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The role of the glioblastoma (GBM) microenvironment is pivotal in the development of gliomas. Discovering drugs that can traverse the blood-brain barrier and modulate the tumor microenvironment is crucial for the treatment of GBM. Dioscin, a steroidal saponin derived from various kinds of plants and herbs known to penetrate the blood-brain barrier, has shown its powerful anti-tumor activity. However, little is known about its effects on GBM microenvironment. Bioinformatics analysis was conducted to assess the link between GBM patients and their prognosis. Multiple techniques, including RNA sequencing, immunofluorescence staining, Western blot analysis, RNA-immunoprecipitation (RIP) assays, and Chromatin immunoprecipitation (CHIP) analysis were employed to elucidate the mechanism through which Dioscin modulates the immune microenvironment. Dioscin significantly impaired the polarization of macrophages into the M2 phenotype and enhanced the phagocytic ability of macrophages in vitro and in vivo. A strong correlation between high expression of RBM47 in GBM and a detrimental prognosis for patients was demonstrated. RNA-sequencing analysis revealed an association between RBM47 and the immune response. The inhibition of RBM47 significantly impaired the recruitment and polarization of macrophages into the M2 phenotype and enhanced the phagocytic ability of macrophages. Moreover, RBM47 could stabilize the mRNA of inflammatory genes and enhance the expression of these genes by activating the NF-κB pathway. In addition, NF-κB acts as a transcription factor that enhances the transcriptional activity of RBM47. Notably, we found that Dioscin could significantly inhibit the activation of NF-κB and then downregulate the expression of RBM47 and inflammatory genes protein. Our study reveals that the positive feedback loop between RBM47 and NF-κB could promote immunosuppressive microenvironment in GBM. Dioscin effectively inhibits M2 polarization in GBM by disrupting the positive feedback loop between RBM47 and NF-κB, indicating its potential therapeutic effects in GBM treatment. [ABSTRACT FROM AUTHOR]

The selective catalytic reduction of nitrogen oxides by methane (CH 4 /NO X -SCR) is a potential technique for the abatement of the NO X emissions from lean-burn GDI engines, due to the excellent thermal stability of CH 4. This work focuses on the promotion of In/SSZ-13 catalysts by Ce modification for the CH 4 /NO X -SCR performance at high temperatures. A series of In/SSZ-13 and Ce-In/SSZ-13 catalysts were prepared using the wetness impregnation method. The effects of Ce modification on the catalytic performance were analysed in detail using the scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflectance spectrum and temperature-programmed desorption/reduction techniques. The results show that the Ce modification significantly enhances the high-temperature activity of the In/SSZ-13 catalysts for the NO X -SCR reaction, especially for the 5 wt% Ce-15 wt% In/SSZ-13 sample which has more than 75% NO X conversion at 390–700 °C. In addition, the Ce modification enhances the water vapor tolerance of the catalyst sample. The Ce modification increases not only the concentration of surface chemisorption oxygen species, but also the relative amount of InO+ species which serve as the main active sites for CH 4 activation. Furthermore, the incorporation of Ce into In/SSZ-13 greatly promotes NO X adsorption on the catalyst surface. Most importantly, the Ce modification makes In species well-dispersed on the catalyst surface and thus suppresses the formation of bulk In 2 O 3 species which are more active for the CH 4 non-selective oxidation. The combination of all these effects results in the Ce-In/SSZ-13 samples with the superior catalytic activity. • The high-temperature activity of In/SSZ-13 for CH 4 /NO X -SCR is enhanced by Ce. • The 5% Ce −15% In/SSZ-13 catalyst has more than 75% NO X conversion at 390-700 °C. • Ce modification increases the concentration of surface chemisorption oxygen species. • The incorporation of Ce promotes the concentration of InO+ species. • Ce modification suppresses the formation of bulk In 2 O 3. [ABSTRACT FROM AUTHOR]

