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A carbon emission factor (CEF) database is required for the basis of carbon emission calculation in construction projects. However, the default values for existing CEF databases cannot cover the complex resources involved in a construction project. Therefore, this paper proposes a three-step method to guide the establishment of an extensible CEF database for the construction industry, including (1) data collection and parser, (2) data extension, and (3) data encoding and storage. The data extension mechanisms provide the supply chain perspective considering temporal issues and the accounting perspective to streamline the process. Aiming to address the lack of a comprehensive CEF database for the construction industry in China, this paper uses this method to establish a carbon emission factor database for the Chinese construction industry (CEFD for CCI). This database is open and free with 646 CEFs, including five parts: energy, human, material, machinery, and greenspace. This paper provides a way for developing and less developed countries to establish an expandable CEF database, which benefits the parser, extension, encoding, and storage of new resources, as well as computer access.

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In the realm of civil engineering, ultra-high-performance concrete-filled steel tube composite columns (UCFSTCs) constitute a new type of building material and structure, exhibiting high compressive strength and commendable durability. Given their promising characteristics, the prospects of their application are highly promising and are worthy of further exploration. However, current research has primarily focused on scaled-down specimens, thereby limiting a broader understanding of UCFSTCs' full-scale mechanical properties in real-world scenarios. This study aimed to investigate the mechanical properties of full-scale UHPC-filled steel tube composite columns (FUCFSTCs) in practical engineering applications. With the steel tube strength, steel tube thickness, concrete strength, aspect ratio, and steel tube diameter used as design parameters and the finite element software ABAQUS as the analytical tool, a total of 21 FUCFSTCs were designed and analyzed. Through a comparison with experimental curves, the rationality of both the material constitutive model and finite element model was verified, and the maximum error was 6.54%. Furthermore, this study analyzed the influence of different design parameters on FUCFSTCs' ultimate bearing capacity, ductility coefficient, and the stress-strain relationship of their concrete. The ductility coefficient remained around 1.3, and the cross-sectional size had the greatest impact on the bearing capacity of the composite column, with a maximum increase of 145.90%. Additionally, this paper provides an in-depth analysis of FUCFSTCs' mechanical behavior, failure mode, and stress process under an axial load. In conclusion, this research proposes an axial compression limit bearing capacity formula for FUCFSTCs via statistical regression, with a maximum error of 3.04%, meeting engineering accuracy requirements. Consequently, this study lays a strong foundation for the future application of FUCFSTCs in practical engineering.

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Railway construction contributes to socio-economic development but causes the occupation and destruction of land resources. How to effectively restore the temporary land and achieve efficient and rational reuse therefore becomes particularly important. The beam fabrication and storage yard (BFSY), as a large temporary facility during railway construction, occupies a large area of land. However, BFSYs damage the land in the way of pressing and may harden the ground to a high degree due to the use of high-density pile foundations, adversely affecting the soil properties. Therefore, this research aims to develop a model for evaluating the land reclamation suitability (LRS) of BFSY. The LRS evaluation indicator system of BFSY was firstly constructed based on the literature review and expert interviews. Then, an indicator-based model for assessing the LRS of BFSY was developed by integrating the analytic hierarchy process (AHP) model and the matter-element analysis (MEA) model. A case project in China was chosen to demonstrate and validate the developed model, and results show that the proposed model can rationally evaluate the LRS of BFSY in railway construction. The findings of this research enrich the knowledge system of sustainable railway construction and guide construction managers to conduct practical suitability assessments of land reclamation.

