Social networking sites (SNSs) have become increasingly common in recent years, and their use has become integrated into the daily lives of millions of people across the world. Attracting new users ...and retaining existing ones are critical to the success of SNS providers. This study applies the push‐pull‐mooring model of the migration theory to improve our understanding of factors that influence the switching behavior of SNS users. Following the migration theory, this study empirically examines the three categories of antecedents for SNS switching intention: push (i.e., dissatisfaction and regret), pull (i.e., alternative attractiveness), and mooring (i.e., switching costs) factors. The results show that the three categories of factors had varying degrees of effects on switching intention. Additionally, the strong moderation effects of both pull and mooring factors help answer the question why switching does not necessarily occur when push factors are in effect. Managerial implications are provided.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A method for Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters was developed. The reaction has a broad substrate scope. This hydroalkylation shows excellent regio- and ...stereo-selectivity. This method enables readily available starting materials to be used to access a range of cyano-substituted single-configuration trisubstituted alkenes. These are valuable feedstock chemicals and are widely used in synthetic and medicinal chemistry.
A method for Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters was developed.
Purpose
– The focus in this study is a model that predicts continuance intention of online multi-player games. In this integrated model, the social cognitive theory (SCT) lays out the foundation of ...two types of pre-use (pre-play) expectations, the flow theory captures the affective feeling with the game as a moderator for the effect from the two pre-use expectations, and subjective norm together with its associated antecedents cover a wide spectrum of social influences.
Design/methodology/approach
– A questionnaire was designed and pre-tested before distributing to target respondents. The reliability and validity of the instrument both met the commonly accepted guidelines. The integrated model was assessed first by examining its measurement model and then the structural model.
Findings
– The integration of cognitive, affective and social influence in this model explains a larger amount of variance compared to the competing models and existing studies.
Originality/value
– Unlike a popular trend that studies predictors of online games from either cognitive or affect angle, the work looks at both together to study how their joint effect is related to continuance intention. This marks an important improvement as cognitive expectations derived from SCT captures the pre-use experience that may be influenced or swayed by sources including those that are inflated or incorrect. By studying flow as a moderator in conjunction with other sources of influence, the authors are able to further the understanding of how the pre-use expectations may be shaped by one's own experience.
A Ni-catalyzed Suzuki-type cross-coupling of boronic acids with epoxides without an exogenous base and with broad substrate scope has been developed. The product selectivity of styrenyl epoxides is ...different from that of previous work. This methodology uses readily available starting materials to access a range of substituted alcohols, which are valuable feedstock chemicals.
A Ni-catalyzed Suzuki-type cross-coupling of boronic acids with epoxides without an exogenous base and with broad substrate scope has been developed.
The factors that influence the adoption of online gaming are a major topic of concern for academic researchers, online games marketers, and developers alike. By integrating a motivational perspective ...into the social cognitive theory (SCT), the research model in this study captures both internal (self-efficacy) and external (social influence) factors when explaining and predicting gamers' outcome expectations, trust, and intention to play online games. Moreover, this study investigates the moderating role of gender in attaining a better understanding of the relationship between behavioral intention and its antecedents. This study finds that self-efficacy, social influence, trust, and utilitarian and hedonic outcome expectations significantly influence players' intentions to play online games. This study also presents that gender moderates the relationship between personal cognitive factors (i.e. self-efficacy, utilitarian and hedonic outcome expectations, and trust) and behavioral intentions, and between environmental influence (i.e. social influence) and behavioral intentions. The findings herein are able to help online game marketers and developers to better develop online games in order to enhance gamers' intentions to play.
•This study developed a theoretical model based on social cognitive theory.•Exploring the gender differences in the context of online games•The proposed research model is evaluated using structural equation modeling.•The results help marketers design online games to enhance users' intention to play.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The great success achieved by the two highly-effective messenger RNA (mRNA) vaccines during the COVID-19 pandemic highlights the great potential of mRNA technology. Through the evolution of mRNA ...technology, chemistry has played an important role from mRNA modification to the synthesis of mRNA delivery platforms, which allows various applications of mRNA to be achieved both
in vitro
and
in vivo
. In this tutorial review, we provide a summary and discussion on the significant progress of emerging mRNA technologies, as well as the underlying chemical designs and principles. Various nanoparticle (NP)-based delivery strategies including protein-mRNA complex, lipid-based carriers, polymer-based carriers, and hybrid carriers for the efficient delivery of mRNA molecules are presented. Furthermore, typical mRNA delivery platforms for various biomedical applications (
e.g.
, functional protein expression, vaccines, cancer immunotherapy, and genome editing) are highlighted. Finally, our insights into the challenges and future development towards clinical translation of these mRNA technologies are provided.
This review highlights significant progress in mRNA delivery platforms and therapeutic applications from the view of chemistry. Insights into the challenges and future development towards clinical translation of mRNA therapeutics are also provided.
