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A large qubit capacity and an individual readout capability are two crucial requirements for large-scale quantum computing and simulation1. As one of the leading physical platforms for quantum information processing, the ion trap has achieved a quantum simulation of tens of ions with site-resolved readout in a one-dimensional Paul trap2–4 and of hundreds of ions with global observables in a two-dimensional (2D) Penning trap5,6. However, integrating these two features into a single system is still very challenging. Here we report the stable trapping of 512 ions in a 2D Wigner crystal and the sideband cooling of their transverse motion. We demonstrate the quantum simulation of long-range quantum Ising models with tunable coupling strengths and patterns, with or without frustration, using 300 ions. Enabled by the site resolution in the single-shot measurement, we observe rich spatial correlation patterns in the quasi-adiabatically prepared ground states, which allows us to verify quantum simulation results by comparing the measured two-spin correlations with the calculated collective phonon modes and with classical simulated annealing. We further probe the quench dynamics of the Ising model in a transverse field to demonstrate quantum sampling tasks. Our work paves the way for simulating classically intractable quantum dynamics and for running noisy intermediate-scale quantum algorithms7,8 using 2D ion trap quantum simulators.In this work, stable trapping of a two-dimensional Wigner crystal of above 500 ions is achieved, and the quantum simulation of 300 ions with individual state detection demonstrated. [ABSTRACT FROM AUTHOR]

Effect of temperature on the corrosion behavior of CoCrNi medium-entropy alloy (MEA) in 3% NH4Cl solution was investigated by means of electrochemical measurements, immersion test and statistics analysis. The results show that increasing temperature makes it more difficult to form stable passive film on the MEA surface, accelerates the rupture of the film and reduces the anti-corrosion resistance of the MEA. Particularly at higher temperature, the corrosion rate of the MEA increases, as well the size and number of pits increase. In addition, NH4+ is further hydrolyzed with increasing solution temperature, which promotes the initiation and propagation of metastable pitting, slows down the re-passivation process and enhances the possibility of transition from metastable pitting to stable pitting. [ABSTRACT FROM AUTHOR]

The comparison of corrosion resistance between CoCrFeMnNi high entropy alloy (HEA) and 2205 duplex stainless steel (DSS) in a simulated concrete pore solution was investigated. The results reveal that compared with 2205 DSS, the passive film produced on CoCrFeMnNi HEA possesses a stronger protective ability with a thicker and more stable structure. The initiation frequency, lifetime and peak current value of metastable pitting of the HEA are lower than those of 2205 DSS, indicating that the metastable pitting corrosion is more difficult to occur in HEA. Moreover, the HEA suffers from scattered small-sized pitting, whereas dense and large pits are generated on 2205 DSS. Thus, the HEA exhibits a superior corrosion resistance in comparison with the DSS. [ABSTRACT FROM AUTHOR]

This article aims to research the corrosion behavior of CoCrNi medium-entropy alloy (MEA) in acidified coastal seawater environment. The results show that alternating current and HSO3− are destructive to the protective ability of passive film and weaken the anti-corrosion property of the MEA. AC causes damage to the passivation film by promoting HCO3− and HSO3− ionizing extra large amounts of H+, and enhancing the adsorption of corrosive ions (H+ and Cl−). Moreover, the synergistic effect of AC and HSO3− significantly facilitates the development of metastable pitting corrosion. As a result of AC imposition, the cathodic reaction transforms from the co-occurrence of hydrogen evolution and oxygen absorption to hydrogen evolution, which reveals that AC is a critical factor in destroying the corrosion resistance of the MEA. [ABSTRACT FROM AUTHOR]

A comparative study on the corrosion behavior of CoCrNi medium-entropy alloy (MEA) with CoCrFeMnNi high-entropy alloy (HEA) in SO2-polluted marine environment was investigated by a series of tests. Results indicate that CoCrNi MEA possesses smaller passive current density, larger polarization resistance and lower corrosion rate compared with those of CoCrFeMnNi HEA, which demonstrates that the MEA possesses better anti-corrosion performance than the HEA. This could be ascribed to the detail difference in the microstructure and passive film of the two alloys. Compared with the MEA, the smaller grain size and the larger number of oxides reduce the anti-corrosion performance of the HEA. Moreover, the oxide and matrix constitute the micro-galvanic corrosion cell, which promotes the generation of pits. [ABSTRACT FROM AUTHOR]

A fine-grained micro-duplex AlCoCrFeNi2.1 eutectic high entropy alloy exhibited high strain rate superplasticity with an elongation to failure of ~ 960 pct at 1173 K and a strain rate of 10-1 s-1. Optimum superplasticity was associated with a strain rate sensitivity of ~ 0.5, and there were transitions to non-superplastic flow with strain rate sensitivities of < 0.5 at both low and high strain rates. Superplasticity is attributed to grain boundary sliding with the observed retention of an equiaxed grain morphology, with some grain growth. Cavities with dimensions in the range of 1 to 5 μm were observed in specimens pulled to failure. Although analysis revealed that cavity nucleation is likely under the experimental conditions, cavity growth was slow because of control by a plasticity growth rate that was proportional to the cavity size. [ABSTRACT FROM AUTHOR]

The corrosion behavior of CoCrFeMnNi high entropy alloy in 3.5 wt.% NaCl solution with and without 0.05 M NaHSO3 was studied by electrochemical measurement, immersion test, and atomic force microscope. The results show that with the addition of HSO3−, the state of activation indicated by the anodic reaction evolves to the passivation state. Corrosion resistance is related to the state of the film on the HEA surface. The addition of HSO3− may produce a protective composition that transforms the corrosion product film into passive film. With the presence of HSO3−, the dense and highly protective passive film is formed, which improves the corrosion resistance of the HEA. Without HSO3−, the loose, incompact and incomplete corrosion product film produced on the surface of the HEA exhibits a low protective effect. [ABSTRACT FROM AUTHOR]