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There is a growing consensus that recycled water, as an alternative and renewable water source, can serve as a vital water supply to alleviate water scarcity problem and in support of water resilience. Accordingly, recycled water infrastructure investment has seen a significant growth in recent years in many regions of the world. However, previous studies found the perceptions of public, the main end user, toward using recycled water for potable or non-potable purposes remain negatively stereotyped. The negative stereotypes led to public rejections to the construction and operation of recycled water infrastructure. Traditionally, public perceptions of recycled water uses are captured through self-reporting interview or survey techniques. To gain a more accurate measurement of the implicit public stereotypes toward recycled water uses, this study employed an event-related potential (ERPs) technique to collect neurophysiological responses with participants and presented a few research findings. Firstly, the negative stereotypes of recycled water still exist. Secondly, the degree of human contact impacts the negative stereotypes of participants toward recycled water uses more significantly on the supply side (referring to the whole supply chain of recycled water) rather than on the demand side (referring to the potential consumers of recycled water) Third, knowledge level significantly impacts the negative stereotypes of participants toward recycled water uses that have close human contact, at both supply and demand sides, and shows a more significant impact on the supply side. The findings of study contributed to the literature through creatively dividing the negative stereotypes of recycled water into the "supply-side" and the "demand-side" ones, and meanwhile have managerial implication for policymaking and scheme implementation in the area.

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Safety is the most important concern in the construction industry, and construction workers' attention allocation is closely associated with their hazard recognition and safety behaviors. The recent emergence of eye-tracking techniques allows researchers in construction safety to further investigate construction workers' visual attention allocation during hazard recognition. The existing eye-tracking studies in construction safety need to be comprehensively understood, to provide practical suggestions for future research and on-site safety management. This study aims to summarize previous studies on the application of eye-tracking techniques to the construction safety context through a systematic literature review. The literature search and study selection process included 22 eligible studies. Content analysis was then carried out from participant selection, device selection, task design, area of interest determination, feature extraction, data analysis, and main findings. Major limitations of the existing studies are identified, and recommendations for future research in theoretical development, experiment improvement, and data analysis method advancement are proposed to address these limitations. Even though the application of eye-tracking techniques in construction safety research is still in its early stage, it is worth future continuous attention because relevant discoveries would be of great significance to hazard control and safety management in the construction industry.

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The ideas of face consciousness, group conformity, extended family concept, and crisis consciousness in Confucian culture have a subtle and far-reaching impact on housing consumption decision among the Chinese public, forming a housing consumption model of "preferring to own a house rather than rent one." The poor interaction between the housing rental market and the sales market caused by the shortage of rental demand and irrational purchasing behaviors has led to soaring house prices and imbalance between supply and demand that prevail in major cities in China. To gain a deeper understanding of public cognitive attitude toward decisions on owning and renting a house, this study divided the subjects into high and low impact groups based on the overall Confucian culture and four subdimensions. It attempts to take a cognitive neuroscience approach for assessing public stereotypes of housing consumption decision with different types based on the analysis of event-related potentials (ERPs). The results are as follows. First, overall, there is an obvious implicit stereotype of renting a house and explicit stereotype of owning a house among the public. Second, ERPs data show that descriptions of renting a house with positive adjectives could evoke more significant N400 responses. In other words, in the heuristic system, the public perceive that renting a house is restrictive, stressful, unhappy, and crisis. Data from subjective reports show that, after processing information in the analytic system, the public tend to think that owning a house is self-contained, restful, warm, and comfortable. Third, a more negative stereotype of renting a house exists in the high Confucian culture influence group (HIC) Group than in the low Confucian culture influence group (LIC) Group, and is more inclined to own a home. Fourth, under the Confucian culture sub-dimension, there are differences in housing consumption stereotypes between high and low groups in terms of extended family concept, group conformity, and crisis consciousness. Fifth, the moderating effect analysis found that perceived usefulness, trust in the rental market, and policy perception can be important factors in guiding public housing consumption stereotypes.

