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Alkynyl-protected metal nanoclusters possess unique advantages, and the recent progress on the controllable synthesis and CO2 electroreduction application is discussed, with some explicit examples to elaborate the structure-performance relationship.

Nowadays, people’s life is permeated by the Internet. Internet development has been seized as a commercial opportunity by businesses. An increasing number of enterprises started to use the Internet to spread awareness. This is known as the network effect, and the products which became famous through this way are called internet celebrity products. It is believed that the Internet is providing and will be creating a huge business opportunity as it becomes ever more prevalent. Yeezy has masterly used exciting, word-of-mouth, and hunger marketing as a typical example of enterprises that have successfully generated network effects. Its marketing strategy is worthy of studying and valuable for reference. In the exploration, Yeezy’s marketing strategy will be studied. In order to discover its marketing limitations and the perspectives of the enterprise by its biggest potential consumer——Generation Z, the survey will be handled and analyzed.

Considering the opening of high-speed railway (HSR) as a quasi-natural experiment, this paper explores the emission reduction effect of HSR opening and its mechanisms and heterogeneity characteristics based on the panel data of 272 cities in China from 2006 to 2019 by Staggered DID model and the mediating effect model. It is found that:(1)the opening of HSR significantly reduces the carbon emission level of cities, and the conclusion still holds after controlling the endogeneity issue and a series of robustness tests;(2) Bancon decomposition and negative weight diagnostics both show that the estimated average treatment effect bias is small and the robust estimators are more robust;(3) by reducing production costs and promoting inter-regional industrial division of labor, the opening of HSR promotes intra-industrial structural transformation and inter-industrial structural transformation respectively, thus reducing urban carbon emissions. At the same time, HSR achieves urban carbon emission reduction by promoting free movement of population and human capital agglomeration;(4) further study finds that there is regional heterogeneity in the emission reduction effect of HSR opening, and the carbon reduction effect is mainly reflected in large and medium-sized cities, near provincial capitals, non-resource-based cities, and cities with scarce educational resources, which indicates that the location of future HSR should be combined with the city's own characteristics and be tailored to the city.

The intestinal epithelium is susceptible to heat stress (HS), which leads to gut leakage and inflammation. However, the mechanisms underlying HS-induced intestine dysfunction have yet to be elucidated. We established an in vitro chronic heat exposure-induced intestinal injury of intestinal porcine epithelial cells (IPEC-J2) exposed to high temperatures (43 °C) for 12 h. The results revealed that HS increased reactive oxygen species (ROS) generation and decreased superoxide dismutase 2 (SOD2) expression, leading to oxidative stress. Western blotting analysis demonstrated that HS induced apoptosis as evidenced by increased cytochrome

Environmental pollution remains a serious sustainable development issue. Enterprises, as important agents of sustainable development, are receiving increasing attention regarding their efforts to protect the environment. The rapid development of the digital economy has become a new driver of corporate environmental governance and environmental performance improvements, marking a new sustainable development path. We study the environmental effects of corporate digital transformation from the perspective of environmental performance using Chinese A-share listed companies. We construct a two-step systematic GMM econometric model and find that corporate digital transformation significantly improves environmental performance. Heterogeneity analysis shows that environmental performance improvement through digital transformation is more pronounced among state-owned, large, and heavily polluting enterprises. Mechanistic analysis shows that corporate digital transformation mainly improves environmental performance by enhancing green technological innovation and corporate governance. Further analysis shows a nonlinear relationship between corporate digital transformation and environmental performance. The research not only analyzes the impact of corporate digital transformation on environmental performance from multiple dimensions but also discovers the transmission mechanism of digital transformation that affects environmental performance and verifies a possible nonlinear relationship, providing a theoretical basis and practical reference for promoting corporate digital transformation and sustainable development.

Increasing evidence suggests stem cells from human exfoliated deciduous teeth (SHEDs) serve as desirable sources of dentin regeneration. Photobiomodulation (PBM) has shown great potential in enhancing the proliferation and osteogenesis of human bone marrow mesenchymal stem cells (hBMMSCs). However, the specific role of PBM in odontogenic differentiation of SHEDs is little know, and we further investigated potential mechanism of PBM osteo/odontogenisis. A 980 nm diode laser with different energy densities of (0.5, 5, 10 J cm

