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Purpose: Nasopharyngeal carcinoma (NPC) has characteristics of high invasion and early metastasis. Most NPC patients present with locoregionally advanced illness when first diagnosed. Therefore, it is urgent to discover NPC biomarkers. Fibroblast growth Factor 19 (FGF19) plays a role in various physiological or pathological processes, including cancer. In this research, we discovered the importance of FGF19 in NPC, and clarified its role in tumour angiogenesis. Methods: Western blotting, immunohistochemistry and ELISA were used to investigate FGF19 expression in NPC. Then we took CCK8, colony formation, Transwell and wound healing assays to identify the influence of FGF19 on NPC malignant behaviours. The proliferative and metastatic capacity of FGF19 were evaluated in nude mice and zebrafish. The role of FGF19 in angiogenesis was investigated by tube formation and Matrigel plug angiogenesis assays. We then evaluated the variation in Annexin A2(ANXA2) levels with the treatment of FGF19. Lastly, co-immunoprecipitation and ubiquitination assays were performed to identify the mechanisms involved. Results: FGF19 levels were elevated in tissues and serum of NPC patients and were associated with poor clinical stages. High expression of FGF19 promoted NPC malignant behaviours. In particular, FGF19 expression was correlated with microvessel density in tissues and NPC-derived FGF19 could accelerate angiogenesis in vitro and in vivo. Mechanistically, FGF19 influenced ANXA2 expression to promote angiogenesis. Moreover, tripartite motif-containing 21(TRIM21) interacted with ANXA2 and was responsible for ANXA2 ubiquitination. Conclusion: FGF19 promoted NPC angiogenesis by inhibiting TRIM21-mediated ANXA2 ubiquitination. It may serve as a noninvasive biomarker for NPC and provides new insights for therapy. [ABSTRACT FROM AUTHOR]

Papillary thyroid carcinoma (PTC) has a relatively good prognosis, yet there are some invasive PTC cases with worse clinicopathological features and poor outcome. Cancer-associated fibroblasts (CAFs) play an important role in cancer invasion and metastasis. This study aimed to investigate the expression of marker proteins of CAFs in PTC and their correlations with clinicopathological features through immunohistochemistry. The medical records of 125 PTC patients were reviewed in this study, whose specimens were retrieved for immunohistochemistry. Four CAFs marker proteins, FAP fibroblast activated protein (FAP), α-smooth muscle actin (α-SMA), Vimentin and platelet-derived growth factor receptor-α(PDGFR-α), were stained and scored. Then, statistical analyses were performed. The immunoreactivity scores of FAP and α-SMA correlated with tumor size, BRAF mutation, extrathyroidal, invasion, pathological subtype, lymph node metastasis and ATA risk stratification. Moreover, binary logistic regression analysis and receiver operating characteristic curves showed that high FAP and α-SMA immunoreactivity scores were risk factors for extrathyroidal invasion, BRAF mutation, multi-focality and lymph node metastasis (especially N1b) with good sensitivity and accuracy in prediction. A better performance was found in FAP than α-SMA. Strong expressions of CAFs were risk factors for worse thyroid cancer clinicopathological features. FAP was the better CAFs marker for PTC. [ABSTRACT FROM AUTHOR]

Symmetry plays a key role in classifying topological phases. Recent theory shows that in the presence of gauge fields, the algebraic structure of crystalline symmetries needs to be projectively represented, which brings extra chance for topological physics. Here, we report a concrete acoustic realization of mirror Chern insulators by exploiting the concept of projective symmetry. Specifically, we introduce a simple but universal recipe for constructing projective mirror symmetry, and conceive a minimal model for achieving the projective symmetry-enriched mirror Chern insulators. Based on our selective-excitation measurements, we demonstrate unambiguously the projective mirror eigenvalue-locked topological nature of the bulk states and associated chiral edge states. We extract the non-abelian Berry curvature and identify the mirror Chern number directly, providing experimental evidence for this exotic topological phase. All experimental results agree well with the theoretical predictions. Our findings give insights into topological systems equipped with gauge fields. A recurring theme in physics has been the discovery of distinctive phases of matter. Here, the authors propose a general recipe for constructing projective mirror symmetry and report an experimental realization of mirror Chern insulators in spinless systems. [ABSTRACT FROM AUTHOR]

