A new strategy for strengthening polymer materials could lead to more durable plastics and cut down on plastic waste, MIT and Duke University researchers report.

Mechanical engineering researchers at the UCLA Samueli School of Engineering have designed a mattress that helps prevent bedsores by alternating pressure across the body and, at times, increasing peak pressure rather than reducing it to restore blood flow.

With the rapid development of multispectral detection technology, the demand for multi-band, multifunctional, and compatible infrared camouflage in complex military environments is becoming increasingly urgent. Traditional infrared camouflage technology mainly focuses on the control of single-band emissivity, and the static design is hard to match with the surrounding environment and actual needs. When the target has a significant difference in emissivity compared to the environment, low-emissivity camouflage may expose itself due to abnormal thermal signals. At the same time, existing technologies often overlook the needs of multispectral compatibility, such as the lack of comprehensive management of heat accumulation, laser stealth, and visible light camouflage when achieving infrared camouflage. The adaptability mechanisms in nature provide new insights, such as the unique spectral characteristics of Rosaceae plants. Their band response patterns offer significant inspiration for the design of tunable and compatible visible light camouflage, as well as infrared and laser stealth. The emergence and application of phase change materials provide a possibility to solve this key problem. The reversible switching between crystalline and amorphous states supports the regulation of optical parameters, enabling multifunctional compatible stealth and camouflage in infrared, laser and visible light bands.

Metasurfaces are artificially designed two-dimensional structures composed of a large number of subwavelength-sized units arranged periodically or aperiodically. They can overcome the limitations of natural materials and endow electromagnetic waves with unique manipulation capabilities. The motivation for metasurface research stems from the core challenges of wireless communication: optimizing signal coverage and quality in complex electromagnetic environments.

With the increasing demand for high-frequency bands (millimeter-wave and terahertz) and large-scale connectivity in 5G/6G communications, traditional technologies face challenges such as high hardware complexity, excessive power consumption, and severe channel interference. Due to their low power consumption, low cost, and easy deployment, metasurfaces have emerged as an ideal solution to these problems. 

In particular, the concept of digital-coded metasurfaces, proposed in 2014, introduced programmable elements (such as PIN diodes) to discretize electromagnetic properties into "0/1" digital states. Combined with controllers like FPGAs, these metasurfaces enable real-time dynamic regulation of electromagnetic waves. This breakthrough has transformed metasurfaces from “fixed-function materials” into “intelligent electromagnetic surfaces”, capable of dynamically optimizing wireless channels and even directly participating in signal modulation and transmission.