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As an indispensable part of cities, wastewater treatment plants play an important role in environmental protection and urbanization. However, the promotion of wastewater treatment plants has been consistently hindered by residents' negative stereotypes and rejections, which is called "Not-In-My-Back-Yard" (NIMBY) effect. This study collected the first-hand data with the residents residing within 3 kilometers of 9 wastewater treatment plants in Xi'an, China through a survey. Keyword co-occurrence network analysis was conducted and the results illustrate that residents have stereotypes toward wastewater treatment plants. There are two types of residents' stereotypes toward wastewater treatment plants: positive and negative. The positive stereotypes of wastewater treatment plants in turn can be subdivided into the three categories of treatment technologies, treatment results, and social impacts. But the negative stereotypes didn't demonstrate meaningful categories. We also tried to identify the influencing factors that cause residents' stereotypes. The distance from residents' residence to the wastewater treatment plants has impacts on the stereotypes of residents' who reside within 1000 meters of the wastewater treatment plant: the farther from the wastewater treatment plants their residence is, the more positive their stereotypes are. We also found that the more educated the participants are, the more positive stereotypes of wastewater treatment plants they have. Moreover, residents' stereotypes toward wastewater treatment plants are more influenced by formal education. Non-formal education and informal learning probably have less influence on the promotion of wastewater treatment plants. Therefore, we propose to incorporate environmental education for sustainable development into formal education to increase residents' acceptance of wastewater treatment plants.

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This paper develops a simulation model for analyzing how government incentives and punishments improve contractors' participation in resource utilization of construction and demolition waste (RUCDW) based on system dynamics theory. The construction industry's long-term objective is to become more sustainable and resource-effective, and as part of this objective, generated construction and demolition waste should be recycled and resource utilized. However, most contractors have little willingness to engage in RUCDW because it increases their costs. The government thus plays a vital role in improving their participation in RUCDW through a range of educational tools such as advertisements, professional training, incentives, and punishments. Among these approaches, incentives and punishments are considered the most effective because they directly change project costs. We use the Vensim software package for numerical simulation and data collected from Suzhou, China are used to demonstrate and validate the developed model. Simulation results show that the government can improve contractors' participation in RUCDW through three kinds of incentives and punishments: (1) subsidizing RUCDW; (2) increasing landfill fees; and 3) issuing fines for illegal dumping. Comprehensive application of multiple policies has a stronger effect than single policies. The established model is therefore a valuable tool for assessing the dynamic effects of government incentives and punishments on RUCDW ahead of implementation, which can provide guidance for policymakers.

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Gastric cancer (GC) is a very common malignancy with a poor prognosis, and its occurrence and development are closely related to epigenetic modifications. Methylation of DNA before or during gastric cancer is an interesting research topic. This article reviews the studies on DNA methylation related to the cause, diagnosis, treatment, and prognosis of gastric cancer and aims to find cancer biomarkers to solve major human health problems.

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Nonalcoholic fatty liver disease (NAFLD) is reported to affect 20-30% of adults and is accompanied by various metabolic comorbidities, where the economic and clinical burden of NAFLD is attributed to the progression of liver disease as well as the presence of extrahepatic diseases. Chronic kidney disease (CKD), which has a high incidence rate, high morbidity and mortality rates, and high medical costs, has been linked to NAFLD. CKD is associated with some metabolism-related risk factors that overlap with metabolic comorbidities of NAFLD. Therefore, to investigate the potential factors that influence CKD occurrence, the association between NAFLD and CKD should be clarified. Some studies have confirmed that NAFLD influences the occurrence and severity of CKD, whereas some studies have indicated that there is no correlation. In this review, the results of a few studies have been discussed, the potential risk factors for CKD in NAFLD are explored, and the respective biological mechanisms are elaborated to help clinicians identify CKD in patients much earlier than it is diagnosed now and thus help in reducing the incidence of liver and kidney transplants.

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Prefabrication is a promising method for minimizing construction waste since it is conducted in a controlled environment. This paper develops a simulation model for quantitatively evaluating the potential of prefabrication on construction waste reduction by considering interaction behaviors among factors influencing the application of prefabrication and construction waste reduction during the design stage. The theory of planned behavior is applied to determine the system boundary, and a system dynamic model is applied for establishing the simulation model. A case project in Anhui, China, is selected for demonstrating the established model. Results show that the (1) Application of prefabrication method contributes to construction waste reduction by reducing material wastes and reworking due to design changes. (2) Impacts of prefabrication method on concrete waste reduction is the most significant. (3) Increasing investment on designers' professional training and strengthening policies is two efficient strategies to make full use of the potential of the prefabrication method on construction waste reduction during the design stage. The developed model can offer designers as well as policymakers with references for applying prefabrication method for construction waste reduction by comparing outcomes under various scenarios with different strategies and policies ahead of implementation.

