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Coronary artery disease (CAD) is reported as one of the most common sources of death all over the world. The presence of stenosis (plaque) in the coronary arteries results in the restriction of blood supply, leading to myocardial infarction. The current study investigates the influence of multi stenosis on hemodynamic properties in a patient-specific left coronary artery.

A three-dimensional model of the patient-specific left coronary artery was reconstructed based on computed tomography (CT) scan images using MIMICS-20 software. The diseased model of the left coronary artery was investigated, having the narrowing of 90% and 70% of area stenosis (AS) at the left anterior descending (LAD) and left circumflex (LCX), respectively.

The results indicate that the upstream region of stenosis experiences very high pressure for 90% AS during the systolic period of the cardiac cycle. The pressure drops maximum as the flow travels into the stenotic zone, and the high flow velocities were observed across the 90% AS. The higher wall shear stresses occur at the stenosis region, and it increases with the increase in the flow rate. It is found that the maximum wall shear stress across 90% AS is at the highest risk for rupture. A recirculation region immediately after the stenosis results in the further development of stenosis.

The current study provides evidence that there is a strong effect of multi-stenosis on the blood flow in the left coronary artery.

The purpose of this study is to solve convective diffusion equation analytically by considering appropriate boundary conditions and using the Taylor-Aris method to determine the solute concentration, the effective and relative axial diffusivities.

>An analysis has been conducted on how body acceleration affects the dispersion of a solute in blood flow, which is known as a Bingham fluid, within an artery. To solve the system of differential equations analytically while validating the target boundary conditions, the blood velocity is obtained.

The blood velocity is impacted by the presence of body acceleration, as well as the yield stress associated with Casson fluid and as such, the process of dispersing the solute is distracted. It graphically illustrates how the blood velocity and the process of solute dispersion are affected by various factors, including the amplitude and lead angle of body acceleration, the yield stress, the gradient of pressure and the Peclet number.

It is witnessed that the blood velocity, the solute concentration and also the effective and relative axial diffusivities experience a drop when either of the amplitude, lead angle or the yield stress rises.

Transaction cost becomes significant when one holds many securities in a large portfolio where capital allocations are frequently rebalanced due to variations in non-stationary statistical characteristics of the asset returns. The purpose of this paper is to employ a sparsing method to sparse the eigenportfolios, so that the transaction cost can be reduced and without any loss of its performance.

In this paper, the authors have designed pdf-optimized mid-tread Lloyd-Max quantizers based on the distribution of each eigenportfolio, and then employed them to sparse the eigenportfolios, so those small size orders may usually be ignored (sparsed), as the result, the trading costs have been reduced.

The authors find that the sparsing technique addressed in this paper is methodic, easy to implement for large size portfolios and it offers significant reduction in transaction cost without any loss of performance.

In this paper, the authors investigated the performance the sparsed eigenportfolios of stock returns in S&P500 Index. It is shown that the sparsing method is simple to implement and it provides high levels of sparsity without causing PNL loss. Therefore, transaction cost of managing a large size portfolio is reduced by employing such an efficient sparsity method.

Entrepreneurial ecosystem is a frontier issue in the field of enterprise strategy and entrepreneurship. As suggested by bottom of the pyramid (BOP) theory, entrepreneurs from base of the pyramid can gain the benefits of economic growth by obtaining equal entrepreneurial opportunities with appropriate support and motivation. However, theoretical framework to understand the ecosystem and help the people from the BOP to benefit from ecosystem is under-researched. Based on the investigation of the Taobao ecosystem case study, this paper developed a multi-layer framework to fill in the research gap.

This research adopts case study methodology for several reasons. First, case study methodology fits the explorative nature of this research to understand “what” and “how” a phenomenon happened (Yin, 2017). Second, case study research design can specify gaps or holes in existing theory with the ultimate goal of advancing theoretical explanations (Ridder, 2016). And third, it can provide researchers with contextual richness (Davison and Martinsons, 2016; Spigel, 2017).

Based on the literature review of the entrepreneurial ecosystem and the theory of the BOP, the initial framework of the inclusive entrepreneurial ecosystem is proposed. And then, based on the investigation of the Taobao village which is the typical inclusive entrepreneurial ecosystem, this paper explored how the inclusive entrepreneurial ecosystem emerges, develops and realises the co-creation between multiple actors. The emergence of Taobao village entrepreneurial ecosystem is because of the fact that ICT empowers BOP entrepreneurs. The development of entrepreneurial ecosystem presents a point-line-plane diffusion path, and co-creation to enhance inclusive entrepreneurship is realised by interaction and cooperation within social networks and integration of resources. Then, the framework of inclusive entrepreneurial ecosystem is further modified.

