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Reducing noise in CT images and extracting key features are crucial for improving the accuracy of medical diagnoses, but it remains a challenging problem due to the complex characteristics of CT images and the limitations of existing methods. It is worth noting that multiple views can provide a richer representation of information compared to a single view, and the unique advantages of the wavelet transform in feature analysis. In this study, a novel Multi-View Weighted Feature Fusion algorithm called MVWF is proposed to address the challenge of enhancing CT image recognition utilizing wavelet transform and convolutional neural networks. In the proposed approach, the wavelet transform is employed to extract both detailed and primary features of CT images from two views, including high frequency and low frequency. To mitigate information loss, the source domain is also considered as a view within the multi-view structure. Furthermore, AlexNet is deployed to extract deeper features from the multi-view structure. Additionally, the MVWF algorithm introduces a balance factor to account for both specific information and global information in CT images. To accentuate significant multi-view features and reduce feature dimensionality, random forest is used to assess feature importance followed by weighted fusion. Finally, CT image recognition is accomplished using the SVM classifier. The performance of the MVWF algorithm has been compared with classical multi-view algorithms and common single-view methods on COVID-CT and SARS-COV-2 datasets. The experimental results indicate that an average improvement of 6.8% in CT image recognition accuracy can be achieved by utilizing the proposed algorithm. Particularly, the MVF algorithm and MVWF algorithm have attained AUC values of 0.9972 and 0.9982, respectively, under the SARS-COV-2 dataset, demonstrating outstanding recognition performance. The proposed algorithms can capture more robust and comprehensive high-quality feature representation by considering feature correlations across views and feature importance based on Multi-view. [ABSTRACT FROM AUTHOR]

In light of a scarcity of research on the spatial effects of urbanization on poverty reduction, this study uses panel data on 30 provinces in China from 2009 to 2019 to construct a system of indices to assess poverty that spans the four dimensions of the economy, education, health, and living. We use the spatial autocorrelation test and the spatial Durbin model (SDM) to analyze the spatial effects of urbanization on poverty reduction in these different dimensions. The main conclusions are as follows: (a) China's urbanization has the characteristics of spatial aggregation and a spatial spillover effect. (b) Different dimensions of poverty had the attributes of spatial agglomeration, and Moran's index of a reduction in economic poverty was the highest. Under the SDM, the different dimensions of poverty also showed a significant positive spatial correlation. (c) Urbanization has a significant effect on poverty reduction along the dimensions of the economy, education, and living, but has little effect on reducing health poverty. It has a spatial spillover effect on poverty reduction in economic and living contexts. (d) There were spatial differences in the effect of urbanization on relieving economic and living-related poverty. [ABSTRACT FROM AUTHOR]

Background: Secondary bacterial infections and pneumonia are major mortality causes of respiratory viruses, and the disruption of the upper respiratory tract (URT) microbiota is a crucial component of this process. However, whether this URT dysbiosis associates with the viral species (in other words, is viral type-specific) is unclear. Results: Here, we recruited 735 outpatients with upper respiratory symptoms, identified the infectious virus types in 349 participants using multiplex RT-PCR, and profiled their upper respiratory microbiome using the 16S ribosomal RNA gene and metagenomic gene sequencing. Microbial and viral data were subsequently used as inputs for multivariate analysis aimed at revealing viral type-specific disruption of the upper respiratory microbiota. We found that the oropharyngeal microbiota shaped by influenza A virus (FluA), influenza B virus (FluB), respiratory syncytial virus (RSV), and human rhinovirus (HRV) infections exhibited three distinct patterns of dysbiosis, and Veillonella was identified as a prominent biomarker for any type of respiratory viral infections. Influenza virus infections are significantly correlated with increased oropharynx microbiota diversity and enrichment of functional metabolic pathways such as L-arginine biosynthesis and tetracycline resistance gene tetW. We used the GRiD algorithm and found the predicted growth rate of common respiratory pathogens was increased upon influenza virus infection, while commensal bacteria, such as Streptococcus infantis and Streptococcus mitis, may act as a colonization resistance to the overgrowth of these pathogens. Conclusions: We found that respiratory viral infections are linked with viral type-specific disruption of the upper respiratory microbiota, particularly, influenza infections uniquely associated with increased microbial diversity and growth rates of specific pathogens in URT. These findings are essential for clarifying the differences and dynamics of respiratory microbiota in healthy participants and acute respiratory viral infections, which contribute to elucidating the pathogenesis of viral-host-bacterial interactions to provide insights into future studies on effective prevention and treatment of respiratory tract infections. AxMbpzHUJuHXyJKsbr5ywR Video Abstract [ABSTRACT FROM AUTHOR]

Compared to fixed orthodontic appliances with brackets, thermoplastic invisible orthodontic aligners offer several advantages, such as high aesthetic performance, good comfort, and convenient oral health maintenance, and are widely used in orthodontic fields. However, prolonged use of thermoplastic invisible aligners may lead to demineralization and even caries in most patients' teeth, as they enclose the tooth surface for an extended period. To address this issue, we have created PETG composites that contain piezoelectric barium titanate nanoparticles (BaTiO3NPs) to obtain antibacterial properties. First, we prepared piezoelectric composites by incorporating varying amounts of BaTiO3NPs into PETG matrix material. The composites were then characterized using techniques such as SEM, XRD, and Raman spectroscopy, which confirmed the successful synthesis of the composites. We cultivated biofilms of Streptococcus mutans (S. mutans) on the surface of the nanocomposites under both polarized and unpolarized conditions. We then activated piezoelectric charges by subjecting the nanocomposites to 10 Hz cyclic mechanical vibration. The interactions between the biofilms and materials were evaluated by measuring the biofilm biomass. The addition of piezoelectric nanoparticles had a noticeable antibacterial effect on both the unpolarized and polarized conditions. Under polarized conditions, nanocomposites demonstrated a greater antibacterial effect than under unpolarized conditions. Additionally, as the concentration of BaTiO3NPs increased, the antibacterial rate also increased, with the surface antibacterial rate reaching 67.39% (30 wt% BaTiO3NPs). These findings have the potential for application in wearable, invisible appliances to improve clinical services and reduce the need for cleaning methods. [ABSTRACT FROM AUTHOR]