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BACKGROUND: Hepatocellular carcinoma (HCC) is one of the main reasons for malignancy-related death. Portal vein tumor thrombosis (PVTT) is the most common form of macrovascular invasion related to HCC occurring in 10%-60% of patients. HCC with PVTT is usually characterized by worsening liver function, vulnerability to blood metastasis, higher incidence of complications associated with portal hypertension, and intolerance to treatment when compared with that without PVTT. If only treated with supportive care, the median survival of HCC with PVTT is about 2.7 months. In the past, sorafenib was the only recommended therapy by guidelines with limited effectiveness. This narrative review aimed to describe the current management options for HCC with PVTT. DATA SOURCES: We have reviewed literature from PubMed on the treatment of HCC with PVTT and compiled evidence-based facts on effective therapies available for different types of PVTT. RESULTS: Sorafenib monotherapy is not much effective, but combining it with other methods can improve survival. Each type of PVTT can benefit from the combination of transarterial chemoembolization and sorafenib than sorafenib monotherapy. The tumor downstaging can be realized possibly after transarterial chemoembolization, but tumor invasion into the main trunk of the portal vein greatly impairs efficacy. Although surgery is a curative approach, it is often not recommended for Vp4 PVTT. Some new methods can broaden the indication, but further explorations are needed. Radiotherapy can decrease the possibility of Vp3 progression to Vp4, but building a forecast model of best radiation dose and response is necessary. Systemic chemotherapy, hepatic arterial infusion chemotherapy, radiofrequency ablation, portal stenting, and traditional Chinese medicine are also beneficial in Vp3-4 PVTT. The accurate diagnosis of PVTT can be made by radiomics, and prognostic classification models can be used to design personalized treatments. The application of new treatment methods such as the atezolizumab plus bevacizumab scheme may increase survival. CONCLUSIONS: HCC with PVTT is still a thorny problem, and effective therapeutics need to be explored.

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BACKGROUND: The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) in coronavirus disease-2019 (COVID-19) patients and whether it affects the outcomes of COVID-19 requires investigation. GOALS: The aim was to determine the prevalence of MAFLD among COVID-19 patients and its influence on the outcomes of COVID-19 by meta-analysis. METHODS: Our study protocol has been registered on PROSPERO (CRD42021242243). The studies published on PubMed, Embase, Cochrane Library, and Web of Science before March 11, 2021 were screened. The Newcastle-Ottawa scale (NOS) and Agency for Healthcare Research and Quality scale were used to assess the quality of the studies. Pooled analysis was conducted using the software RevMan version 5.3 and Stata version 15.0 SE. The stability of the results was assessed by sensitivity analysis. Publication bias was evaluated using funnel plots, Egger test, and trim-and-fill analysis. RESULTS: Seven studies covering 2141 COVID-19 patients were included. It was confirmed that MAFLD increased the risk of severe COVID-19 (odds ratios: 1.80, 95% confidence interval: 1.53-2.13, P<0.00001). No association was found between the presence of MAFLD and the occurrence of COVID-19 death. The pooled prevalence of MAFLD among COVID-19 patients was 36% (95% confidence interval: 0.23-0.49, P<0.00001). Sensitivity analysis confirmed that the initial results were stable. CONCLUSIONS: MAFLD can increase the incidence of severe COVID-19, but the correlation between MAFLD and COVID-19 death has not been confirmed. Further investigation is needed to explore the possible mechanism of this association. Since MAFLD is common among patients infected with SARS-CoV-2, more care should be given to COVID-19 patients with underlying MAFLD.

