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Background: Salivary adenoid cystic carcinoma (SACC) is one of the most common malignant cancers of the salivary gland, and 32.4-72.0% of SACC cases exhibit neural invasion (NI); however, the molecular mechanism underlying the high invasion potential of SACC remains unclear. Methods: The present study investigated the role of epidermal growth factor receptor (EGFR) in the AKT inhibition- or mitogen-activated protein kinase kinase (MEK)-induced NI and epithelialmesenchymal transition (EMT) in SACC cells using EGFR, PI3K, and MEK inhibitors. SACC-83 cell viability was assessed using an MTT assay, and a wound healing assay was performed to evaluate cell migration. Immunohistochemical staining with streptavidin peroxidase was used to detect the positive expression rate of EMT, AKT, phosphorylated (p)-AKT, ERK, and p-ERK proteins. The impact of EGFR, PI3K, and MEK inhibitors on tumor growth and NI was examined in a xenograft model in nude mice. Results: EGF and EGFR are effective in increasing cell viability, migration, and invasion. SACC metastasis is affected by the PI3K/AKT and MEK/ERK pathways, both of which are initiated by EGF/EGFR. The EMT and NI are regulated by the EGF/EGFR, PI3K/AKT, and MEK/ERK pathways. The present findings demonstrate the importance of suppressed EGFR/AKT/MEK signaling in NI in SACC by neural-tumor co-culture in vitro. Furthermore, our preclinical experiment provides solid evidence that injection of EGFR, PI3K, and MEK inhibitors suppressed the tumor growth and NI of SACC cells in nude mice. Conclusion: It was identified that inhibitors of EGFR, PI3K/AKT or MEK/ERK suppressed the proliferation, migration, and NI of SACC-83 cells via downregulation of the PI3K/AKT or MEK/ERK pathways. It was also demonstrated that inhibition of EGFR abolishes EMT in SACC by inhibiting the signaling of PI3K/AKT and MEK/ERK. The present results suggest the potential effectiveness of targeting multiple oncogenes associated with downstream pathways of EGF/EGFR, as well as potential therapeutic targets to limit NI in SACC by PI3K/AKT or MEK/ERK inhibition.

Different from previous linguistic studies on rhetoric, which primarily concern the ideational semantics and the logic of sentences, this article attempts to deal systematically with the interpersonal semantics of rhetoric by drawing on the comprehensive appraisal framework of systemic functional linguistics (Martin and White 2005) and explores the mechanism of rhetorical persuasion in science communication via appraisal through a case study of the gene-modification (GM) debate in China. It first examines the rhetorical appeals of the subsystems of appraisal and then based on a self-constructed and coded corpus of GM debate discourses, it compares how institutional (the Chinese Ministry of Agriculture and the Greenpeace Organization) and individual stakeholders (Cui Yongyuan and Fang Zhouzi) of different ideological interests in the GM debate mobilize the interpersonal semantic resources to rhetorical effects to persuade the audience of the safety/danger of the GM technology and products. The analysis reveals that while the opinion leaders choose ‘soft’ persuasion by heavily using affect and judgement resources, the institutions opt for ‘hard’ persuasion by utilizing more appreciation resources. The four parties all prefer contracting resources over expanding resources of engagement, which restricts the space of negotiation. Their communicative motives are interpreted through the lens of the rhetoric theory, and the implications and consequences for science communication in the post-truth era are discussed. Theoretically, the paper contributes to understanding the persuasion mechanism of appraisal and to understanding the science vs. society, and government vs. citizens relationship.

Graphene, with its excellent mechanical properties and electrical conductivity, has been considered as an effective reinforcement phase for copper matrix composites. However, due to its easy agglomeration and poor wetting properties in the copper matrix, it is difficult to simulataneously enhance strength, ductility and conductivity of graphene based copper composites using a low cost and efficient method. In this paper, we proposed a new methodology to use wheat flour as a solid carbon source to in-situ generate graphene-coated copper (Gr@Cu) composite powders. These powders were then used as strengthening phases to fabricate Gr@Cu copper composites through wet mixing and spark plasma sintering (SPS) processes. Results showed that not only high-quality graphene layer was obtained and serious agglomeration of graphene was avoided, but also a strong interfacial bonding between graphene and copper matrix was achieved. The fabricated composites showed excellent properties, e.g., a maximum density of 99, enhanced micro-hardness (15-22 higher than that of pure copper), and excellent strength/ ductility. The maximum tensile strength and yield strength were obtained in the 0.70 wt.Gr@Cu/Cu composites (e.g., 252 MPa and 132 MPa, respectively). These values are ~23 and ~110 higher than those of pure copper, and the elongation rate was maintained at ~30. In addition, the composites showed excellent conductivity.

