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This research utilizes both single crystal and polycrystalline models to probe the fatigue crack propagation mechanism in pure silver via molecular dynamics (MD) simulations. A comprehensive validation approach at both micro and macro scales, incorporating transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and compact tension (CT) specimen fatigue testing, is developed to verify the reliability of simulation models and results. Simulation findings indicate that the initial crack orientation significantly influences crack propagation. As the crack advances within the crystal, two primary crack propagation mechanisms are discerned: (1) nano-voids appear at the crack tip, and the crack propagates by continuously aggregating with the nano-voids ahead; (2) the formation of Stair-rod dislocations and V-shape stacking faults due to dislocation reactions and slip band movements impedes crack propagation, accompanied by the dislocation reaction of Shockley partial dislocations ( 1 6 <112>) generating Hirth dislocations ( 1 6 <110>). The dislocation reaction is verified through the dislocation analysis of the crack tip area of the CT specimen after fatigue experiment by using TEM. In addition, the results of this study show that the angle between the direction of crack propagation and the grain boundary affects the fatigue crack propagation, e.g. when the angle is less than 60°, the crack rapidly propagates along the grain boundary. The orientation distribution function (ODF) results of EBSD can verify that the polycrystalline model containing 30 grains is a reliable model for the MD simulation of behavior of the crack tip of CT specimen. Lastly, the Paris law constants for pure silver are determined as m = 3.72 and lg C = − 10.77, providing a reference for the fatigue analysis and life prediction of silver components or silver soldering pots in engineering applications. [ABSTRACT FROM AUTHOR]

Numerous publications have discussed the nexus between managerial ability (MA) and innovation capability; however, regarding the hi-tech enterprises in transition economies, the nexus between MA and R&D efficiency will be discussed in depth. Considering the data from high-tech listed companies A-shares in Mainland China in 2012–2017, the data envelopment analysis (DEA) window, Tobit panel model, and panel threshold model is utilised to analyse the direct, moderating effects and threshold effect of MA on R&D efficiency of China’s high-tech enterprises. The findings illustrated that MA could significantly facilitate R&D efficiency, and this enhancement effect is interestingly more evident in state-owned enterprises. Enterprise ownership exerts a significant positive moderation effect between MA and R&D efficiency of China’s hi-tech enterprises. Both equity incentive and salary incentive exerts a significant negative moderation effect between MA and R&D efficiency of China’s hi-tech enterprises. In addition, the panel threshold model proved a nonlinear nexus between MA and its R&D efficiency. Based on the abovementioned findings, corresponding countermeasures are proposed. [ABSTRACT FROM AUTHOR]

Track geometry monitoring is essential for track maintenance. Dedicated track inspection vehicles are scheduled to measure track geometry irregularities throughout the railway network, so cannot inspect each line frequently. It is desirable to inspect geometry much higher frequently using in-service trains. One possible way is estimating track geometry from vehicle–body accelerations because the accelerators can be easily installed in vehicle–body. However, inverting track geometry from vehicle–body acceleration is a pending issue. Up to now, most research has focused on vehicle dynamics modelling and simulation. In this paper, we solve the problem using deep learning method and realistic measurement data. The training and test data are the inspection data acquired by comprehensive inspection trains from three main high-speed railways in China. The proposed AM–CNN–GRU model combines an Attention Mechanism (AM), a Convolutional Neural Network (CNN) and a Gated Recurrent Unit (GRU). The model's inputs are vertical and lateral accelerations, and vehicle speed. The outputs are two vertical track irregularities, with wavelengths of 3–42m and 3–120 m, respectively. We evaluated the model by comparing the estimated irregularities with the actual measurements. We discussed different models, high-speed lines, sub-rail infrastructures and speed to validate the model effectiveness. [ABSTRACT FROM AUTHOR]

