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It is well known that earthquakes are one of the most catastrophic geological disasters. In recent years, the use of metasurfaces to suppress the propagation of seismic surface waves to protect surface buildings has received extensive attention. However, most of the previous research works are on linear metasurfaces and the effect of vertical resonators. In this work, we propose a nonlinear metasurface, which consists of a linear elastic semi-infinite space with vertical nonlinear and horizontal linear resonators attached to its top surface. Our study shows that the interaction between the dynamics of the resonators and the waves of the semi-infinite space creates a hybrid Rayleigh wave propagating along the surface. First, the dispersion of the hybrid Rayleigh wave is derived analytically. Then, numerical calculations are conducted and the effect of the coupling of the vertical and horizontal resonators on the dispersion is discussed. Afterward, a finite-element simulation is performed to verify the analytical predictions. The results demonstrate that an ultra-wide bandgap for the hybrid Rayleigh wave can be achieved by the designed nonlinear metasurface. This work may help promote the application of metasurfaces in the field of earthquake protection.

The study aimed to improve the qualified rate of hand hygiene and reduce the incidence of peritonitis in peritoneal dialysis (PD) patients.A hand hygiene questionnaire was distributed to patients during home visits and outpatient visits in 2015 and 2020. Hand-washing practices were evaluated by collecting cultures from the hands of patients after hand washing, evaluating their household environment, and recording the antimicrobial resistance of pathogenic bacteria.Compared to patients in 2015, patients in 2020 had fewer errors in hand washing (p 0.05), but the rate of qualification after hand washing was lower (p 0.01). Furthermore, patients who used hand disinfectants after washing had a higher qualified rate. Coagulase-negative staphylococcus (CNS) was the most common isolated bacteria. From 2015 to 2020, the annual incidence of CNS PD peritonitis did not decrease, while the proportion of methicillin-resistant CNS decreased.The use of hand disinfectants after standard hand washing may help reduce the incidence of peritonitis in PD patients.

Hepatocellular carcinoma (HCC) is an inflammation-associated cancer. However, the lipid pro-inflammatory mediators have only been seldom investigated in HCC pathogenesis. Cylindromatosis (CYLD) attenuation is involved in hepatocarcinogenesis. Here, we aimed to evaluate the significance of hepatic lipid pro-inflammatory metabolites of arachidonate-affected CYLD expression via the 5-lipoxygenase (5-LO) pathway. Resection liver tissues from HCC patients or donors were evaluated for the correlation of 5-LO/cysteinyl leukotrienes (CysLTs) signaling to the expression of CYLD. The impact of functional components in 5-LO/CysLTs cascade on survival of HCC patients was subsequently assessed. Both livers from canines, a preponderant animal for cancer research, and genetic-modified human HCC cells treated with hepatocarcinogen aristolochic acid I (AAI) were further used to reveal the possible relevance between 5-LO pathway activation and CYLD suppression. Five-LO-activating protein (FLAP), an essential partner of 5-LO, was significantly overexpressed and was parallel to CYLD depression, CD34 neovascular localization, and high Ki-67 expression in the resection tissues from HCC patients. Importantly, high hepatic FLAP transcription markedly shortened the median survival time of HCC patients after surgical resection. In the livers of AAI-treated canines, FLAP overexpression was parallel to enhanced CysLTs contents and the simultaneous attenuation of CYLD. Moreover, knock-in FLAP significantly diminished the expression of CYLD in AAI-treated human HCC cells. In summary, the hepatic FLAP/CysLTs axis is a crucial suppressor of CYLD in HCC pathogenesis, which highlights a novel mechanism in hepatocarcinogenesis and progression. FLAP therefore can be explored for the early HCC detection and a target of anti-HCC therapy.