Aiming to solve the intrinsic brittleness of Sn–Bi solder alloy, the effects of In element on the microstructure evolution, mechanical and soldering properties were systematically investigated in Sn–57Bi–1Ag-based alloy. It was found that the addition of In could fragment the reticular Bi-rich phase and increase the content of β-Sn phase in the Sn–(57 − x)Bi–1Ag–xIn alloy, which significantly improved the fracture elongation of the In-containing solder alloy. The elongation of Sn–56.0Bi–1Ag–1.0In reached 68.51%, which was 2.3 times that of Sn–57Bi–1Ag (~ 29.68%). What’s more, the fracture mechanism of the alloy changes from brittle fracture to mixed ductile-brittle fracture with the addition of In element, implying a significant progress in solving the brittleness problem of Sn–Bi solder alloy. Meanwhile, compared to Sn–57Bi–1Ag, the lower melting point and solidification temperature of the In-containing solder alloys improved the solderability, which enhances the spreading rate of alloy and results in a maximum spreading rate of 72.00% for the Sn–56.0Bi–1Ag–1.0In. This work provides a valuable guidance for industrial production of solder alloys as it simultaneously improved both the solderability and the ductility of Sn–Bi-based alloys. [ABSTRACT FROM AUTHOR]

The corrosion behavior and mechanism of CoCrFeMnNi high-entropy alloy (HEA) in different concentrations of NH4Cl solution were studied by a series of tests. The results reveal that as NH4Cl concentration increases, the protection capability of surface passive film weakens, and the corrosion resistance of the HEA decreases. The corrosion form caused by the selective dissolution of Fe, Co and Ni element is evolved from pit to intergranular corrosion with increasing NH4Cl concentration. Additionally, under high-passive potential and high NH4Cl concentration, metastable pitting is more difficult to re-passive, which easily develops into stable pitting. [ABSTRACT FROM AUTHOR]

This article researches the influence of alternating current (AC) density on the corrosion behavior of CoCrNi medium-entropy alloy (MEA) in 3.5% NaCl solution by using electrochemical measurements, atomic force microscopy, and immersion test. The results show that the damaging effect of AC on the stability and protection of passive film may be due to the increasing adsorption effect of harmful ions (H+, Cl−). With the increase in iAC, the corrosion morphology evolves from pitting corrosion to general corrosion. Moreover, the applied AC facilitates the initiation and propagation of metastable pitting corrosion. The existence of cathodic oxide inclusion facilitates the occurrence of pits due to micro-galvanic corrosion. Metal elements are selectively dissolved in the matrix and oxide inclusion. [ABSTRACT FROM AUTHOR]

The effect of different AC current densities on the corrosion behavior and mechanism of CoCrNi MEA in carbonate/bicarbonate solution was evaluated by a series of corrosion test methods. The results reveal that the interference of AC damages the internal structure of the passive film, increases its defect amount, and reduces the stability and protection of the film. With the increase in iAC, the corrosion rate of the MEA apparently increases, and the corrosion form is evoluted from pitting corrosion to general corrosion. In particular, the more severe corrosion occurs at 150 A/m2, which is attributed to a large number of H atoms distributed on the surface of the MEA. In addition, the formation of pitting is mainly due to the selective dissolution of Co element, while Co and Ni elements in the oxide are selectively dissolved in the corrosion process. [ABSTRACT FROM AUTHOR]

The influence of microstructure and passive film on the corrosion behavior of CoCrFeMnNi high-entropy alloy (HEA) prepared by different cooling methods in alkaline soil simulation solution was investigated by electrochemical measurements, immersion test, atomic force microscopy, and x-ray photoelectron spectrometry. The results show that the corrosion resistance of the HEA decreases with decreasing cooling rate, and the water-cooled sample exhibits the best anti-corrosion property. The corrosion behavior of the HEA is closely related to σ-phase, grain size, oxide, and passive film. The micro galvanic corrosion effect between grain boundary (GB) and inner-grain reduces as the grain size increases. σ-phase distributed at GBs and the oxide increases the susceptibility to pitting corrosion. The increasing number of σ-phase significantly reduces the corrosion resistance of HEA. And pits around GB regions and σ-phase are attributed to the selective dissolution of Fe, Co, and Cr elements. The pits generated in the interior of σ-phase are mainly caused by the selective dissolution of Cr. The passive film of the water-cooled sample contains higher contents of Cr2O3, Fe2O3, and bound water, and lower contents of Mn oxide and FeO, which has better protection ability to the matrix. Moreover, a dense passive film is formed on the water-cooled sample as indicated by the fact that the donor density (ND) of passive film on the furnace-cooled sample is approximately 1.65 times that of water-cooled sample. [ABSTRACT FROM AUTHOR]

This paper examined the effect of Si addition on the cracking resistance of Inconel 939 alloy after laser additive manufacturing (AM) process. With the help of CALculation of PHAse Diagrams (CALPHAD) software Thermo-Calc, the amounts of specific elements (C, B, and Zr) in liquid phase during solidification, cracking susceptibility coefficients (CSC) and cracking criterion based on d T / d f s 1 / 2 values (T: solidification temperature, fs: mass fraction of solid during solidification) were evaluated as the indicators for composition optimization. It was found that CSC together with d T / d f s 1 / 2 values provided a better prediction for cracking resistance. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the corrosion behavior of CoCrFeMnNi high-entropy alloy (HEA) at various AC current densities and solution temperatures in a simulated concrete pore solution by using electrochemical measurements, immersion test and surface analysis technology. The results show that with increasing AC current density (iAC) and solution temperature, the passivation of the HEA decreases, which impedes the formation of passive film, impairs film stability, increases the possibility of the film rupture, and exacerbates the degree of pitting corrosion. In particular, under the combined action of high iAC and solution temperature, the passivation of the HEA becomes extremely difficult and the corrosion rate is dramatically enhanced, which reflects that increasing iAC and solution temperature produce a synergistic effect, remarkably reduces the protective property of passive film and aggravates the corrosion. Pits form on the HEA surface due to the selective dissolution of Fe, Co and Ni elements. [ABSTRACT FROM AUTHOR]