To improve the quality of track maintenance work, it is a desire to estimate vehicle dynamic behavior from track geometry irregularities. This paper proposes a deep learning model to predict vehicle responses (e.g., vertical wheel-rail forces, wheel unloading rate, and car body vertical acceleration) using deep learning techniques. In the proposed CA-CNN-MUSE model, convolutional neural networks (CNNs) are used to learn features of track irregularities, and multiscale self-attention mechanisms (MUSE) are employed to capture the long-term and short-term trends of sequences. Coordinate attention (CA) is introduced into CNN to focus on important interchannel relationships and important spatial mileage points. The experiments were performed on a multibody simulation model of the vehicle system and the measured data of the actual high-speed line. The results show that the CA-CNN-MUSE has high prediction accuracy for vertical vehicle responses and fast computation speed. The predicted time-domain waveforms and power spectral densities (PSDs) agree well with the actual vehicle responses. The main features of the lateral vehicle responses can also be captured by the proposed method, yet the results are not as good as the vertical ones. [ABSTRACT FROM AUTHOR]

• Kalina cycle based power/refrigeration cogeneration cycle (PPRAT-KC) was studied. • Adjustable range of refrigeration temperature is about from -22℃ to 7.5℃. • Adjustment of refrigeration temperature has no effect on amounts of energy outputs. • Amount of net power or refrigeration energy output can be flexibly adjusted. • The PPRAT-KC can maintain high performance when altering refrigeration temperature. Two schemes of power and refrigeration cogeneration Kalina cycle with adjustable refrigeration temperature (PPRAT-KC) based on the efficient cogeneration cycle PPR-KC are proposed and studied. In the PPRAT-KC, the refrigerant vapor is absorbed in a pressure adjustment absorber with dilute solution either from the separator or the low-pressure pump, and by altering the flow rate of the dilute solution, the refrigeration temperature is able to be adjusted with nearly no effect on the amounts of energy outputs. The amount of net power or refrigeration capacity in the PPRAT-KC can be also adjusted by changing the flow rate of solutions fed to the power and refrigeration sub-cycles. Under temperatures of heat source and cooling water of 400℃ and 30℃, respectively, the change range of refrigeration temperature for the two schemes of the PPRAT-KC are about from -22℃ to 7.5℃, and the performances of the two schemes are similar. With the same work concentration of 0.5 and refrigeration temperature of -15℃, the effective exergy effeciency of PPRAT-KC is 0.5653, which is 4.145% and 10.97% higher than those of the PPR-KC and the triple pressure Kalina cycle, respectively. [ABSTRACT FROM AUTHOR]

Urban flooding can be predicted by using different modeling approaches. This study considered different methods of modeling the dynamic flow interactions between pipe systems and surface flooding in urban areas. These approaches can be divided into two categories based on surface runoff collection units. This paper introduces a new hydrodynamic model that couples the storm water management model and the 2D overland model. The model's efficiency was validated based on the aforementioned experimental dataset; agreement was verified by correlation values above 0.6. Additionally, this study used different approaches and compared their accuracy in predicting flooding patterns. The results show that the use of sub-catchments to model the collection of surface runoff was not predictive of the inundation process, indicating a lower goodness of fit with the recorded values than that of adopting cells. Moreover, to determine which method of adopting cells to collect runoff could better predict rainstorm-induced inundation, an error and correlation analysis was conducted. The analysis found low error and high correlation, suggesting that inundation can be effectively predicted by the new approaches. Ultimately, this study contributes to existing work on numerical analysis of the interaction methods of urban flooding. [ABSTRACT FROM AUTHOR]

Genotype S H9N2 avian influenza virus, which has been predominant in China since 2010, contributed its entire internal gene cassette to the genesis of novel reassortant influenza viruses, including H5Nx, H7N9 and H10N8 viruses that pose great threat to poultry and humans. A key feature of the genotype S H9N2 virus is the substitution of G1‐like M and PB2 genes for the earlier F/98‐like M and PB2 of genotype H virus. However, how this gene substitution has influenced viral adaptability of emerging influenza viruses in mammals remains unclear. We report here that reassortant H5Nx and H7N9 viruses with the genotype S internal gene cassette displayed enhanced replication and virulence over those with genotype H internal gene cassette in cell cultures as well as in the mouse models. We showed that the G1‐like PB2 gene was associated with increased polymerase activity and improved nuclear accumulation compared with the F/98‐like counterpart, while the G1‐like M gene facilitated effective translocation of RNP to cytoplasm. Our findings suggest that the genotype S H9N2 internal gene cassette, which possesses G1‐like M and PB2 genes, is superior to that of genotype H, in optimizing viral fitness, and thus have implications for assessing the potential risk of these gene introductions to generate emerging influenza viruses. [ABSTRACT FROM AUTHOR]

