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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.

Since the initial identification of the iron-based superconductors (IBS) in 2008, numerous studies had focused on how to improve critical current density. However, the research of quench behaviors for iron-based multi-filamentary tapes was rarely reported. It is important to understand quench behaviors, and two main parameters should be examined carefully, i.e., normal zone propagation velocity (NZPV) and minimum quench energy (MQE). In this paper, a two-dimensional quench model integrating the stationary electrodynamics equations and heat conduction equation was proposed to study the quench propagation of iron-based Sr/Ba0.6K0.4Fe2As2 (Sr/Ba122) tape in different transport currents and temperatures. MQEs and NPZVs of IBS tape were calculated by the quench model, and the results were well complied with experimentally results which verified the correctness of the proposed quench model. In addition, since iron-based superconducting coils for high magnetic field application were operating in liquid helium mostly, an experiment was performed to study the quench behaviors of Ba122 tape in liquid helium, for the purpose of understanding the stability of the iron-based superconductor and designing quench protection systems of IBS coils reliably.

This is the second part of a two-part article which proposes an enhanced approach to eco-discourses after weighing the (dis)advantages of mainstream Critical Discourse Analysis (CDA) and Positive Discourse Analysis (PDA). Part I (Chen et al. 2021) explored the theoretical grounding for an enhanced PDA, introduced the research method and then, based on the adapted analytic framework of Stibbe (2016), undertook a critical analysis of the discourses of Shell Oil Company (SOC). Part II uses the same analytic framework to analyse Greenpeace USA’s (GPU) discourse and compare it to the SOC discourse. The emphasis in Part II is on the exploration of potential fissures in the discourses across difference, and the possible common grounds upon which to design alternative discourses that are empathetic, comprehensible and legitimate to a coalition of social forces. Practically, Part II finds that the two groups use similar discourse strategies, such as salience and framing, but with different orientations. Methodologically, Part II argues that corpus-aided comparative discourse analysis, with a focus on discourse semantics, will facilitate the identification of ‘greenwashing’ strategies that strengthen and stabilize current hegemonic social order. This part also points to avenues of alternative discourses which exploit the inherent contradictions or fissures within that hegemonic order. Theoretically, the paper suggests that within an enhanced Positive Discourse Analysis approach, it is also important to seek out points of convergence between progressive positions and to articulate these within a hybrid, counter-hegemonic discourse that maximizes its potential for uptake, while it destabilizes the prevailing discourses at precisely the fissure points identified.

A 13-T superconducting magnet for neutron scattering experiments was being developed at the High Magnetic Field Laboratory, Chinese Academy of Sciences, which will provide a high magnetic field environment to research condensed matter physics. It is made up of 6 Nb3Sn coils and 8 NbTi coils to provide a 13-T central magnetic field with 0.5% field inhomogeneity in the sample region of O10 mm×10 mm cylinder. Due to the horizontal opening angle of 320° and the vertical opening angle of ±8°, there is a very limited space for the support structure, which is expected to withstand an electromagnetic force of approximately 200 tons; as a result, the design of the support structure is crucial in order to avoid any harmful plastic deformation. In this paper, the electromagnetic solution, structure design, and mechanical analysis are mainly presented.

This two-part article suggests ways in which elements of antagonistic discourses of the environment might be combined in a hybrid, innovative discourse that appeals to a broad section of the public while advocating for more environmentally sustainable practices in industry. It proposes an enhanced Positive Discourse Analysis (PDA) that not only identifies points of fissure in the hegemonic discourse but also seeks points of convergence that can be articulated with in a hybrid, counter-hegemonic discourse that maximizes its potential for uptake while destabilizing the prevailing discourses at precisely the fissure points identified. Part I explores the theoretical grounding for an enhanced PDA, introduces the research method and then, based on Stibbe (2016), makes an eco-discourse analysis of discourses by Shell Oil Company (SOC), with a focus on their discourse semantic patterns, showcasing how hegemonic groups employ discourse strategies to serve their interests and what ecological effects such discourses may produce. In Part II (Chen et al. 2021), a comparative analysis is conducted on the SOC discourses and the Greenpeace discourses. As well as highlighting the points of antagonism between the two discourses, it attempts to seek out points of convergence between progressive positions in the discourses. Part II also explores the potential fissures in the hegemonic order and discusses the design of alternative discourses thereupon. It is argued that an enhanced PDA which focuses on solutions rather than problems and collaboration rather than resistance forms a route for positive and interventionist orientations to discourse that promote social change.

