Gut microbiota modulation enhances the immune capacity of lizards under climate warming.

BACKGROUND: Host-microbial interactions are expected to affect species' adaptability to climate change but have rarely been explored in ectothermic animals. Some studies have shown that short-term warming reduced gut microbial diversity that could hamper host functional performance. RESULTS: However, our longitudinal experiments in semi-natural conditions demonstrated that warming decreased gut microbiota diversity at 2 months, but increased diversity at 13 and 27 months in a desert lizard (Eremias multiocellata). Simultaneously, long-term warming significantly increased the antibacterial activity of serum, immune responses (higher expression of intestinal immune-related genes), and the concentration of short-chain fatty acids (thereby intestinal barrier and immunity) in the lizard. Fecal microbiota transplant experiments further revealed that increased diversity of gut microbiota significantly enhanced antibacterial activity and the immune response of lizards. More specifically, the enhanced immunity is likely due to the higher relative abundance of Bacteroides in warming lizards, given that the bacteria of Bacteroides fragilis regulated IFN-ß expression to increase the immune response of lizards under a warming climate. CONCLUSIONS: Our study suggests that gut microbiota can help ectotherms cope with climate warming by enhancing host immune response, and highlights the importance of long-term studies on host-microbial interactions and their biological impacts.

Constructing magnetic/dielectric dual loss and phonon/electron thermal carriers γ-Al2O3-based yolk-shell microspheres to collaboratively advance microwave absorption and heat conduction.

The severe electromagnetic (EM) interference and overheating issues in 5G/6G electric devices increasingly heighten the need for developing multifunctional materials with large heat conduction (HC) and high EM wave (EMW) absorption. Here, a series of γ-Al2O3-based yolk-shell microspheres (γ-AlOOH, γ-Al2O3, γ-Al2O3@C, γ-Al2O3@Fe3O4@C, and γ-Al2O3@FeAl2O4@Fe@C YSMSs) as multifunctional fillers are investigated for the simultaneous improvement in the HC and EMW absorption of γ-Al2O3-based composites. Using γ-AlOOH YSMSs as precursors produced from a hydrothermal method, the γ-Al2O3-based YSMSs were synthesized via an annealing route or soaking-annealing route; their phases, textures, and compositions were finely adjusted by changing the Al3+/Fe3+ molar ratio (ß) and annealing temperature (Ta). Results show that the thermal transfers in the γ-Al2O3-based YSMSs are promoted by the synergic effect of phonons and electrons when they are utilized as thermally conductive fillers. Comparatively, the γ-Al2O3@FeAl2O4@Fe@C YSMSs formed at ß = 8 : 2 and Ta = 700 °C exhibit a high HC of 1.84-3.29 W m-1 K-1 in a loading amount of 5-40%, exceeding those of not merely γ-Al2O3, γ-AlOOH, γ-Al2O3@C, and γ-Al2O3@Fe3O4@C YSMSs but also most previously reported fillers. Furthermore, the γ-Al2O3@Fe3O4@C YSMSs exhibit prominent EMW absorption properties with a large ABW/d of 4.49 GHz mm-1 (just 30% loading), superior to most other Al2O3-based absorbers. Such excellent EMW absorption could be explained by magnetic/dielectric dual loss and significant cavity and interfacial effects caused by yolk-shell structures. In conclusion, this work inspires the development of yolk-shell structures with magnetic/dielectric dual loss and phonon/electron thermal carriers as high-performance bifunctional materials with exceptional heat conduction and EMW absorption.

Synchronously boosting microwave-absorbing and heat-conducting capabilities in CeO2/Ce(OH)3 core-shell nanorods/nanofibers via Fe-doping amount control.

To address the electromagnetic interference (EMI) and heat dissipation issues in electronics, we pioneered the synthesis of Fe-doped CeO2/Ce(OH)3 core-shell nanorods/nanofibers (CSNRs/NFs) through a simple one-pot hydrothermal reaction. The growth of core-shell nanofibers was driven by the minimal surface free energy and vacancy formation energy. By controlling the amount of Fe-doping, not simply Fe0 content, crystallite size, defects, impurities, and length/diameter ratios could be modulated, but the electric, magnetic, thermal, and microwave absorption performance. The efficient 3D network constructed by 1D nanofibers in a silicone matrix offered a continuous pathway for electrons/phonon relay transmission, endowing the composites with exceptional heating conductance (3.442 W m-1 K-1) at 20%Fe-doping. An ultrawide absorption band (9.26 GHz) with intense absorption (-42.33 dB) and small thickness (1.7 mm) was achieved at 10%Fe-doping due to excellent matching performance, strong attenuation ability, and large EM parameters. Overall, Fe-doped CeO2/Ce(OH)3 CSNFs are a promising material for next-generation electronics with effective heat dissipation and EM wave absorption due to their straightforward process, mass production, and outstanding comprehensive performance. Beyond providing a deeper insight into the accurate defect modulation in magnetic-dielectric-double-loss absorbents by doping, this paper proposes an electron/phonon relay transmission strategy to improve heat conductance.