Rice (Oryza sativa L.) is a major source of dietary cadmium (Cd). Developing rice varieties with lower levels of Cd in the grain offers an economical and practical way to improve food safety, especially in areas with high Cd contamination. However, the genetic mechanism of Cd accumulation in rice grain is not fully understood. Here, we identified eight QTLs for Cd accumulation in rice grain based on substitution mapping using single segment substitution lines (SSSLs). The QTLs were located on 7 chromosomes, and named qCd-2-1, qCd-3-1, qCd-3-2, qCd-5-1, qCd-6-1, qCd-7-1, qCd-8-1 and qCd-11-1 accordingly. Two of them, qCd-5-1 and qCd-6-1 are reported here for the first time. The haplotypes of candidate genes associated with heavy metal metabolism, especially Cd accumulation, were analyzed in detail. All SSSLs harbouring alleles from donor parents significantly decreased Cd accumulation with additive effects ranging from − 0.061 to -0.105. Six pyramided lines were developed based on crossing and maker-assisted selection, and these six pyramided lines showed significantly decreased Cd content in grain compared with that of the elite, indica recurrent parent, HJX74, while most of agronomic characteristics of the pyramided lines were similar to HJX74. Taken together, this study demonstrates that identifying and pyramiding QTLs for lower Cd accumulation is an effective strategy for developing rice varieties with lower grain Cd accumulation.

Macrophages actively participate in immunomodulatory processes throughout periodontal inflammation. Regulation of M1/M2 polarization affects macrophage chemokine and cytokine secretion, resulting in a distinct immunological status that influences prognosis. Semaphorin 3A (Sema3A), a neurite growth factor, exerts anti-inflammatory effects. In this study, we investigated the immunomodulation of Sema3A on macrophage-related immune responses in vivo and in vitro. Topical medications of Sema3A in mice with periodontitis alleviated inflammatory cell infiltration into gingival tissue and reduced areas with positive IL-6 and TNFα expression. We observed that the positive area with the M2 macrophage marker CD206 increased and that of the M1 macrophage marker iNOS decreased in Sema3A-treated mice. It has been postulated that Sema3A alleviates periodontitis by regulating alternative macrophage activation. To understand the mechanism underlying Sema3A modulation of macrophage polarization, an in vitro macrophage research model was established with RAW264.7 cells, and we demonstrated that Sema3A promotes LPS/IFNγ-induced M1 macrophages to polarize into M2 macrophages and activates the PI3K/AKT/mTOR signaling pathways. Inhibition of the PI3K signaling pathway activation might reduce anti-inflammatory activity and boost the expression of the inflammatory cytokines, iNOS, IL-12, TNFα, and IL-6. This study indicated that Sema3A might be a feasible drug to regulate alternative macrophage activation in the inflammatory response and thus alleviate periodontitis.

Na era atual em que vários setores tradicionais estão a ser substituídos por serviços e produtos digitais, a inovação digital e a inovação tecnológica desenvolvem-se a um ritmo muito mais acelerado ao comparar com o passado. Deste modo, surgiram empresas que desenvolvem grandes plataformas de comunicação, comércio, pesquisa entre outras. Estas grandes plataformas introduzem mudanças significantes. A digitalização tem um papel crucial no avanço da tecnologia na China. Fintech, Healthtech, Edtech, E-commerce são expressões que aparecem devido ao surgimento de grandes plataformas que fornecem digitalmente serviços tradicionalmente presenciais. Ao longo desta dissertação foram analisados vários aspetos relacionados com as dinâmicas de inovação das plataformas virtuais chinesas. Foram estudadas plataformas de duas empresas chinesas: Alibaba e Tencent. Para uma melhor compreensão da posição das empresas, foi feita uma análise intensiva de dados secundários, assim como estudos comparativos com empresas do mesmo setor. Para uma melhor compreensão das estratégias de inovação, foi também feita uma análise de dados qualitativos através da análise de artigos científicos. Nowadays, many traditional sectors have been substituted by digital products and services. The digital innovation and innovation technology are developing in a much higher speed compared to the past. Therefore, many big companies developed huge digital platforms for communication, commerce, searching and other functions. These big platforms introduce big changes in our lives. Digitalization is playing a crucial role in the advancement of technology in China. Fintech, Healthtech, Edtech, E-commerce are some expressions that appeared due to the raise of big platforms that provide digital services which substitutes traditionally presential services. In this dissertation, many aspects related to the digital platforms dynamics of innovation had been analyzed. Two companies had been studied: Alibaba and Tencent. For a better understanding of the position of these two companies in the sector, a deeply analysis of secondary data has been made, as well as comparative studies of these two companies. For a better understanding of the innovation strategies, a qualitative analysis also has been made through scientific articles.

