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The purpose of this paper is to design and implement a new manufacturing process for biomedical products by removing an electro‐polishing (EP) operation. The research was performed in a major North American orthopedic industry.

Value stream mapping is used to analyze and identify the waste in the current manufacturing process of bone screw. Upon formulation of new (to‐be) process, it has been validated to meet the regulatory requirements for the products through autoclave, endotoxin level, and biomechanical tests. Statistical tests are performed to compare the EP versus non‐EP process.

The study has shown that the EP operation was not only redundant to bone screw manufacturing but also created other problems such as quality and production delays. The overall production lead time of the screws has been reduced from 17 to 4.5 days.

Scope of the pilot study was limited to stainless steel screw. In future, the company plans to perform similar studies on other material types.

The EP operation is very common in the orthopedic industry. However, as found in this paper, it is not required for every component. The bone screw case study presented in the paper offers a huge saving for the company by eliminating a “wasteful” activity from the manufacturing process.

Biomedical products pose unique challenges to the process optimization efforts because of their stringent government and industry requirements. This paper provides an original case study of design, validation, and testing of an improved manufacturing process for a biomedical product.

The purpose of this paper is to evaluate the feasibility of direct fabrication of lunar/Martian regolith simulant parts, in a freeform environment, using Laser Engineering Net Shaping (LENS™) – an additive manufacturing technology.

Bulk lunar regolith simulant structures were fabricated using a LENS™‐750. Dense parts without any macroscopic defects were produced at a laser power of 50W, a scan speed of 20 mm/s, and a powder feed rate of 12.36 g/min. The laser processed parts were characterized using X‐ray diffraction, differential scanning calorimetry, scanning electron microscope and X‐ray photoelectron spectroscopy to evaluate the influence of laser processing on the microstructure, constituent phases and chemistry of lunar regolith simulant.

A combination of laser parameters resulting in a 2.12 J/mm² laser energy appeared to be ideal for generating a melt pool necessary for lunar regolith powder deposition without excessive liquid pool spreading and cracking of solidified parts. The results show that LENS™ based laser processing transformed crystalline regolith into nanocrystalline and/or amorphous regolith structures as a result of complete melting followed by resolidification. Laser processing also resulted in marginal changes in the composition of the regolith.

Establishment of a lunar/Martian outpost necessitates the development of methods to utilize in situ mineral resources for various construction and resource extraction applications. Fabrication technologies are critical for habitat structure development, as well as repair and replacement of tools and parts at the outpost. Current experimental results presented in the paper clearly demonstrate that net shape regolith simulant parts can be fabricated using LENS™ by exploiting its capabilities.

This paper aims to present a comprehensive review of the laser engineered net shaping (LENS) process in an attempt to provide the reader with a deep understanding of the controllable and fixed build parameters of metallic parts. The authors discuss the effect and interplay between process parameters, including: laser power, scan speed and powder feed rate. Further, the authors show the interplay between process parameters is pivotal in achieving the desired microstructure, macrostructure, geometrical accuracy and mechanical properties.

In this manuscript, the authors review current research examining the process inputs and their influences on the final product when manufacturing with the LENS process. The authors also discuss how these parameters relate to important build aspects such as melt-pool dimensions, the volume of porosity and geometry accuracy.

The authors conclude that studies have greatly enriched the understanding of the LENS build process, however, much studies remains to be done. Importantly, the authors reveal that to date there are a number of detailed theoretical models that predict the end properties of deposition, however, much more study is necessary to allow for reasonable prediction of the build process for standard industrial parts, based on the synchronistic behavior of the input parameters.

This paper intends to raise questions about the possible research areas that could potentially promote the effectiveness of this LENS technology.

Buongiorno’s type nanofluid mass and heat transport appearances inside a cavity filled with gyrotactic microorganisms by captivating thermal radiation is analyzed in the present work. Finite element investigation is instigated to examine the converted momentum, temperature, concentration of microorganisms and concentration of nanofluid equations numerically.

Finite element investigation is instigated to examine the converted momentum, temperature, concentration of microorganisms and concentration of nanofluid equations numerically.

The sway of these influenced parameters on standard rates of heat transport, nanoparticles Sherwood number and Sherwood number of microorganisms is also illustrated through graphs. It is perceived that the rates of heat transport remarkably intensifies inside the cavity region with amplifying thermophoresis number values.

The research work carried out in this paper is original and no part is copied from others’ work.

The study aims to understand how corporate social responsibility (CSR) and happiness are used together in various research studies to serve the ultimate goal of corporate sustainability (CS), which in turn contributes to sustainable development.

A systematic literature review (SLR) was made using Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) method in the two most-reputable databases of Web of Science (WoS) and Scopus, revealing a final list of 54 studies to analyse.

The review concludes that the literature on CSR and happiness provides three main findings: first, concerning the pillars of sustainability, most of the studies concentrate on people, neglecting the planet and profit, second, employees are subject to the highest number of studies as the target of CSR initiative and third, almost all studies employed the hedonic aspect of happiness in CSR literature.

This particular research finding points to the need for developing a comprehensive framework to assess stakeholder happiness from both hedonic and eudaimonic aspects from a CSR perspective which is then represented under the three pillars of sustainability.

To contribute to the ultimate goal of CS, management would design CSR initiatives for all stakeholders to increase both hedonic and eudaimonic happiness of them.

The literature provides reviews of research in CSR and happiness separately; however, there is not any research revealing how these two concepts are used together in studies and how this association could be read to serve the goal of CS.

