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WOS: 000444554700003, PubMed ID: 29796531, The relative stabilities of different chemical arrangements of Pd-Ir and Au-Rh nanoalloys (and their pure metal equivalents) are studied, for a range of compositions, for fcc truncated octahedral 38- and 79-atom nanoparticles (NPs). For the 38-atom NPs, comparisons are made of pure and alloy NPs supported on a TiO2(110) slab. The relative energies of different chemical arrangements are found to be similar for Pd-Ir and Au-Rh nanoalloys, and depend on the cohesive and surface energies of the component metals. For supported nanoalloys on TiO2, the interaction with the surface is greater for Ir (Rh) than Pd (Au): most of the pure NPs and nanoalloys preferentially bind to the TiO2 surface in an edge-on configuration. When Au-Rh nanoalloys are bound to the surface through Au, the surface binding strength is lower than for the pure Au NP, while the Pd-surface interaction is found to be greater for Pd-Ir nanoalloys than for the pure Pd NP. However, alloying leads to very little difference in Ir-surface and Rh-surface binding strength. Comparing the relative stabilities of the TiO2-supported NPs, the results for Pd-Ir and Au-Rh nanoalloys are the same: supported Janus NPs, whose Ir (Rh) atoms bind to the TiO2 surface, bind most strongly to the surface, becoming closer in energy to the core-shell configurations (Ir@Pd and Rh@Au) which are favoured for the free particles., Xiamen University; EPSRC Critical Mass Grant TOUCAN [EP/J010804/1]; EPSRC [EP/L000202]; TOUCAN grant; Royal Society International Exchange Grant [IE140712], T-EF is grateful for funding from the Graduate School of Xiamen University. RLJ and ID acknowledge support through EPSRC Critical Mass Grant (EP/J010804/1) TOUCAN. Calculations were performed on the following HPC facilities: The University of Birmingham Bluebear HPC facility (see http://www.bear.bham.ac.uk/bluebear for more details) and the UK's national HPC facility, ARCHER, both via membership of the UK's HPC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202), and via the TOUCAN grant. ZYL acknowledges Royal Society International Exchange Grant IE140712. LP acknowledges the French METSA network and Corinne Ulhaq (IPCMS, Strasbourg) for STEM imaging of Pd-Ir nanoparticles.

Aerodynamic characteristics of a stratospheric airship in its entire flight envelope, including take-off, ascending, cruising, descending, and landing, is an important part of its research topic. In this paper, experiments of wind pressure measurement on a 1/30-scale stratospheric airship model were carried out to obtain a better assessment of the aerodynamic characteristics during the cruising process. Based on the wind pressure distribution, the effects of pitch angle, yaw angle, and combined angles (pitch angle and yaw angle acted simultaneously) on the aerodynamics of the airship were analyzed. In addition, the contributions of different portions of the airship hull (namely head, middle, and tail) to the aerodynamic forces and moments were discussed. The experimental results imply that the tail portion is the main contributor to pressure drag force. The combined angles significantly increase aerodynamic forces and rolling moment, and the rolling moment produced by the middle portion accounts for the major proportion. Secondly, the computational fluid dynamics method was verified and employed to study the aerodynamic characteristics of the full-scale model in its entire flight envelope based on the decision of the wind environment parameters and attitude. As a main result, it can be concluded that, more attention should be paid to the airship when it is located in the troposphere and near the ground with an inclined take-off angle.

