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Compared with carbon nanotube (CNT) and graphene (GE) aerogels, the synthesis of three-dimensional (3D) carbon nanofiber (CNF) aerogels that are highly compressible, resilient under cyclic strains, and creep and fatigue resistant remains extremely challenging. Herein, a revolutionary green and scalable biosynthesis is presented, by which a novel 3D CNF aerogel derived from natural bacterial cellulose (BC) decorated with its mother bacteria is created. The as-prepared CNF aerogel possesses excellent mechanical resilience, ultra-low energy loss coefficient, and outstanding cycling stability, which are by far among the best performances for CNT and GE aerogels reported thus far. Furthermore, the CNF aerogel exhibits excellent creep and fatigue resistance and sensitive electrical conductivity change upon compression. Surprisingly, the as-prepared 3D CNF aerogel exhibits superhydrophilicity. These superb properties are attributed to the existing carbonized bacteria in the carbonized BC matrix that serve as crosslinks to strengthen the aerogel and buffers to store deformation energy. This study presents a breakthrough method for the construction of superb and cost-effective 3D CNF aerogel from natural biomass material.

To investigate the clinical feasibility of single-breath-hold (SBH) T2-weighted (T2WI) liver MRI with deep learning-based reconstruction in the evaluation of image quality and lesion delineation, compared with conventional multi-breath-hold (MBH) T2WI.One hundred and fifty-two adult patients with suspected liver disease were prospectively enrolled. Two independent readers reviewed images acquired with conventional MBH-T2WI and SBH-T2WI at 3.0 T MR scanner. For image quality analyses, motion artifacts scores and boundary sharpness scores were compared using nonparametric Wilcoxon matched pairs tests between MBH-T2WI and SBH-T2WI. With the reference standard, 89 patients with 376 index lesions were included for lesion analyses. The lesion detection rates were compared by chi-square test, the lesion conspicuity scores and lesion-liver contrast ratio (CR) were compared using nonparametric Wilcoxon matched pairs tests between the two sequences.For both readers, motion artifacts scores of SBH-T2WI were significantly lower than MBH-T2WI (P 0.001). Boundary sharpness scores of SBH-T2WI were significantly higher than MBH-T2WI (P 0.001). The lesion detection rates for SBH-T2WI were significantly higher than MBH-T2WI (P 0.001); the differences of lesion detection rates between the two sequences were statistically significant for small (≤ 10 mm) liver lesions (P 0.001), while not significant for larger (10 mm) lesions (P 0.05). Lesion conspicuity scores were significantly higher on SBH-T2WI than MBH-T2WI in the entire cohort as well as in both stratified subgroups of lesions ≤10 mm and 10 mm (P 0.001 for all). CRs for focal liver lesions were also significantly higher with SBH-T2WI (P 0.001).The SBH-T2WI sequence with deep-learning based reconstruction showed promising performance as it provided significantly better image quality, lesion detectability, lesion conspicuity and contrast within a single breath-hold, compared with the conventional MBH-T2WI.

Creatine (Cr) is an essential metabolite in the creatine kinase reaction, which plays a critical role in maintaining normal cardiac function. Chemical exchange saturation transfer (CEST) MRI offers a novel way to map myocardium Cr. This study aims to investigate the dynamic alteration in myocardium Cr during acute infarction using CEST MRI, which may facilitate understanding of the heart remodeling mechanism at the molecular level. Seven adult Bama pigs underwent cardiac cine, Cr CEST, and late gadolinium-enhanced (LGE) T

The objective of the present study was to investigate the effects of tannic acid (TA) on growth performance, blood parameters, antioxidant capacity, and intestinal health in broilers challenged with aflatoxin B1 (AFB1). A total of 480 broilers aged 1 d were randomly allotted into four treatments: 1) CON, control diet; 2) AF, CON + 60 μg/kg AFB1 of feed during days 1 to 21, CON + 120 μg/kg AFB1 of feed during days 22 to 42; 3) TA1, AF + 250 mg/kg TA; and 4) TA2, AF + 500 mg/kg TA. Average daily gain (ADG) and average daily feed intake (ADFI) were increased in the TA1 during days 1 to 21, days 22 to 42, and days 1 to 42 compared with CON and AF treatments (P0.05). Broilers fed the TA2 diet had greater ADG and ADFI than those fed the CON and AF diets during the finisher and the whole period (P0.05). Administration of TA decreased the relative weight of liver and kidney compared with broilers fed the AF diet on day 42 (P0.05). The blood activity of alanine transferase (ALT) and gamma-glutamyl transferase (GGT) was increased in the AF treatment compared with the CON (P0.05). Broilers fed the TA1 decreased the ALT content on day 21, and the level of ALT and GGT was decreased in the TA2 compared with the AF group on day 42 (P0.05). The activity of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) in plasma, and the hepatic glutathione S-transferase (GST) was decreased in the AF group compared with the CON group (P0.05). The TA decreased plasma malondialdehyde concentration, and increased plasma T-SOD, GSH-Px, total antioxidant capacity, and hepatic GST activity compared with the AF (P0.05). The crypt depth of the jejunum was decreased in the TA1 treatment on day 21, and the villus height of the ileum was increased in the TA2 group on day 42 compared with the AF treatment (P0.05). The cecal Lactobacillus counts on day 21 were tended to increase in the TA treatments compared with the AF (P = 0.061). In conclusion, dietary inclusion of 250 and 500 mg/kg TA could improve the growth, antioxidant capacity, and partially protected the intestinal health of broilers challenged with AFB1.Aflatoxin B1 (AFB1) is well known for its growth retardation, hepatotoxic, immunosuppressive, and other negative effects both in humans and poultry. Plant extracts such as tannic acid (TA) have been demonstrated as effective agents to control AFB1 contamination. The objective of this study was to evaluate the effects of Chinese gallnut TA in preventing aflatoxicosis in broilers. Broilers received one of four treatments: CON, control diet; AF, control diet with AFB1; TA1, AF + 250 mg/kg TA; TA2, AF + 500 mg/kg TA. Although AF did not decrease the growth performance of broilers, 250 and 500 mg/kg TA had greater average daily gain and average daily feed intake than those in the CON and AF. The relative weight of liver and kidney, blood alanine transferase, and gamma-glutamyl transferase activity were increased, and the antioxidant status was depressed in chicks fed the AF diet compared with the CON group. Dietary supplementation with 250 and 500 mg/kg TA ameliorated all the above-mentioned negative effects of AFB1. Moreover, the crypt depth of the jejunum was decreased, and the villus height of the ileum was increased in TA treatments compared with the AF. Conclusively, Chinese gallnut TA could be considered as a potential natural agent for the prevention of AFB1-induced oxidative and intestinal damage of broilers.

