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Highlights Nonflammable gel polymer electrolyte (SGPE) is developed by in situ polymerizing trifluoroethyl methacrylate (TFMA) monomers with flame-retardant triethyl phosphate (TEP) solvents and LiTFSI–LiDFOB dual lithium salts. Molecular polarity interaction between TEP and PTFMA mitigates interfacial reactions and changes the solvation of Li+. SGPE forms stable inorganic-rich solid electrolyte interface/cathode electrolyte interface layer, exhibiting well compatibility with Li anode and LiCoO2-type high-voltage cathode.

Abstract Lithium metal solid‐state battery is the first choice of batteries for electromobiles and consumer electronic products because of the specific capacity of 3860 mAh g−1 and high electrochemical potential (−3.04 V) of Li metal. Flexible polymer solid electrolytes have become the optimal solution to produce high energy density lithium batteries with arbitrary size and shape. In this work, we introduce a halide perovskite, CsSnI3, into the polyethylene oxide/lithium bis‐(trifluoromethanesuphone)imide (PEO–LiTFSI) polymer matrix. The CsSnI3 could form a LixSn alloy with Li, leading to homogenization of the electric field and Li+‐flux at the interface, Sn atom also bonds with the TFSI− anion to provide more dissociated Li+. Besides that, the I atom could interact with Li to form an electronic insulation with a strong blocking effect on electron tunneling. As a proof of concept, the synergy mechanism of the PEO–LiTFSI–CsSnI3 electrolyte improves the stable cycle life of the symmetric battery to more than 500 h, and the Li+ conductivity raised to 6.1 × 10−4 S cm−1 at 60°C. The application of the “zwitter ions analog” halide perovskite in PEO–LiTFSI provides a new choice among various methods to improve the electrochemical performance of polymer solid‐state batteries.

Abstract Social integration, a huge issue triggered by migration, leads to potential social fragmentation and confrontation. Focusing on the precise enhancement of "inner" subjective social integration is the ultimate urbanization solution to enhance people-centered well-being and promote full social integration. This article used data from the China Migrants Dynamic Survey 2017 (CMDS 2017) to reveal the spatial patterns and mechanisms of subjective social integration in Chinese cities. We make an innovative attempt to introduce multiscale geographically weighted regression (MGWR) to address the appropriateness of policy formulation by addressing the spatial variation in the factors. The results demonstrate that the influences on subjective social integration have a strong spatial heterogeneity in China, a vast and unevenly developed country. Expanding on the typical factors, household registration and political participation affect North China more than other regions; and housing and marriage have a greater impact in South China, especially in the Pearl River Delta and the Eastern Seaboard. Income, welfare, and healthcare are indiscriminately sweeping through most of China. Such a conclusion reminds the Chinese government that it needs to consider not only addressing some of the national constraints to subjective social integration but also imposing precise, site-specific changes for different regions.

Abstract The optimization of railway construction schemes is a complexity system engineering task with multiple dimensions, diverse conditional constraints, and multifaceted objective assessments. The decision-making and scheme evaluation entail subjectivity, randomness, and fuzziness. To address the comprehensive optimization challenge in construction schemes effectively and efficiently, we investigate an optimization method for railway construction schemes. This method is based on multi-dimensional combination weighting and improved grey theory. After analyzing the primary influencing factors, we established a railway construction plan optimization index system comprising 4 dimensions and 18 factors. The weight combination coefficient is determined using the pros and cons solution distance method, and the optimal weight set for the index is determined through the multi-dimensional combination weighting approach. Utilizing the method of superior and inferior solution distance coupled with grey theory, we ascertain the order of advantages and disadvantages for each construction scheme, subsequently achieving construction scheme optimization. To illustrate this, we employ the optimization process for a high-speed railway section in Guangxi as an exemplar. The verification results indicate that the gray relative closeness values for schemes A, B, and C are 0.7089, 0.4813, and 0.4463, respectively. Scheme A has the highest gray relative closeness value, thus making it the optimal route scheme. The optimal results obtained through this method align with the outcomes of expert validation and existing research, thereby validating the effectiveness and practicality of the model. By employing a multidimensional combination weighting method, the deficiencies of traditional indicator weight calculations are mitigated, resulting in indicator weights that are more reflective of the actual circumstances. At the same time, the application of improvements in the grey theory comprehensive evaluation method enables the integration and computation of indicator data for each construction plan. Through the intuitive representation of grey relative closeness, the advantages and disadvantages of each plan are effectively characterized. This enhances the scientific rigor and applicability of the railway construction plan optimization process. The research findings can serve as a reference for similar railway construction scheme selection problems in the future.

Lithium–oxygen batteries (LOBs) have extensive applications because of their ultra-high energy densities. However, the practical application of LOBs is limited by several factors, such as a high overpotential, poor cycle stability, and limited rate capacity. In this paper, we describe the successful uniform loading of Mn3O4 nanoparticles onto multi-walled carbon nanotubes (Mn3O4@CNT). CNTs form a conductive network and expose numerous catalytically active sites, and the one-dimensional porous structure provides a convenient channel for the transmission of Li+ and O2 in LOBs. The electronic conductivity and electrocatalytic activity of Mn3O4@CNT are significantly better than those of MnO@CNT because of the inherent driving force facilitating charge transfer between different valence metal ions. Therefore, the Mn3O4@CNT cathode obtains a low overpotential (0.76 V at a limited capacity of 1000 mAh g−1), high initial discharge capacity (16895 mAh g−1 at 200 mA g−1), and long cycle life (97 cycles at 200 mA g−1). This study provides evidence that transition metal oxides with mixed-valence states are suitable for application as efficient cathodes for LOBs.

