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BACKGROUND: Alzheimer’s disease (AD) is a major cause of dementia, which is a growing global health problem and has a huge impact on individuals and society. As the modifying role of geniposidic acid (GPA) has been suggested in AD, this study sets out to determine if and how GPA treatment affects AD progression in mice. METHODS: Potential downstream target genes of GPA during AD were identified by bioinformatics analysis, revealing GAP43 as a primary candidate protein. Then, mPrP-APPswe/PS1De9 AD transgenic mice were treated with GPA via intragastric administration. This allowed for gain- and loss-of-function assays of candidate proteins being carried out with or without GPA treatment, after which behavioral tests could be conducted for mice. Cortical neuron apoptosis was measured by TUNEL staining, Amyloid β-protein (Aβ) expression in cerebral cortex by Thioflavin-s staining, and Aβ, IL-1β, IL-6, IL-4 and TNF-α levels in cerebral cortex by ELISA. GAP43 expression in cerebral cortex of mice was detected by immunohistochemistry. Primary cortical neurons of embryonic mice were isolated and induced by Aβ1-42 to construct AD cell model. Cell viability was assessed by CCK-8, and axon growth by immunofluorescence. RESULTS: GPA administration significantly improved the cognitive impairment, reducing Aβ accumulation and neuronal apoptosis in AD mice, and alleviated inflammation and axonal injury of Aβ1-42-induced neurons. GAP43 was shown experimentally to be the target of GPA in AD. Silencing of GAP43 repressed the neuroprotective effect of GPA treatment on AD mice. GPA elevated GAP43 expression via PI3K/AKT pathway activation and ultimately improved nerve injury in AD mice. CONCLUSION: GPA activates a PI3K/AKT/GAP43 regulatory axis to alleviate AD progression in mice.

The trade-off relation between the strength and the electrical conductivity has been a long-standing dilemma in metallic materials. In the study, three key principles, i.e. elongated grains, sharp texture and nano-scale precipitates, were presented for preparing Al wire with high strength and high electrical conductivity based on the specially designed experiments for breaking the mutually exclusive relation between the strength and the electrical conductivity. The results show that the elongated grains could lead to a higher electrical conductivity in Al wire without sacrificing the strength; while, the sharp texture can efficiently strengthen the Al wire without influencing the electrical conductivity. Furthermore, nano-scale precipitates with proper size can simultaneously improve the strength and electrical conductivity of Al alloy wire. Under the guidance of the above three key principles, Al wires with high strength and high conductivity were prepared.

The evolution of microstructure in the drawing process of commercially pure aluminum wire (CPAW) does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CPAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CPAW under axial loading.

Strength degradation during the electron transmission process is always a hidden danger to the overhead transmission lines. In this study, the microstructure evolutions and the strength degradation behaviors of a cold-drawn commercially pure Al conductor (CPAC) were investigated systematically by a series of annealing experiments. The results show that the texture evolution, dislocation recovery and subgrain growth during the recrystallization should be responsible for the strength degradation of CPAC. Besides, the microstructure evolution depends on the annealing temperature. For instance, some of the texture was changed into the one in the CPACs annealed at a temperature of 90 °C; while, there is an obvious increase in the subgrain width when the CPACs were annealed in the high temperature range from 150 °C to 300 °C. Finally, the strength degradation due to the texture evolution and the subgrain coarsening was quantitatively calculated based on the crystallographic analysis.

The degradation characteristic of GaInP/GaAs/In0.3Ga0.7As inverted metamorphic (IMM) triple junction solar cells irradiated by 1 MeV electron and 10 MeV proton have been studied and compared to that of traditional GaInP/InGaAs/Ge lattice matched (LM) triple junction solar cells. Both IMM and LM solar cells exhibited very good radiation resistance upon 3.16 × 1010 MeV/g displacement damage dose electron and proton irradiation level. The remaining factor of maximum output power is 0.86 and 0.85 for electron irradiation and 0.73 and 0.75 for proton irradiation in IMM and LM solar cells, respectively. IMM solar cell showed better properties in current matching in end-of-life condition comparing to that of LM solar cells. 1 MeV electron to 10 MeV proton irradiation relative damage coefficients, R e p , for IMM and LM solar cells are determined as 3.11 and 2.78, respectively, by using equivalent displacement damage dose model. The radiation damage coefficient of diffusion length upon 1 MeV electron and 10 MeV proton irradiation for both types of solar cell structures have been calculated.

