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Enabling materials to undergo reversible dynamic transformations akin to the behaviors of living organisms represents a critical challenge in the field of material assembly. The pursuit of such capabilities using conventional materials has largely been met with limited success. Herein, the discovery of reversible constrained dissociation and reconfiguration in MXene films, offering an effective solution to overcome this obstacle is reported. Specifically, MXene films permit rapid intercalation of water molecules between their distinctive layers, resulting in a significant expansion and exhibiting confined dissociation within constrained spaces. Meanwhile, the process of capillary compression driven by water evaporation reinstates the dissociated MXene film to its original compact state. Further, the adhesive properties emerging from the confined disassociation of MXene films can spontaneously induce fusion between separate films. Utilizing this attribute, complex structures of MXene films can be effortlessly foamed and interlayer porosity precisely controlled, using only water as the inducer. Additionally, a parallel phenomenon has been identified in graphene oxide films. This work not only provides fresh insights into the microscopic mechanisms of 2D materials such as MXene but also paves a transformative path for their macroscopic assembly applications in the future. [ABSTRACT FROM AUTHOR]

Heteroatom doping can efficiently tailor the physicochemical properties of 2D MXene materials for enhancing the energy storage performance. However, in mostly applied doping strategies, the wet chemistry method typically suffers tedious separation and abstersion process while the solid‐phase thermal strategy (traditional furnace heating) employed long‐time （several hours） high‐temperature treatment may cause degradation of MXene. In this work, a universal, energy efficient and environmental‐friendly strategy is reported to realize the heteroatom doping of MXene within seconds by microwave‐induced targeted thermal shock. The MXene film can self‐heat to >800 °C within seconds followed by generating dazzling plasma under microwave field. The high temperature combined with plasma create a localized ultrahigh‐energy environment in MXenes, which promotes the rapid decomposition of preloaded dopant precursors and lattice/surface functional group substitutions between dopant atoms and MXene. The resulted nitrogen (N) and sulfur (S) co‐doped MXene showed significantly improved capacity and performance stability under deformations. Compared with the traditional furnace heating, the targeted heating strategy have significantly higher energy and time efficiencies and reduced carbon footprint. In addition, this method can be readily extended to various element doping of MXene. The microwave‐induced targeted thermal‐shock represents a general and efficient strategy for the fast heteroatom doping of MXene. [ABSTRACT FROM AUTHOR]

Droplet manipulation plays an important role in many fields, and smart adhesion control on superhydrophobic surfaces is widely accepted as an effective strategy. However, some imperfections such as long response time and deformable elastic materials are still difficult to be avoided for existing methods. Herein, a new strategy is reported to reversibly control the surface adhesion and droplet's sliding without the change of surface chemistry and microstructure. A novel superhydrophobic surface is prepared by integrating a substrate with a certain size of NdFeB magnetic region and a hydrophobic SiO2 coating. The magnetic region on the surface is highly adhesive, which can pin a superparamagnetic droplet tightly. As an external magnet (EM) with opposite direction of magnetic flow to the NdFeB magnetic region is put above the droplet, the droplet rolls off as the surface is tilted, indicating that the high adhesive region has turned into the low adhesive state and in situ droplet's sliding control is realized. After removing the EM, the magnetic region on the surface can regain the high adhesion, demonstrating an excellent controllability. Finally, based on the smart controllability, the surface with several magnetic regions is designed and on‐demand storage/release control of different droplets is demonstrated. [ABSTRACT FROM AUTHOR]

Water is a significant and abundant resource as well as a pure natural energy source. Many researchers have been reported on humidity‐responsive actuators that mimick the humidity responsive behavior that widely exists in nature. Benefiting from advantages such as hydrophilicity, high electrical conductivity, and good dispersibility, MXenes (Ti3C2Tx) show promising performance when applied to humidity‐responsive actuators. This Minireview describes the preparation methods and structural characteristics of MXenes, and the mechanism of humidity‐responsive actuators. Recent important advances of MXene materials in actuators are objectively reviewed and evaluated, and existing issues are discussed. In addition, the development of these systems is outlined from the aspects of MXene preparation, structure control, design and assembly, and applications, and provides new ideas and guidance for the development of the next generation of high‐performance MXene‐based humidity‐responsive actuators. [ABSTRACT FROM AUTHOR]

MXene (Ti3C2Tx) is a new 2D material with both hydrophilicity and high electrical conductivity, and it has shown promise in smart electronic devices. Reported herein is a homogeneous MXene film actuator with high electrical conductivity triggered by moisture gradients. The actuator is highly sensitive to moisture and undergoes deformation, with the maximum bending angle as high as 155° at a relative humidity difference of 65 %. Several analysis methods show that the humidity drive and large deformation of the MXene film occur in situ by asymmetric expansion of the bilayer structure. The combination of deformation and electrical conductivity makes this film applicable to flexible excavators, electrical switches, and other fields, applications that are difficult to achieve directly by using other 2D materials. More importantly, this work further expands the new application range of MXene materials and provides new opportunities for building the next generation of high‐conductivity smart actuators. [ABSTRACT FROM AUTHOR]