Integrated phononics plays an important role in both fundamental physics and technology. Despite great efforts, it remains a challenge to break time-reversal symmetry to achieve topological phases and non-reciprocal devices. Piezomagnetic materials offer an intriguing opportunity as they break time-reversal symmetry intrinsically, without the need for an external magnetic field or an active driving field. Moreover, they are antiferromagnetic, and possibly compatible with superconducting components. Here, we develop a theoretical framework that combines linear elasticity with Maxwell's equations via piezoelectricity and/or piezomagnetism beyond the commonly adopted quasi-static approximation. Our theory predicts and numerically demonstrates phononic Chern insulators based on piezomagnetism. We further show that the topological phase and chiral edge states in this system can be controlled by the charge doping. Our results exploit a general duality relation between piezoelectric and piezomagnetic systems, which can potentially be generalized to other composite metamaterial systems. Understanding and controlling symmetry in nature is of paramount importance. In this work, the authors reveal an unexpected effect of the general duality relation between piezoelectricity and piezomagnetism on their symmetries, enabling novel phononic Chern insulators. [ABSTRACT FROM AUTHOR]

The work describes experiments and models related to auxetic (negative Poisson's ratio) foams subjected to low-frequency and variable amplitude 3-point bending loading. A custom 3-point bending vibration test rig is designed and used to perform the dynamic test of auxetic PU foam beams within low-frequency range (1–20 Hz) and 5 different displacement amplitudes. The auxetic foams tested in this work are manufactured using a simplified and relatively low-cost uniaxially thermoforming compression technique, which leads to the production of foams with transverse isotropic characteristics. Auxetic foam beam samples with two different cutting orientations and different thermoforming compression ratios rc (20–80%) are tested and compared, also with the use of theoretical Euler–Bernoulli-based and finite element models. The dynamic modulus of the foams increases with rc, ranging between 0.5 and 5 MPa, while the dynamic loss factor is marginally affected by the compression ratio, with overall values between 0.2 and 0.3. The auxetic PU foam has a noticeable amplitude-dependent stiffness and loss factors, while the dynamic modulus increases but slightly decreases with the frequency. The dynamic modulus is also 20–40% larger than the quasi-static one, while the dynamic and static loss factors are quite close. A modified Bouc–Wen model is also further developed to capture the amplitude and frequency-dependent properties of the conventional and auxetic foams with different volumetric compression ratios. The model shows a good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

With the intensity of resource scarcities and environmental problems, the disposal and recovery of spent lithium-ion batteries, especially recovery of valuable metals, becomes vital. In this work, a method of co-extracting nickel, cobalt, manganese and being separated from lithium by single-stage solvent extraction is proposed. The extraction and separation process of D2EHPA was studied. The effects of extractant concentration, saponification percentage, extraction time and O:A on the extraction efficiency of D2EHPA were systematically studied. Nearly 100% manganese, 94% cobalt and about 90% nickel were co-extracted and separated from lithium using D2EHPA in kerosene by single-stage extraction. The maximum value of separation factors (βNi/Li, βCo/Li and βMn/Li) was 13.03, 23.42 and 1904.24. The mathematical model of extraction of four ions was developed by combination of Levenberg-Marquardt method and Universal Global Optimization method. The proposed extraction model accurately fits the experimental data and helps to predict the extraction efficiency of each metal under the corresponding conditions. [ABSTRACT FROM AUTHOR]

Microorganism invasion is still a severe threat for wound healing, which usually induces severe complications and cannot be eradicated completely. Thus, a biodegradable nanomaterial for guarding against bacteria-associated wound infection and accelerating wound healing is of vital importance. Here, black phosphorus nanosheets (BPs) were successfully decorated with cationic carbon dots (CDs) through an in situ growth strategy. The BPs@CDs exhibit photon-responsiveness and contact-responsiveness as an antibacterial agent, which shorten wound healing time. Moreover, the BPs@CDs show available photothermal and photodynamic therapy via exploring their photothermal properties and the ability of singlet-oxygen (1O2) production. Astonishingly, the BPs@CDs could possess antibacterial activity even without laser illumination due to an electrostatic attraction between bacteria and cationic CDs on the surface of BPs. This chemical therapy causes the antibacterial process to occur more accurately and for a faster 1O2 release to kill bacteria than in a normal process. Importantly, BPs@CDs display outstanding cytocompatibility and hemocompatibility. In vitro and in vivo investigations demonstrate that the BPs@CDs have enhanced antibacterial effect and can significantly accelerate skin tissue regeneration and wound closure. Given their antibacterial triple-combination therapy and excellent physicochemical properties, the broad application of BPs@CDs in bacteria-associated wound management is anticipated. [ABSTRACT FROM AUTHOR]

