Defect and interface engineering are recognized as effective strategies to regulate electronic structure and improve activity of metal sulfide. However, the practical application of sulfide is ...restricted by their low conductivity and rapid decline in activity derived from large volume fluctuation during electrocatalysis process. More importantly, the determination of exact active site of sulfide is complicated due to the inevitable electrochemical reconstruction. Herein, ZnS nanoparticles with Zn defect are anchored onto the surface of NiCo2S4 nanosheet to construct NiCo2S4/ZnS hybrids, which exhibit outstanding oxygen evolution performance with an ultralow overpotential of 140 mV. The anchoring of defective ZnS nanoparticles inhibit the volume expansion of NiCo2S4 nanosheet during the cycling process. Density‐functional theory reveals that the build‐in interfacial potential and Zn defect can facilitate the thermodynamic formation of *O to *OOH, thus improve their intrinsic activity.
The NiCo2S4/ZnS hybrid catalyst with abundant Zn defects exhibits an outstanding OER performance, demonstrated by an ultralow overpotential of 140 mV. DFT calculations reveal that the built‐in interfacial potential and Zn defects can facilitate the thermodynamic formation of *O to *OOH, thus improving the intrinsic catalytic performance. This study provides a simple strategy for the construction of heterojunctions with defects.
Baicalin, which is isolated from Radix Scutellariae, possesses strong biological activities including an anti-inflammation property. Recent studies have shown that the anti-inflammatory effect of ...baicalin is linked to toll-like receptor 4 (TLR4), which participates in pathological changes of central nervous system diseases such as depression. In this study, we explored whether baicalin could produce antidepressant effects via regulation of TLR4 signaling in mice and attempted to elucidate the underlying mechanisms.
A chronic unpredictable mild stress (CUMS) mice model was performed to explore whether baicalin could produce antidepressant effects via the inhibition of neuroinflammation. To clarify the role of TLR4 in the anti-neuroinflammatory efficacy of baicalin, a lipopolysaccharide (LPS) was employed in mice to specially activate TLR4 and the behavioral changes were determined. Furthermore, we used LY294002 to examine the molecular mechanisms of baicalin in regulating the expression of TLR4 in vivo and in vitro using western blot, ELISA kits, and immunostaining. In the in vitro tests, the BV2 microglia cell lines and primary microglia cultures were pretreated with baicalin and LY292002 for 1 h and then stimulated 24 h with LPS. The primary microglial cells were transfected with the forkhead transcription factor forkhead box protein O 1 (FoxO1)-specific siRNA for 5 h and then co-stimulated with baicalin and LPS to investigate whether FoxO1 participated in the effect of baicalin on TLR4 expression.
The administration of baicalin (especially 60 mg/kg) dramatically ameliorated CUMS-induced depressive-like symptoms; substantially decreased the levels of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) in the hippocampus; and significantly decreased the expression of TLR4. The activation of TLR4 by the LPS triggered neuroinflammation and evoked depressive-like behaviors in mice, which were also alleviated by the treatment with baicalin (60 mg/kg). Furthermore, the application of baicalin significantly increased the phosphorylation of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and FoxO1. The application of baicalin also promoted FoxO1 nuclear exclusion and contributed to the inhibition of the FoxO1 transactivation potential, which led to the downregulation of the expression of TLR4 in CUMS mice or LPS-treated BV2 cells and primary microglia cells. However, prophylactic treatment of LY294002 abolished the above effects of baicalin. In addition, we found that FoxO1 played a vital role in baicalin by regulating the TLR4 and TLR4-mediating neuroinflammation triggered by the LPS via knocking down the expression of FoxO1 in the primary microglia.
Collectively, these results demonstrate that baicalin ameliorated neuroinflammation-induced depressive-like behaviors through the inhibition of TLR4 expression via the PI3K/AKT/FoxO1 pathway.
Abstract
We consider finite Morse index solutions to semilinear elliptic questions, and we investigate their smoothness. It is well‐known that:
For , there exist Morse index 1 solutions whose norm ...goes to infinity.
For , uniform boundedness holds in the subcritical case for power‐type nonlinearities, while for critical nonlinearities the boundedness of the Morse index does not prevent blow‐up in .
