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A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite was successfully designed to overcome this bottleneck. We report a new zero-dimensional (0D) hybrid perovskite of [MP]

For the rational design of metal catalyst in olefin polymerization catalysis, various strategies were applied to suppress the chain transfer by bulking up the axial positions of the metal center, among which the “sandwich” type turned out to be an efficient category in achieving high molecular weight polyolefin. In the α-diimine system, the “sandwich” type catalysts were built using the typical 8-aryl-naphthyl framework. In this contribution, by introducing the rotationally restrained benzosuberyl substituent into the ortho-position of N-aryl rings, a new class of “sandwich-like” α-diimine nickel catalysts was constructed and fully identified. The rotationally restrained benzosuberyl substituents played a “sandwich-like” function by capping the nickel center from two axial sites. Compared to the nickel catalyst Ni1 bearing freely rotated benzhydryl substituent, Ni2 featuring benzosuberyl substituent enabled the increase (8 times) of polymer molecular weights from 8 kDa to 65 kDa in the polymerization of ethylene. By further increasing the steric bulk of another ortho-site of the N-aryl ring, the polymer molecular weight even reached an ultrahigh level of 833 kDa (Mw=1857 kDa) using the optimized Ni3. Notably, these nickel catalysts could also mediate the copolymerization of ethylene with methyl 10-undecenoate, with Ni3 giving the highest copolymer molecular weight (88 kDa) and the highest incorporation of comonmer (2.0 mol%), along with high activity of up to 105 g·mol−1·h−1.

Alzheimer's disease (AD) is a severe neurodegenerative disorder of the central nervous system (CNS) characterized by neuron loss and dementia. Previous abundant evidence demonstrates that the first critical step in the course of AD is the state of oxidative stress and the neuronal loss is closely related to the interaction of several signalling pathways. The neuroprotective efficacy of Rho-associated protein kinase (ROCK) inhibitor in the treatment of AD has been reported, but its exact mechanism has not been well elucidated. The purpose of this study is to investigate the therapeutic effects of Fasudil on amyloid precursor protein/presenilin-1 (APP/PS1) mice and to discover the potential underlying mechanism. Sixteen 8-month-old APP/PS1 mice were divided into model and Fasudil treatment groups and 8 wild-type mice were used as a normal control group. After the behavioural test, all mice were sacrificed for immunofluorescence and other biochemical tests. The results showed that the administration of Fasudil improved learning and memory ability, elevated the concentration of antioxidative substances and decreased lipid peroxides, as well as inhibited neuronal apoptosis by increasing the expression of B-cell lymphoma-2 (Bcl-2) (p < 0.05), reducing Bcl-2 Associated X (Bax) (p < 0.05) and cleaved caspase-3 (p < 0.05) of APP/PS1 mice. Moreover, Fasudil treatment also ameliorated the phosphorylation of p38 (p < 0.01), c-Jun N-terminal kinase (JNK) (p < 0.001) and extracellular regulated protein kinases (ERK) (p < 0.001), and accelerated the nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) (p < 0.01) expression and its antioxidative downstream molecules (p < 0.05, p < 0.05, and p < 0.05, respectively). Data from the present study demonstrate that Fasudil significantly restored cognitive function, restrained oxidative stress and reduced neuronal apoptosis in the hippocampus, probably by inhibiting ROCK/MAPK and activating Nrf2 signalling pathways in APP/PS1 mice.

Crowdsourcing is an emerging web-enabled method to gain external expertise and ideas on tasks or projects. Mass contributions from the crowd are the key to the success and effectiveness of crowdsou...

With the emergence of Internet technology, Internet ethics has become an important issue for academics and practitioners. This study aims to investigate the factors that influence students’ behavio...

While increasing productivity and economic growth, the application of artificial intelligence (AI) may ultimately require millions of people around the world to change careers or improve their skil...

