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The article improves the process of dielectric barrier discharge (DBD) activated anode bonding. The treated surface was characterized by the hydrophilic surface test. The results showed that the hydrophilic angle was significantly reduced under nano-gap conditions and the optimal discharge voltage was 2 kV Then, the anodic bonding and dielectric barrier discharge activated bonding were performed in comparison experiments, and the bonding strength was characterized by tensile failure test. The results showed that the bonding strength was higher under the nano-gap dielectric barrier discharge. This process completed 110 °C ultra-low temperature anodic bonding and the bonding strength reached 2 MPa. Finally, the mechanism of promoting bonding after activation is also discussed.

Long noncoding RNA CRNDE (CRNDE) recently emerged as a carcinogenic promoter in various cancers including medulloblastoma. However, the functions and molecular mechanisms of CRNDE to the acquired drug resistance of medulloblastoma are still unclear. The transcript levels of CRNDE were examined in four medulloblastoma cell lines exposed to cisplatin treatment, and IC50 values were calculated. Effects of CRNDE knockdown or miR-29c-3p overexpression on cell viability, colony formation, apoptosis, migration, and invasion were assessed using the CCK-8, colony formation assay, flow cytometry, and Transwell assays, respectively. RNA pulldown and RNA-binding protein immunoprecipitation (RIP) were performed to confirm the molecular interactions between CRNDE and miR-29c-3p involved in medulloblastoma cells. The in vivo role of CRNDE knockdown or miR-29c-3p overexpression on tumor growth and apoptosis was evaluated in a xenograft mouse model of human medulloblastoma. The transcript levels of lncRNA CRNDE were significantly higher in cisplatin-treated tumor cells with higher IC50 values. Depletion of CRNDE inhibited tumor cell proliferation and colony formation, induced cell apoptosis, and suppressed migration and invasion in medulloblastoma cells. Moreover, overexpression of miR-29c-3p inhibited tumor cell proliferation and colony formation, migration, and invasion, and enhanced apoptosis and chemosensitivity to cisplatin. In addition, CRNDE was found to act as a miR-29c-3p sponge. Furthermore, in vivo experiments showed the CRNDE/miR-29c-3p interactions involved in medulloblastoma. Our study demonstrates that CRNDE acts as a critical mediator of proliferation, apoptosis, migration, invasion, and resistance to chemotherapeutics via binding to and negatively regulating miR-29c-3p in medulloblastoma cells. These results provide novel molecular targets for treatment of medulloblastoma.

To further enhance electrochemical performance of WS2-based materials in supercapacitors, a 3D architecture with WS2 nanoflakes interconnected and quantum dots anchored on N and S co-doped reduced graphene oxide (WS2/N,S-rGO) crumpled nanosheets is fabricated for the first time via a novel, facile and scalable approach, which is based on rapid solution combustion synthesis of the precursor and subsequent gas-solid phase sulfurization, and needs no such tedious processes as filtration, washing and drying. Significantly, the WS2/N,S-rGO hybrid possesses a specific capacitance of 1562.5 F g−1 at 1 A g−1 and a rate capability of 780 F g−1at 40 A g−1, which are superior to the currently-reported WS2-based electrode materials. As to the WS2/N,S-rGO hybrid, the 3D hierarchical architecture, synergistic effect between WS2 and N,S-rGO nanosheets as well as nitrogen and sulfur co-doping on rGO offer a variety of advantages such as larger contact surface area, shorter ion diffusion path, excellent charge transport and especially the enhanced pseudo-capacitance of rGO, and thus result in huge improvement in electrochemical activity, which demonstrate the WS2/N,S-rGO hybrid to be a superb anode material in supercapacitors.

