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Fibrinolytic enzymes are important thrombolytic agents for blood-clotting disorders like cardiovascular diseases. Availability of novel recombinant fibrinolytic enzymes can overcome the shortcomings of current thrombolytic drugs. With the objective of facilitating their cost-effective production for therapeutic applications and for gaining deeper insight into their structure-function, we have cloned and expressed the first fibrinolytic protease gene from Cordyceps militaris. Cordyceps militaris fibrinolytic enzyme (CmFE) has one open reading frame of 759 bp encoding “pre-pro-protein” of 252 amino acids. Recombinant CmFE was expressed as 28 kDa extracellular enzyme in Pichia pastoris which was capable of degrading fibrin clot. A structure homology model of CmFE was developed using urokinase-type plasminogen activator. The active site contains catalytic triad His41, Asp83, Ser177 and consensus sequence of GDSGG. The substrate binding residues are Asp (171), Gly (194) and Ser (192). Its trypsin-like specificity is determined by the critical Asp171 in S1 subsite. The “oxyanion hole” is formed by backbone amide hydrogen atoms of Gly-175 and Ser-177. CmFE contains six conserved cysteines forming three disulfide linkages. This is the first study describing cloning, expression and prediction of structure-function relationship of a mushroom fibrinolytic protease. Hence it has great relevance in application of fibrinolytic enzymes as thrombolytic agents.

Construction is a major contributor to pollution in the natural environment. Among all construction pollutants, construction dust is the most significant pollutant that endangers human health. To expand the limited scope of studies on construction dust exposure, this study investigates current dust control practices in the construction industry in Hong Kong through dust monitoring data compilation. The database constructed and compiled by this study is larger than any other previous dust-related datasets in the construction industry in Hong Kong. A total of 837 samples are collected from 33 construction sites and 16 contractors, among which 783 valid samples are analyzed. Descriptive statistics are reported in terms of “construction process”, “trade”, “tools”, “data source type”, and “dust control measure”. Overall geometric mean for personal exposures are 0.314 (geometric standard deviations: 3.929) mg/m3 for respirable dust and 0.003 (geometric standard deviations: 5.105) mg/m3 for quartz concentration. It is found that the top three dust respirable exposures are from cement mixing, concrete breaking, and manual demolition, whereas grinding and rock breaking are recorded the two highest processes in terms of quartz exposure. Analytical results indicate that respiratory protection commonly used on construction sites is often inadequate for exposures encountered. Data variability within task and tool is large, with high exposures reported for a broad spectrum of tools. This study attains a large dataset to represent as many dust production construction activities as possible, determining the most influential factors for predicting dust exposure and evaluating the effectiveness of current dust control practices. This knowledge should, in turn, lead to enhanced practices of dust control in Hong Kong and highlight areas that need improvements.

Emerging advanced technologies (EAT) have been regarded as significant technological innovations which can greatly improve the transforming construction industry. Given that research on EAT related to the management of prefabricated construction (MPC) has not yet been conducted, various researchers require a state-of-the-art summary of EAT research and implementation in the MPC field. The purpose of this paper is to provide a systematic literature review by analysing the selected 526 related publications in peer-reviewed leading journals during 2009–2020. Through a thorough review of selected papers from the state-of-the-art academic journals in the construction industry, EAT is recognised as the key area affecting the development of the MPC discipline. This study has value in offering original insights to summarise the advanced status quo of this field, helping subsequent researchers gain an in-depth understanding of the underlying structure of this field and allowing them to continue future research directions.

Prefabricated housing construction (PHC) will be widely recognized as a contributor to consumption reduction and sustainability enhancement if inherent drawbacks (e.g., fragmented management, poor connectivity) can be addressed efficiently. The promotion of advanced information and communication technologies (ICT) has triggered the evolvement of smart product-service systems (SPSS), where a smart connected product (SCP) acts as a critical role in the interconnection of physical components and specialized services for value co-creation. Hence, it is promising to realize the positive improvement of PHC based on an SPSS approach, especially during the challenging post-COVID-19 pandemic era. We developed an intelligent platform based on service-oriented manners with practical case demonstration for interactive innovation of PHC shareholders, among which prefabricated components (PC) have been defined as the SCP in PHC, and a platform-enabled approach has also been adopted in the way of SPSS. Furthermore, distributed security technology viz. blockchain along with inclusive ICT (e.g., Internet-of-Things (IoT), Cyber-Physical System (CPS), and Building Information Modeling (BIM)) are employed jointly to spark new modes of smart construction. Meanwhile, valuable exploration and open research directions are expected to facilitate the PHC supply chain to become more resilient in sustainability.

