Identification of the active site is important in developing rational design strategies for solid catalysts but is seriously blocked by their structural complexity. Here, we use uniform Cu ...nanocrystals synthesized by a morphology-preserved reduction of corresponding uniform Cu
O nanocrystals in order to identify the most active Cu facet for low-temperature water gas shift (WGS) reaction. Cu cubes enclosed with {100} facets are very active in catalyzing the WGS reaction up to 548 K while Cu octahedra enclosed with {111} facets are inactive. The Cu-Cu suboxide (Cu
O, x ≥ 10) interface of Cu(100) surface is the active site on which all elementary surface reactions within the catalytic cycle proceed smoothly. However, the formate intermediate was found stable at the Cu-Cu
O interface of Cu(111) surface with consequent accumulation and poisoning of the surface at low temperatures. Thereafter, Cu cubes-supported ZnO catalysts are successfully developed with extremely high activity in low-temperature WGS reaction.Nanocrystals display a variety of facets with different catalytic activity. Here the authors identify the most active facet of copper nanocrystals relevant to the low-temperature water gas shift reaction and further design zinc oxide-copper nanocubes with exceptionally high catalytic activity.
The design and assembly of photoelectro‐active molecular channel structures is of great importance because of their advantages in charge mobility, photo‐induced electron transfer, proton conduction, ...and exciton transport. Herein, we report the use of racemic 9,9′‐diphenyl‐2,2′‐bifluorene‐9,9′‐diol (DPFOH) enantiomers to produce non‐helical 1D channel structures. Although the individual molecule does not present any molecular symmetry, two pairs of racemic DPFOH enantiomers can form a C2‐symmetric closed loop via the stereoscopic herringbone assembly. Thanks to the special symmetry derived from the enantiomer pairs, the multiple supramolecular interactions, and the padding from solvent molecules, this conventionally unstable topological structure is achieved. The etching of solvent in 1D channels leads to the formation of microtubes, which exhibit a significant lithium‐ion conductivity of 1.77×10−4 S cm, indicating the potential research value of this novel 1D channel structure.
An unprecedented supramolecular non‐helical channel structure based on racemic 9,9′‐diphenyl‐2,2′‐bifluorene‐9,9′‐diol enantiomers is achieved. Two pairs of racemic enantiomers can form a C2‐symmetric closed loop via the stereoscopic herringbone assembly. The etching of solvent in 1D channels leads to the formation of microtubes with a lithium‐ion conductivity of 1.77×10−4 S cm.
Rationale
The volatile anesthetic isoflurane is suggested to produce a rapid and robust antidepressive effect in preliminary clinical trials. Recently, isoflurane was found to activate the ...tropomyosin receptor kinase B (TrkB) signaling which is the underlying mechanism of the rapid antidepressant ketamine.
Objective
Our study investigated the effect of isoflurane anesthesia on chronic unpredictable mild stressed (CUMS) model in mice and verified the role of brain-derived neurotrophic factor (BDNF)/TrkB/ the mammalian target of rapamycin (mTOR) signaling in the antidepressant effect of isoflurane.
Methods
We employed the CUMS model of depression to assess the rapid antidepressant effect of isoflurane by the forced swimming test (FST), the sucrose preference test (SPT), and the novelty suppressed feeding test (NSFT). The protein expression of BDNF and TrkB/protein kinase B (PKB or Akt)/mTOR was determined through Western blot. The dendritic spine density in the hippocampus and medial prefrontal cortex (PFC) was measured by the Golgi staining.
Results
A brief burst-suppressing isoflurane anesthesia rapidly reversed the behavioral deficits caused by CUMS procedure, normalized the expression of BDNF and further activated the TrkB signaling pathway in CUMS-induced stressed mice in both prefrontal cortex (PFC) and hippocampus (HC). All of those behavioral and proteomic effects were blocked by K252a, a selective receptor inhibitor of TrkB. Isoflurane significantly promoted the formation of dendritic spines in both medial prefrontal cortex (mPFC), CA1, CA3, and DG of the hippocampus.