Business simulation games (BSGs) are educational tools that help students develop business management knowledge and skills. However, to date, relatively little research has investigated the factors that influence students’ BSG usage intention. Grounded on the extended unified theory of acceptance and use of technology, this study helped to fill this gap by exploring intention to use BSGs. Specifically, this study investigated the influence of performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, and price value on behavioral intention to use BSGs. Data collected from 141 useful respondents were tested against the research model using partial least square approach. The results of this study indicated that behavioral intention to use BSGs was influenced by facilitating conditions, hedonic motivation, and price value. Unexpectedly, performance expectancy, effort expectancy, and social influence were not predictive of students’ behavioral intention to use BSGs. These findings enhanced our understanding of students’ BSG usage behavior and provided several important theoretical and practical implications for the application of BSG in the context of business and management education.

Owing to the excellent seismic resistance of circular concrete-filled steel tubes (CFST), no specific limitation on their in-service axial load level is provided in Chinese codes. Therefore, nonlinear creep could occur in Chinese CFST applications. This study intends to experimentally investigate the nonlinear creep behaviour and the creep failure behaviour of CFST columns. Fourteen specimens were subjected to sustained loading for 200–500 days. The sustained loading level ranged between 40% and 80% of the cross-sectional strength of the specimens. The strain state of steel tubes was monitored to determine how the confinement effects vary with time. Ultimate loading tests were finally conducted on all specimens immediately after the long-term tests to investigate the nonlinear creep effects on the cross-sectional capacity and ductility of the CFST specimens. A method was then proposed for the nonlinear creep analysis of circular CFST members with consideration of the beneficial contribution of confinement effects. Existing nonlinear models were benchmarked against available experimental results to evaluate their adequacy in predicting the nonlinear creep responses of CFST members. Experimental results indicated that nonlinear creep could lead to a 58–200% increase in the creep coefficient, in which case the linear creep model will underestimate the long-term deformation by 37–67%. Owing to the vertical stress redistribution between the concrete core and the steel tube and the confinement effects, no creep failure occurred during the 500-day tests, and the nonlinear creep barely influenced the cross-sectional capacity of the specimens. A model was recommended to predict the nonlinear creep deformation of CFST members.

This chapter presents a state-of-the-art review of the time-dependent behaviour of composite columns. The first part of the chapter outlines the available typologies and advantages of composite columns. This is followed by an overview of the time-dependent response of concrete (specific to composite columns) and an introduction to concrete confinement. The main part of the chapter is devoted to the state-of-the-art review on how concrete time effects influence the long-term and ultimate behaviour of concrete-filled steel tube (CFST) columns, and on the combined effects produced by sustained loading and chloride corrosion on CFST columns. The review then deals with the long-term behaviour of concrete-filled double skin tube (CFDST) and encased composite columns. The final parts of the chapter provide a review of the time-dependent differential axial shortening (DAS) in vertical components of multi-storey buildings and on the long-term response of arch bridges.

The psychological effects of information technology (IT) use have been widely reported and assessed in the literature. However, although concerns are growing regarding the potential physiological i...

With the proliferation of paid mobile learning applications (m-learning apps), understanding how to assess their success has become an important issue for academics and practitioners. Based on the ...

Purpose Grounded on the value-based adoption model and innovation diffusion theory, this study examined consumer purchase decisions of mobile Global Positioning System (GPS) navigation apps. In addition, this study also investigated the moderating role that perceived availability of free substitutes (PAFS) plays in the relationship between perceived value and purchase intention. The paper aims to discuss these issues. Design/methodology/approach Data collected from 219 mobile users were analyzed against the research model using the partial least squares approach. Findings The results showed that compatibility, relative advantage, perceived enjoyment, perceived cost (positively), and complexity (negatively) influenced these users’ value perceptions and purchase decisions. Furthermore, PAFS significantly weakened the positive relationship between perceived value and purchase intentions. Practical implications Based on these findings, the authors provide practical suggestions for mobile app developers to increase mobile app sales. This study also helps advance knowledge of mobile internet marketing. Originality/value This study is a pioneering effort in explaining consumer purchase intentions in the context of mobile GPS navigation app.

