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Epidermal skin sensors have emerged as a promising approach for continuous and noninvasive monitoring of vital health signals, but to maximize their performance, these sensors must integrate seamlessly with the skin, minimizing impedance while maintaining the skin's natural protective and regulatory functions.In this study, we introduce an imperceptible sweat sensor that achieves this seamless skin integration through interpenetrating networks formed by a porous, ultra-thin, ultra-high molecular weight polyethylene (UHMWPE) nanomembrane. Upon attachment to the skin by van der Waals force, the amphiphilic sweat extrudates infuse into the interconnected nanopores inside the hydrophobic UHWMPE nanomembrane, forming "pseudo skin" nanochannels for continuous sweat perspiration. This integration is further enhanced by the osmotic pressure generated during water evaporation. Leveraging the efficient transport of biomarkers through the "skin" channels within the porous membrane, we developed an organic electrochemical transducer (OECT) cortisol sensor via in-situ synthesis of a molecularly imprinted polymer (MIP) and poly(3,4 ethylenedioxythiophene) (PEDOT) within the nanomembrane. This demonstrates the capability to detect cortisol concentrations from 0.05 to 0.5 {\mu}M for seamless monitoring of stress levels. This work represents a significant advancement in self-adhesive sweat sensors that offer imperceptible and real-time non-invasive health monitoring capabilities.

It has been shown in recent works that JT gravity with matter with two boundaries has a type II$_\infty$ algebra on each side. As the bulk spacetime between the two boundaries fluctuates in quantum nature, we can only define the entanglement wedge for each side in a pure algebraic sense. As we take the semiclassical limit, we will have a fixed long wormhole spacetime for a generic partially entangled thermal state (PETS), which is prepared by inserting heavy operators on the Euclidean path integral. Under this limit, with appropriate assumptions of the matter theory, geometric notions of the causal wedge and entanglement wedge emerge in this background. In particular, the causal wedge is manifestly nested in the entanglement wedge. Different PETS are orthogonal to each other, and thus the Hilbert space has a direct sum structure over sub-Hilbert spaces labeled by different Euclidean geometries. The full algebra for both sides is decomposed accordingly. From the algebra viewpoint, the causal wedge is dual to an emergent type III$_1$ subalgebra, which is generated by boundary light operators. To reconstruct the entanglement wedge, we consider the modular flow in a generic PETS for each boundary. We show that the modular flow acts locally and is the boost transformation around the global RT surface in the semiclassical limit. It follows that we can extend the causal wedge algebra to a larger type III$_1$ algebra corresponding to the entanglement wedge. Within each sub-Hilbert space, the original type II$_\infty$ reduces to type III$_1$., Comment: 50 pages, 13 figures

The escalating global issue of plastic waste accumulation, specifically polyolefins, necessitates an urgent solution for upcycling these materials into beneficial compounds. Yet, achieving such upcycling without introducing carbon dioxide into the environment remains a formidable challenge. In this study, we demonstrate an eco-friendly approach for the photochemical conversion of ultrastrong, ultratransparent, and ultrathin polyethylene membrane into fibrous carbon nanomembrane at ambient conditions. The membrane was sputter-coated with platinum and cuprous oxide nanoparticles and exposed to simulated sunlight, resulting in a porous carbon membrane decorated with Pt nanoparticles. The new carbonized nanomembrane maintained the pristine membrane's morphology. The membrane exhibited high activity (2.11 mA/cm2) for electrochemical ethanol oxidation with stability over 1000 cycles. This work holds significance for sustainable plastic waste management and the design of new polyolefin materials in a circular economy.

In this work, we study a type of commuting SYK model in which all terms in the Hamiltonian are commutative to each other. Because of the commutativity, this model has a large number of conserved charges and is integrable. After the ensemble average of random couplings, we can solve this model exactly in any $N$. Though this integral model is not holographic, we do find that it has some holography-like features, especially the near-perfect size winding in high temperatures. Therefore, we would like to call it pseudo-holographic. We also find that the size winding of this model has a narrowly peaked size distribution, which is different from the ordinary SYK model. We apply the traversable wormhole teleportation protocol in the commuting SYK model and find that the teleportation has a few features similar to the semiclassical traversable wormhole but in different parameter regimes. We show that the underlying physics is not entirely determined by the size-winding mechanism but involves the peaked-size mechanism and thermalization. Lastly, we comment on the recent simulation of the dynamics of traversable wormholes on Google's quantum processor., Comment: 48 pages, 8 figures, 2 tables

We used a coarse-grained model to study the geometric and dynamic properties of flexible entangled polymer chains dissolved in explicit athermal solvents. Our simulations successfully reproduced the geometrical properties including the scaling relationships between mean-square end-to-end distance $$, chain entanglement lengths $N_{e}$ and concentration $\Phi$. Specifically, we find that $\sim N*\Phi^{-1/4}$,$N_{e} = 30.01\Phi^{-5/4}+31.23$. Dynamically, our model confirmed the ratio of the dynamic critical entanglement $N_{c}$ and the geometric entanglement length $N_{e}$ is constant, with $N_{c}/N_{e} = 5\sim 6$. To account for the local swelling effect for chains confined in athermal solvents, we treated the chains using the concept of blobs where each blob occupies a volume $\Omega_{b}$, with length $g$. Direct MD simulations and scaling analysis showed that $g \sim \Phi^{-25/36}$, $\Omega_{b}\sim\Phi^{-5/4}$. Using these together with the concentration dependent packing length $p \sim \Phi^{-5/12}$, we obtained a modified the Lin-Noolandi ansatz for concentrated flexible polymer chains in athermal solvents: $G \sim \frac{\Phi}{\left(N_{e} / g\right) \Omega_{b}} \sim \Phi^{-2.28}$. We demonstrate this modified ansatz agrees well with our coarse-grained numerical simulations., Comment: 9 pages, 10 figures

In non-maximally quantum chaotic systems, the exponential behavior of out-of-time-ordered correlators (OTOCs) results from summing over exchanges of an infinite tower of higher "spin" operators. We construct an effective field theory (EFT) to capture these exchanges in $(0+1)$ dimensions. The EFT generalizes the one for maximally chaotic systems, and reduces to it in the limit of maximal chaos. The theory predicts the general structure of OTOCs both at leading order in the $1/N$ expansion ($N$ is the number of degrees of freedom), and after resuming over an infinite number of higher order $1/N$ corrections. These general results agree with those previously explicitly obtained in specific models. We also show that the general structure of the EFT can be extracted from the large $q$ SYK model., Comment: 81 pages, 10 figures