In this work, an electroanalytical platform for nereistoxin (NRT)-related insecticide detection is proposed on the basis of NRT induced DNA conformational switching and exonuclease III (Exo III) assisted target recycling. NRT-related insecticides were first hydrolyzed and converted into NRT with two thiol groups (–SH). Then, a cytosine–Ag+–cytosine (C–Ag+–C) mismatched base pair was adopted to induce a blunt-ended hairpin configuration of HP DNA. In the presence of converted NRT, it could take up Ag+ from HP DNA to change its conformation from a hairpin to single-stranded structure (HP ssDNA). Thereafter, the obtained HP ssDNA was further hybridized with an H1 hairpin probe on the electrode surface to trigger the Exo III cleavage process, releasing HP ssDNA for recycling leaving the G-quadruplex fragment of H1, which was used for hemin/G-quadruplex complex formation. The reversible redox reaction of Fe(III)/Fe(II) of hemin gave a remarkable electrochemical response for quantitative determination of the NRT-related insecticides. As an analytical model, a low detection limit of 3.9 ng L−1 and a wide linear range of 0.01–1500 μg L−1 with excellent selectivity were achieved for cartap detection. The proposed method also displayed great applicability for cartap detection in agricultural products.

The structures and surface adsorption sites of Pd-Ir nanoalloys are crucial to the understanding of their catalytic performance because they can affect the activity and selectivity of nanocatalysts. In this article, density functional theory (DFT) calculations are performed on bare Pd-Ir nanoalloys to systematically explore their stability and chemical ordering properties, before studying the adsorption of CO on the nanoalloys. First, the structural stability of 38-atom and 79-atom truncated octahedral (TO) Pd-Ir nanoalloys are investigated. Then the adsorption properties and preferred adsorption sites of CO on 38-atom Pd-Ir nanoalloys are considered. The PdshellIrcore structure, which has the lowest energy of all the considered isomers, exhibits the highest structural stability, while the PdcoreIrshell configuration is the least stable. In addition, the adsorption strength of CO on Ir atoms is found to be greater than on Pd for Pd-Ir nanoclusters. The preferred adsorption sites of CO on pure Pd and Ir clusters are in agreement with calculations and experiments on extended Pd and Ir surfaces. In addition, d-band center and charge effects on CO adsorption strength on Pd-Ir nanoalloys are analyzed by comparison with pure clusters. The study provides a valuable theoretical insight into catalytically active Pd-Ir nanoalloys.

Activation of the inward rectifier potassium current (IK1) channel has been reported to be associated with suppression of ventricular arrhythmias. In this study, we tested the hypothesis that opening of the IK1 channel with zacopride (ZAC) was involved in the modulation of tissue repair after myocardial infarction. Sprague-Dawley rats were subject to coronary artery ligation and ZAC was administered intraperitoneally (15 µg/kg/day) for 28 days. Compared with the ischemia group, treatment with ZAC significantly reduced the ratio of heart/body weight and the cross-sectional area of cardiomyocytes, suggesting less cardiac hypertrophy. ZAC reduced the accumulation of collagen types I and III, accompanied with decrease of collagen area, which were associated with a reduction of collagen deposition in the fibrotic myocardium. Echocardiography showed improved cardiac function, evidenced by the reduced left ventricular end-diastolic dimension and left ventricular end-systolic dimension, and the increased ejection fraction and fractional shortening in ZAC-treated animals (all P

This study aimed at exploring the active components and mechanisms of Jinhua Qinggan granules (JQG) in the prevention and treatment of coronavirus disease 2019 (COVID-19) using network pharmacology and molecular docking technology. These efforts were accomplished by employing the holistic approach of traditional Chinese medicine (TCM) and considering the virus-host interaction consisting of viral characteristics, the entry pathway into the host, and the resulting immune response. The chemical constituents and molecular targets of the 12 herbs from JQG were obtained using the TCM Systems Pharmacology database and analysis platform. UniProt was used to search for genes corresponding to JQG protein targets and Cytoscape 3.7.2 to construct the component-target (gene) network. Database for Annotation, Visualization and Integrated Discovery was used to perform enrichment analysis of gene ontology functions and the Kyoto Encyclopedia of Genes and Genomes pathways to predict the mechanism of action. The components ranked high in the network, and the major active components of the principal medicines, based on published literature, were docked with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 3CL hydrolase, SARS-CoV-2 spike glycoprotein (S protein), angiotensin conversion enzyme II (ACE2), and suppressor of cytokine signaling 1 (SOCS1). Visualization analysis demonstrated that the core active components of JQG had a strong affinity for SARS-CoV-2 3CL hydrolase, SARS-CoV-2 S protein, ACE2, and SOCS1. These data imply that the potential active components of JQG may act on multiple signaling pathways by binding to targets such as SARS-CoV-2 3CL hydrolase, S protein, ACE2, and SOCS1, thereby inhibiting virus replication and targeting cell binding, reducing host inflammation, and activating antiviral immunity to a certain extent.