In this study, the physiological values of volumes of plasma, cells, total blood and the F blood factors were identified in 24 adult tree shrews (Tupaia belangeri; 12 male and 12 female; average BW of 123.9±19.19 g). The two-compartment model method of Evans Blue dye was used to obtain the plasma volume and the venous hematocrit was measured by microhematocrit method. To establish the relationship between body weight (BW) and blood volume of tree shrews, We performed linear fitting for these two datasets. Results were analyzed according to gender and weight (120g). Statistical significance was assessed using the unpaired student t test and one-way ANOVA. The average volumes per 100g body weight of plasma, red blood cell (RBC) and total blood were 5.42±0.543, 3.24±0.445, and 8.66±0.680ml respectively. The mean body hematocrit, cardiac hematocrit, jugular vein hematocrit, femoral vein hematocrit, and tail vein hematocrit was 37.43±4.096, 39.72±3.219, 43.04±4.717, 40.84±3.041, and 38.71±3.442% respectively. The F cardiac was 0.94±0.072, F jugular vein 0.88±0.118, F femoral vein 0.92±0.111, and the F tail vein 0.97±0.117. Blood volume (ml) was 85.89103×BW (kg). This is the first study to provide the parameters of plasma volume, cell volume, total blood volume and F factor and a baseline for future research on blood physiology of tree shrews.

The surface composition and atomic arrangement of heterogeneous catalysts determine the surface chemistry and are necessary information for understanding surface catalytic reactions. Compared with monometallic catalysts, alloy catalysts are more complicated because of possible surface segregation or adsorption-induced segregation which may change under different reaction atmosphere. Construction of reasonable slab models to study reactions on alloy surfaces is of importance. Here we proposed a density functional theory based Monte Carlo method (DFT-MC) and used it to investigate the surface composition and atomic arrangement of the (111) surfaces of 1:1 PdAg, PdAu and PdCu alloys in vacuum and under the acetylene partial hydrogenation conditions modeled by co-adsorption of H and acetylene and of H and ethylene. Our DFT-MC simulations indicate that Au and Ag segregate on the PdAu(111) and PdAg(111) surfaces while Pd is enriched on the PdCu(111) surface under vacuum conditions. The surface Pd contents of PdAg and PdAu tend to increase under partial hydrogenation conditions. Analyses reveal that the co-adsorption energies on the ideal (bulk-cut) surfaces correlate linearly with the values on the segregated surfaces and there is also a linear relationship for the d-band centers between the ideal and segregated surfaces. The present study provides a way to construct more realistic models for studying reactions on alloy surfaces.

Short chain fatty acids (SCFAs) are the main products of indigestible carbohydrates that are fermented by microbiota in the hindgut. This study was designed to investigate the effects of oral SCFAs administration on the lipid metabolism of weaned pigs. A total of 21 barrows were randomly allocated into three groups, including control group (orally infused with 200 mL physiological saline per day), low dose SCFAs group (orally infused with 200 mL SCFAs containing acetic acid 20.04 mM, propionic acid 7.71 mM and butyric acid 4.89 mM per day), and high dose SCFAs group (orally infused with 200 mL SCFAs containing acetic acid 40.08 mM, propionic acid 15.42 mM and butyric acid 9.78 mM per day). The results showed that the average daily feed intake of SCFAs groups were lower than that of control group (P

