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Blueberry contains bioactive compounds which are beneficial to organisms, such as phenolics and flavonoids. The purpose of this paper is to evaluate the potential protective effects of blueberry extracts (BE) on H₂O₂-induced HepG2 cells.

Cell protection was evaluated via the survivals of the cell. Reactive oxygen species (ROS) level, antioxidant enzyme and malondialdehyde (MDA) were detected. Western blot was carried out to analysis protein which was related to the cell apoptosis pathway. Changes in morphology including: cell total apoptosis/necrosis and G0/G1 cycle arresting were also concomitant.

The levels of ROS and malondialdehyde (MDA) reduced after the BE treatment while the contents of superoxide dismutase, and glutathione peroxidase (GSH-Px) increased in HepG2 cells induced by H2O2. Furthermore, mechanistic studies indicated that BE regulated the activation of mitochondrial apoptosis signal-regulating (Bcl-2, Bax). Qu was used as a positive control group. All these results demonstrated that the BE have a potential against oxidative stress in vitro.

Few studies have focused on the bioactivities of blueberry on oxidative stress. Taken together, the results confirm that polyphenol-enriched BE have the ability to protect against oxidative stress in cells. It has a great potential as a functional food ingredient to health benefits. Furthermore, this work showed the value of using simple biological models to screen for compounds that are of interest for food and pharmacological industry.

The purpose of this paper is to describe the design and development of “Pylon-Climber II”, a 5-DOF biped climbing robot (degree of freedom – DOF) for moving on the external surface of a tower and assisting the electricians to complete some maintenance tasks.

The paper introduces a pole-climbing robot, which consists of a 5-DOF mechanical arm and two novel grippers. The gripper is composed of a two-finger clamping module and a retractable L-shaped hook module. The robot is symmetrical in structure, and the rotary joint for connecting two arms is driven by a linear drive mechanism.

The developed prototype proved a new approach for the inspection and maintenance of the electricity pylon. The gripper can reliably grasp the angle bars with different specifications by using combined movement of the two-finger clamping module and the retractable L-shaped hook module and provide sufficient adhesion force for the Pylon-Climber II.

The clamping experiments of the gripper and the climbing experiments of the robot were carried out on a test tower composed of some angle bars with different specification.

This paper includes the design and development of a 5-DOF biped climbing robot for electricity pylon maintenance. The climbing robot can move on the external surface of the electric power tower through grasping the angle bar alternatively. The gripper that is composed of a two-finger gripping module and a retractable L-shaped hook module is very compact and can provide reliable adhesion force for the climbing robot.

The purpose of this paper is to untangle the impacts of a firm’s corporate reputation and its alliance partners’ social capital on its financial performance, drawing on the relational and the network points of view.

This paper explored the moderating effect of corporate reputation on the relationship between partners’ social capital (e.g. resource heterogeneity, structural relations and partners’ social ties) and a focal firm’s performance. An OLS three-step regression model (controls, main effects and interaction effects) was used to test the proposed hypotheses based on 265 US joint ventures.

The influence of partners’ social capital on a focal firm’s performance is negatively moderated by the focal firm’s reputation at the firm and network levels; larger and more prestigious firms listed in Fortune database tend to choose partners with a higher level of resource heterogeneity, whereas smaller firms tend to choose partners in similar industries to increase economies of scale. The social capital factors of the partners will have different effects on the focal firm performance.

The value of this paper is in providing insight into the importance and nuances of corporate reputation in offsetting the advantages of inter-firm alliances and their impact on firm performance. In particular, the performance benefits of inter-firm alliance partners’ social ties and heterogeneous resources are negatively affected by the corporate reputation of a firm.

The former residences of historical figures are typical landscape elements of historic districts, which are characterised by the styles of these residences and spiritual historical figures cultures. The purpose of this paper is to determine how the former residences respond once the historical figures living there have passed.

The history of human culture and progression of urban construction – which are submerged in societal transformation – is recorded for old Beijing city. Narrative space theory is used and methods such as a content analysis, map overlay and the Geographic Information System are employed to analyse the selected 300 former residences of historical figures in old Beijing city.

