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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]

• 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]

This paper focuses on the correlation between the oxidative reactivity and electrical properties of soot particles. Soot particles were produced from an n -heptane inverse diffusion flame and were sampled at different heights above the burner (HAB) using a thermophoretic and probe sampling techniques. The electrical properties were characterized by the electrical conductivity and work function, which were evaluated by an atomic force microscopy. The soot reactivity was assessed in terms of activation energy (E a) and characteristic oxidation temperatures, including peak temperature (T P) and burnout temperature (T b), using thermogravimetric analysis. As the soot particles gradually age, they have various electrical conductivity distributions. The average electrical conductivity presents an increase by three orders of magnitude when increasing the HAB from 10 to 60 mm. The work function of bulk soot particles shows an increase with the soot maturation. The soot reactivity gradually reduces during the soot maturation process because the values of E a , T P , and T b show increases with the increase in HAB. For the soot particles, the E a and T p have strongly positive correlations with the work function and with the logarithm of the electrical conductivity. Thus, electrical properties can serve as an indicator of soot reactivity. [Display omitted] • The electrical properties and reactivity of soot particles were assessed. • The electrical conductivity and work function increase as soot particles mature. • Soot reactivity decreases with the increase in logarithm of electrical conductivity. • Soot reactivity decreases with the increase in work function. • Soot electrical properties can serve as an indicator of soot reactivity. [ABSTRACT FROM AUTHOR]

• As of March 10, 2020, Italy had reported 9172 COVID-19 cases with 463 deaths. • We report the real-time reproductive numbers (R (t)) and case fatality rates for selected European countries (Italy, France, Germany, and Spain) by March 9, 2020. • The R (t) was greater than 2 in the selected European countries, indicating that the outbreak will continue. As a global pandemic is inevitable, real-time monitoring of transmission is vital for containing the spread of COVID-19. The main objective of this study was to report the real-time effective reproduction numbers (R (t)) and case fatality rates (CFR) in Europe. Data for this study were obtained mainly from the World Health Organization website, up to March 9, 2020. R (t) were estimated by exponential growth rate (EG) and time-dependent (TD) methods. 'R0' package in R was employed to estimate R (t) by fitting the existing epidemic curve. Both the naïve CFR (nCFR) and adjusted CFR (aCFR) were estimated. With the EG method, R (t) was 3.27 (95% confidence interval (CI) 3.17–3.38) for Italy, 6.32 (95% CI 5.72–6.99) for France, 6.07 (95% CI 5.51–6.69) for Germany, and 5.08 (95% CI 4.51–5.74) for Spain. With the TD method, the R value for March 9 was 3.10 (95% CI 2.21–4.11) for Italy, 6.56 (95% CI 2.04–12.26) for France, 4.43 (95% CI 1.83–7.92) for Germany, and 3.95 (95% CI 0–10.19) for Spain. This study provides important findings on the early outbreak of COVID-19 in Europe. Due to the recent rapid increase in new cases of COVID-19, real-time monitoring of the transmissibility and mortality in Spain and France is a priority. [ABSTRACT FROM AUTHOR]

Atomic force microscopy (AFM) was used to characterize the attractive force, adhesive force and adhesion energy between an AFM probe tip and nanometric soot particle generated by a premixed methane/oxygen flame. Different attractive force distributions were found when increasing the height above burner (HAB), with forces ranging from 1.1–3.5 nN. As the HAB was increased, the average attractive force initially increased, briefly decreased, and then underwent a gradual increase, with a maximum of 2.54 nN observed at HAB = 25 mm. The mean adhesive force was 6.5–7.5 times greater than the mean attractive force at the same HAB, and values were in the range of 13.5–24.5 nN. The adhesion energy was in the range of 2.0–5.6 × 10 −17 J. The variations observed in the average adhesion energy with increasing HAB were different from those of the average adhesion force, implying that the stretched length of soot particles is an important factor affecting the average adhesion energy. The Hamaker constants of the soot particles generated at different HABs were determined from AFM force-separation curves. The average Hamaker constant exhibited a clear correlation with the graphitization degree of soot particles as obtained from Raman spectroscopy. [ABSTRACT FROM AUTHOR]

