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As one of CFETR’s candidate blankets, water cooled ceramic breeder (WCCB) blanket undertakes important nuclear-related functions such as tritium breeding, nuclear heat extraction, and neutron shielding. The reliability of neutronics design directly affects the realization of CFETR tritium self-sustaining goal. In order to verify the reliability of the neutronics design tool, i.e. MCNP and FNEDL databases, in the WCCB blanket neutronics design, the WCCB scaling-down mock up was developed to carry out the neutronics experiment in the DT neutron environment, including two layers of lithium titanate, two layers of beryllium, three layers of cooling plate, and one layer of tungsten armor. The neutronics performance of the mock up are similar with the real blanket module. The mock up neutronics experiments were carried out using DT neutron generator, the simulated value (C) and experimental value (E) of neutronics parameters represented by tritium production rate (TPR) were analyzed. For TPR validation, two independent detection technologies were used, including the Li2TiO3 pellets as off-line TPR detectors, and the developed lithium glass detectors as on-line TPR detectors. The TPR validation was complemented by evaluating the predicted neutron-induced reaction rates of the Au, Zr foils. The experiments on the mock up were analyzed by MCNP-4C code and FENDL-3.0 nuclear data libraries, and the source term for Monte Carlo simulation was built using the custom-developed model based on depth profiling of tritium in the tritide target. The analysis results show that the C/E of TPR in the axis of two lithium titanate layers is 0.97 and 1.08 respectively, while there is a large deviation between the calculated and experimental values of TPR in the edge region of the mock up. According to the experimental results from Li2TiO3 pellets, the C/E of TPR at the edge of two lithium titanate layers is 0.65 and 0.82, respectively. The TPR is obviously underestimated by simulation at the edge of lithium titanate layers, confirmed by the C/E results of 197Au(n, γ)198Au reaction rate at the edge of lithium titanate layers, which are 0.72 and 0.90, respectively. It is indicated that there are unexpected scattered neutrons in the edge region of the mock up, resulting in the higher TPR than expected. The further experiments are needed to verify the influence of the scattered neutron on the TPR at the edge region of the mock up. To investigate the TPR gap between simulation and the experimental results from lithium glass detectors, the contribution of the fast neutrons on the 6Li(n, t)4He should be further studied. Also the other suggestions are provided for further experimental research, refering to the radiation protections and nuclear measurements.

Introduction: Ultrasound sonography provides a quick method for determining which nodule to sample for fine needle aspiration biopsy in thyroid nodules. On the other hand, the computed tomography examination is not restricted by echo attenuation and distinguishes between benign and malignant nodules. Objective: To compare computed tomography examinations against ultrasound/fine needle aspiration biopsy in the differential diagnosis of thyroid nodules. Methods: Data regarding computed tomography examinations, sonographic finding following fine needle aspiration biopsy, and tumor histology of 953 nodules from 698 patients who underwent thyroidectomy were collected and analyzed. The beneficial score for detection of the malignant tumor for each adopted modality was evaluated. Results: Ultrasound images did not show a well-circumscribed solid mass in 89 nodules, and ultimately did not detect nodules in fine needle aspiration biopsies (false positive non-malignant nodules). Ultrasound images showed parenchymatous disease (false positive malignant nodules) in several nodules. Computed tomography examinations demonstrated higher difficulty in detection of malignant nodules of 1.0–2.0 cm size than ultrasound examination following fine needle aspiration biopsies; compared to tumor histological data, computed tomography examinations had a sensitivity of 0.879. Conclusion: Computed tomography examinations are a more reliable method for differential diagnosis of thyroid nodules than ultrasound examinations followed by fine needle aspiration biopsy. Level of Evidence: III.

Chalcone (1,3-diaryl-2-propen-1-one) is an α, β-unsaturated ketone that serves as an active constituent or precursor of numerous natural substances, exhibiting a broad spectrum of pharmacological effects. In this study, the classical Claisen–Schmidt condensation method was used to synthesize the chalcone derivative 2′,4′-dimethoxychalcone (DTC) and evaluate its pharmacological activity. By upregulating the expression of the epithelial cell marker E-cadherin and downregulating the expression of the mesenchymal cell marker vimentin, DTC was found to inhibit transforming growth factor-β1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) process in A549 cells, maintaining the cells' epithelial-like morphology and reducing the ability of the cells to migrate. Additionally, DTC demonstrated the ability to decrease the expression levels of nitric oxide (NO), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in RAW264.7 cells, suggesting a possible anti-inflammatory effect. Furthermore, DTC was found to exhibit bacteriostatic activity against Staphylococcus aureus (S. aureus), Proteus vulgaris (P. vulgaris), methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans (C. albicans), indicating that this chemical may possess broad-spectrum antibacterial activity. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis (PF) is a disease characterised by diffuse nonspecific alveolar inflammation with interstitial fibrosis, which clinically manifests as dyspnoea and a significant decline in lung function. Many studies have shown that the epithelial–mesenchymal transition (EMT) plays a pivotal role in the pathogenesis of pulmonary fibrosis. Based on our previous findings, hypericin (Hyp) can effectively inhibit the process of the EMT to attenuate lung fibrosis. Therefore, a series of hyperoside derivatives were synthesised via modifying the structure of hyperoside, and subsequently evaluated for A549 cytotoxicity. Among these, the pre-screening of eight derivatives inhibits the EMT. In this study, we evaluated the efficacy of Z6, the most promising hyperoside derivative, in reversing TGF-β1-induced EMTs and inhibiting the EMT-associated migration of A549 cells. After the treatment of A549 cells with Z6 for 48 h, RT-qPCR and Western blot results showed that Z6 inhibited TGF-β1-induced EMTs in epithelial cells by supressing morphological changes in A549 cells, up-regulating E-cadherin (p < 0.01, p < 0.001), and down-regulating Vimentin (p < 0.01, p < 0.001). This treatment significantly reduced the mobility of transforming growth factor β1 (TGF-β1)-stimulated cells (p < 0.001) as assessed by wound closure, while increasing the adhesion rate of A549 cells (p < 0.001). In conclusion, our results suggest that hyperoside derivatives, especially compound Z6, are promising as potential lead compounds for treating pulmonary fibrosis, and therefore deserve further investigation. [ABSTRACT FROM AUTHOR]

