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The Al/Al2O3 composite deuterium barrier was deposited on the polished side of 316 L stainless steel by the method of radio-frequency magnetron sputtering. The influence of the introduction of Al transition layer on the deuterium resistance performance of Al2O3 ceramic coating was studied. The field emission scanning electron microscope (SEM), the grazing incident X-ray diffraction technique (GIXRD), and the auger electron spectroscopy (AES) were used to analyze the microscopic morphology, phase, and element distribution in the depth direction of the Al/Al2O3 coating, and the gas-driver permeation method was used to measure the deuterium permeation behavior of the coating sample. The results show that Al2O3 is amorphous after annealing at 873 K. Due to the oxidation of the Al transition layer, the connection between the coating and the substrate is tightly connected. Under the combined action of permeation temperature and pressure of 873 K and 80 kPa, the deuterium permeability of Al/Al2O3 coating is 6.35 × 10 − 14 mol·m-1·s-1·Pa-0.5, which shows that the Al/Al2O3 coating has excellent deuterium permeation resistance. Furthermore, deuterium permeability of the Al/Al2O3 coating was diminished by about 2 orders of magnitude compared with 316 L stainless steel, and it is reduced 2~3 times compared with the single Al2O3 coating sample. The study indicates that the introduction of the Al transition layer can significantly enhance the barrier effect of the Al/Al2O3 coating sample. [ABSTRACT FROM AUTHOR]

A deuterium permeation barrier is an essential part in the core component of nuclear reactors. It can protect the structure made of steel from being penetrated by deuterium in a fusion reactor. However, residual stress induced in the operation would dramatically influence the mechanical endurance of the coating, threatening the safety of the facilities. In this paper, finite element analysis was conducted to investigate the residual stress in nanoscale Al2O3 and Y2O3 coatings and their composites under thermal shock, from 700°C to 25°C. The max principal stress is assumed as the cause of crack initiation in the coating, because ceramics are brittle and fragile under tensile stress. Max shear stress and max Mises stress in the systems are also analyzed, and the effect of thickness in the range 100 nm to 1000 nm was investigated. The max principal stress in Al2O3 coating reaches its maximum value, 1.33 GPa, when the thickness of coating reaches 450 nm. And the max principal stress decreases at a very low rate as the thickness increases exceeding 450 nm. The max principal stress in Y2O3 coating increases rapidly as the thickness increases when the thickness of the coating is below 250 nm, and the max principal stress is at about 0.9 GPa when the thickness exceeds 500 nm. The max principal stress in the Y2O3/Al2O3 (150 nm) composite coating occurs in the Al2O3 layer and shows no difference from the single layer of 150 nm thick Al2O3 coating. The max principal stress site of all three kinds of coating is located at the edge of the coating 25 nm away from the interface. The result shows that residual thermal stress in the coating increases as the thickness increases when the thickness of the coating is below 200 nm due to the stress singularity of the interface. And as the thickness exceeds 500 nm, the increase in thickness has little impact on the residual thermal stress in the coating. Coating an Y2O3 top layer will not introduce any more residual thermal stress under the thermal shock condition. The Y2O3 coating causes much less residual stress under thermal shock compared with Al2O3 owing to its much lower Young's modulus. The max principal stress in the 300 nm thick Y2O3 coating is 0.85 GPa while that of the Al2O3 coating is 1.16 GPa. The max residual stress of the composite Y2O3/Al2O3 (150 nm) coating is determined by the Al2O3 layer. [ABSTRACT FROM AUTHOR]

Purpose: Regulation of gene expression is fine-tuned by a dynamic equilibrium between repressive modifications and transcriptional activation of histone tails. Jumonji domain-containing 3 (Jmjd3), also known as KDM6B, is a specific histone demethylase for trimethylation on histone H3 lysine 27 (H3K27me3) that specifically removes the methylation of H3K27me3 and promotes gene expression. Our previous study showed that Jmjd3 inhibits serum deprivation-induced osteoblast apoptosis. In this study, we clarified the role of Jmjd3 in tumor necrosis factor-alpha (TNF-α)-induced osteoblast apoptosis. Materials and Methods: Jmjd3 activity was inhibited by GSK-J4. Transfection of osteoblastic murine MC3T3-E1 cells with short hairpin RNA (shRNA) was used to establish stable Jmjd3 knockdown cells. Osteoblast apoptosis was detected using Annexin V-APC/PI staining, cysteinyl aspartate specific protease-3 (caspase-3) activity assays, and Western blot. Real-time polymerase chain reaction (PCR) and chromatin immunoprecipitation (ChIP) assays were performed to clarify the mechanism responsible for Jmjd3-regulated osteoblast apoptosis induced by TNF-α. Results: Based on Annexin V-APC/PI staining, caspase-3 activation, and poly ADP-ribose polymerase (PARP) cleavage, pretreatment with GSK-J4 and knockdown of Jmjd3 by shRNA transfection each inhibited osteoblast apoptosis. Furthermore, knockdown of Jmjd3 decreased the expression of Ras association domain family 5 (RASSF5), which is a pro-apoptotic gene of the Ras associated domain family. H3K27me3 levels in the promoter region of RASSF5 were up-regulated in the Jmjd3 knockdown cells. Conclusions: Jmjd3 regulated TNF-α-induced osteoblast apoptosis by targeting RASSF5. [ABSTRACT FROM AUTHOR]