Abstract Objective To identify the risk factors for moderate and severe contrast media extravasation and provide effective guidance to reduce the degree of extravasation injuries. Methods We observed 224 adult patients who underwent contrast media extravasation at Xiangya Hospital of Central South University, Hunan Provincial Maternal and Child Healthcare Hospital, and Xiangya Changde Hospital, Hunan Province between January 1, 2018 and December 31, 2022. Risk factors for moderate extravasation injuries were evaluated using univariate and multivariate logistic regression. Results Among 224 patients, 0 (0%) had severe, 18 (8.0%) had moderate, and 206 (92.0%) had mild contrast media extravasation injury. Multivariate logistic regression analysis revealed malignant tumors (odds ratio [OR] = 6.992, 95% confidence interval [CI]: 1.674–29.208), Iohexol (OR = 9.343, 95% CI 1.280–68.214), large-volume (> 50 mL) extravasation (OR = 5.773, 95% CI 1.350‒24.695), and injection site (back of the hand) (OR = 13.491, 95% CI 3.056–59.560) as independent risk factors for moderate injury. Conclusion Risk factors for moderate contrast media extravasation injury are malignant tumors, iohexol, large-volume (> 50 mL) extravasation, and back-of-the-hand injection. Analysis of these risk factors can help reduce the degree of injury after extravasation. Clinical relevance statement High-risk patients with extravasation support should choose the appropriate contrast media type, avoiding back-of-the-hand injections. We recommend that patients with cancer be implanted with a high-pressure resistant central venous catheter and receive effective measures to timely detect and reduce extravasation.

Selenium has high theoretical volumetric capacity of 3253 mAh cm−3 and acceptable electronic conductivity of 1 × 10−5 S m−1, which is considered as a potential alternative to sulfur cathode for all-solid-state rechargeable batteries with high energy density. However, the development of all-solid-state Li–Se batteries (ASSLSBs) are hindered by sluggish kinetics and poor cycling life. In this work, trigonal Se nanocrystallines are homogenously distributed in the interspace and on the surface of MXene layers (denoted as Se@MXene composite) by a novel melt-diffusion method. ASSLSBs based on this Se@MXene composite cathode exhibit large specific capacity of 632 mAh g−1 at 0.05 A g−1, high-rate capability over 4 A g−1, and excellent cycling stability over 300 cycles at 1 A g−1. The ex-situ analytical techniques demonstrate that the excellent electrochemical performance of Se@MXene cathode largely arises from structural stability with the assistance of conductive MXene and reversible redox behavior between Li2Se and Se during the repeating charge/discharge process. Our study points out the potential of material design of Se cathode based on conducting 2D materials with good electrochemical behavior, which may accelerate the practicability of ASSLSBs.

Breaking the limitations of the urban perspective, there is an urgent need to study the influence of the village environment on the willingness of rural households to resettle. This paper explored the determinants and the mechanism of village environment factors on resettlement willingness using full-sample survey data (872,414 households) of 1382 administrative villages in Huai'an, a typical agricultural area in Eastern China. The result revealed that environmental factors generally have a greater impact on the spatial heterogeneity of resettlement willingness, in the order of natural environment, economic environment, social environment, and policy environment; among which geographic location, housing conditions, behavioral tendency of farmers and planning guidance are the key factors. In addition, the absolute location of the urban area in the geographic region has a significantly greater effect than that of the county, and the "following behavior" of the farmers affected their resettlement decision. Therefore, differentiated policies should be formulated according to the spatial distribution of the resettlement willingness, building a dual-core village and town system within the county.

Silicon (Si) anodes with extremely high theoretical capacities are considered indispensable for next-generation high-energy lithium-ion batteries (LIBs). However, several intractable problems, including pulverization, poor electrical contact, and continuous side reactions caused by the large volume change of Si during lithiation/delithiation, lead to a short cycle life and poor rate capability, thus hindering the commercial use of Si anodes in LIBs. Two-dimensional (2D) Si with a unique graphene-like structure has a short ion diffusion pathway, small volume change during lithiation, and efficient redox site utilization, making it more promising than bulk Si or Si with other versatile structures for use in LIBs. Theoretical analysis demonstrated that the low energy barrier on the surface of 2D Si accelerates the transport of Li+. However, the issues surrounding 2D Si, including the tedious and user-unfriendly synthesis, ease of restacking, and atmospheric sensitivity, limit its practical applications, which are discussed in this review. Furthermore, possible solutions to these remaining challenges and new directions are provided, with the aim of designing practical and high-performance 2D Si anodes for next-generation LIBs.

Developing highly conductive, stable, and active hydrogen evolution reaction (HER) catalysts is a critical step towards establishing the hydrogen economy. However, there are few catalysts, except for noble metals, that can meet all the requirements. Recently, two-dimensional (2D) transition metal carbon/nitride (MXene) materials have shown excellent performance in catalysis, and have attracted wide attention from researchers. In this study, the effectiveness of non-metal element (B, C, N, P, and S)-doped Ti3C2O2 MXene in the electrocatalytic hydrogen evolution reaction was investigated using density functional theory (DFT) calculations. Non-metal atoms as electron donors can provide additional electrons to the O functional group on the catalyst surface, thereby reducing charge transfer from H to O and the interaction between H and O. The Gibbs free energy (∆GH) of non-metal element-doped Ti3C2O2 is closer to 0 than that of pristine Ti3C2O2, demonstrating better hydrogen evolution performance. Furthermore, in the hydrogen evolution path, the desorption process is more inclined to the Heyrovsky mechanism, and doping greatly reduces the energy barrier of the reaction, thereby improving the catalytic efficiency. The present results prove that doping with non-metallic elements is an effective means of improving the catalytic activity of Ti3C2O2 for hydrogen evolution.