The results are as follows: the political setting played a key role in the evolution process, three political narrative areas in the inner city and one cultural narrative area in the outer city form the narrative spatial structure of the former residences of historical figures, “government construction” and “resident construction” are the main reasons for the loss and destruction of narrative spaces and ordinary life is an important channel for showcasing the history of former residences. The narrative spaces of these residences carry double histories, namely, the development of human history and of city construction.

Different from former studies that focus on the preservation of the single historical building, this study explores the integral logic of historic buildings in the whole city through narrative space theory to get a combination of culture and space.

This paper aims to present an unconditionally energy-stable scheme for approximating the convective heat transfer equation.

The scheme stems from the generalized positive auxiliary variable (gPAV) idea and exploits a special treatment for the convection term. The original convection term is replaced by its linear approximation plus a correction term, which is under the control of an auxiliary variable. The scheme entails the computation of two temperature fields within each time step, and the linear algebraic system resulting from the discretization involves a coefficient matrix that is updated periodically. This auxiliary variable is given by a well-defined explicit formula that guarantees the positivity of its computed value.

Compared with the semi-implicit scheme and the gPAV-based scheme without the treatment on the convection term, the current scheme can provide an expanded accuracy range and achieve more accurate simulations at large (or fairly large) time step sizes. Extensive numerical experiments have been presented to demonstrate the accuracy and stability performance of the scheme developed herein.

This study shows the unconditional discrete energy stability property of the current scheme, irrespective of the time step sizes.

At present, piezoelectric impedance technology has been used in the study of wood damage monitoring. However, little effort has been made in the research on the application of piezoelectric impedance system to monitor the change of wood moisture content (MC). The monitoring method of wood MC is used by piezoelectric impedance technique in this study.

One piezoceramic transducer is bonded to the surface of wood specimens. The MC of the wood specimens increases gradually from 0% to 60% with 10% increments; the mechanical impedance of the wood specimen will change, and the change in the mechanical impedance of the structure is reflected by monitoring the change in the electrical impedance of lead zirconate titanate. Therefore, this paper investigates the relationship between wood MC change and piezoelectric impedance change to verify the feasibility of the piezoelectric impedance method for monitoring wood MC change.

The experiment verified that the real part of impedance of the wood increased with the increase of wood MC. Besides, the damage index root mean square deviation is introduced to quantify the damage degree of wood under different MC. At the same time, the feasibility and validity of this experiment were verified from the side by finite element simulation. Finally, MC monitoring by piezoelectric impedance technique is feasible.

To the best of the authors’ knowledge, this work is the first to apply piezoelectric ceramics to the monitoring of wood MC, which provides a theoretical basis for the follow-up study of a wide range of wood components and even wood structure MC changes.

Fall accidents can cause casualties and economic losses in the construction industry. Fall portents, such as loss of balance (LOB) and sudden sways, can result in fatal, nonfatal or attempted fall accidents. All of them are worthy of studying to take measures to prevent future accidents. Detecting fall portents can proactively and comprehensively help managers assess the risk to workers as well as in the construction environment and further prevent fall accidents.

This study focused on the postures of workers and aimed to directly detect fall portents using a computer vision (CV)-based noncontact approach. Firstly, a joint coordinate matrix generated from a three-dimensional pose estimation model is employed, and then the matrix is preprocessed by principal component analysis, K-means and pre-experiments. Finally, a modified fusion K-nearest neighbor-based machine learning model is built to fuse information from the x, y and z axes and output the worker's pose status into three stages.

The proposed model can output the worker's pose status into three stages (steady–unsteady–fallen) and provide corresponding confidence probabilities for each category. Experiments conducted to evaluate the approach show that the model accuracy reaches 85.02% with threshold-based postprocessing. The proposed fall-portent detection approach can extract the fall risk of workers in the both pre- and post-event phases based on noncontact approach.

First, three-dimensional (3D) pose estimation needs sufficient information, which means it may not perform well when applied in complicated environments or when the shooting distance is extremely large. Second, solely focusing on fall-related factors may not be comprehensive enough. Future studies can incorporate the results of this research as an indicator into the risk assessment system to achieve a more comprehensive and accurate evaluation of worker and site risk.

