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The purpose of this paper is to present a topology-based tissue scaffold design methodology to accurately represent the heterogeneous internal architecture of tissues/organs.

An image analysis technique is used that digitizes the topology information contained in medical images of tissues/organs. A weighted topology reconstruction algorithm is implemented to represent the heterogeneity with parametric functions. The parametric functions are then used to map the spatial material distribution following voxelization. The generated chronological information yields hierarchical tool-path points which are directly transferred to the three-dimensional (3D) bio-printer through a proposed generic platform called Application Program Interface (API). This seamless data corridor between design (virtual) and fabrication (physical) ensures the manufacturability of personalized heterogeneous porous scaffold structure without any CAD/STL file.

The proposed methodology is implemented to verify the effectiveness of the approach and the designed example structures are bio-fabricated with a deposition-based bio-additive manufacturing system. The designed and fabricated heterogeneous structures are evaluated which shows conforming porosity distribution compared to uniform method.

In bio-fabrication process, the generated bio-models with boundary representation (B-rep) or surface tessellation (mesh) do not capture the internal architectural information. This paper provides a design methodology for scaffold structure mimicking the native tissue/organ architecture and direct fabricating the structure without reconstructing the CAD model. Therefore, designing and direct bio-printing the heterogeneous topology of tissue scaffolds from medical images minimize the disparity between the internal architecture of target tissue and its scaffold.

This study aims to develop a specialized and economically feasible educational model using a combination of conventional approach and additive technology with a precision that proves to be sufficient for educational use. With the use of computer-aided design/computer-aided manufacturing models in educational stages, the possibility of infectious diseases transmission can be significantly reduced.

The proposed process involves the planning and development of specialized anatomical three-dimensional (3D) models and associated structures using omnipresent additive technologies. A short survey was conducted among dental students about their knowledge of applying additive technologies in dental medicine and their desire to implement such technologies into existing curricula.

The results revealed how an educational 3D model can be developed by optimizing the mesh parameters to reduce the total number of elements while maintaining the quality of the geometric structure. The survey results demonstrated that the willingness to adapt to new technologies is increasing (p < 0.001) among students with a higher level of education. A series of recent studies have indicated that the lack of knowledge and the current skill gap remain the most significant barriers to the wider adoption of additive manufacturing.

An economically feasible, realistic anatomical educational model in the field of dental medicine was established. Additive technology is a key pillar of new specialized-knowledge digital skills for the enhancement of dental training.

The novelty of this study is the introduction of a 3D technology for promoting an economically feasible model, without compromising the quality of dental education.

The design process of a bio-model involves multiple factors including data acquisition technique, material requirement, resolution of the printing technique, cost-effectiveness of the printing process and end-use requirements. This paper aims to compare and highlight the effects of these design factors on the printing outcome of bio-models.

Different data sources including engineering drawing, computed tomography (CT), and optical coherence tomography (OCT) were converted to a printable data format. Three different bio-models, namely, an ophthalmic model, a retina model and a distal tibia model, were printed using two different techniques, namely, PolyJet and fused deposition modelling. The process flow and 3D printed models were analysed.

The data acquisition and 3D printing process affect the overall printing resolution. The design process flows using different data sources were established and the bio-models were printed successfully.

Data acquisition techniques contained inherent noise data and resulted in inaccuracies during data conversion.

This work showed that the data acquisition and conversion technique had a significant effect on the quality of the bio-model blueprint and subsequently the printing outcome. In addition, important design factors of bio-models were highlighted such as material requirement and the cost-effectiveness of the printing technique. This paper provides a systematic discussion for future development of an engineering design process in three-dimensional (3D) printed bio-models.

Aging is a continuous process of growth and decay, both of which start at birth and continue throughout life. Activity develops muscles and neurons; inactivity atrophies them. Here we propose lifelong creative activity as a method to deal with aging. Decreased creative and learning capacity is a self‐fulfilling prophecy. Changing personal perceptions and expectations can promote health care and productive behavior.

This paper aims to quantify the loss (or leakage) of organic cattle to conventional value chains in Ireland and assess its economic and environmental impacts.

The paper adopts a Bio-economy Input-Output (BIO) model, a quantitative economic model representing the interdependencies between different sectors of the economy, to assess the economic and environmental impacts of organic leakage in the Irish beef sector.

The study reveals that 17% of organic cattle aged under 1 year old leave the organic value chain, leaking to the conventional market as a result of imbalances in the development of the beef value chain. The economic cost of this organic leakage is 5.66 million euros. Leakage also has environmental effects because of changes in lifecycle methane and nitrogen emissions based on longer finishing times on organic farms and chemical fertilisers applied on conventional farms. The organic leakage results in a reduction of 82 tons of methane emission and 52 additional tons of nitrogen emission, which leads to 11,484 tons of net global warming potential (GWP) for a 100-year time horizon.

Because of data availability, the research focussed on the baseline year 2015, which had national data available for disaggregation in Ireland. Therefore, researchers are encouraged to assess the economic and environmental impacts when more recent data are available and to analyse the change in the impacts over the years.

This study contributes to the discussion on organic conversion and provides valuable insights for stakeholders, especially policymakers, for the design of future organic schemes.

This is the first paper to assess organic leakage in the beef sector.

Design methods for medical rapid prototyping (RP) of personalized cranioplasty implants are presented in this paper. These methods are applicable to model cranioplasty implants for all types of the skull defects including beyond‐midline and multiple defects. The methods are based on two types of anatomical data, solid bone models (STereoLithography files – STL) and bone slice contours (Initial Graphics Exchange Specification – IGES and StrataSys Layer files – SSL). The bone solids and contours are constructed based on computed tomography scanning data, and these data are generated in medical image processing and STL slicing packages.

Over the past decade, biofuels production in the European Union and the United States has boomed – much of this due to government mandates and subsidies. The United States has now surpassed Brazil as the world's leading producer of ethanol. The economic and environmental impact of these biofuel programs has become an important question of public policy. Due to the complex intersectoral linkages between biofuels and crops, livestock as well as energy activities, CGE modeling has become an important tool for their analysis. This chapter reviews recent developments in this area of economic analysis and suggests directions for future research.

This paper aims to describe computer‐aided design and rapid prototyping (RP) systems for the preoperative planning and fabrication of custom‐made implant.

A patient with mandible defect underwent reconstruction using custom‐made implant. 3D models of the patient's skull are generated based on computed tomography image data. After evaluation of the 3D reconstructed image, it was identified that some bone fragment was moved due to the missing segment. During the implant design process, the correct position of the bone fragment was defined and the geometry of the custom‐made implant was generated based on mirror image technique and is fabricated by a RP machine. Surgical approach such as preoperative planning and simulation of surgical procedures was performed using the fabricated skull models and custom‐made implant.

Results show that the stereolithography model provided an accurate tool for preoperative, surgical simulation.

The methods described above suffer from the expensive cost of RP technique.

This method allows accurate fabrication of the implant. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

The method improves the reconstructive surgery and reduces the risk of a second intervention, and the psychological stress of the patient will be eliminated.