Conclusion
Our study indicates that isoflurane exerts a rapid antidepressant-like effect in CUMS depression animal model, and the activation of BDNF/TrkB signaling pathway plays an indispensable role in the biological and behavioral antidepressant effects of isoflurane. A single exposure to isoflurane could repair synaptic damage caused by chronic stimulation.
The WC‐12%Cr3C2‐6%Ni coatings are prepared by high‐velocity oxygen‐fuel spraying technology on 42CrMo steel substrate, and then the sealing treatment is carried out by sol‐gel aluminum phosphate ...inorganic sealing agent. The composition, phase structure, morphologies, and porosities of the coatings are characterized by energy dispersive spectrometer (EDS), X‐ray diffraction, scanning electron microscope (SEM), and metallographic gray‐scale methods. Results show that the corrosion current density and corrosion rates of WC‐12%Cr3C2‐6%Ni coatings in different media are lessened by the aluminum phosphate sealing treatment, which can improve the corrosion resistance of the coating. The corrosion rates of unsealed and sealed coatings immersed in 3.5% Na2SO4 solution at 35℃ for 28 days are 0.99 and 0.38 g·m–2·h–1, and the porosity of the coatings is significantly decreased by the aluminum phosphate sealing treatment, which is lower than 2%. During the immersion corrosion, the sealed and unsealed coatings surface form oxide films with different compositions, which can slow down the corrosion along the normal direction of the coating surface in the process of continuous destruction and regeneration, and no obvious coating/substrate interface corrosion occurs.
The WC‐12%Cr3C2‐6%Ni coatings are prepared by HVOF spraying technology on 42CrMo steel substrate, and then the sealing treatment is carried out by sol‐gel aluminum phosphate inorganic sealing agent. The corrosion current density and corrosion rates of WC‐12%Cr3C2‐6%Ni coatings in different media are lessened by the aluminum phosphate sealing treatment which can decrease the residual cracks and porosities, and the porosities of sealed and unsealed coatings is lower than 2%.
Primary and acquired drug resistance is one of the main obstacles encountered in high-grade serous ovarian cancer (HGSC) chemotherapy. Cisplatin induces DNA damage through cross-linking and long ...integrated non-coding RNAs (lincRNAs) play an important role in chemical induced DNA-damage response, which suggests that lincRNAs may be also associated with cisplatin resistance. However, the mechanism of long integrated non-coding RNAs (lincRNAs) acting on cisplatin resistance is not well understood. Here, we showed that expression of lin-RECK-3, H19, LUCAT1, LINC00961, and linc-CARS2-2 was enhanced in cisplatin-resistant A2780-DR cells, while transcriptome sequencing showed decreased Linc-TNFRSF19-1 and LINC00515 expression. Additionally, we verified that different H19 expression levels in HGSC tissues showed strong correlation with cancer recurrence. H19 knockdown in A2780-DR cells resulted in recovery of cisplatin sensitivity in vitro and in vivo. Quantitative proteomics analysis indicated that six NRF2-targeted proteins, including NQO1, GSR, G6PD, GCLC, GCLM and GSTP1 involved in the glutathione metabolism pathway, were reduced in H19-knockdown cells. Furthermore, H19-knockdown cells were markedly more sensitive to hydrogen-peroxide treatment and exhibited lower glutathione levels. Our results reveal a previously unknown link between H19 and glutathione metabolism in the regulation of cancer-drug resistance.