Because of its high ductile-brittle transition temperature, tungsten (W) is normally alloyed with other metal elements in order to obtain high fracture strength, excellent thermal and electrical properties for industrial applications. For tungsten samples sintered using the conventional powder metallurgy methods, bonding among tungsten particles is normally through sintered necking process, thus without providing a good metallurgical bonding strength. In this paper, we proposed to apply additive manufacture methodology to synthesize two types of porous tungsten skeleton structures, honeycomb (65% porosity) and square skeleton (80% porosity), using a selective laser melting (SLM) method. Results showed that for both these skeleton structures, grains in the XY plane showed an equiaxed crystal appearance, whereas those in the YZ/XZ plane showed columnar patterns parallel to the Z axis. The measured porosities for these two types of skeletons were 52 vol% and 68 vol%, and their compressive strength values were 256 MPa and 149 MPa, respectively. Both their compressive strengths and hardness showed anisotropic behaviors, with their highest values along the direction of Z axis. Results also showed that fracture morphology and mechanisms of these skeletons under compression were quite different when they were compressed along different directions, mainly due to the formed columnar crystals of the skeletons along the Z axis. Fracture morphology along the Z axis showed transgranular fracture and tearing features, whereas those along X axis showed only intergranular fracture features.

To explore the cumulative damage law of near-field underwater explosions on the side of the ship structure, the multi-cabin model of the shipboard local structure is designed and applied to close-in underwater explosion experiments with different explosive masses and model conditions. The pressure load of the explosion shock wave near the water surface is obtained and analyzed. The damage results, such as the damage pattern of the model and the damage range of cabins, are acquired. The comprehensive comparison shows that: the secondary explosion on the side has a significant cumulative damage effect; the damage pattern of the structure is closely related to the proportional distance of the explosion. The damaged power of a single large charge explosion on the shipboard is bigger than the cumulative damage caused by two small explosions. The results of this study can provide a reference for the research on the damage and protection of the ship.

Salivary adenoid cystic carcinoma (SACC) is one of the most common malignant cancers of the salivary gland, and 32.4-72.0% of SACC cases exhibit neural invasion (NI); however, the molecular mechanism underlying the high invasion potential of SACC remains unclear.The present study investigated the role of epidermal growth factor receptor (EGFR) in the AKT inhibition- or mitogen-activated protein kinase kinase (MEK)-induced NI and epithelialmesenchymal transition (EMT) in SACC cells using EGFR, PI3K, and MEK inhibitors. SACC-83 cell viability was assessed using an MTT assay, and a wound healing assay was performed to evaluate cell migration. Immunohistochemical staining with streptavidin peroxidase was used to detect the positive expression rate of EMT, AKT, phosphorylated (p)-AKT, ERK, and p-ERK proteins. The impact of EGFR, PI3K, and MEK inhibitors on tumor growth and NI was examined in a xenograft model in nude mice.EGF and EGFR are effective in increasing cell viability, migration, and invasion. SACC metastasis is affected by the PI3K/AKT and MEK/ERK pathways, both of which are initiated by EGF/EGFR. The EMT and NI are regulated by the EGF/EGFR, PI3K/AKT, and MEK/ERK pathways. The present findings demonstrate the importance of suppressed EGFR/AKT/MEK signaling in NI in SACC by neural-tumor co-culture in vitro. Furthermore, our preclinical experiment provides solid evidence that injection of EGFR, PI3K, and MEK inhibitors suppressed the tumor growth and NI of SACC cells in nude mice.It was identified that inhibitors of EGFR, PI3K/AKT or MEK/ERK suppressed the proliferation, migration, and NI of SACC-83 cells via downregulation of the PI3K/AKT or MEK/ERK pathways. It was also demonstrated that inhibition of EGFR abolishes EMT in SACC by inhibiting the signaling of PI3K/AKT and MEK/ERK. The present results suggest the potential effectiveness of targeting multiple oncogenes associated with downstream pathways of EGF/EGFR, as well as potential therapeutic targets to limit NI in SACC by PI3K/AKT or MEK/ERK inhibition.

