Symbolic regression (SR), exploring mathematical expressions from a given data set to construct an interpretable model, emerges as a powerful computational technique with the potential to transform the “black box” machining learning methods into physical and chemistry interpretable expressions in material science research. In this review, the current advancements in SR are investigated, focusing on the underlying theories, fundamental flowcharts, various techniques, implemented codes, and application fields. More predominantly, the challenging issues and future opportunities in SR that should be overcome to unlock the full potential of SR in material design and research, including graphics processing unit acceleration and transfer learning algorithms, the trade-off between expression accuracy and complexity, physical or chemistry interpretable SR with generative large language models, and multimodal SR methods, are discussed.
The functional concept of using synthetic entities to supplement or replace certain functions or structures of biological cells is realized by the development of atypical artificial cells using a bottom-up approach. Tremendous progress has been achieved over the past 5 years that focuses on the therapeutic applications of atypical artificial cells, especially in the anticancer arena. Artificial cell-based anticancer strategies have demonstrated eminent advantages over conventional anticancer tactics, with excellent biocompatibility and targeting capability. The present review commences with introducing the constructing principles and classification of artificial cells. Artificial cell-based applications in cancer prophylaxis, diagnosis, and treatment are subsequently highlighted. These stimulating outcomes may inspire the development of next-generation anticancer therapeutic strategies.
Poly(vinylidene fluoride) (PVDF) is the most attractive piezoelectric polymerfor application in flexible sensors. To attain excellent piezoelectric properties,a substantial amount of spontaneous polar β-phase content is highly desired.Nevertheless, the current reported manufacturing methods to increase β-phasecontents are inconvenient and complex, hindering progress in PVDF’sapplication. This work proposes a folding-hot-pressing method to fabricatehigh β-phase-content PVDF films. Structural characterization indicates thatthe films have α and β phases and the folding-hot-pressing process transformsthe α phase into the β phase. Due to the 97.5% β-phase content and alignedstructure, a piezoelectric constant of 20 pC/N is achieved in the three-timesfolded film. Furthermore, the process method enhances the tensile strength(126.2 MPa) of the films, with a low Young’s modulus (0.87 GPa) remaining,making the films applicable for flexible piezoelectric sensors. Additionally,sensors based on the achieved films were assembled and applied for humanphysiological activity monitoring. This work offers a scalable new meltprocessingstrategy for developing high-performance PVDF-based piezoelectriccomposite films for wearable electronic devices.
The shuttle effect of lithium polysulfides (LiPSs) and their sluggish kinetic processes lead to rapid capacity fading and poor cycling stability in lithium–sulfur (Li–S) batteries, limiting their commercial viability. This study proposes a functionalized separator with adsorption and synergistic catalysis ability for Li–S batteries. The modified separator comprises Ti3C2Tx sheets, CoO, and MoO3. Experimental and theoretical calculations demonstrate that Ti3C2Tx/CoO/MoO3 composite not only effectively inhibits the shuttle effect of LiPSs, ensuring efficient utilization of active materials, but also enhances reversibility and reaction kinetics among LiPSs. The full exposure of active sites in the Ti3C2Tx/CoO/MoO3 composite and the synergistic action of different catalysts enable efficient capture and conversion of LiPSs molecules at the material surface. Besides, the lithium–sulfur batteries with Ti3C2Tx/CoO/MoO3@PP separator exhibited only a 0.042% capacity decay per cycle at 0.5 C (800 cycles). Moreover, a high areal capacity of 6.85mAh cm-2 was achieved at high sulfur loading (7.9mg cm-2) and low electrolyte-to-sulfur ratio (10 µLmg-1).