Background & Aims Little is known about the composition and generation of plasma cell subsets in patients with hepatocellular carcinoma (HCC) and how these associate with outcomes. We investigated whether, or how, plasma cells differentiate and function in patients with HCC and mice with liver tumors. Methods We analyzed subset composition and distribution of plasma cells in HCC samples from 342 patients who underwent curative resection at the Cancer Center of Sun Yat-sen University in China; samples of non-tumor liver tissue were used as controls. We associated plasma cell profiles with patient outcomes. Tissue-derived leukocytes were analyzed by flow cytometry and real-time polymerase chain reaction. The ability of macrophages to regulate plasma cell differentiation was determined in ex vivo cultures of cells from human HCC tissues. C57BL/6 and BALB/c mice were given injections of Hepa1-6 cells, which formed hepatomas, or H22 cells, which formed ascitic hepatomas. Gene expression patterns were analyzed in human HCC, mouse hepatoma, and non-tumor tissues by real-time polymerase chain reaction. Mice with hepatomas were given injections of GSK126 (an inhibitor of histone H3 lysine 27 methyltransferase [EZH2]) and 5-AZA-dC (an inhibitor of DNA methyltransferases); tumor tissues were analyzed by immunofluorescence and immunohistochemistry for the presence of immune cells and cytokines. Results B cells isolated from HCCs had somatic hypermutations and class-switch recombinations to the IgG phenotype that were not observed in non-tumor tissues. Increased level of plasma cells correlated with poor outcomes of patients. Activated CD4+ T cells from HCCs stimulated C-X-C motif chemokine 10 (CXCL10) production by macrophages. CXCL10 bound CXC chemokine receptor 3 on B cells and signaled via extracellular signal–regulated kinase to cause them to become IgG-producing plasma cells. IgG activated Fc receptors on macrophages and induced them to produce interleukin 6, interleukin 10, and C-C motif chemokine ligand 20 (CCL20). In mice with hepatomas, depletion of B cells prevented generation of these macrophage, increased the anti-tumor T cell response, and reduced growth of hepatomas. However, these effects were lost after injection of CXC chemokine receptor 3–positive plasma cells. Human HCC and mouse hepatoma tissues had increased expression of DNA methyltransferase 1 and EZH2 compared with non-tumor tissues. Injection of mice with GSK126 and 5-AZA-dC induced expression of CXCL10 by tumor cells and caused plasma cell polarization, suppression of the anti-tumor T cell response, and hepatoma growth. Conclusions Human HCC tissues contain B cells with class-switch recombinations to the IgG phenotype. Activated CD4+ T cells from HCCs stimulate CXCL10 production by macrophages; CXCL10 binds CXC chemokine receptor 3 on B cells and causes them to become IgG-producing plasma cells. IgG activates Fc receptor in macrophages to produce cytokines that reduce the anti-tumor immune response. In mice with hepatomas, depletion of B cells prevented generation of these macrophages, increased the anti-tumor T cell response, and reduced growth of hepatomas. This pathway involves increased expression of DNA methyltransferase 1 and EZH2 by HCC and hepatoma cells.

Desorption rate curves of n-pentane on 5A zeolites at 418 K and 10-0.03 kPa were determined, and the effects of different macropore structure on desorption performance were analyzed. Results show that macropore distribution of 5A-1 concentrates in 0.25-1.25 μm, while that of 5A-2 ranges from mesopore category to 0.3 μm, but 5A-3 contains both pores of 0.01-0.1 μm and 0.2-2 μm inside, reflecting a broadest distribution; 5A-3, 5A-1 and 5A-2 reach desorption equilibrium after 1100 s, 1400 s and 2000 s respectively at 0.03 kPa, indicating that abundant macropores make n-pentane fastest desorbed from 5A-3, but this advantage gradually disappears with the increasing pressure; the effective desorption diffusion coefficients of n-pentane on 5A-1, 5A-2 and 5A-3 are 4.2×10-15-2.2×10-14 m2/s, 2.0×10-15-2.3×10-14 m2/s, 7.4×10-15-2.4×10-14 m2/s respectively, suggesting that plenty macropores make the diffusivity less affected by the changes of pressure, which can guarantee a fast diffusion rate of n-pentane even at low pressure.

Prediction of the behavior of systems containing halogenated silanes required modification of the mixing rules used for solution models. In this work, interaction parameters for the characterization of binary systems of methylvinyldichlorosilane, methyltrichlorosilane, methyldichlorosilane and toluene at 101.3 kpa were evaluated accounting for the ideality of the vapor phase. The experimental measurements of liquid phase composition and bubble point temperature were found to be well represented by the Wilson model. Computed values of the vapor phase mole fractions, activity coefficients and excess Gibbs free energies from the model were presented and discussed.