Co3O4 is a good anode candidate for high-performance lithium ion batteries (LIBs), attributed to its high specific capacity. However, due to its poor conductivity and significant volume expansion during electrochemical reactions, electrochemical performance of Co3O4 electrode is quite poor for practical applications. Co3O4 electrodes with various micro-/nanostructures have been designed and synthesized but their performances are still unsatisfied. In this study, we propose and develop a novel sandwich type of Co3O4 nanostructures by adjusting the ratio of ammonium fluoride and urea during hydrothermal reactions. When this sandwich-like Co3O4 composite electrode was used as the electrode for LIBs, it retained an outstanding reversible capacity of 857 mAh g−1 after 70 cycles at a current density of 500 mA g−1. When the current density was increased to 1000 mA g−1, the reversible capacity was kept at 865 mAh g−1 with insignificant changes of its capacity.

The Institute of Plasma Physics at the Chinese Academy of Sciences is developing the REBCO cable in conduit conductor (CICC) technology for applications in next-generation nuclear fusion devices. The aim is to develop a CICC comprised of six REBCO sub-cables to satisfy the requirements of operation with a current of around 40 kA and a peak field of up to 20 T. To qualify the performance of the sub-size REBCO cable to be used in the CICC, two 25-turn insert solenoids have been designed, manufactured and tested at a current exceeding 6 kA subjected in a background field supplied by a water-cooled resistive magnet. The insert solenoid, wound from a 11.5 m long REBCO CORC® cable, was designed to investigate its current carrying capacity under high field and electromagnetic (EM) load at 4.2 K. Tests were performed under a background magnetic field up to 18.5 T, resulting in a peak magnetic field on the innermost layer turns of around 21.1 T at an operating current of 6.3 kA. The effects of operation with cyclic EM loads were tested by repeated current ramps to around 95% of the critical current. Moreover, the V–I characteristics were measured at 77 K and the self-field, to check the effects from warm-up and cool-down (WUCD) cycles between room temperature and 77 K with liquid nitrogen. The results show no obvious degradation after dozens of high-current test cycles in background fields ranging from 10 T to 18.5 T. The insert solenoid demonstrates the stable operation of the REBCO sub-size cable for CICC with EM loads of about 90 kN m−1 and WUCD cycles between room temperature and 77 K. These promising results indicate the potential of this technology for further applicationsin particular, for full-size CICC for high-performance fusion magnets.

High magnetic fields play a critical role in the development of modern science and technology, breeding many significant scientific discoveries and boosting the generation of new technologies. In the last few years, China has undertaken a great deal of work on the application of ultra-high-field (UHF) superconducting magnet technology, such as for the Synergetic Extreme Condition User Facility in Beijing, the UHF nuclear magnetic resonance/magnetic resonance imaging, nuclear fusion energy, particle accelerator, and so on. This paper reports the research status of UHF superconducting magnets in China from different perspectives, including design options, technical features, experimental progress, opportunities, and challenges.

Benzotriazole (BTA) and tolyltriazole (TTA) were used to passivate pure copper and chromium bronze alloys for environmental protection. Using the chemical immersion treatment, a dense film of chromium-free passivation layer was formed on surfaces of both the pure copper and chromium bronze alloys. Microstructure, crystalline phases and chemical bonds of the passivation layers were systematically characterized, and the passivation mechanisms were studied. The passivation layer was mainly consisted of CuO, Cu2O, polymers of Cu-BTA-TTA and Cu(I)BTA-TTA. The formation mechanism of the chromium-free passivation layer was identified as combined oxidation and adsorption, and the main passivation processes included oxidation and dissolution of the matrix, adsorption of BTA and its derivatives, self-stabilization process of the adsorbed film, and filling of passivation film’s voids by oxide particles.