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This study modelled the rational factors that predict fake news sharing behaviour. It also tested the moderating role of social media literacy skills. The focus was on social media users in Nigeria. An online survey was conducted to gather the responses from participants across Nigerian geopolitical zones. Structural equation modelling (SEM) Smart PLS 3.6 was used to analyse the data. We found that information sharing, the news finds me perception, trust in social media and status-seeking lead to fake news sharing among social media users in Nigeria. Specifically, trust in social media and status-seeking had a greater effect on fake news sharing behaviour. We also found that social media literacy skills significantly moderate the relationship between information sharing, status-seeking, the news finds me perception, trust in social media and fake news sharing in such a way that the effects/relationships are stronger among those with low social media literacy skills. This outcome contributes to theory and practice which was highlighted in the concluding aspect of this study.  相似文献   
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The increasing number of nanoparticles (NPs) being used in various industries has led to growing concerns of potential hazards that NP exposure can incur on human health. However, its global effects on humans and the underlying mechanisms are not systemically studied. Human embryonic stem cells (hESCs), with the ability to differentiate to any cell types, provide a unique system to assess cellular, developmental, and functional toxicity in vitro within a single system highly relevant to human physiology. Here, the quantitative proteomics approach is adopted to evaluate the molecular consequences of titanium dioxide NPs (TiO2 NPs) exposure in hESCs. The study identifies ≈328 unique proteins significantly affected by TiO2 NPs exposure. Proteomics analysis highlights that TiO2 NPs can induce DNA damage, elevated oxidative stress, apoptotic responses, and cellular differentiation. Furthermore, in vivo analysis demonstrates remarkable reduction in the ability of hESCs in teratoma formation after TiO2 NPs exposure, suggesting impaired pluripotency. Subsequently, it is found that TiO2 NPs can disrupt hESC mesoderm differentiation into cardiomyocytes. The study unveils comprehensive changes in the molecular landscape of hESCs by TiO2 NPs and identifies the impact which TiO2 NPs can have on the pluripotency and differentiation properties of human stem cells.  相似文献   
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Travel planning and recommendation have received significant attention in recent years. In this light, we study a novel problem of discovering probabilistic nearest neighbors and planning the corresponding travel routes in traffic-aware spatial networks (TANN queries) to avoid potential time delay/traffic congestions. We propose and study four novel probabilistic TANN queries. Thereinto two queries target at minimizing the travel time, including a congestion-probability threshold query, and a time-delay threshold query, while another two travel-time threshold queries target at minimizing the potential time delay/traffic congestion. We believe that TANN queries are useful in many real applications, such as discovering nearby points of interest and planning convenient travel routes for users, and location based services in general. The TANN queries are challenged by two difficulties: (1) how to define probabilistic metrics for nearest neighbor queries in traffic-aware spatial networks, and (2) how to process these TANN queries efficiently under different query settings. To overcome these challenges, we define a series of new probabilistic metrics and develop four efficient algorithms to compute the TANN queries. The performances of TANN queries are verified by extensive experiments on real and synthetic spatial data.  相似文献   
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Matthew O.T. Cole 《Automatica》2012,48(9):2377-2380
This paper describes the construction of low-pass FIR filters for application as command input shapers in motion control systems. The filters are designed to operate on an arbitrary command input signal to ensure a finite settling time for system modes with known natural frequency and damping ratio. In addition, the required roll-off rate of the filter frequency response may be prescribed in the design. Excitation of unmodeled high-frequency modes can thereby be reduced. The filters also produce an input-smoothing effect that is useful in situations where discontinuities in the input signal or its derivatives would be detrimental to system performance or function. Numerical case studies are presented to clarify these effects.  相似文献   
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Cell adhesion can be a potential problem as well as a valuable tool for microbiological engineering. It can lead to biofouling, contamination of product and corrosion. On the other hand, cell adhesion is purposely employed in fermenters and bioreactors to influence reactor performance. This paper presents an overview of organo-functional silanes – their chemistry, properties, use, and the main laboratory experiments that can be of interest to the food and beverage industry. The purpose is to introduce and explore possibilities for using organo-silane combinations to enhance or reduce microbial adhesion.  相似文献   
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以4-羟基苯甲酸乙酯为原料,经烃化、水解、缩合反应,合成了6个酰胺类衍生物。其结构经核磁共振氢谱、碳谱和高分辨质谱进行了表征,并对人体肿瘤细胞株进行了初步体外抗肿瘤活性评价。结果表明化合物N-(4-氟苯基)-4-苯氧基苯甲酰胺具有良好的抗肿瘤活性。  相似文献   
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