The accumulation of sand on desert roads poses a significant threat to the smooth transportation and driving safety of these roads. To address this issue, a combined approach using the variable weight theory and cloud model theory is proposed for conducting a safety risk assessment of sand accumulation on desert roads. An evaluation index system for sand accumulation hazards is obtained through the analysis of regional geomorphological conditions, wind dynamic conditions, and engineering design factors. The evaluation index system’s constant weights are determined using the Five-Point Scale Method and Analytic Hierarchy Process. Moreover, the Variable Weight Theory is used to optimize these weights based on the actual state of the project, thereby enhancing the accuracy of risk assessment. Finally, based on the cloud model theory, a safety risk assessment model is constructed for sand accumulation hazards on desert highways. The sand accumulation hazard level of the highway is determined through this model, and the comprehensive evaluation results are visualized and presented intuitively using the MATLAB software. The experimental section of the new Wuhai-Maqin expressway sand prevention test is taken as an example for practical verification. The results show that the sand accumulation disaster level of the experimental section is grade Ⅲ, which is basically consistent with the actual engineering situation, verifying the reliability and applicability of the model. Therefore, this model could serve as an essential reference for risk assessments of sand accumulation hazards, location optimization selection, and the establishment of effective sand prevention engineering measures for desert highways.

In the context of China’s New Urbanization Strategy, a growing number of cities are beginning to experience significant changes in their intra-city structure and size distribution, but systematic research is still lacking. This paper investigated the intra city-size distribution of 214 cities in China’s Yangtze River Delta Region (YRDR) from 1990 to 2020. The study used the Pareto index to portray the equalization differences in intra city-size distribution, and investigated the heterogeneity of its influencing factors using multiscale geographically weighted regression (MGWR). The results showed that most of the cities in the YRDR had a city-size distribution consistent with a Pareto distribution but still tended to be polarized. Among them, the better-developed large cities and regions were more consistent with the Zipf distribution, as were the county-level cities and prefecture-level cities. In terms of spatio-temporal distribution, the intra city-size distribution showed a spatial agglomeration pattern of “polarization in the west and equalization in the east” and the scope and intensity of cold and hot spots reduced. Regarding driving factors, land, industry, and population were essential influences on the intra city-size distribution. Of these, the natural environment and location were important global influencing factors, and economic and social factors only had a more significant influence in 1990 and 2020. The impact of industry restructuring gradually increased, and the population was a significant influence only in the early years. By exploring the intra city-size distribution, this paper provides a scientific basis for the optimization of town structure and policy formulation in small and medium-sized cities, and some new concerns have been proposed.

The MEMS gyroscope is one of the basic units of inertial navigation, whose performance and accuracy is noteworthy. Because of the limitations of processing technology and other factors, the relative manufacturing error of MEMS gyroscopes is usually large. Errors directly lead to a frequency mismatch of resonant structures and consequently restrict the performance improvement of the gyroscope. This study proposes a mechanical trimming technique combining the addition and removal of gold in a ring MEMS gyroscope. Firstly, the analysis of the gyroscope dynamics and error model and trimming theory provides theoretical guidance for the trimming process. Secondly, the method of adjusting the mass is investigated, and the ablation threshold of femtosecond laser parameters on gold is analyzed, which provides the process with parameters for the trimming experiment. Finally, the frequency trimming process is conducted in three steps, including the addition of gold spheres and the removal of gold spheres and gold film, which are applicable to the trimming process at different rates of frequency split. The results shows that the proposed method can reduce the frequency split of the gyroscope from 4.36 to 0.017 Hz.

Vascular smooth muscle cells (VSMCs) are critical elements of the vascular wall and play a crucial role in the genesis and development of atherosclerosis (AS). Increasingly, studies have indicated that long noncoding RNAs (lncRNAs) regulate VSMC proliferation, apoptosis, and other biological processes. Nevertheless, the role of lncRNA NFIA-AS1 (hereinafter referred to as NFIA-AS1) in VSMCs and AS remains unclear. Quantitative real-time PCR (qRT-PCR) was performed to analyze the messenger RNA (mRNA) levels of NFIA-AS1 and miR-125a-3p. CCK-8 and EdU staining were performed to detect VSMC proliferation. VSMC apoptosis was evaluated by flow cytometry. The expression of various proteins was detected using western blotting. The levels of inflammatory cytokines secreted by VSMCs were measured by enzyme linked immunosorbent assay (ELISA). The binding sites of NFIA-AS1 and miR-125a-3p, as well as miR-125a-3p and AKT1, were analyzed using bioinformatics methods and validated using a luciferase reporter assay. The function of NFIA-AS1/miR-125a-3p/AKT1 in VSMCs was clarified through loss- and gain-of-functional experiments. We confirmed that NFIA-AS1 was highly expressed in AS tissues and VSMCs induced by oxidized low-density lipoprotein (Ox-LDL). Knockdown of NFIA-AS1 restrained the exceptional growth of Ox-LDL-induced VSMCs, promoted their apoptosis, and decreased the secretion of inflammatory factors and expression of adhesion factors. In addition, NFIA-AS1 regulated the proliferation, apoptosis, and inflammatory response of VSMCs through the miR-125a-3p/AKT1 axis, suggesting that NFIA-AS1 may be a potential therapeutic target for AS.

Background/objective: Coronavirus disease 2019 (COVID-19) is a disaster in human medical history and glucocorticoids remain the most promising therapy. Osteonecrosis is a disease caused by reduced intraosseous blood flow to bones in the joints, which will rapidly induce joint destruction. Approximately one-third patients with severe acute respiratory syndrome (SARS) who received high cumulative doses and long treatment durations of glucocorticoids occurred osteonecrosis. Considering the similarity of SARS and COVID-19 on their pathogen, clinical characteristics, and therapeutic strategies, it is particularly desirable to investigate whether osteonecrosis will become a common sequela among convalescent COVID-19 patients. Methods: This multi-strategy study was designed by integrating different research methods, such as meta-analysis, systematic review, and cross-sectional investigations to address above study objectives. At first, two meta-analyses were performed on the osteonecrosis incidence among SARS patients and the clinical data of glucocorticoid exposure among COVID-19 patients. Then, a systematic review of low-dosage glucocorticoid associated osteonecrosis and a cross-sectional investigation of glucocorticoid exposure of COVID-19 patients in Wuhan city of China were also conducted. Moreover, the pathogenesis, diagnosis, prevention, and treatment options for osteonecrosis patients with COVID-19 infection were further presented and discussed. Results: Our meta-analysis showed that 32% of SARS patients had developed osteonecrosis after receiving glucocorticoid treatment with high dose, and our system review supported that low level glucocorticoid exposure might also lead to the occurrence of osteonecrosis. Similarly, 40% of COVID-19 patients had undergone glucocorticoid treatment according to our meta-analysis. The cross-sectional investigation in Wuhan city of China found that the average of cumulative glucocorticoid exposure level was 504 ​mg calculated by the dosage of methylprednisolone. Notably, a confirmed osteonecrosis case was identified from 1406 patients with COVID-19 during our cross-sectional investigation, implying that preventive management of osteonecrosis should be better started with regular clinical follow-up observation. Conclusion: Growing evidence of the glucocorticoid therapy for COVID-19 patients prompts us to establish risk-classification-based early screening and to introduce early prevention protocol of its associated osteonecrosis that will be of clinical significance in favor of improved prognosis of this disease. The translational potential of this article: To establish risk-classification-based early screening and to introduce early prevention protocol of glucocorticoid-induced osteonecrosis will be of clinical significance in favor of improved prognosis of COVID-19.