This paper reports the effect of post-injection on pollutant emissions from a four-cylinder, direct-injection diesel engine fueled with biodiesel. Characteristics of exhaust pollutants were measured and evaluated for different main-post intervals (MPIs) and post-injection rates (PIRs). Measurements included emissions of carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NO x ) and particulate matter (PM), the particle number concentration distribution, and the reactivity and graphitization degree of the soot particles. Increasing the MPI or PIR increased the emissions of CO and THC but decreased those of NO x . At both low and high MPI values, higher PM emissions and particle number concentrations were observed for the 12 and 20% PIRs. At a PIR of 4%, PM emissions and particle number concentration increased with the increase in MPI. The size distributions of exhaust particulates exhibited a trimodal character under the applied operating conditions. The particle geometric mean diameter decreased with the increase in MPI, probably as a result of an increased yield of soluble organic compounds. Post-injection significantly impacted the reactivity of emitted soot particles, as evidenced by changes in the graphitization degree of soot. [ABSTRACT FROM AUTHOR]

This work studied the physicochemical characteristics of exhaust particles from a 1.48 L SIDI engine operating at different air–fuel ratios (AFRs). The morphology, fractal dimension, size and nanostructure were characterized using high-resolution transmission electron microscopy (HRTEM) in conjunction with electron energy-loss spectroscopy. The results indicate that SIDI aggregate particles produced at varying AFRs exhibit different morphologies. TEM images show that the aggregates obtained at an AFR of 14.7 are more compactly clustered than those generated under fuel-rich and fuel-lean conditions. The fractal dimension of SIDI aggregates at an AFR of 14.7 is found to be 2.21, a value that is larger than those from other AFRs. The primary particle sizes are distributed over a wide range of 5–55 nm at all AFRs, although the largest average primary particle diameter is found at an AFR of 14.7. Similar to diesel soot particles, SIDI soot particles also show characteristic shell-core and turbostratic structures at the nanoscale level. At an AFR of 14.7, the soot particles have a relatively short fringe length, a small fringe separation distance and high fringe tortuosity. As the AFR is increased, the sp 2 /sp 3 hybridization ratios first gradually decrease and then increase, with a minimum value of 0.156 at AFR = 14.7. SIDI soot particles are likely more reactive than diesel soot particles because they possess the relatively short fringe length, large separation distance and high tortuosity. [ABSTRACT FROM AUTHOR]

This work compared the surface functional group (SFG) types and concentrations and sp 3 /sp 2 hybridization ratios of in-cylinder soot samples generated by a heavy-duty diesel engine when employing n -heptane and a toluene/ n -heptane mixture (20% toluene by volume) as the fuels. In-cylinder soot samples were obtained from a total cylinder sampling system, and the SFGs and sp 3 /sp 2 hybridization ratios were analyzed using Fourier transform infrared and X-ray photoelectron spectroscopy. Despite the differences in fuel formulation, both n -heptane and n -heptane/toluene soot exhibited similar trends in terms of changes in the SFGs concentrations and sp 3 /sp 2 hybridization ratios during the combustion process. However, the addition of toluene to the n -heptane was found to increase the concentrations of all SFGs as well as the sp 3 /sp 2 hybridization ratio. The C OH and C O group concentrations exhibited a bimodal distribution for both the n -heptane and n -heptane/toluene soot throughout the combustion process, with the concentrations peaking in the premixed and diffusion combustion phases, respectively. In contrast, the relative amounts of aliphatic C H groups decreased in the premixed combustion phase, increased in the early diffusion combustion phase, and then decreased in the subsequent combustion phase. The sp 3 /sp 2 hybridization ratios obtained from both fuel soot were observed to initially decrease, then to increase before a decrease during the combustion process. There was a definite correlation between the sp 3 /sp 2 hybridization ratio and the relative concentration of aliphatic C H groups. [ABSTRACT FROM AUTHOR]

In this paper, the morphology, attractive force ( F at ), adhesive force ( F ad ) and Young's modulus ( E Y ) of diesel in-cylinder soot particles sampled by a total cylinder sampling system were studied using atom force microscopy. In each combustion phase, the equivalent diameter ( ED ), F at , F ad , adhesion energy and E Y present broad distributions. The pattern of ED distribution in the late combustion phase is similar to that in the late diffusion combustion phase, especially in the range of ED < 10 nm, suggesting that the particle size distribution changes little after the late diffusion combustion phase. Most isolated soot particles in each combustion phase possess a very low sphericity ratio. Three types of force curves are discovered for in-cylinder particles, and are introduced to identify the particle types. For the test carbonized soot particles, the SR appears to increase with an increase in ED in each combustion phase, and the AED shows a similar trend to that for all test particles during the combustion process. Due to the presence of plastic deformation for the nascent soot particles and the penetration for the liquid materials during the force measurement, the carbonized primary soot particles are employed for force analysis. As the combustion proceeds, the population-averaged values of F at and F ad show opposite trends; the attractive force, which is mainly driven by the Van der Waals force, gradually decreases. During the combustion process, the population-averaged adhesion energy decreases to a minimum in the late premixed combustion phase after which it then increases. The initial increase in the population-averaged Young's modulus ( AE Y ) is followed by a decrease before gradually increasing again from the early diffusion combustion phase. The AE Y shows a negative correlation with the fringe separation distance in the soot structure. [ABSTRACT FROM AUTHOR]