The proposed machine learning model determines whether the worker is in a status of steady, unsteady or fallen using a CV-based approach. From the perspective of construction management, when detecting fall-related actions on construction sites, the noncontact approach based on CV has irreplaceable advantages of no interruption to workers and low cost. It can make use of the surveillance cameras on construction sites to recognize both preceding events and happened accidents. The detection of fall portents can help worker risk assessment and safety management.

Existing studies using sensor-based approaches are high-cost and invasive for construction workers, and others using CV-based approaches either oversimplify by binary classification of the non-entire fall process or indirectly achieve fall-portent detection. Instead, this study aims to detect fall portents directly by worker's posture and divide the entire fall process into three stages using a CV-based noncontact approach. It can help managers carry out more comprehensive risk assessment and develop preventive measures.

The purpose of this paper is to describe the design and development of “Pylon-Climber”, a pole climbing robot (PCR) for climbing along the corner columns of electricity pylon and assisting the electricians to complete maintenance tasks.

Introduces a PCR that is composed of a simple climbing mechanism and two novel grippers. The gripper consists of two angle-fixed V-blocks, and the size of V-block is variable. The clamping method of the angle bar meets the requirement of the force closure theorem. The whole design adopts symmetrical design ideas.

The developed prototype proved possibility of application of PCRs for inspection and maintenance of pylon. The novel gripper can provide enough adhesion force for climbing robot.

The robot is successfully tested on a test tower composed of different specification steel angles, oblique ledges and overlapping steel struts.

Design and development of a novel climbing assistive robot for pylon maintenance. The robot is able to climb along the column of electricity pylon and pass all obstacles. The gripper can reliably grasp the angle bar with different specification and overlapping steel struts from multiple directions.

The purposes of this paper are: to examine the adoption of corporate social responsibility (CSR) strategies related to environment protection by Chinese state oil companies; and to analyze the effects of global competitions and cooperation on the CSR adoption processes.

Based on a content analysis of 58 corporate reports and three interviews with senior managers from Chinese-Western joint ventures, the authors analyzed the environmentally-related CSR adoption strategies and the effects of global competition and cooperation in Chinese state oil companies.

The findings suggest that more cooperative CSR strategies related to environment protection have been adopted by Chinese state oil companies in the past decade. The main reasons are: the force of international and local environmental regulations; the pressures from partners of western oil companies and the desire to increase the global competitive advantage of the Chinese state oil companies.

Given that this study is based only on the analysis of corporate reports and three interviews, the authors' conclusions should be considered preliminary and inconclusive. Future studies should be done to collect more primary data by interviewing and surveying by questionnaire a significant number of managers from these companies to validate these conclusions.

This paper highlights the adoption of CSR strategies by three Chinese state oil companies and the effects of global operations which have been little studied academically so far.

Drawing on the contingency perspective of leadership, the purpose of this paper is to examine the relation between transactional leadership and team innovativeness by focusing on the moderating role of emotional labor and the mediating role of team efficacy. The authors propose and empirically test the hypothesis that the relation between transactional leadership and team innovativeness is negative when the level of emotional labor is high whereas the relation is positive when the level of emotional labor is low. The authors further examine the process mechanism of this interactive effect by testing the mediating role of team efficacy.

In total, 90 Chinese work teams, comprising 462 members and 90 team leaders, were surveyed. Hierarchical regression analyses were performed and moderated causal steps approach applied to test the authors' mediated moderation model.

As predicted, transactional leadership was negatively associated with team innovativeness when emotional labor was high whereas the association was positive when emotional labor was low. Team efficacy mediated the interactive effects of transactional leadership and emotional labor on team innovativeness.

The paper contributes to the contingency perspective on transactional leadership and team innovativeness by identifying emotional labor as an important moderator and team efficacy as a critical mediator, yet methodological limitations do exist in the study. Although data were collected from multiple sources to avoid common method variance, the design was cross‐sectional, which limits the authors' ability to make robust inferences of causality.

By examining both the moderating and mediating effects, the paper contributes to uncovering the black box in which transactional leadership exerts an influence on team innovativeness.