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Transition-metal-catalyzed carbonylation provides a useful approach to synthesize carbonyl-containing compounds and their derivatives. Controlling the regio-, chemo-, and stereoselectivity remains a significant challenge and is the key to the success of transformation. In the present study, we explored the mechanism and origins of the ligand-controlled regiodivergent carbonylation of alkynes with competitive nucleophilic amino and hydroxy groups by density functional theory (DFT) calculations. The proposed mechanism involves O(N)-cyclization, CO insertion, N–H(O–H) cleavage, C–N(C–O) reductive elimination and regeneration of the catalyst. The chemoselectivity is determined by cyclization. Instead of the originally proposed switch of competitive coordination sites, a new type of concerted deprotonation/cyclization model was proposed to rationalize the ligand-tuned chemoselectivity. The electron-deficient nitrogen-containing ligand promotes the flow of electrons during cyclization, and so it favors the O-cyclization/N-carbonylation pathway. However, sterically bulky and electron-rich phosphine controls the selectivity by a combination of electronic and steric effects. The improved mechanistic understanding will enable further design of selective transition-metal-catalyzed carbonylation. [ABSTRACT FROM AUTHOR]

The characteristics and functional properties of gelatin obtained from Chinese giant salamander (Andrias davidianus) skin were investigated. After alkaline and acetic acid pre-treatment, yield of the gelatin by hot water extraction (60°, 8 h) was 17.63 g/100 g (wet basis), and the gelatin contained 89.46 g/100 g protein, 0.3 g/100 g fat, and 0.41 g/100 g ash (dry basis). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results of the gelatin showed clear band pattern for collagen subunits,β- and α-chains. The gelatin contained 18.85% imino acids, 28.62% hydrophobic amino acids, and 19.68% essential amino acids, which is slightly lower than porcine skin gelatin (PSG). The gelatin exhibited thermo-reversible properties, with gel strength of 192.50 ± 11.47 g, rupture distance of 10.17 ± 0.20 mm, gelling temperature of 4.98°, and melting temperature of 18.04°, Emulsifying activity index (EAI) of the gelatin diminished with increasing concentrations from 10 to 40 mg/mL (p <.05), whereas the emulsifying stability index (ESI) improved significantly (p <.05). Higher concentrations (30 and 40 mg/mL) could significantly enhance the gelatin's foam expansion (FE) and foam stability (FS) (p <.05). Water absorption ability and oil absorption ability of the gelatin were 7.1 g water/g gelatin and 9.8 g oil/g gelatin, respectively. These results imply that the gelatin with good interfacial properties could potentially be used as a novel ingredient in food emulsion systems. Abbreviations: CGSS, Chinese giant salamander skin; CSG, Chinese giant salamander skin gelatin; PSG, porcine skin gelatin; EAI, emulsion activity index; ESI, emulsion stability index; FE, foam expansion; FS, foam stability; WAC, water absorption capacity; OAC, oil absorption capacity. [ABSTRACT FROM AUTHOR]

Vitamin E plays an important role in maintaining normal metabolism and physiological functions in animals. The health of fish fingerlings directly affects the rate of disease incidence in adult fish, and healthy fingerlings ultimately result in better breeding outcomes for cultured fish. To date, no previous studies have focused on the effects vitamin E deficiency on tilapia at the fingerling stage. In this study, we investigated the effects of dietary vitamin E on the growth, fat metabolism, antioxidant capacity, and inflammatory response of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) fingerlings. Vitamin E at different concentrations (0, 20, 40, 80, 160, and 320 mg/kg) was added to the diet and GIFT were fed for 55 days. Then, the GIFT were intraperitoneally injected with Streptococcus iniae and tested for infection. Vitamin E deficiency decreased growth and increased the food conversion ratio of GIFT fingerlings. Vitamin E deficiency also reduced the white blood cell count, increased hematocrit and hemoglobin contents in the blood, increased serum aspartate aminotransferase and alanine aminotransferase activities, and increased liver stress (P < 0.05). Vitamin E deficiency inhibited fat metabolism, down-regulated the expression of genes encoding lipoprotein lipase and heart-type and liver-type fatty acid-binding proteins, and increased serum total protein and fat deposition. Vitamin E deficiency significantly decreased superoxide dismutase, glutathione peroxidase, and catalase activities, increased malondialdehyde content, and caused oxidative damage. Vitamin E deficiency also up-regulated the expression of genes encoding interleukin 1β and tumor necrosis factor α in the head kidney, and stimulated a pro-inflammatory response. Overall, vitamin E deficiency inhibited growth, impaired fat metabolism, and disrupted the inflammatory response of GIFT fingerlings, whereas vitamin E supplementation in the diet reversed these negative effects. The diets with high concentrations of vitamin E (160–320 mg/kg) led to vitamin E accumulation in the fish tissues and rapid activation of the inflammatory response and antioxidant capacity in GIFT fingerlings exposed to S. iniae. • Vitamin E deficiency decreased growth and increased the FCR of GIFT. • Vitamin E deficiency increased hematocrit/hemoglobin in blood. • Vitamin E deficiency decreased antioxidant capacity of liver of GIFT fingerlings. • Vitamin E deficiency reduced LPL, H-FABP , and L-FABP and induced fat deposition. • Vitamin E regulated signaling response of pro-inflammatory gene expression. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the functional role of long non-coding RNA XIST in epithelial ovarian cancer (EOC). Methods: Detection of XIST expression levels in EOC tissues and cell lines was done using qRT-PCR. The relationship between XIST expression and clinicopathological features of EOC patients was compared and analyzed. The cumulative survival rates were calculated using Kaplan-Meier. A Cox hazard model was used to identify risk factors for survival. Lastly, the effects of XIST on EOC cell were assessed in vitro. Results: XIST was up-regulated in EOC tissues and cell lines. The expression of XIST was closely related to the tumor grade, distant metastasis, and FIGO stage in the EOC patients. The Cox regression analysis showed that high XIST expression was an independent predictor of prognosis in patients with EOC. In in vitro experiments, reducing XIST expression significantly suppressed cell proliferation, migration and invasion in EOC cells. Conclusion: XIST highly expressed in the EOC and plays a role in tumor promotion, which may be a potential target for the treatment of EOC. [ABSTRACT FROM AUTHOR]

Highlights • Water-assisted O 2 activation to form active OH∗ intermediates is in equilibrium. • The OH∗ species-assisted C H bond cleavage of glycerol is the possible RDS. • The oxidation of the primary and secondary hydroxyl groups have similar mechanism. Abstract Fundamental understanding of heterogeneously catalyzed aerobic, base-free oxidation of glycerol is highly desirable for sustainable and highly efficient chemical synthesis. In this work, Pt/CNTs catalyzed base-free oxidation of glycerol is investigated by combining experiments, DFT calculations and kinetics analysis. The solvent effects and kinetic isotope effects measurements as well as DFT calculations reveal that water-assisted O 2 activation to form active OH∗ intermediates is not in rate-determining step (RDS) but in equilibrium. Then, Langmuir-Hinshelwood kinetic models are developed and fitted with the experimental data. The OH∗-assisted C H bond cleavage of glycerol is discriminated as the RDS for the two parallel oxidation pathways of glycerol via primary or secondary hydroxyl groups, where the former case exhibits lower activation energy. The insights revealed here could guide the design and optimization of this catalytic process to generate the targeted products. [ABSTRACT FROM AUTHOR]

