The Wide Field-of-View Cherenkov Telescope Array (WFCTA) and the Water Cherenkov Detector Array (WCDA) of LHAASO are designed to work in combination for measuring the energy spectra of the cosmic ray ...species over a very wide energy range from a few TeV to 10 PeV. The energy calibration can be achieved with a proven technique of measuring the westward shift of the Moon shadow cast by galactic cosmic rays due to the geomagnetic field. This deflection angle Δ is inversely proportional to the cosmic ray rigidity. The precise measurement of the shifts by WCDA allows us to calibrate its energy scale for energies as high as 35 TeV. Through a set of commonly triggered events, the energy scales can be propagated to WFCTA. The energies of the events can be derived both by WCDA-1 and WFCTA with the median energies 23.4 ± 0.1 ± 1.3 TeV and ( 21.9 ± 0.1 TeV ), respectively, which are consistent within uncertainties. In addition, the propagation of the energy scale is also validated by the Moon shadow based on the same data selection criteria of the commonly triggered events. This paper reports, for the first time, an observational measurement of the absolute energy scale of the primary cosmic rays generating showers observed by air Cherenkov telescopes.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Formal safety assessment (FSA), as a structured and systematic risk evaluation methodology, has been increasingly and broadly used in the shipping industry around the world. Concerns have been raised ...as to navigational safety of the Yangtze River, China's largest and the world's busiest inland waterway. Over the last few decades, the throughput of ships in the Yangtze River has increased rapidly due to the national development of the Middle and Western parts of China. Accidents such as collisions, groundings, contacts, oil-spills and fires occur repeatedly, often causing serious consequences. In order to improve the navigational safety in the Yangtze River, this paper estimates the navigational risk of the Yangtze River using the FSA concept and a Bayesian network (BN) technique. The navigational risk model is established by considering both probability and consequences of accidents with respect to a risk matrix method, followed by a scenario analysis to demonstrate the application of the proposed model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Melatonin and its receptors have been detected in the ovary of many species, and mediate ovarian functions. The present study was designed to investigate the expression and subcellar location of ...melatonin receptors in bovine granulosa cells (GCs), using reverse transcription (RT) polymerase chain reaction, Western blot, and immunofluorescence analyses. Furthermore, expression level of melatonin receptors mRNA (real-time polymerase chain reaction) after treatment with various concentrations of melatonin, as well as its effects on cell apoptosis, proliferation, and steroidogenesis (by flow cytometry and RIA), were determined. In bovine GCs, melatonin receptors MT1 and MT2 were differentially located at the cell membrane, the cytoplasm, and nuclear membranes. The expression of MT1 and MT2 mRNA was regulated differently by melatonin in time- and dose-dependent manners. Exogenous melatonin suppressed cell apoptosis (P < 0.05) but not proliferation (P > 0.05). After 72 h, the apoptotic rate was significantly inhibited in all treatment groups. Meanwhile, melatonin supplementation stimulated progesterone production, but inhibited estradiol biosynthesis, in a time-dependent manner. Progesterone production was highest (P < 0.05) at 72 h. Estradiol concentrations were almost unaffected (P > 0.05) at 24 h, but were decreased (P < 0.05) at 48 h. In conclusion, exogenous melatonin acts via receptors and has important roles in regulation of development and function of bovine GCs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Aim To investigate the potential of iodine concentration (IC) determined using virtual monochromatic spectral computed tomography (CT) to predict the response of gastric carcinomas to preoperative ...neoadjuvant chemotherapy (NC). Materials and methods A total of 20 patients were enrolled who underwent two spectral CT examinations (1 week before and two cycles after NC). The percentage change in tumour thickness (%ΔCWT) and in IC on the arterial phase (%ΔIC-a) and venous phase (%ΔIC-v) after NC were calculated and compared for different histopathological regression grades and response groups. The diagnostic efficacies to discriminate good response (GR) and poor response (PR) of the above three parameters were evaluated using receiver operating characteristic (ROC) curves. Results The decrease rate of %ΔIC-a for the GR group was higher than that for the PR group (−0.59 −0.76, −0.20 versus −0.11 −0.75, 0.92, p =0.012). There was no significant difference in the %ΔIC-v and %ΔCWT values between the GR and PR groups ( p =0.076 and p =0.779, respectively). The areas under the ROC curve (AUC) values were 0.857, 0.762, and 0.542 for %ΔIC-a, %ΔIC-v, and %ΔCWT, respectively, in the response prediction. The cut-off value for identifying PR was a decrease rate of <52.9% for %ΔIC-a, and the sensitivity and specificity values were 0.857 and 0.833. Conclusion Changes in the IC for gastric carcinomas following NC were detected using spectral CT and correlated with histopathological regression. The prediction efficacy for IC was better than that for tumour thickness, with IC on the arterial phase being a better predictor than IC on the venous phase.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Esophageal adenocarcinoma (EAC) has high mortality and is increasing in incidence. Barrett's esophagus (BE) increases the risk for EAC. Studies have reported inconsistent findings on the association ...between use of cyclooxygenase (COX) inhibitors and the risk of neoplastic progression in BE patients. Therefore, we performed a meta-analysis to investigate this association.
A meta-analysis was undertaken among a total of 9 observational studies using fixed- and random-effects models, comprising 5446 participants; 605 had EAC or high-grade dysplasia (HGD).
