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Self-lubricated WC-Ni-Cr-based composites with WS 2 were fabricated by pulsed electric current sintering at different temperatures and pressures. The density and hardness of the composites were investigated, and the densification effects of sintering temperature and pressure were discussed. The applied pressure over 250 MPa along with a sintering temperature as low as 950 °C could densify the sintered composite while protecting the disulfide from decomposition. The tribological properties of the composites were also tested under sliding wear conditions in air. The composite with WS 2 sintered under high pressure could provide a lower friction coefficient than WC-Ni-Cr cermet without the addition of WS 2 . The test results are discussed together with the morphology of the polished surfaces and wear tracks. The presence of WS 2 and sulfur element in the composites was analyzed with the help of scanning electron microscopy, Raman spectroscopy and energy-dispersive X-ray spectroscopy. WS 2 in the composite appears to be transferred to the contact area with other wear debris during sliding and reduces the friction coefficient. [ABSTRACT FROM AUTHOR]

• Pulsed electric field (PEF) improves the reaction efficiency of dialdehyde starch. • The PEF-assisted DAS exhibited shrinkage and pits, and had a larger particle size. • The solubility of the DAS (12 kV/cm PEF- assisted oxidation) improved by 70.2%. • Increment in the strength of the PEF, led to a decrease in the viscosity of the DAS. The structural and physicochemical properties changes of corn starch oxidized by sodium periodate under the assistance of pulsed electric fields (PEF) were studied. It was found that dialdehyde starch (DAS) particles produced by PEF-assisted oxidation exhibited shrinkage and pits, and had a larger particle size when compared to the control without PEF. The solubility of the DAS (12 kV/cm PEF- assisted oxidation) improved by 70.2% when compared to the native starch. Increment in the strength of the PEF, led to a decrease in the viscosity of the DAS. In addition, the aldehyde group content of the DAS produced by PEF-assisted oxidation exhibited shrinkage and pits, and had a larger particle size when compared to the control increased by 11.6% when compared with the traditional oxidation method. PEF is an effective method to promote oxidation reaction of starch. [ABSTRACT FROM AUTHOR]

Abstract: Mesenchymal stem cells (MSCs) can self-renew and differentiate into osteogenic, chondrogenic, adipogenic and myogenic lineages. It's reported that bone morphogenetic protein 9 (BMP9) is one of the most potent osteogenic BMPs to initiate the commitment of MSCs to osteoblast lineage. Cyclooxygenase-2 (COX-2) is critical for bone fracture healing and osteogenic differentiation in MSCs. However, the relationship between COX-2 and BMP9 in osteogenesis remains unknown. Herein, we investigate the role of COX-2 in BMP9-induced osteogenesis in MSCs. We demonstrate that COX-2 is up-regulated as a target of BMP9 in MSCs. Both COX-2 inhibitor (NS-398) and COX-2 knockdown siRNAs can effectively decrease alkaline phosphatase (ALP) activities induced by BMP9 in MSCs. NS-398 also down-regulates BMP9-induced expression of osteopontin and osteocalcin, so does the matrix mineralization. The in vivo studies indicate that knockdown of COX-2 attenuates BMP9-induced ectopic bone formation. In perinatal limb culture assay, NS-398 is shown to reduce the hypertropic chondrocyte zone and ossification induced by BMP9. Mechanistically, knockdown of COX-2 significantly inhibits the BMP9 up-regulated expression of Runx2 and Dlx-5 in MSCs, which can be rescued by exogenous expression of COX-2. Furthermore, knockdown of COX-2 apparently reduces BMP9 induced BMPR-Smad reporter activity, the phosphorylation of Smad1/5/8, and the expression of Smad6 and Smad7 in MSCs. NS-398 blocks the expression of BMP9 mediated by BMP9 recombinant adenovirus. Taken together, our findings suggest that COX-2 plays an important role in BMP9 induced osteogenic differentiation in MSCs; BMP9 and COX-2 may form an important regulatory loop to orchestrate the osteogenic differentiation in MSCs. [Copyright &y& Elsevier]

Abstract: For the 10 MW High Temperature Gas Cooled Reactor (HTR-10), the residual heat of the spent fuel could be removed by natural ventilation in loading process. The spent fuel storage tank could shield radiation; the outside is covered by an iron sleeve, the spent fuel tank would be stored in atmosphere after fully loaded, and the residual heat could be discharged by natural ventilation in interim storage stage. The calculation showed that, the maximum temperature locates in the middle of the fuel pebble bed in the spent fuel tank in loading process and interim storage stage, and the temperature decrease gradually with radial distance, the temperature in the tank body and sleeve is evenly, it is feasible to remove the residual heat of the spent fuel tank by natural ventilation, and in the natural ventilation condition, the temperature of the spent fuel and the tank is lower than the temperature limit, which provides theoretical evidence for the choice of the residual heat removal method in loading process and interim storage stage. [Copyright &y& Elsevier]