The properties and oxidation of in-cylinder soot from a diesel engine fueled with n -heptane were explored under the simulated exhaust gas recirculation (EGR) condition, via CO 2 addition to the intake air of the engine. A self-developed total cylinder sampling system was employed to obtain the soot samples at the EGR ratios of 0 and 25%, and this study only focused on the soot oxidation that occurred in the soot oxidation-dominated (SOD) phase. Computational fluid dynamics (CFD) simulations were performed to determine the local combustion characteristics related to soot oxidation. Soot oxidation rates were evaluated based on in-cylinder soot mass traces and CFD results. Soot properties were characterized in terms of nanostructure, carbon chemical state, and surface functional groups. Detailed analysis of the soot mass indicates that EGR addition enhances the mass-based specific rate of soot oxidation. However, CFD results show that EGR addition reduces the flame temperature and the concentrations of O 2 and OH, and consequently decreases soot surface oxidation rates by O 2 and by OH. The characterization of soot properties shows that EGR decreases the degree of structural ordering and results in the formation of more oxygenated and aliphatic C–H groups on the soot surface. This alteration in physico-chemical properties favors soot oxidation during the combustion process, and results in an increase in the mass-based specific rate of soot oxidation in the SOD phase. [ABSTRACT FROM AUTHOR]

Abstract Post injection has significant benefit in the reduction of diesel soot emissions. Therefore, there is a need to understand the effect of post-injection strategy on soot physicochemical properties and reactivity because they play an important role in soot oxidation process that governs the final soot emissions. This work focuses on the impact of post injection on the physicochemical properties and reactivity of diesel in-cylinder soot using a main plus post injection (M*P) and a single injection (M) strategy. The soot was sampled by a developed total cylinder sampling system, and the dividing points of soot formation-dominant and oxidation-dominant phases were used for studying the impacts of post injection on the characteristics of in-cylinder soot. The physicochemical properties of the soot samples, including primary particle size, nanostructure, carbon chemical state and surface functional groups, were characterized. The soot reactivity was evaluated in terms of peak temperature, burnout temperature and apparent activation energy. In the oxidation-dominant phase, the M*P soot initially possesses smaller primary particle size, shorter fringe length, larger tortuosity, lower sp2/sp3 hybridization ratio of carbon atoms and higher content of aliphatic C H groups than the M soot. The beneficial influence of physicochemical properties on soot reactivity when using post injection is validated by the thermogravimetric data, which shows that the M*P soot is more reactive than the M soot at the onset of the oxidation-dominant phase. In the M*P case, the soot generated from the main-injection combustion has lower reactivity than the soot from the post-injection combustion after they experience the soot formation-dominant phase. The results indicate that the use of post injection leads to in-cylinder soot with physicochemical properties that favor reactivity. The enhancement of reactivity means that the soot will be more readily oxidized in the subsequent combustion process, and consequently contributes to a reduction in final soot emissions. [ABSTRACT FROM AUTHOR]

Abstract In this study, we investigated the redox reaction between a hydrocarbon (HC) and adsorbed NO x over Cu Pt Ba/Al 2 O 3 lean NO x trap (LNT) catalyst. Experimental characterizations included temperature-programmed desorption (TPD), temperature-programmed reduction (TPR), in situ diffuse reflectance Fourier transform spectroscopy (in situ DRIFTs) and Raman spectroscopy. Density functional theory (DFT) calculations were also performed. The model C 3 H 6 first adsorbed to the catalyst surface, and the resulting C 3 H 6 -adsorbed species reacted with adsorbed NO x species to form various intermediates such as: carboxylates, enolic compounds, carbonato complexes, Pt-carbonyls, acid anhydrides, basic hydroxyls, nitrogen-containing organic species, acyl chlorides, and ammonium salts. These intermediates participated in subsequent reactions and finally produced the effluent gases CO 2 , N 2 , NH 3 , and H 2 O. The decomposition ability of adsorbed NO x species indicated that the NO x species participated in the C 3 H 6 oxidation in the order: adsorbed N 2 O 4 > monodentate nitrates > free ionic nitrates > bulk free ionic nitrates. Carbonaceous materials were generated during the C 3 H 6 oxidation process and were consumed as intermediates by gaseous NO x released upon decomposition of the adsorbed NO x species. In summary, the redox reaction between C 3 H 6 and adsorbed NO x followed the Langmuir–Hinshelwood mechanism, and three reaction routes were proposed for the redox process over the studied catalyst. The activation energy barriers determined by DFT + U calculations for the three routes indicated that the initial dissociation of NO 3 − species in R (2) occurred more easily than the oxidation of C 3 H 6 species in R (1) , delivering the active oxygen species that participated in R (1) and R (3). As the reactions proceeded, the higher energy barrier for the complete dissociation of NO 2 * indicated that the temperature determined the further decomposition of adsorbed NO x species, and R (1) and R (3) were constrained owing to the limited surface active oxygen species from R (2). [ABSTRACT FROM AUTHOR]