This work studied the evolution of in-cylinder polycyclic aromatic hydrocarbons (PAHs) in a diesel engine fueled with n -heptane, and explored the effects of adding toluene to n -heptane on in-cylinder PAHs. In-cylinder PAHs were sampled in a direct injection diesel engine using a total cylinder sampling system. PAHs were analyzed by gas chromatography–mass spectrometry with programmed temperature vaporization in the solvent vent mode. For n -heptane, the mass of total in-cylinder PAHs ( Σ M PAHs ) increased in premixed and late diffusion combustion phases, and decreased in early diffusion and late combustion phases. Among the 16 PAHs detected, Naphthalene (Nap) was the most abundant. PAHs with two benzene rings and one five-membered ring, such as Acenaphthylene, Acenaphthene and Fluorene, were also plentiful, implying that PAHs with five-membered ring could play an important role in the growth of in-cylinder PAHs. When adding 20 vol.% toluene to n -heptane, the evolution of ΣM PAHs was varied. The Σ M PAHs for n -heptane/toluene increased in premixed and early diffusion combustion phases, and decreased in late diffusion and late combustion phases. Toluene addition reduced the ΣM PAHs in the premixed combustion phase by up to 48% but increased ΣM PAHs by 30% in the early diffusion combustion phase. In the subsequent combustion phase, the ΣM PAHs was reduced by approximately 67%. For in-cylinder individual PAHs, toluene addition generally reduced the percentages of Nap in ΣM PAHs during the engine combustion process but increased the percentages of larger PAHs, indicating that toluene addition was conducive to the growth of PAHs to form larger PAHs. [ABSTRACT FROM AUTHOR]

• Oxygenated functional groups of soot particles increased with increasing OME 3 doping. • An increase in OME 3 blending enhanced soot aliphatic and aromatic C − H groups. • Blending OME 3 altered the spatial distribution of carbon-hybridised orbitals. • Incorporating OME 3 led to higher levels of O and H within the soot particles. Oxymethylene ether-3 (OME 3) is a promising synthetic e-fuel and alternative fuel for diesel engines. In contrast to diesel fuel, the use of OME 3 leads to a distinct combustion process in which soot particles are generated, which leads to changes in the chemical properties of these particles. These chemical properties are intricately connected to both the concentration and availability of potential radical sites, which, in turn, exert a substantial influence on soot oxidation during diesel particulate filter (DPF) regeneration. Hence, it is crucial to investigate the chemical features of soot samples. Nevertheless, a thorough investigation into the chemical features of n -heptane/OME 3 soot samples has not been fully understood. Here, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), elemental analyser, and thermogravimetric analysis (TGA) were used to examine the impact of blending OME 3 on chemical features of soot particles at various flame heights of an inverse n -heptane-OME 3 flame. XPS results from C1s and O1s peaks showed that OME 3 incorporation enhanced the concentrations of C = O, C–O, and O = C–O groups, especially C = O groups, with the percentage increase ranging from 11.93 % to 49.74 %. Similarly, the content of aliphatic C − H groups, along with O and H, increased with higher levels of OME 3 blending. Moreover, it was discovered that blending OME 3 altered the spatial distribution of hybridisation orbitals of carbon atoms, leading to a decrease in the sp2/sp3 ratio by as much as 40 % with the increase in the OME 3 blending ratio. The alteration in these chemical properties due to the addition of OME 3 enhanced the oxidative reactivity of soot particles, as manifested by up to a 15 % reduction in the measured activation energy. These findings are useful to optimise control strategies of DPF regeneration with the more widespread use of e-fuel. [ABSTRACT FROM AUTHOR]