• Combined cycle capable of offering three switchable energy supply modes was studied. • The set of the evaporator ensures the effective switching of different cycle modes. • Heat source in low temperature grade helps to desorb the work or basic solution. • Analysis was conducted from both thermodynamic and economic perspectives. • All cycle modes can maintain high comprehensive performance. The emergence of energy-related issues and the growing need for year-round energy supply has created a pressing demand for efficient cogeneration combined cycles. To this end, a new combined cycle using ammonia-water as the working fluid is proposed and studied from both thermodynamic and economic standpoints in this paper. The proposed cycle can effectively operate in power generation, power/refrigeration cogeneration and power/heating cogeneration modes. Parametric analysis and performance optimization of the proposed cycle are carried out, and the genetic algorithm method is employed for the optimization. Under the same initial conditions, the proposed cycle exhibits comprehensive power recovery efficiencies that are 58.11 %, 23.85 %, and 7 % relatively higher than those of the compared cogeneration cycles and Kalina cycle reported in the literature, respectively. The optimization results show that the maximum comprehensive power recovery efficiencies for the power/refrigeration, power/heating and power modes with heat source/cooling water temperature of 250℃/30℃, are 0.2271, 0.2658, and 0.1789, respectively. The associated power/refrigeration, power/heating, and power outputs are 221.1 kW/417.8 kW, 248.5 kW/650.9 kW, and 292.1 kW, respectively. Under these conditions, the overall annual unit cost of comprehensive power and the payback period of the cycle are 0.03947 $/kWh and 3.898 years. Results of the comprehensive analysis indicate that the proposed cycle can achieve satisfactory comprehensive performance for each mode, while also sufficiently recovering sensible heat source. [ABSTRACT FROM AUTHOR]

Genotype S H9N2 viruses frequently donate their internal genes to facilitate the generation of novel influenza viruses, e.g., H5N6, H7N9, and H10N8, which have caused human infection. Genotype S was originated from the replacement of F/98-like M and PB2 genes of the genotype H with those from G1-like lineage. However, whether this gene substitution will influence the viral fitness of emerging influenza viruses remains unclear. We found that H5Nx and H7N9 viruses with G1-like PB2 or M gene exhibited higher virulence and replication than those with F/98-like PB2 or M in chickens. We also determined the functional significance of G1-like PB2 in conferring increased polymerase activity and improved nucleus transportation efficiency, and facilitated RNP nuclear export by G1-like M. Our results suggest that G1-like PB2 and M genes optimize viral fitness, and thus play a crucial role in the genesis of emerging influenza viruses that cause rising prevalence in chickens. • Genotype S H9N2 AIV donate their internal gene cassette to facilitate the generation of H5N6, H7N9, etc. • Genotype S H9N2 is the substitution of G1-like PB2 and M genes for the earlier F/98-like M and PB2 of genotype H. • G1-like H9N2 PB2 and M genes enhance virulence of reassortant H5Nx and H7N9 viruses in chickens. • Genotype S H9N2 internal gene cassette is superior to that of genotype H in optimizing viral fitness in chickens. [ABSTRACT FROM AUTHOR]