The paper presents a fundamental study of the properties and functions of well‐defined Ni−Ag surface alloys in methane decomposition and steam reforming, aiming at providing a better understanding of the principle for manipulating the catalytic activity of steam reforming and suppressing carbon formation. A better insight of structure‐property relationship was obtained by a kinetic study of the reactions on well‐defined surface Ni−Ag alloys, which were synthesized by surface redox reaction to selectively introduce Ag atoms into the surface of Ni particles supported on hydrotalcite derived support. The effects of Ni surface alloy with Ag are three‐folds in general. Replacement of Ni by Ag reduces the number of active site exponentially with increasing Ag site coverage. Ag site is not only inactive, but also significantly reduces the activity of adjacent Ni sites for methane activation in both methane decomposition and steam reforming. The third effect is to block the active sites for the nucleation and growth of the filamentous carbon. The rate of methane activation at Ni step sites was found to be 16–19 times of that on Ni terrace sites. The carbon formation rate decreased linearly with Ag site coverage and the effect of Ag is divided into two regions. At low Ag site coverages (0 to 0.055), Ag atoms preferentially deposit on Ni step sites, which has a significant effect on the methane activation compared to Ag atoms on the Ni terrace sites. The results reveal that the effects of Ag site on the carbon formation in the two regions are mostly caused by the different effects of Ag on the activity of Ni step sites and terrace sites, respectively, rather than the different ensemble sizes for carbon formation proposed in the literature. [ABSTRACT FROM AUTHOR]

We analyze the D→ππ decay channels at the leading order, αs corrections with the QCD factorization and the soft-gluon corrections with the light cone QCD sum rule. Comparing with the experimental result, the calculations of the D0→π+π- and D+→π+π0 decay are much better under the consideration of the contributions of factorization parts, αs corrections and soft-gluon effects. However, the calculation result is one order less than the experimental result in D0→π0π0 decay. It may have large effects of final state interaction in the decay channel. [ABSTRACT FROM AUTHOR]

To find the effect of conjugate and substituents on the intramolecular proton transfer, fourteen systems are studied using HF and CIS methods. The results indicate that the intramolecular proton transfer barrier decreases firstly, and changes a little for larger conjugate systems when the combined phenyl cycles are added from three to five. Hereby, we conjecture that the larger conjugate systems (more than three combined phenyl cycles) have little effect on the proton transfer barrier. Theoretical studies on substituents effect show that electronic donor groups enhance the H-bond and electronic acceptor groups reduce the H-bond. The position of substituents is another factor in the proton transfer reaction. The effect of all the substituents on the proton transfer barrier is small, so the character of mother molecule is crucial to the proton transfer reaction. Moreover, the linear analysis results show that the charges on the acceptor oxygen and the differences between the labile hydrogen and the acceptor oxygen have good linear relationship with the proton transfer barrier. [Copyright &y& Elsevier]

This paper presents fuzzy clustering algorithms for mixed features of symbolic and fuzzy data. El-Sonbaty and Ismail proposed fuzzy c-means (FCM) clustering for symbolic data and Hathaway et al. proposed FCM for fuzzy data. In this paper we give a modified dissimilarity measure for symbolic and fuzzy data and then give FCM clustering algorithms for these mixed data types. Numerical examples and comparisons are also given. Numerical examples illustrate that the modified dissimilarity gives better results. Finally, the proposed clustering algorithm is applied to real data with mixed feature variables of symbolic and fuzzy data. [Copyright &y& Elsevier]

Proton tautomerism of 1,5,8-trihydroxy-3-methoxyl-6-methyl-9,10-anthraquinone was studied using HF and configuration interaction all single-excitations methods with 6-31g(d, p) basis set for the ground and singlet excited states. The calculations indicate that the compound exhibits three strong intramolecular hydrogen bonds (IHB), and shows similar characters in their proton transfer processes considering the geometries and Mulliken charge population. It exhibits normal intramolecular proton transfer in the region III where only one pair of adjacent hydroxyl group and carbonyl group exists in a peri region. However, intramolecular proton transfer (IPT) is not favored in view of the energy trend along IPT coordinate in the region I and II, where two hydrogens of hydroxyl groups bond with a common oxygen of carbonyl group and exists two IHBs in the peri region. This energy trend is verified by the potential energy surface. Hereby, it can be conjectured that IPT is absence in the similar structure such as hypericin''s peri region and exists in hypomycin B from a theoretical point of view. Calculation results on the photophysical process show that the isomerization process is competitive with the intersystem crossing process, which facilitates the increase of triplet state quantum efficiency and photosensitive activity. [Copyright &y& Elsevier]

The surface curvature of the carbon nanofibers (CNF) and the strong interaction between the metal and the graphene edges cause local deformation of metal nanoparticles, and thereby inducing a high degree of microstrain. Such lattice expansion has been shown to increase the activity of Ni crystals. This provides new opportunities to manipulate the catalytic activity of the metal. [Copyright &y& Elsevier]

Thermal tuning of the localized surface plasmon resonance (LSPR) of Ag nanoparticles on a thermochromic thin film of VO2 was studied experimentally. The tuning is strongly temperature dependent and thermally reversible. The LSPR wavelength λSPR shifts to the blue with increasing temperature from 30 to 80 °C, and shifts back to the red as temperature decreases. A smart tuning is achievable on condition that the temperature is controlled in a stepwise manner. The tunable wavelength range depends on the particle size or the mass thickness of the metal nanoparticle film. Further, the tunability was found to be enhanced significantly when a layer of TiO2 was introduced to overcoat the Ag nanoparticles, yielding a marked sensitivity factor ΔλSPR/Δn, of as large as 480 nm per refractive index unit (n) at the semiconductor phase of VO2. [ABSTRACT FROM AUTHOR]

We report on the utilization of localized surface plasmon resonance (LSPR) of Ag nanoparticles to tailor the optical properties of VO2 thin film. Interaction of nano-Ag with incident light yields a salient absorption band in the visible-near IR region and modifies the spectrum of VO2 locally. The wavelength of modification occurs in a limited spectral region rather than affects the full spectrum. The wavelength of modification shows a strong dependence on the metal nanoparticle size and shifts toward the red as the particle size or the mass thickness of nano-Ag increases. Also, we found that the wavelength can be shifted into the IR further by introducing a thin layer of TiO2 onto the nano-Ag. Interestingly, with the help of LSPR effects the VO2 film exhibits an anomalous thermochromic behavior in the modification wavelength region, which may be useful in optical switching applications. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is a critical element in soils, essential to plant growth. Long-term and intensively managed Lei bamboo (Phyllostachys violascens) stands are usually subjected to severe soil acidification and Mn activation. However, Mn migration from topsoil to deep soil induced by severe soil acidification was poorly recognized and studied. The distribution and changes of the total and the operationally defined Mn forms in soil profiles and its potential stress and environmental effect were investigated in a chronosequence of Lei bamboo stands (0, 2, 6, 11, and 16 years of stand age). The results showed that the Mn amount was significantly decreased in topsoil and accumulated in subsoil with the long-term and intensive fertilizer application. Soil exchangeable Mn and superphosphate extractable Mn demonstrated large different variation to total Mn, whereas their sum was largely higher than and highly correlated with 8-hydroxyquinoline (HQN) extractable Mn. Soil organic carbon, pH value, exchangeable bases, and soil redox simultaneously controlled soil Mn depletion. In conclusion, long-term and intensive fertilizer application leads to soil acidification and accelerated soil Mn depletion in bamboo stand soil, promoting Mn accumulation in bamboo shoots. [Display omitted] • Intensive fertilizer application caused bamboo stands acidification seriously. • Soil acidification accelerated Mn leaching and enriching in subsoil. • Severe acidification enlarged the risk of Mn enrichment in bamboo shoot. • Soil organic carbon, pH, and exchangeable bases and soil redox controlled soil Mn's leaching. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method to control the surface Mo:C ratio by carbonization flow is discovered for the first time. • The relationship between the surface Mo:C ratio and the reactivity is established. • The low temperature water gas shift reaction activity depends on the electron transfer capability of the surface. • The catalysts with low Mo:C ratio improve catalyst stability. The low-temperature water–gas shift (WGS) reaction is an important industrial process for producing hydrogen and reducing carbon dioxide emissions. The α-MoC 1-x catalysts have shown promising performance in WGS reactions, but their activities are highly dependent on the surface structure. In this study, we investigated the effect of surface Mo and C ordinations on the low-temperature WGS activity of Pt/α-MoC 1-x catalysts using both experimental and theoretical methods. Our results reflected that as Mo: C ratio decreases, the surface free carbon and reduced number of Mo active sites led to a weakened electron transfer ability, resulting in poor catalytic activity. The 0.4% Pt/α-MoC 1-x -50 catalyst displayed superior hydrogen production activity and low apparent activation energy (E app = 58.5 kJ/mol) at low temperatures (100–200 °C). Our density functional theory (DFT) calculations revealed that the high reactivity of the 0.4% Pt/α-MoC 1-x -50 catalyst was due to the strong electron transfer capability and increased number of surface Mo active sites. This study provides new insights into the structure–activity relationship and stability of α-MoC 1-x catalysts for the WGS reaction and lays the foundation for the design of WGS catalysts with high activity and stability at low temperature. [ABSTRACT FROM AUTHOR]

