ABSTRACT
3D bioprinting technology is a rapidly developing technique that employs bioinks containing biological materials and living cells to construct biomedical products. However, 3D-printed tissues are static, while human tissues are in real-time dynamic states that can change in morphology and performance. To improve the compatibility between in vitro and in vivo environments, an in vitro tissue engineering technique that simulates this dynamic process is required. The concept of 4D printing, which combines "3D printing + time" provides a new approach to achieving this complex technique. 4D printing involves applying one or more smart materials that respond to stimuli, enabling them to change their shape, performance, and function under the corresponding stimulus to meet various needs. This article focuses on the latest research progress and potential application areas of 4D printing technology in the cardiovascular system, providing a theoretical and practical reference for the development of this technology.
Subject(s)
Humans , Tissue Engineering/methods , Bioprinting/methods , Printing, Three-Dimensional , Cardiovascular System , Tissue ScaffoldsABSTRACT
The introduction of resin-based dental materials around the mid of the last century was a revolution in restorative dentistry. The early formulations were characterised by numerous problems like improper handling characteristics, polymerization shrinkage, improper marginal adaptation, inappropriate proximal contact and most importantly secondary caries and inadequate wear resistance. The need to improve shrinkage properties and wear resistance is obvious for dental composites and a vast number of attempts have been made to accomplish these aims. Based on recent clinical information, it appears that major successes have been achieved in reaching the goal. This article discusses the advances in resin restorative materials.
ABSTRACT
Since vibration highly influences the performance of vehicles, the effective improvment of vibration isolation has a great significance for enhancing the economy, balance, stability and reliability of vehicles. Based on the variable viscosity properties of magnetorheological(MR) fluids with the variation of a external magnetic flied resulted from adjustable and controllable electric current, a magnetorheological vibration isolator is developed. Through experiment and application, it is proved that the magnetorheological vibration isolator can highly increase vibration isolation efficiency.