A PAR6–aPKC–LGL structure reveals how LGL antagonizes aPKC
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Memristors based on two-dimensional h-BN materials: synthesis, mechanism, optimization and application
Memristors offer vast application opportunities in storage, logic devices, and computation due to their nonvolatility, low power consumption, and fast operational speeds. Two-dimensional materials, characterized by their novel mechanisms, ultra-thin channels, high mechanical flexibility, and superior electrical properties, demonstrate immense potential in the domain of high-density, fast, and energy-efficient memristors. Hexagonal boron nitride (h-BN), as a new two-dimensional material, has the characteristics of high thermal conductivity, flexibility, and low power consumption, and has a significant application prospect in the field of memristor. In this paper, the recent research progress of the h-BN memristor is reviewed from the aspects of device fabrication, resistance mechanism, and application prospect.
T-cell receptor structures and predictive models reveal comparable alpha and beta chain structural diversity despite differing genetic complexity
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Dact1 induces Dishevelled oligomerization to facilitate binding partner switch and signalosome formation during convergent extension
Convergent extension (CE) is a universal morphogenetic engine that promotes polarized tissue extension. In vertebrates, CE is regulated by non-canonical Wnt ligands signaling through “core” proteins of the planar cell polarity (PCP) pathway, including the cytoplasmic protein Dishevelled (Dvl), receptor Frizzled (Fz) and tetraspan protein Van gogh-like (Vangl). PCP was discovered in Drosophila to coordinate polarity in the plane of static epithelium, but does not regulate CE in flies. Existing evidence suggests that adopting PCP for CE might be a vertebrate-specific adaptation with incorporation of new regulators. Herein we use Xenopus to investigate Dact1, a chordate-specific protein. Dact1 induces Dvl to form oligomers that dissociate from Vangl, but stay attached with Fz as signalosome-like clusters and co-aggregate with Fz into protein patches upon non-canonical Wnt induction. Functionally, Dact1 antagonizes Vangl, and synergizes with wild-type Dvl but not its oligomerization-defective mutants. We propose that, by promoting Dvl oligomerization, Dact1 couples Dvl binding partner switch with signalosome-like cluster formation to initiate non-canonical Wnt signaling during vertebrate CE.
Human-structure and human-structure-human interaction in electro-quasistatic regime
Augmented living equipped with electronic devices requires widespread connectivity and a low-loss communication medium for humans to interact with ambient technologies. However, traditional radiative radio frequency-based communications require wireless pairing to ensure specificity during information exchange, and with their broadcasting nature, these incur energy absorption from the surroundings. Recent advancements in electroquasistatic body-coupled communication have shown great promise by utilizing conductive objects like the human body as a communication medium. Here we propose a fundamental set of modalities of non-radiative interaction by guiding electroquasistatic signals through conductive structures between humans and surrounding electronic devices. Our approach offers pairing-free communication specificity and lower path loss during touch. Here, we propose two modalities: Human-Structure Interaction and Human-Structure Human Interaction with wearable devices. We validate our theoretical understanding with numerical electromagnetic simulations and experiments to show the feasibility of the proposed approach. A demonstration of the real-time transfer of an audio signal employing an human body communications-based Human-Structure Interaction link is presented to highlight the practical impact of this work. The proposed techniques can potentially influence Human-Machine Interaction research, including the development of assistive technology for augmented living and personalized healthcare.
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