Baicalin (7‐d‐glucuronic acid‐5, 6‐dihydroxyflavone) derived from the root of Scutellaria baicalensis used as Traditional Chinese Medicine (TCM) has been revealed to exert potential antiviral activity via various pathways, while the molecular mechanisms have not been fully understood. Pyroptosis, an inflammatory form of programmed cell death (PCD), is reported to play a crucial role in host cell fate during viral infection. In this study, transcriptome analysis of mice lung tissue reveals that baicalin reverses the alterations of the mRNA levels of PCD‐associated genes upon H1N1 challenge, with a concomitant decrease in the population of H1N1‐induced propidium iodide (PI)+ and Annexin Ⅴ+ cells. Intriguingly, we find that baicalin contributes to the survival of infected lung alveolar epithelial cells partly through its inhibition of H1N1‐induced cell pyroptosis, which is manifested by reduced bubble‐like protrusion cells and lactate dehydrogenase (LDH) release. Moreover, the antipyroptosis effect of baicalin in response to H1N1 infection is found to be mediated by its repression on caspase‐3/Gasdermin E (GSDME) pathway. Cleaved caspase‐3 and N‐terminal fragment of GSDME (GSDME‐N) are detected in H1N1‐infected cell lines and mice lung tissues, which are markedly reversed by baicalin treatment. Furthermore, inhibition of caspase‐3/GSDME pathway by caspase‐3 inhibitor or siRNA exerts an antipyroptosis effect equal to that of baicalin treatment in infected A549 and BEAS‐2B cells, indicating a pivotal role of caspase‐3 in the antiviral activities of baicalin. Conclusively, for the first time, we demonstrate that baicalin could effectively suppress H1N1‐induced pyroptosis of lung alveolar epithelial cells via caspase‐3/GSDME pathway both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

In this paper, the stochastic stability of networked control systems (NCSs) with nonlinear perturbation and parameter uncertainties is studied. A decentralized dynamic event triggering scheme (DDETS) is introduced to reduce energy consumption and network transmission burden. Each channel can decide whether to transmit signals sampled by corresponding sensors through this mechanism. Due to the unreliability of communication network, a new mathematical model of NCSs based on multi‐channel fading and hybrid cyber attacks is established, and the actuator is constrained by saturation. A sufficient condition for stochastic stability based on static controller is derived through Lyapunov stability theory, and two numerical examples are given to demonstrate the effectiveness of the method. [ABSTRACT FROM AUTHOR]

In this article, the quasi-consensus problem of the Markovian switching heterogeneous multi-agent system with cooperative–competitive interactions and parameter uncertainties is investigated. The switch of the agent's dynamics is combined with Markov processes, and the topologies among agents switch between cooperation and competition. Based on graph theory and Lyapunov function theory, the sufficient conditions are given to ensure the quasi-consensus of the Markovian switching multi-agent system. Finally, a numerical simulation is given to illustrate the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

In light of a scarcity of research on the spatial effects of urbanization on poverty reduction, this study uses panel data on 30 provinces in China from 2009 to 2019 to construct a system of indices to assess poverty that spans the four dimensions of the economy, education, health, and living. We use the spatial autocorrelation test and the spatial Durbin model (SDM) to analyze the spatial effects of urbanization on poverty reduction in these different dimensions. The main conclusions are as follows: (a) China's urbanization has the characteristics of spatial aggregation and a spatial spillover effect. (b) Different dimensions of poverty had the attributes of spatial agglomeration, and Moran's index of a reduction in economic poverty was the highest. Under the SDM, the different dimensions of poverty also showed a significant positive spatial correlation. (c) Urbanization has a significant effect on poverty reduction along the dimensions of the economy, education, and living, but has little effect on reducing health poverty. It has a spatial spillover effect on poverty reduction in economic and living contexts. (d) There were spatial differences in the effect of urbanization on relieving economic and living-related poverty. [ABSTRACT FROM AUTHOR]

The oral and upper respiratory tracts are closely linked anatomically and physiologically with the lower respiratory tract and lungs, and the influence of oral and upper respiratory microbes on the lung microbiota is increasingly being recognized. However, the ecological process and individual heterogeneity of the oral and upper respiratory tract microbes shaping the lung microbiota remain unclear owing to the lack of controlled analyses with sufficient sample sizes. Here, the microbiomes of saliva, nasal cavity, oropharyngeal area, and bronchoalveolar lavage samples are profiled and the shaping process of multisource microbes on the lung microbiota is measured. It is found that oral and nasal microbial inputs jointly shape the lung microbiota by occupying different ecological niches. It is also observed that the spread of oral microbes to the lungs is heterogeneous, with more oral microbes entering the lungs being associated with decreased lung function and increased lung proinflammatory cytokines. These results depict the external shaping process of lung microbiota and indicate the great value of oral samples, such as saliva, in monitoring and assessing lung microbiota status in clinical settings. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR), with increasing incidence, is the major cause of vision loss and blindness worldwide in working-age adults. Diabetic macular edema (DME) remains the main cause of vision impairment in diabetic patients, with its pathogenesis still not completely elucidated. Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of DR and DME. Currently, intravitreal injection of anti-VEGF agents remains as the first-line therapy in DME treatment due to the superior anatomic and functional outcomes. However, some patients do not respond satisfactorily to anti-VEGF injections. More than 30% patients still exist with persistent DME even after regular intravitreal injection for at least 4 injections within 24 weeks, suggesting other pathogenic factors, beyond VEGF, might contribute to the pathogenesis of DME. Recent advances showed nearly all the retinal cells are involved in DR and DME, including breakdown of blood-retinal barrier (BRB), drainage dysfunction of Müller glia and retinal pigment epithelium (RPE), involvement of inflammation, oxidative stress, and neurodegeneration, all complicating the pathogenesis of DME. The profound understanding of the changes in proteomics and metabolomics helps improve the elucidation of the pathogenesis of DR and DME and leads to the identification of novel targets, biomarkers and potential therapeutic strategies for DME treatment. The present review aimed to summarize the current understanding of DME, the involved molecular mechanisms, and the changes in proteomics and metabolomics, thus to propose the potential therapeutic recommendations for personalized treatment of DME. [ABSTRACT FROM AUTHOR]

