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The main purpose of this research work is to study the effect of poly lactic acid (PLA) addition into poly (e-caprolactone) (PCL) matrices, as well the influence of the mixing process on the morphological, thermal, chemical, mechanical and biological performance of the 3D constructs produced with a novel biomanufacturing device (BioCell Printing).

Two mixing processes are used to prepare PCL/PLA blends, namely melt blending and solvent casting. PCL and PCL/PLA scaffolds are produced via BioCell Printing using a 300-μm nozzle, 0/90° lay down pattern and 350-μm pore size. Several techniques such as scanning electron microscopy (SEM), simultaneous thermal analyzer (STA), nuclear magnetic resonance (NMR), static compression analysis and Alamar BlueTM are used to evaluate scaffold's morphological, thermal, chemical, mechanical and biological properties.

Results show that the addition of PLA to PCL scaffolds strongly improves the biomechanical performance of the constructs. Additionally, polymer blends obtained by solvent casting present better mechanical and biological properties, compared to blends prepared by melt blending.

This paper undertakes a detailed study on the effect of the mixing process on the biomechanical properties of PCL/PLA scaffolds. Results will enable to prepare customized PCL/PLA scaffolds for tissue engineering applications with improved biological and mechanical properties, compared to PCL scaffolds alone. Additionally, the accuracy and reproducibility of by the BioCell Printing enables to modulate the micro/macro architecture of the scaffolds enhancing tissue regeneration.

This paper aims to present a solid freeform fabrication-based in situ three-dimensional (3D) printing method. This method enables simultaneous cross-linking alginate at ambient environmental conditions (temperature and pressure) for 3D-laden construct fabrication. The fabrication feasibility and potentials in biomedical applications were evaluated.

Fabrication feasibility was evaluated as the investigation of fabrication parameters on strut formability (the capability to fabricate a cylindrical strut in the same diameter as dispensing tip) and structural stability (the capability to hold the fabricated 3D-laden construct against mechanical disturbance). Potentials in biomedical application was evaluated as the investigation on structural integrity (the capability to preserve the fabricated 3D-laden construct in cell culture condition).

Strut formability can be achieved when the flow rate of alginate suspension and nozzle travel speed are set according to the dispensing tip size, and extruded alginate was cross-linked sufficiently. A range of cross-linking-related fabrication parameters was determined for sufficient cross-link. The structural stability and structural integrity were found to be controlled by alginate composition. An optimized setting of the alginate composition and the fabrication parameters was determined for the fabrication of a desired stable scaffold with structural integrity for 14 days.

This paper reports that in situ 3D printing is an efficient method for 3D-laden construct fabrication and its potentials in biomedical application.

The purpose of this paper is to present the development of a technical procedure for the manufacturing of medical implant prototypes.

The paper was performed on a new hip implant design and manufactured with different metallic alloys F75 (ASTM) commonly used in biomedical applications. Dimensional parameters between the computer‐aided design (CAD) geometry and the prototypes and surface roughness for different casting alloy were compared. A CAD model was used for machining of a prototype. Room temperature vulcanising (RTV) rubber moulds allowed the manufacturing of wax models of the femoral prosthesis. A specific lost‐wax casting (LWC) technology was used to manufacture prototypes for in vitro tests. The final geometry was dimensionally controlled using different type of parameters (performance, average, standard, maximum and minimum deviations), surface roughness (Ra, Rt and Rp) were measured for all prototypes.

To obtain a small number of implants, RTV rubber vacuum casting technique can be used to obtain lost wax models with good dimensional stability. No significant dimensional differences were observed relatively to the virtual model. However, the temperature of the wax and the rubber mould were important parameters to obtain good quality wax models. Surface roughness was different for different alloys.

The design and development of a new hip femoral prosthesis prototype based on rapid tooling techniques to manufacture LWC prototypes is suitable for clinical trials.

This paper describes a biomanufacturing methodology to manufacture biomedical implant prototypes.

Radiotherapy relies on the delivery of radiation to cancer cells with millimetre accuracy, and immobilisation of patients is essential to minimise unwanted damage to surrounding healthy cells due to patient movement. Traditional thermoformed face masks can be uncomfortable and stressful for patients and may not be accurately fitted. The purpose of this study was to use 3D scanning and additive manufacturing to digitise this workflow and improve patient comfort and treatment outcomes.

The head of a volunteer was scanned using an Artec Leo optical scanner (Artec, Luxembourg) and ANSYS (Ansys, Canonsburg, USA) software was used to make two 3D models of the mask: one with a nose bridge and one open as would be used with optical surface guidance. Data based on measurements from ten pressure sensors around the face was used to perform topology optimisation, with the best designs 3D printed using fused deposition modelling (FDM) and tested on the volunteer with embedded pressure sensors.

The two facemasks proved to be significantly different in terms of restricting head movement inside the masks. The optimised mask with a nose bridge effectively restricted head movement in roll and yaw orientations and exhibited minimal deformation as compared to the open mask design and the thermoformed mask.

The proposed workflow allows customisation of masks for radiotherapy immobilisation using additive manufacturing and topology optimisation based on collected pressure sensor data. In the future, sensors could be embedded in masks to provide real-time feedback to clinicians during treatment.

This paper aims to describe the control software of a novel manufacturing system called plasma-assisted bio-extrusion system (PABS), designed to produce complex multi-material and functionally graded scaffolds for tissue engineering applications. This fabrication system combines multiple pressure-assisted and screw-assisted printing heads and plasma jets. Control software allows the users to create single or multi-material constructs with uniform pore size or pore size gradients by changing the operation parameters, such as geometric parameters, lay-down pattern, filament distance, feed rate and layer thickness, and to produce functional graded scaffolds with different layer-by-layer coating/surface modification strategies by using the plasma modification system.

