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Biomimics for the active site of [FeFe]-hydrogenases, have been synthesized and characterized. Treatment of [Fe2(CO)6{μ-SCH2CH(CH3)S}] (1) and phosphine ligands tris(2-furyl)phosphine, tri(m-tolyl)phosphine, bis(diphenylphosphino)methane (dppm), or 1,2-bis(diphenylphosphino)benzene (dppbz) with Me3NO·2H2O as the decarbonylation agent afforded the corresponding phosphine-containing derivatives [Fe2(CO)5(L){μ-SCH2CH(CH3)S}] (L = P(2-C4H3O)3, 2; P(3-C6H4CH3)3, 3; Ph2PCH2PPh2, 4) and [Fe2(CO)4{κ2-(Ph2P)2(1,2-C6H4)}{μ-SCH2CH(CH3)S}] (5) in moderate to good yields. The new complexes 2‒5 have been structurally characterized by elemental analysis, IR, NMR spectroscopy, and further confirmed by X-ray diffraction analysis. The electrochemistry of complexes 2‒5 have been investigated by cyclic voltammetry, showing that they can catalyze the reduction of protons to H2 in the presence of HOAc.

The porous carbon-coated LiFePO4 (LFP) nanocrystals synthesized by in situ plasma-assisted pyrolysis are reported. The particle size of LFP nanoparticles is well controlled through the coating of polyaniline (PANI) on FePO4. The effect of PANI content in FePO4/PANI on the morphology and electrochemical performance of LiFePO4 particles is extensively investigated. Results show that the optimized amount of PANI in FePO4/PANI is 10.16% and the corresponding carbon content in activated porous carbon-coated LiFePO4 (LFP/AC-P4) is 9.27%. The primary particle size of LFP/AC-P4 is 20~50 nm which are wrapped and connected homogeneously and loosely by activated porous carbon. The LFP/AC-P4 composite delivers a capacity of 166.9 mAh g−1 at 0.2 C, which is much higher than carbon-encapsulated LiFePO4 nanocomposite (LFP/C) synthesized without the assistance of plasma pyrolysis (163.5 mAh g−1). Even at high rate of 5 C, a specific capacity of 128.4 mAh g−1 is achievable with no obvious capacity fading after 250 cycles.

The hydrothermal reaction of cobalt salt in the presence of 4-pyridyl-tetrathiafulvalene-4-pyridyl (4-py-TTF-4-py) and terephthalic acid (PTA) has been employed for the preparation of a novel metal–organic framework (MOF), i.e., (4-py-TTF-4-py)2M2(PTA)4 (M = Co2+). The obtained MOF is then used as a starting material for the synthesis of Co nanoparticles embedded in N,S-codoped carbon layer and supported on multi-walled carbon nanotubes (Co@NSC/MWCNTs) through the high-temperature calcination. Specifically, the calcination leads to the formation of N,S-codoped carbon-coated Co nanoparticles with simultaneous growth on the MWCNTs due to decomposition of the MOF. When used as the electrocatalyst, the Co@NSC/MWCNTs are found to have a higher activity for the oxygen reduction reaction (ORR) and follow a four-electron pathway. The catalytic activity of the Co@NSC/MWCNTs is much higher than that of the pure MWCNTs and the MOFs/MWCNTs. Although the Co@NSC/MWCNTs still exhibit slightly higher overpotential for the ORR, it is indeed more kinetically facile than the commercial Pt/C catalyst, as demonstrated by its higher limiting current density and lower Tafel slope. Additionally, the Co@NSC/MWCNTs also show superior stability and better tolerance to methanol crossover and CO poisoning, compared with those of the commercial Pt/C catalyst. These results strongly suggest that the Co@NSC/MWCNTs could be used as one of the most promising ORR electrocatalysts for the ORR with great potential to replace the Pt/C. The work present here opens up a new route for the design of carbon-integrated ORR electrocatalysts with high performance from a great number of available and yet rapidly growing MOFs.

The micrometer-sized ZnCo2O4 parallelepipeds with a hierarchical porous structure have been fabricated by a simple two-step procedure, i.e., the synthesis of the Zn1/3Co2/3CO3 parallelepipeds and the subsequent calcination. When tested in lithium-ion batteries (LIBs), the hierarchical porous ZnCo2O4 parallelepipeds could exhibit a reversible capacity of >860 mAh g−1 at a current density of 0.1 C. This clearly demonstrates the potential use of the hierarchical porous ZnCo2O4 parallelepipeds in LIBs. The high electrochemical performance of the hierarchical porous ZnCo2O4 parallelepipeds might originate from the unique porous structure which consists of the secondary ZnCo2O4 particles. First, the porous structure allows for a better accessibility of the active material to the Li+ ion storage, favoring easier diffusion of electrolyte in and out of electrode material. Second, the presence of the secondary particles shortens a pathway of Li+ diffusion in ZnCo2O4, facilitating the better utilization of the active material.