In recent years, hazardous wastewater treatment has been a complex and global problem. In this work, by considering the antimicrobial activity of Ag nanoparticles (AgNPs) and reduced graphene oxide (rGO), we constructed an antibacterial device (G-AgNP) with AgNPs conformably deposited onto a 3D scaffold of reduced graphene oxide in situ. The major limitation, which is difficult to recycle, of two-dimensional graphene-silver composite materials in previous studies is improved. Characterization techniques, SEM, TEM, XRD, and XPS, confirmed the synthesis of nanocomposites. Attributed to its larger specific area, more active sites, and synergistic enhancement, the G-AgNP device demonstrated the best bacterial removal capacity, with an antibacterial rate for both E. coli and S. aureus as high as 100% at quite low AgNP contents. The reported G-AgNP has potential application as a wearable sewage treatment device and for the protection of wearable sensors as a promising sterilizing candidate based on its high and stable antibacterial efficiency. [ABSTRACT FROM AUTHOR]

In order to study the impact of continuous vaccination and voluntary isolation for the COVID-19, a susceptible-exposed-infected-recovered-quarantine-vaccines (SEIR-QV) model is proposed. A basic regeneration number R 0 is defined to determine the extinction or persistence of the disease. We numerically analyze the impact of key parameters based on actual parameters of COVID-19, such as the vaccination rate, population importation rate, and natural (or causal) mortality transmission rate on the dynamics of disease transmission. Then we obtain sensitivity indices of some parameters on R 0 by sensitivity analysis. Finally, the stability of the system and the effectiveness of the optimal control strategy are verified by numerical simulation. [ABSTRACT FROM AUTHOR]

A series of triazole derivatives containing phenylethynyl pyrazole moiety as side chain were designed, synthesized, and most of them exhibited good in vitro antifungal activities. Especially, compounds 5k and 6c showed excellent in vitro activities against C. albicans (MIC = 0.125, 0.0625 μg/mL), C. neoformans (MIC = 0.125, 0.0625 μg/mL), and A. fumigatus (MIC = 8.0, 4.0 μg/mL). Compound 6c also exerted superior activity to compound 5k and fluconazole in inhibiting hyphae growth of C. albicans and inhibiting drug-resistant strains of C. albicans, and it could reduce fungal burdens in mice kidney at a dosage of 1.0 mg/kg. An in vivo efficacy evaluation indicated that 6c could effectively protect mice models from C. albicans infection at doses of 0.5, 1.0, and 2.0 mg/kg. These results suggested that compound 6c deserves further investigation. [ABSTRACT FROM AUTHOR]

As the leading urban agglomeration in China, the Yangtze River Delta (YRD) is experiencing a factor-driven to innovation-driven transition. However, the dynamics of regional innovation growth are not yet fully understood. This paper combines the complex network methodology with spatial econometrics to disentangle the contributions of innovation endowments, innovation network flows, and innovation network positions to regional innovation growth, as well as their spatial spillover effects. The primary findings suggest that regional innovation growth results from the networked agglomeration economies, which is shaped by the interactions between agglomeration factors and network factors. Specifically, agglomeration factors play a fundamental role in regional innovation growth. In contrast, network factors, such as the network flows and network positions, may contribute to new path creation by promoting access to external innovation resources. Additionally, the institutional factors show multiplexity in fostering regional innovation patterns. Such findings indicate that the YRD region should shift the innovation growth pattern from competitive involution to mutually beneficial cooperation to reduce regional disparities. In this regard, the institutional capacity of organizing network flows and fostering reciprocal inter-city partnerships has become increasingly critical for promoting sustainable innovation and regional development. [ABSTRACT FROM AUTHOR]

Background: Mobile colistin resistance like gene (mcr-like gene) is a new type of polymyxin resistance gene that can be horizontally transferred in the Enterobacteriaceae. This has brought great challenges to the treatment of multidrug-resistant Escherichia coli and K. pneumoniae. Results: K. pneumoniae 16BU137 and E. coli 17MR471 were isolated from the bus and subway handrails in Guangzhou, China. K. pneumoniae 19PDR22 and KP20191015 were isolated from patients with urinary tract infection and severe pneumonia in Anhui, China. Sequence analysis indicated that the mcr-1.1 gene was present on the chromosome of E. coli 17MR471, and the gene was in the gene cassette containing pap2 and two copies of ISApl1.The mcr-1.1 was found in the putative IncX4 type plasmid p16BU137_mcr-1.1 of K. pneumoniae 16BU137, but ISApl1 was not found in its flanking sequence. Mcr-8 variants were found in the putative IncFIB/ IncFII plasmid pKP20191015_mcr-8 of K. pneumoniae KP20191015 and flanked by ISEcl1 and ISKpn26. Conclusion: This study provides timely information on Enterobacteriaceae bacteria carrying mcr-like genes, and provides a reference for studying the spread of mcr-1 in China and globally. [ABSTRACT FROM AUTHOR]

Beam slab structure is often encountered in a complex tunnel boring machine. Beam slab structure is subject to dynamic load, which is easy to cause fatigue damage and affect its service life. Therefore, it is necessary to control the vibration of this kind of beam slab structure. In this study, the central rigid body-flexible beam model is established for the rotating beam and plate rotating around the y-axis. Based on the Hamilton variational principle, the dynamic equation of the central rigid body-flexible beam system is established, and the dynamic model of the central rigid body-flexible beam system considering the influence of Coriolis force and centrifugal force is given. The vibration control of the central rigid body-flexible beam system is studied. The vibration mode of the rotating Euler Bernoulli beam is determined by using the elastic wave and vibration mode theory. The influence of the rotating motion on the beam vibration is analyzed, and the variable structure control law is designed to suppress the beam vibration. Numerical simulation results show that the control method can effectively suppress the first-order and second-order vibration of the beam and verify the effectiveness of the control strategy. [ABSTRACT FROM AUTHOR]

Metropolitan areas are important for engaging in fierce global competition. Cities in metropolitan areas in China are generally characterized by a core-periphery structure. The Yangtze River Delta metropolitan area (YRD) is a national strategic region in which Shanghai, as a central city, drives the economic growth of hinterland cities. Exploring the spatiotemporal characteristics and influencing factors between the central city and its hinterland cities in the YRD can provide a basis for promoting regional development. Based on the headquarters-branches and enterprise investment data from 1978 to 2019, this study analyzes the spatiotemporal characteristics and influencing factors of enterprise linkages between Shanghai and its hinterland cities in the YRD. Our results reveal the following: (1) the headquarters-branch linkages between Shanghai and its hinterland cities manifest polarization characteristics, with different polarized characteristics among the three provinces; (2) the enterprise investment linkages between Shanghai and its hinterland cities are getting closer, but the key cities for investment in each province are different; (3) economic strength is a core factor that affects whether Shanghai establishes enterprise branches in its hinterland cities; and (4) the enterprise investment linkages between Shanghai and its hinterland cities depend on whether a city has a comparative advantage. [ABSTRACT FROM AUTHOR]