Abstract: The gas separator is the key apparatus of the fuel handling and storage system in High Temperature Gas Cooled Reactor(HTGR), the flow field and pressure field in the gas separator with different design schemes were studied with computational fluid dynamics program FLUENT, which could provide theoretical evidence for design optimization of the gas separator. The result showed that impinging jet was detected in the initial design scheme, which caused vortex generation, besides, the interaction between impinging jet led to vortex between small holes. The size and number of the small holes in the horizontal pipe wall had significant effect on reducing the flow resistance. The pressure drop of the gas separator could decrease significantly by increasing the holes number under the vertical pipe as much as possible, which could reduce the mix between the jet and the surface. The pressure drop in the final design fell to about half of the value compared with the initial design scheme, which could reduce the energy consumption, and improve the system operation's stability. [Copyright &y& Elsevier]

Artemisia ordosica Krasch. (AOK) has been used for rheumatic arthritis, cold headache, sore throat, etc. in traditional Chinese/Mongolian medicine and is used for nasosinusitis by local Mongolian "barefoot" doctors. Up to now, their mechanisms are still unclear. To evaluate the in vivo anti-inflammatory and allergic rhinitis (AR) alleviating effect as well as in vitro antimicrobial activities of AOK extracts to verify its ethno-medicinal claims. Crude extracts (methanol/95%-ethanol/ethyl acetate) of AOK root/stem/leaf and fractions (petroleum ether/ethyl acetate/n-butanol/aqueous) of AOK root extract were prepared. Xylene-induced ear swelling model in mouse and ovalbumin (OVA)-induced AR model in guinea pig were established. Ear swelling degrees of mice were measured. The numbers of rubbing movement and sneezes of guinea pigs were counted to evaluate the symptoms of AR. The serum levels of histamine, INF-γ, IL-2/4/10, and VCAM-1 were measured by ELISA assay. The histological changes of nasal mucosa were investigated by light microscope after H&E staining. Antimicrobial activities of AOK extracts were also tested. LC-MS/MS analysis was performed to characterize the constituents of active extract and molecular docking was conducted to predict the biological mechanism. In ear-swelling model, extract (100.00 mg/kg) from the ethyl acetate layer of 95% ethanol (100.00 mg/kg) showed better swelling inhibition in mice than positive control (dexamethasone, 191.91 mg/kg). In AR model, extract from the ethyl acetate layer of 95% ethanol significantly alleviated the AR symptoms in guinea pigs, decreased the serum levels of histamine, INF-γ, IL-2/4/10, and VCAM-1, and reduced the infiltration of eosinophil in nasal mucosa. For Staphylococcus aureus , the ethyl acetate extract of AOK stem showed the highest inhibition (MIC=1.25 mg/mL), for Escherichia coli , n-butanol layer of 95% ethanol extract of AOK root showed the highest inhibition (MIC=15.00 mg/mL), for Candida glabrata , 95%-ethyl acetate extract of AOK leaf showed the best inhibition (MIC=0.064 mg/mL), while ethyl acetate and n-butanol layers showed similar inhibition on MRSA (MIC=7.50 mg/mL). LC-MS/MS characterization showed that dicaffeoylquinic acids account for more than 30% of ethyl acetate layer of AOK extract. Dicaffeoylquinic acids bind with histamine-1 receptor with high affinities and interesting modes. Extracts from AOK had interesting anti-inflammatory activity in mice, alleviating effect against OVA-induced AR in guinea pigs, and antimicrobial activities in vitro , which support the ethno-medicinal use of it. The main constituents in ethyl acetate layer of AOK root extract are dicaffeoylquinic acids and could bind with histamine-1 receptor well. These findings highlighted the importance of natural product chemistry study of AOK. Image 1 [ABSTRACT FROM AUTHOR]