With the adverse impacts of construction and demolition (C&D) waste on society, environment and economics, the waste management issues brought by C&D activities have received extensive attention worldwide. Advanced technologies have been increasingly adopted with the rapid development of technology to efficiently solve these issues. To handle the management problems with advanced technologies, a considerable number of publications have been published among world-famous peer-reviewed journals relate with C&D waste management during the past decades. But, there is a lack of a comprehensive examination on the research trend of advanced technologies in this discipline currently. As a result, this paper outlines the mainstream topics of research trend in field of C&D waste management through investigating publications from 2000 to 2019. A total of 52 papers were collected after the issue-by-issue filtering process. Analysis of the major reasons for applying advanced technologies in this discipline was conducted. This paper illustrates the current limitations and potential research interests and provides an overall picture of the existing applications of advanced technologies adopted in this discipline. According to the results of this study, stakeholders and researchers can obtain a deeper knowledge of the research trend of this discipline.

Prefabrication has been widely deployed as an integral part in the intelligent construction, of which prefabrication supply chain resilience (SCR) will play a significant role. However, when an emergency [e.g., the outbreak of the novel coronavirus disease (COVID-19)] occurs, prefabrication’s life-cycle management will be seriously threatened. Besides, there exists efficiency and interaction challenges such as schedule delays, invisible progress, and fragmented information transmission. This article aims at developing an intelligent platform based on inclusive technologies, incorporating blockchain, building information modeling (BIM), and Internet of Things (IoT) to facilitate the real-time management of prefabrication supply chain. Specifically, from the perspective of stakeholders, this platform not only shares real-time interactive information management and control but also provides reliable support for decision making. As far as potential security issues are concerned, a blockchain framework is proposed to reveal how it helps to guarantee the reliability and authenticity of the entire supply chain. Under this platform, a case study in Shenzhen is presented to demonstrate the feasibility of the platform. With the guarantee of interactive efficiency and data reliability, the prefabrication supply chain is considered to be more resilient to disruptions.

As the core of advanced digital management application technology, BIM is widely used in various infrastructure construction. Prefabricated assembly substation uses advanced, reliable and environmentally friendly intelligent modular units to form an intensive closed substation. It takes digitization, networking and standardization of information as its basic requirements. Compared with conventional substation, it occupies less space, has shorter construction period, lower cost, no noise and no detection. Radiation-free and maintenance-free environment-friendly intelligent substation. A real digital information model of the whole substation depth is established by combining the Internet, big data, IoT and the construction process. Decomposition is performed in accordance with construction management and control steps to achieve model construction growth, according to Gantt chart schedule. The corresponding mechanism between the 2D code scan and the model is established, and the relationship between the digital model and the real nodes in the construction process is implemented. The life cycle of power transmission and transformation projects is facilitated by establishing appropriate management and control platform and developing the functional modules of the app. The Building Information Modeling technology is used to accurately calculate project quantities, strengthen the management and control of material cost information, provide efficient engineering quantities calculation and reduce cost. Based on the prefabricated assembly substation of 110 kV Longhua Center, this paper gives the corresponding case introduction and promotion suggestions from the aspects of prefabricated component production, assembly construction, information management technology and so on, aiming at applying it to the construction management stage of the substation industrialization project.