BACKGROUND Partial bile duct ligation (PBDL) model is a reliable cholestatic fibrosis experimental model that showed complex histopathological changes. Magnetic resonance imaging (MRI) features of PBDL have not been well characterized. PURPOSE To investigate the potential of MRI parameters in assessing fibrosis in PBDL and explore the relationships between MRI and pathological features. ANIMAL MODEL Established PBDL models. POPULATION Fifty-four mice were randomly divided into four timepoints PBDL groups and one sham group. FIELD STRENGTH/SEQUENCE 3.0 T; MRI sequences included T1-weighted fast spin-echo (FSE), T2-weighted single shot FSE, variable flip angle T1 mapping, multi-echo SE T2 mapping, multi-echo gradient-echo T2* mapping, and multi-b-value diffusion-weighted imaging. ASSESSMENT MRI examination was performed at the corresponding timepoints after surgery. Native T1, ΔT1 (T1native-T1post), T2, T2*, apparent diffusion coefficient (ADC) values, histogram parameters (skewness and kurtosis), intravoxel incoherent motion parameters (f, D, and D* ) within the entire ligated (PBDL), non-ligated liver (PBDL), and whole liver (sham) were obtained. Fibrosis and inflammation were assessed in Masson and H&E staining slices using the Metavir and activity scoring system. STATISTICAL TESTS One-way ANOVA, Spearman's rank correlation, and receiver operating characteristic curves were performed. P

Alcoholic abuse is one of the most serious causes of liver diseases worldwide. Although detailed molecular pathogenesis of alcohol-induced liver damages remains elusive with intensive debates, it has been widely recognized that hepatic damage caused by free radicals generated from alcohol metabolism is one of the most critical factors for alcohol-induced liver diseases. Betulinic acid is a potent antioxidant with additional known pharmacological safety characteristics and minimal toxicity. However, poor solubility limited its usage. In this study, we assessed the efficacy of BAN, a betulinic acid and nucleoside hybrid with good water solubility, in reversing acute liver damages using an established alcohol overdose animal model. The results indicated that BAN is an extremely promising therapeutic agent against acute alcohol-induced liver damage. BAN effectively protects liver from alcohol damage by reducing serum ALT level by up to 47%, as well as liver oxidative stress indicated by significantly increased SOD, CAT, and GSH-Px levels. Moreover, hepatic FXR activation and a corresponding downstream anti-oxidative stress transcriptional cascade including Nrf2, HO-1, and NOQ1 induce the protective role of BAN. On the other hand, BAN administration also leads to increase cellular autophagy response, as indicated by the key ATG protein activation. We concluded that BAN, comparing with Betulinic acid, prevents acute alcohol-induced liver damages more effectively, with the dual mechanisms of neutralizing oxidative stress and promoting autophagy.