Copper–cerium–zirconium catalysts loaded on TiO 2 prepared by a wet impregnation method were investigated for NH 3 -selective catalytic reduction of NO x , aiming to study the effects of the Ce/Zr molar ratio on the performance of Cu–Ce–Zr/TiO 2 catalysts. The Cu–Ce 0.25 –Zr 0.75 /TiO 2 sample exhibited nearly 100% NO x conversion over a wide temperature range (165–450 °C), which is strikingly superior to that of Cu/TiO 2 (210–389 °C) within the range of exhaust temperatures of diesel engines. The factors that govern the activity enhancement were extensively investigated by using a series of characterization techniques, namely X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and temperature-programmed reduction by hydrogen (H 2 -TPR). The results showed that the addition of zirconium and/or cerium refined the copper dispersion, prevented copper crystallization and partially incorporated the copper ions into the zirconia (ceira) lattice, which led to enhance the redox abilities of Cu–Ce–Zr/TiO 2 catalysts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reductions in CBC emissions were assessed for CFT diesel. [•] Significant reductions in emissions of total and individual CBCs were obtained. [•] The percentage reduction in the total CBCs decreased with an increase in engine load. [•] The percentage reduction in the total CBCs increased with increase in engine speed. [•] The ozone formation potential of CBCs emitted was strongly reduced with use of CFT. [ABSTRACT FROM AUTHOR]

The study made investigation on the combustion, performance and emissions of a modern dual fuel (DF) diesel engine using silicon dioxide (SiO 2) nanoparticle additives to methanol under different test conditions. The tests were conducted in three operating modes: diesel mode; methanol/diesel mode (methanol mode for short) and methanol-based SiO 2 nanofluid (MSN)/diesel mode (MSN mode for short) where the MSN was injected in the intake manifold. The results displayed that nano-SiO 2 inclusion in methanol increased the peak pressure by 8.6% in maximum and peak heat release rate by 4.3% in maximum. The brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) were improved with all the tested dosages of SiO 2 nanoparticles in the fuel, especially under high load conditions, the improvements of 5.1% in maximum and 6.2% in maximum for BTE and BSFC were achieved. Compared with the cases in methanol mode, CO, HC, NO x and smoke opacity in MSN mode were reduced by 38.5%, 55.4%, 5.2% and 55.6%, respectively. All the results indicate that the addition of SiO 2 nanoparticle in methanol could enhance the combustion and performance characteristics, and suppress the emissions of the DF diesel engines. • Nano-SiO 2 addition increases HRRmax and Pmax, especially at high engine load. • SiO 2 nanoparticles cause obvious ignition and combustion duration improvements. • Nano-SiO 2 additives in methanol increase BTE and lessen BSFC. • SiO 2 nanoparticles suppress significantly CO, HC, NO X and smoke emissions. [ABSTRACT FROM AUTHOR]

Inosine monophosphate (IMP) plays a significant role in meat taste, yet the molecular mechanisms controlling IMP deposition in muscle tissues still require elucidation. The present study systematically and comprehensively explores the molecular network governing IMP deposition in different regions of Jingyuan chicken muscle. Two muscle groups, the breast and leg, were examined as test materials. Using nontargeted metabolomic sequencing, we screened and identified 20 metabolites that regulate IMP-specific deposition. We maintained regular author and institution formatting, used clear, objective, and value-neutral language, and avoided biased or emotional language. We followed a consistent footnote style and formatting features and used precise word choice with technical terms where appropriate. Out of these, 5 were identified as significant contributors to the regulation of IMP deposition. We explained technical term abbreviations when first used and ensured a logical flow of information with causal connections between statements. The results indicate that PGM1, a key enzyme involved in synthesis, is higher in the breast muscle compared to the leg muscle, which may provide an explanation for the increased deposition of IMP in the breast muscle. We aimed for a clear structure with logical progression, avoided filler words, and ensured grammatical correctness. The activity of key enzymes (PKM2, AK1, AMPD1) involved in this process was higher in the breast muscle than in the leg muscle. In the case of IMP degradation metabolism, the activity of its participating enzyme (PurH) was lower in the breast muscle than in the leg muscle. These findings suggest that the increased deposition of IMP in Jingyuan chickens' breast muscle may result from elevated metabolism and reduced catabolism of key metabolites. In summary, a metaomic strategy was utilized to assess the molecular network regulation mechanism of IMP-specific deposition in various segments of Jingyuan chicken. These findings provide insight into genetic improvement and molecular breeding of meat quality traits for top-notch broilers. [ABSTRACT FROM AUTHOR]