Abstract Three π-conjugated large organic molecules based on diketopyrrolopyrrole (DPP), benzodipyrrolidone (BDP) and naphthodipyrrolidone (NDP) are synthesized and characterized. By introducing bi-thiophene units at the end of DPP/BDP/NDP chromophores, the molecules are able to form a donor–acceptor–donor (D-A-D) system. All of them exhibit high thermal stability, strong aggregation, high values in highest occupied and low values in lowest unoccupied molecular orbital (HOMO/LUMO) energy levels. In this work, a simple solution process technique for large organic molecules crystal organic field-effect transistors (OFETs) is used to fabricate devices. DPP- and BDP-based large organic molecular crystals exhibit p-type behavior with hole mobility of 0.02 cm2 V−1 s−1 and 0.09 cm2 V−1 s−1, while large organic molecular crystal based on NDP shows n-type behavior with electron mobility up to 0.26 cm2 V−1 s−1. This work demonstrated that extension of the π-conjugation system is a useful strategy to build high charge mobility materials. In addition, BDP is an interesting electron-withdrawing block for p-type semiconductor while NDP is a promising chromophore for the construction of n-type high-performance OFETs. Graphical abstract Image 1 Highlights • Donor-acceptor type molecules based on DPP, BDP and NDP were synthesized and characterized. • Organic crystal field-effect transistors based on oligomer were studied. • NDP is a promising chromophore for construction n-type high-performance organic field-effect transistors. • Extension π-conjugation system is a useful strategy to build high charge mobility materials. [ABSTRACT FROM AUTHOR]

Highlights • One room with vertical greening system (VGS) and one without VGS were experimentally set up. • Thermal behavior of VGS in Wet and Cold Climates during Winter was investigated. • Two kinds of experiments, without heating and with heating, were conducted. • Significant energy saving was achieved by vertical greening system. Abstract In recent years, a novel vertical greening system has begun to spread worldwide. This system can provide several environmental benefits, such as alleviating urban heat island effects, increasing the number of green sceneries, improving atmospheric quality, relieving urban drainage pressures, and improving building energy efficiency. To evaluate the effect of a vertical greening system on indoor climate and the energy consumption of buildings under wet and cold climatic conditions during winter, contrastive experiments were performed in this study. Two experimental rooms of equal size with the same wall structures were set up in Hunan Province, China. One room had a vertical greening system, whereas the other room did not have one and was used as the reference room. Two types of experimental conditions, that is, with and without heating, were investigated. The experimental data were collected from December 2017, to January 2018. Results showed that without heating, the indoor air temperature swing of the room with vertical greening was significantly suppressed, in comparison with that of the reference room. The indoor air temperature of the room with vertical greening was 1–3°C higher than that of the reference room at night. Meanwhile, the air layer temperature was 1–2°C higher than that of the outdoor air throughout the day. Under heating conditions, the average heat flux through the walls of the reference room was 3.1 W/m2 larger than that of the room with vertical greening. The measured electric energy consumption of the reference room was 1.22 times that of the vertical green room. An energy saving rate of 18% was achieved during the heating experiment owing to the extra thermal insulation provided by the vertical greening system. [ABSTRACT FROM AUTHOR]

The global economy has accelerated the transition to a green, low-carbon economy. An enterprise's green innovation (GI) is directly related to its capacity for sustainable production as a micro-subject of economic development. This study examined the impact of managerial capacity on enterprise green innovation and changes of green innovation targeting. We used data collected manually from 423 Chinese A-share companies from 2010 to 2017. The effect of various external impact signals was then investigated. This study's findings are as follows: (1) Managerial ability stimulated green enterprise innovation. The marginal effect was 0.0696. While quality targeting has focused more on green invention innovation, managerial capacity significantly improved the marginal impact of green substantial innovation by 0.0375; (2) The clean production link targeting analysis confirmed that enterprises focused on end-of-pipe governance innovation (0.0466), along with new energy innovation (0.0495) rather than energy-saving innovation (−0.0227); (3) The multi-period DDD (Difference in Difference in Difference) model revealed that low-carbon city policy promoted green innovation with a diminishing trend; (4) The voluntary environmental regulation signals, ISO14001 certification, displayed a substitute effect for managerial capacity on enterprise green innovation. This paper provides recommendations, including that enterprises should improve the utilization of new and renewable energy while improving and optimizing production processes. The government should also improve innovation incentive policies and strengthen environmental information disclosure. • The marginal effect of managerial ability on enterprise green innovation is 0.0696. • Quality targeting focuses more on green invention innovation. • Link targeting focuses more on end-of-pipe governance innovation. • Low-carbon city policy promoted green innovation with a diminishing trend. • ISO14001 certification displayed a substitute effect in the process. [ABSTRACT FROM AUTHOR]

