directly used to analyze the radiation characteristics of gyroelectromagnetic chirostrip antennas. [ABSTRACT FROM AUTHOR]

The article describes the case of a 63-year-old woman with hepatic angiomyolipoma (HAML) presenting as an arterially enhancing liver lesion. Topics discussed include clinical features of HAML, reason that the diagnosis of HAML remains challenging, and four subtypes of HAML such as mixed, lipomatous, myomatous, and angiomatous.

The dispersion characteristics of propagating modes in a lossy parallel-plate uniaxial chiro-omega waveguide are examined, and numerical results are presented to show the influences of bianisotropy, chirality, and omega parameter on the propagation constant and attenuation rate of different hybrid modes. Furthermore, the field distributions of one- and three-order modes are demonstrated, and the lossy effect is taken into consideration. [ABSTRACT FROM AUTHOR]

The Zeolite Peacemakers The cover picture shows that a new family of materials, namely mesostructured zeolites, can bridge the gap between conventional (microporous) zeolites and surfactant‐templated (mesoporous) solids. In their Full Paper on p. 3110 ff., J. Garcia‐Martinez, X. Zou, M. Thommes and co‐workers describe how size‐tailored mesoporosity could be introduced into commercial zeolite Y crystals by a simple surfactant‐templating post‐synthetic mesostructuring process. The resulting mesoporous zeolite Y showed significantly improved product selectivity in both laboratory testing and refinery trials. A collaboration of three teams was able to characterize these materials with advanced techniques. [ABSTRACT FROM AUTHOR]

Water Splitting Catalytic water splitting is a very active research field, and many organic and inorganic catalysts have been tested for the oxidation reaction that is more challenging to catalyse at a low overpotential than the reduction reaction. Metalorganic catalysts most often survive only for short time period, so inorganic compounds are in general more promising. Several promizing oxide compounds containing cobalt have previously been identified and studied. To investigate direct synthesis of catalytically active compounds and their long time behavior, H. Svengren et al. have synthesized crystals of Co3Sb4O6F6 and the new compound CoSbO4 directly onto carbon electrodes. In their Full Paper on page 568 ff., they show the importance of making long‐term stability tests when ranking the performance of different catalysts. [ABSTRACT FROM AUTHOR]