The properties of van der Waals (vdW) materials often vary dramatically with the atomic stacking order between layers, but this order can be difficult to control. Trilayer graphene (TLG) stacks in either a semimetallic ABA or a semiconducting ABC configuration with a gate-tunable band gap, but the latter has only been produced by exfoliation. Here we present a chemical vapor deposition approach to TLG growth that yields greatly enhanced fraction and size of ABC domains. The key insight is that substrate curvature can stabilize ABC domains. Controllable ABC yields ~59% were achieved by tailoring substrate curvature levels. ABC fractions remained high after transfer to device substrates, as confirmed by transport measurements revealing the expected tunable ABC band gap. Substrate topography engineering provides a path to large-scale synthesis of epitaxial ABC-TLG and other vdW materials. The semiconducting ABC configuration of trilayer graphene is more challenging to grow on large scales than its semimetallic ABA counterpart. Here, an approach to trilayer growth via chemical vapor deposition is presented that utilizes substrate curvature to yield enhanced fraction and size of ABC domains. [ABSTRACT FROM AUTHOR]

This paper describes the influence on the compressive and dissipative behavior of entangled metallic wire material (EMWM) samples provided by their size and mutual connectivity. The mechanical properties of EMWM specimens with different thicknesses are obtained from quasi-static compressive and cyclic loading. The behavior of the stress-strain curves, tangent modulus, and loss factor are strongly dependent on the thickness of the samples. The analysis from samples connected in different layouts shows that apart from the global thickness, size scale effects and contact interface also play important roles in controlling the behavior of EMWM systems. The importance of the sample size and its connectivity with adjacent different layers are defined by the unique microstructure and contact properties of the wires near the specimen boundary layer. The boundary layer produces different mechanical behaviors and a distinct structural configuration compared to the EMWM bulk solid. These peculiar characteristics are confirmed by microstructural and qualitative observations obtained from computed tomography scanning. The results and analysis presented in this work are relevant to designing EMWM material systems with adaptive performance under different loading and geometric constraints. [ABSTRACT FROM AUTHOR]

This paper describes an efficient method to predict the nonlinear steady-state response of a complex structure with multi-scattered friction contacts. The contact friction force is equivalent to additional stiffness and damping based on optimal approximation theory, and as a consequence, the computation is simplified greatly by the linearization for a nonlinear system. In order to obtain accurate pressure distribution on the contact interfaces, the dynamic contact normal pressure is obtained by the equivalent static analysis which is validated for most engineering cases. Considering the complex procedure to determine the transformation between two different contact states, the differential forms of friction force are given to solve the tangential force accurately under the complex movement of interfaces. The approaches developed in this paper are particularly suitable to solve the dynamic response of large-scale structures with local contact nonlinearities. The entire procedure to calculate the steady-state response of a finite element model with a large number of degrees of freedom is demonstrated taking the blades with underplatform dampers as an example. The method is proved to be accurate and efficient; in particular, it does not suffer convergence problem in the allowable range of precision error, which exhibits remarkable potential engineering application values. [ABSTRACT FROM AUTHOR]

Foamy virus (FV) establishes persistent infection in the host without causing apparent disease. Besides the transactivator Tas protein, another auxiliary protein-Bet-has been reported in prototype foamy virus, equine foamy virus, and feline foamy virus. Here, we found the putative bbet gene in clone C74 from a cDNA library of bovine foamy virus strain 3026 (BFV3026) by comparison of gene localization, composition, and splicing features with other known bet genes. Subsequently, BBet protein was detected in BFV3026-infected cells by Western blot and immunofluorescence analyses. Analysis of the BBet mutant infectious clone (pBS-BFVdelBBet) revealed that BBet could inhibit BFV3026 replication. Consistent with this result, overexpression of BBet in Cf2Th cells reduced BFV replication by approximately threefold. Furthermore, virus replication levels similarly were reduced by approximately threefold in pBS-BFV-transfected and BFV3026-infected Cf2Th cells stably expressing BBet compared with control cells. After three passages, BFV3026 replicated more slowly in BBet-expressing cells. This study implicates BBet as a negative regulator of BFV replication and provides a resource for future studies on the function of this protein in the virus lifecycle. [ABSTRACT FROM AUTHOR]