• The analysis of the tensile deformation behavior of pristine and the PEEK irradiated by 1 MeV electrons was combined with SAXS. • In-situ synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) were used to analyze the changes in crystal and amorphous of PEEK which is during tensile deformation at room temperature. • The electron irradiation accelerates the disassemble of the original lamellae of irradiated PEEK and the schematic diagram is used to discuss the crystallization mechanism of the pristine and irradiated PEEK during tensile deformation. Polyether ether ketone (PEEK) is widely used as an electrical insulation material in aerospace field due to its excellent thermal and electrical properties. The changes in micro structure of the PEEK irradiated by 1 MeV electrons are studied by in-situ analysis of synchronous small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) during tensile deformation at room temperature. The tensile strength and the elongation at break of the irradiated PEEK decrease obviously, which is compared with the pristine one. The differential scanning calorimetry (DSC) analysis shows that the pristine PEEK begins to melt at 334.8 °C, the melting peak T m appears at 339.7 °C and a deeper exothermic crystallization peak T c appears at 297.8 °C during the cooling process. The crystallization peak temperature decreases with the increase of the irradiation fluences. The pristine PEEK has a significant scattering peak along the meridian direction of the SAXS pattern, which indicates that the crystal lamellae of the material exhibits a certain orientation, and the position of the scattering peak changes little after irradiation. The intensity of SAXS decreases with the increasing of stretching strains, and the descent rate increases with the increasing of the irradiation fluences. According to the WAXD analysis, the width at half height of the diffraction peak increases with the increasing of the stretching strain, and the peak tends to disappear during tensile deformation. The diffraction peak disappearance rate increases with the increasing of the irradiation fluences. [ABSTRACT FROM AUTHOR]

• Carboxyl group is the strongest site for adsorbing water. • The adsorption of water molecules weakens the C O bond and O H bond of carboxyl group. • The water molecules adsorbed at carboxyl groups are predicted as removed after 360 K. • The reorientation of water molecules in the process of replacement was analyzed. Water-desorption from lignite surface is an important issue in energy usage, however, corresponding researches are inadequate. Herein, in order to comprehensive understand the process of water-desorption from lignite surface, the interaction between water molecules and carboxyl group of lignite were investigated systematically from 298.15 K to 440 K, by using Car–Parrinello molecular dynamics (CPMD) method. The result indicated that in the key carboxyl group, the hydrogen site (H51) showed stronger adsorption capacity for water molecules than the oxygen site (O23) of the carboxyl group. Based on the statistical result, the water molecules adsorbed at H51 and O23 were considered as removed after 360 K. Vibration analysis was performed to acquire stretching frequencies of carboxyl group before and after water adsorption. The NBO analysis was used to study the reorientation of water molecules in a 0.14 ps trajectory when they replace with each other. The NBO orbitals obtained show that when water molecule is replacing, the two lone pair orbitals of O31 and O32 interact with the σ antibonding orbital of O24 H51 bond at the same time. It enhances the formation of new H-bond and facilitates the fracture of old H-bond. This work can not only reveal the mechanism of water desorption from lignite, but also lay valuable foundations for efficient utilization of lignite resource. [ABSTRACT FROM AUTHOR]

Research question: What are the protein levels and localization of oestrogen receptors (including ERa, ERb and G protein-coupled oestrogen receptor [GPER]) and hypoxia-inducible factor-1alpha (HIF-1a) in normal control endometrium (COEM) and ectopic endometrium from abdominal wall endometriosis (AWE). Design: AWE (n = 20) were obtained during surgery; COEM (n = 40) were collected by curettage. All tissues were obtained during the proliferative or secretory phase. Formalin-fixed paraffin-embedded tissues were used for immunohistochemical study for oestrogen receptors and HIF-1a proteins. Result(s): The expression of oestrogen receptors and HIF-1a in AWE differed from that in the corresponding menstrual cycle phase of COEM. Compared with COEM, ERa and HIF-1a were decreased whereas ERb and GPER were increased in AWE. The greatest difference was in GPER, with increased protein expression in both the cytoplasm and nucleus of endometrial epithelial and stromal cells, as well as a distinct change in localization from cytoplasmic expression to nuclear and cytoplasmic expression, compared with COEM. Conclusions: Our data suggest that the expression changes of oestrogen receptors and HIF-1a, especially GPER, are associated with AWE, which may provide new clues to understanding the cause of endometriosis. [ABSTRACT FROM AUTHOR]