Purpose The aim of this study was to evaluate the effect of photobiomodulation (PBM) on stem cells from human exfoliated deciduous teeth (SHED) odontogenic differentiation and biomineralization potential at various different energy fluences. Methods One control group (without irradiation) and four testing groups (irradiation at 0.5, 5.0 and 10.0 J/cm2 with 10s exposure time) were designed. Cell viability of SHED in response to varying energy fluences of PBM was investigated by the Cell Counting Kit-8 assay. Biomineralization abilitiy of different groups was determined by alkaline phosphatase (ALP) staining and Alizarin Red S (ARS) staining. The qRT-PCR and western blotting were conducted to measure the levels of genes and proteins related to SHED odontogenic differentiation. Results PBM at 0.5 J/cm2 significantly promoted SHED proliferation compared to the control group. In addition, PBM at 5.0 J/cm2 significantly upregulated the expression of osteo-/odontogenic genes including runt-related transcription factor 2 (RUNX2), ALP, bone morphogenetic protein 2 (BMP2), dentin sialophosphoprotein (DSPP) and dentin matrix acidic phosphoprotein 1 (DMP1). Moreover, The PBM at 5.0 J/cm2 modulate the components of the BMP/Smad and Wnt signaling pathway involves in BMP2, p-Smad 1/5/9, p-β-catenin and RUNX2. Conclusion PBM could trigger SHED odontogenic differentiation and biomineralization in a dose-dependent manner through the activation of the components of the BMP/Smad and Wnt signaling pathway. These results reveal a promising strategy for application of PBM in for vital pulp therapies of deciduous teeth.

The demand for safe assets has increased in recent years. However, the supply of safe assets has remained concentrated in a few Western developed countries, and it cannot meet the demand for safe a...

We investigate the current induced depinning of magnetic domain walls (DWs) trapped at the kinks in a patterned Py nanowire with two-kink zigzag shape on Si/SiO2 substrate. By injecting pulse current with varying amplitude, two threshold current densities with a slight difference of around $6 \times 10^{10}$ A m−2 have been determined according to the different depinning process. The smaller threshold current density corresponds to the depinning of a single DW which is always the first DW facing to the electron flow. This fact indicates that the different pinning potential caused by the structural asymmetry is not the key to determine which DW is to depin. Micromagnetic simulations provide evidence that the specific current-driven behavior of the vortex DW might account for the single depinning process. The larger threshold corresponds to the simultaneous depinning of two DWs which has been commonly observed in a variety of shaped nanowires. This asynchronous depinning phenomenon provides the possibility of the selective DW depinning in the future logic devices.

Haze pollution has been addressed in extensive studies over the last few years. However, the relationship between resource dependence and haze pollution has not been fully investigated. This study focuses on addressing this problem while considering the mediating role of green technology innovation. A panel dataset of 263 prefecture-level cities in China from 2005 to 2018 is used for the analysis. The results show the following: (1) the two-way fixed-effect model reveals that resource dependence contributes significantly to haze pollution, and this finding remains robust across a series of robustness tests. (2) A mediation analysis indicates that resource dependence is unfavorable for green technology innovation, indirectly affecting the alleviation of haze pollution. (3) The results of panel threshold regression suggest that green technology innovation promotes haze reduction in the weak and medium resource dependence stages, whereas this optimization effect disappears in the strong resource dependence stage due to rebound effects. (4) The results of regional heterogeneity demonstrate that the positive effects of resource dependence on haze pollution exist in eastern and western China but not in central China. Based on these results, policy implications are given to reduce haze pollution.

We investigate the evolution of plasmonic spectral features from weak to strong coupling regime, with a large Rabi splitting of 210 meV, in the designed dimer-grating metamaterial. The two-driven coupled oscillator model has been proposed to quantitatively analyze the evolution, where the two oscillators are directly excited by the external driving light wave, demonstrating that the evolution is caused by not only aligning the resonance wavelength of related SP modes, but also low-loss. The proposed metamaterial is of high magnetoplasmonic refractive index sensitivity of 280.05 nm RIU−1 and figure of merit of 3*104 RIU−1, suggesting promising applications in biochemical sensing.

To address climate change, one of the toughest contemporary environmental issues, growing importance is attached to the role of the digital economy in combating environmental degradation. Using panel data from 237 Chinese cities during the period 2011-2018, this paper attempts to provide a more systematic view of the relationship between the digital economy and urban low-carbon sustainable development to make up for the existing empirical inconclusiveness. Based on the fixed-effect model, results show that boosting the digital economy can effectively promote urban low-carbon sustainable development, and the conclusion remains robust across a series of robustness checks. Furthermore, innovation factor mobility is the critical transmission channel through which the digital economy affects urban low-carbon sustainable development. Spatiotemporal heterogeneity analysis reveals that the promoting effect of the digital economy on urban low-carbon sustainable development decreases from the northeast to the southeast of China, whereas the impact of innovation factor mobility on urban low-carbon sustainable development decreases from the southeast to the northeast with the Pearl River Delta as the core. Panel threshold regression analysis shows that the impact of the digital economy on urban low-carbon sustainable development is getting stronger with the increase of economic development level charactered with nighttime lights.

