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The microstructural features and crystallographic texture of 316L stainless steel prepared by direct energy deposition (DED) are studied. The grain size, morphology, grain boundary, misorientation distribution along different direction and mechanical properties are characterized via detailed electron backscatter diffraction (EBSD) analysis and Vickers microhardness tester. The DED-built 316L stainless steel exhibits equiaxed cellular and elongated morphology. Only a few number of dislocations are accumulated and entangled near small grain boundary. The sample contains mainly large angle grain boundary. 316L stainless steel powder is melted to form a deep and shallow shape measured from the top view. The average grain size is 38.32 µm and 29.79 µm for the top and side view, respectively. Two strong textural components of {001}<100> cube texture and {110}<001> Goss texture are formed perpendicular and parallel to the scanning direction, respectively. The microhardness of DED-built 316L stainless steel achieves a higher average value of 261.74 HV. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the mechanism of propofol in alleviating neuronal oxidative damage. MATERIALS AND METHODS: The neuron cells were randomly assigned to normal group (NOR), model group (MOD), and propofol administration group (MED). A 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was carried out to detect the viability of neuron cells, reverse transcription PCR (RT-PCR) assay to determine the gene expression of Fis and Mfn1, and Western blot assay to determine the protein expression of Caspase-3, Caspase-9, Bax, Bcl-2, and COX-2. RESULTS: According to the results of cell proliferation rate, under normal circumstances, neuron cells would have some programmed death and weak apoptosis, while after hypoxia-reoxygenation, the apoptosis rate of neuron cells gradually increased with the increase of culture time, which was significantly higher than that of the NOR. After the addition of propofol, the overall apoptosis rate of neuron cells slowly increased, significantly lower than that in the MOD and close to that in the NOR. Compared with the NOR, the ROS content in the MOD was significantly reduced, and compared with the MOD, the ROS content in the MED significantly recovered. Furthermore, the RT-PCR results showed that compared with the NOR, the expression of mitochondrial fusion protein (Mfnl) in the MOD group declined significantly, and the expression of mitochondrial fission protein 1 (Fis1) increased significantly, while after the addition of propofol, the expression of Mfnl and Fis1 was closed to that in the NOR. WB results showed that compared with the NOR, the expression of apoptosis proteins (Caspase-3, Caspase-9, Bax, and COX-2) in the MOD increased significantly, and the expression of Bcl-2 reduced significantly (all p<0.05), and the addition of propofol improved the expression of corresponding proteins. CONCLUSIONS: Propofol could alleviate hypoxic neuronal injury by inhibiting high levels of mitochondrial fusion and fission. [ABSTRACT FROM AUTHOR]

Rare earth (RE) ions (Eu3+,Tb3+) doped uniaxially aligned HfO2 nanotubes were prepared by radio frequency sputtering with electrospun polyvinylpyrolidone (PVP) nanofiber templates. The as-sputtered samples were annealed at different temperatures (500–1000 °C) in O2 ambient in order to remove their PVP cores and make the HfO2 shells well crystallized. Morphologies and crystal configuration of the samples were investigated by optical microscope, scanning electron microscopy, transmission electron microscopy, x–ray diffraction, and Raman spectroscopy. The nanotubes have uniform intact structure with an average diameter of 200 nm and a wall thickness of about 25 nm. Photoluminescence (PL) properties of the RE doped nanotubes have been studied in detail. The emission peaks of the aligned HfO2:Eu and HfO2:Tb nanotubes could correspond to the 5D0→7FJ (J=0–2) transitions of Eu3+ and the 5D4→7FJ (J=3–6) transitions of Tb3+, respectively. The PL intensities of the HfO2:RE3+ nanotubes were higher by several orders of magnitude than that of the films. This enhancement in the PL could be ascribed to the high density of surface states of HfO2:RE3+ nanotubes. [ABSTRACT FROM AUTHOR]

Green photoluminescence (PL) from polycrystalline [Zn.sub.3][N.sub.2] films doped with terbium (Tb), which are prepared on glass and Si substrates by direct current magnetron sputtering, is analyzed. The results have shown that Tb-doped [Zn.sub.3][N.sub.2] films are suitable for visible optoelectronic devices.