Colorectal cancer (CRC) is one of the most common malignancies, giving rise to serious financial burden globally. This study was designed to explore the potential mechanisms implicated with CRC and identify some key biomarkers. CRC-associated gene expression dataset (GSE32323) was downloaded from GEO database. The differentially expressed genes (DEGs) were selected out based on the GEO2R tool. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were employed to search the enriched pathways of these DEGs. Additionally, a protein-protein interaction (PPI) network was also constructed to visualize interactions between these DEGs. Quantitative Real-time PCR (qPCR) was further performed to valid the top5 up-regulated and top5 down-regulated genes in patients with CRC. Finally, the survival analysis of the top5 up-regulated and top5 down-regulated genes was conducted using GEPIA, aiming to clarify their potential effects on CRC. In this study, a total of 451 DEGs were captured (306 down-regulated genes and 145 up-regulated genes). Among these DEGs, the top5 up-regulated genes were DPEP1, KRT23, CLDN1, LGR5 and FOXQ1 while the top5 down-regulated genes were CLCA4, ZG16, SLC4A4, ADH1B and GCG. GO analysis revealed that these DEGs were mainly enriched in cell adhesion, cell proliferation, RNA polymerase II promoter and chemokine activity. KEGG analysis disclosed that the enriched pathway included mineral absorption, chemokine signaling pathway, transcriptional misregulation in cancer, pathways in cancer and PPAR signaling pathway. Survival analysis showed that the expression level of ZG16 may correlate with the prognosis of CRC patients. Furthermore, according to the connectivity degree of these DEGs, we selected out the top15 hub genes, namely MYC, CXCR1, TOP2A, CXCL12, SST, TIMP1, SPP1, PPBP, CDK1, THBS1, CXCL1, PYY, LPAR1, BMP2 and MMP3, which were expected to be promising therapeutic target in CRC. Collectively, our analysis unveiled potential biomarkers and candidate targets in CRC, which could be helpful to the diagnosis and treatment of CRC.

The effects of interrupted aging on the microstructure, mechanical properties and corrosion resistance of Al–Cu–Mg–Ag heat-resistant alloy were investigated by hardness tests, tensile tests, exfoliation corrosion (EXCO) tests, transmission electron microscopy (TEM) and electrochemical analysis. Results showed some phases precipitated during the interrupted aging process in Al–Cu–Mg–Ag alloy, which were called secondary precipitations. The precipitations both in the grains and the grain boundaries were refined by interrupted aging. The phases on the grain boundaries of the single-aged sample were distributed discontinuously, whereas those of the interrupted-aged sample were chain-like with a wider precipitation free zone (PFZ) on both sides of the grain boundary. The elongation of Al–Cu–Mg–Ag alloy increased by 37.7% while the tensile and yield strength slightly decreased after interrupted aging. The corrosion resistance of Al–Cu–Mg–Ag alloy was mainly determined by the PFZ with the lowest self-corrosion potential. The coarse and discontinuously distributed precipitations on the grain boundaries of the single-aged sample gave rise to larger efficient PFZ width than that of the interrupted-aged sample, which then lead to wider corrosion passageway and resulted in the better exfoliation corrosion resistance of Al–Cu–Mg–Ag alloy treated by interrupted aging.

Zinc oxide (ZnO) is a wide direct band gap (3.37 eV) II-VI semiconductor material with a wide range of applications in light emitting devices, solar cells, field emission devices, gas sensors, etc. Over the past decades, metal oxide semiconductors have been investigated extensively for sensing various types of vapors and toxic gases. Among the various metal oxides for gas sensing applications, ZnO is one of the potential materials for high response, stability and sensitivity to volatile organic gases. At present, the ZnO-based gas sensor has a relatively high operating temperature. However, the stability and lifetime of gas sensors operating under high temperature conditions with a long term will be greatly reduced. In addition, the power consumption of gas sensors is also significantly increased. Furthermore, there can exist the potential of explosion when gas sensors are used to detect the flammable gases at high temperature. Therefore, it is necessary to improve the sensing properties and reduce the operating temperature of gas sensors. In this paper, ultra-long, large-sized Sb doped ZnO microwires are successfully prepared by using chemical vapor deposition. The gas sensor is based on the principle of non-balance electric bridge, and a single Sb doped ZnO microwire is used as a bridge arm R4 of non-balance electric bridge to produce a gas sensor that can work at room temperature. The results show that the response-recovery curves of sensors at the acetone and ethanol concentrations of 20 ppm, 50 ppm, 100 ppm and 200 ppm (1 ppm = 10–6) are rectangular at room temperature, and have stable current values in air and measured gas, and the response value of the device gradually increases with gas concentration increasing. Furthermore, the detection of acetone and ethanol gas reveal that the device has better selectivity for acetone gas. The response of the gas sensor to 200 ppm acetone is about 243%, with response and recovery time of 0.2 s and 0.3 s, respectively. Compared with the traditional resistive gas sensor, this non-balanced electric bridge sensor has high response, fast response and recovery time. In addition, the sensing mechanism of the device is also studied.

Cost reducing has always been a very important future development for Ti alloys. A new series of low cost TiZrAlFe alloys with ultra-high strength and favorable ductility are developed in this work. The microstructure and mechanical properties of the new series of low cost TiZr based alloys with Fe content from 0.5 to 2.0 wt% are investigated. As Fe content increases from 0.5 to 2.0 wt%, the β to α phase transition temperature decreases from 836 to 768 °C, and the phase constitution of the examined alloys changes from α′+β to αʺ+β and finally whole β phase. That acicular α′ martensite precipitating out of β matrix is the microstructural feature of the developed low cost alloy with Fe content of 0.5 wt%. As the Fe content increases to 1.0 wt%, the microstructural characteristic is some ultra-fine lenticular αʺ martensites with tens nanometers thickness enchased in β matrix. As the Fe content further increases to 1.5 wt%, the β grains generate recrystallization. Microstructural features of β grains further recrystallization and growth exhibit in the examined alloy with Fe content of 2.0 wt%. Tensile results show that the new series of low cost alloys have ultra-high strength and favorable ductility. The strength of the examined alloys changes from 1495 to 1212 MPa as the increasing of Fe content from 0.5 to 2.0 wt%. Meanwhile the total elongation ranges from 8.3% to 12.4%. The strengthening mechanism of the developed low cost TiZr based alloys is also discussed. The current finding not only presents an excellent alloy with superior combination of strength and ductility but promotes the development and application of low cost Ti alloys.