Metastasis and recurrence severely impact the treatment effect of hepatocellular carcinoma (HCC). HCC complicated with cholestasis is more prone to recurrence and metastasis. Previous studies have implicated pathogenesis of HCC by bile acid; however, the underlying mechanism is unknown yet. Glycochenodeoxycholate (GCDC) is one of most important component of bile acid (BA). In the present study, the role of GCDC in HCC cells invasion was detected by in vitro and in vivo assays. GCDC was found to significantly enhance the invasive potential of HCC cells; Further studies showed that GCDC could induce autophagy activation and higher invasive capability in HCC cells. Interestingly, inhibition of autophagy by chloroquine (CQ) reversed this phenomenon. Subsequently, the correlation between TBA expression level and clinicopathological characteristics was analyzed in HCC patients. Clinically, high TBA level in HCC tissue was found to be associated with more invasive and poor survival in HCC patients. Mechanistic study showed that bile acid induced autophagy by targeting the AMPK/mTOR pathway in HCC cells. Therefore, our results suggest that bile acid may promote HCC invasion via activation of autophagy and the level of bile acid may serve as a potential useful indicator for prognosis of HCC patients. • GCDC enhanced the metastasis of HCC which was mediated by autophagy. • AMPK/mTOR pathway contributed to the metastatic potential of HCC cells mediated by autophagy. • TBA level was correlated to autophagy activation and HCC prognosis in clinically specimens. [ABSTRACT FROM AUTHOR]

Abstract This paper studies the electrical properties of the soot particles generated from an n-heptane inverse diffusion flame and the relationship between the electrical properties and the nanostructure. The electrical conductivity of isolated soot particle and work function of soot particles were measured by a PeakForce tunneling atomic force microscopy and a Kelvin-probe force microscopy. The nanostructure of soot particles was evaluated using X-ray diffraction and X-ray photoelectron spectroscopy. Different electrical conductivity distributions were found as the soot particles gradually matured, and at the same time the mean electrical conductivity of soot particles exhibited a nearly exponential increase. There existed a percolation threshold at which the mean electrical conductivity sharply increased by approximately two orders of magnitude. Similarly, the work function of soot particles increased during soot maturation process, which implies that it becomes harder for the electrons to escape from the soot samples. The crystallite width had a positive correlation with the logarithm of electrical conductivity and the work function for soot particles, while the interlayer spacing presented a negative correlation with the logarithm of electrical conductivity and work function. These results suggest that the electrical conductivity and work function can serve as indicators of ordering degree of soot particles. Moreover, the dependence of electrical properties on the nanostructure demonstrates the potential of better controlled flame conditions for producing tailored soot particles for a variety of applications. [ABSTRACT FROM AUTHOR]

Abstract Aim Spinal cord injury (SCI) causes increased apoptosis of neurons, leading to irreversible dysfunction of the spinal cord. In this study, we investigated the effects of the progression of SCI and potential regulation of apoptosis after the Pleckstrin homology (PH) domain and leucine rich repeat protein phosphatase 1 ( PHLPP1 ) gene was silenced. Main methods Spinal cord injection, and neuronal transfection with a recombinant adenovirus vector encoding small interfering RNA (siRNA) against PHLPP1 (AdsiPHLPP1) successfully silenced PHLPP1. These created in vivo and in vitro PHLPP1-silenced models, respectively, resulting in stable expression of the transgene in neurons. Key findings The results showed that silencing of PHLPP1 evidently reduced levels of the nuclear factor erythroid 2-related factor 2 (Nrf2) after SCI. Western blot analysis revealed that the mice injected with AdsiPHLPP1 showed increased the expression of pro-apoptotic factors (Bax and cleaved-caspase 3), and reduced levels of neurotrophic (BDNF) and anti-apoptotic (Bcl-2) factors, both in vivo and in vitro. The motor function of AdsiPHLPP1-injected mice was restored more slowly than that of wild type (WT) mice. In addition, the number of motor neurons surviving in the anterior horn of the spinal cord was also reduced after SCI. Significance Our results confirm that silencing of PHLPP1 promotes neuronal apoptosis and inhibits functional recovery after injury in vivo and in vitro. Consequently, PHLPP1 represents a potential therapeutic target gene for the clinical treatment of SCI. [ABSTRACT FROM AUTHOR]