In this paper, we investigate the case of general supercritical nonlinearities inside convex domains, and we prove an interior a priori bound for finite Morse index solution in the sharp dimensional range . As a corollary, we obtain uniform bounds for finite Morse index solutions to the Gelfand problem constructed via the continuity method.
Major depressive disorder (MDD) is common and disabling, but its neuropathophysiology remains unclear. Most studies of functional brain networks in MDD have had limited statistical power and data ...analysis approaches have varied widely. The REST-meta-MDD Project of resting-state fMRI (R-fMRI) addresses these issues. Twenty-five research groups in China established the REST-meta-MDD Consortium by contributing R-fMRI data from 1,300 patients with MDD and 1,128 normal controls (NCs). Data were preprocessed locally with a standardized protocol before aggregated group analyses. We focused on functional connectivity (FC) within the default mode network (DMN), frequently reported to be increased in MDD. Instead, we found decreased DMN FC when we compared 848 patients with MDD to 794 NCs from 17 sites after data exclusion. We found FC reduction only in recurrent MDD, not in first-episode drug-naïve MDD. Decreased DMN FC was associated with medication usage but not with MDD duration. DMN FC was also positively related to symptom severity but only in recurrent MDD. Exploratory analyses also revealed alterations in FC of visual, sensory-motor, and dorsal attention networks in MDD. We confirmed the key role of DMN in MDD but found reduced rather than increased FC within the DMN. Future studies should test whether decreased DMN FC mediates response to treatment. All R-fMRI indices of data contributed by the REST-meta-MDD consortium are being shared publicly via the R-fMRI Maps Project.
The quantity and quality of peanut yields are seriously compromised by consecutive monoculture in the subtropical regions of China. Root exudates, which represent a growth regulator in peanut–soil ...feedback processes, play a principal role in soil sickness. The growth inhibition of a species in an in vitro bioassay enriched with root exudates and allelochemicals is commonly viewed as evidence of an allelopathic interaction. However, for some of these putative examples of allelopathy, the results have not been verified in more natural settings with plants continuously growing in soil. In this study, the phenolic acids in peanut root exudates, their retention characteristics in an Udic Ferrosol, and their effects on rhizosphere soil microbial communities and peanut seedling growth were studied. Phenolic acids from peanut root exudates were quickly metabolized by soil microorganisms and did not accumulate to high levels. The peanut root exudates selectively inhibited or stimulated certain communal bacterial and fungal species, with decreases in the relative abundance of the bacterial taxa Gelria glutamica, Mitsuaria chitosanitabida, and Burkholderia soli and the fungal taxa Mortierella sp. and Geminibasidium hirsutum and increases in the relative abundance of the bacterial taxon Desulfotomaculum ruminis and the fungal taxa Fusarium oxysporum, Bionectria ochroleuca and Phoma macrostoma. The experimental application of phenolic acids to non-sterile and sterile soil revealed that the poor performance of the peanut plants was attributed to changes in the soil microbial communities promoted by phenolic acids. These results suggest that pathogenic fungal accumulation at the expense of such beneficial microorganisms as plant growth promoting rhizobacteria, mycorrhizal fungi induced by root exudates, rather than direct autotoxicity induced by root exudates, might represent the principal cause underlying the soil sickness associated with peanut plants. We hope that our study will motivate researchers to integrate the role of soil microbial communities in allelopathic research, such that their observed significance in soil sickness during continuous monocropping of fields can be further explored.
•Phenolic acids were mostly metabolized by microbes rather than accumulation in soil.•Peanut root exudates increased pathogenic fungi and decreased beneficial microbes.•Pseudomonads community responded sensitively to peanut root exudates.•Bad peanut performance was due to changes of soil microbes incited by phenolic acids.
Objective
Surgical treatment with internal fixation, specifically percutaneous fixation with three cannulated compression screws (CCSs), is the preferred choice for young and middle‐aged patients. ...The mechanical advantage of the optimal spatial configuration with three screws provides maximum dispersion and cortical support. We suspect that the spatial proportion of the oblique triangle configuration (OTC) in the cross‐section of the femoral neck isthmus (FNI) may significantly improve shear and fatigue resistance of the fixed structure, thereby stabilizing the internal fixation system in femoral neck fracture (FNF). This study aims to explore the mechanical features of OTC and provide a mechanical basis for its clinical application.
