The advent of the fifth-generation (5G) technology has revolutionized the way we think about communication networks, enabling a plethora of new use cases and scenarios that were not possible with previous generations of wireless technology. The existing 5G communication networks predominantly rely on terrestrial communication infrastructure, which, however, exhibits several notable limitations such as capacity constraints, latency issues, and energy inefficiencies, necessitating this next-generation leap. The 6G aims to provide a comprehensive solution for a hyperconnected, intelligent, and immersive digital ecosystem, seamlessly integrating terrestrial, airborne, and spaceborne networks which is referred to as the space-air-ground-sea integrated network (SAGSIN). A traditional SAGSIN scenario mainly includes 3 segments: spaceborne network, airborne network, and terrestrial network. The classical SAGSIN architecture has shown remarkable capabilities in providing massive connectivity by integrating spaceborne, airborne, and terrestrial cellular networks, which, however, encounters inherent technical challenges against their respective practical implementation. On the other hand, the philosophy of near-space communications (NS-COM) is gradually emerging. The distinctive location of near space which is 20 ~ 100 km above Earth’s surface positiones at the core of the SAGSIN, thus allowing the NS-COM network to address the shortcomings of traditional spaceborne, terrestrial, and airborne networks. NS-COM present a promising addition to SAGSIN, making them the final piece of the SAGSIN puzzle.

A new method has been developed to create optical vortices with spatial-frequency patching metasurfaces. These "super-capacity perfect vector vortex beams" offer significantly increased data transmission capacity by utilizing multiple dimensions, including beam morphology, polarization azimuth, and ellipticity angle. The researchers believe this breakthrough could revolutionize optical information technology, enabling more secure and efficient data transmission.

In a paper published in Science Bulletin, researchers from Xiamen University, Zhengzhou University, and the Institute of Cultural Relics and Archaeology of Sanmenxia present evidence of the demographic history of Central Plain over the past three millennia by coanalyzing 30 newly reported high-quality ancient genomes with published reference data.

New research reveals the pivotal role of a mitochondrion-localized protein, PtoRFL30, in the wood formation of poplar trees.

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Two new quaternary Cr_xTi_0.75Mo_0.75V_1.5−xAlC₂ (x = 1.25, 1) MAXs and Cr_0.75Ti_0.75Mo_0.75V_0.75AlC₂ are synthesized by hot pressing. Interestingly, an unprecedented transition in M-site atomic occupancy from out-of-plane order to solid solution is observed along with the composition variation, which also increases the configurational entropy from medium- to high-entropy. Through experimental observation and theoretical calculation, the influence of the atomic distribution on their properties is analyzed. Eventually, about 40% increment on the Vickers hardness than that of the Cr₂TiAlC₂ and low thermal conductivities are detected from the three MAXs, which can be ascribed to the solid solution strengthening effects and the enhanced scattering of both electrons and phonons from the high-entropy structure.

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