Comparison of the Activity of a Rhodium‐Biphephos Catalyst in Thermomorphic Solvent Mixtures and Microemulsions

Tunable solvent systems provide optimal reaction conditions for homogeneous catalysis as well as appropriate conditions for separating the product from the catalyst via temperature switches. Two tunable solvent systems are presented based on different thermodynamic concepts, namely thermomorphic multicomponent solvent systems and dispersions of immiscible liquids, stabilized by nonionic surfactants as microemulsions. Both systems were applied for the regioselective hydroformylation of the model substrate 1‐dodecene with a Rhodium/ligand catalyst system. The accessibility of the catalyst for the reactants was compared between the molecularly dispersed mixtures and the colloidally dispersed microemulsion systems which are heterogeneous on the microscopic level.     

The effect of domestic processing on the content and bioaccessibility of carotenoids from chili peppers (Capsicum species)

The content and bioaccessibility of carotenoids from different chili peppers were analysed and the effects of typical domestic processing were investigated. Peppers were analysed before and after cooking by conventional boiling (10 min in 100 °C water) and also following a freezing period of four months in a domestic freezer (−20 °C). The content and bioaccessibility of the eight carotenoids quantified varied, depending on cultivar, species, colour and processing. Provitamin A carotenoids (β-carotene and β-cryptoxanthin) and capsanthin were present at highest concentrations in the samples before and after processing. In general, yellow and orange peppers were the best sources of lutein, zeaxanthin and neoxanthin. Xanthophyll carotenoids were more efficiently transferred to the micelles and, therefore, were also more bioavailable. Processing decreased the carotenoid content in certain samples; however, the micellar content was generally not lower for processed peppers; therefore the bioaccessibility of carotenoids from processed peppers is enhanced relative to unprocessed peppers.     

Immigrant-Chinese and Euro-American parents' physical closeness with young children: Themes of family relatedness.

This study examined cultural differences in the expression and meaning of physical closeness. Findings indicated that immigrant-Chinese parents, as compared with Euro-American parents, sleep in closer proximity with their children; more often view independence as children growing with the family; are more likely to emphasize the family unit; and place greater importance on inhibition of expression adherence to correct values, and hierarchy of relations. Euro-Americans, by contrast, are more accepting of nudity; place more emphasis on psychological benefit of physical closeness and on the child's expression of wants and feelings; more often view independence as celebrating the child's distinctiveness; and place greater importance on intimacy, pleasure, and spousal exclusiveness. The authors suggest that closeness is characterized by an overarching theme of harmony in immigrant-Chinese families and by an overarching theme of romance in Euro American families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gold(I) N‐Heterocyclic Carbene Complexes with Naphthalimide Ligands as Combined Thioredoxin Reductase Inhibitors and DNA Intercalators

Organometallic conjugates consisting of a gold(I) N‐heterocyclic carbene (NHC) moiety and a naphthalimide were prepared and investigated as cytotoxic agents that interact with both DNA and the disulfide reductase enzyme thioredoxin reductase (TrxR). The complexes were potent DNA intercalators related to their naphthalimide partial structure, inhibited TrxR as a consequence of the incorporation of the gold(I) moiety, and triggered efficient cytotoxic effects in MCF‐7 breast and HT‐29 colon adenocarcinoma cells. Strong effects on tumor cell metabolism were noted for the most cytotoxic complex, chlorido[1‐(3′‐(4′′‐ethylthio‐1′′,8′′‐naphthalimid‐N′′‐yl))‐propyl‐3‐methyl‐imidazol‐2‐ylidene]gold(I) ( 4 d ). In conclusion, the conjugation of naphthalimides with gold(I) NHC moieties provided a useful strategy for the design of bioorganometallic anticancer agents with multiple modes of action.     

In vitro and in vivo investigations of upconversion and NIR emitting Gd2O3:Er3+,Yb3+ nanostructures for biomedical applications

The use of an “over 1000-nm near-infrared (NIR) in vivo fluorescence bioimaging” system based on lanthanide containing inorganic nanostructures emitting in the visible and NIR range under 980-nm excitation is proposed. It may overcome problems of currently used biomarkers including color fading, phototoxicity and scattering. Gd₂O₃:Er³⁺,Yb³⁺ nanoparticles and nanorods showing upconversion and NIR emission are synthesized and their cytotoxic behavior is investigated by incubation with B-cell hybridomas and macrophages. Surface modification with PEG-b-PAAc provides the necessary chemical durability reducing the release of toxic Gd³⁺ ions. NIR fluorescence microscopy is used to investigate the suitability of the nanostructures as NIR–NIR biomarkers. The in vitro uptake of bare and modified nanostructures by macrophages is investigated by confocal laser scanning microscopy. In vivo investigations revealed nanostructures in liver, lung, kidneys and spleen a few hours after injection into mice, while most of the nanostructures have been removed from the body after 24?h.