The propagation of transition waves in multi-stable mechanical systems can be effectively harnessed in various fields, such as mechanical signal communication, mechanical diodes, and energy absorption. In this work, the propagation of transition waves in a one-dimensional (1D) bistable mass-spring chain is systematically studied. The underlying physical mechanism for the formation and propagation of transition waves is clarified, and the influences of some crucial factors, such as the pumped momentum, stiffness of the connecting springs, viscous damping, number of masses, and asymmetry of the double-well potential, on the propagation of transition waves are discussed in detail. As a result, the parameter space for achieving the robust propagation of transition waves through the whole chain is presented. This study is expected to be beneficial for the control of transition waves and design of novel devices used for mechanical signal transmission.

Background Most studies had used sufentanil and ropivacaine for intrathecal anesthesia in adults or children，but few studies had used sufentanil and ropivacaine for peripheral nerve block, especially in children. Brachial plexus block was one of the most commonly used nerve block methods in children. Therefore, the purpose of this study was to investigate whether 0.1µg/kg sufentanil combined with 0.25% ropivacaine can improve analgesia and prolong analgesia in children compared with ropivacaine alone.Methods 80 children, ASA I, aged 5-10 years old, undergoing upper limb surgery, were randomly divided into two groups: RS group(0.25% ropivacaine combined with 0.1µg/kg sufentanil) and R group (0.25% ropivacaine alone). The dosage of 0.25% ropivacaine administered in each group was 0.5ml/kg. After general anesthesia, all children underwent ultrasound-guided brachial plexus block and were performed by the same experienced anesthetist. The primary outcome measures were the FLACC score at 2, 4, and 6 h after surgery and the duration of analgesia in each group. Secondary outcome measures were the changes in vital signs during surgery in each group, the incidence of postoperative agitation, the postoperative awake time and the duration of stay in PACU. Results The FLACC scores at 2, 4 and 6 hours after surgery and the duration of analgesia showed no statistically significant difference. There were no statistically significant differences in the changes in vital signs during surgery in each group. The incidence of postoperative agitation was significantly lower in RS group than R group(20% vs 45%, PConclusion Compared with 0.25% ropivacaine alone, 0.1µg/kg sufentanil combined with 0.25% ropivacaine for pediatric brachial plexus block did not improve analgesia and prolong analgesia, but reduced postoperative agitation in the children.Trial RegistrationRegistration of Chinese Clinical Trial Registry(Date:19/04/2020, Number:ChiCTR2000032071).

Type 2 diabetes (T2D) patients with SARS-CoV-2 infection hospitalized develop an acute cardiovascular syndrome. It is urgent to elucidate underlying mechanisms associated with the acute cardiac injury in T2D hearts. We performed bioinformatic analysis on the expression profiles of public datasets to identify the pathogenic and prognostic genes in T2D hearts. Cardiac RNA-sequencing datasets from db/db or BKS mice (GSE161931) were updated to NCBI-Gene Expression Omnibus (NCBI-GEO), and used for the transcriptomics analyses with public datasets from NCBI-GEO of autopsy heart specimens with COVID-19 (5/6 with T2D, GSE150316), or dead healthy persons (GSE133054). Differentially expressed genes (DEGs) and overlapping homologous DEGs among the three datasets were identified using DESeq2. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes analyses were conducted for event enrichment through clusterProfile. The protein-protein interaction (PPI) network of DEGs was established and visualized by Cytoscape. The transcriptions and functions of crucial genes were further validated in db/db hearts. In total, 542 up-regulated and 485 down-regulated DEGs in mice, and 811 up-regulated and 1399 down-regulated DEGs in human were identified, respectively. There were 74 overlapping homologous DEGs among all datasets. Mitochondria inner membrane and serine-type endopeptidase activity were further identified as the top-10 GO events for overlapping DEGs. Cardiac CAPNS1 (calpain small subunit 1) was the unique crucial gene shared by both enriched events. Its transcriptional level significantly increased in T2D mice, but surprisingly decreased in T2D patients with SARS-CoV-2 infection. PPI network was constructed with 30 interactions in overlapping DEGs, including CAPNS1. The substrates Junctophilin2 (Jp2), Tnni3, and Mybpc3 in cardiac calpain/CAPNS1 pathway showed less transcriptional change, although Capns1 increased in transcription in db/db mice. Instead, cytoplasmic JP2 significantly reduced and its hydrolyzed product JP2NT exhibited nuclear translocation in myocardium. This study suggests CAPNS1 is a crucial gene in T2D hearts. Its transcriptional upregulation leads to calpain/CAPNS1-associated JP2 hydrolysis and JP2NT nuclear translocation. Therefore, attenuated cardiac CAPNS1 transcription in T2D patients with SARS-CoV-2 infection highlights a novel target in adverse prognostics and comprehensive therapy. CAPNS1 can also be explored for the molecular signaling involving the onset, progression and prognostic in T2D patients with SARS-CoV-2 infection.

