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Previous studies have found that self-awareness can help people to recruit more cognitive resources, while people with more cognitive resources can better buffer the detrimental effects of negative events. However, it is not clear whether self-awareness can directly buffer the consequences of negative feedback (i.e., reducing neural sensitivity to negative feedback). To explore this issue, we used a scrambled sentence task (SST) to manipulate participants' self-awareness (self vs. other) and investigated whether outcome evaluations in a gambling task are modulated by the self-awareness priming. Event-related brain potentials (ERPs) were recorded while 27 normal adults performed a gambling task. The ERP analysis focused on the feedback-related negativity (FRN), reward positivity (RewP) and P300 component. We found that the self-awareness priming resulted in a smaller FRN response to the losses compared with the other-awareness priming. There was no significant difference in the RewP response to wins between the self-awareness condition and the other-awareness condition. We also found that the self-awareness condition evoked larger P300 amplitude than the other-awareness condition. The present findings suggest that self-awareness can help people to cope with negative feedback in the early semiautomatic outcome evaluation stage (i.e., reducing neural sensitivity to negative feedback) and enhance top-down evaluation to both positive and negative feedback in the late and deliberate stage, providing direct evidence of the adaptive function of self-awareness on outcome experience.

Timetable optimization for urban subways is aimed at improving the transportation service. In congested subway systems, the effects of crowding at stations and inside the vehicles have not been properly addressed in timetabling. Moreover, it is difficult to show the time of values in different riding conditions. In this paper, we consider the passenger-travel process as a physical activity expending energy and formulate a travel energy expenditure function for a heavily congested urban subway corridor. A timetable optimization model is proposed to minimize the total energy expenditure, including waiting on the platform and travelling in the vehicle. We develop a heuristic generic algorithm to solve the optimization problem through a special binary coding method. The model is applied to the Yi-zhuang line in the Beijing subway system to obtain a passenger-oriented energy-minimizing timetable. Compared with using the existing timetable, we find a 20% reduction in average energy expenditure per passenger and a RMB 47,500 increase in social profits as the result of the timetable optimization.

In China, researchers have translated and validated several scales to measure victimization behavior. The aim of the present study was to validate the Chinese version of the victimization subscale of the Revised Peer Experiences Questionnaire (RPEQ) among primary school students. Primary school students aged between 8 and 13 years old (n = 1048) were asked to complete the Chinese version of the victimization subscale of the RPEQ and related scales. We examined internal consistency and the factor structure using confirmatory factor analysis (CFA). Depression, peer relationship, and sleep scales were used to measure construct validity. The CFA results suggested that the four-factor model had a good model fit. The results indicated that internal reliability was good (Cronbach’s α = 0.83). Construct validity was mostly supported by scores on the Chinese version of the victimization subscale of the RPEQ that strongly and positively correlated with depression and negatively correlated with peer relationship and sleep quality. The present study indicated that the Chinese version of the victimization subscale of the RPEQ has adequate reliability and validity for measuring bullying problems among Chinese primary school students.

This study was conducted to investigate the effect of N,N-diethyldithiocarbamate (DEDTC) on the changes of inflammatory cytokines after focal cerebral ischemia-reperfusion injury in rats and to explore the potential mechanism. Two hundred Sprague Dawley male rats were randomly divided into sham group, middle cerebral artery occlusion (MCAO) group and DEDTC (Zn chelator) treated group. MCAO model was established by the suture method. Rats were sacrificed at 6, 12 and 24 h after reperfusion. 2,3,5-Triphenyltetrazolium chloride (TTC) was conducted to measure the brain infarct volume. Newport Green was adopted to detect the chelatable zinc in the cerebral penumbra. Enzyme linked immunosorbent assay(ELISA) was performed to determine the release of TNF-α and IL-6. Furthermore Western blot was used to analyze the expression of the PI3K/Akt/NF-κB signaling pathway. The results showed that DEDTC resulted in a significant reduction of brain infarct volume and an obvious improvement of neurological function compared to the model group. DEDTC also decreased the release of inflammatory cytokines such as TNF-α and IL-6. The activation of PI3K/Akt/NF-κB signaling pathway induced by I/R injury was drastically inhibited by the treatment with DEDTC. In conclusion, DEDTC could protect the brain against ischemic injury induced by MCAO, which might be relevant to the inhibition of PI3K/Akt/NF-κB signaling pathway, and the decreased release of inflammatory cytokines.

In this paper, we are concerned with model-free control of the Lorenz chaotic system, where only the online input and output are available while the mathematic model of the system is unknown. The problem is formulated from an optimal control perspective and solved using an iterative method. The convergence of the iteration and the stability of the control law are proven in theory. Simulations validate theoretical conclusions and demonstrate the effectiveness of the proposed method.

7′-Hydroxyriccardin C (1) and marchantin E (2), two macrocyclic bisbibenzyls with a stereogenic center at the ethylene bridge from Chinese liverworts, were investigated stereochemically. Compound 1 was found to be optically active and occurred as a pair of dynamically interchangeable atropisomers at room temperature due to the low barrier of rotation around the biaryl bond, while 2 was a racemic mixture, which was successfully resolved by chiral HPLC into two enantiomers. Their absolute configurations were unequivocally assigned by analysis of temperature-dependent NMR spectra, X-ray crystallographic diffraction, and comparison of experimental and calculated ECD data.