Highlights SnO2-Co-carbon nanocomposites were in-situ prepared from Co-based metal–organic frameworks and showed a remarkably high initial Coulombic efficiency (82.2%) and a capacity of ~ 800 mAh g−1 at a high current density of 5 A g−1.Facile approach for designing highly reversible and stable electrodes for next-generation high-performance lithium-ion batteries. Electronic supplementary material The online version of this article (10.1007/s40820-019-0246-4) contains supplementary material, which is available to authorized users., The two major limitations in the application of SnO2 for lithium-ion battery (LIB) anodes are the large volume variations of SnO2 during repeated lithiation/delithiation processes and a large irreversible capacity loss during the first cycle, which can lead to a rapid capacity fade and unsatisfactory initial Coulombic efficiency (ICE). To overcome these limitations, we developed composites of ultrafine SnO2 nanoparticles and in situ formed Co(CoSn) nanocrystals embedded in an N-doped carbon matrix using a Co-based metal–organic framework (ZIF-67). The formed Co additives and structural advantages of the carbon-confined SnO2/Co nanocomposite effectively inhibited Sn coarsening in the lithiated SnO2 and mitigated its structural degradation while facilitating fast electronic transport and facile ionic diffusion. As a result, the electrodes demonstrated high ICE (82.2%), outstanding rate capability (~ 800 mAh g−1 at a high current density of 5 A g−1), and long-term cycling stability (~ 760 mAh g−1 after 400 cycles at a current density of 0.5 A g−1). This study will be helpful in developing high-performance Si (Sn)-based oxide, Sn/Sb-based sulfide, or selenide electrodes for LIBs. In addition, some metal organic frameworks similar to ZIF-67 can also be used as composite templates. Electronic supplementary material The online version of this article (10.1007/s40820-019-0246-4) contains supplementary material, which is available to authorized users.

One known bis-indole alkaloid-voacamine was isolated from

The relative stabilities of different chemical arrangements of Pd-Ir and Au-Rh nanoalloys (and their pure metal equivalents) are studied, for a range of compositions, for fcc truncated octahedral 38- and 79-atom nanoparticles (NPs). For the 38-atom NPs, comparisons are made of pure and alloy NPs supported on a TiO2(110) slab. The relative energies of different chemical arrangements are found to be similar for Pd-Ir and Au-Rh nanoalloys, and depend on the cohesive and surface energies of the component metals. For supported nanoalloys on TiO2, the interaction with the surface is greater for Ir (Rh) than Pd (Au): most of the pure NPs and nanoalloys preferentially bind to the TiO2 surface in an edge-on configuration. When Au-Rh nanoalloys are bound to the surface through Au, the surface binding strength is lower than for the pure Au NP, while the Pd-surface interaction is found to be greater for Pd-Ir nanoalloys than for the pure Pd NP. However, alloying leads to very little difference in Ir-surface and Rh-surface binding strength. Comparing the relative stabilities of the TiO2-supported NPs, the results for Pd-Ir and Au-Rh nanoalloys are the same: supported Janus NPs, whose Ir (Rh) atoms bind to the TiO2 surface, bind most strongly to the surface, becoming closer in energy to the core-shell configurations (Ir@Pd and Rh@Au) which are favoured for the free particles.