The effects of stress-aging on the microstructure and properties of Al–Cu–Mg–Ag alloy were studied by hardness test, electric resistivity test, optical microscopy and transmission electron microscopy. The results show that the application of external stress during aging did not change the grain morphology of Al–Cu–Mg–Ag alloy, but resulted in great changes of the precipitations. The precipitation of θ′ phases was promoted while that of Ω phases was restrained and the initial hardening rate of the alloy decreased. This might originate from the large amounts of dislocations during stress-aging that provided sites facilitating heterogeneous nucleation of θ′ phases. This was verified by the phenomenon that the density of θ′ phases increased while that of Ω phases decreased and the peak hardness was reduced when Al–Cu–Mg–Ag alloy was cold deformed with 6% stretch prior to aging.

The creep behavior of Al–Cu–Mg–Ag alloy and its microstructural evolution during creep deformation were studied at 100–210 °C with the external stress of 150–300 MPa. The results show that both Ω and θ ׳ precipitate secondarily in the under-aged sample during the creeping process, resulting in the excellent creep-resistant property compared to the peak aged sample. The temperatures between 100 and 150 °C have little affect on the creep curves of the alloy. The larger external stress led to the growth of the creep holes on the grain boundaries and the higher creep temperature led to the growth of the precipitations in the grains inner. They both result in the lower creep resistance of Al–Cu–Mg–Ag alloy. The steady creep rate increased with increasing creep temperature or external stress, which can be described by a constitutive equation with the creep deformation activation energy 102.00 kJ/mol.

ZnO and Fe-doped ZnO thin films were prepared by DC magnetron sputtering. The microstructure and optical properties of the two samples were compared and studied by atomic force microscopy (AFM), X-ray diffraction (XRD), UV–vis spectra and photoluminescence (PL) spectra. The results show that ZnO thin films were successfully prepared with smooth surface and preferred orientation growth, showing structure of single crystal. The surface and the crystal quality of ZnO thin film was improved when doped with Fe. And the average transmission decreased and the absorption edge red-shifted, which might be due to the formation of the defect level of Fe below the conduction band of ZnO. There were three photoluminescence peaks in ZnO thin films, one double ultraviolet peak at 370 nm and 410 nm and one blue peak at 466 nm, whose intensity all increased when doped with Fe. The peak at 370 nm originates from the transition emission of the electrons from the conduction band to the valence band; the peak at 410 nm is associated with electron transition from the conduction band to the V Zn level while the blue peak might be due to the intrinsic defect of Zn i .

The thermal stability of Al–Cu–Mg–Ag alloy was tested by thermal exposure and creep performance. The results show that the under-aged Al–Cu–Mg–Ag alloy possessed better thermal stability compared to the peak-aged one, due to the secondary precipitations of the strengthening phases. The number of the precipitations in the under-aged sample increased and then decreased with increasing the thermal exposure or creep time while that of the peak-aged sample decreased gradually. The tensile strength of the under-aged sample increased and then decreased with increasing the thermal exposure time with a peak value of 524 MPa after exposed for 20 h, which was 19 MPa higher than that of the peak-aged alloy. The steady creep rate of the under-aged sample was much lower and the creep-life was much longer to that of the peak-aged one, indicating that the under-aged sample possessed excellent creep resistance property at elevated temperatures.

The metallurgical composite bimetallic tube, Incoloy825/X60, has been manufactured by a novel centrifugal casting plus extrusion compound technique. Based on the Incoloy825/X60 bimetallic tube, the limiting inner pressure and stress distributions were investigated by the finite element analysis software ABAQUS. The results indicate that the pressure-resistant capacity of the metallurgical composite bimetallic tube is equivalent to the internal metal in elastic state while the limiting inner pressure is much larger than the single metal tube with the same sizes in plastic state. The pressure-resistant capacity of the metallurgical composite bimetallic tube has increased more than two times compared with the external metal tube because of the transition layer which has a complete metallurgical bonding.

Core/shell Fe3O4/BiOI nanoparticles with BiOI sheath have been synthesized by a solvothermal reaction method and were characterized by transmission electron microscopy (TEM) with an energy dispersive spectrum (EDS), high-resolution TEM and X-ray diffraction (XRD). Their photocatalytic activities were evaluated by methylene blue (MB) under the simulated solar light. The results indicate that the spherical Fe3O4 particles were coated with BiOI sheath when the sample were synthesized at 160 °C with ethylene glycol and deionized water, forming a core/shell structure. The degradation rate of MB assisted with the core/shell Fe3O4/BiOI catalysts reached 98 % after 40-min irradiation. The catalytic performance enhancement of the core/shell Fe3O4/BiOI catalysts mainly attributes to the band structure that can improve the generation efficiency, separation and transfer process of the photo-induced electron–hole pairs and decrease their recombination. The magnetic Fe3O4 core not only contributes to the efficient separation of electron and holes, but also helps catalysts be collected conveniently using a magnet for reuse. After five repeated trials, the degradation rate of MB still maintains over 90 % and the saturated magnetization of the catalysts remains 51.5 emu/g, which indicate that the core/shell Fe3O4/BiOI nanoparticles have excellent photocatalytic stability and are recyclable for decomposing organic pollutants under visible light irradiation.

