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• The strength of focus sextuple for uniformization have been obtained in mathematical. • The alpha magnet with 270° bending angle has been first successfully commissioning. • The focus sextuple has been first manufactured and successfully commissioning. • The beam line is simulated and the perfect uniformization result has been obtained. • The beam spot of 800mm×800mm is obtained with the uniformization better than 90%. We have commissioned a multiple-energy electron accelerator that illuminates an 800 mm × 800 mm target. The energy of the beam ranges from 0.5 to 5 MeV. A beamline following the accelerator has horizontal and vertical sections that include an alpha dipole and a "focus sextupole". In the horizontal section, the alpha magnet, having a bend angle of 270° and a field index of 0.8, provides both vertical collimation and energy selection. In the vertical section, a focus sextupole converts the initial Gaussian beam distribution to a uniform distribution in one dimension without beam loss. We used a scanning magnet just ahead of the target to expand the beam in the orthogonal dimension. Using the French code TraceWin, we simulate the beam dynamics in this beamline by integrating electron trajectories through field maps of the magnets. We have determined experimentally that the focus sextupole creates a horizontal strip beam on target having a current density uniformity of better than 90 %. By scanning this strip beam vertically, we have achieved a two-dimensional current density uniformity of better than 90 %. [ABSTRACT FROM AUTHOR]

The detection of glucose plays a critical role in the areas of clinical diagnosis, food analysis, and biotechnology. Here, a MoS 2 mircoflower based non-enzymatic glucose sensing strategy was suggested. The MoS 2 microflowers were synthesized by hydrothermal method using cetyltrimethylammonium bromide (CTAB) as surfactant and fabricated a non-enzymatic glucose biosensor. The experimental results showed that the prepared MoS 2 were flower-like microstructures. Moreover, when pH = 8, concentration of CTAB is 16 mM, and annealing temperature is 500 °C, the MoS 2 microflowers is more suitable to fabricate electrode. Electrochemical tests showed that the electrode exhibited synergistic electrocatalytic activity with a high sensitivity of 570.71 μA mM −1 . A good linear relationship between the anodic peak current and glucose concentration was obtained in the range from 0 to 30 mM. This work puts the flower-like MoS 2 materials into application as the electrochemical sensing platform for non-enzymatic glucose detection. [ABSTRACT FROM AUTHOR]

Objective: Leptin has been found highly expressed in human osteoarthritis. We aimed to explore the possible effects and mechanisms of leptin on the apoptosis and autophagy of chondrocytes during osteoarthritis pathogenesis.Methods: Gene expression profile from osteoarthritis affected and preserved cartilage were downloaded from NCBI's Gene Expression Omnibus database (GSE57218). Lysyl oxidase-like 3 (LOXL3) mRNA expression in cartilage tissues and leptin concentration in joint synovial fluid (SF) was measured in samples from 45 osteoarthritis patients and 25 healthy donors by real-time PCR and radioimmunoassay, respectively. Rat osteoarthritis model was induced by anterior cruciate ligament transection (ACLT). The expression of apoptosis regulators and autophagy markers were detected by Western blot. Cell survival and cell apoptosis were identified by CCK-8 and flow cytometry, respectively.Results: Re-analysis on GSE57218 indicated that LOXL3 mRNA was upregulated in osteoarthritis affected cartilage. LOXL3 mRNA was upregulated in osteoarthritis patients, which was positively correlated with SF leptin concentration. Similar results were obtained in rat osteoarthritis model. Moreover, ACLT surgery led to a significant increase in the protein levels of cleaved caspase 3, and a notable decrease in the protein levels of Bcl-2, LC3 II/LC3 I and Beclin1. Silencing of LOXL3 in ACLT and leptin treated primary chondrocytes significantly inhibited cell apoptosis, and promoted cell proliferation and autophagy. Moreover, overexpression of LOXL3 remarkably inhibited autophagy of chondrocytes via activating mTORC1.Conclusions: LOXL3, a downstream of leptin, stimulated the apoptosis, but inhibited the autophagy of chondrocytes. LOXL3 is a potential therapy target for osteoarthritis. [ABSTRACT FROM AUTHOR]

Effects of trace elements (0.2Y and 0.2Ca (wt%) on the eutectic Ge in high purity Al–20Ge (wt%) alloys were investigated by multi-scale microstructure characterization techniques. Particularly, the distribution of trace elements (Y and Ca) within the eutectic Ge and/or at the interface between eutectic Ge and eutectic Al was investigated by atomic resolution high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) imaging and atom probe tomography (APT). The combined investigations indicate Al–Y and Al–Ca co-segregations. Such co-segregations change significant morphology and growth of the eutectic Ge. In addition, large Al 2 Ge 2 Y and Al 2 Ge 2 Ca phases were also measured. The modification of eutectic Ge is discussed in terms of previously postulated modification mechanisms: twin plane re-entrant edge growth mechanism, impurity-induced twinning, and growth restriction of eutectic Ge. [ABSTRACT FROM AUTHOR]