Abstract Background Plantaginis Semen has been widely used as folk medicine and health care food against hyperuricemia (HUA) and gout, but its pharmacological mechanism remains unclear. This study investigated the therapeutic mechanism of Plantaginis Semen extract on potassium oxonate -induced HUA rats based on a lipidomics approach. Methods A model of HUA was established by potassium oxonate intragastric administration. 42 Sprague-Dawley (SD) male rats were randomly divided into the control group, model group, benzbromarone group (10 mg/kg) and three Plantaginis Semen groups (n = 7). The Plantaginis Semen groups were treated orally with Plantaginis Semen, 0.9375, 1.875 or 3.75 g/kg for 28 days. The levels of serum uric acid (UA), creatinine (Cr), triacylglycerol (TG) and tumor necrosis factor-α (TNF-α) were measured using enzyme-linked immunosorbent assay kits. Ultra performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS) was used for the serum lipidomics analysis, multivariate statistical analysis and independent samples t-test were carried out for the pattern recognition and characteristic metabolites identification. The relative levels of critical regulatory factors were determined by quantitative real-time polymerase chain reaction (RT-qPCR). Results Compared with the model group, the levels of serum UA, Cr, TG and TNF-α were significantly (p

In the context of China’s New Urbanization Strategy, it is of great practical significance to study rural–urban population migration from the perspective of house purchases by rural households. In this paper, the Huai’an Rural Survey Dataset (872,414 households) was used to study the heterogeneity of rural households’ house purchases in different classes of urban destinations, and its influencing factors were analyzed with GeoDetector. The results show that the urban house purchase destinations preferred by farmers were county towns, townships, foreign cities, and metropolitan areas, indicating that in situ urbanization has become the main path of urbanization for farmers in Huai’an. Among the environmental influencing factors, the rural environment had the greatest influence on house purchases locally (in the township and county town), and this influence decreased with the outward shift of house purchase destinations. The housing environment, the settlement environment, and the population and family environment were the main environmental impact elements. The natural environment and the policy environment had little influence on the house-purchasing behavior of farmers, and the location environment was critical in exotic locations (metropolitan areas and foreign cities). Therefore, this paper argues that a higher demand for housing is growing in China’s less developed rural areas, creating a situation in which the metropolitan area is the core and the county town is the main contributor. In terms of policy improvements, it is important to pay more attention to small cities such as counties and to offer housing concessions and welfare to “new citizens” from rural areas, as well as to significantly improve the housing, earnings, and public service environment for those who prefer to stay in the countryside.

CRISPR-Cas systems are prokaryotic adaptive immunity against invading phages and plasmids. Phages have evolved diverse protein inhibitors of CRISPR-Cas systems, called anti-CRISPR (Acr) proteins, to neutralize this CRISPR machinery. In response, bacteria have co-evolved Cas variants to escape phage’s anti-CRISPR strategies, called anti-anti-CRISPR systems. Here we explore the anti-CRISPR allosteric inhibition and anti-anti-CRISPR rescue mechanisms between Streptococcus thermophilus Cas9 (St1Cas9) and the anti-CRISPR protein AcrIIA6 at the atomic level, by generating mutants of key residues in St1Cas9. Extensive unbiased molecular dynamics simulations show that the functional motions of St1Cas9 in the presence of AcrIIA6 differ substantially from those of St1Cas9 alone. AcrIIA6 binding triggers a shift of St1Cas9 conformational ensemble towards a less catalytically competent state; this state significantly compromises protospacer adjacent motif (PAM) recognition and nuclease activity by altering interdependently conformational dynamics and allosteric signals among nuclease domains, PAM-interacting (PI) regions, and AcrIIA6 binding motifs. Via in vitro DNA cleavage assays, we further elucidate the rescue mechanism of efficiently escaping AcrIIA6 inhibition harboring St1Cas9 triple mutations (G993K/K1008M/K1010E) in the PI domain and identify the evolutionary landscape of such mutational escape within species. Our results provide mechanistic insights into Acr proteins as natural brakes for the CRISPR-Cas systems and a promising potential for the design of allosteric Acr peptidomimetics.

A series of supported Ru based catalysts (support = AC, Al2O3, SiO2, HZSM-5) were prepared with different methods and applied in the hydrogenation of 2,2,4,4-tetramethyl-1,3-cyclobutanedione (CBDK) to 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO). Detailed catalyst characterizations of XRD, TEM, BET, ICP, XPS and NH3-TPD methods were applied to investigate the support effect and influence of preparation methods. Complete conversion of the substrate was achieved with the selectivity of CBDO up to 99.1% over Ru/AC catalysts. The superiority of Ru/AC catalyst prepared with chemical precipitation method over other counterparts were attributed to the larger specific surface area, smaller metal particle size and better Ru dispersion, which was more favorable for the hydrogenation of CBDK.