The widespread use of insecticides has caused the resurgence of the brown planthopper, Nilaparvata lugens, in Asia. In this study, we investigated an organo-phosphorous insecticide, triazophos, and its ability to induce gene expression variation in female N. lugens nymphs just before emergence. By using the suppression subtractive hybridization method, a triazophos-induced cDNA library was constructed. In total, 402 differentially expressed cDNA clones were obtained. Real-time qPCR analysis confirmed that triazophos up-regulated the expression of six candidate genes at the transcript level in nymphs on day 3 of the 5th instar. These genes encode N. lugens vitellogenin, bystin, multidrug resistance protein (MRP), purine nucleoside phosphorylase (PNP), pyrroline-5-carboxylate reductase (P5CR) and carboxylesterase. Our results imply that the up-regulation of these genes may be involved in the induction of N. lugens female reproduction or resistance to insecticides.

The mechanisms of magnetic exchange interactions in two heterobridged mu-hydroxyl-mu-X dicopper complexes A and B (X = azaindole for A and X = pyrazole for B) are investigated by the calculations based on density functional theory combined with the broken-symmetry approach (DFT-BS). It is found that although the coordination circumstances of the copper centers in the two complexes are very similar, the magnetic magnitudes and signs are diametrically opposed. By the theoretical analyses of magnetic orbital interaction and spin distribution, it is indicated that the difference between the magnetic properties of the two complexes is due to the distinction of orbital interaction of two bridge ligands. Namely, the weak ferromagnetic coupling for complex A arises from the orbital countercomplementarity of the hydroxo and azaindole bridges while the strong antiferromagnetic coupling for complex B arises from the orbital complementarity of the hydroxo and pyrazolato bridges.

To compare the transition states of para-substituted phenols with that of catechol, we employed the B3LYP/6−311+G(d,p) method to calculate the energy profiles, the geometries, the spin density distributions, and other physico-chemical parameters. A comparison between catechol and para-substituted phenols indicates that their transition state geometries for hydrogen atom abstraction are similar. Substituent effects on the transition states of o-substituted phenols may differ from those of p-substituted ones. The calculated value of Ea for catechol is much lower than that of phenol, which arises mainly from the electron-donating property of the ortho-hydroxyl group. Although, the intramolecular hydrogen bond (IHB) effect on Ea is small, the IHB effect on the transition state geometry is fairly strong. According to the regression equation of the relative O−H bond dissociation enthalpy (BDE) versus values of Ea for p-substituted monophenols, the relative O−H BDE of catechol is −8.28 kcal mol−1, which is in agreement with the value obtained through a kinetic analysis (−7.2 kcal mol−1). The values of Ea are governed by resonance effects, which is similar to the observation found for the O−H BDEs. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

The title aza-Wittig reaction has been studied theoretically by means of ab initio calculations. Geometries were optimized at the HF/6-31G ∗∗ level, and single-point energy calculations were performed at the MP2/6-31G ∗∗ level using the HF/6-31G ∗∗ structures. Calculated results show that two transition states exist on the aza-Wittig reaction surface and that both the first and second forward barriers decrease in the order Cl>H>CH 3 . It can be seen that the substituent effect makes the aza-Wittig reaction for X=CH 3 and H more favorable than for X=Cl.

[reaction: see text] Bond dissociation enthalpies (BDEs) for the curcumin-related compounds have been calculated using density functional theory (DFT) methods. It was found that the antioxidant mechanism of curcumin was a H-atom abstraction from the phenolic group, not from the central CH2 group in the heptadienone link. Curcumin, methylcurcumin, and half-curcumin had similar O-H BDEs, indicating that the two phenolic groups in curcumin were independent of each other.

A quantum mechanics (QM) method has been used to calculate molecular properties of sodium dodecylbenzenesulfonate (SDBS) in vacuum and in solution. Furthermore, molecular dynamics (MD) simulations have been used to determine the dynamic behavior of SDBS moving from the bulk solution to the air/water interface. QM calculations suggest that two head-group oxygen atoms on each surfactant molecule interact with a Na+ ion, despite the availability of three oxygen atoms in the head group. MD simulations showed that the Na+ ion must overcome the energy barrier between two solvent layers around the head group to form stable ion pair in solution, which is consistent with experimental results. In the simulation, in moving from the bulk to the interface, SDBS can aggregate in a short time, and the adsorption adopts a preferred orientation. The results indicate that formation of favorable hydrophobic interactions of the surfactant alkyl chains is the origin of interfacial adsorption of SDBS.

The thiourea-catalyzed methanolysis of d-lactide, a model system for the initiation and propagation of the organocatalyzed ring-opening polymerization (ROP) of lactide, has been studied by performing density functional theory calculations. Both the catalyzed and uncatalyzed reactions are explored along two possible pathways: one involves the stepwise addition–elimination pathway and the other is related to the concerted pathway. It is found that the reaction without the presence of the catalyst is difficult because the barrier involved is as high as 176 kJ mol–1. With the aid of a thiourea catalyst, the barrier is reduced to 88 kJ mol–1 with a preference for the stepwise addition–elimination mechanism over the concerted one. The role of the catalyst has been rationalized by analyzing the frontier molecular orbital interactions between the catalyst and substrates and by performing natural population analysis. Finally, another mechanism involving acyl transfer is discussed for the thiourea-catalyzed ROP.