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We focus on the following problem: Given a collection of unlabeled facial images, group them into the individual identities where the number of subjects is not known. To this end, a Portable clustering algorithm based on Compact Neighbors called PCN is proposed. (1) Benefiting from the compact neighbor, the local density of each sample can be determined automatically and only one user-specified parameter, the number of nearest neighbors k , is involved in our model. (2) More importantly, the performance of PCN is not sensitive to the number of nearest neighbors. Therefore this parameter is relatively easy to determine in practical applications. (3) The computational overhead of PCN is O (n k (k 2 + l o g (n k))) that is nearly linear with respect to the number of samples, which means it is easily scalable to large-scale problems. In order to verify the effectiveness of PCN on the face clustering problem, extensive experiments based on a two-stage framework (extracting features using a deep model and performing clustering in the feature space) have been conducted on 16 middle- and 5 large-scale benchmark datasets. The experimental results have shown the efficiency and effectiveness of the proposed algorithm, compared with state-of-the-art methods. [code] • The computational overhead is nearly linear with respect to the number of samples. • Only one user-specified parameter is involved, the number of nearest neighbors. • The performance of the proposed model is not sensitive to the hyper-parameter. • Experimental results verified the efficiency and effectiveness of our model. [ABSTRACT FROM AUTHOR]

The high-temperature oxidation behaviors of laser powder bed fusion (LPBF)-fabricated AlCoCrCuFeNi high-entropy alloy (HEA) with and without laser shock peening (LSP) were investigated over different exposure durations and temperatures. Results revealed that LSP converted the surface stress from tensile to compressive, while also inducing grain refinement and high-density dislocations. Under high temperatures, the coupled effects of grain refinement and compressive residual stress resulted in the formation of dense protective oxidation scales, which inhibited the inward diffusion of oxygen. LSP improved the high-temperature oxidation resistance of LPBF-fabricated AlCoCrCuFeNi HEA, and the enhanced oxidation-resistance mechanisms were discussed. • LSP modifies the surface microstructure of LPBF-fabricated HEA. • High-temperature oxidation behaviors of HEA with and without LSP are studied. • LSP improves the high-temperature oxidation resistance of LPBF-fabricated HEA. • The enhanced oxidation-resistance mechanisms induced by LSP are summarized. [ABSTRACT FROM AUTHOR]

Inspired by the structure of corn, a NiFe Prussian blue analogue nanocages decorated magnesium hydroxide composite was synthesized for the first time using magnesium hydroxide rods (RMH) as the "corn cob", a Prussian blue analogue (PBA) as the "corn kernels" and polydopamine (PDA) as the membrane linking RMH and PBA. Subsequently, the RMH@PDA@PBA composite was introduced into epoxy resin (EP) to improve its fire retardancy and mechanical properties. The composition, structure and morphology of the RMH@PDA@PBA-incorporated EP composite were investigated. The tensile strength of EP with 3 wt.% RMH@PDA@PBA reached 41.77 MPa, which is higher than that of neat EP (40.51 MPa). The fire-retardant assessments illustrated that the limiting oxygen index and vertical burning tests (UL-94) of EP composite with 3 wt.% RMH@PDA@PBA progressed to 32.3% and the V-0 level as compared to those of virgin EP (24.4% and no rating). In addition, as compared to virgin EP, the peak heat release rate, peak smoke production rate, total heat release at 200 s and total smoke production at 200 s of EP/3RMH@PDA@PBA decreased by 43.1%, 50.0%, 43.9% and 56.3%, respectively. The investigation of the underlying mechanism revealed that the flame retardancy and smoke suppression of EP/3RMH@PDA@PBA were attributed to the endothermic decomposition of RMH, "gauze barrier" mechanism of MgO/FeO, catalytic charring effect of Fe derivatives (MgO/FeO, FeNi 3 , Fe 5 C 2 , Fe 2 N, etc.) and free radical scavenging effect of PBA@Fe[Ⅲ]. Thus, this study on bio-inspired hierarchical nanostructures paves a new pathway for the efficient production of fire-safe polymers. [Display omitted] • A novel low-cost RMH@PDA@PBA with corn structure was first prepared. • The RMH@PDA@PBA significantly improves the fire safety of epoxy resin. • 3 wt.% RMH@PDA@PBA endowed epoxy resin with UL-94 V-0 and reduced smoke production. • The addition of RMH@PDA@PBA enhanced the mechanical properties of epoxy resin. [ABSTRACT FROM AUTHOR]

• The MRT-LB model with Beam-Warming scheme is developed based on the potential form of hydrodynamic equations. • The present MRT-LBM model can significantly reduce the magnitude of spurious currents. In this work, a multiple-relaxation-time (MRT) lattice Boltzmann (LB) equation model with Beam-Warming (B-W) scheme is proposed to simulate a multi-phase fluid system with Peng-Robinson (P-R) equation of state (EOS). The mathematical model of the multi-phase fluid flow is derived based on the NVT-based framework, where the Helmholtz free energy of P-R EOS is introduced. The nonideal force in the multi-phase flow is directly computed from the free energy in order to obtain a more compact formulation of hydrodynamic equations, which is termed as potential form. The MRT-LB model is developed based on the potential form of hydrodynamic equations, which can eliminate spurious currents effectively. In addition, to capture the tiny nonconvex perturbation from the linear trend of P-R model precisely, the B-W scheme is utilized in the present MRT-LB model, which gives rise to an adjustable Courant-Friedrichs-Lewy (CFL) number. Also, the second order accuracy can be naturally achieved by this scheme without any other requirements and numerical boundary conditions. In the numerical experiments, a realistic hydrocarbon component (isobutane) in three dimensional space is simulated by the proposed MRT-LB model. Numerical results show that the magnitude of spurious currents can be significantly reduced by the present MRT-LB model. In addition, our numerical predictions of surface tension agree well with the experimental data, which verify the effectiveness of the proposed MRT-LB model. [ABSTRACT FROM AUTHOR]