Influenza virus-caused lung infection and its pandemic outbreaks are a persistent public health challenge. The H1N1 subtype is the most common type of influenza infection observed in humans. Maxingshigantang decoction, a classic formula of Chinese herbal medicine, has been used for the prevention and treatment of respiratory infection for many centuries. Qingfeiyin decoction, based on Maxingshigantang, has been used in the clinic for decades. To explore the underlying mechanisms, according to the traditional Chinese medicine theory “the lung and the large intestine are interior–exterior,” which can be translated to the “gut–lung axis” in a contemporary term, the composition of gut microbiota was determined using 16S rRNA and the transcriptome of the colon was determined by RNA sequencing. The results showed that Qingfeiyin decoction decreased the viral load, alleviated the lung injury, increased the survival rate, partly restored the shortening of the colon caused by the H1N1 virus, and downregulated inflammatory pathways including MAPK, TNFα, and JAK-STAT signaling pathways. Qingfeiyin decoction increased the relative abundance of the genera of Coprococcus, Ruminococcus, Lactobacillus, and Prevotella and prevented the H1N1 virus-induced decrease in the abundance of the genera of Escherichia, Parabacteroides, Butyricimonas, and Anacrotruncus. These results will help better understand the mechanisms for Qingfeiyin decoction’s protective effect against influenza virus infection.

BackgroundAlthough congenital heart defect (CHD) was the dominating birth defect, the time trend analysis of CHD was largely unknown. In our study, the time trend analysis of CHD from 2005 to 2020 in Jinan was conducted, aimed to reveal the epidemiological characteristics in a city and provided the data basis for the government to make a policy intervention.MethodsA multi-institutional and retrospective review of CHD for all births from January 1, 2005 to December 31, 2020 was performed. Proportioner prevalence was used to describe the distribution of CHD. Comparisons of CHD characteristics among different groups were assessed with Chi-squares tests. Cochran-Armitage tests (CAT) were used to track changes in CHD prevalence.ResultsAbout 322,374 births and 5,180 CHD in Jinan were included from 2005 to 2020, and the total CHD prevalence was 3.92 per 1,000 births. The CHD prevalence showed an upward trend, with a total increase of 227.66% from 2005 to 2020. The CHD prevalence in urban areas was 34.17% higher than that in rural areas, but the gap was narrowing. Atrial septal defect (3.07 per 1,000 births), patent ductus arteriosus (1.62 per 1,000 births), ventricular septal defect (1.18 per 1,000 births), tetralogy of Fallot (0.62 per 1,000 births), and atrioventricular septal defect (0.47 per 1,000 births) were the 5 most common subtypes.ConclusionThe prevalence of CHD in Jinan was gradually on the rise, which needs to be highly focused on by the health management department. Older pregnant women and women in rural areas should be concerned, and targeted measures need to be introduced.

Abstract Background Matricaria recutita (German chamomile) and Chamaemelum nobile (Roman chamomile) belong to the botanical family Asteraceae. These two herbs are not only morphologically distinguishable, but their secondary metabolites – especially the essential oils present in flowers are also different, especially the terpenoids. The aim of this project was to preliminarily identify regulatory mechanisms in the terpenoid biosynthetic pathways that differ between German and Roman chamomile by performing comparative transcriptomic and metabolomic analyses. Results We determined the content of essential oils in disk florets and ray florets in these two chamomile species, and found that the terpenoid content in flowers of German chamomile is greater than that of Roman chamomile. In addition, a comparative RNA-seq analysis of German and Roman chamomile showed that 54% of genes shared > 75% sequence identity between the two species. In particular, more highly expressed DEGs (differentially expressed genes) and TF (transcription factor) genes, different regulation of CYPs (cytochrome P450 enzymes), and rapid evolution of downstream genes in the terpenoid biosynthetic pathway of German chamomile could be the main reasons to explain the differences in the types and levels of terpenoid compounds in these two species. In addition, a phylogenetic tree constructed from single copy genes showed that German chamomile and Roman chamomile are closely related to Chrysanthemum nankingense. Conclusion This work provides the first insights into terpenoid biosynthesis in two species of chamomile. The candidate unigenes related to terpenoid biosynthesis will be important in molecular breeding approaches to modulate the essential oil composition of Matricaria recutita and Chamaemelum nobile.

As a result of the continuous improvement in passengers’ requirements for the quality of train operation, the comfort of high-speed train operation has been paid increasing attention. The evaluation of comfort has gradually changed from the narrow sense of a comfort evaluation model containing only vibration to the generalized evaluation of passengers’ overall satisfaction with the ride environment of specific lines. The factors affecting comfort evaluation include physical, physiological, and psychological aspects. To address the problems that the existing comfort evaluation model has a single index and that the weight determination of some indicators is greatly affected by subjectivity, we built a high-speed train comfort evaluation model based on variable weight theory. Combined with the actual working conditions of the Baolan passenger dedicated line, dynamic detection data and noise monitoring data captured by a track inspection car were combined with a passenger ride comfort questionnaire survey. In addition, the initial weight value of each factor was optimized by constructing an equilibrium function to realize the balance between the various factors, so as to realize the comprehensive fuzzy evaluation of high-speed train comfort. The results show that the comprehensive evaluation result of the comfort degree of the high-speed train on the Tongwei to Lanzhou section of the Baolan passenger dedicated line has a grade of II. The fuzzy scores of the evaluations using variable weights and constant weights were analyzed from the perspective of membership degree. The variable weight optimization avoids the one-sidedness and extremeness of the constant weight calculation. The comprehensive evaluation results are closer to the real situation. The research results can provide a reference for the comfort evaluation of high-speed trains with extreme differences in state values and constant weights and help in the acquisition of more realistic evaluation results.

