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Solar-driven CO2 with H2O conversion into valuable chemical fuels has attracted considerable attention. However, the low separation efficiency of photogenerated carriers and deficient surface-active sites on catalysts result in low CO2 reduction activity. Herein, the bulk Bi2O2(OH)-(NO3) material was exfoliated to atomically thin nanosheets for shortening the migration distance of photoinduced carriers and enlarging the specific surface area. Photoreduction CO2 test results showed that the CO yield of nanosheets could be enhanced up to nearly six times compared to that of the bulk catalyst. Moreover, a series of ultrathin Bi2O2(OH)1+x(NO3)1–x nanosheets were constructed based on the surface regulation of the OH– concentration on ultrathin nanosheets. The optimized catalyst had an elevated CO yield of 16.7 μmol/g after irradiation for 3 h, about 10 times higher than that of the bulk catalyst. Further theoretical calculations revealed that the superficial NO3– has stronger charge accumulation/depletion behavior with the adjacent Bi atom than surface OH–, conducive to the transfer of photogenerated charge from the bulk phase to the catalyst surface. This work may provide a powerful strategy for the design of a surface-controlled 2D ultrathin photocatalyst for efficient CO2 reduction. [ABSTRACT FROM AUTHOR]

Three novel dodecamanganese(III) clusters containing phosphonate ligands [Mn(sub 12)O(sub 8)(O(sub 2)CR)(sub 6)(O(sub 3)PC(sub 6)H(sub 9)(sub 7)(L)(sub 3)] (R = Me, Ph; L = 2,2'-biby, 1,10-phen) are synthesized. They have similar Mn(sub 12) cores with a new type of topologic structure.

Raman results are presented for Cu2O2 systems in which the spectroscopic features of the side-on peroxo-dicopper(II)/bis-mu-oxo-dicopper(III) equilibrium which are electronically, rather than sterically, controlled. The studies define the effects of endogenous donor strength on Cu-O and O-O bonds.

Research has been conducted on the copper(I)-acetonitrile complexes. The synthesis of the two-coordinate copper(I) compound ligated by nitrile ligands has been carried out and the results indicate that use of this compound for copper(I) complex synthesis can lead to solubility in low-dielectric solvents.

The amino terminus of the human D4 receptor was investigated for its cryptic initiation site in the first transmembrane region. Deletion of this amino terminus did not prevent expression, which continued to express up to 70% of the D4 control levels. This evidence supports an alternative site for translation initiation in the transmembrane region, hypothesized to be at nucleotide +112. Possible role of the amino terminus is stabilizing the active site for the functional activity of the receptor.

Rabbit uterine and chick oviduct cytosols are used to separate FKBP59 as a big compound with hsp90, hsp70 and RP when it is bound with the immunosuppressant. The immune system is not the only domain of the connection between immunophilin, heat shock proteins and steroid receptors. The process of evolution reveals the conservation of the reaction between immunophilins and heat shock proteins, which shows a yeast FKBP59 homologue complexed with hsp70 and hsp90. The FKBP59 and heat shock protein complex reveal the presence of actin and a new protein, p63.

Three-dimensional ordered macroporous (3DOM) metal-oxide-based materials have received much attention in the field of gas sensing for their potential in breath acetone analysis. The major challenge of metal-oxide-based sensors for analyzing acetone from exhalation is their poor selectivity in the complex mixture of breath. Functionalizing of sensitive materials by noble metal nanoparticles (NPs) is one of the efficient methods to improve gas sensing selectivity, but noble metal NPs are prone to aggregation at the working temperature. To address these issues, we herein have constructed a series of AuPd/WO3 materials by depositing bimetallic AuPd alloy NPs on the surface of 3DOM WO3 supports. The amount of AuPd NP content and Au/Pd molar ratio are optimized on the basis of acetone responses. The sensor based on the optimal AuPd alloy NP-decorated 3DOM WO3 (AuPdW) exhibits high responses to trace acetone with rapid response/recovery speeds. Besides, the AuPdW sensor presents excellent acetone selectivity and good reproducibility. More attractively, the responses of the sensor to acetone exhibit no noticeable decline over 8 weeks, indicating good long-term stability of the synthesized material. We suggest that the improved responses and excellent selectivity to acetone are ascribed to the synergistic effect of electronic sensitization and chemical sensitization of AuPd alloy NPs. The good long-term stability of AuPdW is attributed to the steric hindrance effect of 3DOM structure to AuPd NPs. [ABSTRACT FROM AUTHOR]

The novel complex [Mn(bpe)(H2O)4]0.5n(tp)0.5n(bpe)n was structurally characterized. The solid-state structure of the complex spread out through hydrogen bonds of aqua ligands with tp counterdianions and packing bpe ligands. The manganese atom of the asymmetric unit lay on the crystallographic inversion center and the geometry around the manganese(II) ion was octahedral with a large tetragonal elongation. All of the bpe adopted anticonformation showing the separation between pyridyl ring planes.