In this paper, a layered media was used as substrate in a infiltration treatment system for municipal wastewater treatment. The efficiency of this system on nitrogen removal was compared with that by traditional used gravel and the surface characteristics of the layered media were analyzed using SEM. The results show that the layered media used as substrate in infiltration treatment system for wastewater treatment is more efficient on nitrogen removal than gravel. In the system, artificial soil provides storage for contaminants and bio-ceramics support the living organisms. The alternative running of reactor with 12 hours’ feeding followed by 12 hours’ break may supply changing environments between oxidative and anoxic in the system which is important for nitrogen removal.

Highly selective molecularly imprinted layer-coated silica nanoparticles for paclitaxel were synthesized by molecular imprinting technique with a sol–gel process on the supporter of silica nanoparticles. The morphology of the obtained polymers was characterized by scanning electron microscopy (SEM). The binding properties of the imprinted polymers were evaluated through the equilibrium rebinding experiments. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymers with equilibrium dissociation constants of 0.0509 g•L-1and 0.0094 g•L-1, respectively. Paclitaxel and its analogue were employed for selectivity tests. The results indicated that the imprinted polymers exhibited good selectivity and specificity toward paclitaxel.

Pb2+-SiO2-TiO2(Hereinafter referred to as PST) composite catalysts were prepared by sol-gel method from tetrabutyl titanate(TBOT),tetraetethyl orthosilicate(TEOS) and lead nitrate. Properties of the catalyst were characterized by means of XRD and FT-IR. In addition, the photocatalytic activities of Pb2+ doped silicon-titanium composite samples were evaluated by the result of photocatalytic degradation of methyl orange as a model reaction under simulated sunlight.The results have been showed that the optimum Pb2+ doping concentration is 1.5% and the optimum heat treatment temperature is 500°C. Photocatalytic degradation conversion of methyl orange (10 mg/L) on PST catalyst could reach above 90.0% under simulated sunlight for 3h.

The synthesis of nanostructured Cu 2 O was conducted in a non-aqueous solution via polyol method at a temperature of 130 °C. It was found that the formation of Cu 2 O nanobelts was heavily dependent on the presence of surfactant cetyltrimethylammonium bromide (CTAB). Cu 2 O nanobelts with 100–400 nm in width and several micrometers in length were only observed when CTAB was used, whereas in other cases where CTAB was absent or CTAB was replaced with polyvinylpyrrolidone (PVP K-30), only spherical or cube-like particles were formed. The formation mechanism of Cu 2 O nanobelts was discussed.

SnO2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl4 and CO(NH2)2. It is found that different self-assembled patterns of SnO2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH2)2 to SnCl4 and the pretreatment of the substrate. Scattered SnO2 nanorods, for example, can be changed into flower-like patterns when the molar ratio of CO(NH2)2 to SnCl4 is raised, and well-aligned nanorod arrays can be formed when the pretreatment of the substrate is changed. In addition, some interesting patterns, e.g. tree-like patterns, can also be observed.

The temperature-programmed reduction process of two types of industrial ammonia-synthesis catalysts, A110 and ZA-5, which are, respectively, based on Fe{sub 3}O{sub 4} and Fe{sub 1-x}O precursors, were studied by in situ X-ray power diffraction (XRD). It has been found that the ZA-5 has lower reduction temperature and faster reduction rate, and its active phase alpha-Fe possesses a higher value of lattice microstrain than A110. The simulation based on Rietveld refinement has also shown that the shape of alpha-Fe grain of ZA-5 has a mixed shape of cube and sphere with more exposing (111) and (211) planes, while that of A110 looks like a concave cube with more exposing (110) planes. Based on the results obtained, a growth model of alpha-Fe during the reduction of Fe{sub 3}O{sub 4}- and Fe{sub 1-x}O-based ammonia-synthesis catalysts is proposed, and the origins for the activity difference has been also discussed. - Graphical Abstract: A proposed growth model of active phase alpha-Fe during reduction. Due to H{sub 2} diffusing easily into the pores, reduction starts on outside and inside surface simultaneously to form 'microcrystalline film', and the particles shrink during reduction which results in breaking of the aggregated oxide particle.

