Ultralight aerogel sphere composed of nanocellulose-derived carbon nanofiber and graphene for excellent electromagnetic wave absorption

A novel type of three-dimensional ultralight aerogel sphere,consisting of one-dimensional nanocellulose-derived carbon fibers and two-dimensional graphene layers,was prepared based on a developed drop-freeze-drying followed by carbonization approach.The nanofibrous carbon efficiently prevents the agglomeration of the graphene layers,which,in turn,reduces the shrinkage and maintains the structural stability of the hybrid carbon aerogel spheres.Consequently,the aerogel spheres showing an ultralow-density of 2.8 mg/cm^(3) and a porosity of 99.98%accomplish the tunable dielectric property and electromagnetic wave(EMW)absorption performance.The high-efficiency utilization of biomass-derived fibrous nanocarbon,graphene,the porous structure of the hybrid aerogel spheres leads to the excellent EMW absorption performance.The aerogel spheres display an effective absorption bandwidth of 6.16 GHz and a minimum reflection loss of−70.44 dB even at a filler loading of merely 3 wt.%,significantly outperforming that of other biomass-derived carbon-based EMW absorbing materials.This work offers a feasible,facile,scalable approach for fabricating high-performance and sustainable biomass-based aerogels,suggesting a tremendous application potential in EMW absorption and aerospace.

DNA methylation drives a new path in gastric cancer early detection:Current impact and prospects

Gastric cancer(GC)is one of the most common and deadly cancers worldwide.Early detection offers the best chance for curative treatment and reducing its mortality.However,the optimal population-based early screening for GC remains unmet.Aberrant DNA methylation occurs in the early stage of GC,exhibiting cancer-specific genetic and epigenetic changes,and can be detected in the media such as blood,gastric juice,and feces,constituting a valuable biomarker for cancer early detection.Furthermore,DNA methylation is a stable epigenetic alteration,and many innovative methods have been developed to quantify it rapidly and accurately.Nonetheless,large-scale clinical validation of DNA methylation serving as tumor biomarkers is still lacking,precluding their implementation in clinical practice.In conclusion,after a critical analysis of the recent existing literature,we summarized the evolving roles of DNA methylation during GC occurrence,expounded the newly discovered noninvasive DNA methylation biomarkers for early detection of GC,and discussed its challenges and prospects in clinical applications.

Research on Electromagnetic Wave Absorption Based on Electrospinning Technology

At present,in order to overcome electromagnetic interference and prevent electromagnetic harm,the research of new and efficient electromagnetic wave absorbing materials has become the research focus in the field of materials science.The one-dimensional structure can promote the impedance matching and attenuation characteristics of the absorbing materials.Electrospinning,as an effective method to prepare nanofibers with high length-diameter ratio,has been widely concerned because it is suitable for struc-tural design of various materials.In this paper,the research progress and absorption properties of nano-fiber materials prepared by electrospinning combined with different processes are introduced.