The purpose of this paper is to examine the relationship between an individual's social capital context and entrepreneurship using a multi-level modelling framework.

This paper uses data from 87,007 individual level observations across 428 regions in 37 countries. The data comes from the 2010 and 2016 Life in Transition Surveys. The paper uses a principal component analysis to identify the different dimensions of an individual's social capital context. Subsequently, a multi-level model is employed examining the relationship between the components of an individual's social capital context and entrepreneurship (which is proxied by an individual's attempt to set up a business), whilst controlling for both country and regional effects.

Greater levels of networking, informal connections and tolerance of others have a significant positive relationship with entrepreneurial activity. Trust of institutions and others have a negative relationship with entrepreneurial activity. Regional and country differences are also important for entrepreneurship, demonstrating the importance of the multi-level and social contextual environment for business development.

Firstly, the authors present a broad, but comprehensive social contextual framework incorporating many measures of social capital when examining the importance of social capital for business development. Secondly, the work provides interesting results on the “bright and dark sides of trust” for entrepreneurship, answering calls for improved understandings on the positive and negative relationships between social capital and entrepreneurial activity. Thirdly, the paper extends the burgeoning but limited number of studies that examine the multi-level contextual environment of entrepreneurial activities.

The purpose of this paper is to present a new method for representing heterogeneous materials using nested STL shells, based, in particular, on the density distributions of human bones.

Nested STL shells, called Matryoshka models, are described, based on their namesake Russian nesting dolls. In this approach, polygonal models, such as STL shells, are “stacked” inside one another to represent different material regions. The Matryoshka model addresses the challenge of representing different densities and different types of bone when reverse engineering from medical images. The Matryoshka model is generated via an iterative process of thresholding the Hounsfield Unit (HU) data using computed tomography (CT), thereby delineating regions of progressively increasing bone density. These nested shells can represent regions starting with the medullary (bone marrow) canal, up through and including the outer surface of the bone.

The Matryoshka approach introduced can be used to generate accurate models of heterogeneous materials in an automated fashion, avoiding the challenge of hand-creating an assembly model for input to multi-material additive or subtractive manufacturing.

This paper presents a new method for describing heterogeneous materials: in this case, the density distribution in a human bone. The authors show how the Matryoshka model can be used to plan harvesting locations for creating custom rapid allograft bone implants from donor bone. An implementation of a proposed harvesting method is demonstrated, followed by a case study using subtractive rapid prototyping to harvest a bone implant from a human tibia surrogate.

This paper aims to explore the local knowledge on climate change, its impacts and the responses they are making at the household or community level to deal with the changes on the basis of their experiences and perceptions.

The study was based on household survey conducted with one male and one female respondent in 202 households. Alongside, series of focused group discussions were conducted with local people to capture the perception on about climate change, its impacts and adaptation strategies applied to enhance their resilience capacity to changing climate. Rainfall and temperature data were collected from Department of Hydrology and Meteorology (DHM) for seven and four different stations, respectively, within Kathmandu Valley and analyzed to understand the climatic trend.

The perception of most of the local people on changes in temperature was almost in line with the recorded long-term climatic trend both showing an increasing trend, whereas the perception of decreasing both monsoon and non-monsoon rainfall did not match with the recorded data as the rainfall data analysis did not reflect any clear long-term pattern. People have been facing several impacts such as decrease in water sources, decrease in agricultural crop production, increase in new crop pest and weeds in agricultural crops. Local people are responding to these impacts as per their own skills and traditional knowledge.

This is totally original research article and the impacts and adaptations measures documented in this article may represent the case of peri-urban areas of least developed countries like Nepal.

The purpose of this paper is to assess the effects of prompt corrective action on bank risk and returns in an empirical framework.

The paper uses a difference-in-difference specification to analyse whether and how PCA affects bank risk and returns. As part of robustness, the analysis also uses a fixed effects specification with Driscoll–Kraay standard errors to account for serial correlation and cross-sectional dependence.

The findings reveal that banks under PCA framework contribute less to systemic risk and exhibit higher market valuation. These findings differ across recapitalised versus non-recapitalised banks and for banks with differing asset quality, capital and profitability. The overall price impact is a decline in lending rates and deposit costs.

To the best of the author’s understanding, this is one of the early studies in the Indian context to carefully examine the linkage between PCA and bank behaviour.

The purpose of this paper is to establish a methodology for the design and development of patient-specific elbow implant with an elastic modulus close to that of the human bone. One of the most preferred implant material is titanium alloy which is about 8 to 9 times higher in strength than that of the human bone and is the closest than other metallic biomedical materials.

The methodology begins with the design of the implant from patient-specific computed tomography information and incorporates the manufacturing of the implant via a novel rapid prototyping assisted microwave sintering process.

The elastic modulus and the flexural strength of the implant were observed to be comparable to that of human elbow bones. The fatigue test depicts that the implant survives the one million cycles under physiological loading conditions. Other mechanical properties such as impact energy absorption, hardness and life cycle tests were also evaluated. The implant surface promotes human cell growth and adhesion and does not cause any adverse or undesired effects i.e. no cytotoxicity.

Stress shielding, and therefore, aseptic loosening of the implant shall be avoided. In the event of any trauma post-implantation, the implant would not hurt the patient.

The present study describes a methodology for the first time to be able to obtain the strength required for the medical implant without sacrificing the fatigue life requirement.