Based on the SEIR model, which takes into account prevention and control measures, prevention and control awareness, and economic level and medical level indicators, this paper proposes an infectious disease model of "susceptible-exposed-infected-removed-asymptomatic-isolated" (short for SEIR-AQ) to assess and predict the development of the COVID-19 pandemic with different prevention and control strategies. The kinetic parameters of the SEIR-AQ model were obtained by fitting, and the parameters of the SEIR-AQ model were solved through the Euler method. Furthermore, the effects of different countries' prevention and control strategies on the number of infections, the proportion of isolation, the number of deaths, and the number of recoveries were also simulated. The theoretical analysis showed that measures such as isolation for prevention and control and medical tracking isolation had a significant inhibitory effect on the development of the COVID-19 pandemic, among which stratified treatment and enhanced awareness played a key role in the rapid regression of the peak of COVID-19-infected patients. Conclusion of the Simulation. The SEIR-AQ model can be used to evaluate the development status of the COVID-19 epidemic and has some theoretical value for the prediction of COVID-19. [ABSTRACT FROM AUTHOR]

The accurate identification of urban functional areas is of great significance for optimizing urban spatial structure, rationally allocating spatial elements, and promoting the sustainable development of the city. This paper proposes a method to precisely identify urban functional areas by coupling Open Street Map (OSM) and Point of Interest (POI) data. It takes the central urban area of Hangzhou as a case study to analyze the spatial distribution characteristics of the functional areas. The results show that: (1) The central urban areas of Hangzhou are divided into 21 functional areas (6 single functional areas, 14 mixed functional areas and 1 comprehensive functional area). (2) The single functional areas and the mixed functional areas show the geographical distribution characteristics of the looping stratification, which means "Core-periphery" differentiation is obvious, and the comprehensive functional area is relatively scattered. (3) The mixed degree of regional function with ecological function and production function is low while comprehensive functional areas are usually associated with higher potential and vitality. (4) The identification results are in great agreement with the actual situation of Hangzhou central urban area, and the method is feasible. Therefore, this paper can provide a reference for urban development planning and management. [ABSTRACT FROM AUTHOR]

Considering the large‐scale development of renewable energy resources globally, control optimization of coal‐fired power plants is becoming increasingly crucial. The dynamics of the coordinated control system (CCS) must be studied prior to designing a controller. These dynamics of the subcritical units have been expressed through various modeling methods. However, in previous studies, ordinary differential equations (ODEs) have been primarily employed, which cannot reflect the uncertainties in the system. Therefore, a model with a greater accuracy should be observed to comprise uncorrelated residuals. In this study, the uncertainties in the calorific value of fired coal and combustion process were analyzed first. A normal distribution of disturbance was assumed in this process. The dynamics of the CCS were then described with stochastic differential equations (SDEs). Furthermore, a parameter estimation procedure was designed. The residual evaluation is employed to improve the model evaluation. After simulations, the SDE‐based model‐3 in this study elucidates the dynamics of the subcritical boiler‐turbine system better than the ODE‐based model and other SDE‐based models. The measured values can be regarded as a possible result of this model, rendering it a potential platform to employ stochastic model predictive control in CCS. [ABSTRACT FROM AUTHOR]

Since the financial crisis in 2008, innovation has gradually become the orientation of global economic development and the strategic choice for China's urban development. With the transformation of the urban development mode from factor-driven and capital-driven to innovation-driven, many innovation spaces have begun to emerge in cities, which attract academic attention. A large number of studies on the relation between innovation activities and geographic space mainly focus on the phenomena at the regional level, and the city is only regarded as a target of innovation activities agglomeration. The study on the distribution of innovation space within the city is insufficient. In particular, there is a lack of studies on the spatial-temporal evolution of urban innovation space distribution. However, the study on the spatial-temporal evolution characteristics of urban innovation space distribution can provide planning countermeasures for the construction of innovative cities in China. Taking Nanjing as an empirical area, the spatial-temporal evolution of urban innovation space distribution was studied through methods such as average nearest neighbor, standard deviational ellipse, kernel density estimation, and exploratory spatial data analysis based on the data of high-tech enterprises identified from 2008 to 2019. The results showed the following: (1) the distribution of urban innovation space has significant spatial agglomeration characteristics, and the degree of agglomeration continued to rise; (2) regardless of the macro- or microperspective, the distribution of urban innovation space has shown the characteristic of diffusion at the initial, but the trend of polarization in recent years is significant; and (3) the distribution of urban innovation space exhibited diverse agglomeration modes and evolution trends in different regions, and it can be divided into three categories: grouped, banded, and scattered. [ABSTRACT FROM AUTHOR]

CYP51 (Erg11) belongs to the cytochrome P450 monooxygenase (CYP) superfamily and mediates a crucial step of the synthesis of ergosterol, which is a fungal-specific sterol. It is also the target of azole drugs in clinical practice. In recent years, researches on fungal CYP51 have stepped into a new stage attributing to the discovery of crystal structures of the homologs in Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. This review summarizes the functions, structures of fungal CYP51 proteins, and the inhibitors targeting these homologs. In particular, several drug-resistant mechanisms associated with the fungal CYP51s are introduced. The sequences and crystal structures of CYP51 proteins in different fungal species are also compared. These will provide new insights for the advancement of research on antifungal agents. [ABSTRACT FROM AUTHOR]

Front Cover Caption: The cover image is based on the Research Article Baicalin inhibits influenza A (H1N1)‐induced pyroptosis of lung alveolar epithelial cells via caspase‐3/GSDME pathway by Zhenqiao Wei et al., https://doi.org/10.1002/jmv.28790. [ABSTRACT FROM AUTHOR]