For multiobjective optimization problems, different optimization variables have different influences on objectives, which implies that attention should be paid to the variables according to their sensitivity. However, previous optimization studies have not considered the variables sensitivity or conducted sensitivity analysis independent of optimization. In this paper, an integrated algorithm is proposed, which combines the optimization method SPEA (Strength Pareto Evolutionary Algorithm) with the sensitivity analysis method SRCC (Spearman Rank Correlation Coefficient). In the proposed algorithm, the optimization variables are worked as samples of sensitivity analysis, and the consequent sensitivity result is used to guide the optimization process by changing the evolutionary parameters. Three cases including a mathematical problem, an airship envelope optimization, and a truss topology optimization are used to demonstrate the computational efficiency of the integrated algorithm. The results showed that this algorithm is able to simultaneously achieve parameter sensitivity and a well-distributed Pareto optimal set, without increasing the computational time greatly in comparison with the SPEA method.

The microvillar localization of Na+-H+ exchanger regulatory factor (NHERF)1/2 requires not only ezrin, radixin and moesin (ERM)-binding domain (EBD) but also a newly defined ERM-binding regulatory sequence (EBRS) that modulates NHERF1/2–ezrin binding. NHERF2 EBRS is also regulated by phosphorylation, which affects NHE3 (Na+-H+ exchanger 3) stimulation by dexamethasone., In the brush border of intestinal and kidney epithelial cells, scaffolding proteins ezrin, Na+-H+ exchanger regulatory factor (NHERF)1 and NHERF2 play important roles in linking transmembrane proteins to the cytoskeleton and assembling signalling regulatory complexes. The last 30 carboxyl residues of NHERF1 and NHERF2 form the EBDs [ezrin, radixin and moesin (ERM)-binding domain]. The current study found that NHERF1/2 contain an ERM-binding regulatory sequence (EBRS), which facilitates the interaction between the EBD and ezrin. The EBRSs are located within 24 and 19 residues immediately upstream of EBDs for NHERF1 and NHERF2 respectively. In OK (opossum kidney) epithelial cells, EBRSs are necessary along with the EBD to distribute NHERF1 and NHERF2 exclusively to the apical domain. Furthermore, phosphorylation of Ser303 located in the EBRS of NHERF2, decreases the binding affinity for ezrin, dislocates apical NHERF2 into the cytosol and increases the NHERF2 microvillar mobility rate. Moreover, increased phosphorylation of Ser303 was functionally significant preventing acute stimulation of NHE3 (Na+-H+ exchanger 3) activity by dexamethasone.

Genetic determinants appear to play a role in susceptibility to chronic diarrhea, but the genetic abnormalities involved have only been identified in a few conditions. The Na+/H+exchanger 3 (NHE3) accounts for a large fraction of physiologic intestinal Na+absorption. It is highly regulated through effects on its intracellular COOH-terminal regulatory domain. The impact of genetic variation in the NHE3 gene, such as single nucleotide polymorphisms (SNPs), on transporter activity remains unexplored. From a total of 458 SNPs identified in the entire NHE3 gene, we identified three nonsynonymous mutations (R474Q, V567M, and R799C), which were all in the protein's intracellular COOH-terminal domain. Here we evaluated whether these SNPs affect NHE3 activity by expressing them in a mammalian cell line that is null for all plasma membrane NHEs. These variants significantly reduced basal NHE3 transporter activity through a reduction in intrinsic NHE3 function in variant R474Q, abnormal trafficking in variant V567M, or defects in both intrinsic NHE3 function and trafficking in variant R799C. In addition, variants NHE3 R474Q and R799C failed to respond to acute dexamethasone stimulation, suggesting cells with these mutant proteins might be defective in NHE3 function during postprandial stimulation and perhaps under stressful conditions. Finally, variant R474Q was shown to exhibit an aberrant interaction with calcineurin B homologous protein (CHP), an NHE3 regulatory protein required for basal NHE3 activity. Taken together, these results demonstrate decreased transport activity in three SNPs of NHE3 and provide mechanistic insight into how these SNPs impact NHE3 function.