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MXene is investigated as an electrode material for different energy storage systems due to layered structures and metal-like electrical conductivity. Experimental results show MXenes possess excellent cycling performance as anode materials, especially at large current densities. However, the reversible capacity is relatively low, which is a significant barrier to meeting the demands of industrial applications. This work synthesizes N-doped graphene-like carbon (NGC) intercalated Ti3C2Tx (NGC-Ti3C2Tx) van der Waals heterostructure by an in situ method. The as-prepared NGC-Ti3C2Tx van der Waals heterostructure is employed as sodium-ion and lithium-ion battery electrodes. For sodium-ion batteries, a reversible specific capacity of 305 mAh g-1 is achieved at a specific current of 20 mA g-1, 2.3 times higher than that of Ti3C2Tx. For lithium-ion batteries, a reversible capacity of 400 mAh g-1 at a specific current of 20 mA g-1 is 1.5 times higher than that of Ti3C2Tx. Both sodium-ion and lithium-ion batteries made from NGC-Ti3C2Tx shows high cycling stability. The theoretical calculations also verify the remarkable improvement in battery capacity within the NGC-Ti3C2O2 system, attributed to the additional adsorption of working ions at the edge states of NGC. This work offers an innovative way to synthesize a new van der Waals heterostructure and provides a new route to improve the electrochemical performance significantly.

Background: The relation between the human body movements and cognition has been a research hotspot in physical education and health promotion in recent years. This study applied the embodied cognition theory to examine the effects of the Movement Integrity with Intelligent Play (MIIP) program on preschoolers' math performance. Objective: This study explores whether the Movement Integrity with Intelligent Play is connected with math performance, physical activity (PA) levels, and enjoyment of kindergarten students. Method: A quasi-experimental trial was delivered to evaluate the effects of the MIIP program that integrated bodily movements into math cognitive tasks related to pattern cognitive skills. A total of 54 (N = 54, 30 girls, M[subscript age] = 75.69 ± 3.36) children from two preschool classrooms served as participants and were assigned to one of the following two conditions: the integrated condition group (ICG, n = 28), and the conventional condition group (CCG, n = 26). During a 2-week intervention period, the ICG received a task-relevant PA (3×30 min/wk) in addition to their regular in-school math lessons (2×30 min/wk). Finally, math performance, PA levels, and enjoyment were assessed. Results: Following the intervention, significant differences (p < 0.05) in math performance, PA levels, and enjoyment were found in the ICG. The results demonstrated that preschool children in ICG outperformed children in the CCG. Children in the CCG showed no significant differences in math performance and PA levels. In addition, children in the ICG scored higher scores (M = 9.25 ± 2.71) on perceived enjoyment of the instructional method than children in the CCG (M = 7.07 ± 3.91). Conclusions: The integrated intervention has beneficial effects not only on math performance, PA levels but also on enjoyment. Transforming the focus of instruction to an integrated PA enhanced both math performance, PA levels, and increased enjoyment.

AIM: To explore the dynamic expression of high mobility group box 1(HMGB1)in scar tissues after glaucoma drainage valve implantation, and to further reveal the role and possible mechanism of HMGB1 in scarring after glaucoma surgery.METHODS: A total of 60 New Zealand white rabbits were randomly divided into control group(n=20), model group(n=20, silicone implantation under conjunctival sac)and model with drug administration group(n=20, silicone implantation under conjunctival sac combined with 5-fluorouracil injection). The conjunctival tissues were collected at 4 and 8 wk after surgery. HE staining and Masson staining were used to detect the proliferation and distribution of fibroblasts and collagen fibers in conjunctival tissues. Immunohistochemistry was utilized to detect the distribution and changes of HMGB1, transforming growth factor(TGF)-β1, Smad3 and α-smooth muscle actin(SMA)in conjunctival tissues. RT-PCR and Western blot were adopted to detect the mRNA and protein expression of HMGB1, TGF-β1, Smad3 and α-SMA in conjunctival tissues.RESULTS: HE staining and Masson staining showed that the proliferation of inflammatory cells, fibroblasts and collagen fibers in the model group was significantly higher than that in the control group at both 4 and 8 wk. Meanwhile, the proliferation of fibroblasts and collagen fibers in the model with drug administration group was significantly lower than that in the model group. Immunohistochemical staining showed that the expression of HMGB1, TGF-β1, Smad3 and α-SMA protein was observed in the conjunctival tissues of the model group both 4 and 8 wk, with brown and significantly deeper staining of the model group at 8 wk. Meanwhile, the positive staining in the model with drug administration group at both 4 and 8 wk was significantly lower than that in the model group. There was positive correlations between the number of fibroblasts stained with HE and the expression of HMGB1 in the conjunctival tissue of the model group at both 4 and 8 wk(r=0.602, 0.703, all P

Two-dimensional transition-metal carbides and nitrides "MXenes" have demonstrated great potential as electrode materials for electrochemical energy storage systems. This is especially true for delaminated Ti3C2Tx, which already shows outstanding gravimetric and volumetric capacitance, with areal capacitance limited by thickness (only a few microns). However, the performance of multilayer Ti3C2Txhas been more modest. Here, we report on using metal cation (viz., Na+, K+, and Mg2+) pre-intercalated multilayer Ti3C2Txas electrodes for aqueous supercapacitors. These electrodes are scalable and amenable to roll-to-roll manufacturing, with adjustable areal loadings of 5.2 to 20.1 mg/cm2. K-Ti3C2Txexhibited the highest capacitances at different scan rates. A gravimetric capacitance comparable to that of delaminated MXene of up to 300 F/g was achieved for multilayer K-Ti3C2Txbut with an outstanding ultra-high areal capacitance of up to 5.7 F/cm2, which is 10-fold higher than the 0.5 F/cm2of delaminated MXene and exceeds the 4.0 F/cm2of microengineered MXene electrodes.

MXene-transition metal dichalcogenide (TMD) heterostructures are synthesized through a one-step heat treatment of Nb2C and Nb4C3. These MXenes are used without delamination or any pre-treatment. Heat treatments accomplish the sacrificial transformation of these MXenes into TMD (NbS2) at 700 and 900 °C under H2S. This work investigates, for the first time, the role of starting MXene phase in the derivative morphology. It is shown that while treatment of Nb2C at 700 °C leads to the formation of pillar-like structures on the parent MXene, Nb4C3 produces nano-mosaic layered NbS2. At 900 °C, both MXene phases, of the same transition metal, fully convert into nano-mosaic layered NbS2 preserving the parent MXene's layered morphology. When tested as electrodes for hydrogen evolution reaction, Nb4C3-derived hybrids show better performance than Nb2C derivatives. The Nb4C3-derived heterostructure exhibits a low overpotential of 198 mV at 10 mA cm−2 and a Tafel slope of 122 mV dec−1, with good cycling stability in an acidic electrolyte.