The complexity of entrepreneurial ecosystem facing BOP poses a major challenge to its actual operation. Therefore, it is necessary to study the driving factors of inclusive entrepreneurial ecosystems. In particular, ecosystem is a purposeful collaborative network of dynamic interactive systems, which has a set of changing dependencies in a given context. Research is still limited on socioeconomic actors’ interaction with each other in each stage to promote the evolution of entrepreneurial ecosystem. The extent to which they are intentionally designed or organically produced is still unclear, which is recommended for future study in this field.

It provides theoretical understanding on how to successfully form sustainable entrepreneurial ecosystem by integrating BOP entrepreneurs in value chain. The successful experience of Taobao village can provide contributions and implications for the management in practice. On the one hand, this can provide theoretical guidance for other countries and regions to build inclusive entrepreneurship ecosystems and help them to check and fill the gaps and build inclusive entrepreneurship ecosystems based on their local characteristics. On the other hand, this study provides theoretical guidance for solving the problem of poverty at the BOP, transforming the poor from the objects of help to successful entrepreneurs and thus realising regional sustainable development.

The significance of this study is to provide theoretical understanding on how to successfully form entrepreneurial ecosystem by practical investigation of entrepreneurial “habitat” at the BOP.

User-generated content (UGC) refers to semantic and behavioral traces created by users on various social media platforms. While several waves of platforms have come and gone, the long-term sustainability of UGC activities has become a critical question that bears significance for theoretical understanding and social media practices.

Based on a large and lengthy dataset of both blogging and microblogging activities of the same set of users, a multistate survival analysis was applied to explore the patterns of users' staying, switching and multiplatforming behaviors, as well as the underlying driving factors.

UGC activities are generally unsustainable in the long run, and natural attrition is the primary reason, rather than competitive switching to new platforms. The availability of leisure time, expected gratification and previous experiences drive users' sustainability.

The authors adopted actual behavioral data from two generations of platforms instead of survey data on users' switching intentions. Four types of users are defined: loyal, switcher, multiplatformer and dropout. As measured by the transitions among the four states, the different sustainability behaviors are thereby studied via an integrated framework. These two originalities bridge gaps in the literature and offer new insights into exploring user sustainability in social media.

In the present study, the thermal performance of engine radiator using conventional coolant and nanofluid is determined experimentally for the different flow rates. Further, the study implemented the Integrated Taguchi-GRA-PCA for optimising the heat transfer performance.

Nanofluids were prepared by taking ethylene glycol and water (25:75 by volume) with volume fraction of 0.01, 0.03 and 0.05% of TiO₂ nanopowder. Experimental Data were collected based on the design of experiments (DOE) L9 orthogonal array using Taguchi method. Statistical analysis via Grey relation analysis (GRA) and principal component analysis (PCA) were done to determine the role of experimental parameters on heat transfer coefficient and rate of heat transfer. Impact of three control factors, vol. % of TiO₂ concentration (φ), flow rate (LPH), and sonication time (min) on the performance characteristics on heat transfer coefficient and ratio of heat transfer rate is analysed to get the best combination of the parameters involved.

Analysis revealed the importance of parameters on heat transfer coefficient and can be sorted in terms of contributions from higher to lower degree. Finally, ANOVA test has been conducted to validate the effect of process parameters. The major controllable parameter is φ (concentration), contributing about 32.74%, then flow rate contributing 32.5% and finally sonication time showing small contribution of 18.57%.

A grey relational analysis integrated with principal component analyses (PCA) are implemented to get the optimum heat transfer coefficient and ratio of heat transfer rate. The novelty of the work is to adopt and implement the Integrated Taguchi-GRA-PCA first time for the purpose of thermal performance analysis of engine nano-coolant for radiator.

The regular occurrence of natural disasters elevates the need for an effective method to measure organizational preparedness in responding to the adverse impact of disasters. In this context, this paper presents a new decision support model to assess organizational disaster preparedness using both subjective and objective disaster preparedness criteria in a multi-criteria decision-making context.

The statistical variance method is integrated with the proximity value index (PVI) technique to determine priority scores in order to rank organizational disaster readiness.

The results of applying the integrated model developed herein enable decision-makers to make informed decisions for assigning priority ranking of organizational disaster preparedness in a simpler and more efficient way.

Human resource is the most impacting criterion affecting hospital preparedness in undertaking action to cure disaster victims.

This paper offers an exemplar of a simple and efficient decision-making process considering the subjectivity associated with decision-making as well as the objectivity of data used for determining the priority ranking of organizational disaster preparedness.

Integrating statistical variance method with the PVI technique is novel and it has not been presented in previous studies. In fact, this study is the first to integrate both methods for selecting the priority ranking of organizational disaster preparedness.