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In this study, a pH-responsive polycaprolactone (PCL)–copper peroxide (CuO2) composite antibacterial coating was developed by suspension flame spraying. The successful synthesis of CuO2 nanoparticles and fabrication of the PCL-CuO2 composite coatings were confirmed by microstructural and chemical analysis. The composite coatings were structurally homogeneous, with the chemical properties of PCL well maintained. The acidic environment was found to effectively accelerate the dissociation of CuO2, allowing the simultaneous release of Cu2+ and H2O2. Antimicrobial tests clearly revealed the enhanced antibacterial properties of the PCL-CuO2 composite coating against both Escherichia coli and Staphylococcus aureus under acidic conditions, with a bactericidal effect of over 99.99%. This study presents a promising approach for constructing pH-responsive antimicrobial coatings for biomedical applications. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) is known to be an efficient elicitor of secondary metabolism in plants. Arbutin, a characteristic phenolic glycoside found in 'Yuluxiang' pear (Pyrus bretschneideri Rehder × Pyrus sinkiangensis Yu), is widely used in lightening agents, in addition to cough, anti-inflammatory, and anti-microbial remedies, among other applications. However, research into the synthesis of arbutin in pear is limited. This study aimed to clarify the effect of exogenous SA on the arbutin content of pear using HPLC and investigate the mechanism for arbutin accumulation using RNA-Seq analysis. HPLC revealed that SA increased the arbutin contents of leaf, fruit, and callus in pear and demonstrated that the effect of SA is concentration and time dependent. RNA-Seq analysis of pear callus treated with or without SA revealed 380 differentially expressed genes (DEGs), 335 of which were up-regulated. According to a KEGG database analysis, the highest number of genes were annotated for phenylpropane biosynthesis. Overall, 21 DEGs were found to be involved in the synthesis of hydroquinone and UDP-glucose, which are substrates of arbutin synthesis. It is noteworthy that the expression levels of three up-regulated genes (Pbr006844.1, Pbr021064.1 and Pbr021069.1) related to hydroquinone glycosyltransferase were induced by SA and hydroquinone. Furthermore, transient overexpression of PbUGT72B1 (Pbr021069.1) increased the arbutin content in pear callus. These data explain the regulation of gene transcription associated with the promotive effect of SA on arbutin biosynthesis in pear, thus providing a theoretical foundation for enhancing the arbutin content of fruit through genetic engineering. [ABSTRACT FROM AUTHOR]

There were some ecological and environmental problems in limestone soil in the karst peak-cluster depression in Pingguo City of Guangxi, such as the destruction of soil structure, soil acidification and soil fertility decline, and these problems were closely related to soil organic matter. The soil in this site was classified as Cambisols. Therefore, this project took soil under five major land uses (grassland, afforestation, sugarcane field, corn field and pitaya field) in the karst area of Guangxi as the research object. The contents and molecular structure properties of humic acids, fulvic acids and humins in soils were studied by solid-state 13C nuclear magnetic resonance spectroscopy and elemental composition. From the perspective of the chemical structure of humic substances, the differences in the quantity and structural characteristics of humic acids, fulvic acids and humins in different land uses were revealed. The results showed that the organic carbon content of both afforestation (34.83 g kg−1) and natural restored grassland (31.67 g kg−1) were significantly higher than that of sugarcane field (17.60 g kg−1), corn field (16.35 g kg−1) and pitaya field (14.31 g kg−1) (p < 0.05). The contents of three humic fractions in grassland were relatively high, and the contents of three humic fractions in sugarcane field were relatively low (p < 0.05). The structural characteristics of humic substances showed that the protein components of the three humic fractions in the afforestation were high, indicating that the humic substances in the afforestation contained more unstable components. The Alkyl C/O-alkyl C and Hydrophobic C/hydrophilic C ratios of the three humic fractions of corn field were high, indicating high stability and maturity in humic substances in corn field. [ABSTRACT FROM AUTHOR]

