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  • Author or Editor: Ying Yang x
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Abstract

Visualization of subject structure based on co-word analysis is used to explore the concept network and developmental tendency in certain field. There are many visualization methods for co-word analysis. However, integration of results by different methods is rarely reported. This article addresses the knowledge gap in this field of study. We compare three visualization methods: Cluster tree, strategy diagram and social network maps, and integrate different results together to one result through co-word analysis of medical informatics. The three visualization methods have their own character: cluster trees show the subject structure, strategic diagrams reveal the importance of topic themes in the structure, and social network maps interpret the internal relationship among themes. Integration of different visualization results to one more readable map complements each other. And it is helpful for researchers to get the concept network and developmental tendency in a certain field.

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Authors: Ying Liu, Guoxuan Liu, Yali Yang, Sufang Niu, Fuguang Yang, Shaoxia Yang, Jianian Tang and Jianping Chen

An efficient and reproducible protocol is described for shoot-bud regeneration and Agrobacterium tumefaciens-mediated genetic transformation of J. curcas. Treating the explants with high concentrations (5–120 mg/L) of TDZ for short durations (5–80 min) before inoculation culture increased significantly the regeneration frequency and improved the quality of the regenerated buds. The highest shoot-buds induction rate (87.35%) was achieved when petiole explants were treated with 20 mg/L TDZ solution for 20 min and inoculated on hormone-free MS medium for 30 days. Regenerated shoots of 0.5 cm or a little longer were isolated and grafted to seedling stocks of the same species, and then the grafted plantlets were planted on half-strength MS medium containing 0.1 mg/L IBA and 2 mg/L sodium nitroprusside (SNP). This grafting strategy was found to be very effective, to obtain that healthy grafted plantlets ready for acclimatization within 20 days. By the above mentioned protocol and with general Agrobacterium – mediated genetic transformation methods only 65 days were needed to obtain intact transgenic plants.

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Abstract

Using a collection of papers gathered from the Web of Science, and defining disciplines by the JCR classification, this paper compares the disciplinary structure of the G7 countries (representing high S&T level countries) and the BRIC countries (representing fast breaking countries in S&T) by using bibliometric methods. It discusses the similarity and the balance of their disciplinary structure. We found that: (1) High S&T level countries have a similar national disciplinary structure; (2) In recent years the disciplinary structure of the BRIC countries has become more and more similar to that of the G7 countries; (3) The disciplinary structure of the G7 countries is more balanced than that of the BRIC countries (4) In the G7 countries more emphasis goes to the life sciences, while BRIC countries focus on physics, chemistry, mathematics and engineering.

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This study aims at establishing a thin-layer chromatographic (TLC) scanning method for the determination of three alkaloids in Sophora alopecuroides and preliminary screening of antioxidant active components in S. alopecuroides with TLC—bioautography technology. The alkaloids in S. alopecuroides were identified by silica gel thin-layer chromatography; the expansion agent was toluene— acetone—methanol—ammonia—water (8:3:0.2:0.5:8), and the chromogenic agent was modified bismuth potassium iodide solution, sophoridine, matrine, and sophocarpine in S. alopecuroides by TLC scanning at 500 nm. The linear ranges were 0.4152–2.4912 μg for sophordine, 0.4245–2.5470 μg for matrine, and 0.4101– 2.4606 μg for sophocarpine, with correlation coefficients of 0.9939, 0.9956, and 0.9975. Ultraviolet (UV) method was used to determine the total scavenging activity of the 2,2-diphenyl-1-picrylhdrazyl (DPPH) free radical. The best TLC identification condition was selected, and the antioxidant activity of DPPH was screened with the color. DPPH tests indicated that IC50 of S. alopecuroides was 0.40 mg mL−1. The TLC—bioautography technology showed the alkaloids in the purple background, and a white spot was not evident. Precision, accuracy, and repeatability of the TLC scanning method were evaluated, and the results were in accordance with the requirements of methodology validation. S. alopecuroides exhibits certain antioxidant activity, but the three alkaloids do not exhibit an evident antioxidant effect, and the unknown components of S. alopecuroides show weak antioxidant effect. The specific components need further studies.

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Authors: Yun Zhou, Guifeng Huang, Xiaolan Li, Feng Chen, Hong Liu, Ying Yang, Zhong Fan, Jinghui Jiang and Jun Yang

A credible method for determination of the aglycon moieties of glycosidically bound aroma compounds in Flos Chrysanthemi by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS) has been proposed. The aglycon moieties of glycosidically bound aroma compounds were isolated using methyl-tert-butyl ether (MTBE) extraction following enzymatic hydrolysis. The GC × GC–TOFMS analysis was performed to comprehensively identify different forms of the released aroma components in Flos Chrysanthemi. The result shows that the limit of detection of the released aglycon moieties ranged from 0.3 to 3.1 ng/mL, the recovery of the released 1-octanol was better than 98.3%, and the intra-day and inter-day precisions of this method were 0.2 to 8.9% and 1.3 to 9.1%, respectively. The proposed method was applied to the analysis of four types of Flos Chrysanthemi (Chuju, Boju, Hangju, and Gongju). A total of 60 aglycon moieties of interest were identified in the four types of Flos Chrysanthemi. These aglycones mainly consisted of aliphatic, aromatic, monoterpene, C13-norisoprenoids, and miscellaneous compounds.

