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A molecular-level mechanism of alkali induced konjac glucomannan (KGM) hydrogel gelation processing is considered with the application of nuclear magnetic resonance (NMR) spectroscopy and atomic force microscopy (AFM) as complementary methods to diffusive wave spectroscopy (DWS) microrheology and thermoanalysis. It is shown that deacetylation of KGM chains occurs immediately upon mixing with Na 2 CO 3 , inducing self-packaging. Partial unfolding of the packed loose structure of dehydrated KGM is observed upon heating. The configuration transition from random coils to self-assembling filament networks takes place before KGM aggregating to form large irreversible bundles with a lower degree of cross-linking. The gelation is not fulfilled until the temperature is increased to above 70 °C when the significant agglomeration is initiated among transitional fibrils to form junction zones essentially composed of acetyl-free portions. This suggests the intermolecular aggregation of KGM chains not simply regarding to hydrogen bonds, but essentially relating to hydrophobic interactions. [ABSTRACT FROM AUTHOR]

Driven by the association of chemical weak forces and solvent effects, zero- to two-dimensional nanostructures of thiophene-substituted perylene bisimide such as spheres and blocky structures were obtained. Light-controlled intramolecular charge transfer from the trithiophene unit to the perylene bisimide in the solid state can induce a hypochromatic shift and enhanced fluorescent emission. [ABSTRACT FROM AUTHOR]

A series of triazolecarboxamide-containing foldamers were synthesized from simple starting materials by means of repeated [3+2] cycloadditions) and acid-amine coupling reactions. Foldamer-anion binding behavior and affinities were determined by 1H NMR titration in [D2]dichloromethane. The selective recognition of sulfate by these motifs was studied by one- and two-dimensional (1H, 1H-1H COSY and NOESY) NMR spectroscopy as well as UV/Visible and fluorescence titrations. The structures of the triazolecarboxamide-containing foldamers can be optimized for highly selective recognition of sulfate anions by changing the numbers of triazolecarboxamide units and by the introduction of electron-withdrawing substituents on the terminal benzene ring. These findings indicate the importance of the structural compatibility between the receptor and anions for the highly selective anion binding as well as the electronic effect on tuning the anion-binding affinities of receptors. [ABSTRACT FROM AUTHOR]

Abstract: Aims: This paper is aimed to develop and validate the hypertension scale of the system of Quality of Life Instruments for Chronic Diseases, QLICD-HY. Methods: The QLICD-HY instrument was developed based on programmed decision procedures with multiple nominal and focus group discussions and pilot testing. A total of 157 inpatients with hypertension were used to provide the data measuring QOL three times before and after treatment. The psychometric properties of the scale were evaluated with respect to validity, reliability and responsiveness employing correlation and factor analyses, and t-tests. Results: Correlation and factor analyses confirmed good construct validity and criterion-related validity when using Short Form (36) Health Survey (SF-36) as a criterion. Test–retest reliability coefficients (Pearson r and intra-class correlation (ICC)) for the overall instrument score and all domains except for the hypertension-specific domain (SPD) (0.75) were higher than 0.80 with a range of 0.75–0.91; the internal consistency α for all domains except for the hypertension-specific domain (0.66) was higher than 0.70. The overall score and scores for most facets within each domain except for the social domain (SOD) had statistically significant changes (t-tests) after treatment with moderate effect sizes. Conclusion: QLICD-HY has good validity, reliability, responsiveness and can be used as the quality-of-life instrument for patients with hypertension. [Copyright &y& Elsevier]

Abstract: A series of anthracenyl(anthraquinonyl)-substituted difluoroboron dipyrromethene dyes were synthesized through a Suzuki cross-coupling reaction. The crystal structure combined with geometric optimization reveals a moderate dihedral angle between the anthracenyl(anthraquinonyl) plane and the connected pyrrolyl plane. Photophysical characterization shows that the introduction of anthracenyl(anthraquinonyl) moiety to the BODIPY core effectively tunes the emission properties of BODIPY while retaining the separate absorption properties of BODIPY and anthracene(anthraquinone). High fluorescent quantum yields of up to 0.70 and a large Stokes shift (ca. 1707 cm−1) were noted. Electrochemical characterization suggests that the anthracenyl(anthraquinonyl) linkage and BODIPY unit lead to rich and tunable potentials. TD-DFT calculation proved a moderate intramolecular charge-transfer process between the BODIPY core and anthracenyl(anthraquinonyl) moiety. [Copyright &y& Elsevier]

Amino-substituted pyrrole-fused perylenebis(dicarboximides) have been prepared from tri- or tetrabromoperylene prcursors by using the classical azidation conditions for the substitution of aromatic halogen, that is, NaN3, sodium ascorbate, CuI, and N, N-dimethylethane-1,2-diamine in DMSO/H2O. The pyrrole-fused dyes are highly photochemically and thermally stable, which may be useful for labelling and as building blocks for the synthesis of functional molecular materials. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Our goal was to develop a self-administered quality of life scale for patients with drug addiction/dependence (QOL-DA) and compare it with the SF-36 and the WHOQOL-100. Methods: Employing theory and methodology of rating scale construction, a self-administered quality of life instrument for individuals with drug dependence QOL-DA was developed and evaluated utilizing responses from 212 drug-dependent subjects at the Kunming Municipal Mandatory Detoxification and Rehabilitation Center in China. Quality of life was measured using the SF-36, WHOQOL-100 and QOL-DA three times during the detoxification. Results: Test–retest reliability in the domains of physical function, psychological function, social function and toxicity were 0.82, 0.64, 0.78, and 0.76, respectively. Cronbach''s coefficient α for the 4 domains was 0.87, 0.89, 0.93 and 0.86, respectively. Correlations and factor analysis showed good construct validity. Criterion-related and convergent validity was confirmed by using the SF-36 and the WHOQOL-100 simultaneously. The instrument does show the change in QOL after two weeks of detoxification with higher standardized response mean higher than that of SF-36 and WHOQOL-100. Conclusion: The instrument developed has good validity, reliability and better responsiveness than instruments currently used, and can be employed effectively to measure the quality of life of individuals with drug dependence. [Copyright &y& Elsevier]