Abstract: Heart failure has become one of the top causes of death worldwide. It is increasing evidence that lncRNAs play important roles in the pathology processes of multiple cardiovascular diseases. Additionally, lncRNAs can function as ceRNAs by sponging miRNAs to affect the expression level of mRNAs, implicating in numerous biological processes. However, the functional roles and regulatory mechanisms of lncRNAs in heart failure are still unclear. In our study, we constructed a heart failure‐related lncRNA‐mRNA network by integrating probe re‐annotation pipeline and miRNA‐target interactions. Firstly, some lncRNAs that had the central topological features were found in the heart failure‐related lncRNA‐mRNA network. Then, the lncRNA‐associated functional modules were identified from the network, using bidirectional hierarchical clustering. Some lncRNAs that involved in modules were demonstrated to be enriched in many heart failure‐related pathways. To investigate the role of lncRNA‐associated ceRNA crosstalks in certain disease or physiological status, we further identified the lncRNA‐associated dysregulated ceRNA interactions. And we also performed a random walk algorithm to identify more heart failure‐related lncRNAs. All these lncRNAs were verified to show a strong diagnosis power for heart failure. These results will help us to understand the mechanism of lncRNAs in heart failure and provide novel lncRNAs as candidate diagnostic biomarkers or potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Purpose: Raman spectroscopy was explored to diagnose normal, benign, and malignant human breast tissues based on principal component analysis (PCA) and support vector machine-recursive feature elimination (SVM-RFE), and SVM-RFE results were compared with PCA. Methods: 1800 Raman spectra were acquired from fresh samples of human breast tissues (normal, fibroadenoma, adenosis, galactoma, and invasive ductal carcinoma) from 168 patients. After set up the SVM-RFE and PCA models, Mahalanobis distance, spectral residuals, sensitivity, specificity, and Matthews correlation coefficient (MCC) were used as the discriminating criteria for evaluating these two methods. Results: The comparison shows that SVM-RFE based on the selection of characteristic peaks better reflects the nature of biopsy and it produces better discrimination, sensitivity, specificity, and MCC for normal (1, 1, 1), malignant (0.93, 0.97, 0.91), and benign (0.95, 0.97, 0.91) breast tissues. Conclusions: The Raman spectroscopy combined with SVM-RFE opens great future in the clinical applications of mammary disease diagnosis. [ABSTRACT FROM AUTHOR]

MXene (Ti3C2Tx) is renowned for its exceptional conductivity and hydrophilicity; however, the low yield of monolayers hinders its industrial scalability. Herein, we present a strategy to substantially enhance the monolayer yield by disrupting the hydrogen‐bonding cage confinement of multilayer MXene using high‐temperature ultrasound, challenging the conventional belief that monolayer MXene can only be prepared at lower temperatures. At approximately 70 °C, the weakened hydrogen bonding between the oxygen‐containing terminal groups of multilayer MXene and surrounding water molecules weakens the hydrogen‐bond cage confinement. This enables ultrasonic cavitation to generate more microbubbles that penetrate the interlayers of multilayer MXene, resulting in gentle and thorough delamination into larger monolayer nanosheets. Achieving up to a 95 % yield in just tens of minutes, these nanosheets exhibit properties comparable to those produced by traditional ice‐bath methods. Furthermore, the high‐concentration MXene ink produced on a large scale using this high‐yield approach exhibits excellent printing and processing capabilities, and the corresponding products showcase superior infrared stealth and Joule heating characteristics. This work addresses a key technical bottleneck in MXene production, paving the way for its extensive technological and industrial applications. [ABSTRACT FROM AUTHOR]

MXene films are attractive for advanced supercapacitor electrodes requiring high volumetric energy density due to their high redox capacitance combined with extremely high packing density. However, the self‐restacking of MXene flakes unavoidably decreases the volumetric performance, mass loading, and rate capability. Herein, a simple strategy is developed to prepare a flexible and free‐standing modified MXene/holey graphene film by filtration of the alkalized MXene and holey graphene oxide dispersions, followed by a mild annealing treatment. After terminal groups (F/OH) are removed, the increased proportion of Ti atoms enables more pseudocapacitive reaction. Meanwhile, the embedded holey graphene effectively prevents the self‐restacking of MXene and forms a high nanopore connectivity network, which is able to immensely accelerate the ion transport and shorten transport pathways for both ion and electron. When applied as electrode materials for supercapacitors, it can deliver an ultrahigh volumetric capacitance (1445 F cm−3) at 2 mV s−1, excellent rate capability, and high mass loading. In addition, the assembled symmetric supercapacitor demonstrates a fantastic volumetric energy density (38.6 Wh L−1), which is the highest value reported for MXene‐based electrodes in aqueous electrolytes. This work opens a new avenue for the further exploration of MXene materials in energy storage devices. A modified MXene/holey graphene film with a high nanopore connectivity network and satisfactory density is successfully prepared. The removed terminal fluorine and oxygen on the surface of MXene can enable more pseudocapacitance, and the embedded holey graphene can create an unimpeded channel for electrolyte ions. Consequently, the composite films demonstrate ultrahigh volumetric capacitance accompanied with superior rate capability and mass loading. [ABSTRACT FROM AUTHOR]