To explore how the sentence contexts affect self-positivity bias, we presented the participants with negation and affirmation sentences. Each sentence was ended with an adjective word describing human being's personality. The participants were asked to judge whether the sentences correctly described their own personalities. In affirmation sentences, the behavioral data showed that self-positivity bias occurred when participants considered the sentences to be in accordance with their personality; the ERP data showed that P200 amplitude was consistent with this behavioral result. In negation sentences, behavioral data showed self-positivity bias, regardless of whether the sentences were in accordance with participants' personality or not. However, the self-positivity bias was not observed in the ERP results from negation sentence. In summary, sentence type modulated the effect of self-positivity bias. The reason could be that processing affirmation and negation sentences requires different amount of cognitive resources.

The purpose of this study was to explore the effects of emotions in conflict processing. Behavioral and event related potential (ERP) data were acquired from twenty participants while they were performing a color-flanker task, in which the stimuli were emotional and neutral words. Through temporal principal component analysis (PCA) of ERP, three PCA components were extracted with their time windows mapped to three ERP components: N1, N2 and P3. Further analysis revealed, when the stimuli were the positive words, N1 was marginally greater for the congruent condition than for the incongruent condition (p = .06); while the stimuli were the negative words, N1 was greater for the incongruent condition than for the congruent condition (p = .02); however, no significant interaction effect involving the valence of words (positive vs. negative) and the color congruency (congruent vs. incongruent) was found on N2, P3 and the behavior data. The result suggested that negative emotion might lead to more attention allocation in the incongruent processing, while positive emotion might lead to more attention allocation in the congruent processing. Furthermore, ERP source analysis in the present study confirmed anterior cingulate cortex was involved in the conflict monitoring mechanism.

A non-hemorrhagic, chymotrypsin-like serine protease, UFEII, was purified from the marine echiuroid worm, Urechis unicinctus, after a combination of chromatography steps. UFEII was monomeric, with an apparent molecular weight of 26.7 kDa via SDS-PAGE. The isoelectric point of UFEII was 4.03, and the maximum activity of the enzyme was observed at 50 °C and pH 8.0. According to fibrin plate assays, UFEII could not only directly degrade fibrin and fibrinogen but also activate plasminogen. Further, UFEII preferentially hydrolyzed the fibrinogen γ-chain, followed by the Bβ-chains and Aα-chains. Moreover, ufeII, full length of the gene encoding UFEII, was obtained by RT-PCR, degenerated PCR, and nested PCR. The ufeII was determined to be a 906-bp cDNA containing an open reading frame of 795 bp encoding a putative protein of 264 amino acids with a predicted molecular weight of 27.03 kDa. Besides, UFEII exhibited no hemorrhagic effect. Overall, U. unicinctus may represent a potential source of new therapeutic agents in thrombolytic therapy.

A new serine protease with fibrinolytic activity from a marine invertebrate, Urechis unicinctus, was purified to electrophoretic homogeneity using column chromatography. SDS-PAGE of the purified enzyme showed a single polypeptide chain with MW ~20.8 kDa. Its N-terminal sequence was IIGGSQAAITSY. The purified enzyme, UFEIII, was stable at pH 6-10 below 60 °C with an optimum pH of 8.5 at approx. 55 °C. The enzyme activity was significantly inhibited by PMSF and SBTI suggesting that it was a serine protease. In fibrin plate assays, UFEIII was contained 1.46 × 10(3 )U (urokinase units) mg(-1) total fibrinolytic activity, which consisted of 692 U mg(-1) direct fibrinolytic activity and 769 U mg(-1) plasminogen-activator activity. Km and Vmax values for azocasein were 1 mg ml(-1) and 43 μg min(-1) ml(-1), respectively.

OBJECTIVE The aim of the present study was to determine the expression of vascular endothelial growth factor (VEGF) and its receptor, kinase insert domain containing receptor (KDR), and their significance in regulating tumor angiogenesis in the early stages of cervical cancer. METHODS Using the immunohistochemical SP method, the expression of VEGF and KDR was determined in the cancer cells. In addition, the microvessel density (MVD), labeled by CD34 in the tumor stroma, was examined in 18 cases of cervical intraepithelial neoplasms (ClN), 75 cases of early invasive cervix carcinomas (ICC) and 15 specimens of normal cervical epithelium (NCE). RESULTS In ICC cases, VEGF and KDR were mainly expressed in the cellular membrane and/or cytoplasm of tumor cells, while expression of CD34 was found mainly in the vascular epithelial cells of the tumor stroma. The positive expression rate of VEGF and KDR, and the MVD increased remarkably from NCE through CIN to ICC (P