Although Cd accumulation varies among rice varieties is recognized, the underlying mechanisms are not well clarified. In this study, comparative transcriptome analysis were performed by hydroponic culture system with two rice varieties, Y1540 (high Cd accumulator) and Y15 (low Cd accumulator) under 20 μM Cd stress. Results revealed 17,320 differentially expressed genes (DEGs) in roots of Y15 (7,655 upregulated and 9,665 downregulated) and 17,386 DEGs in roots of Y1540 (8,823 upregulated and 8,563 downregulated) expose to 20 μM Cd stress. Gene ontology (GO) analysis enriched 24 and 26 terms in Y15 and Y1540 respectively, including 23 common terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed 27 and 28 significant pathways in Y15 and Y1540 respectively, with 19 common pathways. Different responses to Cd stress between cultivars were not only reflected in differently enriched GO terms and KEGG pathways but also in different DEGs of 23 common GO terms and significant sequences represented by p-values of 19 common KEGG pathways. Both cultivars resist Cd through common processes with different weights; hence glutathione metabolism, mineral absorption, biosynthesis of secondary metabolites, and degradation of aromatic compounds could be playing a more important role in Y1540, whereas ribosome biogenesis in eukaryotes, mismatch repair, aminoacyl-tRNA biosynthesis, and the cell cycle maybe playing a more important role in Y15. Weighted gene co-expression network analysis (WGCNA) showed that five and three modules were clustered in Y15 and Y1540, respectively, with yellow and brown modules in Y15 and brown modules in Y1540 being significantly related to Cd stress. Further analysis showed that most of hub genes in Y15 were related to signal transduction or transcription factors, while most of hub genes in Y1540 were related to binding, metabolic, and secondary metabolic processes, which demonstrated their different response patterns at transcriptomic level to Cd stress. [Display omitted] • Y1540 accumulated more Cd than that of Y15 in root. • Cd stress induced more up- and less down-regulated genes in Y1540 than Y15. • Both cultivars resist Cd through common pathways with different weights. • Y15 has transcription factor/signal transduction as core process in Cd resistance. • Y1540 use chelation/metabolic/compartmentalization as core process to resist Cd. [ABSTRACT FROM AUTHOR]

[Display omitted] • A transient kinetic model for half-reactions in the redox cycle. • A systematic study for 14 metal chlorides on the CuCl 2 /γ-Al 2 O 3 -based catalysts. • Tuning the redox behavior by affecting the reduction and oxidation steps. • Three types of promoters with different rate-determining steps. • Valuable insights into the reaction process and mechanism. This study investigates the promoter effects of 14 metal chlorides (NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , CeCl 3 , PrCl 3 , NdCl 3 , ErCl 3 , FeCl 3 , YCl 3 , and SnCl 3) on the CuCl 2 /γ-Al 2 O 3 -based catalysts used for ethylene oxychlorination. The study combines transient experiments of the two half-reactions in the redox cycle to understand the effects of different promoters on the reduction and oxidation rates of the catalysts. The results show that promoter doping can tune the redox behavior of the CuCl 2 /γ-Al 2 O 3 -based catalysts, affecting the reduction and oxidation steps, and the rate-determining step (RDS) changed between reduction and oxidation steps through the effects of different promoters. All the promoters have a positive effect on the reaction rate at steady-state, but the impact of promoter identity on steady-state CuCl 2 concentration is variable and related to the electronegativity of the promoter metal. This work provides a better understanding of the reaction process and mechanism and highlights the potential of promoter doping for improving the efficiency and stability of CuCl 2 / γ -Al 2 O 3 -based catalysts in ethylene oxychlorination. The approach of both transient and steady-state kinetic modeling and simulation is a reliable and efficient method to study promoter effects on reduction–oxidation reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both size and support effects of Au catalysts are explored for MAL conversion. • The Au edge site is identified as the main active site for MMA generation. • A kinetics strategy for disentangling Au geometric and electronic effects is presented. The direct oxidative esterification of methacrolein (MAL) has drawn considerable attention as a promising route to produce methyl methacrylate (MMA). Here, we report a kinetics strategy to identify the active sites of Au catalyst for its disentanglement of geometric and electronic effects on this reaction. A series of Al 2 O 3 and CeO 2 supported Au catalysts are prepared by urea deposition–precipitation method, whose particle sizes are tailored by changing the vacuum-drying temperature. Their catalytic activity is correlated with Au particle size based on a crystal structure modelling, in which the Au edge site is identified as the main active site. The reduction in the valence electron population of Au 5 d states facilitates the adsorption of MAL, thus the positive core-level shift of Au 4f levels for each support gives rise to a higher production of MMA. This kinetics strategy could be extended to the design of other metal catalysts for this reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] For the explosive and strongly exothermic direct propene epoxidation with H 2 and O 2 to synthesize propylene oxide, maintaining uniform gas flow and moderate reaction in the packed bed reactor is of prime industrial and scientific significance. Herein, randomly packed beds of spherical particles were simulated with resolved particle 3D computational fluid dynamics (CFD) under industrial conditions. Effect of particle size (i.e., 6, 8 and 10 mm) on performance of gas-phase propene epoxidation was numerically simulated. The fluid flow and temperature fields were fully coupled to the species and reaction distribution, including reactions in the particles and on catalyst surface. Based on the results of velocity, pressure drop, temperature and species distribution, heat transfer together with catalytic performance inside the fixed bed reactor, it is found that PPD-6 (Packed Particle Diameter 6 mm) model has a more uniform flow distribution, higher thermal conductivity and a lower temperature compared with PPD-8 and PPD-10. In addition, as packed particle diameter increases, the heat transfer capacity reduces and the temperature rise increases. As a result, the maximum hot spot temperature for the PPD-6 model is about 3 and 8 K lower than PPD-8 and PPD-10 model, respectively. In addition, the PPD-6 model has a more uniform reaction rate within the particles compared with the PPD-8 and PPD-10 models due to short diffusion path and high mass transfer capacity. Therefore, the PPD-6 model shows superior safety together with optimum conversion and selectivity. This work harbors tremendous referential significance to the design and scale-up of industrial reactors for propene epoxidation. [ABSTRACT FROM AUTHOR]