We develop and validate a technology upgrade model (TUM) to explain users system upgrade behavior.Procedural switching costs and benefits loss costs affect upgrade intention through both inertia and perceived need.Incumbent system habit affects upgrade intention through inertia.Social norms affect upgrade intention through perceived need.Inertia weakens the positive relationship between perceived need and upgrade intention. While prior research has recognized users upgrading behavior as a key to successful tech-innovation adoption, few studies have investigated the determinants of the behavioral intention to upgrade. The current paper bridges this gap through an exploration of upgrade intentions that incorporates the status quo bias (SQB) theory with Warshaws purchase intention model (PIM). Data collected from 213 system users was analyzed using partial least squares (PLS). The results show that perceived need (positively) and inertia (negatively) influenced users behavioral intentions to upgrade to a new generation system. The indirect effects of inertia mediated the impact of incumbent system habit, procedural switching costs, and benefit loss costs on the behavioral intention to upgrade. In addition, perceived need mediated the impacts of procedural switching costs, benefit loss costs, and social norms on the behavioral intention to upgrade. Finally, inertia significantly weakened the positive relationship between perceived need and behavioral intention to upgrade. Based on these findings, this study proposed a theoretical framework of a technology upgrade model (TUM) and provided valuable information to both academics and practitioners that is highly pertinent to understanding IT upgrading behaviors.

Purpose– Though prior research has recognized business skills as one of the keys to successful information system development, few studies have investigated the determinants of an IS developer’s behavioral intention to learn such skills. Based on the motivation-ability-role perception-situational factors (i.e. the MARS model), the purpose of this paper is to argue that the intention of IS developers to acquire business skills is influenced by learning motivation (M), learning self-efficacy (A), change agent role perception (R), and situational support (S).Design/methodology/approach– Data collected from 254 IS developers are analyzed using the partial least squares technique.Findings– Results show that a developer’s intention to learn business skills is positively influenced by intrinsic learning motivation and both absolute and relative learning self-efficacy. Furthermore, in comparison to two other change agent roles, the advocate role leads to a significantly higher level of learning intention. Finally, work and non-work support positively influence both extrinsic and intrinsic learning motivation. Notably, non-work support has a greater impact on both absolute and relative learning self-efficacy.Research limitations/implications– Though many of the proposed hypotheses were supported, results showed several interesting and unexpected findings. First, regarding the change agent role perception, people who perceived themselves as advocates displayed a higher level of intention to learn business skills than did those who identified with the other two roles (i.e. traditionalist and facilitator). Second, when compared to extrinsic learning motivation, intrinsic learning motivation contributed more to the intention to learn business skills. Third, the study contributes to the literature by finding that, in terms of direction and magnitude, the two types of self-efficacy have similar influence on an IS developer’s behavioral intention to learn business skills. Finally, work support was found to have a positive impact on both extrinsic and intrinsic learning motivation. However, it was interesting to note that work support did not lead to significantly higher levels of relative and absolute learning self-efficacy.Practical implications– The findings of this study provide several critical implications for practitioners seeking to encourage IS developers to learn b-skills. First, organizations should strongly encourage IS developers to take on the advocate role in ISD projects, and urge them to acquire business skills through formal education and on-the-job training. Second, organizations should also help IS developers understand how learning business skills is important for their future work and potential self-growth, rather than focusing solely on extrinsic benefits such as promotion or remuneration. Third, organizations can also make use of the strategies to enhance IS developer’s learning self-confidence and beliefs, which will, in turn, increase their intention to learn business skills. Finally, support from others is influential in the formulation of positive work attitudes and behaviors, so organizations will benefit when employees are well supported.Originality/value– While prior research has emphasized the importance of business skill possession for IS developers during the system development process, few studies have explored the factors affecting an IS developer’s behavioral intention to learn those business skills. This study intends to bridge this gap by investigating factors that drive IS developers’ intention to learn business skills. The findings of this study are useful to researchers in the development and testing theories related to IS developer learning behavior, and to practitioners to facilitate business skill learning for their IS development staff.