Excellent strength and electrical conductivity are of great significance for Al wires applied to overhead transmission lines, since the strength and the electrical conductivity are mutually exclusive. In this paper, the strength-electrical conductivity relation of an Al-1.13 wt% Fe wire fabricated by cold drawing process was investigated by means of microstructure characterization, tensile test, electrical test and theoretical calculation. At the initial stage of the cold-drawing deformation, the strength and the electrical conductivity exhibit a traditional trade-off relation. Surprisingly, the strength-electrical conductivity relation turns to be abnormal as the area reduction exceeds a critical value, 61.9%. The particular phenomenon can be well explained by the formation of the elongated grains. Additionally, the Fe-contained nano-scale precipitates together with the low solubility of Fe element also have an outstanding contribution to the strength and the electrical conductivity of Al–Fe alloy wire. Consequently, the elongated grains, the 〈111〉 texture, the low solubility and the nano-scale precipitates are proposed as four mechanisms for designing and preparing high strength-high electrical conductivity Al wire.

FeSe exhibits a novel ground state in which superconductivity coexists with a nematic order in the absence of any long-range magnetic order. Here, we report on an angle-resolved photoemission study on the superconducting gap structure in the nematic state of FeSe_{0.93}S_{0.07}, without the complications caused by Fermi surface reconstruction induced by magnetic order. We find that the superconducting gap shows a pronounced twofold anisotropy around the elliptical hole pocket near Z (0, 0, π), with gap minima at the end points of its major axis, while no detectable gap is observed around Γ (0, 0, 0) and the zone corner (π, π, k_{z}). The large anisotropy and nodal gap distribution demonstrate the substantial effects of the nematicity on the superconductivity and thus put strong constraints on current theories.

Al(x)In(1-x)N films with an AlN buffer were deposited on different substrates (including Si(1 1 1), sapphire, and glass) by radio-frequency (RF) magnetron sputtering at a low temperature of 300 degrees C. The morphology and structure analysis revealed that the Al(x)In(1-x)N films grown on Si(1 1 1) and sapphire are of high orientation and good crystallinity with a bandgap energy (E(g)) of less than 2.41 eV. The sheet resistance of Al(x)In(1-x)N film grown on Si(1 1 1) and sapphire is approximately 40 Omega/square. These results are highly relevant to the development of effective nitride photovoltaic materials. (C) 2009 Elsevier B.V. All rights reserved.

The electronic structures and optical properties of wurtzite InxAl1−xN have been calculated using a first-principles self-consistent method. The calculated lattice constants and band gap bowing parameter are in good agreement with the experimental results and/or values given by other calculation methods. It is interestingly found that the peaks of total density of states (TDOS) in the conduction band have a tendency of shifting to the lower energy as In concentration increases in InxAl1−xN; while in the deep valence band, the peak splits into three peaks. The optical properties such as the dielectric function, reflectivity, absorption coefficient, refractive index, and electron energy-loss function are also presented. The main peak in imaginary part of dielectric function spectrum, the absorption edge and the peak in L(ω) spectrum are found to have a remarkable red-shift as In mole fraction increases. Furthermore, the optical properties of wurtzite InxAl1−xN are discussed based on the band structures and density of states (DOS) analysis.

The effect of different hydroxyapatite particles on malignant melanoma cell was evaluated in vitro. Two kinds of short-rode hydroxyapatite particles, which range from 0.4 to 1 um and 0.5 to 1.5 um, were co-cultured with human’s malignant melanoma (MM) cell line A375 for 24, 48, and 72 h. Both of these HA particles showed the same cell proliferation rate as blank control, and there was no statistically significant correlation of matrix metalloproteinases-2 (MMP-2) expression to the HA particle size. SEM images showed that the membrane of tumor cell, which co-cultured with HA particles, was shrunk. The cell superficial sentus was reduced and small size particle’ effect was more obvious. Since immunohistochemistry and SEM data are qualitative technique, further precise methods might bring more information about the effect of HA particles on tumor behaviors. But this study can provide the bio-security test of micrometer HA particles in transplantation after tumor excision.

In design of aqueduct structure, natural frequency calculation is the basis of earthquake response analysis. In this paper, the dynamic characteristic of Gegou U shape aqueduct is calculated by the finite element software ANSYS. And in this software, the interaction between water and aqueduct wall is simulated with added mass method. Natural vibration frequencies and principal modes of Gegou U shape aqueduct are analyzed and calculated in four different water level which include empty tank water level, semi tank water level, design water level and bank-full water level. The calculation results show that the water level has a great influence on the natural frequencies of the aqueduct and the frequencies decrease with the increase of water level. The research results can provide basis for its protection and seismic design of U shape aqueduct. Keywords-Gegou aqueduct; ANSYS; natural frequency; vibration mode; added mass

In this paper, the finite element method was used to analysis the modal characters of a reinforced concrete pedestrian bridge structures. The relationship between parameters and structural vibration frequency was found by parametric analysis. Structural dynamic conditions corresponding state occurred was mainly determined by main modes. In practice, simulated operation, bridges can be analyzed by the previous stage of the natural frequencies and the mode shapes in order to assess. Keywords-pedestrian bridge; modal analysis; dynamic characteristics; natural frequencies; mode shapes

The controversial pinning dependence of the Hall conductivity ( σ xy ) is studied in the vortex-liquid phase of high- T c superconducting thin films. A strong pinning dependence of σ xy is found to be triggered by a crossover from a regular liquid to the glassy liquid (GL) where vortices remain coupled in ab -plane. This result suggests that a non-linear effect in the GL region needs to be considered to account for the behavior of σ xy in the whole vortex-liquid phase.