A visible‐light‐mediated decarboxylative oxidation of benzylic redox active esters is described. A diverse array of aromatic ketones or aldehydes could be achieved (15 examples) from secondary or primary aliphatic carboxylic acids. A mechanism involving resonance transformation in the presence of Cs2CO3 is proposed. [ABSTRACT FROM AUTHOR]

The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. These composites have tunable metal oxide contents, large surface areas, and wide mesopores. The combination of Nb2O5 nanoparticles (NPs) with SiO2 results in an increased surface area and a larger number of acid sites compared to pure Nb2O5 NPs. The surface texture and acidity of the silica–niobia composites can be tuned by adjusting the Nb/Si molar ratio. Moreover, the silica provides protection to the niobia NPs, preventing sintering during thermal treatment at 400 °C. The silica–niobia materials exhibit superior performance as catalysts in the aldol condensation of furfural (Fur) with acetone compared to pure niobia, leading to an up to 62% in product yield. Additionally, these catalysts show remarkable stability, retaining their performance over multiple runs. This work demonstrates the potential of the proposed synthesis approach for preparing more sustainable, high-performance, durable, and stable nanoscale metal oxide-based catalysts with a tunable composition, surface area, and active site density. [ABSTRACT FROM AUTHOR]

Li‐rich manganese base oxides (LRNCM) are regarded as one of the most promising cathode materials among next‐generation high‐energy density Li‐ion batteries due to the coupling effect of anion and cation redox. However, serious oxygen release, surface structure corrosion, and transformation seriously damage their electrochemical performance and restrict their commercialization process. Herein, a dual gaseous surface treatment strategy with ammonium bicarbonate is designed to reconstruct the surface chemical and structural characteristics of LRNCM. As a result, an enriched oxygen vacancies mixed‐phase surface layer is achieved, which contains spinel phase and cation‐disordered phase. The integration of the surface mixed phase effectively inhibits irreversible oxygen loss, prevents electrode corrosion, and promotes fast Li‐ion diffusion. Accordingly, the modified cathode exhibits excellent specific capacity, high‐rate capability, and superior cycle life at both 25 and 60 °C. Particularly at high temperatures, it achieves impressive performance: initial coulombic efficiency (82.0 vs 74.4%), cycling stability at 1 C after 100 cycles (92.6 vs 83.8%), and rate performance at 5 C (56.0 vs 48.7%). This reconfiguration approach introduces a novel idea for the design of cathode material interfaces. [ABSTRACT FROM AUTHOR]

In this paper, high-throughput sequencing technology was adopted to visualize the microbial communities on the surfaces of two types of carbon steel immersed in Sea Area Ⅰ. The results showed that different microbial communities were formed on different carbon steel surfaces, in which the genus with the highest abundance on the surface of Q235 was Escherichia–Shigella, while anaerobic Desulfovibrio on the surface of 921a was the most abundant, and the dominant genus varied with the depth of the rust layer. In addition, the distribution of sulfate-reducing bacteria (SRB) on the surface of Q235 submerged in Sea Area Ⅱ was compared with the sulfate-reducing bacteria's distribution in Sea Area Ⅰ, using the environmental factors correlation analysis. The results showed that the concentrations of Ca2+, Na+, K+, Mg2+, and Al3+ were positively correlated with the distribution of SRB, while the concentrations of Cu2+, Zn2+, SO42−, Cl−, NO3−, and organic carbon were negatively correlated with it. Furthermore, there was a highly significant correlation between each geochemical factor and Desulfotomaculum (p < 0.01). [ABSTRACT FROM AUTHOR]

The coincidence of hatching and emergence events with favorable conditions is crucial for turtle survival. Nocturnal emergence has been widely documented across marine and freshwater turtles, and has long been suggested as an adaptive behavior that reduces risks of heat stress and predation. To our knowledge, however, studies related to nocturnal emergence have mainly focused on the post‐hatching behaviors of turtles, and very few experimental studies have been performed to investigate the effects of hatching time on the distribution of emergence times over the course of a day. Here, we visually monitored the activity of the Chinese softshell turtle (Pelodiscus sinensis)—a shallow‐nesting freshwater turtle—from hatching to emergence. Our study provides evidence for the novel finding that (i) the timing of synchronous hatching events in P. sinensis coincides with the time of day when nest temperatures decrease, (ii) the synchrony between hatching and emergence may further facilitate their nocturnal emergence, and (iii) synchronous behaviors of hatchlings in the nest may be effective in reducing the risk of hatchling predation, and predation is more likely to occur in the asynchronous hatching groups. This study suggests that the hatching of shallow‐nesting P. sinensis in response to temperature changes in the nest might be an adaptive nocturnal emergence strategy. [ABSTRACT FROM AUTHOR]