Graphical abstract The P-O-Fe bond and the redox cycle between N-P-O-Fe-O and N-P-O-Fe-O 2 on atomically dispersed Fe-N-P-C complex catalyst prepared directly form woody biomass efficiently reduced adsorption strength of OH*, which leads to outstanding ORR activity. Highlights • Atomically dispersed Fe-N-P-C catalysts produced from woody biomass. • Outstanding ORR performance achieved. • Fe charge in the active site identified as descriptor. • P-O-Fe bond and the redox cycle of active sites resulted in the high activity. Abstract Development of cost-effective electrocatalysts as an alternative to platinum for oxygen reduction reaction (ORR) is of great significance for boosting the applications of green energy devices such as fuel cells and metal-air batteries. Here we report a nitrogen and phosphorus tri-doped hierarchically porous carbon supported highly cost-effective, efficient and durable Fe single-site electrocatalyst derived from biomass. Combined aberration-corrected HAADF-STEM, XPS and XAFS measurements and theoretical calculations reveal the atomically dispersed Fe-N-P-C-O complex as the dominant active sites for ORR. This work also shows the design principle for enhancing the ORR activity of single Fe site catalysts with higher Fe charge, which can be manipulated by the coordinated structure in the active centre. Theoretical calculations reveal that the main effective sites are singleN-P-O-Fe-O centers, where the associated P-O-Fe bond can significantly lower the stability of strongly adsorbed O* and OH* on the catalytically active sites and thus give rise to enhanced ORR performance. The insights reported here open a new avenue for constructing highly efficient molecule-like heterogeneous catalysts in electrochemical energy technologies. [ABSTRACT FROM AUTHOR]

Introduction: For some cancers bone is the preferred site for metastasis and involves a cascade involving transition of epithelial cells to mesenchymal cells and subsequent intravasation to the blood and lymph vessels, and finally hematogenous dissemination to perivascular niches of the bone marrow sinusoids. It has been shown that protein kinase C can aid metastasis to bone. Hence, pharmacological inhibition of protein kinase C (PKC) activity is thought of as a potential therapeutic option in bone metastatic lesions. The objective of the current study was to investigate how PKCs exert their effect on bone cancer metastasis and to test the efficacy of pharmacological inhibition of PKC on bone metastasis.Material and Methods: The effect of the PKC inhibitor Go6983 on epithelial and mesenchymal cell marker expression in the osteosarcoma cell line DAN was determined by immunoblot and immunofluorescence analysis. The in vivo effect of Go6983 was evaluated with a xenograft model using DAN cells.Results: Treatment with transforming growth factor β (TGF-β) led to loss of the epithelial cell marker and gain of mesenchymal cell markers in the osteosarcoma cell line, DAN. This transition occurred concomitantly with PKC activation. TGF-β-mediated PKC activation resulted in activation of ribosomal protein 6 (S6), but not S6K1. Pharmacological inhibition of PKC activation attenuated these effects. In a xenograft model of experimental metastasis, pharmacological inhibition of PKC activation over a period of 4 weeks reduced both tumor burden and metastasis to lungs.Conclusions: Our results indicate that PKC potentiates tumor metastasis to the bone by potentiating translation increase and can be putatively inhibited by pharmacological inhibition. [ABSTRACT FROM AUTHOR]

Highlights • Acidic deep eutectic solvent was firstly used for rod-like chitin nanocrystal (ChiNC) preparation. • Chitin nanocrystal was successfully used as enzyme carriers for the pocine pancreas lipase immobilization. • The as-prepared immobilized enzyme exhibited high catalytic performance, stability. Abstract Chitin nanocrystal (ChiNC) was fabricated based on p-toluenesulfonic acid -choline chloride deep eutectic solvent treatment. The obtained ChiNC was about 12–44 nm in width and 206–399 nm in length. The crystalline structure and the functional groups of ChiNC were maintained during the preparation process. Moreover, porcine pancreas lipase (PPL) was successfully immobilized onto the ChiNC to form the immobilized PPL (PPL@ChiNC). The resulting PPL@ChiNC has enzyme loading and activity recovery of 35.6 mg/g and 82.5%, respectively. The thermal stability, pH and temperature adaptabilities of PPL@ChiNC was improved, comparing with free PPL. The demonstrated DES treatment process was efficient for ChiNC preparation and the as-prepared ChiNC exhibited great potentials in biocatalysis and biomedical field. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A large sampling (105 accessions vs. 2–16 accessions in earlier studies) has been achieved. • The species number of the genus is likely to double the most recent estimate following our study. • Leptochilu s is monophyletic and resolved as nested within the microsoroid ferns. • Major evolutionary lineages have been identified. • Leptochilus might have evolved at lower latitudes and progressively dispersed to and colonized higher latitudes. Abstract The newly defined fern genus Leptochilus contains about 50 species occurring in subtropical to tropical Asia and adjacent Pacific islands. The circumscription and phylogeny of the genus have been ambiguous and its species had been included in various genera such as Colysis , Dendroglossa , Kontumia , Microsorum , and Paraleptochilus. Previous molecular studies sampled only 2–4 molecular markers and 2–16 accessions of Leptochilus. In the present study, DNA sequences of six plastid markers of 105 accessions representing ca. 40 species of Leptochilus , including types of Colysis, Kontumia, Leptochilus, and Paraleptochilus , 39 species of six non- Leptochilus genera of Microsoroideae, and one species of Pyrrosia , are used to infer a phylogeny. Our major results include: (1) Leptochilu s is monophyletic and resolved as nested within the microsoroid ferns, but its relationships with other members of Microsoroideae are not well resolved; (2) Six well-supported major clades in Leptochilus are recognized, differing from one another in molecular, morphological, and geographical features; (3) Species related to L. macrophyllus representing earliest split in Leptochilus are identified; (4) The inclusion of Microsorum pteropus in Leptochilus is confirmed, whereas M. insigne is closely related to Leptochilus but not resolved as a member of the genus; (5) The species number of the genus is likely to double the most recent estimate following our study, and quite a few cryptic species should be recognized; and (6) A basal grade formed by three major clades is recovered and they are composed of species almost exclusively distributed at lower latitudes (the Malay Archipelago), whereas the shallow-level clades contain species distributed at mainly higher latitudes, suggesting that Leptochilus might have evolved at lower latitudes and progressively dispersed to and colonized higher latitudes. [ABSTRACT FROM AUTHOR]

Abstract Nitric oxide (NO) and nitrogen (N 2) (0.4/99.6, v/v) were flushed in a modified atmosphere packaging (NO-MAP) to preserve tilapia fillets at 4 °C. Compared with vacuum packaged (VAP) samples, NO-MAP samples had higher redness values, lower rigor extent and less drip loss. After storage of 15 days, nitrate levels in the fillets were lower than that of the nitrate/nitrite processed foods like ham and below the China National Standard of the maximum permitted limit. In addition, NO-MAP was more effective in improving tilapia quality than NO euthanasia of live tilapia and saturated NO solution immersion of tilapia fillets. The results suggested that NO-MAP could be a potential novel MAP technique in storage of tilapia fillets to improve the product quality, extend the shelf-life and reduce food safety risks. This technique also has the potential to be used for other fresh fish or meat packaging and storage. Highlights • Nitric oxide-modified atmosphere packaging (NO-MAP) was used in tilapia fillets. • NO-MAP improved fillets quality causing higher redness values and longer shelf-life. • NO-MAP caused less nitrate after the storage thus reduced the food safety risks. • NO-MAP was more effective in improving fillets quality than other NO-based methods. [ABSTRACT FROM AUTHOR]

