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Construction industries have significant impacts on the economy, society and environment. To transform construction industry towards sustainability, construction enterprises' perceptions and performance on sustainability needs to be understood and evaluated, which has not be fully explored by existing studies. This paper holistically examines the Chinese construction enterprises’ attitude towards and performance on various aspects of sustainability (e.g. the economic, social and environmental aspects) in order to identify those aspects the firms perceive to be the most and least important and those aspects the firms perform best and worst on. The associations among the sustainability attitude, sustainability performance, and firm size are also explored. The findings show that quality management and customer service are perceived as the most important as well as the best-performed aspects by the firms while supporting community development is the least important and worst-performed aspect. Sustainability attitude is positively correlated with performance, and larger firms tend to have better sustainability performance than that of small ones. However, larger construction firms do not necessarily perceive sustainability more important. This study provides a useful reference for policy makers and researchers to understand how sustainability is perceived and implemented by the Chinese construction firms.

Sustainability has become a critical perspective in managing firms via a holistic approach by considering economic, environmental and social dimensions of firms. With the rising significance of sustainable development, the theories of sustainability in firms have evolved during the past six decades. This article offers a critical review of the evolving theories linking sustainability to firms, and discusses their implications for future renewable energy research. The relationships among different theories are critically analysed, and the directions for future research are discussed. The paper shows that, the main theories linking sustainability to firms, in a chronological order, are: 1) Corporate Social Responsibility, 2) Stakeholder Theory, 3) Corporate Sustainability, and 4) Green Economics. Currently various innovative approaches and new theories emerged, such as Co-evolution Theory and Multi-level Perspective, reflecting three directions of theory development, namely 1) shifting from “what” to “how”, 2) growing use of interdisciplinary approach, and 3) towards broader systems. Renewable energy studies associated with firms and future research opportunities in this area are also critically analysed. The comprehensive review offered in this paper provides a useful reference for policy makers, corporate managers and researchers interested in corporate sustainability and renewable energy related studies.

Chronic stressors represented risk factors for the etiology or exacerbation of several gastrointestinal diseases. The goal of the present study was to examine whether chronic restraint stress (CRS) could initiate and aggravate colonic inflammation, integrity damage and metabolic disturbance of rats. Firstly, increased inflammatory cytokines (interferon-γ (IFN-γ), tumor necrosis factor-α(TNF-α) and interleukin-10(IL-10)) and decreased tight junction (TJ) proteins (occludin and zonula occludins-1 (ZO-1)) in rat colon were observed. Secondly, untargeted metabolomics based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass (UPLC-Q-TOF/MS) revealed that TRP metabolism was the most prominently affected. Thirdly, quantification of TRP and its metabolites via prominence ultrafast liquid chromatography coupled with a QTRAP 5500 mass (UFLC-QTRAP-5500/MS) showed that TRP, kynurenine (KYN), kynurenic acid (KA) and 3-hydroxykynurenine (3-HK) were significantly increased. At the same time, 5-hydroxytryptamine (5-HT) was unchanged and 5-hydroxyindolacetic acid (5-HIAA) was significantly decreased in the colon of CRS rats. Besides, TRP metabolic enzyme changes were with the same trends as the corresponding metabolites. Thus, our data showed that CRS could initiate colonic inflammation, integrity damage and colonic metabolism disturbance, especially TRP-KYN metabolism pathway of rats, which may provide an experimental background for future research on stress-related gastrointestinal dysfunction. SIGNIFICANCE: Chronic exposure to psychological stress could induce metabolic imbalance of the body, and stressful life events were intimately correlated with frequent relapses in patients with intestinal disorders. The present study showed that chronic restraint stress (CRS) could initiate and aggravate colonic inflammation, integrity damage and metabolic disturbance, especially tryptophan-kynurenine metabolism of rats. Tryptophan-kynurenine pathway may be involved in the initiation and development of diseases induced by chronic stress. This research may shed light on future research on stress-related gastrointestinal dysfunction.

A new method for the determination of platelet-derived growth factor BB (PDGF-BB) was developed using an electrochemical immunosensor with an aptamer-primed, long-strand circular detection probe. Rabbit anti-human PDGF-B polyclonal antibody was immobilized on the electrode to serve as the capture antibody. The detection probe was synthesized via polymerase extension along a single-stranded circular plasmid DNA template with a primer headed by the anti-PDGF-B aptamer. In the presence of the analyte, the aptamer-primed circular probe was captured on the electrode via the formation of an antibody/PDGF-BB/aptamer sandwiched complex. The electroactivity indicator methylene blue was adsorbed on the electrode surface via the analyte-sandwiched complex with long-strand circular DNA, thus yielding a strong electrochemical signal for the quantification of PDGF-BB. This strategy allowed electrochemical detection with enormous signal amplification arising from the long-strand localized circular probe. The oxidation peak current of methylene blue in square wave voltammetric measurements showed a linear dependence on the concentration of PDGF-BB in the range from 50 to 500 ng mL(-1), with a detection limit as low as 18 pg mL(-1).