Indoles are essential heterocycles in medicinal chemistry, and therefore, novel and efficient approaches to their synthesis are in high demand. Among indoles, 2‐aryl indoles have been described as privileged scaffolds. Advanced herein is a straightforward, practical, and transition‐metal‐free assembly of 2‐aryl indoles. Simply combining readily available 2‐fluorotoluenes, nitriles, LiN(SiMe3)2, and CsF enables the generation of a diverse array of indoles (38 examples, 48–92 % yield). A range of substituents can be introduced into each position of the indole backbone (C4 to C7, and aryl groups at C2), providing handles for further elaboration. [ABSTRACT FROM AUTHOR]

Indoles are essential heterocycles in medicinal chemistry, and therefore, novel and efficient approaches to their synthesis are in high demand. Among indoles, 2‐aryl indoles have been described as privileged scaffolds. Advanced herein is a straightforward, practical, and transition‐metal‐free assembly of 2‐aryl indoles. Simply combining readily available 2‐fluorotoluenes, nitriles, LiN(SiMe3)2, and CsF enables the generation of a diverse array of indoles (38 examples, 48–92 % yield). A range of substituents can be introduced into each position of the indole backbone (C4 to C7, and aryl groups at C2), providing handles for further elaboration. [ABSTRACT FROM AUTHOR]

The construction of efficient synthetic functional receptors with tunable cavities, and the self-organization of guest molecules within these cavities through noncovalent interactions can be challenging. Here we have prepared a double-cavity molecular cup based on hexaethynylbenzene that possesses a highly π-conjugated interior for the binding of electron-rich guests. X-ray crystallography, NMR spectroscopy, UV/Vis spectroscopy, fluorescent spectroscopy, cyclic voltammetry, and SEM were used to investigate the structures and the binding behaviors. The results indicated that the binding of a guest in one cavity would affect the binding of the same or another guest in the other cavity. The effect of electron transfer in this system suggests ample opportunities for tuning the optical and electronic properties of the molecular cup and the encapsulated guest. The encapsulation of different guests would also lead to different aggregate nanostructures, which is a new way to tune their supramolecular architectures. [ABSTRACT FROM AUTHOR]

Highlights: [•] A series of furan-substituted perylene diimide derivatives were synthesized. [•] An efficient supramolecular architecture approach was demonstrated. [•] Studies indicate the micro-rods displayed interesting optical waveguide behavior. [ABSTRACT FROM AUTHOR]

A perylenetetracarboxdiimide derivative containing an anthraquinone unit has been synthesized by the phototriggered intramolecular cyclization of 2-anthraquinone-substituted perylenetetracarboxdiimide. The anthraquinone-substituted perylenetetracarboxdiimide dyes showed excellent electron-accepting abilities with four reversible reduction potentials. Photovoltaic devices of ITO/PEDOT:PSS/P3HT:PDIs/Ca/Al were fabricated and power conversion efficiencies of 0.16 and 0.39 were obtained for 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

The synthesis of 1,10-dihydroxyperylene bisimides by nucleophilic substitution of brominated perylene bisimide is described. 1,10-Dihydroxyperylene bisimides formed J aggregates in nonpolar solvents and showed a clearly redshifted absorption band. The solvent polarity also influenced the hydrogen bond with the hydroxyl group, and thus, the photophysical properties of perylene bisimide. The photophysical properties of these dihydroxyperylene perylene bisimides can also be tuned by changing charge transfer from the hydroxyl groups to the perylene core through the introduction of metal ions. [ABSTRACT FROM AUTHOR]

Abstract: Because the excreted sporocysts and/or oocysts of various species of Sarcocystis may not be discriminated morphologically, we sought to validate a diagnostic technique based on variation in the 18S rDNA sequence. Oocysts and/or sporocysts from three taxa of Sarcocystis were collected from human, feline, and canine definitive hosts that had fed upon meats infected with the muscle cysts of Sarcocystis hominis, Sarcocystis fusiformis and a species of Sarcocystis from water buffalo that could not be distinguished from Sarcocystis cruzi. Using a new collection method employing filter paper, these excreted oocysts and sporocysts were subjected to DNA extraction, as were the corresponding muscle cysts. Methods employing PCR–RFLP and DNA sequencing of a partial 18S rDNA gene (ssrRNA) sequence were then used to successfully distinguish among the three taxa. The same, unique restriction digestion pattern characterizes the tissue cysts and oocysts and/or sporocysts of each parasite taxon. The technique makes possible amplification and identification of species specific gene sequences based on DNA extracted from as few as 7 excreted sporocysts (the equivalent of 3 and 1/2 oocysts) from freshly prepared material, or as few as 50 sporocysts from feces samples that had been stored in potassium dichromate (K2Cr2O7) for as long as 6 years. This represents the first report using molecular diagnostic procedures to diagnose oocysts of Sarcocystis in faecal samples, describing a valuable new tool for studying the epidemiology of various Sarcocystis species. [Copyright &y& Elsevier]