GLP-1 signaling pathway has been well studied for its role in regulating glucose homeostasis, as well as its beneficial effects in energy and nutrient metabolism. A number of drugs based on GLP-1 have been used to treat type 2 diabetes mellitus. GLP-1R is expressed in multiple organs and numerous experimental studies have demonstrated that GLP-1 signaling pathway exhibits pro-survival functions in various disorders. In the central nervous system, stimulation of GLP-1R produces neuroprotective effects in specific neurodegenerative disorders, such as Alzheimer’s disease and Parkinson’s disease. The preproglucagon neurons located in the brainstem can also produce GLP-1. GLP-1 analogs have a long-acting effect and are able to pass the blood-brain barrier, which probably extends the therapeutic efficacy of GLP-1R activation. Neurodegenerative or traumatic conditions can damage the spinal cord and result in motor and sensory dysfunction. Evidence supports that GLP-1R activation in the spinal cord possesses beneficial effects and significant therapeutic potential. Herein, we review studies that have focused on GLP-1 and the spinal cord, and summarize the expression of GLP-1R and the innervation of PPG neurons in the spinal cord, as well as the potential therapeutic benefits of GLP-1R activation. [ABSTRACT FROM AUTHOR]

Vitamin D plays a major role primarily in bone mineral homeostasis; however, the action of vitamin D on male reproduction of boars remains unknown. This study was conducted to evaluate the effects of dietary vitamin D 3 supplementation on reproductive performance of boars. Twenty-four Yorkshire boars with eighteen months were randomly allocated to one of three vitamin D 3 levels diets: 200 IU/kg (C), 2000 IU/kg (T1) and 4000 IU/kg (T2) of vitamin D 3 for a 16-week period. Results showed that sperm motility, effective sperm number per ejaculate, acrosome intactness ratio, and membrane intactness ratio in T1 group were significantly higher than those in C group. The sperm membrane intactness ratio was higher in T1 group than in T2 group, whereas the deformity ratio was significantly lower in T1 than in C and T2 groups. Dietary supplementation with vitamin D 3 significantly increased 25-OHD 3 concentration in the blood and seminal plasma, but there was no significant difference in its concentration in the seminal plasma between T1 and T2 groups. The concentrations of blood testosterone and aromatase activity increased following vitamin D supplementation. Seminal plasma Ca 2+ , fructose concentration, and acid phosphatase activity were higher in T1 group than in C group, but not significantly different from the corresponding values in T2 group. Furthermore, expression of CYP19, CYP24A1, and VDR mRNAs in sperm was up-regulated in T1 group compared to that in C group. In conclusion, supplementation of boar diets with 2000 IU/kg vitamin D 3 increased the sperm motility and effective sperm number, which was in line with the elevated concentrations of vitamin D, hormone secretion and gene expression. [ABSTRACT FROM AUTHOR]

