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Improving the absorption of electromagnetic waves at low-frequency bands (2-8 GHz) is crucial for the increasing electromagnetic (EM) pollution brought about by the innovation of the fifth generation (5G) communication technology. However, the poor impedance matching and intrinsic attenuation of material in low-frequency bands hinders the development of low-frequency electromagnetic wave absorbing (EMWA) materials. Here we propose an interface-induced dual-pinning mechanism and establish a magnetoelectric bias interface by constructing bilayer core-shell structures of NiFe 2 O 4 (NFO)@BiFeO 3 (BFO)@polypyrrole (PPy). Such heterogeneous interface could induce distinct magnetic pinning of the magnetic moment in the ferromagnetic NFO and dielectric pinning of the dipole rotation in PPy. The establishment of the dual-pinning effect resulted in optimized impedance and enhanced attenuation at low-frequency bands, leading to better EMWA performance. The minimum reflection loss (RL min ) at thickness of 4.43 mm reaches -65.30 dB (the optimal absorption efficiency of 99.99997%), and the effective absorption bandwidth (EAB) can almost cover C-band (4.72 ~ 7.04 GHz) with low filling of 15.0 wt.%. This work proposes a mechanism to optimize low-frequency impedance matching with electromagnetic wave (EMW) loss and pave an avenue for the research of high-performance low-frequency absorbers. This paper proposes a dual-pinning mechanism induced by a magneto-electric bias interface and uses it to designs a double-layer core-shell structure, demonstrating that the mechanism improves electromagnetic wave absorption in the low-frequency bands.

HighlightsUltralight 3D NiCo compound@MXene nanocomposites that inherited hollow polyhedral skeleton and excellent conductive network were fabricated.Excellent electromagnetic absorption performance was achieved with optimal RLmin value of − 67.22 dB and ultra-wide EAB of 6.72 GHz under the low filler loading.Electromagnetic parameters and microwave absorption property can be distinctly or slightly regulated by adjusting the filler loading and decoration of Ti3C2Tx nanoflakes.The 3D hollow hierarchical architectures tend to be designed for inhibiting stack of MXene flakes to obtain satisfactory lightweight, high-efficient and broadband absorbers. Herein, the hollow NiCo compound@MXene networks were prepared by etching the ZIF 67 template and subsequently anchoring the Ti3C2Tx nanosheets through electrostatic self-assembly. The electromagnetic parameters and microwave absorption property can be distinctly or slightly regulated by adjusting the filler loading and decoration of Ti3C2Tx nanoflakes. Based on the synergistic effects of multi-components and special well-constructed structure, NiCo layered double hydroxides@Ti3C2Tx (LDHT-9) absorber remarkably achieves unexpected effective absorption bandwidth (EAB) of 6.72 GHz with a thickness of 2.10 mm, covering the entire Ku-band. After calcination, transition metal oxide@Ti3C2Tx (TMOT-21) absorber near the percolation threshold possesses minimum reflection loss (RLmin) value of − 67.22 dB at 1.70 mm within a filler loading of only 5 wt%. This work enlightens a simple strategy for constructing MXene-based composites to achieve high-efficient microwave absorbents with lightweight and tunable EAB.

In the natural environment, interactions between species are a common natural phenomena. The mechanisms of interaction between different species are mainly studied using genomic, transcriptomic, proteomic, and metabolomic techniques. Metabolomics is a crucial part of system biology and is based on precision instrument analysis. In the last decade, the emerging field of metabolomics has received extensive attention. Metabolomics not only provides a qualitative and quantitative method for studying the mechanisms of interactions between different species, but also helps clarify the mechanisms of defense between the host and pathogen, and to explore new metabolites with various biological activities. This review focuses on the methods and progress of interspecies metabolomics. Additionally, the prospects and challenges of interspecies metabolomics are discussed.