Firms introduce new products as a critical competitive strategy. This strategy not only changes the competitive structure of the market, but also provides consumers with a broader range of choices. In this study, we collected sales data for new energy vehicles in six Chinese cities from 2020 to 2021 and used a random coefficient logit model to analyze the competitive and welfare effects of the introduction of Tesla on the Chinese new energy vehicle market. Our empirical findings suggest that consumers prefer electric vehicles that are affordable, have low energy consumption per 100 km, have a moderate range, and are large and heavy. The own- and cross-price elasticities of the vehicle brands show that although Tesla faces fierce competition from Chinese carmakers, it manages to capture a significant market share. In contrast, Chinese emerging brands, represented by the "new forces of car making," also show strong competitiveness and dominating the market with differentiation strategies. Our counterfactual analysis suggests that the introduction of Tesla has a positive effect on consumer welfare by increasing the variety of electric vehicles available. [ABSTRACT FROM AUTHOR]

Classification of traffic signs with partial occlusions is important for traffic sign maintenance and inventory systems. It is also important to help drivers identify possible traffic signs in time. Motivated by human cognitive processes in identifying an occluded sign, a novel structure is designed to explicitly handle occluded samples in this paper. Occlusion maps are analyzed for possible occluded signs, and a new occlusion descriptor is proposed to distinguish occluded signs from negative samples. A series of tests shows that the developed method could effectively handle samples with partial occlusions and thus reduce the missed detections caused by occlusions. The developed method could also be easily used for any other object detection. [ABSTRACT FROM PUBLISHER]

The digital economy has demonstrated strong resilience and great potential, under the interwoven influence of the global pandemic and severe environmental concerns across the world. Therefore, there is a need to focus on the value of green economic growth in the digital economy. This paper constructs an evaluation index system and adopts the SEEA (System of Environmental and Economic Accounting) method to measure the digitalization level (Digi) and green economy growth level (GEG) of China. The internal mechanism and linear relationship between digitalization and green economy growth are examined based on the panel data from 2013 to 2019. Moreover, this study explores the spatial spillover effect. The major study findings are as follows: (1) Digitalization and green economy growth represent a steady growth trend, and the former as a whole significantly promotes the latter, with a marginal effect of 1.648. (2) The mechanism analysis indicates the intermediary effects' size of three crucial intermediaries: green technology innovation > advanced industrial structure > the rationalization of industrial structure. (3) Both the "local effect" (0.556; 0.574) and "neighboring effect" (1.382; 1.415) of digitalization on green economy growth are positive under the two weight matrices and display "simultaneous resonance" characteristics based on the spatial perspective. (4) There exists obvious regional spatial heterogeneity and resource endowment heterogeneity. Finally, this study put forward corresponding policy implications, such as construction of new digital infrastructures and guiding green-energy consumption. • The green economic growth (GEG) level is measured by the SEEA method. • The linear relationship shows digitalization (Digi) can significantly promote GEG. • The spatial effect of Digi on GEG shows "positive simultaneous resonance". • Three crucial intermedia's effects are compared. • The heterogeneous impact is explored from different dimensions. [ABSTRACT FROM AUTHOR]