The rotating magnetocaloric effect has been researched in double perovskite Tb 2 CoMnO 6 by Monte Carlo simulation. The magnetization, specific heat and isothermal entropy change are presented for magnetic fields in different directions ( h ‖ c and h ⊥ c ). The rotating magnetic entropy, transition temperature and relative cooling power are given as well. Due to the different magnetic anisotropy, the spin of Co 2 + /Mn 4 + is parallel to c axis and the spin of Tb 3 + is perpendicular to c axis. The corresponding A-type antiferromagnetic order appears at T C = 94 K, and at T N = 15 K, ferromagnetic state appears. Different orientations of spins result in a big negative and positive rotating magnetic entropy appeared in different temperature. Those findings may provide a wider temperature range for magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

In order to directly detect the concentration of glucose in milk, carbon dots (CDs) rich in phenolic hydroxyl groups were synthesized in one step as a fluorescent probe. We presented a new glucose oxidase (GOx)-mediated strategy to detect glucose, which allowed the quantitative analysis of hydrogen peroxide (H2O2) and glucose. Furthermore, it was possible to detect H2O2 and glucose directly in complex systems such as milk. The result in milk showed that the fluorescence of the CDs was quenched by H2O2 with the concentration range from 1 to 100 μM linearly, and the correlation coefficient was 0.977 with a detection limit of 0.175 μM. Similarly, a linear correlation was built between the fluorescence of the CDs and the concentration of glucose in the range from 10 to 100 μM with a correlation coefficient of 0.968 and a detection limit of 0.686 μM. The recovery rate was 97.30–101.05%, which showed high sensitivity in the detection of glucose in milk. As far as we know, this was the first time that CDs were used as a fluorescent probe to detect glucose in milk directly, which removed the step of pretreating milk and provided a supplement and extension for the detection of glucose in fluorescent spectroscopy. [ABSTRACT FROM AUTHOR]

Purpose: Lysophosphatidic acid (LPA) is a bioactive molecule which participates in many physical and pathological processes. Although LPA receptor 6 (LPAR6), the last identified LPA receptor, has been reported to have diverse effects in multiple cancers, including breast cancer, its effects and functioning mechanisms are not fully known. Methods: Multiple public databases were used to investigate the mRNA expression of LPAR6, its prognostic value, and potential mechanisms in breast cancer. Western blotting was performed to validate the differential expression of LPAR6 in breast cancer tissues and their adjacent tissues. Furthermore, in vitro experiments were used to explore the effects of LPAR6 on breast cancer. Additionally, TargetScan and miRWalk were used to identify potential upstream regulating miRNAs and validated the relationship between miR-27a-3p and LPAR6 via real-time polymerase chain reaction and an in vitro rescue assay. Results: LPAR6 was significantly downregulated in breast cancer at transcriptional and translational levels. Decreased LPAR6 expression in breast cancer is significantly correlated with poor overall survival, disease-free survival, and distal metastasis-free survival, particularly for hormone receptor-positive patients, regardless of lymph node metastatic status. In vitro gain and loss-of-function assays indicated that LPAR6 attenuated breast cancer cell proliferation. The analyses of TCGA and METABRIC datasets revealed that LPAR6 may regulate the cell cycle signal pathway. Furthermore, the expression of LPAR6 could be positively regulated by miR-27a-3p. The knockdown of miR-27a-3p increased cell proliferation, and ectopic expression of LPAR6 could partly rescue this phenotype. Conclusion: LPAR6 acts as a tumor suppressor in breast cancer and is positively regulated by miR-27a-3p. [ABSTRACT FROM AUTHOR]

Objectives: Inconsistent results exist on the role of tea consumption on subsequent risk of fracture. A dose-response metaanalysis was therefore conducted to assess the association of tea consumption with the risk of fracture based on prospective cohort studies. Methods: The electronic databases of PubMed, Embase, and the Cochrane library were systematically searched to identify prospective cohort studies from inception until September 2020. The categories of high versus low and dose-response meta-analyses for tea consumption on the risk of fracture were calculated using the random-effects model. Eight prospective cohort studies recruited 774,134 individuals selected for the final meta-analysis. Results: An increment of 1 cup in tea consumption was not associated with the risk of fracture [relative risk (RR), 0.98; 95% confidence interval (CI), 0.96-1.00; P = 0.102]. Moreover, the highest tea consumption category was associated with a reduced risk of fracture (RR, 0.93; 95% CI, 0.88-0.98; P = 0.005). Furthermore, heavy (RR, 0.91; 95% CI, 0.85-0.98; P = 0.008) and mild (RR, 0.97; 95% CI, 0.94-1.00; P = 0.046) tea consumption were associated with lower risk of fracture. However, moderate tea consumption was not associated with the risk of fracture (RR, 0.98; 95% CI, 0.94-1.02; P = 0.281). Conclusion: This study found that increased tea consumption may provide a protective role in the risk of fracture. The benefits of tea consumption should be further explored according to the characteristics of the individuals. [ABSTRACT FROM AUTHOR]

The effect of aging time on corrosion behavior of 2507 super duplex stainless steel (SDSS) under a 3.5wt.% NaCl solution was explored by electrochemical tests, atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), and immersion test. The experimental results indicate that with an increasing aging time, the anti-corrosion property of 2507 SDSS aged at 850 °C decreases significantly. The SDSS aged for 5 min contains two precipitated phases (χ, γ2). As aging time increases, the quantity of σ phase precipitates significantly increases, which seriously reduces the corrosion resistance of SDSS due to the increasing number of micro-galvanic corrosion cells. In addition, the passive film of SDSS aged for 60 min exhibits the minimum values of Rct and Rf, as well as the maximum carrier densities. For the aging time of 5 min, the passive film consists of higher contents of Cr2O3 and H2O, as well as less FeO, while also demonstrating good stability and compactness. The precipitated phases seriously decrease the protective ability of passive film, especially the σ phase. [ABSTRACT FROM AUTHOR]