[Display omitted] • A mechanism-informed phenotypic screening guides lead optimization. • The structural simplification approach identifies a 4-phenoxy-quinoline-based hit. • Lead compound disables AURKB by disrupting its mitotic localization. • Lead compound elicits cytotoxicity in diverse cancer cell lines at low nM concentrations. We combined a mechanism-informed phenotypic screening (MIPS) assay with a structural simplification strategy to guide the discovery of compounds that disrupt the localization of the mitotic regulator, Aurora kinase B (AURKB), rather than inhibiting its catalytic activity. An initial hit 4-(4-methylthiophen-2-yl)-N-(4-(quinolin-4-yloxy)phenyl)phthalazin-1-amine was identified after screening an in-house library of small molecules and phenocopied the loss of function mutations in AURKB without inhibiting its catalytic activity. We isolated this hit compound activity to its 4-phenoxy-quinoline moiety. The fragment was further optimized into a class of new chemical entities that potently disrupt the mitotic localization of AURKB at low nanomolar concentrations and consequently elicit severe growth inhibition in diverse human cancer cell lines. A lead compound, N-(3-methoxy-5-(6-methoxyquinolin-4-yl)oxy)phenyl)acetamide possessed desirable pharmacokinetic properties such as AUC 0-∞ : 227.15 [ng∙h/mL/(mg/kg)]; C max : 3378.52 ng/mL T 1/2 : 3.52 h; and F%: 42 % and produced the AURKB-inhibitory phenotypes in a mouse xenograft model. A lead compound is a powerful tool for interrogating the regulation of AURKB and has the potential to be further developed as a first-in-class oncology therapeutic. [ABSTRACT FROM AUTHOR]

Activity-based drug screens have successfully led to the development of various inhibitors of the catalytic activity of aurora kinases (AURKs), major regulatory kinases of cell division. Disrupting the localization of AURKB, rather than its catalytic activity, represents a largely unexplored alternative approach to disabling AURKB-dependent processes. Localization disruptors could be just as specific as direct inhibitors of AURKB activity, may bypass their off-target and select on-target toxicities, and are likely less susceptible to drug resistance resulting from mutations of the AURKB catalytic site. In this study, we demonstrate that the pan-AURK inhibitor AMG900 works at a low concentration not by inhibiting the phosphorylation of H3 at Ser10, an AURKB substrate, but by disrupting the mitotic localization of AURKB. Structural deletion studies pinpoint this undescribed activity to the 2-phenoxy-3,4′-bipyridine moiety of AMG900. Guided by a mechanism-informed phenotypic screening (MIPS) assay, the drug fragment is optimized into a novel class of inhibitors that, at low nanomolar concentrations, can disable AURKB through disruption of its mitotic localization and have desirable oral PK properties. Hierarchical clustering of cell fitness profiles reveals that these compounds cluster with each other, rather than with known AURK inhibitors such as AMG900 and VX-680. Validation studies in mice demonstrate that compound 15a elicits mitotic arrest and apoptosis in NCI–H23 human lung adenocarcinoma xenografts, resulting in a pronounced suppression of tumor growth. The discovery and optimization of compounds that disrupt AURKB localization are successfully facilitated by MIPS. Our findings suggest that 2-phenoxy-3, 4′-bipyridine derivatives have the potential to be further developed as effective therapeutics for the treatment of malignancy by delocalizing AURKB. [Display omitted] • Mechanism-informed phenotype approach to guide lead optimization. • Structural simplification to identify 2-phenoxy-3,4′-bipyridine moiety of AMG900. • Lead compound 15a disables AURKB by disrupting its mitotic localization. • 15a elicits broad spectrum cytotoxicity at low nM concentrations. [ABSTRACT FROM AUTHOR]

Allied to the extensive use of online shopping, product recommendation on websites is vitally important for E-commerce. Consequently, collaborative filtering and content-based filtering have been widely used in recommendation systems on E-commerce websites. However, these filtering methods have many problems, such as cold start, prejudiced ratings and inaccurate suggestions. To generate valid and accurate suggestions, researchers have proposed integrating semantic features of the data in an ontology into the recommendation process. However, most existing studies only include the type and features of a product without considering the relational characteristics thereof. Given that the relational characteristics can provide much useful information during the recommendation process, we have designed an easily realizable recommendation system framework based on relational data by integrating the relational data in the domain ontology and applying a genetic algorithm to process the recommendation. Experimental results show that there are obvious improvements in the methods for dealing with sparsity and cold start problems as well as the accuracy and timeliness of recommendations. [ABSTRACT FROM AUTHOR]