Abstract The present study was conducted to investigate the effects of dietary glutamate (Glu) supplementation on flesh quality, antioxidant defense and gene expression related to lipid metabolism and myogenic regulation. A total of 600 Jian carp Cyprinus carpio var. Jian with the similar size (mean initial weight 126.40 ± 0.21 g) were randomly assigned to five dietary treatment groups for feeding 63 days: a basal diet, basal diet supplemented with 4, 8, 16, and 32 g kg−1 Glu. With Glu supplement, the relative shear force, hydroxyproline content, and pH value have been significantly increased, and cooking loss and lactate content have been significantly decreased in muscle. Muscle protein, lipid, and the total essential amino acid concentration were significantly improved by Glu. Meanwhile, dietary Glu supplementation also modified muscle fatty acid profiles. Additionally, Glu supplementation significantly enhanced GSH content and the activities and gene expression of CuZnSOD, GPx, GST, and GR in muscle. The enhanced antioxidant enzymes activities were modulated by Nrf2. The expression level of genes involved in myogenic regulation (MyoD, Myf5, myogenin, and Mrf4) and TOR were significantly elevated by dietary Glu supplementation. Moreover, dietary Glu supplementation increased FAS mRNA level and decreased LPL mRNA level. In conclusion, these results suggest that Glu is a potential role to improve muscle flesh quality and the underlying mechanism may be partly due to regulate lipid metabolism, myogenic regulatory factors, and antioxidative capacity induced by Glu. Highlights • Dietary glutamate supplementation improved flesh quality in Jian carp. • Dietary glutamate levels affect the expression of genes regulating specific transition points in myogenesis. • Dietary glutamate levels modified fatty acid profile by regulating gene expression related to lipid metabolism. [ABSTRACT FROM AUTHOR]

Elizabethkingia miricola is a Gram‐negative rod which has been incriminated in severe infections in humans. Recently, a serious infectious disease was identified in Chinese spiny frogs (Quasipaa spinosa), in the Sichuan Province of China; the disease was characterized by corneal opacity, the presence of ascites and neurological symptoms. A Gram‐negative bacillus was isolated from the liver, spleen and kidney of the diseased frogs. Experimental infection test revealed that the bacillus could infect the frogs Q. spinosa and the LD50 value was 1.19 × 106 cfu per frog. The isolated Gram‐negative bacillus was identified as E. miricola according to phenotypic characteristics, 16S rRNA and gyrB gene sequence analysis. The isolated strain was only susceptible to florfenicol among all investigated chemotherapeutic agents. Histological examination revealed that E. miricola infection caused pathological lesions to multiple organs and tissues, especially in the liver, brain, kidney. These results confirmed that E. miricola is an emerging pathogen of Chinese spiny frogs. [ABSTRACT FROM AUTHOR]

Highlights • H 2 adsorption energies are very similar on different facets and K preadsorbed on hcp Co. • H atom adsorption was site and facet dependent on hcp Co. • H 2 dissociation energy barriers were negligible (0–0.07 eV) on clean hcp Co. • K has a slight inhibiting effect on the H atom adsorption and H 2 dissociation. • Different K species (K and KOH) exhibit similar effect on H 2 dissociation on hcp Co. Abstract Trace amounts of potassium (K) have a significant influence on the activity and selectivity of cobalt-based catalysts in Fischer–Tropsch synthesis (FTS), in which hydrogen adsorption and dissociation is one of the initial and most important steps. In this work, hydrogen adsorption and dissociation behavior on typical facets ((0001), (10–11), (10–12), (10–15) and (11–20)) of hcp Co with and without adsorbed K were systematically studied. H 2 molecular adsorption results showed that H 2 mainly adsorbed in the perpendicular mode and close to the state of free H 2. Different facets and pre-adsorbed K did not show obvious effects on the H 2 adsorption energy. Atomic hydrogen adsorption was site and facet dependent, but the maximum hydrogen adsorption energy on the different facets of hcp Co were similar (-2.64 to -2.67 eV) with the exception on the (11–20) facet where the adsorption energy was significantly lower (-2.44 eV). K had a slight destabilizing effect on the H atom adsorption on the former Co surfaces due to a very weak repulsive interaction between K and H atoms. The initial H 2 dissociation had negligible energy barriers (0–0.07 eV) on the clean surface of hcp Co, suggesting the direct dissociative adsorption of H 2. The energy barriers for H 2 dissociation are mainly caused by the approach of molecular H 2 towards the Co surface and the rotation of the H 2 molecule from the perpendicular mode to the parallel mode. The H 2 dissociation energy barriers increase by 0.02–0.17 eV after the pre-adsorption of K, indicating a slight inhibition of H 2 dissociation by K. However, the energy barriers for H 2 dissociation in the presence of K were also small (0.05–0.21 eV). This indicates that H 2 dissociates readily at typical Co-based FTS reaction temperatures (210–240 °C), both in the absence and presence of K. Different K species (K and KOH) exhibit similar effects on H 2 dissociation on hcp Co. The B 5 sites on the stepped facets, the preferred sites for K adsorption are not the most favorable site for H 2 dissociation, and K slightly hinders H 2 dissociation at the B 5 site of hcp Co. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Highlights: • Sand was replaced by crumb rubber particles in concrete mixes at volume ratios of 10%, 30%, and 50%. • The damage modes and responses of rubber concrete slabs and normal concrete slabs were studied. • The scope of application for rubber concrete under blast loading was examined. Abstract We conducted explosion field tests on rubber concrete slabs with steel reinforcement, including four kinds of concretes with different mix proportions of volume fractions of rubber particles (0%, 10%, 30%, and 50%, termed NC, RC10, RC30, and RC50, respectively). In addition, we compared the measured overpressure at the center of a slab with some empirical models to verify the accuracy our model. Field testing results showed that the tensile zone damage of rubber concrete slabs is smaller than that of normal concrete slabs under large explosive charges. Additionally, we validated a numerical simulation employing Multi-Material ALE and Lagrangian algorithms using the data from field experiments and employed it to further study the deformation process during the field test. Finally, we showed that rubber concrete slabs with steel reinforcements are practical structures for blast resistance, especially when subjected to a large energy detonation. [ABSTRACT FROM AUTHOR]

Insect-resistance of transgenic Bacillus thuringiensis (Bt) cotton varies among plants organs and with different environmental conditions. The objective of this study was to examine the influence of soil salinity on Bt protein concentration in cotton squares and to elucidate the potential mechanism of Bt efficacy reduction. Two cotton cultivars (NuCOTN 33B and CCRI 07, salt-sensitive and salt-tolerant) were subjected to salinity stress under four natural saline levels in field conditions in 2015 and 2016 and seven regimes of soil salinity ranged from 0.5 to 18.8 dS m-1 in greenhouse conditions in 2017. Results of field studies revealed that Bt protein content was not significantly changed at 7.13 dS m-1 salinity, but exhibited a significant drop at the 10.41 and 14.16 dS m-1 salinity. The greenhouse experiments further showed similar trends that significant declines of the insecticidal protein contents in squares were detected when soil salinity exceeded 9.1 dS m-1. Meanwhile, high salinity resulted in significant reduction in contents of soluble protein and total nitrogen, activities of nitrate reductase (NR), glutamine synthetase (GS) and glutamic-pyruvic transaminase (GPT), but increased amino acid content, activities of protease and peptidase in cotton squares. High salinity also decreased root vigor (RV), root total absorption area (RTA) and root active absorption area (RAA). The extent of decrease of Bt protein content was more pronounced in NuCOTN 33B than CCRI 07, and CCRI07 exhibited stronger enzymes activities involved in square protein synthesis and higher levels of RV, RTA and RAA. Therefore, the results of our present study indicated that insecticidal protein expression in cotton squares were significantly affected by higher salinity (equal to or higher than 9.1 dS m-1), reduced protein synthesis and increased protein degradation in squares and reduced metabolic activities in roots might lead to the decrease of Bt protein content in squares. [ABSTRACT FROM AUTHOR]

Understanding the synergy between metal and zeolite for catalytic aquathermolysis harbours tremendous scientific and industrial importance. Herein, HZSM-5 is used as a model zeolite due to uniform physico-chemical structure, which is required to elucidate the intrinsic structure-performance relationship. We first devise a novel and scalable strategy to synthesize recyclable magnetic Fe 3 O 4 /HZSM-5 catalyst, which shows enhanced catalytic aquathermolysis performance compared to pure HZSM-5 catalyst. Moreover, the underlying synergy effect is then systematically elucidated by multi-techniques such as 1 H NMR, HRTEM, Py-IR, NH 3 -TPD, SARA and EL. Importantly, it is found that the change of acidity is not the dominating reason for enhanced performance. The synergy not only favors dispersion of Fe 3 O 4 nanoparticles on zeolite, but also effectively breaks C S bond and reduces the percentages of resin and asphaltene. Furthermore, the designed Fe 3 O 4 /zeolite catalyst effectively reduces the viscosity of heavy crude oil by 85.0%. This work sheds new light on the design of highly efficient heterogeneous catalysts for catalytic aquathermolysis. [ABSTRACT FROM AUTHOR]