Purpose: Clinically, hypoxia is associated with increased distant metastasis and poor survival in gastric cancer (GC). In this study, we set out from the cellular interaction to further explain the molecular mechanism of invasion in GC cells under hypoxic conditions. Methods: Gastric cancer cells were cultured under 1% O2 (hypoxia-cultured gastric cancer cells, HGC) and 20% O2 condition (normoxic-cultured gastric cancer cells, NGC). NGC was co-cultured with HGC-medium. Scrape and Transwell were used to evaluate invasion and migration. Exosomes from GC were extracted by ultracentrifugation. Electron microscopy images, western-blot used to analyze the size distributions and the number of exosomes. Results: HGC-medium induced NGC dissociated. Long non-coding RNA (lncRNA) prostate cancer gene expression marker 1 (PCGEM1) was specifically expressed in HGC exosomes. HGC-derived PCGEM1-riched exosomes could promote the invasion and migration of NGC. On the mechanism, PCGEM1 maintained stability and reduced the degradation of SNAI1, which could induce the epithelial–mesenchymal transition of GC. Conclusion: LncRNA PCGEM1 was overexpressed in GC cells. And part of the PCGEM1 can be encapsulated into exosomes. These exosomes promoted invasion and migration of other GC cells. We considered PCGEM1 might act as a "scaffold" combined with SNAI1 and prompt the invasion and migration of GC. [ABSTRACT FROM AUTHOR]

Effect of passive potential on the protective capacity of passive film formed on CoCrFeMnNi high-entropy alloy was investigated in carbonate/bicarbonate solution by using electrochemical measurements, atomic force microscopy and x-ray photoelectron spectroscopy (XPS). The results reveal that the protective ability of passive film is sensitive to the applied potential, and the anti-corrosion property of passive film at high potential is significantly enhanced as indicated by the high film resistance and the low donor densities. The Cr2O3 content and the ratios of Mn/Mnox as well as O2−/OH− in the secondary passive film are greater than those in the primary passive film. Moreover, increasing the potential facilitates the formation of a homogeneous and thick passive film, which considerably improves the protective ability of the film. [ABSTRACT FROM AUTHOR]

Two mononuclear Cu(II) and Co(II) halogen-substituted salamo-based complexes of the formulas [Cu(L)] and [Co(L)(H2O)2] have been synthesized and characterized by elemental analyses, FT-IR and UV-Vis absorption spectra, and X-ray crystallography. The Cu(II) complex has crystallized in the monoclinic system, space group P21/n with Cu(II) atom located in the N2O2 cavity. In the Co(II) complex, the center Co(II) atom has exhibited a slightly distorted octahedral geometry with halogen-substituted salamo-based bisoxime forming the basal N2O2 coordination plane and two oxygen atoms of two coordinated water molecules in the axial positions. Non-covalent interactions like hydrogen bonding and π···π stacking interactions are operative in construction of supramolecular architectures. The crystal structures and supramolecular features of the complexes have been discussed in details. Hirshfeld surfaces analyses has indicated stability of both complexes. The Cu(II) complex has demonstrated excellent bio-inspired catalytic properties towards oxidative coupling of 2-AP in MeCN medium. Fluorescence properties of H2L and its Cu(II) and Co(II) complexes have also been discussed. [ABSTRACT FROM AUTHOR]

The effects of Cl− concentration and applied alternating current (AC) on the corrosion behavior of 2507 super duplex stainless steel (SDSS) were studied in a saturated Ca(OH)2 solution by electrochemical measurements, immersion test, and x-ray photoelectron spectroscopy. The results show that the presence of Cl− ions accelerates the corrosion of 2507 SDSS in the saturated Ca(OH)2 solution. The protective ability of passive film decreases as Cl− concentration increases, especially at the concentration of 10% Cl−. As the applied iAC increases, the ip value increases, and the Ep value decreases. The applied AC increases the number of defects within the passive film, affects the electronic property of the surface film, which results in a harmful effect on the passive film, and weakens its anti-corrosion property. The higher the iAC, the more severe the damage influence is. Moreover, imposed AC promotes the pitting corrosion sensitivity of SDSS and enhances its corrosion rate. The applied AC and the addition of Cl− exert a combined effect, reducing the corrosion resistance of passive film formed on 2507 SDSS. [ABSTRACT FROM AUTHOR]

The influence of solution temperature on the corrosion behavior of 6061-T6 aluminum alloy in 3.5% NaCl solution was studied by electrochemical tests, weight loss method, and surface morphology analysis. The results show that the samples treated at different solution temperatures have different corrosion resistance. The anticorrosion resistance of aluminum alloys decreases first and then increases as the solution temperature increases. At 535 °C, the sample has the optimal corrosion resistance, with a slight corrosion degree, while the alloy sample treated at 555 °C shows the most severe degree of corrosion, with a large number of different sized pits and some ulcerous corrosion pits, as well the apparent intergranular corrosion. The corrosion behavior of different solid aluminum alloy samples is closely related to the microstructure. The Mg2Si precipitates act as the anode phase to protect the substrate, and a decrease in the amount of AlFeSi precipitates reduces the number of micro-galvanic corrosion cells, and the severe segregation of AlFeSi precipitates accelerates the corrosion. [ABSTRACT FROM AUTHOR]

Homology-directed (HD) genome modification offers an opportunity to precisely modify the genome. Despite reported successful cases, for many loci, precise genome editing remains challenging and inefficient in vivo. Here we report an effort to precisely knock-in a GFP reporter into gad locus mediated by CRISPR/Cas9 system in the zebrafish Danio rerio. PCR artifact was detected in testing for homologous recombination (HR), but was mitigated by optimizing PCR condition and decreasing the injected targeting plasmid concentration. Under this optimized condition, time course analysis revealed a decline of the HR-positive embryos at embryogenesis progressed. GFP signals also diminished at later developmental stages. The GFP signals were consistent with PCR detection, both of which suggested the loss of targeted insertion events at later stages. Such loss of insertion might be one underlying reason for the inability to obtain germ-line transgenic lines with GFP knocked into the gad locus. Our results suggest that the low HR efficiency associated with CRISPR-mediated knock-in is in part due to loss of insertion after targeted integration into the gad locus. [ABSTRACT FROM AUTHOR]