Building energy consumption is the main contributor to the total energy consumption, which has an increasing impact on the environment. A systematic and comprehensive life cycle perspective assessment of building energy is crucial to maintaining project sustainability. Building energy analysis from life cycle perspective has been increasingly favoured by scholars. However, contents and links of many literatures have not been summarized, and there is a lack of systematic literature research. This review-based study adopted a three-step workflow consisting of bibliometric literature search, science mapping (keywords analysis), and systematic discussion to mining the recent decade’s research of life cycle energy of buildings (LCE-B). Keywords analysis revealed the emerging research topics, such as Environmental impact, BIM, nZEBs and passive houses. A follow-up systematic discussion summarised mainstream research topics (e.g. trade-off between operating energy and embodied energy), discusses existing research gaps (e.g. stakeholder factors) and identified future research directions. This study helps scholars obtain an in-depth understanding of state-of-the-art LCE-B research, providing a comprehensive knowledge framework and allowing linkages on the current research field to future research trends.

Emerging advanced technologies (EAT) have been regarded as significant technological innovation which will greatly help transform the construction industry and they have been adopted widely in the prefabricated construction. As the research on emerging advanced technologies in the management of prefabricated construction (MPC) has not been involved, various researchers require a state-of-the-art summary of EAT research and implementation in the MPC field. The purpose of this paper is to provide an objective and systematic summary of advance EAT by analyzing published EAT research in 10 leading journals during period from 2009 to 2019 in terms of the annual number of EAT papers, contributions of authors and countries, and research interest. Through a thorough review of selected papers from the state-of-the-art academic journals in the construction industry, the EAT research in the MPC field is reviewed and summarized. This study is of value in offering useful and original insights to summarize the advance status quo of EAT knowledge, helping researchers in related fields gain an in-depth understanding of underlying structure of EAT in the MPC and allow them to continue from the findings of studies.

Global governments only collect landfill taxes and fees for the disposal of most construction waste and ignore discount and economic compensation measures. Thus, stimulating construction contractors’ enthusiasm for recycling waste resources becomes difficult, and construction waste utilization remains at a comparatively low level. This study first constructs a compensation model of evolutionary game for construction waste treatment costs, wherein the government, developer, and contractor are the players. It aims to solve the corresponding game equilibrium points. Then, this work establishes a stock-flow diagram of the evolutionary game among the three players using the system dynamics principle to analyze the stability of the local equilibrium points obtained during the evolutionary game. The research conclusion can improve the theory of construction waste management in the theoretical contribution, especially in the field of economic incentive theory. On the other hand, the practical significance of this paper lies in exploring the active measures to lead the contractors and developers willing to recycle and reuse waste, and promoting the recycling rate of construction waste.

The purpose of this research was to explore the effects of various fuel temperatures on the injection velocity of swirl nozzles. A phase Doppler particle analyzer (PDPA) and particle image velocimetry (PIV) were used to measure the velocity of fuel sprayed by an injector into the normal atmosphere. The flow characteristics and velocities of the droplet were studied at low to high temperatures (−40 °C to 80 °C). The results showed that: 1) the flow number (FN) and mass flow of the swirl nozzle decreased with the increase of the fuel temperature under the same supply pressure; 2) the existence of “pressure critical point” and “temperature critical point” makes the nozzle flow pattern and spray pattern change, thereby changing the distribution of droplet velocity and particle size in space; 3) the PDPA measurement results showed that under the same supply pressure, a larger droplet velocity on the fuel mist cone and a smaller Sauter Mean Diamter (SMD) were measured at high temperature of fuel.

In view of the detection performance constraints brought by the further application of demagnation and noise reduction technology to traditional sonar and magnetic anomaly detection technology, in order to explore the possibility and detection mode of active electromagnetic (EM) detection technology applied to underwater large target detection and positioning, the active EM detection method for underwater targets based on SLF/ELF artificial EM field source is established in this paper, and the active EM detection method of underwater target is modeled and simulated by Ansys Maxwell, the magnetic anomaly field induced by underwater target is calculated and analyzed. Then, the key parameters of the underwater target active EM detection system are listed based on the simulation, and a underwater target active EM detection prototype has been developed. Finally, the simulation results and prototype parameters of the active EM detection method of underwater targets are verified by the scaled ratio experiment. The results show that the parameters of prototype system designed according to the simulation results are correct and effective, and the active EM detection technology based on SLF/ELF can be applied to the underwater large target detection.