At present, it is critical to rationally design and facilely synthesize highly cost-effective multifunctional non-noble metal electrocatalysts for sustainable energy applications. Herein, a facile solid-phase precursor pyrolysis method is used to construct N-doped carbon nanotubes encapsulating Co nanoparticles (Co@NCNTs) as a multifunctional electrocatalyst. In this method, ZIF-67 and dicyandiamide are used as the precursor and CNT growth initiator, respectively. The systematic formation process of Co@NCNTs involves a morphological evolution process from nanododecahedras, nanospheres with sparse short nanotubes to nanotubes. Owing to the synergistic effects from the inner Co nanoparticles and outer NCNTs, Co@NCNTs exhibit high multifunctional performance for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Furthermore, a primary zinc–air battery based on Co@NCNTs also shows high activity and stability. Therefore, Co@NCNTs will be a potential multifunctional catalyst for application in sustainable energy systems.

The Conductor on Round Core (CORC®) cable is a type of high-temperature superconducting cable that is suitable for power transmission with high current density, accelerator magnets, and high field magnet devices. The CORC cable wound with RE-Ba2Cu3O7−δ (REBCO) tapes around a central metallic core can offer isotropic flexibility and good stability. In this paper, two kinds of tapes from different manufactures were selected to study the effect of the winding parameters (winding angle, former diameter, thickness of the superconducting tape, and width of the superconducting tape) on the critical performance of a single-layer CORC high-temperature superconducting cable. Based on the experimental results, a fitting equation was proposed to evaluate the critical current of the cable with different winding parameters. In addition, optimal winding parameters, which provide valuable guidance for designing a high-performance single-layer CORC cable, were proposed.

In this paper, CuCr–Zr alloys prepared by vacuum melting with adding La and Ni elementswere heat-treated and aged, followed by plastic deformation using low-energy cyclic impact tests, to simultaneously improve their mechanical and electrical properties. Results showed that the grain size of the casted Cu–Cr–Zr alloys was significantly reduced after the solid-solution aging and plastic deformation process. There were a lot of dispersed Cr and Cu5Zr precipitates formed in the alloys, and the numbers of dislocations were significantly increased. Accordingly, the hardness was increased from 78 to 232 HV, and the tensile strength was increased from 225 to 691 MPa. Electrical conductivity has not been significantly affected after these processes. The enhancement of overall performance is mainly attributed to the combined effects of solid-solution hardening, fine grain hardening, and precipitation/dislocation strengthening.

In order to clarify the effects of the proportion of raw powders, heating temperature and holding time on the purity and properties of MAX phase Ti3AlC2, powder mixtures of Ti, Al and C powder with different ratio were prepared by planetary ball mill and heated under different conditions by spark plasma sintering. The microstructures and phase structures of the as-synthesized samples were characterized, the correlation between the mechanical properties and microstructure and fracture mechanism were investigated systematically. The results show that with the proportion of raw powders Ti:Al:C = 3:1.2:2, the sample heated at 1300 °C for 60 min has the highest purity 97.23 wt% of MAX phase. It has a compact and uniform lath-like structure with the length-thickness ratios of 3–5 and excellent comprehensive mechanical properties: the Vickers hardness, bending strength and fracture toughness are 5.26 GPa, 500 MPa and 7.35 MPa∙m1/2, respectively. The experimental results show that among the three factors, the proportion of raw powders has the greatest influence on purity of Ti3AlC2 phase, followed by heating temperature and holding time. The fracture morphologies of the tested samples demonstrate that under the action of external force, extrusion and kink occurred in the layered structures of Ti3AlC2 phase. These two forms of energy dissipation lead to the bending strength and fracture toughness of Ti3AlC2 are higher than that of traditional ceramics.

Asymmetric capacitor like the so-called lifter can fly up from the ground. Some common characteristics exist in the asymmetric capacitor: high-voltage, capacitor, lift force. What are the accurate quantitative relations among them and how can we figure the lift force out? It’s a thorny problem so far. In this article, we attempt to establish a model that can match the actual experimental data and theory derivation result. After checking, the calculation result is verified to be correct.