Previous designs of conventional aerodynamic lens have been widely used to focus large nanoparticles. It is a big challenge to focus small sub-10 nm nanoparticles. The focusing of small nanoparticle is controlled by two factors: high diffusivity and low inertia. Here, we made some modification for the aerodynamic lens system designed by Wang et al. (Aerosol Sci Technol 39:624, 1). The capability of focusing sub-10 nm nanoparticles was evaluated by the computational fluid dynamics software FLUENT. From numerical simulations of size-resolved particle trajectories, it was found that most of the small nanoparticles lost to the wall by diffusion. The effect of Brownian diffusion on the particle extraction from lens system is investigated. Simulations have shown that the Brownian diffusion perturbs the trajectories of nanoparticles that are dictated by the carrier gas and increase the probability of nanoparticle deposition on the wall. The effect of lens system geometry on the nanoparticles is also investigated. The results of simulation showed that the geometry of lens system affected the beam diameter and the transmission efficiency of nanoparticle. [ABSTRACT FROM AUTHOR]

Purpose: Colonic perforation is a life-threatening complication after colonic stent insertion as a bridge to surgery for acute obstruction caused by colorectal cancer. The oncological consequence of colonic perforation after emergent surgical intervention was unknown. The aim of this short communication was to investigate whether or not the perforation and emergent surgery had obviously impact on the peritoneal recurrence and long-term survival of patients. Methods: Data of the patients who underwent colorectal stenting as a bridge to surgery in 5 years from 2012 to 2017 was collected by the Endoscopical Surgery Group of Hubei. The perforated cases treated by emergent operation were retrospectively analyzed. Results: During 5 years from 2012 to 2017, 116 cases of colorectal stenting as a bridge to surgery had been performed, and 7 patients had perforation after stent placement and treated by emergent surgery, including 1 case of synchronic liver metastasis treated by one-stage metastasectomy. One of the 7 patients died of septic shock after operation, and the remaining patients were followed up for 6–60 months. There was no evidence of abdominal implantation or extra-abdominal metastasis. Conclusion: This small case series implicated that colonic perforation after stent insertion for malignant colorectal obstruction treated by emergent surgery might not obviously increase the peritoneal implantation and metastasis. [ABSTRACT FROM AUTHOR]

In article number 2203115, Jingxiang Zhang, Guo-Bao Tian, Tao Ding, and co-workers have found that differential input from oral bacteria determines the specific composition of the lung microbiota. They identified two different microbiota pneumo-types and found that a high oral input type of lung microbiota was associated with higher levels of inflammatory cytokines and poorer clinical indices. B Lung Microbiota b The lungs were previously considered sterile, however high-throughput metagenomic sequencing of bronchia-alveolar lavage fluid samples has identified the presence of commensal microorganisms. [Extracted from the article]

The leave-one-out cross-validation is an important parameter selection strategy for SVM-like family, including SVM and SVR. However, due to the high computational complexity, the adaptability of this strategy is restricted. In this paper, aiming at its practical application, a fast leave-one-out cross-validation method by using an adjustment factor is proposed which focusses especially on the practicability for the SVM-like family where the decision function can be expressed by explicit dot-product of each training sample pair. The ability of the proposed method in fast parameter selection is better than that of original leave-one-out cross-validation with the same or comparable learning performance. The simulation results indicate the effectiveness and speedup of the proposed leave-one-out cross-validation method. [ABSTRACT FROM AUTHOR]

Multiple source transfer learning (MSTL) has been obtaining more and more applications especially from several related source domains to help the learning task on target domain. However, multiple source transfer learning algorithms often deal with the corresponding quadratic programming problems which may suffer a big computational burden caused by the kernel matrix computation. In this paper, a novel common-decision-vector based multiple source transfer classification learning (CDV-MSTL) is proposed which doesn't depend on the intrinsic structure of data. This algorithm is based on the structural risk minimization principle and the SVM like framework, so it has good adaptability and better accuracy. Based on the theory of CVM, CDV-MSTL is extended to its CVM based version which can realize fast training for large scale data. Extensive experiments on synthetic and real-world datasets demonstrate the significant improvement in classification performance obtained by the proposed algorithm over existing MSTL algorithm. [ABSTRACT FROM AUTHOR]

Carbon quantum dots/TiO2 nanotubes composites were prepared by a simple technical route through which TiO2 nanotubes prepared by electrospinning were dispersed in carbon quantum dots solution, and dried at 80 °C. The results indicated that the TiO2 nanotubes composites were combined with the carbon quantum dots. The photocatalytic activity of the carbon quantum dots/TiO2 nanotubes composites was investigated by the degradation of rhodamine B under visible light irradiation, and it was demonstrated to be significantly enhanced compared with that of pure TiO2 nanotubes. Through analysis, this enhancement of visible light photocatalytic activity was attributed to the carbon quantum dots with the unique up-converted photoluminescence behavior. [ABSTRACT FROM AUTHOR]

The processes of decentralization, marketization, and globalization of socioeconomic reform in the last few decades have promoted the transformation of local governance in China. City marketing has become one of the most typical local governance activities. This article examines the mechanism of city marketing and urban scaling-up in Xuyi County, which is marketed as “Lobster Capital” for its lobster production and festival, from urban awareness, economy, and governance. It argues that the effective combination of city marketing and local resource endowment is a very important tactic for the development of small- and medium-sized cities. The key point in this combination is the branding of local production. Moving from city marketing to city branding means not only a long-term development strategy but also an endogenous development model. Rather than simply focusing on attracting capital, continuous city marketing based on endogenous sources of power, such as political, economic, and cultural power, can effectively integrate local resource endowment to overcome the shortcomings of externality and the short-term nature of single city marketing and maximize the social benefit of city marketing, which will in the end promote the urban reputation and economic growth. Hence, the continuous city marketing mode can express the urban ability and actual strength in a clearer and better way. Local government and its effective governance system is the core of city marketing, in which the main governor’s impact plays a particularly important role. This is a typical pro-growth model of urban governance in China. This article uses Xuyi as the case of continuous city market to analyze the success of a reasonable local endogenous governance system promoted by the main governor through taking full advantage of local resources. [ABSTRACT FROM PUBLISHER]