ZnO thin films were prepared by DC magnetron sputtering. The effects working pressures on the microstructure, optical properties and the photoluminescent properties were studied. The results show that ZnO thin films were successfully prepared with preferred orientation growth, showing structure of single crystal. The transmission of all the ZnO thin films kept above 85%. With increasing the working pressure, the surface of ZnO thin film became coarse, the intensity of X-ray diffraction peak decreased and the transmission of the film decreased and then increased. The intensity of the two photoluminescence peak of ZnO thin films one ultraviolet peak at 400 nm and one blue peak at 466 nm increased with increasing the working pressure. The ultraviolet peak was originated from the transition emission of the electrons from the conduction band to the valence band while the blue peak was originated from the defects in ZnO thin films.

TiO2/(Ag) thin films were prepared by DC magnetron sputtering. The effects of Ag-doping on the microstructure and properties were compared studied by atomic force microscopy (AFM), X-ray diffraction (XRD), UV-Vis spectra and photocatalysis tesing, respectively. The results show that when doped with Ag, the surface of TiO2 thin film was improved and the growth of anatase phase was promoted. The absoption properties of Ag-doped TiO2 thin film was enhanced dramatically compared with that of TiO2 thin film. And the photocatalysis properties of Ag-doped TiO2 thin film was increased twice as well.

TiO2 and Ni-doped TiO2 thin films were prepared by DC magnetron sputtering. The effects of Ni-doping on the microstructure and properties were studied by atomic force microscopy (AFM), X-ray diffraction (XRD), UV-Vis spectra and photocatalysis tesing, respectively. The results show that TiO2 thin films were successfully prepared with smooth surface. When doped with Ni, the surface of TiO2 thin film was improved and the growth of anatase phase was also promoted. With increasing the sputtering power of Ni, the absorption edge wavelegth red shifted and the photocatalysis property of TiO2 thin films was increased and then decreased

Negative thermal expansion material ZrW2O8 was synthesized by hydrothermal method. The prepared ZrW2O8 and the precursor were characterized by x-ray diffractometer, thermo-gravimetric/differential thermal analyzer, FT-IR spectrometer and scanning electron microscope. The results show that a single-phase ZrW2O8 can be synthesized when HCl concentration is as low as 4mol/L. ZrW2O8 was obtained through the precursor dehydration and debonding O-H bond. The dehydration reaction includes two stages. There is a sharp endothermic peak in the first stage of the dehydration reaction and the second stage is a slow endothermic process. A new phase appeared when the sintering temperature is above 600 °C. ZrW2O8 and the precursor have the same rod-like shape and grow up along a specific direction. The synthesized ZrW2O8 particles obtained from 4mol/L HCl appeared large size. It became much finer and the rod with multiple crystal face was easy to form when the concentration of HCl increased to 6~8 mol/L.

This article uses the finite element software ABAQUS in the process of laser cladding to form the numerical simulation, which establishes numerical simulation model of the temperature field of laser cladding forming the heat transfer. The results show that the laser scanning position of the cladding layer depth direction of a high temperature gradient. Simulation of temperature changes of a known point the temperature change in laser scanning region is drastic. The experimental results show that the numerical simulation model of the temperature field is reasonable. Therefore, the numerical simulation model can be used to analyze the influence of the laser cladding parameters on the temperature field and simulate remelting depth under any scanning speed.

Based on the finite element analysis software ABAQUS, the CT specimens of bimetallic material and the metallurgical composite bimetallic pressure tube with axial crack were simulated on the fracture mechanical properties, after that the crack growth residual strength and the plastic failure stress of the metallurgical composite bimetallic pressure tube model were obtained. The results indicate that the crack growth residual strength generates near the crack tip and the crack growth residual strength of the pressure tube model is smaller than the CT specimens. Meanwhile, the plastic failure stress values obtained from the CT specimens and the pressure tube model are basically consistent with the theoretical calculative values. With the crack depth a increasing, the plastic failure stress values will be reduced. For the same crack depth, the plastic failure stress values of the pressure tube model are slightly lower than the CT specimens and the theoretical calculative values.