Apela identified from zebrafish Danio rerio for the first time in 2013 is a novel endogenous peptide ligand for the apelin receptor. To study the role of apela in regulating fish feeding, the complementary (c) DNA sequence of apela of Siberian sturgeon Acipenser baerii was cloned for the first time. The apela cDNA fragment of 836 bp was obtained by cloning. The open reading frame (ORF) of apela was 165 bp encoding a 54 amino acid, including 22 amino acids signal peptide and two proteolytic sites. Phylogenetic tree analysis showed that A. baeriiapela was clustered with mammalian and amphibian sequences. A. baeriiapela messeger (m)RNA was widely distributed in 11 tissues related to feeding, with high expressions in brain, oesophagus and stomach, especially in the brain. The level of apela mRNA in brain increased significantly after feeding. On the first day of fasting, apela expression in brain was significantly lower than that of the fed group, but after fasting for 3–15 days, the expression of apela in A. baerii brain was significantly higher than that in the fed group. After refeeding apela mRNA expression was obviously reduced. These results suggest that apela plays a bidirectional role in feeding regulation of A. baerii, which may serve as a short‐term satiation factor and a long‐term hunger factor. [ABSTRACT FROM AUTHOR]

Catalytic hydrolysis of ammonia borane has tremendous potential as an energy-efficient approach to supply hydrogen for energy vehicles and portable electronic devices. Herein, DFT calculation is first performed on electronic properties of Ni 2 P and Ni 5 P 4 nanocatalysts. It is found that more electrons are transferred from Ni to P for Ni 5 P 4 , indicating that Ni 5 P 4 may show superior performance based on the electron effect. Therefore, Ni 2 P and Ni 5 P 4 with high purity are synthesized by the phase-controlled thermal decomposition approach. Gratifyingly, the Ni 5 P 4 catalyst exhibits the as-expected better catalytic activity than that of Ni 2 P catalyst. It also shows low activation energy and good stability. Furthermore, the structures and morphologies of both catalysts are characterized by multi-techniques such as XRD, HRTEM and XPS. The better performance could be ascribed to the higher positive charge of Ni together with the stronger ensemble effect of P. The insights sheds new light on the design of efficient Ni P catalysts for hydrogen generation. [ABSTRACT FROM AUTHOR]

Targeting protein for Xenopus kinesin‑like protein 2 (TPX2) activates Aurora kinase A during mitosis and targets its activity to the mitotic spindle, serving an important role in mitosis. It has been associated with different types of cancer and is considered to promote tumor growth. The aim of the present study was to explore the role of TPX2 in diagnosing prostate cancer (PCa). It was identified that TPX2 expression in PCa tissues was increased compared with benign prostate tissues. Microarray analysis demonstrated that TPX2 was positively associated with the Gleason score, tumor‑node‑metastasis (TNM) stage, clinicopathological stage, metastasis, overall survival and biochemical relapse‑free survival. In vitro studies revealed that the high expression of TPX2 in PCa cells improved proliferative, invasive and migratory abilities, and repressed apoptosis of the PCa cells, without affecting tolerance to docetaxel. The results suggested that TPX2 serves as a tumorigenesis‑promoting gene in PCa, and a potential therapeutic target for patients with PCa. [ABSTRACT FROM AUTHOR]

Glucose isomerase (GI) responsible for catalyzing the isomerization from d -glucose to d -fructose, was an important enzyme for producing high fructose corn syrup (HFCS). In a quest to prepare HFCS at elevated temperature and facilitate enzymatic recovery, an effective procedure for whole cell immobilization of refractory Thermus oshimai glucose isomerase (ToGI) onto Celite 545 using tris(hydroxymethyl)phosphine (THP) as crosslinker was established. The immobilized biocatalyst showed an activity of approximate 127.3 U/(g·immobilized product) via optimization in terms of cells loading, crosslinker concentration and crosslinking time. The pH optimum of the immobilized biocatalyst was displaced from pH 8.0 of native enzyme to neutral pH 7.0. Compared with conventional glutaraldehyde (GLU)-immobilized cells, it possessed the enhanced thermostability with 70.1% residual activity retaining after incubation at 90°C for 72 h. Moreover, the THP-immobilized biocatalyst exhibited superior operational stability, in which it retained 85.8% of initial activity after 15 batches of bioconversion at 85°C. This study paved a way for reducing catalysis cost for upscale preparation of HFCS with higher d -fructose concentration. [ABSTRACT FROM AUTHOR]

Baseline nucleoplasmic bridges (NPB) vary widely in the general population from different regions in the same country or from different countries. The baseline NPB level in the normal Chinese population and the factors affecting the baseline and radiation-induced NPB levels have not been explored yet. The cytokinesis-block micronucleus cytome assay was conducted on the peripheral blood samples of 121 healthy individuals for the baseline NPB and 52 healthy individuals for the 2 Gy γ-ray-induced NPB level. The effects of age and gender on the baseline NPB and 2 Gy γ-ray-induced NPB level were evaluated. The overall baseline NPB in the peripheral blood lymphocytes of 121 healthy adults from the general population in China was 0.46 ± 0.20 per 1000 binucleated (BN) cells. The overall baseline NPB in males (0.56 ± 0.15 per 1000 BN cells) was higher than that in females (0.36 ± 0.22 per 1000 BN cells, P < 0.05). The effect of age on the baseline NPB was not significant, except for females in the 40-year age group. The overall 2 Gy γ-ray-induced NPB frequency for male donors was lower than that for female donors (P < 0.01). No evident trend of the radiation-induced NPB level with increasing age was observed for both genders. For the baseline micronucleus (MN) and radiation-induced MN levels, the effects of gender and age were confirmed. Therefore, the gender of donors affects the baseline and radiation-induced levels of NPB and MN. In addition, the effect of the age of the donors on the baseline and radiation-induced NPB levels showed no clear pattern and needed to be further investigated. [ABSTRACT FROM AUTHOR]

• A series of Zn SACs synthesized via a ZIF-8-mediated sacrificial template strategy. • Zn–N–C–T exhibited high performance in transfer hydrogenation nitrobenzene to aniline. • The activity of Zn–N–C–T is closely related to the coordination number of Zn sites. • The hydrogenation mechanism over Zn–N–C–1223 is disclosed by the DFT calculations. Metal single-atom catalysts (SACs) have great potential to replace traditional nanoparticle catalysts in practical applications, however, the task-specific construction of SACs containing metal–nitrogen (M−N) moiety with tunable M−N coordination number remains a colossal challenging issue. Herein, we report a facile strategy to modulate the s-band of Zn by constructing N-coordinated Zn SACs (denoted as Zn–N–C–T, T stands for the pyrolysis temperature) with tunable nitrogen coordination number (denoted as Zn–N x , x = 2, 3, and 4) and Zn loadings (ranging from 0.8 to 6.8% by weight) via a metal–organic framework-mediated pyrolysis method. The catalytic activity of Zn–N–C–T is found to be closely related to the coordination number of Zn single atomic sites for the transfer hydrogenation of nitroarene to arylamine, using hydrazine hydrate as a hydrogen source under environmental benign conditions, among which the under-coordinated Zn–N 3 with defect and asymmetric electron distribution in Zn–N–C–1223 exhibits the best catalytic activity, followed by lower-coordinated Zn–N 2 with defect in Zn–N–C–1273 and saturated coordination Zn–N 4 in Zn–N–C–1123. Experimental results and theoretical analysis uncover that appropriately lowering the coordination number increases the electron density of Zn single atoms and simultaneously introduces H-acceptor sites, which cooperatively contribute to the enhancement of the performance for transfer hydrogenation. [ABSTRACT FROM AUTHOR]

