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  1. The skin exhibits nonlinear mechanics, which is initially soft and stiffens rapidly as being stretched to prevent large deformation‐induced injuries. Developing skin‐interfaced bioelectronics with skin‐inspired nonlinear mechanical behavior, together with multiple other desired features (breathable, antibacterial, and sticky), is desirable yet challenging. Herein, this study reports the design, fabrication, and biomedical application of porous mesh bioelectronics that can simultaneously achieve these features. On the one hand, porous serpentine meshes of polyimide (PI) are designed and fabricated under the guidance of theoretical simulations to provide skin‐like nonlinear mechanics and high breathability. On the other hand, ultrasoft, sticky, and antibacterial polydimethylsiloxane (PDMS) is developed through epsilon polylysine (ε‐PL) modifications, which are currently lacking in the field. Here,ε‐PL‐modified PDMS is spray‐coated on PI meshes to form the core–shell structures without blocking their pores to offer ultrasoft, sticky, and antibacterial skin interfaces. And rationally designed porous hybrid meshes can not only retain skin‐like nonlinear mechanical properties but also enable the integration of both soft and hard bioelectronic components for various healthcare applications. As the exemplar example, this study integrates soft silver nanowires (AgNWs) based electrophysiological sensors and rigid commercial accelerometers on multifunctional porous meshes for concurrently monitoring heart electrical and mechanical functions to provide comprehensive information on the evolving heart status. 
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    Free, publicly-accessible full text available October 1, 2024
  2. Free, publicly-accessible full text available May 28, 2024
  3. Abstract We develop a nonequilibrium increment method in quantum Monte Carlo simulations to obtain the Rényi entanglement entropy of various quantum many-body systems with high efficiency and precision. To demonstrate its power, we show the results on a few important yet difficult (2 + 1) d quantum lattice models, ranging from the Heisenberg quantum antiferromagnet with spontaneous symmetry breaking, the quantum critical point with O(3) conformal field theory (CFT) to the toric code $${{\mathbb{Z}}}_{2}$$ Z 2 topological ordered state and the Kagome $${{\mathbb{Z}}}_{2}$$ Z 2 quantum spin liquid model with frustration and multi-spin interactions. In all these cases, our method either reveals the precise CFT data from the logarithmic correction or extracts the quantum dimension in topological order, from the dominant area law in finite-size scaling, with very large system sizes, controlled errorbars, and minimal computational costs. Our method, therefore, establishes a controlled and practical computation paradigm to obtain the difficult yet important universal properties in highly entangled quantum matter. 
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  4. We propose a new mechanism to augment a word vector embedding representation that offers improved bias removal while retaining the key information—resulting in improved interpretability of the representation. Rather than removing the information associated with a concept that may induce bias, our proposed method identifies two concept subspaces and makes them orthogonal. The resulting representation has these two concepts uncorrelated. Moreover, because they are orthogonal, one can simply apply a rotation on the basis of the representation so that the resulting subspace corresponds with coordinates. This explicit encoding of concepts to coordinates works because they have been made fully orthogonal, which previous approaches do not achieve. Furthermore, we show that this can be extended to multiple subspaces. As a result, one can choose a subset of concepts to be represented transparently and explicitly, while the others are retained in the mixed but extremely expressive format of the representation. 
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  5. This study aimed to explore lignin as a naturally occurring aromatic precursor for the synthesis of LIG and further fabrication of ultrasensitive strain sensors for the detection of small deformations. One-step direct laser writing (DLW) induced high quality porous graphene, so called laser induced graphene (LIG), from kraft lignin under the conditions optimized for laser power, focus distance, and lignin loading. An electrode based on the resulting LIG was facilely fabricated by transferring LIG onto an elastomeric substrate ( i.e. , Dragon Skin™). The novel LIG transfer was facilitated by spin coating followed by water lifting, leading to the full retention of porous graphene onto the elastomeric substrate. The strain sensor was shown to be highly sensitive to small human body motions and tiny deformations caused by vibrations. It had a working range of up to 14% strain with a gauge factor of 960 and showed high stability as evidenced by repetitive signals over 10 000 cycles at 4% strain. The sensor was also successfully demonstrated for detecting human speaking, breath, seismocardiography (SCG), and movement of pulse and eye. Overall, the lignin-derived LIG can serve as excellent piezoresistive materials for wearable, stretchable, and ultrasensitive strain sensors with applications in human body motion monitoring and sound-related applications. 
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