Methods
Twenty Sawbone femurs were prepared as Pauwels type III FNF models and divided equally into two fixation groups: OTC and inverted equilateral triangle configuration (IETC). Three 7.3 mm diameter cannulated compression screws (CCSs) were used for fixation. The specimens of FNF after screw internal fixation were subjected to static loading and cyclic loading tests, respectively, with five specimens for each test. Axial stiffness, 5 mm failure load, ultimate load, shear displacement, and frontal rotational angle of two fragments were evaluated. In the cyclic loading test, the load sizes were 700 N, 1400 N, and 2100 N, respectively, and the fracture end displacement was recorded. Results were presented as means ± SD. Data with normal distributions were compared by the Student's t test.
Results
In the static loading test, the axial stiffness, ultimate load, shear displacement, and frontal rotational angle of two fragments were (738.64 vs. 620.74) N/mm, (2957.61 vs. 2643.06) N, (4.67 vs. 5.39) mm, and (4.01 vs. 5.52)° (p < 0.05), respectively. Comparison between the femoral head displacement after 10,000 cycles of 700N cyclic loading and total displacement after 20,000 cycles of 700–1400N cyclic loading showed the OTC group was less than the IETC group (p < 0.05). A comparison of femoral head displacement after 10,000 cycles of 1400N and 2100N cycles and total displacement after 30,000 cycles of 700–2100N cycles showed the OTC group was less than another group, but the difference was not significant (p > 0.05).
Conclusion
When three CCSs are inserted in parallel to fix FNF, the OTC of three screws has obvious biomechanical advantages, especially in shear resistance and early postoperative weight‐bearing, which provides a mechanical basis for clinical selection of ideal spatial configuration for unstable FNF.
In this study, 20 fourth‐generation Sawbone femurs were used to evaluate the fixation mechanics of two screw space configurations (OTC triangle configuration and IETC inverted equilateral triangle configuration) for femoral neck fractures. During the experiment, static load test and cyclic load test were carried out on FNF specimens after internal screw fixation. The evaluation indexes of the static load test were axial stiffness, 5 mm failure load, ultimate load, shear displacement and front rotation angle of the two fragments. The cyclic loading test loads were 700N, 1400N, and 2100N, respectively, and the evaluation index was fracture end displacement. The study verified the mechanical advantages of OTC through in vitro biomechanical experiments, and to provide mechanical basis for its clinical application.
Combination therapy has attracted extensive interest in alleviating the shortcomings of monotherapy and enhancing the treatment efficacy. In this work, hollow mesoporous silica nanoparticles (HMSNs) ...play the role of nanocarriers in the delivery of Cu(II)-doped polydopamine (PDA), termed as HMSNs@PDA-Cu, for synergistic therapy. PDA acts as a traditional photothermal agent to realize photothermal treatment (PTT). Chemodynamic therapy (CDT) is realized by the reaction of Cu(II) with intracellular glutathione (GSH), and subsequently, the generated Cu(I) reacts with H2O2 to produce toxic hydroxyl radical (•OH) through a Fenton-like reaction. The photothermal performance of PDA is improved after its coordination with Cu(II). On the other hand, PDA exhibits superoxide dismutase (SOD)-mimicking activity. PDA converts O2 •– to H2O2 and improves the production of H2O2, which promotes the therapeutic effect of CDT. Moreover, the high temperature caused by PTT further enhances the yield of •OH for CDT. This nanotheranostic platform perfectly applied to the tumor depletion of mice, presenting great potential for cancer metastasis therapy in vitro and in vivo.
Owing to the high spatial resolution at the atomic scale, the transmission electron microscopy (TEM) or scanning transmission electron microscopy is demonstrated as a promising characterization ...method to unveil the charge storage mechanism of electrode materials in Li-ion batteries. The structural evolution of electrode materials during charge/discharge process can be directly observed by using TEM. The detailed analysis establishes a relationship between the structure of electrode material and battery performance. Herein, we present a brief review of the atomic-scale characterization in Li-ion batteries, including Li (de)insertion mechanism (both cations and anions charge-compensation mechanism), migration of transition metal ions, and surface phase transition. The in-depth microscopic analysis reveals the detailed structural characteristics, which influence the properties of LIBs, establish the structure–function relationship, and facilitate the development of Li-ion batteries.
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