Emerging evidence suggests an association of Alzheimer's Disease (AD) with microglial and astrocytic dysregulation. Recent studies have proposed that activated microglia can transform astrocytes to a neurotoxic A1 phenotype, which has been shown to be involved in the promotion of neuronal damage in several neurodegenerative diseases, including AD. In the present study, we observed an obvious microglial activation and A1-specific astrocyte response in the brain tissue of APP/PS1 Tg mice. Fasudil treatment improved the cognitive deficits of APP/PS1 Tg mice, inhibited microglial activation and promoted their transformation to an anti-inflammatory phenotype, and further shifted astrocytes from an A1 to an A2 phenotype. Our experiments suggest Fasudil exerted these functions by inhibing the expression of TLR4, MyD88, and NF-κB, which are key mediators of inflammation. Using in vitro experiments, we further validated in vivo findings. Our cell experiments indicated that Fasudil induces a shift of inflammatory microglia towards an anti-inflammatory phenotype. LPS-induced microglia-conditioned medium promotes A1 astrocytic polarization, but Fasudil treatment resulted in a direct transformation of A1 astrocytes to A2. To summarize, our results show that Fasudil inhibits the neurotoxic activation of microglia and shifts astrocytes towards a neuroprotective A2 phenotype, representing a promising candidate for AD treatment.

Recent studies have shown that Nogo-A and the Nogo-A receptor affect β-amyloid metabolism and the downstream Rho GTP enzyme signaling pathway, which may affect the levels of β-amyloid and tau. Nogo-A may play a key role in the pathogenesis of Alzheimer's disease. However, the underlying molecular mechanisms of Fasudil treatment in Alzheimer's disease are not yet clear. Our results have found that Fasudil treatment for two months substantially ameliorated behavioral deficits, diminished β-amyloid plaque and tau protein pathology, and alleviated neuronal apoptosis in APP/PS1 transgenic mice. More importantly, two well-established markers for synaptic function, growth-associated protein 43 and synaptophysin, were upregulated after Fasudil treatment. Finally, the levels of Nogo-A, Nogo-A receptor complex NgR/p75NTR/LINGO-1 and the downstream Rho/Rho kinase signaling pathway were significantly reduced. These findings suggest that Fasudil exerts its neuroprotective function in Alzheimer's disease by inhibiting the Nogo-A/NgR1/RhoA signaling pathway.

Equipment is designed for detecting soft battery modules and is used for detecting whether the battery tab reaches its designated position. The system configuration requires visual positioning, a contact probe, a Cartesian robot connected to a host PC, a PLC controller, and C# software for language design. The system has characteristics including strong customization and simple operation.

While previous research has emphasised the importance of business skills for information systems IS developers in the process of IS development, few studies have investigated the determinants of IS developers’ behavioural intention to learn business skills. The current study explores the factors affecting IS developers’ intention to learn business skills based on previous theories and research. Data collected from 258 valid respondents are tested against the research model using the partial least-squares approach. The results indicate that both job involvement and career insight have significant positive effects on extrinsic and intrinsic motivations for learning business skills. Additionally, learning self-efficacy is not only found to have a significant influence on learning intention, but is also found to have a moderating effect on the positive relationship between intrinsic motivation and learning intention. The findings of this study provide several important theoretical and practical implications for IS developers’ behaviour of learning business skills.

The levitation control system is a key technique of the maglev system. Due to the strong non-linear character of the magnetic force, as well as the model uncertainties and external interferences of the maglev system, the Implicit General Predictive Control algorithm, which adjusts the parameters of the control scheme by using the input and output data, is adopted in this article. Taking the single electro-magnet levitation system as the research object, this algorithm not only guarantees the stability of the system, but also suppresses the vibration caused by the flexibility of the track. The advantages of this algorithm include: the superior control capacity, roll over optimization and little dependence on model. The simulation approves the validity of this method.