The mechanism for the hydrogen abstraction reaction C 2 H 3 + CH 3 CHO has been investigated by the CCSD(T)/cc-pVTZ method based on the geometries of stationary points optimized at the B3LYP/6-311++G(d,p) level of theory. Two abstraction channels have been identified for the production of C 2 H 4 + CH 2 CHO and C 2 H 4 + CH 3 CO. The potential barrier heights of the corresponding transition states TSR/P1 and TSR/P2 were predicted to be 9.47 and 5.95 kcal/mol at the CCSD(T)//B3LYP level of theory, respectively. The rate constants and branching ratios for the two H-abstraction channels were calculated using conventional transition state theory with Eckart tunneling correction at the temperature range 300–2500 K. The predicted rate constants have been compared with available literature data. Both the forward and reverse rate constants have positive temperature dependence and the tunneling effect is only important at low temperatures. The branching ratio calculation shows that the channel producing C 2 H 4 + CH 3 CO remains predominant throughout the entire studied temperature range. [ABSTRACT FROM AUTHOR]

Abstract: Responsible for orchestrating cellular energy production, mitochondria are central to the maintenance of life and the gatekeepers of cell death. Its morphology is dynamic and controlled by continual and balanced fission and fusion events. In this study, we analyzed the mitochondrial dynamics and functions after spinal cord injury in rats and further to discuss the mechanisms of the mitochondria regulated cell injury during SCI. Using adult rat spinal cord injury model, it was found that the absolute number of mitochondria per area was significantly less and the individual mitochondrial cross-sectional area was significantly greater in the neurons of rats in SCI group than in the sham-operated group at 3h and 6h after SCI, and the reverse pattern at 12h and 24h after SCI. The results from Western blot and RT-PCR assays showed that the protein and mRNA levels of mitochondrial fusion-related genes (Mfn1 and Mfn2) decreased and fission-related genes (Drp1 and Fis1) increased at 3h and 6h after SCI. At 12h and 24h after SCI the reverse pattern of Mfn1, Mfn2, Drp1 and Fis1 expression was found. Taken together the results of the present study showed the mitochondrial tendency of elongation and fusion in the injured spinal cord at 3h and 6h after SCI, and the tendency of mitochondrial fission at 12h and 24h after SCI in our SCI models of rat. These findings have important implications for our understanding of the mechanisms of mitochondrial dynamics and functions after SCI injury. And mitochondrial fusion may potentially be used as a target for improving spinal cord function in the first 6h after SCI. Mitochondrial fusion may be inhibited at 12–24h after SCI for improving functional outcomes following SCI. [Copyright &y& Elsevier]

Abstract: Manganese–zirconium catalysts loaded on ZSM-5 (Si/Al=25) were prepared using an ion-exchange method and investigated for the selective catalytic reduction of NO, with the aim of studying the effects of zirconium doping on the performance of Mn-based ZSM-5 catalysts. A series of characterization techniques, namely N2-sorption, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM), temperature-programmed reduction by hydrogen, and X-ray photoelectron spectroscopy (XPS), were used to characterize these samples. TEM and XRD results showed that the addition of zirconium increased the manganese dispersion and prevented manganese crystallization. XPS results demonstrated that the introduction of zirconium enhanced the manganese species enrichment on the ZSM-5 grain surfaces. After zirconium addition, some of the manganese ions were incorporated into the zirconia lattice. The strong interaction between Mn and Zr contributed to the formation of Zr3+ ions or oxygen vacancies around the Zr4+ ions, which enhanced the redox abilities of the Mn–Zr/ZSM-5 catalysts. The temperature range for efficient NO conversion was lowered after zirconium doping. The MnZr3/ZSM-5 (Mn 3.2wt.% and Zr 8.6wt.%) sample exhibited NO x conversions (>90%) over a wide temperature range (230–415°C) and markedly superior to that of Mn/ZSM-5 (296–425°C). Moreover, the formation of N2O was suppressed at low temperatures due to the presence of zirconium in the catalysts. [Copyright &y& Elsevier]