Due to low activity or long mineralization time, traditional mineral agents for self-healing concrete generally need a long time to achieve a desired repair efficiency. Inspired by epoxy resin AB glue which can consolidate in a short time when mixing the two components together, a novel type of fast-responsive capsules based on two soluble components was designed for self-healing concrete. Component A (sodium carbonate) and component B (calcium acetate) were encapsulated in two different groups of capsules, respectively, coated with three layers consisting of epoxy resin and fine sands to achieve superior waterproof and alkali resistance properties. After rupture of the capsules, the rapid response with respect to core material dissolution and precipitation can be realized in presence of water, by which the cracks below 200 μm can be healed in 3 days. Super absorbent resin (SAP) embedded in the capsules could expand in contact with water, and further improve the self-healing efficiency of the capsules by blocking the crack. [ABSTRACT FROM AUTHOR]

Based on the interesting Janus-type all- cis 1,2,3,4,5,6-hexafluorocyclohexane (1) molecule, a novel type of excess electron compounds MF- 1 -MH (MF = Li, Na and K, MH = Zn, Cd and Hg) were designed theoretically. The geometric structures, electronic structures and nonlinear optical properties of MF- 1 -MH compounds were studied by density functional theory. Our results show that in Li- 1 -MH, the obvious charge transfer between Li and MH can be observed while in Na/K- 1 -MH, the charge transfer between Na/K and MH is negligible. Particularly, the MF- 1 -MH exhibit remarkable nonlinear optical (NLO) response and the first hyperpolarizability of the K- 1 -Zn almost achieve 1.0 × 106 au. We hope this work will further enrich the family of excess electron compounds, so that more experimental interests and efforts can be attracted to propose and synthesize new excellent NLO materials. Table of contents synopsis: A novel type of NLO compounds which were designed by using transition metal atoms (Zn, Cd and Hg) and alkali metal atoms (Li, Na and K). [Display omitted] • A novel type of excess electron compounds using Group 12 elements (Zn, Cd and Hg) with large nonlinear optical responses is proposed. • Using the electron localization function (ELF), localized orbital locator (LOL) and Independent gradient model (IGM) methods to study the electronic structures of proposed compounds. • The low transition energies can lead to high nonlinear optical responses. [ABSTRACT FROM AUTHOR]

SUMO-specific protease 3 (SENP3) participates in the removal of SUMOylation and maintains the balance of the SUMO system, which ensures normal functioning of substrates and cellular activities. In the present study, we found that SENP3 expression was significantly reduced in ox-LDL-stimulated macrophages. SENP3 overexpression suppressed and SENP3 knockdown promoted macrophage foam cell formation. Moreover, SENP3 inhibited cholesterol uptake, CD36 expression, and NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome activation in ox-LDL-stimulated macrophages. Ox-LDL-stimulated NLRP3 SUMOylation was reduced by SENP3. Blocking NLRP3 SUMOylation inhibited foam cell formation and NLRP3 inflammasome activation. Thus, this study revealed that SENP3 inhibits macrophage foam cell formation by deSUMOylating NLRP3 and regulating NLRP3 inflammasome activation, which may provide a potentially innovative approach to treatment of atherosclerosis. • SENP3 inhibits ox-LDL-induced macrophage foam cell formation. • Expression level of SENP3 is downregulated in macrophage foam cells. • SENP3 suppresses CD36 expression and cholesterol uptake in ox-LDL-stimulated macrophages. • SENP3 deSUMOylates NLRP3 to inhibit NLRP3 inflammasome activation in ox-LDL-stimulated macrophages. [ABSTRACT FROM AUTHOR]

• A kind of biochar-modified water purifying pervious concrete was analyzed. • The purification effects of different biochar contents were compared. • The water purification mechanism of pervious concrete was investigated. • The optimized content of biochar was recommended. Pervious concrete, a kind of porous material, is commonly used in permeable pavement and ecological slope protection. Biochar has the characteristics of absorbing pollutants and improving the performance of concrete. Therefore, the purification performance of different contents of biochar-modified pervious concrete on sewage was studied in this work. The experimental results show that the pervious concrete has obvious purification performance on sewage and adding biochar to the pervious concrete can further improve the removal capacity of total nitrogen (TN) and total phosphorus (TP). The removal efficiency of TN and TP increased by 34.1% and 47.3%, respectively, compared with the specimen without biochar. The water purification mechanism of pervious concrete is mainly mechanical retention adsorption and microbial degradation. With increasing biochar content, the adsorption increased, whereas the porosity of the specimen decreased, which was not conducive to microorganism growth. Therefore, the pervious concrete block with moderate biochar content had the best water purification performance. It is recommended to use pervious concrete with a biochar content range of 15 kg/m3-20 kg/m3. [ABSTRACT FROM AUTHOR]