Square concrete-filled steel tubes (CFSTs) are gaining increasing usage in modern construction practice, offering improved mechanical properties and increased material efficiency compared with the individual steel and core concrete components. However, the cross-section slenderness of the encasing steel is, although more inflexible than a comparable hollow steel tube, restrained due to local buckling. A number of innovative kinds of reinforcement stiffeners have been put forward particularly for the square CFSTs with slender sections of encasing steel. To investigate the mechanical effect of the reinforcement stiffeners and compare them with traditional ones in practice, four square CFSTs welded with various reinforcement stiffeners and one reference CFST have been tested, and are presented in this paper. The mechanical behaviors such as the resistance, ductility and failure mode investigated during the test were also studied in the theoretical research, which was carried out to predict and summarize the comprehensive properties of the specimens.

In the system of preventing progressive collapse, the joints always play a key role in catenary action and alternate load path while the joints are usually under the combination of bending moment and tensional force. In this combination, high rotation capacity and good resistance of joints are demanded. In this paper, a new type of semi-rigid joint used in the structures with concrete-filled square steel tube (CFST) columns is proposed and developed by ABAQUS. The new type joint is suitable for the classification for semi-rigid connection; The bending moment resistance of the joint decreases linearly with the increase of tensional force; reducing pretension force reasonably is beneficial for the tensional force to develop “catenary action”; the width of short leg of angle would influence the moment resistance of the joint evidently; the initial rotation stiffness is not affected by width of leg dramatically.

Given that e-tailing service failure is inevitable, a better understanding of how service failure and recovery affect customer loyalty represents an important topic for academics and practitioners. This study explores the relationship of service failure severity, service recovery justice (i.e., interactional justice, procedural justice, and distributive justice), and perceived switching costs with customer loyalty; as well, the moderating relationship of service recovery justice and perceived switching costs on the link between service failure severity and customer loyalty in the context of e-tailing are investigated. Data collected from 221 useful respondents are tested against the research model using the partial least squares (PLS) approach. The results indicate that service failure severity, interactional justice, procedural justice and perceived switching costs have a significant relationship with customer loyalty, and that interactional justice can mitigate the negative relationship between service failure severity and customer loyalty. These findings provide several important theoretical and practical implications in terms of e-tailing service failure and recovery.

Cornstalk fibers were modified with surface modification and the properties of cornstalk fiber/gypsum composites was studied. The results showed that mechanical properties of cornstalk fiber/gypsum composites were enhanced by adding unmodified cornstalk fibers, but composites waterproof performance was decreased greatly. Through surface modification on cornstalk fibers, composites mechanical properties were further enhanced, and composites waterproof performance was improved obviously. The mechanism of surface modification was discussed, and the model of interfacial zone between modified cornstalk fiber and gypsum matrix was proposed.

In this paper, a 9-storey Benchmark frame model was used to analyze the response of joints due to sudden column loss. On the basis of the substructure model, the static and dynamic nonlinear analyses were conducted seriatim using the alternative path method. It is found that the removals of the ground columns bring high-level joint moments and mild increasing of axial forces. In particular, the removal of side column with pin-ended connection results in the largest vertical displacement of adjacent joint and increase the flexural demands to the next joint. For this model, the most critical case appears at the failure of hinged side column, the next is the rigid side column.

Physical modification and chemical modification were used to modify fluorgypsum. Effect of physical modification and chemical modification on the performance of fluorgypsum was studied, and the mechanism of modification was discussed by testing the phase composition and microstructure of modified fluorgypsum, using XRD and SEM. The results showed that fluorgypsum activity was excited effectively by physical modification and chemical modification. Physical modification decreased CaSO4 grain size and structure regularity, and increased fluorgypsum specific surface area, and the optimum specific surface area was 4600-4900cm2/g. Chemical modification accelerated fluorgypsum hydration and CaSO4•2H2O growth, and increased CaSO4•2H2O grain size and slenderness ratio. The strength of fluorgypsum was exerted effectively by chemical modification.

