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Abstract

The oscillatory behavior of the reaction of partial oxidation of methane has been investigated over metallic nickel surfaces. It was found that the chemical compositions and the reaction temperature within the reactor exhibited regular oscillations over a range of reactor temperatures between 710 and 930 °C with different feed gas compositions at flow rate ratios (Ar/CH4/O2) ranging from 30:29:1 to 30:12:18 cm3 min−1. When the reactor temperature increased, the oscillation frequency increased showing indicative correlations, while the amplitude decreased with the rise in system temperature. Varying feed gas composition resulted in complex changes in oscillatory waveforms, frequencies, amplitudes, and product selectivities. The oscillation was attributed to the cyclic reduction and oxidation of the nickel surface under the reaction conditions.

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Abstract

Purpose

This study aimed to evaluate and identify the value and explore the mechanisms of Angiogenic Factor with G-patch and FHA domains 1 (AGGF1) in postoperative cognitive dysfunction (POCD).

Methods

Rats were separated into four different groups, namely sham, isoflurane, isoflurane + recombinant human Aggf1 (rh-Aggf1) (5 μg kg−1), and isoflurane + rh-Aggf1 (10 μg kg−1). qPCR and western blot assays were applied to detect the correlation between the expression of AGGF1 and isoflurane administration. Then, the Morris water maze (MWM) test was applied to evaluate the effect of AGGF1 on improving the POCD rats. Subsequently, TUNEL assay was applied and the cell apoptosis-related proteins were tested to reveal the anti-apoptotic effect of AGGF1 in POCD rats. Furthermore, the mRNA and protein levels of TNF-α, IL-6, and IL-1β were also detected by qPCR and ELISA to verify the anti-inflammatory effects of AGGF1 on POCD rats. Besides, the protein expression levels of PI3K, Akt, and NF-κB in each group were examined by western blot.

Results

In this study, the results revealed that isoflurane induced a decrease in AGGF1 expression in the hippocampus of aged rats. In addition, exogenous AGGF1 attenuated POCD in aged rats. Meanwhile, exogenous AGGF1 had anti-apoptotic and anti-inflammatory effects in POCD rats. Further research indicated that AGGF1 activated the PI3K/Akt pathway.

Conclusion

AGGF1 has neuroprotective effect against isoflurane-induced cognitive dysfunction in aged rats via activating the PI3K/AKT signaling pathways.

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Acta Biologica Hungarica
Authors:
Huan Zhang
,
Pan Wang
,
Ai-Jun Zhang
,
Xuan Li
,
Ji-Hong Zhang
,
Qi-Lian Qin
, and
Yi-Jun Wu

The housefly is an important resource insect and the housefly larvae are ideal source of food additives. The housefly larvae protein hydrolysates were obtained by enzymatic hydrolysis by alcalase and neutral proteinase. Their antioxidant activities were investigated, including the superoxide and hydroxyl radicalscavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, reducing power and metal chelating activity. The antioxidant activities of both hydrolysates increased with their increasing concentrations. The alcalase hydrolysate (AH) showed higher scavenging activities against hydroxyl radical and superoxide anion radical at low concentrations and higher metal-chelating activity than the neutral proteinase hydrolysate (NPH). The NPH exhibited higher scavenging activity against DPPH free radical and higher reducing power than the AH. Both hydrolysates showed more than 50% superoxide anion radical-scavenging activity at 10 μg/mL. These results indicate that both housefly larvae protein hydrolysates display high antioxidant activities and they could serve as potential natural antioxidant food additives.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Li Yu-guo
,
Huang Xuan
,
Liu Riu-li
,
Li Qing-nuan
,
Zhang Xiao-dong
, and
Li Wen-xin

Summary  

The water-soluble fullerene derivative C60(OH)x was radiolabeled with 67GaCl3. The labeling yields were determined by radio-PLC. The effects of pH, reaction time, temperature and the amount of C60(OH)x on the labeling yields were studied. The stability of 67Ga-C60(OH)x was also examined. The results showed that the labeling yields could reach 97% under the best labeling conditions and the radiochemical purity of 67Ga-C60(OH)x solution kept at 37 °C remained at 88% after 212 hours. The biodistribution studies of 67Ga-C60(OH)x in mice showed a high localization of 67Ga-C60(OH)x in the bone marrow, bone, liver and spleen with slow clearance and a negligible accumulation in the blood. These data suggest that the water-soluble C60(OH)x, having the same properties as microcolloids, may be used as a carrier of drug system for lymphatic targeting.

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Background and aims

Internet gaming disorder (IGD) was proposed in Diagnostic and Statistical Manual of Mental Disorders of American Psychiatric Association as an area warranting more research attention. High prevalence of excessive Internet game use and related addictions has been reported in China, especially among youth; however, there is a lack of psychometrically and theoretically sound instruments for assessing IGD in the Chinese language.