Gallium oxide (Ga2O3) has five crystalline polymorphs, i.e. corundum (α-phase), monoclinic (β-phase), spinel (γ-phase), bixbite (δ-phase) and orthorhombic (ε-phase). Among these phases, the monoclinic structured β-Ga2O3 is the most stable form, and is a ultraviolet (UV) transparent semiconductor with a wide band gap of 4.9 eV. It is a promising candidate for applications in UV transparent electrodes, solar-blind photodetectors, gas sensors and optoelectronic devices. In recent years, one-dimensional (1D) nanoscale semiconductor structures, such as nanowires, nanobelts, and nanorods, have attracted considerable attention due to their interesting fundamental properties and potential applications in nanoscale opto-electronic devices.Numerous efforts have been made to fabricate such devices in 1D nanostructures such as nanowires and nanorods. Comparing with the thin film form, the device performance in the 1D form is significantly enhanced as the surface-to-volume ratio increases. In order to realize β-Ga2O3 based nano-optoelectronic devices, it is necessary to obtain controlled-synthesis and the high-quality β-Ga2O3 nanomaterials. According to the present difficulties in synthesizing β-Ga2O3 nanomaterials, in this paper, the grid-like β-Ga2O3 nanowires are prepared on sapphire substrates via electric field assisted chemical vapor deposition method.High-purity metallic Ga (99.99%) is used as Ga vapor source. High-purity Ar gas is used as carrier gas. The flow rate of high-purity Ar carrier gas is controlled at 200 sccm. Then, oxygen reactant gas with a flow rate of 2 sccm enters into the system. The temperature is kept at 900℃ for 20 min. The effect of the external electric voltage on the surface morphology, crystal structure and optical properties of β-Ga2O3 nanowires are investigated. It is found that the external electric voltage has a great influence on the surface morphology of the sample. The orientation of the β-Ga2O3 nanowires grown under the action of an applied electric field begins to improve. Only a grid composed of three different growth directions appears. And with the increase of applied voltage, the distribution of nanowires becomes denser and the length increases significantly. In addition, it is found that the chemical vapor deposition method assisted by this external electric field can significantly improve the crystallization and optical quality of the samples.

To enhance the mechanical property and the bioactivity of composites, nano-hydroxyapatite (n-HA) modified monomer casting nylon-6 (n-HA/N) composites were prepared by in situ polymerization. During the synthesis of n-HA/N composite, the n-HA and caprolactam were mixed, melt and placed in the field of ultrasonic radiation. The differences between composite with ultrasonic and without ultrasonic were investigated. The tensile strength and the viscosity average molecular weight of the nylon matrix were measured. The results show that the molecular weight of the nylon matrix decreased firstly and it had the lowest value when the content of nano-hydroxyapatite was 1.6 wt.%. After that the molecular weight increased and then it began to decrease when it reached the highest value. But the tensile strength of the n-HA/N composite were improved. The ultrasonic dispersion made the n-HA more evenly dispersed in the nylon and increased the mechanical properties of the n-HA/N composites significantly. The bioactivity and moisture absorption of n-HA/N composites in simulated body fluid (SBF) were examined and compared to pure nylon. What's more, Fourier transform infrared spectrometer was used to characterize the structure of the materials formed on the surface of the composite. The results showed that moisture absorption of the n-HA/N composites was lower than that of the pure nylon. After composites impregnated 16 days in SBF, a layer of carbon hydroxyapatite (CHA) with weak crystalline was formed on the surface of sample. This phenomenon showed that the n-HA/N composites have good bioactivity.

Nano-Al2O3-reinforced monomer casting nylon (NA/MCN) composites were prepared by using in situ polymerization. The average molecular weight of the matrix nylon was measured using gel permeation chromatography. The thermal-mechanical properties of the NA/MCN composites were characterized by thermo-dynamic mechanical analysis, and the results were compared with micro-Al2O3-reinforced nylon (MA/MCN) composites. A tensile property test was conducted to investigate the mechanical properties of neat nylon and composites. Experimental results showed that the average molecular weight of the matrix nylon filled with nano-alumina had little change and was higher than that with micro-alumina. The glass transition temperature (Tg) and storage moduli of NA/MCN composites were higher than that of neat nylon. During the experiment, it was also found that the tensile strength increased up to 52% when 3 wt.% of nano-Al2O3 particles were added. The thermal and tensile properties of NA/MCN composites were better than those ...

Three-dimensional braided carbon fiber-reinforced nylon composites (C3D/MCN) were prepared in order to investigate the influence of oxidation of carbon fibers on the tribological properties of the C3D/MCN composites. Friction and wear tests of the C3D/MCN composites with untreated and treated carbon fabric were conducted. The characteristics of the carbon fiber, the interface strength, the hardness, and the worn surface morphologies of the C3D/MCN composites were analyzed. The results show that the specific surface area of treated carbon fiber was far higher than that of untreated carbon fiber and there formed a functional group of –C=O on the carbon fiber surface after air oxidation. The oxidation of the carbon fibers improved the interface strength between the carbon fibers and the matrix and had little effect on the hardness of the composites. The friction coefficient and wear rate of C3D/MCN composites with oxidized carbon fibers were apparently lower than those with untreated carbon fibers. In conclu...

A new type of material for orthopaedic devices, a three-dimensional braided carbon fiber-reinforced nylon 6 (C3D/MCN) composite, was prepared by anionic polymerization. It was characterized by using a block-on-ring wear tester equipped with real-time friction measurement capabilities. Scanning electron microscope and an optical microscope were used to study the wear surfaces of the composites and metallic ring counterpart. The effects of carbon-fiber volume fraction, braiding angle, and friction condition on the tribological properties and wear mechanism of C3D/MCN composites were observed. Experiments showed an optimum wear resistance when the carbon-fiber volume fraction was 35%. A lower wear rate was observed at higher braiding angle, as well as under Hank’s-solution-lubricated conditions. The wear mechanism under dry sliding conditions is adhesive wear and abrasive wear. The C3D/MCN composites exhibited mainly abrasive wear under Hank’s-solution-lubricated conditions.