In this paper, a new kind of inorganic polymeric flocculant (IPF)—polysilicate ferro-aluminum sulfate (PSFA) was adopted to treat banknote printing wastewater. Effects of flocculants dosage on the colour and Chemical Oxygen Demand (COD) removal were examined. Experiments revealed that maximal colour removal efficiency of 98% and COD removal efficiency of 85% could be achieved at the optimal dosage of 30.33 g/L. And the colour and COD removal results treated by the PSFA flocculant were compared with those treated by aluminum sulfate. Experimental results showed that the most attracting parts of PSFA as compared with that of Al 2 (SO 4 ) 3 were: (i) lower COD and colour contained effluents; (ii) less quantity and volume sludge; (iii) better dewatering behaviour and solid–liquid separation flocs; (iv) providing a possibility to eliminate the high labour intensity plate-frame pressure procedure and replace it by ordinary filtration. Therefore, the using of PSFA generally offered a lower cost of operation and maintenance choice to treat banknote printing wastewater as compared to that of Al 2 (SO 4 ) 3 .

A simple chemical method was employed to coat carbon nanotubes (CNTs) with a layer of Co-B amorphous alloy. This technique involved a redox reaction using KBH4 as reducing agent and Na-2[Co(OH)(4)] complex as cobalt precursor. The amorphous character of the Co-B alloy was confirmed by high-resolution transmission electron microscopy (HRTEM) and Xray diffractogram analysis (XRD). These coated carbon nanotubes may be of great interest in magnetic research and as highly active catalysts in heterogeneous catalysis. (C) 2002 Published by Elsevier Science B.V.

Carbon nanotubes were formed in situ during the reduction of Fe 2 O 3 to Fe by a gas mixture of N 2 (200 sccm), H 2 (50 sccm), and cyclohexane (carried by H 2 ) at 750 °C. Transmission electron microscopy (TEM) investigation showed that most of the formed nanotubes were filled with metal nanoparticles or nanorods. Some nanotubes were even inserted with long continuous nanowires more than several hundred nanometer in length. High-resolution TEM (HRTEM) and electronic energy loss spectrum (EELS) of the filled nanotubes confirmed the presence of Fe inside the nanotubes. Based on the experimental results, a possible growth mechanism of the Fe-filled nantotubes was proposed.

Communication: Carbon-encapsulated cobalt nanoparticles are prepared over a range of temperatures and partial pressures by CVD from cyclohexane on prepared substrates consisting of ground powders Of SiO2 impregnated with Co(NO3)(2) and (NH4)(2)Mo2O7. The encapsulated cobalt nanoparticles are freed from the incorporated SiO2 and molybdenum by treating the deposition product with aqueous hydrofluoric acid. Extracted material is dispersed in ethanol and deposited on a carbon-coated and prior to investigation by high-resolution TEM.

Carbon nanotubes (CNT) were used as support medium to prepare Co catalysts for the selective dehydrogenation of cyclohexanol. Due to the unique structure and electronic property of CNT, Co/CNT possessed less acid sites than Co/activated carbon (AC). It seems to be easier to form multi-point complexes on Co/CNT than on Co/AC, resulting in a little higher selectivity to cyclohexanone and different distribution of by-products. The effect of K addition, attributed to electronic promotion, was also stronger on Co-K/CNT than on Co-K/AC.