MATLAB GUI is used to develop the software, including the design of the user interface and the implementation of all mathematical programing for both multi-extrusion and plasma modification systems.

Based on the user definition, G programing codes are generated, enabling full integration and synchronization with the hardware of PABS. Single, multi-material and functionally graded scaffolds can be obtained by manipulating different materials, scaffold designs and processing parameters. The software is easy to use, allowing the efficient control of the PABS even for the fabrication of complex scaffolds.

This paper introduces a novel additive manufacturing system for tissue engineering applications describing in detail the software developed to control the system. This new fabrication system represents a step forward regarding the current state-of-the-art technology in the field of biomanufacturing, enabling the design and fabrication of more effective scaffolds matching the mechanical and surface characteristics of the surrounding tissue and enabling the incorporation of high number of cells uniformly distributed and the introduction of multiple cell types with positional specificity.

This paper aims to report a detailed study regarding the influence of process parameters on the morphological/mechanical properties of poly(ε‐caprolactone) (PCL) scaffolds manufactured by using a novel extrusion‐based system that is called BioExtruder.

In this study the authors focused investigations on four parameters, namely the liquefier temperature (LT), screw rotation velocity (SRV), deposition velocity (DV) and slice thickness (ST). Scaffolds were fabricated by employing three different values of each parameter. Through a series of trials, scaffolds were manufactured varying iteratively one parameter while maintaining constant the other ones. The morphology of the structures was investigated using a scanning electron microscope (SEM), whilst the mechanical performance was assessed though compression tests.

Experimental results highlight a direct influence of the process parameters on the PCL scaffolds properties. In particular, DV and SRV have the highest influence in terms of road width (RW) and consequently on the porosity and mechanical behaviour of the structures.

The effect of process and design parameters on the biological response of scaffolds is currently under investigation.

The output of this work provides a major insight into the effect of process parameters on the morphological/mechanical properties of PCL scaffolds. Moreover, the potential and feasibility of this novel extrusion‐based system open a new opportunity to study how structural features may influence the characteristics and performances of the scaffolds, enabling the development of integrated biomechanical models that can be used in CAD systems to manufacture customized structures for tissue regeneration.

The purpose of this paper is to explore and investigate the mechanical as well as bacterial characteristics of chemically treated waste natural fiber inserted three-dimensional structures (NFi3DS) produced with fused filament deposition (FFD) for biomedical applications.

In this work, a novel approach has been used for developing the customized porous structures particularly for scaffold applications. Initially, raw animal fibers were collected, and thereafter, the chemical treatment has been performed for making their wise utility in biomedical structures. For this purpose, silk fiber and sheep wool fibers were used as laminations, whereas polylactic acid was used as matrix material. A low-cost desktop time additive manufacturing setup was used for making the customized and porous parts by considering type of fiber, number of laminates, infill density and raster angle as input parameters.

The results obtained after using design of experimental technique highlighted that output characteristics (such as dimensional accuracy, hardness, three-point bending strength and bacterial test) are influenced by input parameters, as reported in the obtained signal/noise plots and analysis of variance. Optimum level of input parameters has also been found through Taguchi L9 orthogonal array, for single parametric optimization, and teaching learning-based algorithm and particle swarm optimization, for multiple parametric optimization. Overall, the results of the studies supported the use of embedded structures for scaffold-based biomedical applications.

Presently, NFi3DS were produced by using the hand-lay-based manual approach that affected the uniform insert’s distribution and thickness. It is advised to use the automatic fiber placement system, synced with a three-dimensional printer, to achieve greater geometrical precision.

As both natural fibers and polymer matrix used in this work are well established for their biological properties, hence the methodology explored in this work will help the practitioners/academicians in developing highly compatible scaffold structures.

The present work defines a new practice where the researchers can use natural fibers to reduce the cost associated with fabrication of customized scaffold prints.

The development of natural fiber embedded FFD-based structures is not yet explored for their feasibility in biomedical applications.

In 2004 and 2007, the Kauffman Foundation awarded 18 universities and colleges $3–5 million dollars each to develop radiant model entrepreneurship education programs and campus-wide entrepreneurial ecosystems. Grant recipients were required to have a senior level administrator to oversee the program who reported to the Provost, President, or Chancellor. Award recipients included Syracuse University (2007) and the University of Rochester (2004). Cornell was not a Kauffman campus. This chapter explores three case studies in the radiant model of university-wide entrepreneurship education as deployed at Cornell University, The University of Rochester, and Syracuse University. The authors examine the history, accelerators, and challenges of the radiant model of university-wide entrepreneurship education.

The BRITE program at North Carolina Central University fosters the intellectual development of students and provides them with exposure to extensive undergraduate research experiences. This hands-on training along with a rigorous academic program, advising, faculty mentoring, and career counseling adequately prepare students for careers in biotechnology, biopharmaceutical, or pharmaceutical industries and/or advanced degree programs. As a result, students are thoroughly prepared for scientific careers and to contribute to society as productive scientists. To date, there has been a high placement rate for graduates from the BRITE program. Similarly, we have also observed increasing rates of enrollment, retention, and graduation. The BRITE program is a model of success for educating future generations of scientists by infusing undergraduate research into HBCU curricula and clearly demonstrates the significance undergraduate research plays in preparing students for their professional careers.