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Discovering fluorescence of existing compounds, which are generally regarded as non-fluorescent, is of important academic and technical significance. This article reports the fluorescence of common compounds containing pyrrolidone ring(s) and their oxidized hydrolyzates. Poly( N-vinylpyrrolidone) (PVP), polymerized from a very weak fluorescent monomer N-vinyl-2-pyrrolidone (NVP), exhibits strong intrinsic fluorescence. Moreover, the fluorescence of its 'hydrolyzate' is dramatically enhanced by about 1000 times. The 'hydrolyzate' of N-methyl-pyrrolidone (NMP) also exhibits significantly enhanced fluorescence. By studying the chemical structures and fluorescence of the hydrolyzates, the enhanced fluorescence is attributed to the formation of secondary amine oxide. The much stronger fluorescence of the polymers compared to the corresponding small molecular compounds is ascribed to the 'aggregation-induced emission' (AIE) effect of the luminophores. PVP and its oxidized hydrolyzate also show some phenomena different to the common AIE effect. The fluorescence of PVP and its oxidized hydrolyzate shows stimuli response to metal ions and pH values. This study introduces novel fluorescent materials for various potential applications. [ABSTRACT FROM AUTHOR]

Abstract: A method for measuring the thermal conductivity (k) of small molecule organic solid materials using modulated differential scanning calorimetry (MDSC) is demonstrated. Sample preparation required powder consolidation, unavoidably introducing air voids into compacts. Supporting equations for the technique were modified to include a porosity term (ɛ), and the theoretical quadratic relationship between k and ɛ was confirmed by experimental measurements for 18 representative materials. Zero-porosity extrapolation was used to approximate values of “true” thermal conductivity for non-porous solids (k ɛ=0). Zero-porosity-extrapolated values ranged from 0.1273W/(Km) to 0.3472W/(Km) for all materials, consistent with expected values of k for non-porous organic polymers. [Copyright &y& Elsevier]

The potential for small molecule organic crystalline materials to become disordered as a result of high shear mechanical processing was investigated. A data-driven model was generated from a database of critical materials properties, which were expected to correlate with the potential of a small molecule organic crystalline solid to become fully disordered by the application of mechanical energy. The model was compared with a previously published disordering model based on fundamental thermodynamic relationships. Samples of 23 crystalline solids were subjected to extensive comminution under controlled temperature conditions; powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) were used to confirm disordering. Logistic regression was used to investigate the significance of each materials property with respect to the prediction of disordering potential. Seven materials properties (glass transition temperature, melting temperature, heat of fusion, crystallographic density, Young's modulus, molar volume and attachment energy) were identified as having a significant correlation with the potential for material disordering. Stepwise multivariate logistic regression was used to further assess the correlation between disordering potential and each of the seven properties. A linear probability model based on two materials properties (glass transition temperature and molar volume) was developed for the prediction of disordering potential. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2696–2708, 2009 [ABSTRACT FROM AUTHOR]

Front Cover: Unexpected strong intrinsic fluorescence is found for a common polymer poly(N‐vinylpyrrolidone) (PVP) polymerized from a very weak fluorescent monomer. The hydrolysis of the pyrrolidone ring and the formation of secondary amine oxide lead to dramatically enhanced fluorescence (about 1000 times). Further details can be found in the article by G. S. Song, Y. N. Lin, Z. C. Zhu, H. Y. Zheng, J. P. Qiao, C. C. He, and H. L. Wang* on page 278. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the article is to investigate the contribution of calprotectin and factors in toll-like receptor 4/nuclear factor-κB/myeloid differentiation factor 88 (TLR4/NF-κB/MyD88) pathway in patients with idiopathic acute anterior uveitis (IAAU). Methods: In total, 72 patients with IAAU and 56 healthy individuals were enrolled. Serum calprotectin, TLR-4, and MyD88 were determined. Best-corrected visual acuity, uveitis activity grading, and macular thickness measured by optical coherence tomography were performed. Results: Serum calprotectin, TLR4, and MyD88 levels were higher in IAAU group than those in healthy individuals. Serum calprotectin level was positively correlated with uveitis activity grading and macular thickness. Receiver operating characteristic curve analysis showed serum calprotectin had larger area under curve than serum TLR4 and MyD88. Conclusions: The calprotectin and TLR4/NF-κB/MyD88 signal might contribute to the pathogenesis of IAAU and serum calprotectin might be a specific biomarker for the measurement of ocular inflammation in IAAU. [ABSTRACT FROM AUTHOR]