In order to improve the mechanical performance of straw fiber reinforced gypsum composite materials, corn straw fiber was modified by alkaline treatment and chemical coating treatment, the influence of different surface modification treatment on mechanical performance of gypsum composite material was studied, and the mechanism of surface modification was discussed. The results indicated that: surface modification treatments could improve the interfacial bonding between straw fiber and desulfurization gypsum, and enhance mechanical performance of composite materials; comparing different treatments, the acrylic chemical coating treatment could enhance the strength of composite materials more outstandingly than other treatments.

Heavy-duty cast steel universal hinged supports are gaining increasing usage in modern large-span structures, offering extremely large individual load carrying capacity and universal rotation ability which is preferable to release temperature effects and to improve force conditions of lower structures. This paper presents a full-scale experimental study and elastic-plastic finite element (FE) analysis on the performance of an innovative heavy-duty cast steel support. The support is composed of three main components, i.e. an upper one, a lower one and an intermediate rotation pad. External loads are designed to be passed and transferred through the contact interaction of the three casting parts. The support studied in this paper is expected to possess a higher capacity than existing supports while having the ability of universal rotation under heavy loads. Three full-scale static experiments corresponding to three typical load cases (i.e. tension-shear load case, compression-shear load case, and shear-tension load case, respectively) have been carried out employing a multifunctional loading device. A three-dimensional FE model was developed using the commercial software ANSYS, considering the contact behavior between the support components and accounting for both material and geometrical nonlinearities. The model was validated against the experimental results reported in this paper. The performance of this support was evaluated in accordance with a Chinese national code ‘Technical specification for application of connections of structural steel casting (CECS 235:2008)’. This study concluded that this type of support performs well and that it could be used for realistic applications.

Concrete-filled special-shaped (L-shaped, T-shaped, and cross-shaped, and etc.) steel tube column is a type of member in which concrete is poured into special-shaped steel tube so that steel and concrete support loads together. It improves the seismic behaviors of reinforced concrete special-shaped columns due to the better confining effects provided by the steel tube. A test research on the seismic behaviors of one concrete-filled T-shaped steel tube column with pseudo static method is presented and the load-displacement curve and skeleton curve are provided. Series of steel bar stiffeners were welded onto the steel tube in order to postpone the buckling of steel tube and to enhance confining effects. A numerical analysis program was developed using a fiber-based method. The constitutive model of concrete employed the modified Mander model, and that of steel employed a bi-linear model considering the Bausinger effect. The numerical analysis program was verified by the test results and parametric analysis was carried out, in which the influences of the ratio of axial compression stress to strength, steel tube thickness and concrete strength were mainly discussed. The following conclusions are obtained: with the increase of the ratio of axial compression stress to strength, the bearing capacity of member increases and the energy dissipation capacity improve, while the ductility deteriorates. With the increase of steel tube thickness, the initial rigidity, bearing capacity, ductility and energy dissipation capacity improves simultaneously. With the increase of concrete strength, the bearing capacity increases, the energy dissipation capacity improves, while the ductility deteriorates.

Separation of binary amino acids from aqueous solutions by solvent extraction (SX) and liquid surfactant membrane (LSM) was compared, in which the acidic extractant di(2-ethylhexyl)phosphoric acid (D2EHPA) was selected as an active carrier. The distribution ratios were measured by batch SX experiments. Important variables affecting LSM permeation experiments, including the pH in the aqueous external phase, surfactant concentration, the volume ratios of W/O emulsions to aqueous external phase and that of organic to aqueous internal phases, and HCl concentration in the internal phase, were systematically studied. It was shown that the separation was promising only when the amino acids had sufficiently different isoelectric points. Compared to batch SX results, the optimal pH for effective separation shifted to a lower level and the selectivity was enhanced in LSM process, which was a result of the counter transport of hydrogen ions.