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BACKGROUND AND AIMS: Highly accurate noninvasive methods for predicting gastroesophageal varices needing treatment (VNT) are desired. Radiomics is a newly emerging technology of image analysis. This study aims to develop and validate a novel noninvasive method based on radiomics for predicting VNT in cirrhosis. METHODS: In this retrospective-prospective study, a total of 245 cirrhotic patients were divided as the training set, internal validation set and external validation set. Radiomics features were extracted from portal-phase computed tomography (CT) images of each patient. A radiomics signature (Rad score) was constructed with the least absolute shrinkage and selection operator algorithm and tenfold cross-validation in the training set. Combined with independent risk factors, a radiomics nomogram was built with a multivariate logistic regression model. RESULTS: The Rad score, consisting of 14 features from the gastroesophageal region and 5 from the splenic hilum region, was effective for VNT classification. The diagnostic performance was further improved by combining the Rad score with platelet counts, achieving an AUC of 0.987 (95% CI 0.969-1.00), 0.973 (95% CI 0.939-1.00) and 0.947 (95% CI 0.876-1.00) in the training set, internal validation set and external validation set, respectively. In efficacy and safety assessment, the radiomics nomogram could spare more than 40% of endoscopic examinations with a low risk of missing VNT (< 5%), and no more than 8.3% of unnecessary endoscopic examinations still be performed. CONCLUSIONS: In this study, we developed and validated a novel, diagnostic radiomics-based nomogram which is a reliable and noninvasive method to predict VNT in cirrhotic patients. CLINICAL TRIALS REGISTRATION: NCT04210297.

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BACKGROUND: Global research on endoscopic therapies in combination with partial splenic embolization (PSE) for variceal hemorrhage (VH) is limited. Therefore, we aimed to evaluate the efficacy and safety of endoscopy plus PSE (EP) treatment in comparison to endoscopic (E) treatment for the secondary prophylaxis of VH in cirrhosis patients with hypersplenism. METHODS: Cirrhosis patients with hypersplenism (platelet count < 100, 000/µL) and those who had recovered from an episode of VH were enrolled in a multicenter randomized controlled trial. The participants were randomly assigned into EP and E groups in a 1:1 ratio. The primary endpoint was variceal rebleeding, and the secondary endpoints were severe variceal recurrence and mortality during the 2-year follow-up. Hematological indices, serum biochemical parameters, and the Child-Pugh score were measured at each time point. RESULTS: From June 2016 to December 2019, 108 patients were enrolled in the study, among which 102 patients completed the protocol (51 in EP and 51 in E group). The rebleeding rate of the varices was significantly reduced in the EP group compared to that in the E group during the 2 years (16% vs. 31%, p < 0.001). The EP group showed a significantly lower variceal recurrence rate than the E group (22% vs. 67%, p < 0.001). The COX proportional hazard models revealed that grouping was an independent predictor for variceal rebleeding (H = 0.122, 95% CI 0.055-0.270, p < 0.001) and variceal recurrence (hazard ratio, H = 0.160, 95% CI 0.077-0.332, p < 0.001). The peripheral blood cell count, Child-Pugh class/score, albumin concentration, and coagulation function in the EP group improved significantly compared to the values observed in the E group at any time point (p < 0.05). CONCLUSIONS: The EP treatment was more effective in preventing variceal rebleeding and variceal recurrence than the conventional E treatment during the secondary prophylaxis of VH in cirrhosis patients with hypersplenism. Furthermore, the EP treatment could significantly increase the peripheral blood cell count and albumin concentration and also improved the coagulation function and the Child-Pugh score. CLINICAL TRIALS REGISTRATION: Trial registration number ClincialTrials.gov: NCT02778425. The URL of the clinical trial: https://clinicaltrials.gov/.