Methods

This study aimed to examine the psychometric properties of a Chinese version of the Internet Gaming Disorder Test (IGD-20 Test) among Chinese middle school (n = 569; M age = 13.34; 46.2% females) and university students (n = 523; M age = 20.12; 48.4% females) samples in Beijing, China. All participants voluntarily completed an anonymous questionnaire.

Results

Confirmatory factor analysis results showed that the Chinese version of the IGD-20 Test had five factors (i.e., salience-tolerance, mood modification, withdrawal, conflict, and relapse). Measurement invariance was confirmed across the two samples. The test score was positively associated with the modified Young’s Internet Addiction Test for gaming addiction. Concurrent validation was further demonstrated by the IGD-20 Test’s positive correlation with weekly gameplay and depression symptoms. The latent profile analysis showed four different gamer classes (i.e., regular gamers, low-risk engaged gamers, high-risk engaged gamers, and probable disordered gamers), with the estimated prevalence of 2.1% of the last group.

Discussion and conclusion

The IGD-20 Test was applicable to Chinese youth and its Chinese version generally demonstrated good psychometric properties.

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Abstract

Background and aims

Internet gaming disorder (IGD) has been recognized as a mental illness. Cognitive and emotional illness representations affect coping and health outcomes. Very little is known about such perceptions related to IGD, in both general and diseased populations. This study examined the psychometric properties of the Revised Illness Perception Questionnaire (IPQ-R) for IGD in a general population that included mostly non-cases while a small proportion of the sample was IGD cases.

Methods

An anonymous cross-sectional telephone survey was conducted in a random sample of 1,501 Chinese community-dwelling adults (41.3% male; mean age = 40.42, SD = 16.85) in Macao, China.

Results

The confirmatory factor analysis identified a modified 6-factor model (i.e., timeline cyclical, consequences, personal control, treatment control, illness coherence, and emotional representations) of 26 items that showed satisfactory model fit and internal consistency. Criterion-related validity was supported by the constructs' significant correlations with stigma (positive correlations: timeline cyclical, consequence, emotional representations; negative correlations: illness coherence). Ever-gamers, compared to never-gamers, reported higher mean scores in the subscales of personal control and illness coherence, and lower mean scores in time cyclical, consequence, and emotional representations. Among the sampled gamers, probable IGD cases were more likely than non-IGD cases to perceive IGD as cyclical and involved more negative emotions.

Conclusions

This study shows that the revised 26-item version of IPQ-R is a valid instrument for assessing illness representation regarding IGD in a general population of Chinese adults. It can be used in future research that examines factors of incidence and prevention related to IGD.

Open access

Abstract

Background and aims

Gambling disorder (GD) is a mental disorder with a relatively higher prevalence in university students compared to adolescents and adults. Its reciprocity with mental being indicators, such as psychological flourishing, would be expected, but prior to this study had not yet been empirically examined. In addition, the predictive value of purpose in life (PIL) on university students' GD and psychological flourishing also remained unknown. This 1-year longitudinal study was the first to test the potential bidirectional relationships among PIL, self-reported GD symptoms, and psychological flourishing.

Methods

In this study, a total of 283 university students (39.6% females; age = 18–27 years, M = 20.47, SD = 1.15) completed an anonymous questionnaire at both baseline and a year later in a follow-up study.

Results

The results of our cross-lagged analysis did not show the hypothesized reciprocity between GD symptoms and psychological flourishing (P > 0.05). However, PIL significantly predicted fewer GD symptoms (β = −0.23, P < 0.001) and higher levels of psychological flourishing (β = 0.30, P < 0.001) in the follow-up study. Moreover, psychological flourishing predicted PIL a year later.

Conclusion

The findings demonstrate the potential efficacy of purpose/meaning oriented interventions in gambling prevention and in well-being promotion programs.

Open access

Abstract  

The mechanism of solvent extraction of uranium(VI) from highly concentrated chloride solution with a quaternary ammonium salt, benzyloctadecyldimethylammonium chloride (BODMAC, R4NCl), dissolved in chloroform was studied. The compositions of the extracted species were R4N.UO2Cl3 and (R4N)2 .UO2Cl4. The extraction process is exothermic (ΔH° = -8.42±0.54 KJ/mol). Kex 1 and Kex 2 are calculated to be (3.62±0.55).10-2 and (1.06±0.17).103, respectively. In the extraction process, a W/O uranium(VI) rich emulsion solution has been formed between the organic and aqueous phases, its volume increased with the increase of BODMAC in the system. The influences of temperature, NaCl, MgCl2 and MgSO4 concentrations on the extraction equilibrium were also studied.

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