The Ordovician strata is dominated by carbonate rocks in the Chenghai buried hill of Dagang exploration area in the east of China, with fractures and vugs as reservoir space, and strong heterogeneity. Big in buried depth and complex in geological conditions, it is very difficult to effectively predict the fractures and vugs in the plan distribution with any single prediction method, so it is necessary to use various methods from multiple points of view to confirm each other in the research into Ordovician reservoirs. In view of this, the method combining coherence analysis and seismic pixel processing has been applied to predict favorable fracture zone from different views for the buried hill, and a variety of seismic techniques are used to comprehensively analyze the prediction results, comprehensive evaluation plan of fracture prediction of the upper strata of Ordovician has been finished, and fracture developed areas identified, improving the reliability of prediction and providing an important basis for exploration decision.

Treatment modalities are not effective once breast cancer metastasis has occurred. Dietary botanicals may have a better protective effect. We therefore investigated the effects of grape skin polyphenols on a highly metastatic mouse mammary carcinoma cell line. In vitro treatment of 4T1 cells, with grape skin polyphenols resulted in inhibition of the migration and viability in a dose-dependent manner. The migration of 4T1 cells was significantly inhibited by grape skin polyphenols, even at a very low concentration (5 μg/ml), and was totally inhibited when the concentration was 20 μg/ml. However, 20 μg/ml of grape skin polyphenols inhibited cell viability by only 11.4%. The inhibition of migration is independent of decreased cell viability or apoptosis induction. Further analysis indicated that the inhibition of migration by grape skin polyphenols is involved in blocking the PI3k/Akt and MAPK pathways. The effects of dietary grape skin polyphenols were then examined using an in vivo model in which 4T1 cells were implanted subcutaneously in Balb/c mice. The metastasis of tumor cells to the lungs was inhibited significantly by dietary grape skin extracts (0.5 and 1.0 mg/ml in drinking water) and the survival of the mice enhanced. These data suggest that grape skin polyphenols possess chemotherapeutic efficacy against breast cancer with metastases.

We review the growth and field emission (FE) properties of ZnO, ZnS, and GaN nanostructures. For ZnO nanostructures, we discuss in detail solution-based growth techniques and the effects of residual gas exposure on the FE properties. We present new results showing that O2 and CO2 exposures do not have a significant effect on the FE properties of ZnO nanorods, but N2 exposure significantly degrades them. We also present new results showing that Cs deposition significantly improves the FE properties of GaN nanorods.

Tests have shown that ordered intermetallic compounds favor planar slip and tend to have no cross-slip or multi-slip. This was explained by the long Burger's vector in these ordered compounds. The flow stress of the ordered has been found to be less than that of the disordered ones. However the high-cycle fatigue life of the ordered was found to be significantly more than that of the disordered. This is believed to be due to low rate of crack initiation. Cracks have been found to initiate exclusively at slip bands extrusions and intrusions in intermetallic compounds. This paper shows a micromechanic fatigue model. This model was used to calculate the extrusion growth of a single fatigue band and then multiple fatigue bands in the most favorably oriented crystal. It was found that extrusion growth in the ordered alloy is significantly less than that in the disordered ones. The S−N curves to give given plastic shear strains of the extrusion at the free surface were calculated for both the ordered and disordered alloys. It was found that the ordered alloy has significantly higher S−N curves as observed in experiments.

SUMMARY The opening of fatigue crack increases the tip radius and the closing of the crack decreases it. This variation of the tip radius changes the stress intensity and has effect on crack tip closure, and hence affects the fatigue life. Two numerical examples are given to show this geometrical nonlinearity effect.

Uptake and conjugation of sulfate was studied in isolated kidney tubule fragments of rats: Sulfate is rapidly taken up, and maximal cellular concentrations are attained after 5-10 min; intracellular steady-state levels depend on the sulfate concentrations of the medium and attain a maximal value at 2 mM. At 1 mM sulfate in the medium the ratio of intracellular/extracellular concentrations of the inorganic anion amount to about 0.25. Formation of 7-hydroxycoumarin sulfate increases almost linearly up to an extracellular sulfate concentration of 500 microM. Thereafter, rates of sulfation increase more slowly and maximal sulfation rates are attained at 2 mM sulfate. The data indicate that sulfation of 7-hydroxycoumarin proceeds at almost maximal rates in kidney tubule fragments at physiological serum sulfate concentrations.