With rapid advancements in remote sensing image registration algorithms, comprehensive imaging applications are no longer limited to single-modal remote sensing images. Instead, multi-modal remote sensing (MMRS) image registration has become a research focus in recent years. However, considering multi-source, multi-temporal, and multi-spectrum input introduces significant nonlinear radiation differences in MMRS images for which researchers need to develop novel solutions. At present, comprehensive reviews and analyses of MMRS image registration methods are inadequate in related fields. Thus, this paper introduces three theoretical frameworks: namely, area-based, feature-based and deep learning-based methods. We present a brief review of traditional methods and focus on more advanced methods for MMRS image registration proposed in recent years. Our review or comprehensive analysis is intended to provide researchers in related fields with advanced understanding to achieve further breakthroughs and innovations.

Rainfall intensity and duration pose significant challenges to the stability of plantations in mountainous areas prone to soil erosion. Accurately understanding how tree transpiration responds to atmospheric evaporation demands under real-time rainfall conditions is essential for enhancing our understanding of tree water use. Since 2015, the alder-cypress forest has been completely replaced by a pure cypress forest, which led us to employ the heat dissipation probe method to measure sap flux of cypress wood. To analyze the responses of cypress trees to real-time and delay-time rainfall, we utilized no- and seasonal autoregressive integrated moving average with exogenous variables models to analyze the responses of sap flux to external environmental factors. Our analysis revealed that past values of sap flux and vapor pressure deficit jointly accounted for 79.6% (wet season) and 34.6% (dry season) of current sap flux values in the delay-time condition. However, under a real-time condition, past sap flux values and rainfall did not explain the variance in current sap flux values (R 2  = 7.01 × 10 − 4 ). This indicates a decoupling between present and past sap flux and the other three environmental factors in real-time conditions. The findings demonstrate significantly different hydraulic drive patterns of trees under real-time rainfall conditions, providing a new basis for forest managers to optimize irrigation plans and allocate water resources effectively.

Temperature is a key factor for determining the lifespan of both poikilotherms and homeotherms. It is believed that animals live longer at lower body temperatures. However, the precise mechanism remains largely unknown. Here, we report that autophagy serves as a boost mechanism for longevity at low temperature in the nematode Caenorhabditis elegans . The adiponectin receptor AdipoR2 homolog PAQR-2 signaling detects temperature drop and augments the biosynthesis of two ω-6 polyunsaturated fatty acids, γ-linolenic acid and arachidonic acid. These two polyunsaturated fatty acids in turn initiate autophagy in the epidermis, delaying an age-dependent decline in collagen contents, and extending the lifespan. Our findings reveal that the adiponectin receptor PAQR-2 signaling acts as a regulator linking low temperature with autophagy to extend lifespan, and suggest that such a mechanism may be evolutionally conserved among diverse organisms. Decreased temperatures lengthen C. elegans lifespan by mechanisms that are not fully understood. Here the authors show that autophagy activation contributes to lifespan extension at low temperatures and that this involves adiponectin receptor PAQR-2 signaling.

Quercetin (QR) has significant anti-respiratory syncytial virus (RSV) effects. However, its therapeutic mechanism has not been thoroughly explored. In this study, a lung inflammatory injury model caused by RSV was established in mice. Untargeted lung tissue metabolomics was used to identify differential metabolites and metabolic pathways. Network pharmacology was used to predict potential therapeutic targets of QR and analyze biological functions and pathways modulated by QR. By overlapping the results of the metabolomics and the network pharmacology analyses, the common targets of QR that were likely to be involved in the amelioration of RSV-induced lung inflammatory injury by QR were identified. Metabolomics analysis identified 52 differential metabolites and 244 corresponding targets, while network pharmacology analysis identified 126 potential targets of QR. By intersecting these 244 targets with the 126 targets, hypoxanthine–guanine phosphoribosyltransferase (HPRT1), thymidine phosphorylase (TYMP), lactoperoxidase (LPO), myeloperoxidase (MPO), and cytochrome P450 19A1 (CYP19A1) were identified as the common targets. The key targets, HPRT1, TYMP, LPO, and MPO, were components of purine metabolic pathways. The present study demonstrated that QR effectively ameliorated RSV-induced lung inflammatory injury in the established mouse model. Combining metabolomics and network pharmacology showed that the anti-RSV effect of QR was closely associated with purine metabolism pathways.