Overall, COX inhibitors use was associated with a reduced risk of EAC/HGD among BE patients (relative risk (RR)=0.64, 95% confidence interval (CI)=0.53-0.77). Aspirin use also reduced the risk of EAC/HGD (RR=0.63, 95% CI=0.43-0.94), as well as non-aspirin COX inhibitors (RR=0.50, 95% CI=0.32-0.78). The chemopreventive effect seemed to be independent of duration response.
Cyclooxygenase inhibitors use is associated with a reduced risk of developing EAC in patients with BE. Both low-dose aspirin and non-aspirin COX inhibitors are associated with a reduced risk of neoplasia. More well-designed randomised controlled trials are needed to increase our understanding of the chemopreventive effect of COX inhibitors.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Multifunctional materials with more than two good properties are widely required in modern industries. However, some properties are often trade-off with each other by single microstructural ...designation. For example, nanostructured materials have high strength, but low ductility and thermal stability. Here by means of spark plasma sintering (SPS) of nitrided Ti particles, we synthesized bulk core-shell structured Ti alloys with isolated soft coarse-grained Ti cores and hard Ti-N solid solution shells. The core-shell Ti alloys exhibit a high yield strength (~1.4 GPa) comparable to that of nanostructured states and high thermal stability (over 1100 °C, 0.71 of melting temperature), contributed by the hard Ti-N shells, as well as a good plasticity (fracture plasticity of 12%) due to the soft Ti cores. Our results demonstrate that this core-shell structure offers a design pathway towards an advanced material with enhancing strength-plasticity-thermal stability synergy.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Passive films at stainless steel bend under erosion-corrosion conditions are n-type semiconductor.•Donor density of point defects within passive film is higher at the extrados of the stainless steel ...bend.•Diffusivity of point defects is faster at the extrados of the bend.•The passive layer at the extrados of bend contains less Fe3O4 and Fe2O3.
Semiconductivities of passive films at a stainless steel bend in sand-containing NaCl solution under erosion-corrosion (E-C) conditions were investigated by Mott-Schottky analysis. It is demonstrated that higher donor densities and faster diffusivities of point defects within passive film appear at the extrados of the bend. X-ray photoelectron spectroscopy (XPS) analysis reveals that the passive layer at the extrados of bend contains less Fe3O4 and Fe2O3. The semiconductivities of passive films are strongly dependent on the hydrodynamic characteristics at the bend.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Aluminum bronze coatings with five different contents of Fe and Ni were successfully prepared on 316 stainless steel by laser cladding, aiming at improving wear resistance. Constituent phases, ...microstructure, microhardness and wear resistance of aluminum bronze coatings with different Fe and Ni contents were investigated using XRD, OM, SEM, EDS, microhardness tester and pin-on-disk wear-testing machine, respectively. Experimental results show that with appropriate laser processing parameters, the coatings are uniform and dense, in addition to good metallurgical bonding to the substrate. The coatings mainly consist of α-Cu matrix, γ2, β′, Cr-Fe and κ phase. The formation of these phases is explained in terms of the principles of thermodynamic metallurgy. The number of Cr-Fe phases increases with the addition of Fe and Ni, leading to the increase the heterogeneous nucleation sites and refining the microstructure. The microhardness of Cu-7Al-5Fe-5Ni coating is the highest, up to 281 ± 13 HV0.3, while the Cu-7Al-1Fe-1Ni coating with microhardness of 244 ± 12 HV0.3 exhibits the highest wear resistance. This phenomenon could be attributed to the fact that adding excess Fe and Ni into aluminum bronze would easily make hard reinforcing phases detach from the matrix and become debris, which could penetrate into the matrix and make lots of material loss, thus accelerating the wear process.
•Aluminum bronze coatings with various Fe and Ni have been prepared successfully.•Mechanism of formation of κ and globular Cr-Fe reinforced phases was discussed.•Microhardness was significantly improved due to the existence of κ and Cr-Fe.•The wear resistance was improved firstly and then declined with Fe and Ni added.•Wear resistance mechanisms for aluminum bronze coatings were investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
CuO nanowires were prepared on the copper foil by thermal oxidation in air. The effect of annealing temperature and growth time on the morphology of the nanowires is investigated. It is found that ...the annealing temperature and the growth time play an important role in the morphology of CuO nanowires such as the density, the length and the diameter. The length and the density of nanowires increase with prolonging growth time; but if the time is too long, CuO crystallite grains form instead of nanowires. Annealing copper foils at lower or higher temperature, the density of nanowires is lower. For comparison, the Cu films on Si substrate deposited by direct current (dc) magnetron sputtering are oxidized, but we do not find large-scale of nanowires. The possible mechanism is also discussed for the growth of CuO nanowires.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Genetic variants in the pharmacokinetic (PK) mechanism are the main underlying factors affecting the antiplatelet response to clopidogrel. Using a genomewide association study (GWAS) to identify new ...genetic loci that modify antiplatelet effects in Chinese patients with coronary heart disease, we identified novel variants in two transporter genes (SLC14A2 rs12456693, ATP‐binding cassette ABCA1 rs2487032) and in N6AMT1 (rs2254638) associated with P2Y12 reaction unit (PRU) and plasma active metabolite (H4) concentration. These new variants dramatically improved the predictability of PRU variability to 37.7%. The associations between these loci and PK parameters of clopidogrel and H4 were observed in additional patients, and its function on the activation of clopidogrel was validated in liver S9 fractions (P < 0.05). Rs2254638 was further identified to exert a marginal risk effect for major adverse cardiac events in an independent cohort. In conclusion, new genetic variants were systematically identified as risk factors for the reduced efficacy of clopidogrel treatment.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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