High rates of sexual contact with female sex workers, sexually transmitted diseases, and condom neglect among HIV-infected and uninfected men with tuberculosis in Abidjan, C?te d''Ivoire

We assessed mechanisms of acetylcholine- and bradykinin-induced relaxations in human omental resistance vessels. Ring segments (approximately 200 microns normalized ID) were dissected from omental biopsies obtained from women at laparotomy (nonpregnant) or at cesarean delivery (pregnant) and were studied under isometric conditions in a Mulvany-Halpern myograph. All arginine vasopressin-preconstricted vessels relaxed in a strictly endothelium-dependent manner to acetylcholine and bradykinin; maximal relaxations were not decreased by either NG-nitro-L-arginine or indomethacin. By contrast, bradykinin failed to relax vessels that had been preconstricted with potassium gluconate. In the combined presence of NG-nitro-L-arginine and indomethacin, addition of charybdotoxin, a selective antagonist of some calcium-sensitive potassium channels, did not inhibit maximal bradykinin-induced relaxation. By contrast, addition of 10 mmol/L tetraethylammonium chloride abolished relaxation in vessels from nonpregnant women but not in vessels from gravidas. We conclude that bradykinin relaxes these human resistance arteries in an endothelium-dependent but predominantly nitric oxide- and prostanoid-independent manner; relaxation likely depends on the action of an endothelium-derived hyperpolarizing vasodilator. Furthermore, in striking contrast to mechanistic insights from animal studies, human pregnancy appears to augment a mechanism of endothelium-dependent relaxation in these vessels that is insensitive to the inhibitors noted above. Whether a similar novel vasodilator mechanism in vivo contributes to the physiological vasodilation that characterizes human gestation or whether failure of such a mechanism might lead to preeclampsia remains the subject of future study.     

Nature of Linear Spectral Properties and Fast Electronic Relaxations in Green Fluorescent Pyrrolo[3,4-c]Pyridine Derivative

The electronic nature of 4-hydroxy-1H-pyrrolo[3,4-c]pyridine-1,3,6(2H,5H)-trione (HPPT) was comprehensively investigated in liquid media at room temperature using steady-state and time-resolved femtosecond transient absorption spectroscopic techniques. The analysis of the linear photophysical and photochemical parameters of HPPT, including steady-state absorption, fluorescence and excitation anisotropy spectra, along with the lifetimes of fluorescence emission and photodecomposition quantum yields, revealed the nature of its large Stokes shift, specific changes in the permanent dipole moments under electronic excitation, weak dipole transitions with partially anisotropic character, and high photostability. Transient absorption spectra of HPPT were obtained with femtosecond resolution and no characteristic solvate relaxation processes in protic (methanol) solvent were revealed. Efficient light amplification (gain) was observed in the fluorescence spectral range of HPPT, but no super-luminescence and lasing phenomena were detected. The electronic structure of HPPT was also analyzed with quantum-chemical calculations using a DFT/B3LYP method and good agreement with experimental data was shown. The development and investigation of new pyrrolo[3,4-c]pyridine derivatives are important due to their promising fluorescent properties and potential for use in physiological applications.     

Polyamine functionalized glycidyl methacrylate terpolymers as scavengers for metal ions uptake from organic solutions

Resins with amine functionalities were obtained as a result of chemical modification of low crosslinked terpolymers of glycidyl methacrylate with styrene and divinylbenzene or diethylene glycol dimethacrylate. The loading of amine groups, swelling in the selected organic solvents, and thermal properties of the resins were studied. FTIR, DSC, TGA, SEM, and stereomicroscopy methods were also applied for exploring of the resins. The amine functionalized resins were tested as sorbents for uptake of cobalt(II), copper(II), iron(III), and manganese(II) ions from methanol and its mixtures with methylene chloride. The study show that all polyamine functionalized resins uptake quickly Cu(II) ions from methanol solutions. Their ability to remove cobalt(II), iron(III), and manganese(II) ions from solution depended on the mutual compatibility of solvents and resins. It increases clearly when the mixtures of methanol and methylene chloride are applied. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Accelerated weathering of cementitious matrix for the development of an accelerated laboratory test of biodeterioration

