27 research outputs found
Psychological Capital, Positive Affect, and Organizational Outcomes: A Three-Wave Cross-Lagged Study
Psychological capital (PsyCap) is a higher-order construct comprising hope, efficacy, optimism, and resiliency, which has attracted more and more attention from both academics and practitioners. Despite promising progress made in the PsyCap literature, the underlying mechanisms linking PsyCap to organizational outcomes still need more investigation utilizing longitudinal research design. Moreover, the reciprocal relationships between PsyCap and positive affect require more attention. Therefore, we aim to test the central role of positive affect in the relationships between PsyCap and affective organizational commitment (AOC) on one hand and organizational citizenship behaviour toward organization (OCBO) on the other hand as well as the reciprocal relationships between PsyCap and positive affect in this study. A three-wave longitudinal survey was conducted using a cross-lagged panel design with a one-month time lag between two consecutive waves. Panel data was collected from 208 workers in Beijing, China. The results support the hypothesis that positive affect serves as a mediator in the relationships between PsyCap and OCBO. Moreover, we also find some support for a reciprocal relationship between PsyCap and positive affect. The theoretical and practical implications of the findings are also discussed
1H-Nuclear magnetic resonance-based metabolomic analysis of brain in mice with nicotine treatment
Reciprocal Relationship Between Psychological Capital and Positive Emotions
This study aims to explore the reciprocal relationship between psychological capital (PsyCap) and positive emotions. A cross-lagged design was adopted for a 3-wave longitudinal study, with a 1-month time lag between each of the 2 time measures. Results indicated a reciprocal relationship between PsyCap and positive emotions
A self-healing and anticorrosion epoxy coating based on the novel polymer filler containing a side-linked grafting 2-mercaptobenzothiazole
The healing mechanism of traditional self-healing coatings can be divided into “extrinsic” and “intrinsic” types according to the reactants, among which intrinsic restorations can be recycled multiple times and have great potential for applications. But epoxy resin is difficult to achieve intrinsic healing process through secondary bonding and reaction between polymers owing to the high chain rigidity and cross-linking density. In this study, a composite coating combining both “extrinsic” and “intrinsic” healing methods has been fabricated by adding a novel polymer filler (MBT-PGMS), which was synthesized via grafting copolymerization of glycidyl-methacrylate, styrene, methyl-methacrylate and 2-mercaptobenzothiazole (MBT). Multiple analytical techniques have been used to characterize the structure and properties of fillers, and the effect on the anti-corrosion performance and self-healing efficiency of epoxy coatings in 3 wt.% NaCl solution has been studied by electrochemistry measurements and mechanical analysis. Results indicated that the intact coating containing MBT-PGMS (MBT-PGMS/EP) showed prominent corrosion resistance during the immersion of 90 days. Once the coating was scratched, the impedance of MBT-PGMS/EP increased gradually with increasing the immersion time, and reached the optimal performance as the filler amount at 5 wt.%, while the impedance modulus was about 2.8 × 108 Ω cm2 after immersion for 144 h. A dynamic crosslinking model in MBT-PGMS/EP has been proposed to explain the self-healing mechanism
Mechanisms of metabonomic for a gateway drug: nicotine priming enhances behavioral response to cocaine with modification in energy metabolism and neurotransmitter level.
Nicotine, one of the most commonly used drugs, has become a major concern because tobacco serves as a gateway drug and is linked to illicit drug abuse, such as cocaine and marijuana. However, previous studies mainly focused on certain genes or neurotransmitters which have already been known to participate in drug addiction, lacking endogenous metabolic profiling in a global view. To further explore the mechanism by which nicotine modifies the response to cocaine, we developed two conditioned place preference (CPP) models in mice. In threshold dose model, mice were pretreated with nicotine, followed by cocaine treatment at the dose of 2 mg/kg, a threshold dose of cocaine to induce CPP in mice. In high-dose model, mice were only treated with 20 mg/kg cocaine, which induced a significant CPP. (1)H nuclear magnetic resonance based on metabonomics was used to investigate metabolic profiles of the nucleus accumbens (NAc) and striatum. We found that nicotine pretreatment dramatically increased CPP induced by 2 mg/kg cocaine, which was similar to 20 mg/kg cocaine-induced CPP. Interestingly, metabolic profiles showed considerable overlap between these two models. These overlapped metabolites mainly included neurotransmitters as well as the molecules participating in energy homeostasis and cellular metabolism. Our results show that the reinforcing effect of nicotine on behavioral response to cocaine may attribute to the modification of some specific metabolites in NAc and striatum, thus creating a favorable metabolic environment for enhancing conditioned rewarding effect of cocaine. Our findings provide an insight into the effect of cigarette smoking on cocaine dependence and the underlying mechanism
Griseofulvin Derivative and Indole Alkaloids from <i>Penicillium griseofulvum</i> CPCC 400528
A new griseofulvin derivative, 4′-demethoxy-4′-<i>N</i>-isopentylisogriseofulvin (<b>1</b>), three new indole
alkaloids, 2-demethylcyclopiamide E (<b>2</b>), 2-demethylsperadine
F (<b>3</b>), and clopiamine C (<b>4</b>), and five known
metabolites (<b>5</b>–<b>9</b>) were isolated from <i>Penicillium griseofulvum</i> CPCC 400528. Compound <b>1</b> is the first reported griseofulvin analogue with an <i>N</i>-isopentane group and the first example of a naturally occurring
N-containing griseofulvin analogue. Their structures and absolute
configurations were elucidated through extensive spectroscopic analyses,
calculated ECD, and single-crystal X-ray diffraction (Cu Kα).
The possible biogenetic pathway of <b>1</b>–<b>3</b> was proposed. Compounds <b>1</b>, <b>2</b>, and <b>5</b> exhibited anti-HIV activities with IC<sub>50</sub> values
of 33.2, 20.5, and 12.6 μM, respectively
Validation plots of the PLS models after application of OSC in striatum.
<p>(A) control vs. 20 mg/kg cocaine; (B) control vs. nicotine +2 mg/kg cocaine; (C) 2 mg/kg cocaine vs. nicotine +2 mg/kg cocaine; (D) control vs. nicotine; (E) control vs. 2 mg/kg cocaine.</p
Validation plots of the PLS models after application of OSC in NAc.
<p>(A) control vs. 20 mg/kg cocaine; (B) control vs. nicotine +2 mg/kg cocaine; (C) 2 mg/kg cocaine vs. nicotine +2 mg/kg cocaine; (D) control vs. 2 mg/kg cocaine.</p
600 MHz CPMG <sup>1</sup>HNMR spectra of the NAc from mice.
<p>(A) control; (B) 2 mg/kg cocaine; (C) 20 mg/kg cocaine; (D) nicotine; (E) nicotine +2 mg/kg cocaine.</p