Nanofluidic chips with different numbers of nanochannels were fabricated based on a commercial AFM system using a single-scratch approach. The electrical characterization and enzymatic reactions at the nanoscale were demonstrated using the obtained chips. The effects of the number of nanochannels and the solution concentration on the measured electric current were investigated. The influence of the hydrodynamic convection generated from the induced inflow at the end of the nanochannel on the ion transport through the nanochannel was also studied. Moreover, the enzymatic reactions for trypsin towards poly-l-lysine (PLL) or thrombin were conducted with a nanofluidic chip to investigate the reaction specificity between trypsin and PLL. Results show that the electric current change during the experimental process could be used as a label-free indicator to detect the enzymatic activity.

Turbofan engine is a critical aircraft component with complex structure and high-reliability requirements. Effectively predicting the remaining useful life (RUL) of turbofan engines has essential significance for developing maintenance strategies and reducing maintenance costs. Considering the characteristics of large sample size and high dimension of monitoring data, a hybrid health condition prediction model integrating the advantages of autoencoder and bidirectional long short-term memory (BLSTM) is proposed to improve the prediction accuracy of RUL. Autoencoder is used as a feature extractor to compress condition monitoring data. BLSTM is designed to capture the bidirectional long-range dependencies of features. A hybrid deep learning prediction model of RUL is constructed. This model has been tested on a benchmark dataset. The results demonstrate that this autoencoder-BLSTM hybrid model has a better prediction accuracy than the existing methods, such as multi-layer perceptron (MLP), support vector regression (SVR), convolutional neural network (CNN) and long short-term memory (LSTM). The proposed model can provide strong support for the health management and maintenance strategy development of turbofan engines.

Background: First permanent molars (FPMs) are the most critical teeth in the dental arc. Meanwhile they bear the highest risk for carious lesions. The aim of this study was to investigate the caries status of primary and permanent teeth among 8-9-year-old children in Guangzhou, and the correlation between the caries of primary molars and first permanent molars (FPMs).Methods: 119 samples of children aged 8-9 were included. The scoring and evaluation were processed in accordance with International Caries Detection and Assessment System (ICDAS). Statistical analysis was performed using SPSS 20.0 software package by means of Pearson Chi-square test and Kendall’s correlation.Results: Pearson Chi-Square test showed that the prevalence of dental caries of the first primary molars, second primary molars and primary molars had significant correlation with that of FPMs, while Kendall’s correlation analysis showed that they had weak positive correlation. What’s more, the Pearson chi-square test showed that there was no significant correlation between the degree of dental caries of different primary molars and FPMs.Conclusion: Caries in primary molars, especially the second molars, were considered to be a risk indicator for the development of permanent molars in the future. However, regardless of the degree of primary molars caries, the susceptibility of FPMs caries should be aware of. And pit and fissure sealants for them should be carried out as soon as possible.

A facile two-step method is developed for large-scale synthesis of chemically ordered Pt3Co nanoparticles (NPs) as a high-performance catalyst for hydrogen evolution reaction. Due to the NaCl-matrix as dispersing media avoids the severe aggregation during the high-temperature annealing process, the resulting Pt3Co NPs are pure and well crystallized with narrow size distribution. Furthermore, the chemically ordered Pt3Co NPs exhibit excellent HER property in acidic solution. Our methodology can be also applied to synthesis of other Pt-based NPs.

The properties of the optics and transverse magneto-optical Kerr effect (TMOKE) of one-dimensional magnetoplasmonic nanostructures are experimentally investigated. It shows that the resonant dips of the reflectance spectra and the enhancement of the TMOKE of the designed structures are attributed to the excitation and the coupling of the localized surface plasmon (LSP) and surface plasmon polariton (SPP) modes. Moreover, the insertion of the nonmagnetic dielectric SnO2 layer into the quadrilayer structure of Ag/Co/SnO2/Ag can not only pronouncedly enhance the TMOKE signals of the sample but also prompt their resonant positions to generate a blueshift. It has been demonstrated that the enhancement of the TMOKE signal and the blueshift of the resonant wavelength of the TMOKE stems from the coupling of SPP of the two different interfaces of the silver film.