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The 21st century is a knowledge economic era when a person who could master knowledge and technologies could master the competitive future. The knowledge and technology competition and the emergence of information technology and the Internet in the future have innovation strategies enter a new era. Knowledge management and share as well as innovation strategies of a business present the importance on the enhancement of competitive advantages. Effective knowledge management and innovation strategies become the key in the success.

Aiming at Kunshan German Industrial Park, the executives and employees in 6 of top 500 businesses are distributed 300 copies of questionnaires, among which 218 valid copies are retrieved, with the retrieval rate 73%. The research results show the significant correlations between 1. innovation strategies and competitive advantages, 2. knowledge management and innovative strategies, and 3. knowledge management and competitive advantages. It is expected to assist businesses in constructing knowledge management.

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Background and aims

Internet pornography consumption is prevalent among college students and problematic for some, yet little is known regarding the psychological constructs underlying problematic Internet pornography use (PIPU). Drawing on the Interaction of Person-Affect-Cognition-Execution model, this study tested a model that sexual sensation seeking (SSS) would impact PIPU through online sexual activities (OSAs) and that this relationship would be influenced by the third-person effect (TPE; a social cognitive bias relating to perceived impacts on others as compared to oneself) in a gender-sensitive manner.

Methods

A total of 808 Chinese college students (age range: 17–22 years, 57.7% male) were recruited and surveyed.

Results

Men scored higher than women on OSAs and PIPU and on each scale’s component factors. The relationship between SSS and PIPU was mediated by OSAs, and the TPE moderated this relationship: the predictive path (SSS to PIPU) was significant only in participants with high TPE. The moderated mediation model was not invariant across gender groups, with data suggesting that it accounted for a greater proportion of the variance in men as compared with women.

Discussion and conclusions

The findings suggest that SSS may operate through participation in OSAs to lead to PIPU, and this relationship is particularly relevant for college-aged males scoring high on the TPE. These findings have implications for individuals who might be particularly vulnerable to developing PIPU and for guiding educational efforts and targeting interventions in college-aged students. The extent to which these findings extend to other age groups and cultures warrants further examination.

Open access

Abstract  

Salicylaldimine functionalized SBA-15 hybrid mesoporous material was synthesized by post-grafting of salicylaldehyde modified 3-aminopropyltriethoxysilane and followed by introducing Cu(II) ions into the hybrid material via a ligand exchange reaction. The prepared catalyst was characterized by means of XRD, N2 adsorption/desorption, SEM, FT-IR, UV–vis spectroscopy, EPR and XPS techniques as well as ICP-AES and elemental analysis measurements. The solid catalyst was evaluated in the oxidation of styrene with H2O2 as the oxidant under mild conditions, and the reaction parameters (the molar ratio of styrene/H2O2, amount of catalyst, temperatures, solvents, alkaline additive) were investigated and optimized for the oxidation of styrene. The optimal conversion (77.1%) and yield of styrene oxide (60.0%) were obtained at 80 °C using CH3CN as the solvent under basic conditions. Moreover, the covalently anchored Cu(II) salicylaldimine complex showed good recoverability and high stability against leaching of active copper(II) species.

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Authors: Xiao-Tao Wang, Ying-Kui Yang, Zhi-Fang Yang, Xing-Ping Zhou, Yong-Gui Liao, Chen-Chen Lv, Feng-Chih Chang and Xiao-Lin Xie

Abstract  

Vinylated polyhedral oligomeric silsesquioxane (POSS-M) was prepared by the reaction of POSS containing amine groups with acrylic acid. Azobenzene liquid crystalline copolymer (LCP-POSS) was then synthesized with 6.0 mol% POSS-M and 94.0 mol% acrylate monomer containing azobenzene liquid crystalline moiety (Azo-M) by free-radical copolymerization. Homopolymer of Azo-M (LCP) was also synthesized under the same conditions. Their thermal properties and liquid crystallinity were characterized by Thermal gravimetric analysis (TG), differential scanning calorimetry (DSC), Wide-angle X-ray diffraction experiments (XRD) and polarized optical micrographs (POM). The results showed that LCP-POSS has higher thermal stability and glass transition temperature than pure LCP due to the incorporation of the rigid cage-like POSS. Especially, LCP-POSS exhibits enantiotropic smectic and nematic liquid crystalline behaviors, its smectic-nematic transition temperature (T SN) and nematic-isotropic transition temperature (T NI) are higher than those of pure LCP, which may promote and extend its applications on stimuli-responsive materials and devices.

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Authors: Yang Ya-xin, Wu Xin-min, Lin Jun, Liu Qing-chen, Den Ju-zhi, Huang Hong-bo, Jiang Zhong-ying and Hsia Yuan-fu

Abstract  

Soil thermolumicenscence (TL), one of the methods for uranium exploration, is based on the glowing characteristics of the crystal minerals such as quartz in the nature. The paper deals with the experiments at Xiazhuang uranium ore-field, in order to show the availability of the thermoluminescence to explore granite-hosted uranium mineralization. Meanwhile, some constraints for application are discussed.

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