Due to tissue lineage variances and the anisotropic physiological characteristics, regenerating complex osteochondral tissues (cartilage and subchondral bone) remains a great challenge, which is primarily due to the distinct requirements for cartilage and subchondral bone regeneration. For cartilage regeneration, a significant amount of newly generated chondrocytes is required while maintaining their phenotype. Conversely, bone regeneration necessitates inducing stem cells to differentiate into osteoblasts. Additionally, the construction of the osteochondral interface is crucial. In this study, we fabricated a biphasic multicellular bioprinted scaffold mimicking natural osteochondral tissue employing three-dimensional (3D) bioprinting technology. Briefly, gelatin-methacryloyl (GelMA) loaded with articular chondrocytes and bone marrow mesenchymal stem cells (ACs/BMSCs), serving as the cartilage layer, preserved the phenotype of ACs and promoted the differentiation of BMSCs into chondrocytes through the interaction between ACs and BMSCs, thereby facilitating cartilage regeneration. GelMA/strontiumsubstituted xonotlite (Sr-CSH) loaded with BMSCs, serving as the subchondral bone layer, regulated the differentiation of BMSCs into osteoblasts and enhanced the secretion of cartilage matrix by ACs in the cartilage layer through the slow release of bioactive ions from Sr-CSH. Additionally, GelMA, serving as the matrix material, contributed to the reconstruction of the osteochondral interface. Ultimately, this biphasic multicellular bioprinted scaffold demonstrated satisfactory simultaneous regeneration of osteochondral defects. In this study, a promising strategy for the application of 3D bioprinting technology in complex tissue regeneration was proposed.
Our feet are often subjected to moist and warm environments, which can promote the growth of harmful bacteria and the development of severe infection in wounds located in the foot. As a result, there is a need for new and innovative strategies to safely sterilize feet, when shoes are worn, to prevent any potential foot-related diseases. In this paper, we have produced a nondestructive, biocompatible and convenient-to-use insole by embedding a BaTiO3 (BT) ferroelectric material into a conventional polydimethylsilane (PDMS) insole material to exploit a ferroelectric catalytic effect to promote the antibacterial and healing of infected wounds via the ferroelectric charges generated during walking. The formation of reactive oxygen species generated through a ferroelectric catalytic effect in the PDMS-BT composite is shown to increase the oxidative stress on bacteria and decrease both the activity of bacteria and the rate of formation of bacterial biofilms. In addition, the ferroelectric field generated by the PDMS-BT insole can enhance the level of transforming growth factor-beta and CD31 by influencing the endogenous electric field of a wound, thereby promoting the proliferation, differentiation of fibroblasts and angiogenesis. This work therefore provides a new route for antimicrobial and tissue reconstruction by integrating a ferroelectric biomaterial into a shoe insole, with significant potential for health-related applications.
Long-term biopotential monitoring requires high-performance biocompatible wearable dry electrodes. But currently, it is challenging to establish a form-preserving fit with the skin, resulting in high interface impedance and motion artifacts. This research aims to present an innovative solution using an all-green organic dry electrode that eliminates the aforementioned challenges. The dry electrode is prepared by introducing biocompatible maltitol into the chosen conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). Thanks to the secondary doping and plasticizer effect of maltitol, the dry electrode exhibits good stretchability (62%), strong self-adhesion (0.46N/cm), high conductivity (102 S/cm), and low Young’s modulus (7 MPa). It can always form a conformal contact with the skin even during body movements. Together with good electrical properties, the electrode enables a lower skin contact impedance compared to the current standard Ag/AgCl gel electrode. Consequently, the application of this dry electrode in bioelectrical signal measurement (electromyography, electrocardiography, electroencephalography) and long-term biopotential monitoring was successfully demonstrated.
Lithium (Li)-metal batteries with polymer electrolytes are promising for highenergy-density and safe energy storage applications. However, current polymer electrolytes suffer either low ionic conductivity or inadequate ability to suppress Li dendrite growth at high current densities. This study addresses both issues by incorporating two-dimensional oxygenated carbon nitride (2D OCN) into a polyvinylidene fluoride (PVDF)-based composite polymer electrolyte and modifying the Li anode with OCN. The OCN nanosheets incorporated PVDF electrolyte exhibits a high ionic conductivity (1.6 × 10-4 S cm-1 at 25°C) and Li+ transference number (0.62), wide electrochemical window (5.3), and excellent fire resistance. Furthermore, the OCN-modified Li anode in situ generates a protective layer of Li3N during cycling, preventing undesirable reactions with PVDF electrolyte and effectively suppressing Li dendrite growth. Symmetric cells using the upgraded PVDF polymer electrolyte and modified Li anode demonstrate long cycling stability over 2500 h at 0.1mA cm-2. Full cells with a high-voltage LiNi0.8Co0.1Mn0.1O2 cathode exhibit high energy density and longterm cycling stability, even at a high loading of 8.2 mg cm-2. Incorporating 2D OCN nanosheets into the PVDF-based electrolyte and Li-metal anode provides an effective strategy for achieving safe and high-energy-density Li-metal batteries.