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In this study, a novel glutathione (GSH) surface molecular imprinting polymer (SMIP) was successfully prepared by using macroporous adsorption resins (MAR) as substrate, which could separate and purify GSH efficiently.

SMIP was synthesized by chloromethylated modified MAR (LX1180-Cl) as the substrate, N, N’-methylenebisacrylamide (NMBA) as a crosslinker, GSH as a template, acrylamide (AM) and N-vinylpyrrolidone (NVP) as functional monomers. The morphology and structure of the polymer were characterized by scanning electron microscope and Fourier transforms infrared spectroscopy.

The maximum adsorption capacity toward GSH was 39.0 mg/g and the separation decree had relation to L-cysteine (L-cys) was 4.2. The optimal operation conditions were studied in detail and the got as follows: the molar ratios of NMBA, AM, GSH and NVP, were 7.0, 0.8 and 0.5. The optimal time and temperature were 14 h and 40°C, respectively. The Langmuir and pseudo-first-order model were fitting these adsorption characteristics well.

GSH has a diversity of medicinal and bioactive functions, so the purpose of this study representing a method in separate and purify technology of GSH, which provided a way for the development of medicine.

This contribution provided a novel way to separate GSH from L-cys. Under the optimal conditions, the maximum adsorption capacity toward GSH was 39.0 mg/g and the separation decree had relation to L-cys was 4.2.

This paper aims to evaluate the separation and purification characteristics of flavonoids from polygonum cuspidatum (PC) extracts by using macroporous adsorption resins (MAR) mixed bed to improve the utilization rate of flavonoids.

Taking the separation performance of flavonoids as an evaluation index, the best MAR were screened from 31 sorts of MAR and combined the best MAR to form a MAR mixed bed for adsorption and separation of flavonoids.

By studying the separation conditions that affect flavonoids, the results showed that resin LZ-72 has best separation and purification effect on flavonoids under the optimal adsorption and desorption conditions, the purity of the obtained flavonoid compound reaches 82.50%, 2.66 times of the initial extract, and the recovery rate reaches 89.70%. Theoretical research results have shown that the adsorption of flavonoids by MAR conforms to the pseudo-second-order kinetics and Freundlich models.

Because the flavonoids in PC have great medicinal value, the purpose of this work is to develop a method of separating and purifying flavonoids from PC, which will provide a certain foundation for the development of medicine.

This contribution provided a novel way to separate flavonoids from PC. Under the optimal conditions, the content of flavonoids in the product was increased 2.66-fold from 31.01% to 82.50%, and the recovery yield was 89.70%.

The purpose of this study is to examine whether banks’ commitment to corporate social responsibility (CSR) is related to the diversification of their activities and whether CSR, as a result, affects banks’ risk profile.

Using a sample of 215 publicly traded U.S. bank holding companies between 1996 and 2016, this study applies regression analysis to examine the links between CSR and activity diversification and risk-taking. It also conducts a mediation test to determine whether CSR affects risk through its influence on banks’ activity diversification.

The results of this study show that banks engaging in positive CSR activities significantly increase the diversification of their banking activities, consistent with the theory that CSR serves as an implicit risk hedging strategy. Mediation analysis provides evidence that this translates into more stable and less risky banks.

This study contributes to the literature by suggesting that activity diversification is a channel through which CSR reduces bank risk and improves asset quality.

This study aims to research the development trend, research status, research results and existing problems of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

Based on the investigation and analysis of the development history, structure form, structural parameters, stress characteristics, shear connector stress state, force transmission mechanism, and fatigue performance, aiming at the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge, the development trend, research status, research results and existing problems are expounded.

The shear-compression composite joint has become the main form in practice, featuring shortened length and simplified structure. The length of composite joints between 1.5 and 3.0 m has no significant effect on the stress and force transmission laws of the main girder. The reasonable thickness of the bearing plate is 40–70 mm. The calculation theory and simplified calculation formula of the overall bearing capacity, the nonuniformity and distribution laws of the shear connector, the force transferring ratio of steel and concrete components, the fatigue failure mechanism and structural parameters effects are the focus of the research study.