After the construction of desert highway, the physiognomy changes caused by surface wind erosion and accumulation not only seriously threaten the stability of road structure, but also have a tremendous impact on the safety of the highway operation and the maintenance work on the highway. The purpose of this paper is to explore the change of sand sedimentation and the law of sand transport along the highway in the moving dune areas, and to clarify the change of sand flow and the formation mechanism of sand damage in the moving dune areas. Taking the test section of Wuhai-Maqin Expressway in the hinterland of Tengger Desert as the research object, the on-site observation of sand accumulation and the recording of wind information by small weather stations were adopted, supplemented by CFD numerical simulation method, in order to provide reference for the construction of sand control system in moving dune areas. The study results show that: (1) Dunes not only obstruct wind-drift sand but are also the sediment source condition for forming road sand. The windward dunes near the road are affected by wind and the deposition of sand will quickly bury the road in the strong wind season. (2) Compared with highways with flat terrain, the existence of dunes affects the flow field structure and the distribution of sand sedimentation on the highway, in which, under the influence of the gathering effect, the flow velocity reaches the maximum at the top of the dune and a large low-speed recirculation zone is formed on the lee side of the dune, easily causing sand accumulation. (3) Sediment accumulates at the windward side of the embankment or dune where sandy air current is easy to saturate. However, with the increase of wind speed, in addition to the grit carried by the sandy air current itself, new sand rolled up on the windward side of the dunes also form deposits on the road surface and the amount of sand-accumulation on highway surface and leeward side tends to increase. As a result, for the highway in drifting sand dunes areas, sediment prevention and control measures should be taken actively. It is necessary to remove sediment from the road in time and reduce the moving speed of sand dunes and the deposition range of wind-sand flow, ultimately for the purpose of reducing the damage wind-sand activity causes to the highway in desert.

Ultrafast pulsed lasers can facilitate the manufacturing of complex microstructures. However, previous laser processing applications have focused on static components. Consequently, the application of laser processing in high-performance resonant structures has received less attention. Ultrafast lasers provide a unique opportunity for realizing the structure detachment from the planar fused silica substrates. However, the processing quality has a considerable influence on resonant structures. High-quality and high-efficiency laser manufacturing methods are critical for processing resonant structures. In this study, we demonstrate a method for processing fused silica microstructures based on the femtosecond laser. We studied the influence of different laser parameters on the processing quality and determined the optimal laser parameters suitable for the microstructure. The resonant structure of the butterfly gyroscope was used to verify the manufacturing method. A steepness of 86.6° and a roughness of 653.2 nm were achieved by using the optimized laser parameters. These are expected to provide technical support for the development of high-performance fused silica dynamic devices in the future.

Abstract Background Hyperuricemia as a metabolic disease is usually associated with lipid metabolic disorder. The purpose of this study is to identify potential lipid biomarkers and provide the evidence for the relationship between hyperuricemia and lipid-related diseases. Methods Lipidomics-a specialized study of lipid metabolites-has become a highly sensitive and powerful tool for biomarker discovery. In this work, an ultra-performance liquid chromatography-quadruole-time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS)-based on Lipidomics approach was employed to investigate serum samples from potassium oxonate-treated rats to find potential biomarkers. Principal component analysis (PCA) was used to analyze the MS data to assess the establishment of hyperuricemia model. Orthogonal partial least-squares discriminant analysis (OPLS-DA) in combination with independent samples t-test was performed for biomarker selection and identification. Results Thirteen potential biomarkers in rat serum were identified in the screen, and two abnormal metabolism pathways were found, namely glycerolphospholipid metabolism and glycosylphosphatidylinositol-anchored protein biosynthesis. Conclusions In this work, the Lipidomics approach based on UPLC-Q-TOF/MS was employed to investigate serum metabolic changes in the rat model, 13 potential biomarkers related to hyperuricemia were identified, primarily involved in glycerolphospholipid metabolism and glycosylphosphatidylinositol-anchored protein biosynthesis. Abnormal glycerophospholipid metabolism pathway may be associated with lipid metabolism disorder caused by hyperuricemia, while the relationship between hyperuricemia and glycosylphosphatidylinositol-anchored protein biosynthesis needs further study.

Computed tomography (CT) has its irreplaceable function in nondestructive testing and medical diagnosis. In some practical CT imaging applications, the limited-angle scanning is common due to X-ray's potential harm to human and the limitation of the scanning conditions. Under these circumstances, analytic reconstruction algorithms, like filtered backprojection (FBP), will not obtain satisfactory results because of lacking the projection data. Iterative reconstruction (IR) methods that can incorporate prior knowledge have attracted attention in many fields, and wavelet frame-based regularization reconstruction algorithms have proven to be a useful means to reduce slope artifacts and noise for limited-angle CT. However, with the obtained projection data of the scanned object further reduces, the edge structures and the details of the reconstructed image worsen. For the sake of improving the quality of the reconstructed image from the limited-angle projection data, a guided image filtering (GIF)-based limited-angle CT reconstruction algorithm using wavelet frame was proposed. In each iteration of the proposed algorithm, the reconstructed result constrained by the wavelet frame was used as the guidance image to transfer the important features it contains to the reconstructed result of SART method by GIF. Furthermore, some simulated experiments and real data tests were conducted to evaluate the feasibility and validity of the proposed algorithm, and the qualitative and quantitative indexes indicated that the proposed algorithm was superior to other iterative reconstruction algorithms in artifacts reduction, noise suppression, and structure preservation.

MEMS gyroscopes play an important role in inertial navigation measurements, which mainly works in n = 2 mode. However, mode matching is the basis for high-precision detection, which can improve the sensitivity, resolution, and signal-to-noise ratio of the gyroscopes. An initial frequency split is inevitably generated during the manufacturing process. There are two methods to eliminate the frequency split and to achieve mode matching for the gyroscopes, which are electrostatic tuning and mechanical trimming, respectively. In this paper, we report a novel ring MEMS resonator and a novel method of mechanical frequency tuning. The most prominent characteristic of the resonator is that 16 raised mass blocks are increased in the circumferential positions of the ring uniformly. This structural design can achieve mass-stiffness decoupling, which means that punching holes on the mass blocks only affects the mass distribution but the stiffness is almost unchanged for the resonator. We verify the mass-stiffness decoupling by way of comparing the simulation with the conventional resonator. In addition, we put up an online tuning platform based on a femtosecond laser and reduce a resonator’s frequency split from 23.3 Hz to 0.4 Hz, which reveals that the frequency split is linearly related to the removed mass. These findings will have a referential significance for other transducers.