Owing to their unique physicochemical properties, metal-organic frameworks (MOFs) are a kind of promising material for electrocatalysis. However, many reports focus on the use of MOFs as precursors to produce efficient electrocatalysts by pyrolysis. The use of pristine MOFs with well-defined structures as efficient electrocatalysts directly is still a challenging problem. Herein, S,N-containing MnII[(Tdc)(4,4'-Bpy)]n with different morphologies have been obtained by using MnII, thiophene-2,5-dicarboxylate (Tdc) and 4,4'-bipyridine (4,4'-Bpy) as raw materials via hydrothermal synthesis. Furthermore, the influences of different hydrothermal reaction times (0, 2 and 4 h) and anions (SO42-, Cl-, NO3- and CH3COO-) on the morphologies, compositions and ORR activity of the resultant Mn-MOFs are also investigated at length. The results indicate that only the reaction of MnSO4 with Tdc and 4,4'-Bpy for 4 h can form relatively uniform one-dimensional (1D) MOF nanorods. The 1D nanorods combine the favorable features towards the oxygen reduction reaction (ORR), such as a high surface area and efficient 1D electron/mass transport capability. Therefore, the MnII[(Tdc)(4,4'-Bpy)]n nanorods display the highest ORR activity with an onset potential of 0.98 V and a half-wave potential of 0.78 V vs. RHE (reversible hydrogen electrode), which is even comparable to that of Pt/C. In addition, the MnII[(Tdc)(4,4'-Bpy)]n nanorods exhibit higher stability, methanol resistance and ORR selectivity than Pt/C. The present study illustrates an efficient fabrication strategy for highly efficient 1D MOF nanorods for energy storage and conversion applications.

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.

In order to solve problems of significant interfacial reactions and agglomeration in graphene reinforced W Cu composites, powders of copper coated graphene (Cu@Gr) were pre-mechanically mixed with tungsten and copper powders, and then graphene doped W Cu composites were sintered using two different methods, e.g., spark plasma sintering (SPS) and infiltration sintering. Microstructural analysis showed that the doped Cu@Gr powder can effectively inhibit the interfacial reaction between graphene and tungsten, prevent the segregation of graphene, and evenly distribute the copper in the binder phase. When the mixed concentration of Cu@Gr was 0.45 wt%, uniform distributions of W phase and Cu phase were obtained in the composite, and the mechanical properties and conductivity of this composite achieved their best results. When the doping content was further increased to 0.8%, WC phase was found in all alloys, thus resulting in poor mechanical and physical properties. Comparing the microstructures produced using these two methods, the composites prepared using the infiltration sintering method showed network distribution of copper phase and segregation of copper, whereas the composites prepared using the SPS method showed network skeleton phase of tungsten. Although the SPS process was performed in a much shorter time, the mechanical properties of the composites sintered using the SPS process did not show much differences with those sintered using the infiltration sintering method.

REBCO coated conductor has been regarded as one of the most viable high-temperature superconductor (HTS) options for next-generation high field magnets, mainly owing to its large in-field current carrying capacity and higher mechanical strength. To explore REBCO coil technology, a small-scale REBCO coil was designed, fabricated and tested. The REBCO coil has a winding inner diameter of 15 mm, outer diameter of 29 mm and length of 38 mm using layer-wound and no-insulation technology. The REBCO coil was tested in a 31.5 T background field, leading to a high field of 32.5 T. The no-insulation behaviors of the REBCO coil, including the charging delay and magnet constant, were investigated at 77 K and 4.2 K respectively. With the magnetic load from the high fields, we found the REBCO coil was mechanically damaged after the experiments, being two major patterns: peeling and bucking.

Ideology and power, the vital concerns of critical lexicography, are aspects of a dictionary that a lexicographer and a discerning dictionary user have to encounter in any serious lexicographical enterprise (Kachru 1995); however, critical lexicography as a theme did not receive much attention until Kachru and Kahane (1995). This term later appeared in Hornscheidt (2011) and Moon (2014). However, to date there has not been any systematic theoretical exemplification of what critical lexicography is and how critical lexicographical research is done. Additionally, the scope and function of critical lexicography is relatively limited when we consider the global context, since it fails to take into account theoretical and methodological inspirations from other disciplines such as Critical Discourse Studies and/or Postcolonial Studies, which would make it more theoretically robust and analytically explanatory. With this gap in mind, this paper proposes a discourse approach to Critical Lexicography, termed Critical Lexicographical Discourse Studies (CLDS), as a response to the call for lexicographers’ ‘social accountability’. Specifically, the article puts forward a definition of CLDS and its key concepts, denotes its ontological, epistemological and methodological orientations, delineates its principles, proposes a tentative analytic framework and demonstrates a simplified case study. The article argues that a discourse approach to critical lexicography opens up space to understand different meaning-making practices and contestation in lexicography. In doing so, this article contributes to the development of international (English) lexicography and the language(s) it represents.

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.