Abstract: This paper reports the characteristics of surface functional groups (SFGs) and oxidation reactivity of in-cylinder soot during the diesel combustion process and discusses the correlation between SFGs and the oxidation reactivity of soot. Test soot samples were obtained from a total cylinder sampling system. SFGs and the apparent activation energy for the soot oxidation were determined by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and thermogravimetric analysis. Results reveal that the concentrations of aliphatic C–H, C–OH and Care dependent on the combustion stages. The ratio of aromatic Chatic C–H groups rapidly increases in the premixed combustion phase, indicating significant loss of aliphatic C–H groups from the soot surface. As the combustion proceeds, the ratio of the two groups gradually increases, following an earlier drop during the diffusion combustion phase. In contrast, the concentration of both C–OH and Cshows a bimodal distribution during the combustion process, with the concentrations peaking in the premixed and diffusion combustion stages, respectively. The apparent activation energies for the oxidation of soot collected under the applied engine operating conditions are observed in the range of 122.12–158.2kJmol−1 at various crank angles, revealing a similar variation to that of aliphatic C–H groups. Aliphatic C–H groups are a more important factor in governing soot oxidation reactivity than the oxygenated SFGs. [Copyright &y& Elsevier]

Abstract: Zirconium doped Cu/ZSM-5 catalysts were prepared and characterized in this investigation. Catalytic activity during soot combustion was determined in both O2/He and NO/O2/He atmospheres by temperature-programmed oxidation. The use of zirconium reduces the temperature of maximum soot oxidation rate by 229°C in O2/He atmosphere and 270°C in NO/O2/He atmosphere. The promoting effect of zirconium is discussed in terms of surface dispersion, enrichment of active components, and creation of oxygen vacancies where molecular oxygen or NO x is adsorbed forming basic surface oxygen species active for soot oxidation. The NO2 formed at the copper–zirconium interface sites leads to the ignition temperature being significantly decreased to 93°C, which is inside the exhaust temperature range of diesel engines. To understand the combustion reaction kinetics, the activation energy and reaction order of soot combustion were evaluated. According to the Redhead method, the activation energy for non-catalyzed reaction is 164kJ/mol under the O2/He atmosphere. For the Cu/ZSM-5 and Cu–Zr/ZSM-5, the activation energies under the O2/He atmosphere (134–151kJ/mol) are slightly higher than those under the NO/O2/He atmosphere (128–135kJ/mol). The Freeman–Carroll method is suitable to describe the soot combustion in the NO/O2/He atmosphere, with the activation energies for the catalysts in the range of 97–112kJ/mol and the average value of reaction order equal to 1.36. [Copyright &y& Elsevier]

Abstract: A general sonochemical approach that allows for a facile, rapid synthesis of MSn(OH)6 (M=Ba, Ca, Sr) one-dimension (1D) nanostructures has been developed. The resulting CaSn(OH)6 products possessed a nanotubular structure while SrSn(OH)6 and BaSn(OH)6 showed nanowire-like structures. The as-synthesized MSn(OH)6 products were characterized by XRD, SEM and TEM techniques. Owing that BaSn(OH)6 nanowires, CaSn(OH)6 nanotubes, and SrSn(OH)6 nanowires takes different crystal structures respectively, they share different growth mechanisms. However, we found that in all three growing processes, both ultrasound irradiation and the presence of Na2CO3 in the synthetic procedure had an significant impact on the homogeneous nucleation and fast growth of 1D MSn(OH)6 nanostructures. This approach represents a successful example for the fast construction of innovative inorganic nanostructures in the absence of any surfactants. [Copyright &y& Elsevier]

Abstract: The interacting patterns and mechanism of the binding affinity between the local anaesthetic procaine and four DNA bases (adenine, cytosine, guanine and thymine) in neutral form have been investigated in gas phase using the Austin Model l and density functional methods. The results show that the complexes are mainly stabilized by the H-bonding interactions. The bond critical point properties of the optimized complexes were analyzed by using the atoms in molecules theory with DFT method and the results show that the presence of the C−H···O or C−H···N hydrogen bonding. The natural bond orbital analysis was performed to quantitatively evaluate the hydrogen bonding interaction. The interacting energy shows that the binding of procaine with guanine is the most strong, whereas its binding to cytosine exhibits relatively weaker stability. The strength order of the relevant transferred charge between procaine and DNA base with natural population analysis are consist with the HOMO–LUMO gap results for each complex. And the order is accord with the relevant electrochemical experimental results. [Copyright &y& Elsevier]