Diarrhea-predominant irritable bowel syndrome (IBS-D) is one common chronic functional disease of the digestive system with limited treatments. The microbiota–gut–brain axis (MGBA) has a central function in the pathogeny of IBS-D, which includes the participation of many various factors, such as brain-gut peptides (BGPs), immune inflammation, and intestinal flora. Inspired by the drug combination in traditional Chinese medicine (TCM), our previous study discovered that berberine (BBR) and baicalin (BA) could form natural self-assemblies as BA-BBR nanoparticles (BA-BBR NPs) and showed synergistic effects against IBS-D. Here, we investigated the synergistic effects of BA-BBR NPs on IBS-D model mice induced by chronic restraint stress plus Senna alexandrina Mill decoction with the influence on MGBA. BA-BBR NPs showed the best therapeutic effect on improving visceral hypersensitivity and diarrhea on IBS-D model mice, compared with BBR, BA, and BA/BBR mixture. Furthermore, BA-BBR NPs significantly (P

ObjectiveDrawing a growth curve of multidrug-resistant Pseudomonas aeruginosa (MDR-PA) provides a foundation for susceptibility testing. By observing in vitro antibacterial activity and ultrastructure cthanges on MDR-PA of the effective components in the drug-containing serum of rats after the administration of Fuzheng Jiedu Huayu decoction (FJHD), we evaluated the inhibition and direct destruction effect of bacteria by TCM alone or combined with antibiotics.MethodsThe absorbance values of MDR-PA were determined at different detection time points, and a growth curve was drawn. After gavage with FJHD, drug-containing serum was collected from the rats. Using Imipenem/cilastatin sodium as the positive drug control, the in vitro antibacterial potency of FJHD and its drug-containing serum alone or in combination with antibiotics against MDR-PA was observed. The ultrastructural changes of MDR-PA treated by FJHD combined with antibiotics were observed by transmission electron microscopy.ResultsGrowth of the experimental strain manifested a lag phase in the first 1–4 h, an exponential growth phase at 5–20 h, and a plateau phase after 20 h. The best detection time during the susceptibility test was 16–20 h. The minimum inhibitory concentration (MIC) value of the FJHD extract group was 0.2 g/mL. The MIC value of the pure Imipenem/cilastatin sodium group was 16 μg/mL. The MIC values of Imipenem/cilastatin sodium + blank serum, 0.5-, 1-, and 2-fold drug-containing serum groups were all 16 μg/mL. The MIC values of Imipenem/cilastatin sodium + 4- and 8-fold drug-containing serum groups were both 8 μg/mL. By observation under a transmission electron microscope, Imipenem/cilastatin sodium + 0.5-, 1-, and 2-fold drug-containing serum groups showed bacterial structural damage. The degree of bacterial destruction was more obvious and the quantity of damaged bacteria was increased in the Imipenem/cilastatin sodium + 4- and 8-fold drug-containing serum groups.ConclusionDrawing the growth curve of the experimental strain had high application value for ensuring the accuracy of the drug sensitivity test results. TCM combined with antibiotics could enhance the antibacterial and direct destruction effect of bacteria in vitro, thereby inhibiting bacterial resistance to a certain extent.

Limited-angle computed tomography (CT) reconstruction problem is an ill-posed inverse problem. Currently, regularized CT reconstructions are usually considered by incorporating the total variation (TV) norm of an image into data fidelity term. However, the reconstructed images may be degraded using the TV-based minimization method with limited-angle artifacts. In recent years, the theory of wavelet tight frame has been well developed and has some advantages in preserving the sharp features as well as smoothness. To further improve the quality of reconstructed images, we propose an image reconstruction method incorporating TV with wavelet tight frame for limited-angle CT problem, which objective function includes ℓ1 and ℓ0 regularization terms and solved by a TV-based simultaneous algebraic reconstruction technique and an alternating direction method of multipliers. Compared with some TV-based reconstruction methods, the experimental results show that our method can further improve the quality of reconstructed images and suppress the limited-angle artifacts as well as preserve the low-contrast objects.

Microrobots have a wide range of applications. The rigid–flexible composite stereoscopic technology based on ultraviolet laser cutting technology is primarily researched for the design and manufacture of microrobots and has been used to fabricate microscale motion mechanisms and robots. This paper introduces a monolithic processing technology based on the rigid–flexible composite stereoscopic process. Based on this process, a split-actuator micro flapping-wing air vehicle with a size of 15 mm × 2.5 mm × 30 mm was designed. We proposed a batch manufacturing method capable of processing multiple micro air vehicles at the same time. The main structure of 22 flapping-wing micro air vehicles can be processed at the same time within the processing range of the composite sheet with an area of 80 mm × 80 mm, and the processing effect is good.

A miniature deformable squama mechanics based on piezoelectric actuation inspired by the deformable squama is proposed in this paper. The overall size of the mechanics is 16 mm × 6 mm × 6 mm, the weight is only 140 mg, the deflection angle range of the mechanical deformation is −15°~45°, and the mechanical deformation is controllable. The small-batch array processing of the miniature deformable squama mechanics, based on the stereoscopic process, laid the technological foundation for applying the deformed squama array arrangement. We also designed and manufactured a small actuation control boost circuit and a mobile phone piezoelectric control assistant application that makes it convenient to perform short-range non-contact control of the deformation of the squama. The proposed system arranges the deformed squamae into groups to form the skin and controlls the size and direction of the signals input to each group of the squama array, thereby making the skin able to produce different shapes to create deformable skin.