In this programmatic paper, we approach #wordswewear, referring to the wide range of linguistic inscriptions on clothing and accessories, as part of the embodied, mobile semiotic landscape of the c...

In this work, Ni49.4Ti50.6 Belleville washers are prepared by metal injection moulding (MIM). The martensitic transition temperatures and service performance of washers were investigated. The therm...

This study investigates the sintering neck growth behavior of pure titanium powder with different oxygen contents. The growth rate of the sintering neck gradually decreased as the oxygen content increased from 0.06 wt% to 0.50 wt%. At the same time, it was observed that the oxygen in the sintering neck spread to the low oxygen region as the size of the neck increased. A theoretical analysis indicated that surface diffusion is the dominant diffusion mechanism. However, under the hindrance of oxygen in the matrix, both surface diffusion and grain boundary diffusion slow down. Calculating the increase in the self-diffusion activation energy of Ti atoms indicated that oxygen was more resistant to surface diffusion. Predictably, grain boundary diffusion will become the dominant diffusion mechanism in the initial stage of sintering when the oxygen content exceeds 2.628 wt%.

Newport Inc. was licensed recently by the National Renewable Energy Laboratory of the United States to update the highest efficiency of the perovskite solar cell (PSC) certification of PSCs by 23.7%. Exploring new hole transfer layer is the key to the future development of PSC. In this paper, we constructed seven organic hole transport material molecules such as copper-phthalocyanine (CuPc), 2',7'-bis(bis(4-methoxyphenyl)amino)spiro[cyclopenta-[2,1-b:3,4-b']dithiophene-4,9'-fluorene] (FDT), Poly-triarylamine (PTAA), poly(3,4-ethylenedioxy thiophene)/poly(styrenesulfonate) (PEDOT/PSS) poly(3-hexylthiophene) (P3HT) and six in-organic hole transport material molecules such as CuCSN, CuI, InCuS2, CuO, Cu2O, NiO with Material Studio software. By the structure optimization, their energy band, density of state (DOS), HOMO/lowest unoccupied orbit (LUMO) energy level and absorption spectrum were calculated. Furthermore, the HOMO/LUMO electron cloud distribution map of FDT molecule was analyzed in detail. The results show that the electron cloud is closer to the nucleus with the increase of the isopotential surface value. From the absorption spectra, the absorption wavelengths of most inorganic hole transport materials are mainly concentrated at about 200 nm, which is relatively short. But the absorption wavelengths of organic hole transport materials are distributed in long wavelength region, most of them are above 2000 nm. Only the absorption spectra of PTAA, Spiro OMetad and CuPc are in the range of solar spectrum. The HOMO energy levels of seven organic hole transport materials are slightly higher than the values of valence band of CH3NH3PbI3 and NH2CH = NH2PbI3, which are favorable for carrier injection and transport. The band gap of inorganic hole transport materials CuCSN and CuI is wider. From the energy band structure curve, the effective mass of NiO, CuO, Cu2O carriers is smaller, which the carrier transport rate is relatively high. The hole transport material must have high hole mobility and hole conductivity so as to ensure the effective transport of the hole at the interface between the hole transport layer and the perovskite layer.