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This study aimed to research the whole stress-strain curves of coral Fly Ash-Slag Alkali-Activated Concrete (CAAC) in different strength grades. Fly ash-slag alkali-activated concrete was used as cementing materials to produce coral aggregate concrete. A monotonic loading test was conducted on the prismatic specimens to obtain elastic modulus (Ec), Poisson's ratio (µ) and the constitutive relationship of CAAC under uniaxial compression. When the strain of CAAC reached the maximum value, the specimen was split and damaged rapidly. As the strength grade increased, the ratio of residual stress (σri) to peak stress (σ0i) decreased in the range of 0.17-0.28. The Ec of CAAC increased gradually, and µ increased to the peak value and then decreased. According to the test results, the constitutive equation of CAAC can be expressed by piecewise expression, which can better reflect all the experimental characteristics. It was also found that CAAC has many similar characteristics with coral concrete and lightweight aggregate concrete. To improve the strength and toughness of CAAC, some fibers, such as organic fiber, can be added to expand the application of CAAC in engineering projects.

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This paper investigated the performance of actively confined geopolymer concrete (GPC) through experiments. The mechanical properties of GPC under triaxial stress states were analyzed and discussed from the prospects of failure modes, axial peak stress and strain, monotonic and cyclic constitutive relationships. The experimental results demonstrated that the loading modes (monotonic loading and cyclic loading) had little effect on the failure mode and axial peak stress and strain. The improvement of the strength and ductility of GPC with the increase in confinement level was consistent with that of the conventional cement concrete while the strain enhancement of confined GPC was lower than that of confined conventional cement concrete at the same confinement level. The curves of the monotonic stress-strain and the envelop of cyclic compression were predicted through Mander's model with good accuracy. The unloading/reloading models proposed by Lokuge were modified and the predicted cyclic hysteresis curves for actively confined GPC were in good agreement with the cyclic compression results. Findings from this study provide references for the application of geopolymer concrete.

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INTRODUCTION: Anticoagulation therapy in portal vein thrombosis (PVT) in patients with cirrhosis is still a matter of debate. Therefore, the aim of this work was to evaluate the efficacy and safety of nadroparin calcium-warfarin sequential (NWS) anticoagulation therapy in cirrhotic patients and to find an optimal anticoagulation strategy. METHODS: Consecutive cirrhotic patients with PVT who have not received anticoagulation therapy were randomly divided into the NWS therapy group (1-month nadroparin calcium by subcutaneous injection followed by 5-month warfarin by oral administration) and control group (no anticoagulation therapy). Overall recanalization rate of PVT and risks of bleeding were evaluated at the sixth month. RESULTS: Among 64 patients, complete or partial recanalization of PVT was observed in 20/32 NSW therapy group patients vs 11/32 control group patients (62.5% vs 34.4%, P = 0.024), with no statistically significant difference in bleeding rate. Child-Pugh score (P = 0.023), D-dimer < 2.00 µg/mL (P = 0.020), and NWS anticoagulation therapy (P = 0.004) were predictors associated with the recanalization. NWS anticoagulation therapy (P = 0.008) was an independent predicting factor of recanalization. In the NWS therapy group, the Child-Pugh score (P = 0.007) and albumin level (P = 0.004) were improved in the sixth month. DISCUSSION: NWS anticoagulation therapy was effective and safe in PVT patients with cirrhosis and could increase the level of albumin. NWS therapy is safe and easily accepted.

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Prefabrication has gained its popularity in countries including China due to its various advantages such as quality control, waste reduction, onsite and offsite parallel coordination, and so on. It has also been recognized as a key strategy to reduce construction-induced carbon emissions. However, there is limited research to examine carbon emission reduction in prefabrication by using the advanced technological artefacts, e.g., building information modeling (BIM), emerging from the technology sphere. As a digital representation of a facility, BIM provides a cyber platform based on which many assessment and simulation works can be performed without having to construct the physical facility. This paper aims to develop a BIM-based approach to measuring carbon emission reduction during the materialization stage of a prefabricated building project. Findings from the study indicate that BIM is an efficient and effective method for measuring carbon emissions from the construction of new buildings and that prefabrication reduces carbon emissions when compared with conventional construction methods. The research contributes to the body of knowledge relating to the reduction of carbon emissions through prefabrication. This is pertinent to contractors, homebuyers and governments who are constantly seeking ways to achieve a circular economy.