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Cu2ZnSnS4 thin films were prepared by co-sputtering with Cu (or Cu2S), ZnS and SnS2 targets in this study. S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target. The effect of S amount in the precursor on the microstructure and element distribution of Cu2ZnSnS4 thin film was discussed. It was found that S content is sufficient in the precursor thin film using Cu2S instead of Cu target. The microstructure, composition homogeneity, and secondary phase formation of the Cu2ZnSnS4 thin film are seriously affected by S amount in the precursor thin film. Namely, sufficient S can improve the crystallization and orientation of the precursor thin film and enhance the compactness as well as composition homogeneity of the Cu2ZnSnS4 thin film after sulfurization. Moreover, the secondary phase formation in Cu2ZnSnS4 thin film can be greatly inhibited by increasing S content in the precursor thin film. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to evaluate the efficacy and safety of gemcitabine plus cisplatin concurrent chemoradiotherapy (CCRT) in patients with nasopharyngeal carcinoma.Method: Patients with NPC were randomly assigned to the gemcitabine plus cisplatin (GP) group or fluorouracil plus cisplatin (PF) group. Primary end-point was disease-free survival (DFS); secondary endpoints: overall survival, distant metastasis-free survival (DMFS), locoregional relapse-free survival, and treatment-related adverse events.Results: Seventy-six patients were prospectively enrolled and the median follow-up time was 41 months (9-61 months). Three-year DFS were similar between the GP and PF groups (73.7% vs. 60.5%, HR 0.66, 95% CI 0.30-1.44; P = 0.30). Distant metastasis was the most common failure form in PF compared with GP (P = 0.034). Three-year DMFS was significantly better in the GP group than PF group (89.5% vs. 71.1%, P = 0.045). Grade 3-4 gastrointestinal toxicities (vomiting and diarrhea) were significantly more common in the PF group; grade 3-4 neutropenia and thrombocytopenia were more common in the GP group.Conclusion: Gemcitabine plus cisplatin could be used as an alternative regimen in CCRT for nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

Pedestrian trajectory prediction is an increasingly important research area in applied autonomous driving and social robotics. Effectively modeling the intricate interactions between pedestrians is paramount for improving trajectory prediction accuracy. However, when using Graph Neural Networks(GNNs) to model these interactions, fixed interactions tend to remain, preventing the graph model from making adaptive adjustments and thus resulting in significant discrepancies between the predicted and true trajectories. In this study, we propose a Dynamic-Evolving Relative Graph Convolutional Network(DERGCN) to predict the future trajectories of pedestrians. The network model captures the dynamically evolving pedestrian interactions and incorporates an evolving mechanism to simulate them. In addition, with a relative temporal encoding strategy employed to improve the dynamics of the graph further, our policy network yielded an improved predictive performance when tested on two challenging datasets. [Display omitted] • A trajectory forecasting framework with a dynamic graph is proposed. • A continuously evolving mechanism is proposed to model interactions between humans. • The continuously evolving mechanism is to model structural temporal dependencies. • The results reveal that our model has a superior prediction performance. [ABSTRACT FROM AUTHOR]

Our current understanding of the repercussions stemming from long-term temperature variability (TV) within the broader context of global climate change remains considerably limited. This study aims to investigate the influence of long-term temperature variability on the probability of death and mortality among stroke patients. For this study, a sample of stroke patients aged 40 years and above between 2016 and 2019 was taken from five districts/counties in central Shandong Province. We calculated the standard deviation (SD) of the annual mean daily temperature and the annual mean diurnal temperature range (DTR) obtained from the baseline survey to express the long-term TV. To assess the link between TV exposure and mortality among stroke patients, we utilized the Cox proportional hazards regression method. This statistical method allowed us to estimate the adjusted hazard ratio (HR) and 95 % confidence interval (CI) with regard to the risk of mortality. For stroke patients, there was a correlation between a 1 °C rise in the SD of temperature and an elevated risk of mortality (HR: 1.18, 95 % CI: 1.08–1.29). Additionally, each 1 °C increase in the DTR was associated with a further increase in the risk of death (HR: 1.69, 95 % CI: 1.59–1.79). In patients diagnosed with ischemic and hemorrhagic stroke, DTR was found to be positively associated with the risk of death. Temperature SD was found to be positively associated with the risk of death only in patients with ischemic stroke. Persistent exposure to TV was strongly linked to mortality risk among individuals with stroke. By devoting increased attention to TV, these organizations can develop strategies to mitigate its adverse effects on public health. [Display omitted] • Long-term temperature variability increases risk of death in stroke patients. • Stroke type affects patient death in relation to long-term temperature variability. • The effect of TV on death in stroke patients differs in different age groups. [ABSTRACT FROM AUTHOR]