Terbium (Tb)-doped Zn3N2 thin films were prepared on glass and Si substrates by direct current magnetron sputtering in a mixture of pure argon and nitrogen gases. Glancing incidence x-ray diffraction patterns indicated that Zn3N2:Tb thin films were of cubic structure. Raman spectra showed only two Raman-active phonon modes located at 258 and 565 cm-1. The indirect optical band gap of Zn3N2:Tb was determined as 2.4 eV. The sharp characteristic emission lines corresponding to Tb3+ intra-4f shell transitions were resolved in the photoluminescence spectra at room temperature. Those results suggest that Tb-doped Zn3N2 may be a suitable material for visible optoelectronic devices. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Acute myeloid leukemia (AML) is a bone marrow malignancy. Long non-coding RNA (lncRNA) urothelial carcinoma- associated 1 (UCA1) plays an important role in several cancers. However, the role of lncRNA UCA1 in AML remained unclear. MATERIALS AND METHODS: LncRNA UCA1 expressions in different cell lines were determined by RT-PCR. In human myelogenous leukemia (ML) cell lines K562 and HL60, effects of lncRNA UCA1 knockdown on cell viability, migration, invasion, and apoptosis were assessed, respectively. Binding effects between lncRNA UCA1 and microRNA (miR)-126, and between miR-126 and RAC1 3'UTR were detected by RTPCR and luciferase activity assay. Involvements of miR-126 and RAC1 in lncRNA UCA1-mediated cell bioactivities were assessed. RESULTS: We found that lncRNA UCA1 was upregulated in ML cell lines. Knockdown of lncRNA UCA1 inhibited cell viability, migration, invasion, and prompted apoptosis of ML cells in vitro. LncRNA UCA1 could bind with miR- 126 and downregulate miR-126 expression. Simultaneously, the anti-growth and anti-metastasis actions of lncRNA UCA1 knockdown on ML cells were reversed by miR-126 suppression. RAC1 was a target gene of miR-126, and the anti-ML actions of miR-126 were abolished by RAC1 overexpression. Moreover, PI3K/AKT and JAK/STAT signaling pathways were blocked by miR-126 overexpression while were activated by RAC1 overexpression. CONCLUSIONS: Taken together, this study elucidates a novel UCA1-miR-126-RAC1 regulatory network in ML cells, which may provide the feasibility for use lncRNA-based therapy in AML treatment. [ABSTRACT FROM AUTHOR]

In view of the complexity and timeliness of train operation plan adjustment, a new algorithm of revolvingly calling ant colony algorithm is proposed in this paper. This new algorithm is proposed in consideration of train dispatching command process based on ant colony algorithm and is proposed based on the shortest path analysis of trains in emergency according to the idea that many shortest paths should be found for train operation path. With the (k-1) shortest path found, this algorithm can be used to search the K-th shortest path to solve or mitigate the problem of reasonable path allocation in adjustment of train operation plan and avoid the lack of passing capacity in local sections. [ABSTRACT FROM AUTHOR]

A rapid method for sensitive voltammetric determination of dinotefuran residue was reported. The proposed method was based on the electrocatalytic reduction of dinotefuran on β-cyclodextrin-graphene composite modified glassy carbon electrode (β-CD-rGO/GCE), giving rise to a higher reduction signal to dinotefuran relative to the bare (GCE) and graphene modified electrode (rGO/GCE). Moreover, a further signal enhancement was observed when the modified electrode incubated in solution at low temperature (0 °C) for a short time. The reduction mechanism and binding affinity were also discussed. The external standard calibration curve was obtained from linear sweep voltammetry in the range of 0.5 to 16.0 μM with a detection limit of 0.10 μM. In addition to optimization of pretreatment, this electrochemical method has been applied to the dinotefuran residue determination in millet samples with the detection limit of 0.01 mg kg−1 and compared with an high performance liquid chromatography method. The proposed electrode and analysis methods were proven to be sensitive, accurate and rapid under the used conditions. [ABSTRACT FROM AUTHOR]

The fruit set rate and yield of pear are commonly low due to insufficient pollination, as the species is unattractive to honeybees. To improve honeybee foraging behavior for the pollination of Dangshan pear (Pyrus bretschneideri cv. dangshansuli), nine methods were used to attract bees. A control treatment of colonies was fed with normal sugar syrup, while six other treatments were fed using sugar syrup mixed with Pear syrup, Gallic acid, Arginine (Arg), Lysine (Lys), Methionine (Met), or 8-Br-cGMP; plates containing Juvenile Hormone analog ZR-512, Brood Pheromone (BP), and Queen Mandibular Gland Pheromone (QMP) were placed inside the hives of another three treatments. Pollination efficacy was compared using the pollen load weight and quantity of foraging bees. The peak time of pear pollen gathering was 10:00-11:00 regardless of treatment. The pear pollen load weight per day was increased by all nine treatments. Pear pollen load weight per day was 49.11 g in the control. The QMP treatment yielded the heaviest pear pollen load weight per day (77.56 g), followed by the 8-Br-cGMP (64.45 g) and BP treatments (64.20 g). The percentages of pear pollen weight and quantity in the total pollen per day were both highest in the BP treatment (80.23%, 87.27%), followed by those in the QMP (79.32%, 86.74%) and Lys treatments (76.25%, 85.81%). In conclusion, BP was the most effective treatment for improving honeybee pollination behavior in the pear orchard, while other treatments, including Arg, Lys, 8-Br-cGMP, ZR-512, and QMP, could also be useful. [ABSTRACT FROM AUTHOR]

Lack of the evaluation method for timber structure has been developed as a critical problem in decades to protect the ancient timber building. Therefore, it is essential to conduct an intensive study on the failure mechanism of the ancient timber building in order to precisely predict the structural failure prior to earthquake and evaluate the seismic damage and structure maintenance after the earthquake. Based on the test of dovetail column-frame and bracket sets under low reversed cyclic loading and the shaking table test of overall structure, the "potential of destruction-resistance" of the two energy-consuming components under low reversed cyclic loading and the energy dissipated of each energy-consuming component under various earthquake conditions were investigated. A seismic damage evaluation model of the energy- consuming components/structure based on the "potential of failure-resistance" and the energy dissipation was developed. With the failure coefficient, the damage level of each energy-consuming component and the overall structure can be evaluated respectively. Finally, the seismic damage evaluation model is validated by the experiment result. [ABSTRACT FROM AUTHOR]