This study compares the difference between primary and secondary passive films formed on 2507 super duplex stainless steel (SDSS) in simulated concrete pore solution by means of electrochemical analysis and x-ray photoelectron spectroscopy (XPS) combined with atomic force microscopy (AFM). The results reveal that the primary film possesses superior corrosion resistance as indicated by the lower passive current density, higher polarization resistance, and smaller amounts of defects within the passive film. The structure characterized by particles with different heights and diameters in the secondary passive film facilitates the film degradation. Moreover, at 0.48VSCE, the CrO3 is formed in the secondary passive film, and the Fe species is more prone to transform to FeOOH and Fe2O3. [ABSTRACT FROM AUTHOR]

An investigation into Type II solar radio bursts was carried out to understand the frequency gap between fundamental and harmonic emissions of the radio burst. This investigation focused on Type II solar radio bursts with flares and coronal mass ejections by relating the separation between fundamental and harmonic emissions. We used the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Spectrometers (CALLISTO) and a newly designed low-frequency antenna array. This article describes the proposed new instrument in terms of its antenna design, the bandpass testing of the antenna, the new system significance in studying Type II solar radio bursts, and its comparison with other leading radio solar monitoring instruments. Upon setting up the new technology, the radio-frequency interference of the observation site at the University of Malaya was shown to emphasize the suitability of the selected site. This article also shows the preliminary results of the proposed new instrument by reporting the detection of a Type III solar radio burst that was confirmed by CALLISTO. Moreover, it also includes the optimal observation design and strategies for future detections. [ABSTRACT FROM AUTHOR]

The effect of solution annealing temperature on microstructure and the corresponding AC (alternating current) corrosion behavior was investigated by electrochemical impedance spectroscopy, polarization curve, Mott–Schottky curve and immersion test. With or without AC application, the 2507 SDSS (super-duplex stainless steel) samples annealed at various temperatures exhibit a difference in corrosion resistance. Among them, the corrosion resistance first increases and then decreases as the annealing temperature increases, that is, the 2507 SDSS annealed at 1060 °C has the optimum corrosion resistance, followed by the specimen annealed at 1000 °C, and finally the specimen at 1120 °C. The variation trends of Rct, Rf and ip can verify the above law. The σ phase and an excessive amount of α phase within the microstructure can decrease the corrosion resistance. Additionally, the stability and protective property of passive film formed on the electrode surface is associated with the microstructure of 2507 SDSS. An imposed AC can decrease the passivity of 2507 SDSS and damage the film formed on the sample surface. Furthermore, the corrosion rate and pitting sensitivity of the SDSS increase with the increasing AC current density. [ABSTRACT FROM AUTHOR]

The relationship between microstructure and alternating current (AC) corrosion behavior of X80 pipeline steel was systematically studied in CO32−/HCO3− solution using corrosion tests and surface analysis technology. The results show that AC prevents the formation of passive film and decreases its stability. AC generates a different damage effect to the passive film on steels with various microstructures. The passive film of normalized microstructure steel has a relatively high stability, followed by the hot-rolled steel, and that of the annealed sample is the most unstable. The influence of AC on passive film of steels with various microstructures causes a difference in the corrosion resistance. The corrosion form of steels with different microstructures applied with AC displays the obvious characteristic of localized corrosion. The normalized microstructure has the optimum corrosion resistance, followed by the hot-rolled steel, and the annealed steel possesses the worst corrosion resistance. The difference in the AC corrosion behavior of X80 steels may be related to the microstructure. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to explore the differences between stage T2N0M0 and stage T1N1M0 gastric cancer (GC) and to identify the necessity of adjuvant treatment (AT) for these stages. Methods: Between years 2004 and 2015, 1971 stage IB GC patients who underwent radical surgery were recruited using the Surveillance, Epidemiology and End Results database. We conducted univariate/multivariate analyses, the propensity score matching and evaluated gastric cancer-specific survival (GCSS) and overall survival (OS) with the log-rank test. Results: T1N1M0 had a significantly worse survival than T2N0M0 in both GCSS and OS before and after the propensity score matching. Examined lymph nodes (ELN) ≤ 15 and T1N1M0 were independent risk factors for worse GCSS and OS in stage IB GC. The absence of adjuvant chemotherapy (CT) was an independent risk factor for worse GCSS and OS in T1N1M0 but not in T2N0M0. AT demonstrated similar GCSS and OS with surgery alone (SA) for T2N0M0 but better survival for T1N1M0. Compared to CT and adjuvant chemoradiotherapy (CRT) group, SA demonstrated significantly worse GCSS and OS for T1N1M0. There was no significant difference between CT and CRT in both T2N0M0 and T1N1M0 stages. T2N0M0 had a better survival than T1N1M0 in ELN ≤ 15 subgroup. However, similar survival was demonstrated in ELN > 15 subgroup. Conclusions: T2N0M0 GC has a better survival rate than T1N1M0 GC when ELN are ≤ 15. Moreover, T2N0M0 GC may not benefit from AT. T1N1M0 GC requires CT but not adjuvant radiotherapy. [ABSTRACT FROM AUTHOR]

The alternating current (AC) corrosion behavior of X80 steels annealed for different times was investigated in an alkaline soil simulation solution by electrochemical measurement, immersion test and surface analysis technology. The results show that with or without AC interference, the steels annealed for various times have different corrosion resistance. The anticorrosion resistance of steel improves with an increase in annealing time. AC interference results in the evolution of the main cathodic reaction, and facilitates the corrosion of the steels. The steel annealed for 20 min presents a more severe corrosion degree with distinct pits. The corrosion behavior of the steels annealed for different times with AC application is closely related to the microstructure. A decrease in pearlite reduces the number of galvanic corrosion cells, decreasing the corrosion rate of steel. And the grain increase is beneficial for improving the corrosion resistance of the annealed steel. [ABSTRACT FROM AUTHOR]