In order to solve the problem that it is difficult to take into account the computational efficiency and accuracy of electromagnetic field froward modeling of electrical antenna under the stratified ocean, evaluate the performance of two non-uniform sparse segmentation integral calculation methods based on Gauss integrals and improve the efficiency and accuracy of data interpretation in engineering applications, firstly two non-uniform sparse segmentation calculation methods based on Gauss integral nodes (Gauss-Legendre integral nodes and Gauss-Chebyshev integral nodes) are introduced. Then, two fast numerical integration methods corresponding of the time and frequency domain of the electrical antenna electromagnetic field under stratified ocean is established. Finally, by comparing and analyzing the results of the traditional uniform dense segmentation numerical integral calculation from the two aspects of computational accuracy and efficiency, the results show that two non-uniform sparse segmentation integral methods can improve the computational efficiency under the condition that the calculation accuracy is comparable, and the non-uniform sparse integral calculation method based on the Gauss-Chebyshev integral nodes is more significant than the calculation efficiency performance of the method based on the Gauss-Legendre integral node. At the same time, the general parameter setting of the non-uniform sparse segmentation integral method is given in this paper.

Energy consumption of buildings is at the forefront of the total energy consumption list, and its environmental impact is increasing, thus making construction industry as a key player in energy. A systematic and comprehensive life cycle perspective assessment of building energy is crucial for maintaining project sustainability. Building energy analysis from life cycle perspective has been increasingly favoured by scholars. However, the links and contents of many literatures have not been summarized and lacking systematic literature research. This review-based research used a holistic analysis approach as the framework. Bibliometrics method in the first stage was used to select 255 papers published during 2009–2019 related to life cycle energy of buildings (LCE-B). Scientometric analysis in the second stage was adopted for identifying the journal sources, scholars, regions and articles that have been fruitful and influential in LCE-B research, and keywords analysis was proposed to preliminarily explore the research topics in the domain (e.g. analysis of optimisation). Results showed that BIM and multi-objective optimisation have become research hotspots recently. An in-depth qualitative discussion in the last stage was conducted to achieve three main objectives: (1) summarise mainstream research topics (e.g. calculation and parameter determination of embodied energy); (2) discuss existing research gaps (e.g. the spatial heterogeneity of embodied energy); and (3) identify future research directions. This study provides a comprehensive knowledge framework combined with philosophical theories that links current research fields with future research trends, providing researchers with multi-disciplinary guidance to gain insight into the latest research on LCE-B.

Information technologies are increasingly adopted across the world to promote the efficiency of construction and demolition (C&D) waste management and alleviate the environmental and social effects of waste disposal. In addressing management issues of C&D waste by information technologies, several studies have been published by international peer-reviewing journals related to construction management over the past decades. However, a systematic summary on the research development in information technologies used in C&D waste management discipline is lacking. Therefore, this study examines the latest research situation in this discipline by analysing published construction management research in peer-reviewing journals in the period of 2000–2019, and 57 related papers are collected by filtering. The characteristics of the collected papers are classified according to the following criteria: application scenarios in C&D waste management and different technologies. Eight categories of present advanced technologies used in C&D waste management are identified, namely, building information modelling, geographic information system, big data, radio frequency identification, image recognition technology, image analysis, global positioning system and barcode technology. A critical analysis of the identified technologies is conducted in accordance with their characteristics and applications. This study also performs the scientometric analysis of the collected papers by VOSviewer. The limitations of information technologies and the recommendations for potential future research directions are presented on the basis of the analytical review.

Motivation is crucial and imperative in positively achieving language learning goals. Learning English as a second language (ESL) is a demanding and challenging task which often makes Chinese students stressed, anxious and consequently unable to perform well in the English language classroom. Recent research into motivation in language learning has revealed that motivation has considerable benefits to facilitating the learning process as a means of improving students’ confidence and promoting class participation. A positive motivation enables language learners to become more focused and proficient in learning the use of another language. This paper critically examines the significance of motivation in English language learning in the Chinese context, and argues that increasing motivation can provide learners with significant advantages in improving confidence and enhancing classroom involvement in the language classroom. It is suggested that motivation, through development of a combination of intrinsic and extrinsic factors, can be harnessed for positive student outcomes.