Little is known about the seasonal heterogeneity of land surface temperature (LST) and the interaction relationship between potential drivers in Sichuan Basin, China. In this study, based on exploring the spatial heterogeneity of LST in Sichuan Basin, China, multi-source remote sensing data as potential drivers were selected and a Geo-detector model was applied to analyze the main drivers and the interactive relationship between drivers on LST during different seasons. The results showed that the high-temperature areas in Sichuan Basin in different seasons all appeared in the cities near the high mountains on the edge of the basin. This phenomenon was summarized as "sinking heat island" by us. From the driving factors, the biophysical parameters (DEM, SLOPE and NDVI) had the greatest impact on LST in each season, reaching the peak in the transition season. The climate parameters (WIND, HUM, PRE and TEM) and socioeconomic parameters (LIGHT, POP and ROAD) also had a certain impact on LST. The influence of a single landscape parameter (SHDI, PD, LPI, ED and LSI) on LST is limited. From the effect of factor interaction on LST, the interaction of biophysical parameters, climatic parameters and landscape parameters from summer to the transitional season was strengthened obviously, and it showed a downward trend in the winter; in contrast, the socioeconomic parameters showed the opposite characteristics, indicating that the interaction between human activities and other factors affected LST more obviously in the winter. The results of this study are not only valuable for understanding the spatial features of LST but also important for formulating mitigation strategies and sustainable development of urban heat island in Sichuan Basin. [ABSTRACT FROM AUTHOR]

Rapid urbanization development and construction has seriously threatened the connectivity of habitat patches in cities and hindered the construction of ecological networks in highly urbanized areas. Among them, China is affected by early compressed urbanization, and the broken ecological space in cities and towns has attracted the extensive interest of researchers. To avoid the subjective randomness and single analysis of ecological space in urbanization areas, this paper takes the central urban area of Wuhan as the main research area. It comprehensively evaluates the ecological network space by combining the MSPA-MCR model. The main conclusions are as follows: (1) Identifying the ecological landscape types with important ecological significance in the study area: Core (88.29%), Islet (0.25%), Perf (0.63%), Edge (9.74%), Loop (0.22%), and Bridge (0.14%). Through the dPC landscape index, seven important ecological sources south of the middle reaches of the Yangtze River were identified. (2) According to the comprehensive factors of natural and human factors constructed by the MCR model, the minimum cumulative ecological resistance surface was established, with an average value of 2.65, a maximum value of 4.70, and a minimum value of 1.00, showing a trend that the ecological resistance values in the central and eastern parts are lower than those in the western part. (3) According to the standard deviation ellipse, the distribution direction of NE–SW in ecological sources was analyzed. The ecological sources distributed in the north were less, and the spatial distribution was scattered on the whole. The strong global positive correlation and local spatial aggregation characteristics of ecological resistance surface were evaluated according to spatial autocorrelation. Based on the gravity model, the interaction intensity of ecological corridors between source areas was evaluated, and the importance of ecological corridor protection and restoration was quantitatively analyzed. The research results provide scientific and reasonable references and a basis for ecological planning of Wuhan central city. [ABSTRACT FROM AUTHOR]

Over the past two decades in China, stress on the environment has increased continuously. This paper will assess the change in environmental quality over time, and its spatial variation using data from the statistical yearbooks of 31 provincial administrative regions in 1990, 1995, 2000, 2005, and 2010. These books provide a general assessment of the environment at the provincial level, and the three major economic regions from western to eastern China. By using the geographic information system (GIS) and SPSS, we analyzed the changing trend of China's eco-environment and calculated the changing trajectory in the gravity center of the eco-environmental quality. We conclude the following. (1) From 1990 to 2010, the rate of deterioration of the environment went down. We argue that the cause of this trend was neither the result as 'the deterioration trend was under control' noticed by the government departments concerned, nor 'the deterioration rate of the environment was increasingly intensified' suggested by many researchers. (2) Since 1990, the general environment has been worsening in China, but it was improved in some regions; however, the ecological deficit is still expanding and will last for a long time. (3) From western to eastern China, the deterioration rate of environmental quality was slowed down. The reasons include a good natural environment, a developed regional economy, and technology and finance in eastern China. (4) After extensive economic development in China, there are imbalances of population, economy, society, and the environment in the 31 provincial regions. The governments at all levels should play an important role in research and protecting the environment. In addition, it is imperative to implement positive measures such as controlling population, improving the environment, and promoting smart development to balance the socio-ecological system. [ABSTRACT FROM AUTHOR]

Composite additives have an important influence on the process of metal electrodeposition and the quality of a metal deposited layer. In this work, the additive thiourea (TU) was compounded with cetyltrimethyl ammonium chloride (CTAC), sodium dodecyl sulfate (SDS) and polyethylene glycol 20,000 (PEG20000), and their effect on the cyclic voltammetric behavior, electrochemical nucleation mechanism, crystallographic orientations and surface morphology of the nickel electrodeposition in ammoniacal solution were experimentally investigated. The results show that the introduction of composite additives resulted in a stronger cathodic polarization and increased the nucleation overpotential (NOP) values significantly, which had an important impact on forming compact and smooth nickel deposits. The chronoamperometry analysis indicated that the reduction in nickel followed the 3D progressive nucleation mechanism in the presence of composite additives at the step potential of −1.16 V and −1.18 V. Smoother and finer nickel films were found using scanning electron microscopy (SEM) images as the composite additives were used. X-ray diffraction revealed that all nickel deposit samples had the face-centered cubic structure, and five main crystal planes were displayed by the presence of composite additives in the electrolyte. Furthermore, the diffraction peaks of (111) and (200) crystal planes were slightly shifted toward lower 2θ values when thiourea was used in combination with additive CTAC or PEG20000. These results were beneficial for understanding the mechanisms and facilitating the rational design of additives for metal nickel electrodeposition. [ABSTRACT FROM AUTHOR]

This paper investigates the dynamic event-triggered predictive control problem of interval type-2 (IT2) fuzzy systems with imperfect premise matching. First, an IT2 fuzzy systems model is proposed, including a dynamic event-triggered mechanism, which can save limited network resources by reducing the number of data packets transmitted, and a predictive controller, which can predict the state of the system between the two successful transmitted instants to deal with unreliable communication networks. Then, according to the Lyapunov stability theory and imperfect premise matching method, sufficient conditions for system stabilization and the controller gain are obtained. Finally, the validity of the proposed method is demonstrated by the numerical examples. [ABSTRACT FROM AUTHOR]