Cracking is a major concern in the long-term performance of landfill clay liners. Cracking of clay liners is affected by the roots of the vegetation planted to control erosion. While vegetation roots may restrict cracking they may introduce preferential flow through the liners. The impact of vegetation roots on the hydraulic properties of clay liners remains unclear. This study investigates the effect of vegetation roots on crack formation and preferential flow through clay liners. Three experimental soil columns were used to observe crack formation by exposure to the weather and to measure the flow through them caused by artificial rainfall. The clay in each column was compacted to 90% relative compaction. The first column was not vegetated and no crack developed in it. The second column was vegetated and underwent drying–wetting cycles outdoor. The third column did not have vegetation but underwent drying–wetting cycles outdoor. Cracks developed in the second and third columns due to the exposure to the weather. Image analysis in the experimental soil columns revealed that vegetation roots restricted crack formation, especially in the early stages of drying–wetting cycles. Infiltration tests performed on the experimental soil columns showed that the unsaturated hydraulic conductivity of the vegetated soil in the second column was respectively about two orders and one order of magnitude larger than those of the soils in the first and third columns. The experimental results imply that the effect of vegetation roots on the preferential flow through landfill clay liners should be considered in practical designs. [ABSTRACT FROM AUTHOR]

Spudcans are large diameter (~ 20 m) conical foundations holding up mobile jack-up platforms for offshore oil and gas developments in shallow to moderate water depths. During self-installation the spudcan often penetrates several tens of meters into seabed soils, where large variations often occur in the shear strength of the soils. Although the failure mechanisms and bearing capacity of spudcan foundations have been studied in homogeneous soil and layered uniform soil, the effect of the spatial variability in soil strength on the spudcan response is still unclear. This study presents a random finite element method (RFEM) for assessing the failure mechanisms and the bearing capacity of a spudcan foundation embedded in spatially varied seabed soils. A comprehensive review of seabed soils discusses typical ranges of the mean, the coefficient of variation and the scale of fluctuation of the undrained shear strength. Random fields are generated and mapped into a non-linear finite element analysis to reveal the failure mechanisms of the spudcan in spatially varied soils. The influence of the scale of fluctuation in different directions is investigated. The results indicate that ignoring the spatial variability of soil strength leads to an overestimation of the bearing capacity. It is unconservative for the foundation design to assume an isotropic random field model in the RFEM analysis. [ABSTRACT FROM AUTHOR]

Mg–5Zn–2Gd–0.4Zr alloy (wt. %) shows a significant age hardening response with a hardness increment from 62 HV to 72 HV by ageing at 200 °C for up to 80 h. Transmission electron microscopy and atom probe tomography characterizations reveal that precipitates with different morphologies and habit planes form in the alloy, including triangular-shaped ZnZr phase, rectangular-shaped Zn 2 Zr phase, [0001] Mg rods ( β ′ 1 ) MgZn 2 Laves phase, (0001) Mg plate ( β ′ 2 ) MgZn 2 Laves phase, and coherent GP zones. Furthermore, a significant partitioning of Gd into Zn-rich precipitates ( β ′ 1 and β ′ 2 ) was, for the first time, observed, which is considered to be responsible for improving the thermal stability of Zn-rich precipitates and enhancing the precipitation hardening of the alloy. A core–shell structure with the shell of Gd (∼2 at%) and the core of Zn 2 Zr phase was also observed, which is proposed to hinder the coarsening of Zn 2 Zr phase. No further change in average size of the Zn 2 Zr particles was observed after ageing over 15 h. Better understanding the partitioning of Gd into the Zn-rich precipitates and the formation of the core–shell structures are essential to control the precipitation microstructure and develop high performance Mg alloys. [ABSTRACT FROM AUTHOR]

The limit analysis and the finite element method are powerful tools for analysing the bearing capacity of foundations. Previous research mainly focused on the foundations in uniform soils. In realistic conditions, soil properties are always varying spatially due to complex physical, chemical, and biological process in earth evolution. This paper investigates the bearing capacity and failure mechanism of footings buried at various depths in clays with spatially variable distribution of undrained shear strength using the lower bound limit analysis, the upper bound limit analysis, and the finite element analysis. Results show that the bearing capacity increases with increasing buried depths in spatially random soils, which is the same as in the uniform soils. The bearing capacity factors calculated using the finite element method, the lower bound limit analysis, and the upper bound limit analysis for a footing in spatially varied soils are all smaller than the corresponding values in uniform soils. The majority of the bearing capacity factors obtained from the finite element method is bounded by those obtained from the lower bound and the upper bound limit analysis. The shear planes show a clearly unsymmetrical manner in spatially varied soils using the three methods, which is different from the symmetrical shear plane in uniform soils. [ABSTRACT FROM PUBLISHER]

We consider the squeezing of output field in a two-mechanical-mode optomechanical cavity, which contains a Kerr-down conversion nonlinear crystal. It is found that the squeezing magnitude of the output field is enhanced by injection of the optical parametric amplifier (OPA) and the Kerr medium, and the squeezing region is shifted with the Kerr parameter. When the frequencies of the two movable mirrors are set by different values, the sharp peak with high contrast due to excess noise from thermally occupied mechanical mode will be split into two parts, which are located at the frequencies of the movable mirrors. This can be applied to high precision measurement of the frequencies of the mechanical oscillators. Finally, we consider the influence of the environment temperature on the squeezing spectrum. This is helpful in generating controllable squeezing in the optomechanical system by using nonlinear media. [ABSTRACT FROM AUTHOR]