•1 Five kinds of hydrophobic DESs were designed and prepared for the first time.•2 The prepared DESs showed high extraction efficiency for formaldehyde (HCHO).•3 The DES was applied to extract and ...determine of HCHO in biological and gas samples.•4 Hydrophobic DESs based VA-LLME combined with HPLC method was developed.
Hydrophobic deep eutectic solvents (DESs) are a new class of green solvents, and their research and application are a brand new area. So far, only a few hydrophobic DESs have been reported as extraction solvents. In this paper, five kinds of hydrophobic DESs composed of trioctylmethylammonium chloride and hydroquinone, 4-phenylphenol or 4-cyanophenol are designed and prepared for the first time. Melting point / glass transition temperature and density are also determined for these DESs. Coupled with HPLC, these hydrophobic DESs have been used as extractants in vortex-assisted liquid-liquid microextraction for the selective enrichment and indirect determination of formaldehyde. The optimization of reaction and extraction conditions, such as pH value, reaction time and temperature, concentration of 2,4-dinitrophenylhydrazine, type and dosage of the extraction solvent, speed and time of vortex, salt addition and centrifugation time are investigated in detail. It is found that under the optimized experimental conditions, the calibration curve of this method is linear in the range of 1.0–200.0 μg L−1 with the linear correlation coefficient (r2) of 0.9994. The limit of detection (S/N = 3) and limit of quantification (S/N = 10) are 0.2 μg L−1 and 1.0 μg L−1, and the intra-day and inter-day precision (RSD, n = 5) are 1.1% and 3.5%, respectively. The interference of some common coexisting ions and neutral molecules have been also tested. The proposed method has been successfully used for the determination of formaldehyde from biological and indoor air samples. The recovery of formaldehyde is in the range from 83.1% to 104.4%, and the relative standard deviation is lower than 5.9%. Furthermore, the analytical parameters of the proposed method have been compared with other extraction and microextraction methods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Agarwood is a resinous heartwood of Aquilaria sinensis that is formed in response to mechanical wounding. In the present study pre-treatment of Aquilaria sinensis was carried out, and then the ...dominant fungi were isolated and purified from the surface and electroshock holes of trees. The isolated Trichoderma sp. and Neurospora sp. were then screened for resistance against benzyl acetone and then inoculated into healthy Aquilaria sinensis trees. After six months, the agarwood was collected for analysis. The chemical composition of incense was analyzed using gas chromatography-mass spectroscopy, and 82 chemical constituents were identified. Agarwood products formed by using Trichoderma sp. and Neurospora sp. consisted of 50.22% and 48.71% ether extracts, respectively, which surpassed the 10% threshold specified by the Chinese Pharmacopoeia. Similarly, relative aromatic contents in the two agarwood products were 30.1% and 32.86%, while proportions of sesquiterpene constituents were 10.21% and 11.19%, respectively. These two agarwood-specific chemical constituents accounted for a large proportion of the total chemical composition, which showed that the generated agarwood was of good quality. The results of the study revealed that both Trichoderma sp. and Neurospora sp. were able to effectively induce agarwood production in Aquilaria sinensis trees in 6 months. This study expands the library of fungi that promote the production of agarwood from Aquilaria sinensis trees.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we propose a polynomial fuzzy observer controller for nonlinear systems, where the design is achieved through the stability analysis of polynomial-fuzzy-model-based (PFMB) ...observer-control system. The polynomial fuzzy observer estimates the system states using estimated premise variables. The estimated states are then employed by the polynomial fuzzy controller for the feedback control of nonlinear systems represented by the polynomial fuzzy model. The system stability of the PFMB observer-control system is analyzed based on the Lyapunov stability theory. Although using estimated premise variables in polynomial fuzzy observer can handle a wider class of nonlinear systems, it leads to a significant drawback that the stability conditions obtained are nonconvex. Matrix decoupling technique is employed to achieve convex stability conditions in the form of sum of squares. We further extend the design and analysis to polynomial fuzzy observer controller using a sampled-data technique for nonlinear systems, where only sampled-output measurements are available. Simulation examples are presented to demonstrate the feasibility and validity of the design and analysis results.
Biological entities are involved in intricate and complex interactions, in which uncovering the biological information from the network concepts are of great significance. Benefiting from the ...advances of network science and high-throughput biomedical technologies, studying the biological systems from network biology has attracted much attention in recent years, and networks have long been central to our understanding of biological systems, in the form of linkage maps among genotypes, phenotypes, and the corresponding environmental factors. In this review, we summarize the recent developments of computational network biology, first introducing various types of biological networks and network structural properties. We then review the network-based approaches, ranging from some network metrics to the complicated machine-learning methods, and emphasize how to use these algorithms to gain new biological insights. Furthermore, we highlight the application in neuroscience, human disease, and drug developments from the perspectives of network science, and we discuss some major challenges and future directions. We hope that this review will draw increasing interdisciplinary attention from physicists, computer scientists, and biologists.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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