X-ray structure of {[μ-N,N′-Bis(salicylidene)-1, 3-propane-diamine] (dimethylformamide) zinc(II)} dibromo cadmium(ii)

The title compound, forms crystals which are the orthorhombic system, space group P2 ₁2₁2₁, with unit cell dimensions a = 10.3928(12) Å, b = 14.6298(13) Å, c = 15.9514(11) Å, V = 2425.3(4) ų. The cell contains four molecules. The structure is a heteronuclear dimeric complex with Zn^II and Cd^II ions. The coordination around the Zn^II ion is distorted square–pyramid and the Cd^II ion is distorted tetrahedral coordination. The Zn·sCd distance is 3.3594(7) Å.     

Medialization Laryngoplasty With Gore-Tex: An Animal Study

Vocal cord paralysis is a disease that can cause voice disability and aspiration problems. Expanded polytetrafluoroethylene (ePTFE; Gore-Tex) has been widely used in cardiovascular and plastic surgery; however, its biocompatibility and safety have not been established precisely in the larynx. In this study, the biocompatibility and safety of ePTFE used in vocal cord medialization in the rabbit larynx were assessed. Type 1 thyroplasty with Gore-Tex was performed on one side of the larynx in eight rabbits. A sham procedure was applied on the contralateral side of their larynx. The rabbits were sacrificed after 6 months, and macroscopic and microscopic evaluations and comparisons were performed. No significant inflammatory response to Gore-Tex or displacement of the implant was seen. There was only a tiny fibrotic capsule surrounding the material in each specimen. Intense eosinophilic cell infiltration was seen surrounding one rabbit specimen. Gore-Tex seems to be a biocompatible, stable, and reversible material that can be safely used in laryngeal framework surgery.     

Deconvolution of continuous internal bremsstrahlung spectra of 32P, 85Kr and 143Pr

An efficient method of deconvolution of the internal bremsstrahlung (IB) spectra accompanying the β‐decay in ³²P, ⁸⁵Kr and ¹⁴³Pr is presented. Experimental data is taken from the literature. The usual experimental values are folded with the response matrix of the detector system, and the Gold iteration technique is employed to deconvolve the detector response function for the continuous IB photon spectra. The response function of the detector is calculated using the peak to total ratio and the energy resolution of the detector. The results of the deconvolved IB spectra along with the theoretical calculations are presented. Copyright © 2007 John Wiley & Sons, Ltd.     

On positive solutions of a reciprocal difference equation with minimum

In this paper we consider positive solutions of the following difference equation $$x_{n + 1} = \min \left\{ {\frac{A}{{x_n }},\frac{B}{{x_{n - 2} }}} \right\}, A, B > 0.$$ We prove that every positive solution is eventually periodic. Also, we present here some results concerning positive solutions of the difference equation $$x_{n + 1} = \min \left\{ {\frac{A}{{x_n x_{n - 1} ...x_{n - k} }},\frac{B}{{x_{n - (k + 2)} ...x_{n - (2k + 2)} }}} \right\}, A, B > 0.$$      

Crystal structure of [2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine]-(azido)(chloro)copper(II).

In the title compound, the coordination around the Cu atom is a distorted square-pyramid involving three N atoms from the ligand and one N atom from the azido group at the basal plane. The Cl atom is located at the apical position. The Cu atom is 0.32(5)A above the basal plane. There are three intramolecular and four weak intermolecular hydrogen bonds in the structure. IR spectra confirm the asymmetric N3 stretching vibrations of the terminal azide group.     

A generalized variational theorem in elastodynamics,with application to shell theory

Summary With a view toward the consistent derivations and numerical solutions of one- and two-dimensional approximate theories in a class of Cosserat continuum, a variational theorem is, in a straightforward manner, established by means of Hamilton's principle. By the use of this theorem, a linear theory of anisotropic shells for both extensional and flexural motions, including thermal effects, is systematically constructed. A theorem of uniqueness in this theory is then presented.

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Sommario Per mezzo del principio di Hamilton si stabilisce direttamente un teorema variazionale in vista di organiche derivazioni e soluzioni numeriche di teorie approssimate a una e a due dimensioni in una classe di continui di Cosserat. Con questo teorema si costruisce sistematicamente una teoria lineare di membrane anisotropiche per movimenti estensionali e flessionali includendo gli effetti termici. Si presenta poi in questo teorema una teoria di unicità.

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Supported by the U.S. Office of Naval Research.     

Copolymers of 2‐[(5‐Methylisoxazol‐3‐yl)amino]‐2‐oxo‐ethyl Methacrylate with Ethyl Methacrylate: Monomer Reactivity Ratios,Thermal Properties and Antimicrobial Activity

We report the monomer reactivity ratios for copolymers of ethyl methacrylate (EMA) and a reactive monomer, 2‐[(5‐methylisoxazol‐3‐yl)amino]‐2‐oxo‐ethyl methacrylate (IAOEMA), using the Fineman‐Ross, Kelen‐Tüdös, and a nonlinear error invariable model method using a computer program RREVM. Copolymers were obtained by radical polymerization initiated by α,α'‐azobisisobutyronitrile in 1,4‐dioxane solution and were analyzed by FTIR, ¹H‐NMR, and gel permeation chromatography. Elemental analysis was used to determine the molar fractions of EMA and IAOEMA in the copolymers. The reactivity ratios indicated a tendency toward ideal copolymerization. The polydispersity indices of the polymers determined using gel permeation chromatography suggest a strong tendency for chain termination by disproportionation. Thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. It was observed that glass transition temperature of copolymers increased with increasing of IAOEMA content in copolymers. Also, the apparent thermal decomposition activation energies (ΔE_d) were calculated by Ozawa method using the SETARAM Labsys TGA thermobalance. The homo‐ and copolymers were tested for their antimicrobial properties against selected microorganisms. All the products show moderate activity against different strains of bacteria, fungi and yeast.