Compared with the clarification method of adding Ca(OH) 2 and the traditional heating method, membrane filtration without adding Ca(OH) 2 and vacuum heating affect the aroma of brown sugar processing by reducing cations, pH and heating temperature. HS-SPME-GC-MS were used to extract and analyze volatiles formed in the production process of brown sugar (obtained by different clarification methods and heating methods), and aroma attributes were analyzed via quantitative descriptive analysis. The results showed that the green and fruity notes were higher in the brown sugar obtained by vacuum heating, especially for the samples without adding Ca(OH) 2 ; the roasted and caramel notes were enhanced by high-temperature. Meanwhile, the aroma attributes had the same tendency as the odorants. Sugarcane juice and syrup had similar volatiles compared to brown sugar. These data indicate that membrane filtration without adding Ca(OH) 2 and vacuum heating provided more fruity and green notes to brown sugar and enriched the brown sugar aroma. • GC–MS showed phenols significantly increased by vacuum heating. • Sensory profiling showed vacuum heating increased the green and fruity notes. • The samples were divided into three groups according to volatiles. • Sugarcane juice and syrup had similar volatiles. • There were more alcohols in sugarcane juice and syrups without adding Ca(OH) 2. [ABSTRACT FROM AUTHOR]

• The stainless steel wires were modified by chemical etching and immersion for SPME. • Supherhydrophobic wire exhibited excellent extraction capacity to six non-polar PAHs. • High extraction capacity was obtained for polar estrogens using the hydrophilic wire. • Hydrophobic/hydrophilic interaction was intimately related to the enrichment factor. Construction of different surface wettability is meaningful for the interaction between the sorbent surface and target components. In the current study, four kinds of stainless-steel wires (SSWs) with different hydrophobic/hydrophilic property were prepared and used as the absorbents to enrich the target compounds with different polarity. Comparative extraction of six non-polar polycyclic aromatic hydrocarbons (PAHs) and six polar estrogens was carried out by in-tube solid phase microextraction (IT-SPME). The results showed that two SSWs with the superhydrophobic surfaces exhibited high extraction capacity to the non-polar PAHs with the superior enrichment factor (EF) in the range of 29–672 and 57–744, respectively. In contrast, the superhydrophilic SSWs demonstrated higher enrichment efficiency for the polar estrogens than other hydrophobic SSWs. On the basis of optimized conditions, a validated analysis method was established using six PAHs as model analytes for IT-SPME-HPLC. Acceptable linear ranges (0.5–10 μg L−1) and low detection limits (0.0056–0.32 μg L−1) were achieved using the superhydrophobic wire modified by perfluorooctyl trichlorosilane (FOTS). The relative recoveries spiked at 2, 5 and 10 μg L−1 in the lake water samples were in the range of 81.5%–113.7%. The relative standard deviation (RSD) of intraday (≤0.8%, n = 3) and interday (≤5.3%, n = 3) tests demonstrated the good extraction repeatability for the same extraction tube. Satisfactory repeatability for the preparation of extraction tubes (n = 3) was also obtained with the RSD values in the range of 3.6%–8.0%. [ABSTRACT FROM AUTHOR]

[Display omitted] • SO 4 2− ion modification strategy on metal foils (Zn, Ag, Au and Cu) to boost the CO 2 electroreduction reaction. • Metal-SO 4 adlayer triggers bend activation of CO 2 via electron transfer from O (SO 4 2−) to the vacant orbital of C (CO 2). • The adsorption of H atom on metal sites is restrained by the metal-SO 4 adlayer. The most difficulty of efficient CO 2 electroreduction lies in the activation step that turns CO 2 into the CO 2 − radicals or other intermediates that can be further converted. To overcome this bottleneck, many efforts have been devoted to develop electrocatalysts to lower the overpotential of CO 2 activation, but they inevitably involve complicated or/and unscalable synthesis methods. Here we reported that the SO 4 2− ion modified metal foils, including Zn, Ag, Au and Cu, demonstrated ∼6.5, 1.4, 14 and 2.5 times of CO faradaic efficiency in K 2 SO 4 electrolyte compared to KHCO 3 electrolyte at −1.05 V vs. RHE. According to both experimental and DFT studies, the electron-rich metal-SO 4 adlayer can activate CO 2 by bending the linear molecule of CO 2 through donating electrons to the antibonding orbital of CO 2 , thus facilitating the formation of key intermediate *CO 2 −. Moreover, the adsorption of H+ on metal sites is restrained by the metal-SO 4 adlayer, leading to a suppressed H 2 evolution activity. From a broader perspective, many catalysts can benefit from this approach to achieve more efficient CO 2 electrochemical reduction. [ABSTRACT FROM AUTHOR]

Abstract: An efficient method to synthesize tetrasubstituted furans using simple starting materials such as propargylic alcohols and 1,3-dicarbonyl compounds has been developed. It was discovered that InCl3 could catalyze this transformation efficiently while other simple iron, copper and silver salts were proven to be ineffective. [Copyright &y& Elsevier]

Taking the self-gravitation interaction and energy conservation, charge conservation and angular momentum conservation into account, we discuss the tunnelling characteristics of the charged particle from Sen black hole by the Hamilton-Jacobi method. The result shows that the tunnelling probability is related to the change of Bekenstein-Hawking entropy, and the actual radiation spectrum deviates from the pure thermal one, which is consistent with the result of Parikh and Wilczek and gives a new method to correct the Hawking pure thermal spectrum of Sen black hole. [ABSTRACT FROM AUTHOR]

• CH 4 direct dehydrogenation is preferred on Ni. • OH-assisted dehydrogenation of CH 4 is favored on Pt and Ni@Pt. • CO 2 direct dissociation is more favorable than H-assisted way on Ni. • H-assisted CO 2 dissociation is the dominant way on Pt and Ni@Pt. CO 2 reforming of methane (DRM) is a promising reaction for the carbon cycle in nature. Ni was found to be active in this process. However, single component Ni catalysts cannot meet the stability, activity and selectivity demands simultaneously. This paper presents a systematical density functional theory study to investigate the catalytic performance of Ni@Pt(1 1 1) core-shell surface compared with Ni(1 1 1) and Pt(1 1 1) in methane dry reforming. Two ways of O* and OH* assisted CH 4 dehydrogenation are considered in present work. CH 4 direct dissociation is more favored on Ni, while OH*-assisted CH 4 dehydrogenation is more competitive to proceed on Pt and Ni@Pt compared with direct way. Furthermore, Ni@Pt provides much less energy-demanding pathways for both CH and C oxidation, under the assistance of O* or OH*. Therefore, CH is much easier to be oxidized rather than decomposition into carbon on this surface, meanwhile, it is beneficial for carbon elimination and shows promising anti-carbon formation performance. Finally, free energy profiles are plotted at 1000 K and dominant reaction mechanisms of DRM conditions are proposed on three surfaces, respectively. On Ni(1 1 1), O* generated from CO 2 direct dissociation could provide dominant oxidant for CH* oxidation, while on Pt(1 1 1) and Ni@Pt, OH* originated from CO 2 H-assisted dissociation acted as the major oxidant for CH* oxidation. This work sheds some light on dominant reaction pathway and surface carbon formation, which could provide new mechanistic insight into CO 2 reforming methane on Ni-core/Pt-shell surface. [ABSTRACT FROM AUTHOR]