2-Silyldihydropyrans and 2-silyldihydrofurans are synthesized from (gamma-haloacyl)- and (delta-haloacyl)-silanes. The acylsilanes are allowed to undergo a cyclization reaction in a polar aprotic solvent producing good yields of the furan and payran derivatives. The cyclization reaction also allows for substitution at the carbon 2 and carbon 3 positions making molecular manipulations possible. Olefins and carbocations can likewise promote this novel cyclization reaction.

The different electronic effects on the formation and subsequent reactivity of dioxygen adducts of copper(I) complexes with tridentate ligands are reported. The product, [{Cu(R-MePY2)}(sub 2)(O2)](B(C6F5)(sub 4))(sub 2), (2(super R)), (2(super Me2N)) exhibits exceptionally high reactivity towards newly examined and interesting exogenous substrates like tetrshydrofuran and N,N'-dimethylaniline.

The kinetics of O2-binding to a series of dicopper(I) complexes [Cu2(Nn)(MeCn)2](super 2+) (1(super Nn) (-(Ch2)(sub n) - (n= 3-5) linked bis [(2-(2-pyridyl)ethyl]amine, PY2) and their close mononuclear analogue, [(MePY2)Cu(MeCN)](super +), which form peroxo-bridged dicopper(II) adducts is presented. The results indicate that the reactions of [Cu2(Nn)(MeCn)2](super 2+) (1super Nn) with O2 in dichloromethane occur with rapid formation of intramolecular (Mu)-peroxo species.

Research has been conducted on the copper-dioxygen interactions. The chemistry of the copper(I) tridentate ligand complexes has been investigated and the results are reported.

Gene therapy has received considerable attention due to its great potential in the treatment of various diseases; however, the design of efficient and biocompatible carriers for the delivery of siRNA as well as DNA still remains a major challenge. In this study, we developed an efficient carrier for gene delivery by modification of a compound containing both guanidyl and phenyl groups on the surface of a cationic dendrimer. The guanidyl group on the dendrimer facilitates nucleic acid condensation via specific guanidinium-phosphate interactions, whereas the phenyl group on the polymer is critical for efficient endosomal escape. The combination of guanidyl and phenyl shows a synergistic effect in facilitated endocytosis. The designed material is much more efficient in siRNA and DNA delivery than control materials such as dendrimers engineered with a guanidyl or phenyl group only, as well as intact dendrimers, and shows comparable efficacy to commercial transfection reagent Lipofectamine 2000. In addition, the material and its complex with nucleic acid show minimal toxicity on the transfected cells. This study provides a new strategy to develop multifunctional polymers for efficient siRNA and DNA delivery. [ABSTRACT FROM AUTHOR]

The efficient delivery of biopharmaceutical drugs such as proteins and peptides into the cytosol of target cells poses substantial challenges owing to their large size and susceptibility to degradation. Current protein delivery vehicles have limitations such as the need for protein modification, insufficient delivery of large-size proteins or small peptides, and loss of protein function after the delivery. Here, we adopted a rational approach to design a polymer with robust efficacy for intracellular protein and peptide delivery. The polymer is composed of a dendrimer scaffold, a hydrophobic membrane-disruptive region, and a multivalent protein binding surface. It allows efficient protein/peptide binding, endocytosis, and endosomal disruption and is capable of efficiently delivering various biomacromolecules including bovine serum albumin, R-phycoerythrin, p53, saporin, β-galactosidase, and peptides into the cytosol of living cells. Transduction of apoptotic proteins and peptides successfully induces apoptosis in cancer cells, suggesting that the activities of proteins and peptides are maintained during the delivery. This technology represents an efficient and useful tool for intracellular protein and peptide delivery and has broad applicability for basic research and clinical applications. [ABSTRACT FROM AUTHOR]