This study puts forward some suggestions and prospects for the structural design and theoretical research of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

This paper aims to present a direct analysis to demonstrate why markedly different tensile and compressive behaviors of concretes could not be simulated with the Drucker–Prager yield criterion.

This study proposed an extended form of the latter for establishing a new elastoplasticity model with evolving yield strengths.

Explicit closed-form solutions to non-symmetric tensile and compressive responses of uniaxial specimens at finite strain are for the first time obtained from hardening to softening.

With such exact solutions, the yield strengths in tension and compression can be explicitly prescribed by uniaxial tensile and compressive stress-strain functions. Then, the latter two are further provided in explicit forms toward accurately simulating tensile and compressive behaviors. Numerical examples are supplied for meso-scale heterogeneous concrete (MSHC) and high-performance concrete (HPC), etc. Model predictions are in good agreement with test data.

Users' knowledge contribution behaviors are critical for online Q&A communities to thrive. Well-organized question threads in online Q&A communities enable users to clearly read existing answers and their evaluations before contributing. Based on the social comparison and peer influence literature, the authors examine peer influence on the informativeness of knowledge contributions in competitive settings. The authors also consider three levels of moderating factors concerning individuals' perception of competitiveness: question level, thread level and contributor level.

The authors collected data from one of the largest online Q&A communities in China. The hypotheses were validated using hierarchical linear models with cross-classified random effects. The generalized propensity score weighting method was employed for the robustness check.

The authors demonstrate the peer influence due to social comparison concerns among knowledge contribution behaviors in the same question thread. If more prior knowledge contributors choose to contribute long answers in the question thread, the subsequent contributions are more informative. This peer influence is stronger for factual questions and questions with higher popularity of answering but weaker in recommendation-type and well-answered questions and for contributors with higher social status.

This research provides a new cue of peer influence on online UGC contributions in competitive settings initiated by social comparison concerns. Additionally, the authors identify three levels of moderating factors (question level, thread level and contributor level) that are specific to online Q&A settings and are related to a contributor's perception of competitiveness, which affect the direct effect of peer influence on knowledge contributions. Rather than focus on motivation and quality evaluation, the authors concentrate on the specific content of online knowledge contributions. Peer influence here is not based on an actual acquaintance or a following relationship but on answering the same question. The authors also illustrate the competitive peer influence in subjective and personalized behaviors in online UGC communities.

This research investigates consumer intention to follow online community advice. Applying the technology acceptance model (TAM) to the context of online restaurant communities, the study empirically examines the effects of perceived usefulness, perceived ease of use, attitude and trust on the intention to follow online advice.

The data were collected from 360 members of online restaurant communities on Facebook and analyzed using structural equation modeling (SEM).

The findings revealed that trust, perceived usefulness and attitude are key predictors of the intention to follow online restaurant community advice.

Extant research on the influence of online reviews on consumer behavior in the restaurant industry has largely focused on the characteristics of the review, reviewers or readers. Moreover, other studies have investigated consumers' motivations to write online restaurant reviews. This study, however, takes a different approach and examines what drives consumers to follow the advice from online restaurant communities.

Hand, foot and mouth disease (HFMD) is a common infectious disease in infants and children. HFMD has caused millions of cases and a large epidemic worldwide. A number of studies have shown that the incidence of HFMD is closely related to various factors such as meteorological factors, environmental air pollution factors and socio-economic factors. However, there are few studies that systematically consider the impact of various factors on the incidence of HFMD. The paper aims to discuss these issues.

This study used grey correlation analysis and principal component analysis (PCA) method to systematically analyse the impact of meteorological factors, health resource factors, socio-economic factors and environmental air pollution factors on the incidence of HFMD in Shenzhen.