Multi-walled carbon nanotubes, produced from catalytic decomposition of C2H2, were pre-oxidized by boiling nitric acid before being used as support media in a Co/carbon-nanotube monometallic catalyst system. The microstructures of nanotubes and the cobalt particles were examined by using high-resolution transmission electron microscopy and X-ray diffractometry. Various structural modifications on the nanotubes, such as thinned tubes, tubes with holes, and stepped surface with open edges of graphitic sheets were observed. In comparison with cobalt particles on unoxidized nanotubes, the cobalt nanoparticles deposited on the oxidized nanotubes have much smaller size and higher dispersion, resulting in significantly better catalytic performance (18.4% higher in initial conversion) in dehydrogenation of cyclohexanol to cyclohexanone.

In this experiment, synthetic porous calcium phosphate ceramics (hydroxyapatite–tricalcium phosphate) were prepared and implanted in dorsal muscles of dogs. The purpose was to study the biological processes prior to and during the morphogenesis of bone in extraskeletally implanted porous calcium phosphate ceramics. Specimens were harvested after implantation for 7, 15, 30, 45, 60, 90 and 120 days. Decalcified and undecalcified sections were prepared for alkaline phosphatase (ALP) histochemical localization and comparative histological analysis. The results show that bone morphogenesis in the pore regions of the extraskeletally implanted ceramics follows a complex process involving clot formation, vascular invasion, granulation-like tissue formation, polymorphic cell aggregation, osteoblast differentiation and bone formation. The characteristic feature preceding bone formation was polymorphic cell aggregation on the pore inner surface and near the invading capillaries or small venules. These cells were of various sizes and shapes, and some of them were positive for ALP activity. ALP-positive cell aggregates were more numerous where capillaries or venules were close to the pore inner surface. Osteoblast differentiation occurred within the cell clusters aggregated on the pore inner surface and bone matrix was secreted in direct contact with the ceramics. During bone formation, capillaries or small venules were always found close to the developing fronts of the osseous nidi. It is suggested that those cells which first appeared near the invading vasculature, the cells which aggregated on the pore inner surface and those cells which finally differentiated into osteoblasts may be interrelated in some way.

This study investigated downscatter effects in cardiac single-photon emission tomographic studies with simultaneous thallium-201/technetium-99m acquisition, and evaluated a previously proposed subtraction technique for downscatter compensation. Ten studies were carried out with different defect sizes and locations and varying activity distributions using four energy windows: 70+/-10% keV, 140+/-10% keV, 100+/-10% KeV, and 103+/-16% keV. The subtraction technique used the 100- or 103-keV data to remove scattered 99mTc counts from the 70-keV data. The size and contrast of infarcts in the dual-isotope 70-keV image were artificially decreased compared to those in the 140-keV image, caused by scattered 99mTc counts that were comparable to the primary 201Tl counts in the 70-keV window. The subtraction technique produced larger defects and more heterogeneous activity in the myocardial wall in dual-isotope 70-keV images compared to the corresponding 201Tl-only images. These artifacts were caused by the markedly different spatial distributions of scattered 99mTc counts in the 100-keV (or 103-keV) window as compared with the 70-keV window. It is concluded that scattered 99mTc photons may cause overestimation of ischemia and myocardial viability in simultaneous dual-isotope patient studies. The proposed subtraction technique was inaccurate and produced image artifacts. Adequate downscatter compensation methods must be developed before applying simultaneous 201Tl/99mTc acquisition in clinical practice.

Saponins are oligoglycosides with spirostane, steroid or triterpenoid aglycones as their genins, which constitute an important kind of natural product. Some of them exhibit prominent bioactivities, such as the saponins from Panax ginseng and Glycyrrhiza uralensis. Because of their high polarity and relatively complicated structures, it was time- and sample-consuming work to purify and identify them before the 1980’s. In the past decade, the continuing development of various advanced chromatographic materials and spectroscopic methods have made it possible to isolate and determine the structures of certain minor saponins ocurring only in small quantities in a short time.