Pipelines are important in transporting oil and gas in offshore engineering. During the service condition, this external water pressure could be compensated by the internal pressure induced by the gas or oil within the pipeline. However, during the pipe-laying or maintenance, the internal pressure in the pipeline will disappear. The huge external water pressure will cause local buckling or crushing first at defect or damage part of pipelines. Experimental research is one of the important means to investigate the pipeline buckling phenomena. Most of the existing hyperbaric chambers are in small scale, which could not perform experiments with the actual pipe used in the offshore engineering. Due to this reason, the most of the published experimental results obtained from these hyperbaric chambers are in small scale where the cross section size was reduced with same diameter-thickness ratio. In order to avoid the scale effects on the experimental phenomena and results, a full-scale hyperbaric device was designed by the Institute of Offshore and Naval Engineering of Tianjin University, China. Twelve series of full-scale buckling tests were conducted in this paper, with the intention of investigating the influence of diameter-thickness ratio and initial imperfection on the buckling pressure. Furthermore, the numerical simulation using ABAQUS was performed to compare the experimental results. The comparison shows a good agreement, where the average difference is about 6% to 7%.

Synthetic biology involves reprogramming and engineering of regulatory genes in innovative ways for the implementation of novel tasks. Transcriptional gene regulation systems induced by small molecules in prokaryotes provide a rich source for logic gates. Cross-regulation, whereby a promoter is activated by different molecules or different promoters are activated by one molecule, can be used to design an OR-gate and achieve cross-talk between gene networks in cells. Acinetobacter baylyi ADP1 is naturally transformable, readily editing its chromosomal DNA, which makes it a convenient chassis for synthetic biology. The catabolic genes for salicylate, benzoate, and catechol metabolism are located within a supraoperonic cluster (-sal-are-ben-cat-) in the chromosome of A. baylyi ADP1, which are separately regulated by LysR-type transcriptional regulators (LTTRs). ADP1-based biosensors were constructed in which salA, benA, and catB were fused with a reporter gene cassette luxCDABE under the separate control of SalR, BenM, and CatM regulators. Salicylate, benzoate, catechol, and associated metabolites were found to mediate cross-regulation among sal, ben, and cat operons. A new mathematical model was developed by considering regulator-inducer binding and promoter activation as two separate steps. This model fits the experimental data well and is shown to predict cross-regulation performance.

A rapid, sensitive, and specific method using liquid chromatography tandem mass spectrometry (LC/MS/MS) has been developed for simultaneous determination of testosterone (T), dihydrotestosterone (DHT), estradiol (E2), and 5alpha-androstan-3alpha, -17beta-diol (3alpha-Diol) within human testicular fluid. Sample pretreatment involved a one-step extraction with diethyl ether. The analytes were separated on a Waters X-Terra C18 (150 mm x 2.1 mm i.d., 3.5 microm) analytical column with acetonitrile/water mobile phase (70:30, v/v) containing 0.1% formic acid using isocratic flow at 0.15 ml/min for 8 min. The column effluent was monitored by tandem mass spectrometry with electrospray positive ionization. Linear calibration curves were generated over the range of 0.1-50 ng/ml for T, 0.02-1 ng/ml for DHT, 0.05-2 ng/ml for E2, and 0.2-10 ng/ml for 3alpha-Diol, with values for the coefficient of determination of0.99. The overall extraction efficiency was greater than 86% for T, 75% for DHT, 66% for E2, and 60% for 3alpha-Diol. The values for within-day and between-day precision and accuracy were15%. We measured each of the four steroids in testicular sample volumes of only 20 microl, obtained by percutaneous testicular aspiration. The mean intratesticular testosterone concentration found by LC/MS/MS, 572 +/- 102 ng/ml, was similar to that previously obtained by radioimmunoassay (RIA). The mean intratesticular estradiol concentration was 15.7 +/- 2.3 ng/ml, which also correlated well with RIA measurement. Both DHT and 3alpha-Diol were below the limits of detection by RIA, but could be measured accurately by LC/MS/MS. In conclusion, LC/MS/MS represents a sensitive and accurate means by which to measure four separate steroids within small volume samples of testicular fluid.