The incidence of HFMD in Shenzhen was affected by multiple factors. Grey correlation analysis found eight influencing factors which are as follows: volume of industrial waste gas emission; the days of air quality equal to or above grade; the volume of industrial nitrogen oxide emission; precipitation; the mean air temperature; the gross domestic product; the expenditure for medical and health care; and the gross domestic product per capita. PCA found that the gross domestic product, the volume of industrial soot emission, the relative humidity, and the days of air quality equal to or above grade have a higher load value.

This study is the one of the first studies that apply the grey correlation analysis to analyse the influencing factors of HFMD in the English literature, which to some extent fills up the blank in this field.

This paper aims to study previously prepared and fully characterized chitosan nanoparticles (CNPs) as a starting substrate and microwave initiation technique for grafting acrylic acid (AA). This was done to see the influence of both CNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability, biocompatibility and reactivity and microwave initiation technique with respect to reduction in organic solvents, toxic chemical initiator and exposer time on exploiting the graft yield % and enhancing water solubility and antibacterial properties.

For evaluating the best accurate standard metrological method for calculating the graft yield %, the grafting parameters were stated in terms of graft yield percent and measured gravimetrically (based on dry weight method) and titrimetrically (based on carboxyl content). Microwave power, AA and CNPs concentrations and reaction duration were shown to be the most important parameters influencing the grafting process.

The optimum reaction conditions were obtained when CNPs 1.5 g, AA 150 bows, microwave irradiation power 500 W and reaction duration 120 s were used. Various analytical methods were used to characterize CNPs and poly(AA)–CNPs graft copolymers. According to the findings, Fourier transform infrared spectroscopy examination determines the attachment of carboxyl groups to CNPs chains. The thermogravimetric analysis revealed that the copolymers were more thermally stable than CNPs counterparts. Furthermore, the resulting copolymers were shown to have greater water solubility biodegradability resistance and antibacterial properties than CNPs counterpart. Finally, a preliminary mechanism demonstrating all occasions that occur during the polymerization reaction has been proposed.

The advancement addressed here is undertaken using previously prepared and fully characterized CNPs as a green bio-nanocompatible polymer and microwave initiation technique as green and efficient tool with respect to reduction in organic solvents toxic chemical initiator and exposer time for grafting AA.

Beyond a mandated use, rationales behind executive choice to accept or reject building information modelling (BIM) are ambiguous. BIM acceptance is complex for organisations, and existing decision-making models are impractical to make realistic choices. A practical solution must assist a holistic reflection of internal and external BIM success factors. Nevertheless, extant literature is largely focused on software use and awareness. Thus, this paper aims to suggest a novel framework for assessing firm readiness, aimed at facilitating BIM uptake.

Extant explanatory studies are inadequate in assessing the soft nature of BIM uptake. Thus, a design science research was employed as an alternative methodology. A means-end analysis was utilised for solution incubation, and cross-disciplinary reasoning, the strategy to establish valid solutions on firm readiness. Previous studies were reviewed on BIM, technology acceptance (generally) and complexity.

“Technology attitude” is presented as involving more holistic variables than a simplistic reliance on software use to mirror BIM acceptance. Technology acceptance model (TAM) is appropriate to explain BIM attitude attributes, but its current use is sub-optimal. Selective information processing and unconscious thought theory were integrated into TAM to explain attitude formation from multiple perspectives, resulting in a novel BIM attitude scale (BIMAS). Upon verification, the proposed framework will facilitate an objective authentication of biases that associate with BIM acceptance.

Whilst BIM readiness is assessed largely with a primary focus on theory building, practical relevance must be at the forefront of BIM development. This study articulates that design science research can enhance the practical relevance of BIM adoption models. BIM acceptance attitude must be assessed through a verified scale contrary to the assessment of self-biases of executives in literature. BIMAS suggests a testable solution for this. Theory building research must be the future focus to enhance the relevance of this initial solution.