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Due to their almost unlimited scalability, redox flow batteries can make versatile and affordable energy storage systems. Redox active materials (redoxmers) in these batteries largely define their electrochemical performance, including the life span of the battery that depends on the stability of charged redoxmers. In this study, we examine the effects of expanding the π-system in the arene rings on the chemical stability of dialkoxyarene redoxmers that are used to store positive charge in RFBs. When 1,4-dimethoxybenzene is π-extended to 1,4-dimethoxynaphthalene, a lower redox potential, improved kinetic stability, and longer cycling life are observed. However, when an additional ring is fused to make 9,10-dimethoxyanthracene, the radical cation undergoes rapid O-dealkylation possibly due to increased steric strain that drives methoxy out of the arene plane thus breaking the π-conjugation with O 2p orbitals. On the other hand, the planar structure of 1,4-dimethoxynaphthalene may facilitate second-order reactions of radical cations leading to their neutralization in the bulk. Our study suggests that extending the π-system changes reactivity in multiple (sometimes, opposite) ways, so lowering the oxidation potential through π-conjugation to improve redoxmer stability should be pursued with caution. 

Realization of ferromagnetic (FM) interlayer coupling in magnetic topological insulators (TIs) of the MnBi 2 Te 4 family of materials (MBTs) may pave the way for realizing the high-temperature quantum anomalous Hall effect (high- T QAHE). Here we propose a generic dual d-band (DDB) model to elucidate the energy difference (Δ E = E AFM − E FM ) between the AFM and FM coupling in transition-metal (TM)-doped MBTs, where the valence of TMs splits into d-t 2g and d-e g sub-bands. Remarkably, the DDB shows that Δ E is universally determined by the relative position of the dopant (X) and Mn d-e g / t 2g bands, . If Δ E d > 0, then Δ E > 0 and the desired FM coupling is favored. This surprisingly simple rule is confirmed by first-principles calculations of hole-type 3d and 4d TM dopants. Significantly, by applying the DDB model, we predict the high- T QAHE in the V-doped Mn 2 Bi 2 Te 5 , where the Curie temperature is enhanced by doubling of the MnTe layer, while the topological order mitigated by doping can be restored by strain. 

To sensitively detect multiple and cross-species disease-related targets from a single biological sample in a quick and reliable manner is of high importance in accurately diagnosing and monitoring diseases. Herein, a surface-enhanced Raman scattering (SERS) sensor based on a functionalized multiple-armed tetrahedral DNA nanostructure (FMTDN) immobilized silver nanorod (AgNR) array substrate and Au nanoparticle (AuNP) SERS tags is constructed to achieve both multiplex detection and enhanced sensitivity using a sandwich strategy. The sensor can achieve single, dual, and triple biomarker detections of three lung cancer-related nucleic acid and protein biomarkers, i.e. , miRNA-21, miRNA-486 and carcinoembryonic antigen (CEA) in human serum. The enhanced SERS signals in multiplex detections are due to the DNA self-assembled AuNP clusters on the silver nanorod array during the assay, and the experimentally obtained relative enhancement factor ratios, 150 for AuNP dimers and 840 for AuNP trimers, qualitatively agree with the numerically calculated local electric field enhancements. The proposed FMTDN-functionalized AgNR SERS sensor is capable of multiplex and cross-species detection of nucleic acid and protein biomarkers with improved sensitivity, which has great potential for the screening and clinical diagnosis of cancer in the early stage. 

Dynein harnesses ATP hydrolysis to move cargo on microtubules in multiple biological contexts. Dynein meets a unique challenge in meiosis by moving chromosomes tethered to the nuclear envelope to facilitate homolog pairing essential for gametogenesis. Though processive dynein motility requires binding to an activating adaptor, the identity of the activating adaptor required for dynein to move meiotic chromosomes is unknown. We show that the meiosis-specific nuclear-envelope protein KASH5 is a dynein activating adaptor: KASH5 directly binds dynein using a mechanism conserved among activating adaptors and converts dynein into a processive motor. We map the dynein-binding surface of KASH5, identifying mutations that abrogate dynein binding in vitro and disrupt recruitment of the dynein machinery to the nuclear envelope in cultured cells and mouse spermatocytes in vivo. Our study identifies KASH5 as the first transmembrane dynein activating adaptor and provides molecular insights into how it activates dynein during meiosis. 

Cybersickness in Virtual Reality (VR) is a serious issue affecting the overall experience. Many research papers have investigated the causes of cybersickness and offered potential solutions for reducing cybersickness. In this paper, we demonstrate a method to reduce cybersickness by using a novel rendering technique in the virtual environment (VE)- Dynamic Mono-Stereoscopic Rendering System (DMSRS). The DMSRS system uses two different cameras to create a hybrid rendering that includes monoscopic and stereoscopic systems. By default, VEs are rendered using stereoscopic or monoscopic rendering exclusively. The results indicate that cybersickness decreased amongst users with little to no VR experience hindered when using the DMSRS.