Cuckoo search (CS) is a one of the most efficient evolutionary for global optimization and widely applied to solve diverse problems in the real world. Despite its efficiency and wide use, CS suffers ...from premature convergence and poor balance between exploitation and exploration. To cope with these issues, a new cuckoo search algorithm extension based on self-adaptive knowledge learning (I-PKL-CS) is proposed. In this study, learning model with individual history knowledge and population knowledge is introduced into the CS algorithm. Individuals constantly adjust their position by using historical knowledge and communicate with each other by using their own knowledge in the optimization process. In order to reduce complexity of the I-PKL-CS algorithm, the optimal learning model is selected to exploit the potential of individual knowledge learning and population knowledge learning by adopting threshold statistics learning strategy, which provides a good trade-off between the exploration and exploitation. The accuracy and performance of the proposed approach are evaluated by eighteen classic benchmark functions and CEC 2013 test suite. Statistical comparisons of the experimental results showed that the proposed I-PKL-CS algorithm made an appropriate trade-off between exploration and exploitation. Comparing the proposed I-PKL-CS with various CS algorithms, variants of differential evolution, and improved particle swarm optimization algorithms, the results demonstrate that I-PKL-CS is a competitive new type of algorithm.
Diamond‐like carbon (DLC) possesses brilliant and excellent properties, including excellent corrosion resistance as well as outstanding wear resistance. Ni and B co‐doped DLC films were deposited on ...AZ91D magnesium alloy by electrodeposition under mild conditions (300 V and 25°C). Uniform and dense morphology of co‐doped DLC films were observed, and Ni and B were uniformly incorporated into the carbon‐based films. Among all the electrodeposits, the appearance of D and G peaks near 1330 and 1570 cm−1 revealed that the as‐deposited films were typical DLC films. As the addition of Ni was increased to 0.05 g, the highest microindentation hardness, the lowest friction coefficient, and wear loss were achieved to be 164.5 HV, 0.3, and 0.6 × 10−5 kg/m, respectively. The amorphous carbon films fabricated at 0.05 g Ni had the lowest corrosion current density and the most positive corrosion potential, which was mainly due to the small and dense granular structure effectively hindering the penetration of corrosion media.
The B, Ni co‐doped diamond‐like carbon films prepared by low‐temperature liquid‐phase electrophoretic deposition on AZ91D magnesium alloys have better wear and corrosion resistance. In 3.5 wt% NaCl solution, the self‐corrosion potentials of the magnesium alloys‐coated diamond‐like carbon composite films were more positive than that of the bare magnesium alloy. Especially, the corrosion resistance was optimal when the Ni doping amount was 0.05 g/350 ml.
The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri ...fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4‐methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 μg mL−1. Further studies showed that 4‐methoxycoumarin affected the structure and function of peroxisomes, inhibited the β‐oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4‐Methoxycoumarin presented antifungal efficacy in a concentration‐ dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4‐methoxycournamin as an alternative and friendly biofungicide.
Oncofetal genes are genes that express abundantly in both fetal and tumor tissues yet downregulated or undetected in adult tissues, and can be used as tumor markers for cancer diagnosis and ...treatment. Meanwhile, long noncoding RNAs (lncRNAs) are known to play crucial roles in the pathogenesis of hepatocellular carcinoma (HCC), including tumor growth, proliferation, metastasis, invasion, and recurrence. We performed a genome-wide screening using microarrays to detect the lncRNA expression profiles in fetal livers, adult livers, and liver cancer tissues from mice to identify oncofetal lncRNAs in HCC. From the microarray data analysis, we identified lncRNA Ptn-dt as a possible oncofetal gene. Both in vitro and in vivo experiments results confirmed that overexpression of Ptn-dt significantly promoted the proliferation of mouse HCC cells. RNA pulldown assay showed that Ptn-dt could interact with the HuR protein. Interestingly, miR-96 binds with HuR to maintain its stability as well. Overexpression of lncRNA Ptn-dt led to the downregulation of miR-96, which might be due to the interaction between Ptn-dt and HuR. Meanwhile, previous studies have reported that Ptn can promote tumor growth and vascular abnormalization via anaplastic lymphoma kinase (Alk) signaling. In our study, we found that overexpression of Ptn-dt could promote the expression of Alk through repressing miR-96 via interacting with HuR, thus enhancing the biologic function of Ptn. In summary, a new oncofetal lncRNA Ptn-dt is identified, and it can promote the proliferation of HCC cells by regulating the HuR/miR-96/Alk pathway and Ptn-Alk axis.
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