MEMS capacitance diaphragm gauge with a full range of (1∼1000) Pa is considered for its wide application prospect. The design of pressure-sensing diaphragm is the key to achieve balanced performance for this kind of gauges. The optimization process of the pressure-sensing diaphragm with island design of a capacitance diaphragm gauge based on MEMS technique has been reported in this work. For micro-components in micro scale range, mechanical properties are very different from that in the macro scale range, so the size effect should not be ignored. The modified strain gradient elasticity theory considering size effect has been applied to determine the bending rigidity of the pressure-sensing diaphragm, which is then used in the numerical model to calculate the deflection-pressure relation of the diaphragm. According to the deflection curves, capacitance variation can be determined by integrating over the radius of the diaphragm. At last, the design of the diaphragm has been optimized based on three parameters: sensitivity, linearity and ground capacitance. With this design, a full range of (1∼1000) Pa can be achieved, meanwhile, balanced sensitivity, resolution and linearity can be kept.

Background/Aims: MicroRNAs (miRNAs) have a key role in carcinogenesis and cancer development, but the role of miRNAs in the progression of esophageal cancer (EC) remains unclear. Methods: The TE-1 and Eca-109 EC cell lines were used. The expression of miR-491 and candidate gene TPX2 in EC samples (n=99) were detected by RT-PCR. The cells invasive ability was determined by transwell assay. The luciferase reporter assay was used to confirm the regulation mechanism. Results: A decreased expression of miR-491 was detected in the EC clinical samples compared with the corresponding adjacent tumor tissues. Aberrant expression of miR-491 regulated cells invasion and EMT markers. Furthermore, we verified that TPX2 was a target gene of miR-491. Conclusions: miR-491 may play a critical role in EC.

Conductometric semiconducting metal oxide gas sensors have been widely used and investigated in the detection of gases. Investigations have indicated that the gas sensing process is strongly related to surface reactions, so one of the important parameters of gas sensors, the sensitivity of the metal oxide based materials, will change with the factors influencing the surface reactions, such as chemical components, surface-modification and microstructures of sensing layers, temperature and humidity. In this brief review, attention will be focused on changes of sensitivity of conductometric semiconducting metal oxide gas sensors due to the five factors mentioned above.

Too much reliance has been placed on calculating single images meeting possibly arbitrary optimization criteria. By generating a dispersion of multiple images consistent with the data, we may be able to learn how wrong we could be. Our problem is to generate a way of seeing a representative sample of all of the solutions in the hyperplane of solutions, which would be an array of images, each of which is a solution to the equations. To accomplish this, we suggest that our sampling is in a space of image basis functions, rather than directly in the hyperplane. As the number of basis functions is large, we design a selection criterion for choosing a subset that reasonably spans the space of images. First, we try a random sampling, which gives high frequency or sequency samples. Then we turn to more systematic sampling, based on the methods developed for one-pixel imaging. Some numerical experiments demonstrate that the use of basis functions as starting images for ART-like iterative algorithms may suffice to span the hyperplane of solutions, allowing choices between solutions other than simple optimization of arbitrary criteria such as minimum norm or maximum entropy, or deconvolution of the point spread function of the algorithm. [ABSTRACT FROM AUTHOR]

The sensor network is an important part of the real-time monitoring system of traffic flow in tourist areas. In this study, we built a traffic flow prediction model based on machine learning to assist the construction and optimization of a sensor network. Using the sensor network, we developed a real-time monitoring system of traffic flow in tourist areas. Factors affecting traffic flow in the study area (Hongze Lake, China) were determined through interviews with 50 tourists. Using the scores of the factors, machine learning models such as random forest, decision tree, and support vector machine were constructed to predict traffic flow, and the result was used to design an appropriate sensor network. The predictions of three machine learning methods were compared to build a traffic flow prediction model. After comparing the predicted results with the tested ones, the performance of the prediction model was validated. Referring to such results, we selected the area near a square and bridges and the intersections of roads as key areas to install sensors for monitoring traffic flow. The system is being implemented in the study area to renovate the area to promote further growth of the tourism industry. [ABSTRACT FROM AUTHOR]

Lithium-oxygen batteries (LOBs) have extensive applications because of their ultra-high energy densities. However, the practical application of LOBs is limited by several factors, such as a high overpotential, poor cycle stability, and limited rate capacity. In this paper, we describe the successful uniform loading of Mn3O4 nanoparticles onto multi-walled carbon nanotubes (Mn3O4@CNT). CNTs form a conductive network and expose numerous catalytically active sites, and the one-dimensional porous structure provides a convenient channel for the transmission of Li+ and O2 in LOBs. The electronic conductivity and electrocatalytic activity of Mn3O4@CNT are significantly better than those of MnO@CNT because of the inherent driving force facilitating charge transfer between different valence metal ions. Therefore, the Mn3O4@CNT cathode obtains a low overpotential (0.76 V at a limited capacity of 1000 mAh g-1), high initial discharge capacity (16895 mAh g-1 at 200 mA g-1), and long cycle life (97 cycles at 200 mA g-1). This study provides evidence that transition metal oxides with mixed-valence states are suitable for application as efficient cathodes for LOBs. [ABSTRACT FROM AUTHOR]

Developing highly conductive, stable, and active hydrogen evolution reaction (HER) catalysts is a critical step towards establishing the hydrogen economy. However, there are few catalysts, except for noble metals, that can meet all the requirements. Recently, two-dimensional (2D) transition metal carbon/nitride (MXene) materials have shown excellent performance in catalysis, and have attracted wide attention from researchers. In this study, the effectiveness of non-metal element (B, C, N, P, and S)-doped Ti3 C2 O2 MXene in the electrocatalytic hydrogen evolution reaction was investigated using density functional theory (DFT) calculations. Non-metal atoms as electron donors can provide additional electrons to the O functional group on the catalyst surface, thereby reducing charge transfer from H to O and the interaction between H and O. The Gibbs free energy (ΔG H) of non-metal element-doped Ti3 C2 O2 is closer to 0 than that of pristine Ti3 C2 O2, demonstrating better hydrogen evolution performance. Furthermore, in the hydrogen evolution path, the desorption process is more inclined to the Heyrovsky mechanism, and doping greatly reduces the energy barrier of the reaction, thereby improving the catalytic efficiency. The present results prove that doping with non-metallic elements is an effective means of improving the catalytic activity of Ti3 C2 O2 for hydrogen evolution. [ABSTRACT FROM AUTHOR]