Sanguinarine is a quaternary ammonium benzophenanthine alkaloid found in traditional herbs such as Chelidonium , Corydalis , Sanguinarum , and Borovula. It has been proven to possess broad-spectrum biological activities, such as antitumor, anti-inflammatory, antiosteoporosis, neuroprotective, and antipathogenic microorganism activities. In this paper, recent progress on the biological activity and mechanism of action of sanguinarine and its derivatives over the past ten years is reviewed. The results showed that the biological activities of hematarginine and its derivatives are related mainly to the JAK/STAT, PI3K/Akt/mTOR, NF-κB, TGF-β, MAPK and Wnt/β-catenin signaling pathways. The limitations of using sanguinarine in clinical application are also discussed, and the research prospects of this subject are outlined. In general, sanguinarine, a natural medicine, has many pharmacological effects, but its toxicity and safety in clinical application still need to be further studied. This review provides useful information for the development of sanguinarine-based bioactive agents. [Display omitted] • Multiple pharmacological activities of sanguinarine and its derivatives were concluded. • Mechanism of action of sanguinarine and its derivatives were detailly reviewed. • Outlooks about sanguinarine-related research were presented and discussed. [ABSTRACT FROM AUTHOR]

• PEF and enzymatic hydrolysis treatment improve starch's oil absorption. • PEF increases the pore volume and pore size values of the CPS. • PEF alters the crystalline nature, short-range ordering of CPS. • Cross-linking of CPS-PEF improves the thermal stability of CPS. In this study, corn porous starch (CPS) was firstly prepared using enzymatic hydrolysis, followed by pore formation enhancement using the treatment of a pulsed electric field (PEF). Subsequently, the PEF treated porous starch (CPS-PEF) was cross-linked with sodium trimetaphosphate (STMP) to investigate its structural and functional properties. The results showed PEF treatment increased the oil absorption of CPS by 26.92% and improved its specific surface area, total pore volume value, solubility and swelling power. After cross-linking of the CPS-PEF, C-O-P covalent bonds were formed between CPS-PEF molecules, resulting in a further increase in oil absorption and specific surface area properties. Moreover, the covalent bonds enhanced the intermolecular forces, resulting in increased thermal stability of the cross-linked porous starch (ScPS). The double modification resulted in significantly improved adsorption properties and better thermal stability of the ScPS, indicating that the double modification is an effective method for the preparation of porous starches. [ABSTRACT FROM AUTHOR]

Hypseodohenrin H (1), a cyclization product of nor-BPAPs with a 6/5/5 tricyclic ring system was characterized, along with it ring opening product, 1,7-seco-norhypseodohenrin (2). Their structures were elucidated by NMR, MS, and XRD analysis. Different from other cyclization product of nor-BPAPs that underwent a free radical process, the transformation from 1 to 2 was an ionic process. The bioactivity screening results showed that compounds 1 and 2 exhibited potent hepatoprotective activity with EC 50 value of 5.99 μM and 3.65 μM, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

A set of new metal coordination polymers constructed from a novel semi-rigid aromatic carboxylate ligand, namely, [M( L )( 4PBI )(H 2 O)] n (M = Ni, Co and Cu for 1 , 2 and 3 , respectively) and [Cd( L )( 4PBI )] n ( 4 ) ( H 2 L = 3-(1-carboxyethyl) benzoic acid; 4PBI = 2-(pyridin-4-yl)-(1 H )-benzoimidazole), have been synthesized by the hydrothermal reaction, which were characterized by element analyses, FT-IR, UV–Vis diffuse reflection spectra, X-ray single-crystal diffraction, powder X-ray diffraction, and thermogravimetric analyses (TGA). Complexes 1 , 2 and 3 are iso-structural. They form a one-dimensional (1D) linear chain structure connected by semi-rigid aromatic anion and further assemble into a three-dimensional (3D) supramolecular framework by π⋯π stacking and hydrogen bonding interactions. Complex 4 possesses two bi-nuclear units and displays two-dimensional (2D) layer which can further extend to a 3D supramolecular architecture via hydrogen bonding and weak packing interactions. Moreover, the luminescent property of complex 4 was investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

A lead compound 7 has antitumor effect, which was discovered by screening our small synthetic natural product-like compound (NPL) library. Based on the lead compound, a series of novel tricyclic diterpene analogs were synthesized and investigated for their activity against the growth of various tumor cell lines using the sulforhodamine B (SRB) assay. To our delight, most aromatic amide compounds exhibited more potent antitumor activity than the lead compound. The most active compound 19 ( QW30 ) showed an average IC 50 0.33 μM, which was 15-fold more potent than the lead compound. Most of the compounds with potent antitumor activity displayed less toxic on normal human fibroblasts (HAF) in comparison with the tumor cell lines. Especially 19 , its selectivity indexes (SI) between HAF and cancer cell lines was 17.3 times better than the positive control compound podophyllotoxin. The apoptosis, colony formation and transwell migration assays of 7 and 19 were performed on T47D cell line. The in-vivo antitumor effect of 19 was also observed in T47D tumor-bearing mice without obvious toxicity. [ABSTRACT FROM AUTHOR]