As vane inlet temperatures and turbine loadings are increasing, the aerodynamic and thermal management for the endwalls of gas turbines have received increased attention. Non-axisymmetric endwalls are becoming popular due to their proficient capabilities to modify the secondary flow fields and to change the film cooling performance on the endwalls. In this study, by considering the interaction between mainstream and purge flow based on non-axisymmetric endwall contouring, the numerical research model used in the present research was established. Based on the validated numerical method, the influence of the non-axisymmetric endwall contouring on the film-cooling effectiveness and aerodynamic characteristics was studied. Furthermore, the effect of different inclination angles on the film-cooling performance of the contoured endwalls was also investigated. The results indicate that for the high-load turbine vane used in this research, various types of non-axisymmetric endwall contouring can alter the aero-dynamic characteristics and cooling performance simultaneously. By inhibiting the secondary flows, non-axisymmetric endwall contouring can reduce the total cascade pressure loss coefficient by 0.305%. In addition, non-axisymmetric endwall contouring can significantly enhance the effective coverage area of purge flow up to 28.29%, and the endwall near the suction side can achieve better cooling performance. Finally, non-axisymmetric endwall contouring can improve the protective effect of large-angle purge flow. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have been extensively explored to show good optical features, low toxicity, and good biocompatibility. Herein, we report the new synthesis of forsythia-derived CDs (F-CDs) and their incorporation into Nylon-11 nanofibers for improved mechanical properties and biocompatibility. F-CDs are prepared from a Chinese herb forsythia via a magnetic hyperthermia method in 90 s without the use of any organic solvents. The as-prepared F-CDs with rich surface functional groups can be well embedded into Nylon-11 nanofibers via electrospinning, providing Nylon-11/F-CD nanofiber mats with remarkably enhanced mechanical properties. With the incorporation of F-CDs at 10 wt% into the Nylon-11 nanofiber mats, the tensile strength increases from 7.5 to 16.6 MPa, and the elongation ratio at break increases from 39% to 125%. Moreover, the Nylon-11/F-CD nanofiber mats exhibit excellent cytocompatibility towards L929 fibroblast cells with cell viability of 96%. These findings may guide the development of various CD-embedded nanofiber mats with good mechanical properties and biocompatibility potentially useful for biomedical applications, such as tissue engineering scaffolds or wound dressing. [ABSTRACT FROM AUTHOR]

Exploring the health risks of diseases attributed to PM2.5 and SO2 exposure and analyzing the differences in their distribution over emissions can provide useful insights for decision-makers to reduce premature mortality due to PM2.5 and SO2 exposure. This study used exposure-response functions, health risk inequality curve (HRICU, based on Lorenz curve), and the health risk inequality coefficient (HRICO, based on Gini coefficient) to estimate population health risks of PM2.5 and SO2 exposure in China from 2013 to 2017 based on a full-coverage, high-precision PM2.5 and SO2 concentration and emission dataset. The inequality in the distribution of premature mortality was explored in terms of pollutant emissions. The results showed that (1) premature mortalities from cardiovascular disease (CVD) and respiratory disease (RD) due to PM2.5 and SO2 exposure decreased by 21% and 54%, respectively, from 2013 to 2017. (2) At a national scale, the HRICO value for the distribution of PM2.5 and SO2 health risks on emissions were lower than 0.10 and 0.20, respectively. (3) More than 20% of provinces had HRICO values above 0.1 for PM2.5 or SO2. The provinces near the national borders generally had higher HRICO for PM2.5, while the province with the most severe inequity in the distribution of SO2 health risks on emissions appeared in Xinjiang Uygur Autonomous Region, Ningxia Hui Autonomous Region, and Hainan Province. [ABSTRACT FROM AUTHOR]

Chito-oligosaccharides (COSs) were encapsulated by the film-ultrasonic method into three nano-liposomes, which were uncoated liposomes (COSs-Lip), chitosan-coated liposomes (CH-COSs-Lip), and sodium alginate (SA)/chitosan (CH)-coated liposomes (SA/CH-COSs-Lip). The physicochemical and structural properties, as well as the stability and digestive characteristics, of all three nano-liposomes were assessed in the current study. Thereafter, the characteristics of intestinal absorption and transport of nano-liposomes were investigated by the Caco-2 cell monolayer. All nano-liposomes showed a smaller-sized distribution with a higher encapsulation efficiency. The ζ-potential, Z-average diameter (Dz), and polydispersity index (PDI) demonstrated that the stability of the SA/CH-COSs-Lip had much better stability than COSs-Lip and CH-COSs-Lip. In addition, the transport of the nano-liposomes via the Caco-2 cell monolayer indicated a higher transmembrane transport capacity. In summary, the chitosan and sodium alginate could serve as potential delivery systems for COSs to fortify functional foods and medicines. [ABSTRACT FROM AUTHOR]

Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to (1) assess parental hesitancy about category A (Expanded Program on Immunization (EPI)) and B (non-EPI) vaccines, (2) assess parental willingness for COVID-19 and influenza vaccinations, and (3) explore the association of vaccination hesitancy of parents and healthcare workers (HCWs). Methods: The study was performed in Wuxi, eastern China between 21 September 2020 and 17 October 2020. Parents of children aged <18 years and HCWs were recruited from the selected immunization clinics. Vaccine hesitancy was assessed using the Strategic Advisory Group of Experts (SAGE) vaccine hesitancy survey (VHS) by summing the total score for 10 items (maximum 50 points). Results: A total of 3009 parents and 86 HCWs were included in the analysis. The category A VHS scores were significantly higher than the category B VHS scores (p = 0.000). Overall, 59.3% and 52.4% of parents reported willingness to avail COVID-19 and influenza vaccination for their children, respectively; 51.2% of the HCWs wanted to be vaccinated against COVID-19. Parental category B VHS scores were associated with HCW category B VHS scores (r = 0.928, p = 0.008). Conclusions: In China, parents are more hesitant about category B vaccines than category A vaccines. More than 40% of parents showed hesitancy and a refusal to use COVID-19 and influenza vaccines. [ABSTRACT FROM AUTHOR]

The publish/subscribe model has gained prominence in the Internet of things (IoT) network, and both Message Queue Telemetry Transport (MQTT) and Constrained Application Protocol (CoAP) support it. However, existing coverage-based fuzzers may miss some paths when fuzzing such publish/subscribe protocols, because they implicitly assume that there are only two parties in a protocol, which is not true now since there are three parties, i.e., the publisher, the subscriber and the broker. In this paper, we propose MultiFuzz, a new coverage-based multiparty-protocol fuzzer. First, it embeds multiple-connection information in a single input. Second, it uses a message mutation algorithm to stimulate protocol state transitions, without the need of protocol specifications. Third, it uses a new desockmulti module to feed the network messages into the program under test. desockmulti is similar to desock (Preeny), a tool widely used by the community, but it is specially designed for fuzzing and is 10x faster. We implement MultiFuzz based on AFL, and use it to fuzz two popular projects Eclipse Mosquitto and libCoAP. We reported discovered problems to the projects. In addition, we compare MultiFuzz with AFL and two state-of-the-art fuzzers, MOPT and AFLNET, and find it discovering more paths and crashes. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) have been reported to use aminopeptidase N (APN) as a cellular receptor. Recently, the role of APN as a receptor for PEDV has been questioned. In our study, the role of APN in PEDV and TGEV infections was studied in primary porcine enterocytes. After seven days of cultivation, 89% of enterocytes presented microvilli and showed a two- to five-fold higher susceptibility to PEDV and TGEV. A significant increase of PEDV and TGEV infection was correlated with a higher expression of APN, which was indicative that APN plays an important role in porcine coronavirus infections. However, PEDV and TGEV infected both APN positive and negative enterocytes. PEDV and TGEV Miller showed a higher infectivity in APN positive cells than in APN negative cells. In contrast, TGEV Purdue replicated better in APN negative cells. These results show that an additional receptor exists, different from APN for porcine coronaviruses. Subsequently, treatment of enterocytes with neuraminidase (NA) had no effect on infection efficiency of TGEV, implying that terminal cellular sialic acids (SAs) are no receptor determinants for TGEV. Treatment of TGEV with NA significantly enhanced the infection which shows that TGEV is masked by SAs. [ABSTRACT FROM AUTHOR]