ZHANG J. and WU F. (2006) China's changing economic governance: administrative annexation and the reorganization of local governments in the Yangtze River Delta, Regional Studies40, 3–21. In the course of Chinese economic and social transition, urban and regional development is faced with more competition. Against this backdrop, regional governance is undergoing challenge and change. Whilst change in the relationship between central and local governments has been the subject of study, one major change that has been neglected, despite its great importance, occurs among the different levels of local government within the same region. This paper studies the relationships among different local governments from the perspective of administrative annexation. It describes the conflict that has occurred in the Yangtze River Delta because of the problem of administrative division as well as the large-scale annexations since 2000. Through analysis of the source of conflict between administrative divisions and the effects of administrative annexation, the paper aims to reveal the role of local governments in the economic transition, as well as changes in regional governance, which indicate that the intervention of local governments in the economy is being strengthened in new ways. It is believed that China's political and economic reform is taking a prudent path, and that the conflict between administrative divisions is in fact a reflection of the way the administrative system is incompatible with economic reform. However, administrative annexation has an impact on the traditional relationship between local governments, and thus further promotes the reform of regional governance. Regional governance, Administrative changes, Regional economies, Local government, China, Yangtze River Delta ZHANG J. and WU F. (2006) La gouvernance régionale changeante en Chine: l'annexion administrative et la réorganisation de l'administration locale dans le delta du Yangtze, Regional Studies40, 3–21. Au cours de la phase transitoire économique et sociale en Chine, l'aménagement du territoire affronte une concurrence plus acharnée. Sur ce fond, la gouvernance régionale subit des épreuves. Alors que la recherche a porté sur le changement du rapport entre les administrations centrale et locale, un changement majeur auquel on n'a fait aucune attention, en dépit de son importance incontestable, se produit aux niveaux différents de l'administration locale au sein d'une même région. Cet article cherche à étudier les rapports entre les administrations locales différentes du point de vue de l'annexion administrative. L'article présente le conflit qui s'est produit dans le delta du Yangtze à cause du problème de la séparation administrative aussi bien que les annexions à grande échelle qui se sont produites depuis l'an 2000. A partir d'une analayse de la source du conflit entre les services administratifs et les effets de l'annexion administrative, l'article cherche à mettre en lumière le rôle des administrations locales dans la phase transitoire économique, aussi bien que les changements de la gouvernance régionale, qui laissent voir que l'intervention des administrations locales dans l'économie se renforce dans de nouvelles manières. On croit que la réforme économique et politique de la Chine s'engage sur une voie très empruntée, et que le conflit entre les services administratifs s'avère un reflet de la façon dont le système administratif est in𝜌conciliable avec la réforme économique. Toujours est-il que l'annexion administrative influe sur le rapport traditionnel entre les administrations locales et, par la suite, encourage davantage la réforme de la gouvernance régionale. Gouvernance régionale, Changements administratifs, Economies régionales, Administration locale, Chine Delta du Yangtze ZHANG J. and WU F. (2006) Veränderungen in der Regionalverwaltung Chinas: Angliederung zu Verwaltungszwecken und Umorganisation bei Kreisverwaltungen im Yangtze Delta, Regional Studies40, 3–21. Im Zuge des wirtschaftlichen und gesellschaftlichen Übergangs Chinas sind auch städtische und regionale Entwicklung verstärktem Wettbewerb ausgesetzt. Herausforderung und Wandel der Kreisverwaltung spielen sich vor diesem Hintergrund ab. Während Veränderungen in der Beziehung zwischen überregionalen und regionalen Verwaltungen Gegenstand wissenschaftlicher Untersuchungen gewesen sind, hat man eine Hauptveränderung trotz ihrer großen Bedeutung übersehen, obschon sie auf verschiedenen Ebenen der Ortsverwaltung innerhalb ein- und derselben Region auftritt. Dieser Aufsatz untersucht die Beziehungen zwischen verschiedenen Kreisverwaltungen aus der Perspektive der Verwaltungsangliederung. Der Aufsatz beschreibt den Konflikt, der sich seit dem Jahre 2000 im Yangtzedelta aus dem Problem der Verwaltungsteilung bei gleichzeitigen unfangreichen Angliederungen ergeben hat. Mit Hilfe einer Analyse der Ursache des Konfliktes zwischen Verwaltungsteilungen und Auswirkungen von Verwaltungsangliederung sucht dieser Aufsatz, die Rolle der Kreisverwaltungen sowohl beim wirtschaftlichen Übergang wie auch bei Veränderungen der regionalen Regierungsform zu erhellen, die darauf hinweisen, daß das Eingreifen der Kreisverwaltung in die Wirtschaft auf neue Art und Weise bestärkt wird. Man nimmt an, daß Chinas politische und wirtschaftliche Reform umsichtig gehandhabt wird, und daß der Konflikt zwischen Verwaltungsabteilungen in Wirklichkeit ein Licht auf die Unvereinbarkeit des Verwaltungssystems mit der Wirtschaftsreform wirft. Die Verwaltungsangliederung wirkt sich jedoch auf die traditionelle Beziehung zwischen Kreisverwaltungen aus, und bestärkt damit die Reform der Kreisverwaltung noch weiter. Regionalverwaltung, Umorganisation der Verwaltung, Regionalwirtschaften, China, Yangtzedelta ZHANG J. and WU F. (2006) Cambios en la gobernanza regional de China: Anexión administrativa y reorganización de gobiernos locales en el delta del río Yangtze, Regional Studies40, 3–21. En el transcurso de la transición económica y social de China, el desarrollo urbano y regional tiene ante sí el reto de una alta competencia. Con este fondo, el Gobierno regional está experimentando nuevos desafíos y transformaciones. Aunque los cambios ocurridos en la relaciones entre los gobiernos centrales y locales han sido objetos de estudio, se ha ignorado un cambio fundamental pese a ser de suma importancia: el cambio que se da entre los diferentes niveles de gobierno local en la misma región. En este ensayo se estudian las relaciones entre los diferentes gobiernos locales desde la perspectiva de la anexión administrativa. Describimos el conflicto que ha ocurrido en el delta del río Yangtze debido al problema de divisiones administrativas así como las anexiones a gran escala desde 2000. Analizando la fuente del conflicto entre las divisiones administrativas y los efectos de la anexión administrativa, con este ensayo pretendemos destacar la función de los gobiernos locales en la transición económica, así como los cambios de gobernanza regional. Estos cambios indican que la intervención de gobiernos locales en la economía se refuerza a través de nuevos métodos. Se cree que la reforma política y económica llevada a cabo en China está tomando una vía prudente y que el conflicto entre las divisiones administrativas reflejan claramente que el sistema administrativo es incompatible con la reforma económica. No obstante, la anexión administrativa ha hecho mella en la relación tradicional entre los gobiernos locales y, por consiguiente, fomenta la reforma del gobierno regional. Gobernanza regional, Cambios administrativos, Economías regionales, Gobierno local, China, Delta del río Yangtze [ABSTRACT FROM AUTHOR]