Purpose: Hypoxia is an indispensable factor in the progression of metastasis. Hypoxia inducible factor-1α (HIF-1α), the core element in generating the hypoxia response, induces invasion and metastasis by promoting epithelial–mesenchymal transition (EMT). This study explored the underlying mechanism of hypoxia associated with the invasion and metastasis of gastric cancer (GC). Methods: Six methods were employed to assess the function of the long noncoding RNA (lncRNA) prostate cancer gene expression marker 1 (PCGEM1) including gene silencing, RT-PCR, the separation of nuclear and cytoplasmic fractions, scrape motility assay, transwell migration assay, and Western-blot. Results: LncRNA PCGEM1 was overexpressed in GC cells and tissues, and was induced by hypoxia in GC cells. Additional experiments confirmed that the knockdown of PCGEM1 significantly repressed the invasion and metastasis of GC cells. SNAI1, a key transcription factor of EMT, was regulated by PCGEM1. Overexpression of SNAI1 rescued the inhibition of PCGEM1-knockdown during the invasion and metastasis of GC cells. In addition, PCGEM1 and SNAI1 jointly affected the biomarkers of EMT. Conclusion: Our findings indicated that PCGEM1 is a hypoxia-responsive lncRNA, and contributes to the invasion and metastasis of GC. The potential mechanism is attributed to the regulation of EMT by PCGEM1 and its influence on the expression of SNAI1. [ABSTRACT FROM AUTHOR]

Corrosion behavior of X65 pipeline steels with different microstructures under alternating current (AC) interference was investigated in acid soil simulation solution by potentiodynamic polarization curve, potentiostatic polarization curve and immersion test. The results show that superimposed AC causes a sharp increase in corrosion current density of X65 steel. With the increase in iAC, the corrosion current densities of steels with various microstructures increase, especially at high iAC. Hot-rolled steel mainly experiences uniform corrosion, with very slight pit corrosion. Serious corrosion degrees with intensive corrosion pits can be observed on the surfaces of normalized and quenched microstructure steels. The annealed steel exhibits the feature of non-uniform corrosion with some pitting. The steels with various microstructures applied with AC have different corrosion resistance. The normalized steel shows the worst corrosion resistance, then the quenched microstructure, and the hot-rolled steel displays the optimum corrosion resistance. The difference in the microstructure can result in difference in corrosion degree and occurrence position of pitting corrosion of X65 steel. The normalized microstructure composed of polygonal ferrite and a large amount of pearlite and bainite is the most susceptible to AC corrosion. [ABSTRACT FROM AUTHOR]

In this study, the geometry of open-cell foams is simulated using a model based on Voronoi tessellations. The fracture toughness of open-cell foams with Voronoi cells, including Mode-I, Mode-II, and the mixed-mode ones, are calculated by the finite-element method based on a micromechanical model. Cracks in the micromechanical model are created through removing some number of cells pertaining to the crack length. Displacement boundary conditions are applied to the boundary of a small region surrounding the crack tip, which are calculated based on the linear elastic fracture mechanics. The effects of relative density, disorder factor and sample size on the predicted elastic properties and fracture toughness of open-cell foams with Voronoi cells are discussed and compared with results available in the literature. [ABSTRACT FROM AUTHOR]

It has been known that the internal structure of metallic glass is composed of elastic region and fragile region. However, it is not clear whether the distribution of these regions has an effect on the occurrence of crystallization behavior. Here, the molecular dynamics simulation is employed to investigate the nanometer scale crystallization behavior in metallic glass. A regional selective characteristic is revealed for the occurrence of crystallization behavior in the metallic glasses, which is different from that in the melt, showing the unique nature of crystallization behavior in amorphous system. It is observed that the crystallization behavior occurs first in the elastic region dominated by the icosahedral network, rather than in the fragile region dominated by the low-population polyhedron. This phenomenon can be attributed to that the Gibbs free energy barrier between the BCC structure and the low-population polyhedron in the fragile region is higher than the free energy barrier between the BCC structure and the icosahedral network. [ABSTRACT FROM AUTHOR]

To better understand the corrosion behaviors of CoCrFeNi-based high-entropy alloys (HEAs), the CALculation of PHAse Diagrams (CALPHAD) method was used to simulate the Pourbaix diagrams for CoCrFeNi, CoCrFeNiCu and CoCrFeNiAl HEAs. Although the CALPHAD simulations were performed under equilibrium conditions, assisted by published experimental results on CoCrFeNi, CoCrFeNiCu and CoCrFeNiAl0.5 HEAs, the CALPHAD simulations provide insights into the corrosion behaviors, such as the oxidation layer pitting and forming potential, of the CoCrFeNi-based HEAs. [ABSTRACT FROM AUTHOR]

Objectives: This study was to evaluate the feasibility of simultaneous integrated boost on tumor hypoxia area by studying the dosimetric change of hypoxia imaging guidance on intensity-modulated radiation therapy for non-small cell lung cancer (NSCLC).Methods: Five NSCLC patients with large hypoxic volume participated in this study. FDG PET/CT images were fused with CT localization images to delineate gross tumor volume. FMISO PET/CT images were fused with CT localization images to delineate hypoxic biological target volume (BTV) (tissue maximum ratio ≥ 1.3) by threshold. BTV was irradiated with 72, 78 and 84 Gy, respectively, 30 times. The dosimetry differences were compared in target volume and organ at risk between simultaneous integrated boost plans and conventional radiotherapy plans.Results: Dosages on BTV of NSCLC hypoxic area were increased to 72, 78 and 84 Gy, respectively, by simultaneous integrated boost intensity-modulated radiation therapy. There was no obvious difference in dosage distributions on original target volume compared with those in conventional radiotherapy. Dosages on main organ at risk in chest met the dosimetric constraint, and there was no significant difference compared with those in conventional radiotherapy.Conclusion: It is feasible in dosiology that the dosages in NSCLC hypoxic area were added to 72, 78 and 84 Gy by simultaneous integrated boost with the guidance of 18F-FMISO PET/CT. [ABSTRACT FROM AUTHOR]

