[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Additive manufacturing (AM) alias 3D printing translates computer-aided design (CAD) virtual 3D models into physical objects. By digital slicing of CAD, 3D scan, or tomography data, AM builds objects layer by layer without the need for molds or machining. AM enables decentralized fabrication of customized objects on demand by exploiting digital information storage and retrieval via the Internet. The ongoing transition from rapid prototyping to rapid manufacturing prompts new challenges for mechanical engineers and materials scientists alike. Because polymers are by far the most utilized class of materials for AM, this Review focuses on polymer processing and the development of polymers and advanced polymer systems specifically for AM. AM techniques covered include vat photopolymerization (stereolithography), powder bed fusion (SLS), material and binder jetting (inkjet and aerosol 3D printing), sheet lamination (LOM), extrusion (FDM, 3D dispensing, 3D fiber deposition, and 3D plotting), and 3D bioprinting....

Polymers for 3D Printing and Customized Additive Manufacturing

Summary Type 1 diabetes is a chronic autoimmune disease characterised by insulin deficiency and resultant hyperglycaemia. Knowledge of type 1 diabetes has rapidly increased over the past 25 years, resulting in a broad understanding about many aspects of the disease, including its genetics, epidemiology, immune and β-cell phenotypes, and disease burden. Interventions to preserve β cells have been tested, and several methods to improve clinical disease management have been assessed. However, wide gaps still exist in our understanding of type 1 diabetes and our ability to standardise clinical care and decrease disease-associated complications and burden. This Seminar gives an overview of the current understanding of the disease and potential future directions for research and care.

Type 1 diabetes

Organ printing can be defined as layer-by-layer additive robotic biofabrication of three-dimensional functional living macrotissues and organ constructs using tissue spheroids as building blocks. The microtissues and tissue spheroids are living materials with certain measurable, evolving and potentially controllable composition, material and biological properties. Closely placed tissue spheroids undergo tissue fusion - a process that represents a fundamental biological and biophysical principle of developmental biology-inspired directed tissue self-assembly. It is possible to engineer small segments of an intraorgan branched vascular tree by using solid and lumenized vascular tissue spheroids. Organ printing could dramatically enhance and transform the field of tissue engineering by enabling large-scale industrial robotic biofabrication of living human organ constructs with "built-in" perfusable intraorgan branched vascular tree. Thus, organ printing is a new emerging enabling technology paradigm which represents a developmental biology-inspired alternative to classic biodegradable solid scaffold-based approaches in tissue engineering.

Organ Printing: Tissue Spheroids as Building Blocks

An overview on 3D printing technology: Technological, materials, and applications

3D bioprinting of tissues and organs for regenerative medicine.

Global climate change is a change in the long-term weather patterns that characterize the regions of the world. Scientists state unequivocally that the earth is warming. Natural climate variability alone cannot explain this trend. Human activities, especially the burning of coal and oil, have warmed the earth by dramatically increasing the concentrations of heat-trapping gases in the atmosphere. The more of these gases humans put into the atmosphere, the more the earth will warm in the decades and centuries ahead. The impacts of warming can already be observed in many places, from rising sea levels to melting snow and ice to changing weather patterns. Climate change is already affecting ecosystems, freshwater supplies, and human health. Although climate change cannot be avoided entirely, the most severe impacts of climate change can be avoided by substantially reducing the amount of heat-trapping gases released into the atmosphere. However, the time available for beginning serious action to avoid severe global consequences is growing short. This paper reviews assessing of such climate change impacts on various components of the ecosystem such as air, water, plants, animals and human beings, with special emphasis on economy. The most daunting problem of global warming is also discussed. This paper, further reviews the mitigation measures, with a special focus on carbon sequestration and clean development mechanism (CDM). The importance of synergy between climate change mitigation and adaptation has been discussed. An overview of the relationship between economy and emissions, including Carbon Tax and Emission Trading and the policies are also presented.

A review of climate change, mitigation and adaptation

Agricultural products such as coffee, tobacco, tea, fruit, cocoa beans, rice, nuts, and timber generally require drying through a consistent application of relatively low heat. Traditionally, crop drying has been accomplished by burning wood and fossil fuels in ovens or open air drying under screened sunlight. These methods, however, have their shortcomings. The former is expensive and damages the environment and the latter is susceptible to the variety and unpredictability of the weather. Solar crop drying is a happy medium between these two methods and it dries crops with more efficiency, uniformity, and less expense. A solar crop drying system does not solely depend on solar energy to function; it combines fuel burning with the energy of the sun, thus reducing fossil fuel consumption. In this paper, the status of solar drying technologies in developing countries is presented. The various designs of solar dryers, its types and performance analysis are reviewed. Special attention is given to the solar drying technologies that facilitate drying of crops in off-sunshine hours. The solar dryers specifically designed or tested using specific crops like the vegetable dryer, fruit dryer, grain dryer, grape dryer, and so on are also reviewed with details about the specifications and the results. In short, the state of art technologies and development of solar dryers are presented in this paper.

A review of solar drying technologies

Nerve guide conduits for peripheral nerve injury repair: A review on design, materials and fabrication methods.

The skin is the largest organ of the body, having a complex multi-layered structure and guards the underlying muscles, bones, ligaments, and internal organs. It serves as the first line of defence to any external stimuli, hence it is the most vulnerable to injury and warrants the need for rapid and reliable regeneration methods. Tissue engineered skin substitutes help overcome the limitations of traditional skin treatment methods, in terms of technology, time, and cost. While there is commendable progress in the treating of superficial wounds and injuries with skin substitutes, treatment of full-thickness injuries, especially with third or fourth degree burns, still looks murkier. Engineering multi-layer skin architecture, conforming to the native skin structure is a tougher goal to achieve with the current tissue engineering methods, if not impossible, restoring all the functions of the native skin. The testing of drugs and cosmetics is another area, where engineered skins are very much needed, with bans being imposed on product testing on animals. Given this greater need, 3D bioprinting is a promising technology that can achieve rapid and reliable production of biomimetic cellular skin substitutes, satisfying both clinical and industrial needs. This paper reviews all aspects related to the 3D bioprinting of skin, right from imaging the injury site, 3D model creation, biomaterials that are used and their suitability, types of cells and their functions, actual bioprinting technologies, along with the challenges and future prospects.

https://iopscience.iop.org/article/10.1088/1758-5090/8/3/032001/pdf

Sanjairaj Vijayavenkataraman

Papers

3D bioprinting of tissues and organs for regenerative medicine.

A review of climate change, mitigation and adaptation

A review of solar drying technologies

Nerve guide conduits for peripheral nerve injury repair: A review on design, materials and fabrication methods.

3D bioprinting of skin: a state-of-the-art review on modelling, materials, and processes