The global outbreak of the COVID-19 epidemic has caused a considerable impact on humans, which expresses the urgency and importance of studying its impacts. Previous studies either frequently use aggregated research methods of statistic data or stay during COVID-19. The afterward impacts of COVID-19 on human behaviors need to be explored further. This article carries out a non-aggregated study methodology in human geography based on big data from social media comments and takes Nanjing, China, as the research case to explore the afterward impact of the COVID-19 epidemic on the spatial behavior of urban tourists. Precisely, we propose the methodology covers two main aspects regarding travel contact trajectory and spatial trajectory. In contact trajectory, we explore three indicators—Connection Strength, Degree Centrality, and Betweenness Centrality—of the collected attractions. Then, in spatial trajectory, we input the results from contact trajectory into ArcGIS by using the Orientation–Destination Model and Standard Deviation Ellipse to explore the influences on the spatial pattern. By setting up comparative groups for the three periods of before, during, and after the COVID-19 in Nanjing, this study found that, in the post-epidemic era, (1) the spatial behavior of urban tourists showed a state of overall contraction; (2) the objects of contraction changed from urban architectural attractions to urban natural attractions; (3) the form of contraction presents concentric circles with the central city (Old City of Nanjing) as the core; (4) the direction of contraction heads to the large-scale natural landscape in the central city, which highlights the importance of green open spaces in the post-epidemic era. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of adaptive event-triggered synchronization for uncertain FNNs subject to double deception attacks and time-varying delay. During network transmission, a practical deception attack phenomenon in FNNs should be considered; that is, we investigated the situation in which the attack occurs via both communication channels, from S-C and from C-A simultaneously, rather than considering only one, as in many papers; and the double attacks are described by high-level Markov processes rather than simple random variables. To further reduce network load, an advanced AETS with an adaptive threshold coefficient was first used in FNNs to deal with deception attacks. Moreover, given the engineering background, uncertain parameters and time-varying delay were also considered, and a feedback control scheme was adopted. Based on the above, a unique closed-loop synchronization error system was constructed. Sufficient conditions that guarantee the stability of the closed-loop system are ensured by the Lyapunov-Krasovskii functional method. Finally, a numerical example is presented to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Even though the study of urban sociology in China is just a beginning, it doesn't mean that urban social problems in China are new or simple. As a very sensitive field, urban residential community has not been deeply analysed before owing to various reasons. This article tries to start with the background of China's social development and analyse the pattern, essence and evolution direction of China's urban residential community which is in the course of transfer of social pattern. This article first analyzes the functional mechanism of seven main elements affecting Chinese urban residential community in the course of transfer of social pattern. Some of the elements come into being under the social economic background, with Chinese characteristics, and have a profound influence on urban residential community. Based on that, the author then respectively infers the evolution of four main patterns of urban residential communities in China now. Finally, it puts forward the basic principles of urban community development in the current transfer period in China, and with a development eyesight, it makes a summary of the general characteristics of the Chinese urban residential community in the future. [ABSTRACT FROM AUTHOR]

Social Media Big Data (SMBD) is widely used to serve the economic and social development of human beings. However, as a young research and practice field, the understanding of SMBD in academia is not enough and needs to be supplemented. This paper took Web of Science (WoS) core collection as the data source, and used traditional statistical methods and CiteSpace software to carry out the scientometrics analysis of SMBD, which showed the research status, hotspots and trends in this field. The results showed that: (1) More and more attention has been paid to SMBD research in academia, and the number of journals published has been increased in recent years, mainly in subjects such as Computer Science Engineering and Telecommunications. The results were published primarily in IEEE Access Sustainability and Future Generation Computer Systems the International Journal of eScience and so on; (2) In terms of contributions, China, the United States, the United Kingdom and other countries (regions) have published the most papers in SMBD, high-yield institutions also mainly from these countries (regions). There were already some excellent teams in the field, such as the Wanggen Wan team at Shanghai University and Haoran Xie team from City University of Hong Kong; (3) we studied the hotspots of SMBD in recent years, and realized the summary of the frontier of SMBD based on the keywords and co-citation literature, including the deep excavation and construction of social media technology, the reflection and concerns about the rapid development of social media, and the role of SMBD in solving human social development problems. These studies could provide values and references for SMBD researchers to understand the research status, hotspots and trends in this field. [ABSTRACT FROM AUTHOR]

We describe lightweight three-dimensional (3D) graphene hybrid SiO2 aerogels (GSAs) with hierarchically robust interconnected networks fabricated via an in situ deposition procedure after a hydrothermal assembling strategy with graphene oxide sheets. The nano-/micron-thick SiO2 coating conformably grew over porous graphene templates with two constituents (e.g., graphene and SiO2) and formed chemically bonded interfaces. In addition, it significantly refined the primary graphene pores by hundreds of microns into smaller porous patterns. Studies of its mechanical properties verified that the graphene interframework made the ceramic composites elastic, while SiO2 deposition enhanced the strength required it to resist deformation. The higher SiO2 contents resulted in lower elasticity but larger strength because of the apparent nanosize effect of SiO2 ceramic thickness; GSAs with a density of 82.3–250.3 mg/cm3 (corresponding to SiO2 sol with concentration ranging from 5 to 20 wt %) could reach a good balance of strength and elasticity. Benefiting from hierarchical micronetworks consisting of semiclosed or closed pores, GSAs offer excellent thermal-insulation performance, with thermal conductivity as low as 0.026 W/(m·K). GSAs offer improved fire-resistant capacity rather than that of pure carbon-based aerogels via the synergic protection of SiO2 ceramic accretion. This highlights the promising applications of GSAs as lightweight thermal-shielding candidates for industrial equipment, civil architectures, and defense transportation vehicles. [ABSTRACT FROM AUTHOR]