A series of D-ring fused 1,2,3-thiadiazole DHEA derivatives were synthesized and investigated for their activity against the growth of various tumor cell lines using the sulforhodamine B (SRB) assay. It is amazing that for these compounds, T47D cell line was much more sensitive than other tumor cell lines. The most potent saturated N-heterocyclic derivatives showed similar antitumor effect with the positive control compound ADM (adriamycin) on T47D cells, that was 44–60 folds more potent than the lead compound DHEA. Most compounds with potent antitumor activity displayed low toxicity on normal human fibroblasts (HAF). Especially compound 25 ( CH33 ) showed an IC 50 of 0.058 μM on T47D cells and its selectivity index (SI) between HAF and T47D was 364, which was 214 folds better than ADM (SI = 1.7). The apoptosis, colony formation and transwell migration assays of 25 were performed on T47D cell line. The primary mechanism study showed that 25 caused a dose-dependent induction of apoptosis, and induced phosphorylation of EphA2 and EphB3 in T47D cells. The in vivo antitumor effect of 25 was also observed in T47D tumor-bearing mice without obvious toxicity. [ABSTRACT FROM AUTHOR]

Anthocyanins and flavonols are important flavonoid metabolites in grapes, making a dominant contribution to the color, the mouth feel and even the flavor of grapes and wines. The accumulation of these flavonoids in grapes is greatly influenced by a many, diverse but interacting factors, of which variety and climate are among the most important ones. In the present study, the anthocyanin and flavonol profiles of four grape varieties ( Vitis vinifera L.), Cabernet Sauvignon, Carmenere, Syrah and Merlot, from five major wine regions in China were examined for two consecutive years (2006 and 2007). The results showed that the total anthocyanin content of the berry skins in these cultivars tended to increase from east to west in China, yet the proportion of the acylated anthocyanins displayed the opposite trend. It seemed possible that the western grape regions, with their high altitude and low annual rainfall, had an advantage in producing high level of anthocyanins. In addition, a high proportion of trihydroxylated flavonols were always found in the western region grapes, whereas dihydroxylated flavonols were more prominent in the lower altitude eastern regions. This suggested that the relative amounts of these flavonoid compounds may depend on their corresponding cultivar characteristics, while the amounts are more affected by the environmental factors where they were growing. [ABSTRACT FROM AUTHOR]

Highlights: [•] Adrenomedullin was released after acute intracerebral hemorrhage. [•] Adrenomedullin was an independent predictor for long-term outcome. [•] Adrenomedullin has high predictive value for long-term outcome. [Copyright &y& Elsevier]

[Display omitted] • A new microwave equipment that can emit CPM was constructed. • The phase transition of structure of starch by CPM treatments were investigated. • After CPM treated starch, the molecular structure was destroyed. • RWH was more destructive to the internal crystalline region than SWH. • The problems of uneven heating and poor experimental repeatability were improved. Although lots of work has reported the structural variations of starch in microwave treatment, most of them are detected in the environment with non-constant microwave power and inhomogeneous heating, and the results are always in poor repeatability. In this study, the equipment with constant microwave power (CPM) and homogeneous heating was designed. And the phase transition of multi-scale structure of rice starch (30% moisture content) caused by CPM treatments with two heating modes, namely rapid microwave heating (RWH) and slow microwave heating (SWH) were investigated systematically. SEM results showed that the surface of starch granules after CPM treatment were rough and broken, and the damage caused by RWH was more distinct than that by SWH. SAXS, XRD and 13C NMR results revealed that the CPM treatment decreased the degree of crystallinity and content of double helices of starch. Moreover, the influence of RWH on the variation of starch granules was greater than that of SWH, which can be attributed to the intensive friction and collision as well as the rapid evaporation of water in RWH treatment. Specifically, it exhibited greater destruction on the linkage of starch and the internal crystalline region in RWH treatment than SWH treatment, thereby resulting in more obvious damages on the lamellar and morphological structure of rice starch. In conclusion, CPM equipment has improved the problems of uneven heating and poor experimental repeatability. After CPM treated starch, the molecular structure of starch was destroyed, which provides a useful method to modify properties of starch. [ABSTRACT FROM AUTHOR]