This work gives an insight into combined experimental and DFT study of water gas shift reaction on Ni catalysts at moderately elevated temperatures. The relative reactivity of surface adsorbed species O*, OH* and H* with CO* and their catalytic consequence in reaction mechanism and kinetics was studied. DFT investigation and microkinetic analysis pointed out that the favorable reaction pathway depends on the relative reactivity of O*, OH* and H* with CO* on the surface. It rationalizes the experimental observed changes in kinetics with hydrogen pressure. • Experimental and DFT study leads to WGS reaction mechanism insight on Ni catalyst. • It reveals dependency of the reaction mechanism and kinetics on hydrogen pressure. • Reaction pathway is dependent on relative reactivity of O*, OH* and H* with CO*. • DFT studies rationalize the experimental changes in kinetics with H 2 pressure. This paper presents a combined experimental and density functional theory study of the relative reactivity of surface species O*, OH*, and H* with CO* on nickel catalysts and their catalytic consequence in reaction mechanism and kinetics of water gas shift reaction. The kinetic study illustrates the hydrogen reaction order changes from 0.5 at relatively low hydrogen pressures to -1 at high hydrogen pressures. Detailed kinetic analysis indicated a hydrogen-induced change of the corresponding reaction pathway from hydrogen assisted CO activation to the redox mechanism with CO*+O* as a rate-determining step. The DFT investigation revealed that the surrounding surface H* atoms destabilize more significantly O* adsorption than H* adsorption, thus enhance more the reactivity of O* than H* towards reaction with CO* at high H* coverage. This kinetic study provides an insightful depiction for the future study of CO activation on other transition metals and the catalyst development for WGS reaction. [ABSTRACT FROM AUTHOR]

Myopia is one of the leading ocular disorders causing visual impairment worldwide, with the prevalence increasing rapidly. It's a significant global public health concern in 21st century. Myopia, particularly high myopia, often exhibits apparent familial aggregation, and multiple evidences have shown that genetic factors significantly contribute to its pathogenesis. Recent molecular technologies such as linkage analysis, candidate gene authentication, genome-wide association study (GWAS), and next-generation sequencing (NGS) have identified many myopia-associated loci and genetic mutations or variants. There exist ethnic variations in myopia occurrence as observed in populations of different genetic backgrounds, and different genetic components are found to be associated with the development of myopia-related phenotypes. A better understanding of the genetic basis triggering and controlling myopic changes may further help in myopia prevention. This review is to provide an updated overview of genetic findings in non-syndromic myopia. • Myopia is highly heritable and simultaneously affected by environmental factors. • 25 myopia loci have been revealed and ethnic variations are observed. • NGS-based studies, combined with familial co-segregation and functional analysis, have identified a number of myopia genes. • GWAS and a series of follow-up association studies have shown evidence of associations between numerous genes and myopia. • Further studies in this area may drive the discovery of new insights into the genetic aspects of myopia. [ABSTRACT FROM AUTHOR]

This letter treats the problem of `in transmission slots sharing a pool of n automatic repeat request slots. Two cases are treated. In one, these in slots belong to the same basestation-terminal pair, i.e., a frequency-division multiplexing channel. In the other, they are used by indifferent basestation-teflfliflal pairs, i.e., a time-division multiplexing channel. The smallest ii to satisfy loss and delay requirement is determined. [ABSTRACT FROM AUTHOR]

Abstract: A strategy is presented for making metal clusters encapsulated inside microporous solids selectively accessible to reactant molecules by manipulating molecular sieve size and affinity for adsorbed molecules. This expands the catalytic capabilities of these materials to reactions demanding high selectivity and stability. Selective hydrogen combustion was achieved over Pt clusters encapsulated in LTA zeolite (KA, NaA, CaA) in a propene‐rich mixture obtained from propane dehydrogenation, showing pore‐size dependent selectivity and coking rate. Propene tended to adsorb at channels or external surfaces of zeolite, interfering the diffusion of hydrogen and oxygen. Tailoring the surface of LTA zeolite with additional alkali or alkaline earth oxides contributed to narrowing zeolite pore size and their affinity for propene. The thus‐modified Pt@KA catalyst displayed excellent hydrogen combustion selectivity (98.5 %) with high activity and superior anti‐coking and anti‐sintering properties. [ABSTRACT FROM AUTHOR]

Abstract: A strategy is presented for making metal clusters encapsulated inside microporous solids selectively accessible to reactant molecules by manipulating molecular sieve size and affinity for adsorbed molecules. This expands the catalytic capabilities of these materials to reactions demanding high selectivity and stability. Selective hydrogen combustion was achieved over Pt clusters encapsulated in LTA zeolite (KA, NaA, CaA) in a propene‐rich mixture obtained from propane dehydrogenation, showing pore‐size dependent selectivity and coking rate. Propene tended to adsorb at channels or external surfaces of zeolite, interfering the diffusion of hydrogen and oxygen. Tailoring the surface of LTA zeolite with additional alkali or alkaline earth oxides contributed to narrowing zeolite pore size and their affinity for propene. The thus‐modified Pt@KA catalyst displayed excellent hydrogen combustion selectivity (98.5 %) with high activity and superior anti‐coking and anti‐sintering properties. [ABSTRACT FROM AUTHOR]

Hypobaric hypoxia (HH) at high altitudes leads to a wide range of cognitive impairments which can handicap human normal activities and performances. However, the underlying mechanism is still unclear. Adenosine A 2A receptors (A 2A Rs) of the brain are pivotal to synaptic plasticity and cognition. Besides, insult-induced up-regulation of A 2A R regulates neuroinflammation and therefore induces brain damages in various neuropathological processes. The present study was designed to determine whether A 2A R-mediate neuroinflammation involves in cognitive impairments under acute HH. A 2A R knock-out and wild-type male mice were exposed to a simulated altitude of 8000 m for 7 consecutive days in a hypobaric chamber and simultaneously received behavioral tests including Morris water maze test and open filed test. A 2A R expression, the activation of microglia and the production of TNF-α were evaluated in the hippocampus by immunohistochemistry and ELISA, respectively. Behavioral tests showed that acute HH exposure caused the dysfunction of spatial memory and mood, while genetic inactivation of A 2A R attenuated the impairment of spatial memory but not that of mood. Double-labeled immunofluorescence showed that A 2A Rs were mainly expressed on microglia and up-regulated in the hippocampus of acute HH model mice. Acute HH also induced the accumulation of microglia and increased production of TNF-α in the hippocampus, which could be markedly inhibited by A 2A R inactivation. These findings indicate that microglia-mediated neuroinflammation triggered by A 2A R activation involves in acute HH-induced spatial memory impairment and that A 2A R could be a new target for the pharmacotherapy of cognitive dysfunction at high altitudes. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae (group B streptococcus GBS) is a Gram-positive pathogen capable of infecting a variety of fish, including tilapia, which results in huge economic losses for aquaculture. Elongation Factor Tu (EF-Tu) is a highly conserved moonlighting protein in GBS. Recent studies have implicated EF-Tu as one of the most important virulence factors of microbial pathogens with high immunoreactivity, which makes it a target for vaccine development. In the present study, the EF-Tu-encoding gene of GBS, HN0303 , isolated from tilapia, was cloned and expressed in Escherichia coli . Surface specific stain showed that GBS can be recognized by rabbit anti-recombinant EF-Tu (rEF-Tu) antibodies. Rabbit anti-rEF-Tu serum blocking assays showed that EF-Tu participated in GBS adhesion to Epithelioma popuasum cuprini cells. Active immunization with Freund's incomplete adjuvant plus recombinant EF-Tu induced antigen-specific antibodies in tilapia, and generated moderate immune protection (relative percentage of survival was 70%). In an enzyme linked immunosorbent assay, tilapia antisera showed an antibody titer of 1:500. These observations suggested that GBS EF-Tu was present on the membrane, and that was capable of inducing immunity and protecting tilapia against infection. EF-Tu thus constitutes a candidate molecule for vaccines against GBS. [ABSTRACT FROM AUTHOR]