Abstract: The interaction between small gold clusters and thymine was studied using density functional method (DFT). Geometries of neutral thymine with Au n (n =2–4) clusters were optimized using the B3LYP method. The 6-31G+(d,p) basis set was used for thymine and the Stuttgart/Dresden effective core potential (ECP) basis set SDD was employed for the gold atom. Structural parameters and energy properties were discussed for the optimized complexes stabilized with the Aung bond and the nonconventional Au···Hn bond. The calculated interacting energy results show that the binding of Au n is the most strong at thymine (H1,O2) site, whereas its binding at (H3,O2) displays relatively weaker stability. Furthermore, analysis of the charge distributions of the optimized complexes by using the natural bond orbital analysis indicates charge is transferred from the lone pair of oxygen in thymine to the n* and σ* orbitals of Au during the interaction. The calculated second-order perturbation stabilization energies show that the Aung bond plays an important role in forming the Au n ·Thymine complexes. [Copyright &y& Elsevier]

• The oscillation frequencies of an edge skyrmion in circular nano-pillars are analytically derived. • The size of the sample to produce isolated edge skyrmion oscillation is relatively small. • The oscillation frequencies strongly depend on the eccentricity and the perimeter of the elliptical nanopillar. The magnetic skyrmions have received a lot of attention because they have potential applications in spin torque nano-oscillators. In this paper, we numerically and analytically study the dynamics of edge skyrmions in circular nano-pillar oscillators with perpendicular magnetic anisotropy (PMA) free layer and spin polarizer. Numerical simulations demonstrate that a steady edge skyrmion oscillation mode with GHz frequency can be driven by spin currents and magnetic fields. The oscillation frequencies in circular nano-pillars with different radius are analytically derived, which agrees well with the numerical results. In addition, the steady oscillations of edge skyrmions are also observed in elliptical nano-pillars, in which the oscillation frequencies strongly depend on the eccentricity and perimeter of the elliptical nanopillar. It is found that the oscillation frequency of this edge skyrmion can range from 1 GHz to 6.7 GHz. The line width is about 55 MHz. [ABSTRACT FROM AUTHOR]

In this study, cable-stiffened steel columns (CSSCs), which primarily aim to enhance compression behaviour, were experimentally investigated. In contrast to other stiffened column types, the cable-stiffened steel columns investigated in this work were equipped with a three-branch crossarm system. A series of tests were performed on 2.4 m CSSCs with two different crossarm–main column connection types (i.e., rigid and scissor types). In addition to the connection types, the effects of crossarm length and initial pretension on the load carrying capacities of CSSCs were also studied experimentally. The experimental results indicate that the three-branch crossarm system is effective in improving the buckling load of ordinary compression columns. The findings prove that the scissor-type connections between the crossarms and the main column could also be used in practical applications. Moreover, a unique, asymmetric post-buckling mode for a CSSC with a three-branch crossarm system was observed. The effects of crossarm length and pretension in cables are also demonstrated. This results presented in this work could be of assistance in the further design of CSSCs. The buckling modes of cable-stiffened steel columns with three branch crossarm system could be symmetric, anti-symmetric, and asymmetric. [Display omitted] • A cable-stiffened column with three branch crossarm system was firstly experimentally studied. • A unique asymmetric buckling mode was experimentally demonstrated. • The effects of different parameters on the buckling behaviour of CSSCs were examined. [ABSTRACT FROM AUTHOR]

• The semi-skyrmions-based oscillation mode with GHz frequencies is observed. • The mode frequencies strongly depend on the in-plane dimension. • The mode frequency is affected by the material parameters. • The shape of the ellipse influences the velocity of the semiskyrmion. Magnetic skyrmions have been proved to be applicable to spin torque nano-oscillator. In this paper, we show dynamics of magnetic skyrmions in elliptical spin-valve nanopillar with perpendicular magnetic anisotropy (PMA) free layer and spin polarizer by using micromagnetic simulation. A novel semi-skyrmions-based oscillation mode with GHz frequencies appears in this geometry. We find that the mode frequencies strongly depend on the in-plane dimension of the elliptical nanopillar. The fitting function between the mode frequency and the perimeter of the ellipse is obtained. Simulation results also show that the exchange constant and the temperature effect have great influence on the mode frequency. [ABSTRACT FROM AUTHOR]