Hollow nanostructures with mesoporous shells are attractive for their advantageous structure-dependent high-efficiency electrochemical catalytic performances. In this work, a novel nanostructure of Fe-doped CoP hollow triangle plate arrays (Fe-CoP HTPAs) with unique mesoporous shells is designed and synthesized through a room-temperature postsynthetic ligand exchange reaction followed by a facile phosphorization treatment. The mild postsynthetic ligand exchange reaction of the presynthesized ZIF-67 TPAs with K [Fe(CN) ] in an aqueous solution at room temperature is of critical importance in achieving the final hollow nanostructure, which results in the production of CoFe(II)-PBA HTPAs that not only determine the formation of the interior voids in the nanostructure, but also provide the doping of Fe atoms to the CoP lattice. As expected, the as-prepared mesoporous Fe-CoP HTPAs exhibit pronounced activity for water splitting owing to the advantages of abundant active reaction sites, short electron and ion pathways, and favorable hydrogen adsorption free energy (ΔG ). For the hydrogen and oxygen evolution reactions with the Fe-CoP HTPAs in alkaline medium, the low overpotentials of 98 and 230 mV are observed, respectively, and the required cell voltage toward overall water splitting is only as low as 1.59 V for the driving current density of 10 mA cm .

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We introduce a facile route to fabricate one-dimensional (1D) porous Cu 2+ -doped BiVO 4 (Cu-BVO) nanotubes with uniform size distribution and high structural stability. First, an electrospinning technique was developed to prepare the sacrificial template of polyacrylonitrile (PAN) nanofibers with a smooth surface. Second, a conformal layer of Cu-BVO nanoparticles was coated onto the PAN template through a solvothermal method to obtain the solid core−shell precursor which was finally converted into the product of porous Cu-BVO nanotubes with thermal treatment. Both experimental characterizations and theoretical calculations based on the density functional theory (DFT) calculations have revealed the crucial functionality of the appropriate band structure of the Cu 2+ -doped nanostructure and introduced beneficial defect states by Cu doping, which boosts light absorption and promotes charge migration and separation and therefore results in highly efficient photocatalytic O 2 evolution with visible-light irradiation. As a result, the porous nanotube photocatalyst with an optimal Cu 2+ doping of 5.0% exhibits an average O 2 evolution rate of 350.2 μmol h −1 g −1 , about 2.4 times more than that of pristine BVO nanotubes.

We report detailed studies of quasibound states of a T-shaped two-dimensional quantum wire structure. While in the tunneling regime the peaks of the resonant transmission pattern correspond to quasibound states in the system, in the transmissive regime we show that the reflection peaks correspond to them. Furthermore, there is a one-to-one correspondence in energy and wave function between the quasibound states of the open structure and the bound state of the corresponding closed structure. We show that the quasibound states of the system can be unambiguously identified by the behavior of the electron dwell time.

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Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat model was used to evaluate the anti-allergic rhinitis effect of Shenqi. The effect of Shenqi on IgE-mediated degranulation was measured using rat basophilic leukemia (RBL-2H3) cells. Primary spleen lymphocytes were isolated to investigate the anti-allergic mechanism of Shenqi by detecting the expression of transcription factors via Western blot and the level of cytokines (IL-4 and IFN-γ) via ELISA. In OVA-induced AR rat models, Shenqi relieved the allergic rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and reduced the levels of IL-4 and IgE. The results from the in vitro study certified that Shenqi inhibited mast cell degranulation. Furthermore, the results of GATA3, T-bet, p-STAT6, and SOCS1 expression and production of IFN-γ and IL-4 demonstrated that Shenqi balanced the ratio of Th1/Th2 (IFN-γ/IL-4) in OVA-stimulated spleen lymphocytes. In conclusion, these results suggest that Shenqi exhibits an obvious anti-allergic effect by suppressing the mast cell-mediated allergic response and by improving the imbalance of Th1/Th2 ratio in allergic rhinitis.

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Background: Colorectal cancer remains one of the most common malignant tumors worldwide. Colorectal cancer initiating cells (CCICs) are a small subpopulation responsible for malignant behaviors of colorectal cancer. Aberrant activation of the Wnt pathways regulates the self-renewal of CCIC. However, the underlying mechanism(s) remain poorly understood.