Laser surface strengthening was performed for AZ31B magnesium alloy specimens, with a rapid cooling in liquid nitrogen. Surface strengthening behavior and mechanism were investigated. The observed grain refinement, super solid solution, dislocation behavior and the amorphous structure formation resulted in a significant improvement of microhardness, wear resistance, and fracture toughness of magnesium alloy under study. It is shown that rapid laser heating and cooling in liquid nitrogen enhanced the grain refinement and formation of amorphous structure in the strengthening layer, were the number of dislocations exceeded that in the substrate. Furthermore, the distortion of lattice caused by large amounts of Al element dissolved in α-Mg phase also increased the resistance to dislocation motion. [ABSTRACT FROM AUTHOR]

For the development of non-polar nitrides based optoelectronic devices, high-quality films with smooth surfaces, free of defects or clusters, are critical. In this work, the mechanisms governing the topography and single phase epitaxy of non-polar m-plane gallium nitride ( m-GaN) thin films are studied. The samples were grown using plasma-assisted molecular beam epitaxy on m-plane sapphire substrates. Growth of pure m-GaN thin films, concomitant with smooth surfaces is possible at low radio frequency powers and high growth temperatures as judged by the high resolution x-ray diffraction, field emission scanning electron microscopy, and atomic force microscopy measurements. Defect types and densities are quantified using transmission electron microscopy, while Raman spectroscopy was used to analyze the in-plane stress in the thin films which matches the lattice mismatch analysis. Energy dispersive spectroscopy and cathodoluminescence support a congruent growth and a dominant near band edge emission. From the analysis, a narrow growth window is discovered wherein epitaxial growth of pure m-plane GaN samples free of secondary phases with narrow rocking curves and considerable smooth surfaces are successfully demonstrated. [ABSTRACT FROM AUTHOR]

Effects of heat treatment on borides precipitation and mechanical properties of arc-melted and laser-cladded CoCrNiFeAlCuBSi high-entropy alloys were comparatively studied. The arc-melted alloy contains lots of long strip borides distributed in the body-centered cubic phase, with a hardness about 643 HV. Laser-cladding can effectively inhibit the boride precipitation and the laser-cladded alloy is mainly composed of a simple bcc solid solution, with a high hardness about 769 HV, indicating the strengthening effect by interstitial boron atoms is greater than the strengthening by borides precipitation. Heat treatments between 800°C and 1200°C can simultaneously improve the hardness and fracture toughness of arc-melted alloys, owing to the boride spheroidization, dissolution, re-precipitation, and hence the increased boron solubility and nano-precipitation in the bcc solid solution. By contrast, the hardness of laser-cladded alloys reduce after heat treatments in the same temperature range, due to the decreased boron solubility in the matrix. [ABSTRACT FROM AUTHOR]

A series of multi-principal-element (MPE) alloys have been prepared by adding Ni, Mn, Al, Cu and Y into the reference CoCrFe-B alloy. The microstructure and mechanical properties of these MPE alloys have been investigated thoroughly. It is found that the addition of the elements can inhibit boride precipitation in the designed alloys and the solid solution strengthening effect induced by interstitial boron atoms is more significant than that by boride precipitation. The MPE alloys with the fcc phase as the main solid solution phase have a higher boron solubility and hence less boride precipitation, than those with the bcc phase as the main solid solution phase. The addition of yttrium can improve the boron solubility, decrease boride precipitation, control the boride morphology and, importantly, simultaneously improve the compressive strength and ductility of boron-containing MPE alloys. [ABSTRACT FROM AUTHOR]

It is challenging to measure accurately and with high spatial resolution the local thermal strains in heterogeneous microstructures due of the complex nature of the thermal deformations and local boundary conditions. In the enclosed study, a digital image correlation (DIC) based, thermal strain mapping technique is described that is able to probe thermal deformations with sub-micron spatial resolution and sub-nanometer displacement accuracy for both homogeneous and heterogeneous materials, including cross-sections of IC packages. The full-field thermal deformation maps of different materials within a nanostructured IC chip cross-section are established from room temperature up to 160 °C, uncovering the heterogeneous nature of the specimen while accurately measuring the highly non-uniform displacement and strain fields across the multiple material constituents. As described in this work, the DIC-enabled technique is capable of high resolution mapping of local thermo-mechanical deformations in heterogeneous materials, providing a methodology that can improve our understanding of complex material systems under controlled thermal-environmental conditions. [ABSTRACT FROM AUTHOR]

Summary: The present study aimed to identify the factors associated with osteoporosis in patients with chronic obstructive pulmonary disease in Taiwan. The study found that female sex, old age, and use of a high dose of oral corticosteroids were significantly associated with osteoporosis in these patients. Introduction: Chronic obstructive pulmonary disease (COPD) is becoming an increasingly serious and prevalent issue worldwide. The treatment of COPD with long-term steroid use may cause osteoporosis and have significant influences on disability and mortality. However, few studies have evaluated the association between steroid use and osteoporosis in patients with COPD. The present study aimed to identify the factors, including demographic characteristics and steroid use (oral corticosteroids [OCSs], inhaled corticosteroids, and injected steroids), associated with osteoporosis in patients with COPD in Taiwan. Methods: This was a retrospective case-control study. Data were obtained from the National Health Insurance Research Database from 1997 to 2009. Cox proportional hazard regression models were used to identify the factors associated with osteoporosis. Results: The incidence of osteoporosis in the patients with COPD was 1343.0 per 100,000 person-years, the majority of patients were women (63.6 %), and the mean age of the patients was 72.5 years. In multivariate regression analysis, female sex, old age, and use of a high OCS dose with a defined daily dose (DDD) >56 (hazard ratio 1.85, 95 % confidence interval 1.52-2.26, P < .0001) exhibited significant independent associations with osteoporosis. Conclusions: Female sex, old age, and use of a high OCS dose with a cumulative DDD >56 are associated with osteoporosis in patients with COPD. Additionally, female patients >50 years old and male patients >70 years old have a higher risk of osteoporosis. Medical personnel should actively provide health education for the prevention of osteoporosis in these patients. [ABSTRACT FROM AUTHOR]

