Endo-Epicardial Homogenization of the Scar Versus Limited Substrate Ablation for the Treatment of Electrical Storms in Patients With Ischemic Cardiomyopathy

ObjectivesThis study investigated the impact on recurrences of 2 different substrate approaches for the treatment of these arrhythmias.BackgroundCatheter ablation of electrical storms (ES) for ventricular arrhythmias (VAs) has shown moderate long-term efficacy in patients with ischemic cardiomyopathy.MethodsNinety-two consecutive patients (81% male, age 62 ± 13 years) with ischemic cardiomyopathy and ES underwent catheter ablation. Patients were treated either by confining the radiofrequency lesions to the endocardial surface with limited substrate ablation (Group 1, n = 49) or underwent endocardial and epicardial ablation of abnormal potentials within the scar (homogenization of the scar, Group 2, n = 43). Epicardial access was obtained in all Group 2 patients, whereas epicardial ablation was performed in 33% (14) of these patients.ResultsMean ejection fraction was 27 ± 5. During a mean follow-up of 25 ± 10 months, the VAs recurrence rate of any ventricular tachycardia (VTs) was 47% (23 of 49 patients) in Group 1 and 19% (8 of 43 patients) in Group 2 (log-rank p = 0.006). One patient in Group 1 and 1 patient in Group 2 died at follow-up for noncardiac reasons.ConclusionsOur study demonstrates that ablation using endo-epicardial homogenization of the scar significantly increases freedom from VAs in ischemic cardiomyopathy patients

Examining the impact of corporate commitment to sustainability

textThis dissertation presents the culmination of a research study, started at the University of Texas at Austin in August 2003. The main objective of the study was to establish a research mechanism to investigate the impact of corporate commitment to all three pillars of sustainability on capital project planning and capital project performance. The research hypothesis was that a higher balanced commitment to the three pillars of sustainability leads to better capital project planning and ultimately to better cost and schedule performance in large industrial and building projects, by mitigating the risks in project execution. To achieve the objectives of this study, sustainability indicators were condensed into two empirical indices. The first index measured Corporate Commitment to the three pillars of sustainability. It is referred to as the Corporate Sustainability Commitment Index (CSCI). The second index measured the degree of integration of sustainable practices in capital project planning. It is referred to as the Sustainability Component of Project Planning Index (SCPPI). The research study then focused on the two most important project performance measures, cost and schedule predictability. Project success is typically referred to as meeting business objectives, on time, and within budget. Therefore, 38 Fortune 100 multinationals were contacted and data on CSCI, SCPPI and project performance was collected from 20 of these organizations. Seventeen of the 20 organizations were owners and three were top contractors. Owner data was focused on and analyzed to examine the nature of the relationship between sustainable practices and project performance, while contractor data added perspective and helped establish the nucleus for further research comparing the sustainability practices of both owner and contractor companies. The study concludes that the survey instrument and research premise are useful foundations for further examination of the relationship between owner commitment to sustainability and capital project performance. The data collection and analysis, albeit very statistically constrained by the sample size, lay the groundwork for further research. More data collections should lead to more statistically significant relationships and conclusive trends. Finally, this dissertation provides several recommendations to aid in the implementation of the study findings and the learning experience from industry input.Civil, Architectural, and Environmental Engineerin

Critical reflections on strategies for mitigating and adapting to urban heat islands

ABSTRACTCities are described as urban heat islands (UHI) due to the intensity of the heat generated by urban activities. Buildings, for example, absorb and emit heat, which contributes to urban heat. Cities contribute to global warming, which, over time, influences climate change. Cities contend with these challenges concurrently through mitigation and adaptation strategies. Through their unintended conflicts and trade-offs, the strategies may impact each other adversely. What are typologies of these trade-offs and conflicts, and how do they influence the effectiveness of UHI management by governments? To answer this research question, this paper used the desktop, case-study and evidence-based research techniques. The paper found and discussed specific conflicts and trade-offs between UHI mitigation and adaptation strategies, as well as effective integration, innovation and evaluation management mechanisms. The findings should provide actionable insights for urban policymakers and planners, on UHI management and long-term climate resilience in cities

Construction Cash Flow Risk Index

As investment increases in capital projects, financial risks increase, and cash flow prediction and control become more paramount. Higher risks could hinder project performance and increase the chances of failure in multiple aspects of a project. While there are models that aim to assess and forecast risks in the construction industry, none present a technique to include the impact of risks on a project’s cash flow. Therefore, cash flow forecasts tend to exceed the actual cash flow of a project due to inaccurate risk assessment. Thus, this paper presents the Cash Flow Risk Index (CFRI) development process quantifying the impact of risks on a project’s cash flow from an owner’s perspective. To that end, the study explored the literature to identify the risk factors that might impact a construction projects’ cash flow and uncovered 44 factors. The study also validated and consolidated these factors to build a CFRI via a Delphi exercise, which reduced the factors from 44 to 36. In further iterations, the 36 factors were also shared with 32 construction industry professionals to rate their relative importance on a five-point Likert scale, from which relative importance index and weights were obtained. As a result, the CFRI was developed to measure the impact of different risk factors on a typical construction project’s cash flow

Critical Success Factors for Building Information Modeling Implementation as a Sustainable Construction Practice in the UAE

