Structural Evolution Design and Optimization for the Metamaterials with Broadband Frequency-Independent Negative Permeability

Plasmonics - Broadband frequency-independent operations are strongly desired in metamaterial applications. In this work, we unveil the roles of each element acting in the metamaterial unit with a...     

On the Reversibility and Fragility of Sodium Metal Electrodes

Metallic sodium is receiving renewed interest as a battery anode material because the metal is earth‐abundant, inexpensive, and offers a high specific storage capacity (1166 mAh g^?1 at ?2.71 V vs the standard hydrogen potential). Unlike metallic lithium, the case for Na as the anode in rechargeable batteries has already been demonstrated on a commercial scale in high‐temperature Na||S and Na||NiCl₂ secondary batteries, which increases interest. The reversibility of room temperature sodium anodes is investigated in galvanostatic plating/stripping reactions using in situ optical visualization and galvanostatic polarization measurements. It is discovered that electronic disconnection of mossy metallic Na deposits (“orphaning”) is a dominant source of anode irreversibility in liquid electrolytes. The disconnection is shown by means of direct visualization studies to be triggered by a root‐breakage process during the stripping cycle. As a further step toward electrode designs that are able to accommodate the fragile Na deposits, electrodeposition of Na is demonstrated in nonplanar electrode architectures, which provide continuous and morphology agnostic access to the metal at all stages of electrochemical cycling. On this basis, nonplanar Na electrodes are reported, which exhibit exceptionally high levels of reversibility (Coulombic efficiency >99.6% for 1 mAh cm^?2 Na throughput) in room‐temperature, liquid electrolytes.     

Facile Patterning of Laser‐Induced Graphene with Tailored Li Nucleation Kinetics for Stable Lithium‐Metal Batteries

A facile and scalable approach is reported to stabilize the lithium‐metal anode by regulating the Li nucleation and deposition kinetics with laser‐induced graphene (LIG). By processing polyimide (PI) films on copper foils with a laser, a 3D‐hierarchical composite material is constructed, consisting of a highly conductive copper substrate, a pillared array of flexible PI, and most importantly, porous LIG on the walls of the PI pillars. The high number of defects and heteroatoms present in LIG significantly lowers the Li nucleation barrier compared to the copper foil. An overpotential‐free Li nucleation process is identified at current densities lower than 0.2 mA cm^?2. Theoretical computations reveal that the defects serve as nucleation centers during the heterogeneous nucleation of lithium. By adopting such composites, ultrastable lithium‐metal anodes are obtained with high Coulombic efficiencies of ≈99%. Full lithium‐metal cells based on LiFePO₄ cathodes with a material loading of ≈15 mg cm^?2 and a negative/positive ratio of 5/1 could be cycled over 250 times with a capacity loss of less than 10%. The current work highlights the importance of nucleation kinetics on the stability of metallic anodes and demonstrates a practical method toward long lasting Li‐metal batteries.     

Real microgravity condition promoted regeneration capacity of induced pluripotent stem cells during the TZ‐1 space mission

Induced pluripotent stem cells (iPSCs) are reprogrammed somatic cells that gained self‐renewal and differentiation capacity similar to embryonic stem cells. Taking the precious opportunity of the TianZhou‐1 spacecraft mission, we studied the effect of space microgravity (µg) on the self‐renewal capacity of iPSCs. Murine iPSCs carrying pluripotency reporter Oct4‐GFP were used. The Oct4‐EGFP‐iPSCs clones were loaded into the bioreactor and exposed to μg in outer space for 14 days. The control experiment was performed in identical device but on the ground in earth gravity (1 g). iPSCs clones were compact and highly expressed Oct4 before launch. In μg condition, cells in iPSC clones spread out more rapidly than those in ground 1 g condition during the first 3 days after launch. However, in 1 g condition, as the cell density increases, the Oct4‐GFP signal dropped significantly during the following 3 days. Interestingly, in μg condition, iPSCs originated from the spread‐out clones during the first 3 days appeared to cluster together and reform colonies that activated strong Oct4 expression. On the other hand, iPSC clones in 1 g condition were not able to recover Oct4 expression after overgrown. Our study for the first time performed real‐time imaging on the proliferation process of iPSCs in space and found that in μg condition, cell behaviour appeared to be more dynamic than on the ground.     

Identification,design and synthesis of novel pyrazolopyridine influenza virus nonstructural protein 1 antagonists

Nonstructural protein 1 (NS1) plays a crucial function in the replication, spread, and pathogenesis of influenza virus by inhibiting the host innate immune response. Here we report the discovery and optimization of novel pyrazolopyridine NS1 antagonists that can potently inhibit influenza A/PR/8/34 replication in MDCK cells, rescue MDCK cells from cytopathic effects of seasonal influenza A strains, reverse NS1-dependent inhibition of IFN-β gene expression, and suppress the slow growth phenotype in NS1-expressing yeast. These pyrazolopyridines will enable researchers to investigate NS1 function during infection and how antagonists can be utilized in the next generation of treatments for influenza infection.     

Emerging roles of long non‐coding RNAs in neuropathic pain

Neuropathic pain, a type of chronic and potentially disabling pain resulting from primary injury/dysfunction of the somatosensory nervous system and spinal cord injury, is one of the most intense types of chronic pain, which incurs a significant economic and public health burden. However, our understanding of its cellular and molecular pathogenesis is still far from complete. Long non‐coding RNAs (lncRNAs) are important regulators of gene expression and have recently been characterized as key modulators of neuronal functions. Emerging evidence suggested that lncRNAs are deregulated and play pivotal roles in the development of neuropathic pain. This review summarizes the current knowledge about the roles of deregulated lncRNAs (eg, KCNA2‐AS, uc.48+, NONRATT021972, MRAK009713, XIST, CCAT1) in the development of neuropathic pain. These studies suggested that specific regulation of lncRNAs or their downstream targets might provide novel therapeutic avenues for this refractory disease.