To investigate the influence of carbon fiber oxidation on the tribological behavior of the 3D-braided carbon fiber/nylon composites (C 3D /MCN), C 3D /MCN composites were prepared. The characteristics of carbon fibers with different conditions were characterized. The mechanical property, friction and wear tests of the composites with untreated and treated carbon fabric were performed and the worn surface morphology and wear debris were analysed. The results show that the specific surface area of the treated carbon fiber was far higher than that of the untreated carbon fiber and there formed a functional group of –C O on the carbon fiber surface after air oxidation. The flexural strength, flexural modulus and shear strength of C 3D /MCN composites with oxidized carbon fiber fabric were improved. The friction coefficient and wear rate of C 3D /MCN composites with oxidized carbon fiber fabric were apparently lower than that with untreated carbon fiber fabric. In conclusion, the surface treatment favored the improvement of the higher interface strength and so had good effect on improving the tribological properties of the composites.

Nano-Al2O3 and micron Al2O3 reinforced polyamide 6 composites (PA6/Al2O3) were prepared via in situ polymerization. The effects of nano-particle content and wear condition on the tribological properties of the composites were measured using a MM-200 block on ring wear tester. The worn surface was investigated with a scanning electronic microscope and a metallurgical microscope and the wear mechanism was proposed. It was found that nano-Al2O3 improved the wear resistance of monomer casting polyamide 6 with the optimal content of nano-Al2O3 being approximately 3 wt.%. The wear rate of PA6/Al2O3 nano-composite was lower than that of the composite with micron Al2O3 and increased slowly while its friction coefficient decreased gradually with load. However, the friction coefficient of the composite was somewhat larger than that of monomer casting polyamide 6 and lower than that of the composite with micron Al2O3.

Here we reported that co-administration of docetaxel and a cell-permeable short-chain ceramide (C6) resulted in a striking increase in growth inhibition and apoptosis in primary and transformed breast cells (MCF-7 and MDA-231), which were associated with mitochondrial permeability transition pore (mPTP) opening, a significant reactive oxygen species (ROS) production and the pro-apoptotic AMP-Protein Kinase (AMPK) as well as c-Jun N-terminal kinases (JNK) activations. Contrarily, the mPTP blocker sanglifehrin A (SfA) or the ROS scavenger N-acetyl-l-cysteine (NAC) largely inhibited co-administration-induced cytotoxicity. Further, cyclosporin A (CsA), the inhibitor of cyclophilin-D (Cyp-D, the key mPTP component), as well as Cyp-D RNA silencing also suppressed breast cancer cell death by the co-treatment, while cells overexpressing Cyp-D showed hypersensitivity to docetaxel. Meanwhile, JNK and AMPK inhibition alleviated cell death induced by the co-administration in cultured breast cancer cells. Significantly, C6 ceramide plus docetaxel caused dramatic human epidermal growth factor receptor (HER)-1/-2 degradation and downstream Akt/Erk inhibition in HER-2 expressing MDA-231 cells. These in vitro findings provide confidence in support of further development of C6 ceramide as an adjunct of docetaxel for the treatment of the metastatic breast cancer.

Background Pancreatic cancer is one of the most aggressive human malignancies with a extremely low 5-year survival rate. Hence, the search for more effective anti-pancreatic cancer agents is urgent. Methods PaTu8988 pancreatic cancer cells were treated with different concentrations of suberoylanilide hydroxamic acid (SAHA), cell survival, proliferation, migration and vasculogenic mimicry (VM) were analyzed. Associated signaling changes were also analyzed by RT-PCR and Western blots. Results Here, we reported that SAHA, a histone deacetylase inhibitor (HDACi), exerted significant inhibitory efficiency against pancreatic cancer cell survival, proliferation, migration and VM. SAHA dose-dependently inhibited PaTu8988 pancreatic cancer cell growth with the IC-50 of 3.4 ± 0. 7 μM. Meanwhile, SAHA suppressed PaTu8988 cell cycle progression through inducing G2/M arrest, which was associated with cyclin-dependent kinase 1 (CDK-1)/cyclin-B1 degradation and p21/p27 upregulation. Further, SAHA induced both apoptotic and non-apoptotic death of PaTu8988 cells. Significantly, SAHA suppressed PaTu8988 cell in vitro migration and cell-dominant tube formation or VM, which was accompanied by semaphorin-4D (Sema-4D) and integrin-β5 down-regulation. Our evidences showed that Akt activation might be important for Sema-4D expression in PaTu8988 cells, and SAHA-induced Sema-4D down-regulation might be associated with Akt inhibition. Conclusions This study is among the first to report the VM formation in cultured human pancreatic cancer cells. And we provided strong evidence to suggest that SAHA executes significant anti-VM efficiency in the progressive pancreatic cancer cells. Thus, SAHA could be further investigated as a promising anti-pancreatic cancer agent.