The Ji'erzankale Necropolis (吉尔赞喀勒墓地) is located on the Pamir Plateau in the Xinjiang Uyghur Autonomous Region of China. Composed of numerous stone circle graves and directly radiocarbon dated to the Iron Age (ca. 2400–2600 years cal BP), this site is unique in that numerous lines of archaeological evidence suggest that those interred here were followers of the Zoroastrian religion. Here, we present carbon (δ13C) and nitrogen (δ15N) stable isotope ratio measurements of seeds (Nitraria pamirica, n = 7), animals (n = 14), and humans (n = 24) to reconstruct ancient diet and lifeways at the Ji'erzankale Necropolis. The results of the N. pamirica reflect the natural C3 vegetation and arid environment of this region. The δ13C (mean ± SD = –18.6 ± 0.8‰) and δ15N (mean ± SD = +8.1 ± 1.6‰) results of the animals (13 sheep and 1 hare) display a mostly C3 terrestrial diet with variable levels of protein consumption. Adult humans (n = 19) have δ13C (mean ± SD = –17.9 ± 0.2‰) and δ15N (mean ± SD = +13.1 ± 0.3‰) results that tightly cluster above the sheep by approximately +5‰. This is evidence that the diet of this population was relatively homogenous and mainly based on sheep and/or their secondary products and did not have a large input of C4 crops such as foxtail (Setaria italica) or common millet (Panicum miliaceum).

In this study, the corrosion resistance of titanium nitride (TiN), nitrogen titanium carbide (TiCN) and titanium-diamond-like carbon (Ti-DLC) films deposited on 316L stainless steel (SS) were compared via differences in the surface and section-cross morphologies, open circuit potential tests, electrochemical impedance spectroscopy and potentiometric tests. The corrosion resistance of the TiCN and Ti-DLC films significantly improved because of the titanium carbide (TiC) crystals that obstruct the corrosive species penetrating the as-deposited film in the electrolyte atmosphere. TiN exhibited the lowest corrosion resistance because of its low thickness and high volume of defects. The Ti-DLC film showed the lowest corrosion current density (approximately 4.577 μA/cm2) and thickness reduction (approximately 0.12 μm) in different electrolytes, particularly those with high Cl− and H+ concentrations, proving to be the most suitable corrosion protection material for 316L SS substrates.

TiN, TiCN, and Ti-diamond-like carbon (DLC) films were coated on 316L stainless steel surfaces by physical vapor deposition. All films exhibited uniform and dense surfaces with good adhesion. The Ti-DLC film demonstrated the lowest surface roughness. TiC and free C were observed in both the TiCN and Ti-DLC films. Among the three films, the TiCN film demonstrated the highest hardness and elastic modulus, followed by the Ti-DLC film and finally the TiN film. Under dry conditions, all films exhibited significantly lower coefficients of friction than stainless steel. The Ti-DLC film showed the lowest coefficient of friction and is thus considered an ideal anti-wear material for orthodontic applications. The friction mechanisms of the three films were also compared. Therefore, this study provides experimental data and a theoretical basis that may guide the production and modification of dental braces.

In this work, a new adhesion model is proposed to analyze the peeling behavior of hyperelastic beams from a rigid flat substrate by utilizing a recently developed finite strain Euler beam model and the concept of adhesion energy. Both the large strain effect and bending effect are taken into account in the model. Hence, the model can be seen as a generalization of the extensible elastica-type adhesion model to the finite strain case, and it can also be taken as a generalization of the hyperelastic membrane-type adhesion model to the hyperelastic beam case. In the modeling process, the variational method is used to derive the equilibrium equation and associated boundary conditions, including one that physically means the local peeling (fracture) criterion. A first integral is found for hyperelastic beams and it is used to derive an equivalent global peeling criterion. Moreover, an analytical formula for the peeling force during steady peeling is also obtained. Furthermore, numerical solution procedures and results are presented to discuss the effects of large strain and bending deformation on the peeling behavior of the hyperelastic beam. The developed model will contribute to the modeling and understanding of the adhesion and fracture behaviors of soft structures and biomimetic adhesives.

