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11.
Recently, the development of novel brain imaging agents has aroused much interest thanks to limited number of brain cancer or diseases diagnosis agents. It is aimed to synthesize a novel brain imaging agent including a promise for further studies on AD diagnosis potential and investigate its bioaffinity with biodistribution studies on healthy Balb/c mice. A novel radiolabeled agent was synthesized and characterized. Quality control of 99mTc-BH was performed utilizing solvent extraction and chromatographic (Radio TLC and Radio HPLC) methods. Bioaffinity of the 99mTc-BH was investigated on male Balb/c mice at various time points (5, 30, 60, 120 min post-injection). Paper electrophoresis showed that 99mTc-BH has a neutral structure. Radiochemical purity of 99mTc-BH was over 95 % with appropriate stability for imaging period. Selected brain regions have uptakes over 4 % ID/g following intravenous injection. Hippocampus has uptake approximately 10 % ID/g. 99mTc-BH has shown brain uptake, so it may prove to be valuable for brain imaging as a novel technetium-labeled agent. Further investigations with AD animal model are our on going effort to show that this agent has AD diagnosis potential.  相似文献   
12.
We point our a new class of solutions of the supersymmetric Yang-Mills equations. This class provides solutions which cannot be generated from the solutions of the ordinary Yang-Mills equations by finite supersymmetry transformations and contains the supersymmetric generalization of the non-abelian plane waves.  相似文献   
13.
For a commutative algebra R, its de Rham cohomology is an important invariant of R. In the paper, an infinite chain of de Rham-like complexes is introduced where the first member of the chain is the de Rham complex. The complexes are called approximations of the de Rham complex. Their cohomologies are found for polynomial rings and algebras of power series over a field of characteristic zero.  相似文献   
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The density of seven {(0.0087, 0.0433, 0.1302, 0.2626, 0.4988, 0.7501, and 0.9102) mole fraction of [BMIM][BF4]} binary {methanol (1) + [BMIM][BF4] (2)} (1-butyl-3-methylimidazolium tetrafluoroborate) mixtures has been measured with a vibrating-tube densimeter. Measurements were performed at temperatures from (298 to 398) K and at pressures up to 40 MPa. The total uncertainties of density, temperature, pressure, and concentration measurements was estimated to be less than 0.15 kg · m−3, 15 mK, 5 kPa, and 10−4, respectively. The uncertainties reported in this paper are expanded uncertainties at the 95% confidence level with a coverage factor of k = 2. The effect of temperature, pressure, and concentration on the density and derived volumetric properties such as excess, apparent, and partial molar volumes was studied. The measured densities were used to develop a Tait-type equation of state for the mixture. The structural properties such as direct and total correlation function integrals and cluster size were calculated using the Krichevskii function concept and the equation of state for the mixture at infinite dilution.  相似文献   
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A series of 2-(2,3,4-trimethoxyphenyl)-1-(substituted-phenyl)acrylonitrile (2–9) were designed and synthesized to develop new cancer drugs. The structures of synthesized compounds 2–9 were described by using melting point, mass (MALDI-TOF-MS), FT-IR, elemental analysis, 1H, 13C, 13C-APT and 2D NMR spectroscopy. The in vitro anticancer activities of 2–9 against human breast cancer (MCF-7), human prostate cancer (PC-3) and human ovarian cancer cells (A2780) were investigated by [3-(4,5-dimethylthiazol)-2-yl]-2,5-diphenyl-2H-tetrazolium bromide] (MTT) assay method. Additionally, the LogIC50 values of these compounds on A2780, MCF-7 and PC-3 cell lines were calculated by using inhibition % values by the GraphPad Prism 6 program on a computer. The results indicated that these compounds have high anticancer activity against MCF-7, PC-3 and A2780 cell lines (especially A2780 cell lines, p < 0.05).  相似文献   
17.
Five different orientations of the acetylene-benzene dimer including the T-shaped global minimum structure are used to assess the accuracy of the density functional theory combined with symmetry adapted perturbation theory (DFT-SAPT) approach in its density-fitting implementation (DF-DFT-SAPT) for the study of CH-pi and pi-pi interactions. The results are compared with the outcome of counterpoise corrected supermolecular calculations employing second-order M?ller-Plesset (MP2), spin-component scaled MP2 (SCS-MP2) and single and double excitation coupled cluster theory including perturbative triple excitations (CCSD(T)). For all considered orientations MP2 predicts much deeper potential energy curves with considerably shifted minima compared to CCSD(T) and DFT-SAPT. In spite of being an improvement over the results of MP2, SCS-MP2 tends to underestimate the well depth while DFT-SAPT, employing an asymptotically corrected hybrid exchange-correlation potential in conjunction with the adiabatic local density approximation for the exchange-correlation kernel, is found to be in excellent agreement with CCSD(T). Furthermore, DFT-SAPT provides a detailed understanding of the importance of the electrostatic, induction and dispersion contributions to the total interaction energy and their repulsive exchange corrections.  相似文献   
18.
The synthesis of polypentenamer by an electrochemically generated metathesis polymerization catalyst from methylene chloride solution of WCl6 was investigated. The active species formed by electroreduction of this salt under controlled potential of +900 mV at a platinum cathode with an aluminum anode were found to catalyze the ring-opening metathesis polymerization (ROMP) of cyclopentene, monocyclic olefin of relatively low strain, in high yield (89%) and at short period (32 min) under mild conditions. The effect of reaction parameters, e.g., olefin/catalyst ratio, reaction time, electrolysis time, catalyst aging, on the polymerization yield have been studied. The resulting polymer has been characterized by 1H and 13C NMR, IR and gel permeation chromatography (GPC) techniques. Analysis of the polypentenamer microstructure by means of 13C NMR spectroscopy indicates that the polymer contains a mainly trans stereoconfiguration of the double bonds (σc = 0.31) and a slightly blocky distribution (rtrc > 1) of cis and trans double bond dyads (rtrc = 1.44). However, this electrochemical system is reluctant to facilitate the competing vinyl type addition polymerization reactions.  相似文献   
19.
The adsorption of polyvinylimidazole (PVI) onto kaolinite from aqueous solutions has been investigated systematically as a function of parameters such as calcination temperature of kaolinite, pH, ionic strength, and temperature. According to the experimental results, the adsorption of PVI increases with pH from 8.50 to 11.50, temperature from 25 to 55 degrees C, and ionic strength from 0 to 0.1 mol L(-1). The kaolinite sample calcined at 600 degrees C has a maximum adsorption capacity. Adsorption isotherms of PVI onto kaolinite have been determined and correlated with common isotherm equations such as Langmuir and Freundlich isotherm models. The Langmuir isotherm model appeared to fit the isotherm data better than the Freundlich isotherm model. The physical properties of this adsorbent are consistent with the parameters obtained from the isotherm equations. Furthermore, the zeta potentials of kaolinite suspensions have been measured in aqueous solutions of different PVI concentrations and pH. From the experimental results, (i) pH strongly alters the zeta potential of kaolinite; (ii) kaolinite has an isoelectric point at about pH 2.35 in water and about pH 8.75 in 249.9 ppm PVI concentration; (iii) PVI changes the interface charge from negative to positive for kaolinite. The study of temperature effect has been quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. The dimensionless separation factor (RL) has shown that kaolinite can be used for adsorption of PVI from aqueous solutions.  相似文献   
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