A series of aliphatic diamine bridged hindered phenols was synthesized. Their antioxidant activity was evaluated for assessing the role of bridging groups in trapping 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) and in 2,2'-azodi(isobutyronitrile) (AIBN) induced oxidation of styrene. The study of reaction kinetics of scavenging of the peroxyl radicals demonstrated that the scavenging ability of the DPPH free radical decreased when length of the bridging groups increased. However, the ability to protect styrene from AIBN-induced oxidation increased with increased length of the bridging groups. [ABSTRACT FROM AUTHOR]

The high-concentration precursor solution of BiLaFeO (BLFO) was fabricated and stored under the different temperatures (40, 20, 0 °C). After 10 days, the solution at the temperature of 40 °C generated both bismuth acetate precipitation and nitrogen dioxide gas and at the temperature of 20 °C generated nitrogen dioxide gas, while the solution still maintains stability and transparency at the temperature of 0 °C. These results show that low temperature is an important way to improve the stability of high-concentration precursor solution in sol-gel method. Furthermore, the stability precursor solution is adopted to prepare BLFO thick film on indium tin oxide/glass substrate by spin coating combined with sequential layer annealing. The film exhibits a perovskite structure without impurity phase; especially, a comparatively high remanent polarization ( P ) of 42.85 μC/cm can be obtained, which may be related to lanthanum doping, preferred (110) orientation and relatively compact microstructure. Graphical Abstract: XRD patterns and cross-sectional structure of BiLaFeO thick film, polarization-electric field ( P- E) loops at various voltages. [ABSTRACT FROM AUTHOR]

The effects of foliar spraying with spermidine (Spd) on antioxidant system in tomato ( Lycopersicon esculentum Mill.) seedlings were investigated under high temperature stress. The high temperature stress significantly inhibited plant growth and reduced chlorophyll (Chl) content. Application of exogenous 1 mM Spd alleviated the inhibition of growth induced by the high temperature stress. Malondialdehyde (MDA), hydrogen peroxide (HO) content and superoxide anion (O) generation rate were significantly increased by the high temperature stress, but Spd significantly reduced the accumulation of reactive oxygen species (ROS) and MDA content under the stress. The high temperature stress significantly decreased glutathione (GSH) content and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), but increased contents of dehydroascorbic acid (DHA), ascorbic acid (AsA), and oxidized glutathione (GSSG) in tomato leaves. However, Spd significantly increased the activities of antioxidant enzymes, levels of antioxidants and endogenous polyamines in tomato leaves under the high temperature stress. In addition, to varying degrees, Spd regulated expression of MnSOD, POD, APX2, APX6, GR, MDHAR, DHAR1, and DHAR2 genes in tomato leaves exposed to the high temperature stress. These results suggest that Spd could change endogenous polyamine levels and alleviate the damage by oxidative stress enhancing the non-enzymatic and enzymatic antioxidant system and the related gene expression. [ABSTRACT FROM AUTHOR]

An Al–10.83Zn–3.39Mg–1.22Cu–0.16Zr–0.16Sc alloy was produced using the spray deposition technology. The microstructure evolution within temperature ranging between 613 K and 733 K during hot pressing process at different initial strain rate was investigated in a transmission electron microscope (TEM). Partial resolution of the primary precipitates in the deposited microstructure, such as η-MgZn2 and Al3(ScZr), took place. Moreover, new secondary η-MgZn2 and Al3(ScZr) precipitated from the super saturated solid solution and their effects on the recrystallization were also analyzed. The Al3(ScZr) and η-MgZn2 precipitation can act as barriers for the movement of both dislocations and grain boundaries, which are the main factors for hindering the recrystallization. Additionally, the dislocation slide during hot deformation was also investigated in detail. The spray deposition Al–Zn–Mg–Cu alloy own the well deformability, and the typical perfect dislocations can be found in the hot deformation Al–Zn–Mg–Cu alloy. [ABSTRACT FROM PUBLISHER]

Nonlinear random vibration of the cables with small sag-to-span ratio and excited by in-plane transverse uniformly distributed Gaussian white noise is studied by a nonlinear multi-degree-of-freedom system which is formulated with Galerkin's method. The stationary probabilistic solutions of the nonlinear system are analyzed with the state-space-split method in conjunction with the exponential polynomial closure method. Effectiveness of this approach about the cable random vibration is examined through comparison with Monte Carlo simulation and equivalent linearization method. The probabilistic solutions of the cable random vibrations are also studied by modeling the cable as single-degree-of-freedom system and multi-degree-of-freedom system. [ABSTRACT FROM AUTHOR]

Discovery of new single-phase high-entropy alloys (HEAs) is important to understand HEA formation mechanisms. The present study reports computational design and experimental validation of a senary HEA, HfNbTaTiVZr, in a body-centered cubic structure. The phase diagrams and thermodynamic properties of this senary system were modeled using the CALPHAD method. Its atomic structure and diffusion constants were studied using ab initio molecular dynamics simulations. The microstructure of the as-cast HfNbTaTiVZr alloy was studied using X-ray diffraction and scanning electron microscopy, and the microsegregation in the as-cast state was found to qualitatively agree with the solidification predictions from CALPHAD. Supported by both simulation and experimental results, the HEA formation rules are discussed. [ABSTRACT FROM AUTHOR]