In this study, the effects of the addition of carbonyl nickel powder on the density, microstructure, and mechanical properties of sintered yttria-stabilized zirconia (3YSZ) were investigated. Sintering at 1300 °C resulted in the optimum comprehensive mechanical properties. The addition of 5 vol% carbonyl Ni increased the fracture toughness and flexural strength from 9.51 MPa m1/2 to 14.5 MPa m1/2 and from 747 MPa to 873 MPa, respectively. The addition of carbonyl nickel showed greater improvement than did the addition of spherical Ni powder. The dendritic morphology improved the interface bonding between the ceramic and the metal, enabling a bridging mechanism of the ductile phase. However, further Ni addition decreased the mechanical properties. X-ray diffraction results showed that the amounts of the monoclinic phase (M) and cubic phase (C) of 3YSZ increased, whereas the amount of the tetragonal phase (T) decreased. The Y segregation near the Ni particles, which was confirmed by an energy dispersive spectrometer (EDS), caused the phase changes. The segregation of Y occurred during the cooling stage, rather than the holding stage, of sintering. During the cooling stage, the heat mismatch between Ni and ZrO2 resulted in strong elastic strain energy, which promoted Y segregation.

This article examines the semiotic landscape of the Chinatown in Incheon, South Korea. Using the geosemiotic framework as a heuristic guide, we analyze how the spectacle of Chinatown is constituted through spatial, linguistic, semiotic, and material resources, and find that the unordinariness of the place is contingent on and emerges through its juxtaposition with ordinary space, practice, and language use. We suggest this apparent paradox can be understood through the process of scaling, during which signs and practices that might have been considered quotidian become monumentalised and ritualised when they are transported across timescales and spatial scales. Incheon's Chinatown then affords an opportunity to understand the semiotic and material production of ‘unordinariness’ through ‘ordinariness’. These collective spatiotemporal disjunctures or juxtapositions reveal unexpected but nonetheless crucial intersections among language, semiotics, and nationness.

By adding trace amounts of graphite to metal injection-molded 17-4PH stainless steel, the effects of carbon content on the lattice distortion, nano-copper phase precipitation, and mechanical properties were studied. As the carbon content increased, the distortion degree of martensite increased. Differential scanning calorimetry results showed that the martensitic phase-transformation starting temperature decreased as the carbon content increased. Moreover, the average size of nano-copper-rich precipitates gradually decreased with the carbon content. As a result, the tensile strength and hardness of the samples increased while the elongation correspondingly decreased. Aging promoted greater nano-copper precipitate sizes and slightly improved mechanical properties.

In this study, TiN, TiCN, and Ti-diamond-like carbon (Ti-DLC) films were coated on 316 L stainless steel (AISI 316 L) substrate surface by physical vapor deposition. The biocompatibility of the three films (TiN, TiCN, and Ti-DLC) and three metals (AISI 316 L, Ti, and Cu) was compared on the basis of the differences in the surface morphology, water contact angle measurements, CCK-8 experiment results, and flow cytometry test findings. The biocompatibility of the TiN and TiCN films is similar to that of AISI 316 L, which has good biocompatibility. However, the biocompatibility of the Ti-DLC films is relatively poor, which is mainly due to the inferior hydrophobicity and large amount of sp2 phases. The presence of TiC nanoclusters on the surface of the Ti-DLC film aggravates the inferior biocompatibility. Compared to the positive Cu control group, the Ti-DLC film had a higher cell proliferation rate and lower cell apoptosis rate. Although the Ti-DLC film inhibited cell survival to a certain extent, it did not show obvious cytotoxicity. TiN and TiCN displayed excellent performance in promoting cell proliferation and reducing cytotoxicity; thus, TiN and TiCN can be considered good orthodontic materials, whereas Ti-DLC films require further improvement.