Cement based materials are porous, may contain organic adjuvants, and thus possesses an important primary bioreceptivity. To preserve constructions from fungal colonization and to act efficiently against fungal biodeterioration, it is necessary to have a better understanding of biodeterioration mechanisms and its effects on materials properties. An accelerated laboratory test which allows us to compare the growth of three fungal strains and the aesthetic biodeterioration of a cementitious matrix was developed. As the surface pH of the fresh cement specimen is too high to allow fungal growth (pH ~12), accelerating weathering of the matrix, consisting of the combination of carbonation and leaching, was performed to reduce the matrix alkalinity. XRD analyses and SEM observations pointed out that the matrix surface is progressively covered by a calcium carbonate layer as the weathering increases. Results point out that the microbial growth occurs on matrix with a surface composition more like a limestone than a cementitious one.     

Three‐component terpolymers of glycidyl methacrylate with good swelling characteristics

Highly swellable glycidyl methacrylate terpolymers with styrene and a series of crosslinkers (divinyl benzene and ethylene, diethylene, and triethylene glycol dimethacrylates) were obtained by suspension polymerization. The loading capacities of the resins, their glass‐transition temperatures, and their swelling characteristics in 20 solvents were examined with respect to the monomer composition. A selected resin was modified for a cobalt–imine complex and tested as a catalyst in a model ring‐opening reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

彩色顺序制液晶显示器的快速液晶开关

本文中,研究制成了含有液晶材料异硫氰酸根二苯乙炔和异硫氰酸根三联苯的较高双折射(0.3<△n<0.4)和相对低粘性的液晶混合物。制作了用于顺序制彩色液晶显示器的扭曲相列式液晶薄盒(TN),盒厚为1.6μm,研究证明了其响应时间为1ms。     

Single Dose of N-Acetylcysteine in Local Anesthesia Increases Expression of HIF1α, MAPK1, TGFβ1 and Growth Factors in Rat Wound Healing

In this study, we aimed to investigate the influence of N-acetylcysteine (NAC) on the gene expression profile, neoangiogenesis, neutrophils and macrophages in a rat model of incisional wounds. Before creating wounds on the backs of 24 Sprague–Dawley rats, intradermal injections were made. Lidocaine–epinephrin solutions were supplemented with 0.015%, 0.03% or 0.045% solutions of NAC, or nothing (control group). Scars were harvested on the 3rd, 7th, 14th and 60th day post-surgery. We performed immunohistochemical staining in order to visualize macrophages (anti-CD68), neutrophils (anti-MPO) and newly formed blood vessels (anti-CD31). Additionally, RT-qPCR was used to measure the relative expression of 88 genes involved in the wound healing process. On the 14th day, the number of cells stained with anti-CD68 and anti-CD31 antibodies was significantly larger in the tissues treated with 0.03% NAC compared with the control. Among the selected genes, 52 were upregulated and six were downregulated at different time points. Interestingly, NAC exerted a significant effect on the expression of 45 genes 60 days after its administration. In summation, a 0.03% NAC addition to the pre-incisional anesthetic solution improves neovasculature and increases the macrophages’ concentration at the wound site on the 14th day, as well as altering the expression of numerous genes that are responsible for the regenerative processes.     

轮铲式挖掘机新一代驾驶室隔震系统的优化

 提出新一代驾驶室计算机辅助设计的一些观点,重点关注驾驶室隔振系统的原始设计方案,它由挖掘悬臂连同驾驶室悬臂组成。用有限元法对驾驶室动态特性进行了分析,在虚拟模型数值分析的基础上形成一个方案,随后建立一个带有隔振系统的驾驶室原型样模,实体振动测量提供了非常令人满意的结果。     

Characterization of a de novo 48,XX,+r(X),+r(17) by in situ hybridization in a patient with neurofibromatosis (NF1)

The authors analyze the errors in the treatment of detachment of the retina in children. The errors were found not only in the surgical policy, but in the management of the pre- and postoperative period as well. They suggest rational methods for the pre- and postoperative management of patients with detachment of the retina and adequate schemes of surgical treatment.     

Derivation of operational matrices of differentiation for orthogonal polynomials

A direct method for deriving an operational matrix of differentiation for Legendre polynomials is presented. The general case is also considered. The presented formulas are formally proved. Results are compared with the other known method. The new method is accurate for all matrix dimensions, while the other method may fail for higher dimensions.