Ti(C,N)-based cermets were coated with a TiN/TiAlN coating using ion plating technology. The sliding wear test was performed for the coated cermets and the microstructure, composition and surface roughness of the coated cermets under different velocities and loads were characterized. The results showed that the friction coefficients of the coated cermets were lower than that of the neat cermets. Under the same load, the adhesion phenomenon of the counterpart materials on the specimens was improved and the mean friction coefficient increased with increasing sliding speed. Under the same sliding velocity, the average friction coefficient of the coated cermets was lower under higher load. The wear mechanisms were mainly adhesive wear and abrasive wear.

In order to decrease the heat-treatment time and avoid particle growth during the post-sintering heat-treatment, the interaction of nitrogen with (Ti,W)(C,N)/(Ni,Mo) cermets was investigated at high pressure. Sintered (Ti,W)(C,N)/(Ni,Mo) cermets with different starting formulations were heated at 1000 °C using nitrogen pressures up to 110 MPa. At this temperature and nitrogen pressure the nitriding time for the formation of interaction zones more than 20 μm thick is decreased to 3 hours and no particle growth occurs. The heat-treatment leads to a dramatic improvement in surface hardness and a very small decline in transverse rupture strength of the (Ti,W)(C,N)/(Ni,Mo) cermets. The microhardness in the near-surface area shows a transition of the highest microhardness to a lower as the interior is approached.

To study the relationship between status of methylation of human runt-related transcription factor 3 (RUNX3) gene promoter in papillary thyroid carcinoma (PTC).Methylation-specific PCR and immunohistochemical SP technique were used to detect the methylation of RUNX3 gene promoter and expression of its protein in 56 cases of PTC and their matched adjacent non-carcinous epithelium (NCE).In NCE, there was no methylation of RUNX3 gene promoter, while in PTC the methylation rate was 35.7%(20/56), which was related to the tumor TNM stage, pathological grade and lymph node metastasis (P0.05). The positive rates of RUNX3 protein expression in NCE and PTC were 100.0% and 60.7%, respectively, with a significant difference (χ(2) = 27.378, P0.05). In PTC, the positive rates of RUNX3 protein expression in gradeI and grade II were 70.0% and 37.5%, respectively (P0.05); the rates were 46.7% and 76.9% in lymph node metastasis group and no metastasis group, respectively (P0.05). Moreover, there was a distinct correlation between methylation of RUNX3 gene promoter and expression of its protein (χ(2) = 21.62, P0.01).Methylation of promoter might be one of the important factors of inactivation of RUNX3 gene, and might play an important role in carcinogenesis and progression of PTC.

To explore the mRNA and protein expressions of Runx3 gene in papillary thyroid carcinoma (PTC).Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the Runx3 mRNA and protein levels in 67 human PTC specimens and their matched adjacent non-cancerous epithelium (NCE).The relative expression value of Runx3 mRNA was 0.31 ± 0.07 in PTC versus 0.92 ± 0.08 in NCE (t = 38.251, P0.05). In PTC, it was correlated with the tumor pathological grade and lymph node metastasis (χ(2) = 5.511, 6.492, P0.05). The integral optical density value of Runx3 protein confirmed was 1012 ± 221 in PTC versus 1993 ± 199 in NCE (t = 18.413, P0.05). In PTC, it was correlated with the tumor TNM stage, pathological grade and lymph node metastasis (χ(2) = 5.550, 9.678, 5.070, P0.05). Furthermore there was a distinct correlation between the mRNA and protein expressions of Runx3 gene (χ(2) = 42.699, P0.05).The mRNA and protein expressions of Runx3 gene in PTC were lower than those in NCE. A lower expression of Runx3 gene may play an important role in the carcinogenesis and progression of PTC.

Objective: Coxsackievirus B3 (CVB3) is a dominant causative agent for viral myocarditis. So far, effective therapies for the treatment of the disease are not available. 20(S)-Protopanaxtriol is a major component of Panax pseudoginseng and has been clinically used for the treatment of heart diseases. However, it is not known whether 20(S)-protopanaxtriol exerts any anti-viral effects. Thus, the aim of this study was to investigate the therapeutic effects of 20(S)-protopanaxtriol against CVB3 in vivo and in vitro. Methods: The antiviral effects of 20(S)-protopanaxtriol in vitro were evaluated in HeLa cells infected by CVB3. Then, we examined the protective effects of 20(S)-protopanaxtriol on CVB3-induced myocarditis in BALB/c mice. These mice were treated with 20(S)-protopanaxtriol at doses of 100–400 mg·kg–1·day–1 for 7 days and compared with the controls. Results: We found that 20(S)-protopanaxtriol possessed potent antiviral effects on CVB3 in vitro. Compared with control mice, virus titers and pathological changes in the hearts were significantly decreased in the 20(S)-protopanaxtriol-treated group. Furthermore, biochemical markers of myocardial injury such as plasma lactate dehydrogenase and creatine kinase were decreased to normal levels. Conclusions: These data provide the possibility that 20(S)-protopanaxtriol can be used as a potential therapeutic means for treatment of viral myocarditis.