Tuning the geometric and electronic structure of the single-metal-atom catalysts via simultaneous presence of metal nanoparticles or nanoclusters (NCs) offers an alternative avenue to improving their catalytic performance. Herein, we demonstrate that the coexistence of Fe NCs in proximity to Fe single atoms on N-doped porous carbon can significantly improve the catalytic performance in aerobic oxidation of primary amines to imines using air as the oxidant. A broad spectrum of primary aromatic, heterocyclic, and aliphatic amines was efficiently and selectively oxidized into their corresponding imines in good to high yields. Experimental measurements and theoretical calculations reveal that the proximity of Fe NCs interacts with Fe single atoms, which not only benefits the adsorption of molecular O2 and amine substrates but also promotes the activation of O2 to selectively generate singlet oxygen (1O2) and then facilitates the key intermediate imine formation via H-atom abstraction with a lower energy barrier, thereby significantly boosting the reaction activity.

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Degradation of 29 dyes by means of an activated carbon fiber (ACF) electrode electrolysis system was performed successfully. Almost all dye solutions tested were decolorized effectively in this ACF electrolysis process. Internal relationships between treatment mechanisms and chemical composition of the dye have been discussed in this paper. Generally, it is shown that higher solubility leads to greater degradation in the process. Dyes with many -SO 3 − , COO − , -SO 2 NH 2 , -OH, hydrophilic groups, and azo linkages are susceptible to reduction. However, dyes with many -C=O, -NH-and aromatic groups, and hydrophobic groups, tend to be adsorbed. For dyes with -SO 3 − , -COOH and -OH groups, if their molecules linearly spread in solution and have a significant tendency to form colloids by hydrogenous bonding, they also tend to be adsorbed and flocculated. Typical dynamic electrolysis of dye Acid Red B, Vat Blue BO and Disperse Red E-4B shows how the two major mechanisms, degradation and adsorption, act differently during treatment. Reduction occurs evenly during treatment. During the dominant adsorption process, after certain amount of iron is generated, colloid precipitation occurs and TOC and color are rapidly removed.

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We have determined the nucleotide sequence alteration in the 15S rRNA gene of a Saccharomyces cerevisiae strain carrying the previously described mitochondrial ochre suppressor, MSUI. The suppressor contains an A residue at position 633 of the yeast mitochondrial sequence, in place of the wild-type G. This position, located in the highly conserved region forming the stem of the '530-loop', corresponds to G517 of the Escherichia coli 16S rRNA and is occupied by G in all other known small rRNA sequences. This finding strongly supports the previous conclusions of others that the 530-loop region plays an important role in enhancing translational accuracy.

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The PITSLRE protein kinases are parts of the large family of p34cdc2-related kinases. During apoptosis induced by some stimuli, specific PITSLRE isoforms are cleaved by caspase to produce a protein that contains the C-terminal kinase domain of the PITSLRE proteins (p110C). The p110C induces apoptosis when it is ectopically expressed in Chinese hamster ovary cells. In our study, similar induction of this p110C was observed during anoikis in NIH3T3 cells. To investigate the molecular mechanism of apoptosis mediated by p110C, we used the yeast two-hybrid system to screen a human fetal liver cDNA library and identified p21-activated kinase 1 (PAK1) as an interacting partner of p110C. The association of p110C with PAK1 was further confirmed by in vitro binding assay, in vivo coimmunoprecipitation, and confocal microscope analysis. The interaction of p110C with PAK1 occurred within the residues 210 -332 of PAK1. Neither association between p58 PITSLRE or p110 PITSLRE and PAK1 nor association between p110C and PAK2 or PAK3 was observed. Anoikis was increased and PAK1 activity was inhibited when NIH3T3 cells were transfected with p110C. Furthermore, the binding of p110C with PAK1 and inhibition of PAK1 activity were also observed during anoikis. Taken together, these data suggested that PAK1 might participate in the apoptotic pathway mediated by p110C.Apoptosis is a form of altruistic cell suicide, which is involved in many physiological processes, including tissue homeostasis, embryonic development, and immune response (1, 2). It is becoming increasingly clear that cell cycle regulators such as the p34cdc2 gene family could influence apoptosis (3-7). The PITSLRE protein kinases, which are coded by the gene localized to human chromosome 1p36.3 and a syntenic region of mouse chromosome 4, are parts of the large family of p34cdc2-related kinases (8 -14). There are at least 20 PITSLRE protein kinase isoforms, which are differentially expressed in mammalian tissues and regulate diverse cellular functions, including the cell cycle control, tumorigenesis, the regulation of RNA splicing or transcription, and so on (8, 10 -11,13-26). Studies indicated that several of the PITSLRE protein kinase isoforms might serve as effectors in apoptotic signaling pathways (15-18).During apoptosis induced by Fas or tumor necrosis factor, the action of p110C, a novel processed PITSLRE isoform resulting from the proteolysis of specific larger PITSLTR isoforms, significantly increased (15,18). Previous studies of our group and others (15,26) showed that apoptosis was increased when p110C was ectopically expressed in Chinese hamster ovary cells or SMMC 7721 hepatocarcinoma cells. These data suggested that p110C might play an important role in mediating apoptosis. In this study, we also detected the expression of p110C in NIH3T3 cells during anoikis, which is a form of apoptosis induced by the disruption of cell-matrix interaction. In agreement with the previous studies, a similar induction of p110C was observed during anoikis in NIH3T3 cells. It ...