Low impact development (LID) is a storm management philosophy. This paper aims at choosing the LID for urban storm management by comparing the efficiency in the south urban district in the Taiyuan Basin. Firstly, we set up a 1D–2D model to simulate the hydrological and hydraulic process of the area. Then the efficiency of different LID scenarios was analyzed by ratio of surcharging pipeline, percentage of ponding road, external outflow, infiltration, surface runoff, facility storage, and LID area ratio. It was found that the continuous porous pavement and rain garden are beneficial for use in residential and commercial settings in urban areas, and the rain garden performs more effectively and efficiently than the continuous porous pavement. The area occupied by LID might be under 20% of the impervious building area, because the LID performance was not improved significantly with the LID area when the ratio exceeded 20%. The LIDs could be more useful for small return periods and short duration storms, and could not replace conventional runoff management practices and drainage systems. [ABSTRACT FROM AUTHOR]

The impact of various amounts of konjac glucomannan on the structural and physicochemical properties of gluten proteins/dough at different periods of frozen storage is evaluated in the present study. As frozen storage time was prolonged, the molecular weight and the free sulfhydryl content of gluten proteins and the tensile properties of frozen dough all decreased. The addition of konjac glucomannan reduced the variations in the structural and rheological properties of gluten proteins/dough. Frozen dough with 2.5% added konjac glucomannan showed the highest water binding capacity and retarded the migration of water. Scanning electron microscopy and differential scanning calorimetry results also revealed that adding konjac glucomannan reduced the cracks and holes in the dough and enhanced its thermal stability. The correlations between mechanical characteristics and structure parameters further indicated that konjac glucomannan could not only stabilize the structures of gluten proteins but also bind free water to form more stable complexes, thereby retaining the rheological and tensile properties of the frozen dough. [ABSTRACT FROM AUTHOR]

In the absence of long-series streamflow records in plain areas, design storm, which serves as the most important input in a hydrologic model, plays an important role in flood control and water resources management. For a large drainage basin, design storm may be estimated for sub-basins separately; thus the spatial distribution of design storm needs to be carefully treated. However, few studies have been carried out to evaluate the rationality of the spatial distribution in a design storm, which means the storm over space should be in accordance with actual needs or its distributing patterns. Taking the Tai Lake Basin (TLB), 3-d Copula-based models combining extreme rainfall of different sub-basins were built using long-term rainfall data, and conditional probabilities of sub-basins encountering certain amounts of rainfall were investigated to evaluate the rationality of the design storm. Results show that the spatial distribution of the design storm based on a typical year is hardly rational, in which rainfall of the northeastern part of the basin is suggested to be weakened while in the southwest to be strengthened; after the rainfall is redistributed based on long-term information, it shows a better rationality of spatial distribution. Such information provides valuable significance in guiding flood control of TLB, and the considered evaluating method can be used for similar basins in plain areas. [ABSTRACT FROM AUTHOR]

For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable., Competing Interests: The authors declare no conflict of interest.

Low-cost GPS (receiver) has become a ubiquitous and integral part of our daily life. Despite noticeable advantages such as being cheap, small, light, and easy to use, its limited positioning accuracy devalues and hampers its wide applications for reliable mapping and analysis. Two conventional techniques to remove outliers in a GPS trajectory are thresholding and Kalman-based methods, which are difficult in selecting appropriate thresholds and modeling the trajectories. Moreover, they are insensitive to medium and small outliers, especially for low-sample-rate trajectories. This paper proposes a model-based GPS trajectory cleaner. Rather than examining speed and acceleration or assuming a pre-determined trajectory model, we first use cubic smooth spline to adaptively model the trend of the trajectory. The residuals, i.e., the differences between the trend and GPS measurements, are then further modeled by time series method. Outliers are detected by scoring the residuals at every GPS trajectory point. Comparing to the conventional procedures, the trend-residual dual modeling approach has the following features: (a) it is able to model trajectories and detect outliers adaptively; (b) only one critical value for outlier scores needs to be set; (c) it is able to robustly detect unapparent outliers; and (d) it is effective in cleaning outliers for GPS trajectories with low sample rates. Tests are carried out on three real-world GPS trajectories datasets. The evaluation demonstrates an average of 9.27 times better performance in outlier detection for GPS trajectories than thresholding and Kalman-based techniques., Competing Interests: The authors declare no conflict of interest.