The building sector is widely acknowledged as a driving force behind national prosperity. However, there are considerable challenges to the construction industry’s transition to sustainable practices, including regarding building information modelling (BIM) technologies. The United Arab Emirates has made significant progress in the Middle East in adopting BIM technologies. Green building approaches have been advanced through their incorporation into environmentally conscious building practices, with a large body of literature responding to this issue. Several projects in the United Arab Emirates have, however, made use of the complementary nature of BIM and UAE sustainable policies. However, not everybody has employed the full potential of BIM implementation in sustainable construction. This paper aims to identify and prioritize the critical success factors (CSFs) for effective BIM implementation as a sustainable construction practice in the UAE and examine their ranking and relationships. A list of critical success factors was gathered from a review of previous literature to identify the essential factors for successful implementation. A standardized questionnaire was distributed to consulting organizations and engineering enterprises to verify the existence of these CSFs and measure their importance in the context of the UAE’s construction industry. The survey data was analyzed using the analytic hierarchy process (AHP) technique to elaborate and validate the results, which was specifically applicable to the needs of this study. The results from the AHP analysis show that the social aspects were ranked as the highest critical success factor compared to the other criteria, namely economic, environmental, and information technology. Within this criterion, it was found that effective communication among stakeholders is the most important element, as subject matter experts feel that it is imperative to have buy-in from all or most of the construction project stakeholders to achieve the strategic goal of implementing BIM. Equally anticipated are both an effective corporate framework to back up the BIM system and government funding to build the BIM system

Assessment of the Perception of Sustainability for Occupants of Residential Buildings: A Case Study in the UAE

The residential sector is multi-faceted by nature. Although evidence shows that the UAE is among the countries in the world that take sustainability seriously, there is a lack of information about the perception of sustainability by occupants in the residential sector in the UAE. The aim of this paper is to assess the perception of sustainability of the residential sector in the UAE, which is achieved by following a methodological framework using the relevant literature review and experts’ knowledge. An online survey was distributed to the targeted population, followed by a statistical analysis to fulfill the aim of the paper. Results confirm the correlation between social, economic, and environmental aspects of sustainability. Additionally, structural equation modeling reveals that the perception of sustainability is significantly influenced by economic and environmental aspects in the residential sector in the UAE. Comparative analysis shows a statistical difference in the perception of sustainability among gender, educational level, employment status, and monthly income. Finally, a predictive classification model is built to classify the perception of occupants based on their attributes using decision tree algorithms. The outcomes of this study would be beneficial to policy and decision makers, developers, contractors, designers, and facility management entities to enhance overall sustainability in the residential sector

Data mining for sustainability analysis: an education approach

Our planet’s population is increasing at a rapid pace and with it the demand for food and resources. Environmental Sustainability (ES), a part of Sustainable Development (SD) concepts and techniques, is key in mitigating the effects of resource overuse. Several indicators have been identified and used to develop ES measures such as an environmental performance index and an environmental vulnerability index. These indices are used to evaluate countries and provide support for decision-making regarding national mitigation strategies and climate risks. This paper describes an educational approach to raise ES awareness and improve SD analytical skills among doctoral level students in Engineering Systems Management. The data used in this paper is obtained from existing ES indices and available data. The students use data mining and analytics techniques to evaluate the data, find relationships, and draw conclusions. These techniques and conclusions are then shared in class presentations and conference publications. Data mining converts raw data into useful information that can be understood by different audiences. It can be used to persuade policymakers about the importance of sustainable strategies for a country, a society, or certain groups or individuals’ welfare by highlighting meaningful patterns and trends in ES. The paper also aims to investigate possible correlations among environmental indices and their underlying indicators

Analysis of Electricity and Water Consumption in Existing Mosque Buildings in the UAE

According to the World Economic Forum, the building sector is responsible for 40% of global energy consumption and 33% of greenhouse gas (GHG) emissions, and this is expected to increase due to population growth and the subsequent impact on the environment, economy and health. To tackle the problem, countries have set new construction codes, policies and regulations for the construction of new buildings in an effort to make them greener. However, there is a need to enhance the status of the existing buildings, especially mosques, as they are the main contributors to energy usage and water consumption in the United Arab Emirates (UAE). Therefore, this research seeks to fill this gap, aiming to evaluate the energy usage and water consumption practices employed in the existing mosque buildings within the UAE and to provide recommendations for improving the sustainability of mosques, with a focus on the environmental and economic pillars. The methodology relies mainly on data collected from 146 existing mosque buildings that have undergone energy saving audits across the UAE. Descriptive statistical analysis is performed to analyze the data from the period of 2018–2019 in order to determine the most significant factors related to energy inefficiency in existing mosque buildings in the UAE and to determine the most cost-effective and energy-saving corrective measures for energy and water conservation. The findings further enhance the standard of experience for mosque visitors (social aspect); reduce energy bill expenses, providing an acceptable return on investment from the proposed energy conservation measures for stakeholders (economic); and reduce the overall energy consumption, which can reduce the total CO2 emissions from mosque buildings (environmental)

Commitment Indicators for Tracking Sustainable Design Decisions in Construction Projects

The construction industry is considered one of the largest contributors to climate change through its consumption of natural resources and generation of greenhouse gases. Much of this can be attributed to inadequate decision making and follow-up within construction companies. To mitigate this problem, considerable research on Sustainable Development (SD) reports on decision support systems have been developed in order to make sound decisions with respect to the environment. Nonetheless, and despite the availability of such tools, these systems fail to track the commitment to SD decisions and goals during the different phases of construction projects in general and the design phase in particular. As such, this study identified three standard SD indicators: waste reduction, energy consumption, and carbon emissions as the main contributors, and developed the framework to track the project stakeholders’ commitment to the relevant SD indicators during the project design phase. The developed framework was validated via an expert panel and used to create a Sustainable Development Commitment Tracking Tool (SDCTT-D). The SDCTT-D tool was also applied in an infrastructure project case study. The results of this study gauged the usability of the developed tool and corroborated the research premise