Despite the many advantages of tube systems with braces, known as trussed tubes, no specific seismic design criteria exist in the current regulations to design them, and practitioners utilize common methods used for common building structures to deal with designing such systems. The aim of this study is to investigate the performance of a 31-story steel trussed-tube building designed according to the customary design provisions. To evaluate the performance of the code-conforming designed structure, a three-dimensional nonlinear static (pushover) analysis is employed, and the acceptance criteria corresponding to different performance levels are examined. The obtained performance-based results are then compared with the design based on the customary guidelines, and the shortcomings of common design regulations in the design of trussed-tube buildings are highlighted. By observing the state of the plastic hinges, as well as force-controlled joints at two distinct earthquake hazard levels, it is found that the structure under study, which was loaded, analyzed, and designed exactly in compliance with the requirements of the regulations and standards, does not satisfy the performance criteria. In a typical nonlinear brace hinge, for instance, the results indicate that the LS acceptance criterion has been exceeded by approximately 30 percent at the BSE-1 hazard level. Also, the drifts surpass the 1% limit at specific levels, with the maximum drift reaching approximately 1.4%. As a result, the design of trussed-tube systems based on common codes and regulations can lead to an unsafe design that lacks the expected performance intended in their service life.

Carbon aerogels demonstrate wide applications for their ultralow density, rich porosity, and multifunctionalities. Their compressive elasticity has been achieved by different carbons. However, reversibly high stretchability of neat carbon aerogels is still a great challenge owing to their extremely dilute brittle interconnections and poorly ductile cells. Here we report highly stretchable neat carbon aerogels with a retractable 200% elongation through hierarchical synergistic assembly. The hierarchical buckled structures and synergistic reinforcement between graphene and carbon nanotubes enable a temperature-invariable, recoverable stretching elasticity with small energy dissipation (~0.1, 100% strain) and high fatigue resistance more than 10 6 cycles. The ultralight carbon aerogels with both stretchability and compressibility were designed as strain sensors for logic identification of sophisticated shape conversions. Our methodology paves the way to highly stretchable carbon and neat inorganic materials with extensive applications in aerospace, smart robots, and wearable devices. Improved compressive elasticity was lately demonstrated for carbon aerogels but the problem of reversible stretchability remained a challenge. Here the authors use a hierarchical structure design and synergistic effects between carbon nanotubes and graphene to achieve high stretchability in carbon aerogels.

This study was to investigate the effects of Tai Chi (TC) and whole-body vibration (WBV) exercise in sarcopenic men in advanced old age. Ninety sarcopenic men (mean age 88.6 years; age range 85–101 years) were divided into three groups: TC group, WBV group, and control (CON) group. Patients in the two treatment groups received 8 weeks of training in either TC or WBV, while the control group received reminders not to change their level of physical exercise or lifestyle. Patients in all groups also received health information related to sarcopenia. Muscle mass, muscle strength, and physical performance [balance, gait speed, timed-up-and-go test (TUGT), and five-times-sit-to-stand test (FTSST)] were analyzed and compared among the three groups. Finally, seventy-nine subjects completed the study (TC n  = 24; WBV n  = 28; and CON 27). Muscle strength was significantly increased in the TC and WBV groups compared to the control group ( P  < 0.01). Following 8 weeks of exercise, improvements were observed in all physical performance tests for the TC and WBV groups ( P  < 0.05). The improvement in balance was greater in the TC group than the WBV group. Time × Group effects revealed significant improvements in muscle strength in the lower extremities ( P  < 0.05) and physical performance ( P  < 0.01) in both the TC and WBV groups. Changes in muscle mass, as measured by dual-energy X-ray absorptiometry, did not significantly differ between groups. These findings indicate that TC and WBV are effective treatments for improving muscle strength and physical performance in sarcopenic men in advanced old age.