Reassortment between different influenza viruses is a crucial way to generate novel influenza viruses with unpredictable virulence and transmissibility, which may threaten the public health. As currently in China, avian influenza viruses (AIVs) of H9N2 and H5N1 subtypes are endemic in poultry in many areas, while they are prone to reassort with each other naturally. In order to evaluate the risk of the reassortment to public health, A/Goose/Jiangsu/k0403/2010 [GS/10(H5N1)] virus was used as a backbone to generate a series of reassortants, each contained a single internal gene derived from the predominant S genotype of the A/Chicken/Jiangsu/WJ57/2012 [WJ/57(H9N2)]. We next assessed the biological characteristics of these assortments, including pathogenicity, replication efficiency and polymerase activity. We found that the parental WJ/57(H9N2) and GS/10(H5N1) viruses displayed high genetic compatibility. Notably, the H5N1 reassortants containing the PA or NP gene from WJ/57(H9N2) virus significantly increased virulence and replication ability in mice, as well as markedly enhanced polymerase activity. Our results indicate that the endemicity of H9N2 and H5N1 in domestic poultry greatly increases the possibility of generating new viruses by reassortment that may pose a great threat to poultry industry and public health. [ABSTRACT FROM AUTHOR]

Abstract: It is favorable to increase the energy efficiency of an air-cooled chiller with an efficient, reliable and cost-effective method. Coupling a direct evaporative cooler with an air-cooled condenser seems to be a feasible solution to this problem. To maximize the energy saving potential of an evaporative air-cooled chiller (EACC), which composes of an evaporative air cooler and a conventional air-cooled chiller, a mathematical model was developed and a new index, increase of seasonal energy efficiency ratio (ISEER), was proposed to evaluate the energy saving potential of the evaporative air-cooled chiller. The energy saving potential of EACC was simulated by using the hourly weather data for four typical cities in China. The impacts of various factors on the energy saving potential were analyzed and it was found that there exists an optimal pad thickness which maximizes the energy saving. The optimal pad thickness varies with climatic condition and face velocity. Optimization results of the pad thickness in 31 main cities in China are presented. The maximum energy saving potential of EACC in China is between 2.4% and 14.0% depending on the climatic condition. It is necessary to determine optimal values for the design parameters according to different climatic condition for maximum energy saving. [Copyright &y& Elsevier]

Abstract: The extraction of Ti from the simulated ilmenite sulfuric acid leachate was investigated using TRPO-kerosene extraction system. The effects of stirring rate, contact time, TRPO concentration, phase ratio, and temperature were examined. Optimized extraction conditions were found to be: 25% (v/v) TRPO in kerosene, O/A 4:1, and temperature 30°C. Under these conditions the extraction percentage of titanium was 78.5% with the extraction equilibrium and phase disengagement times of 40min and 30min, respectively. A continuous multi-stage extraction was unfeasible due to excessively long residence time. Upon the leachate being diluted by half and at the same time the sulfuric acid concentration increasing up to 150g/L, the titanium extraction significantly rose to ~96% while the co-extracted iron was ~7%. A batch operation extraction was suggested on account of still long phase disengagement time. The co-extraction of iron resulted from air oxidation of ferrous to ferric during the extraction. Under N2 atmosphere the iron extraction decreased to 1%. Thus, an almost complete titanium and iron separation was realized with a separation factor of 2367. With 1.7% (w/w) sulfuric acid, 63% of the titanium loaded in organic phase was stripped through a single contact. McCabe–Thiele analysis predicts that the number of stripping stage is at least 5 under O/A phase ratio of 1:5 of operation line if a 90% of titanium stripping can be obtained. Further study showed that the extracted titanium species possibly included TiOSO4·TRPO besides TiO(HSO4)2·2TRPO under the conditions of high titanium ion concentration and relatively low concentrations of sulfuric acid and TRPO. [Copyright &y& Elsevier]

Abstract: Endoreversible Joule–Brayton cogeneration cycle has been optimized based on a new criterion, total useful energy-rate (including power output and useful heat output), and the efficiency at maximum total useful energy rate has also been determined. The effects of various cycle parameters on the maximum dimensionless total useful-energy rate and the efficiency at maximum total useful-energy rate have been assessed. Variations of dimensionless total useful-energy rate with respect to efficiency have also been analyzed. The reversible Joule–Brayton power cycle is a special case of the analyzed cycle. [Copyright &y& Elsevier]

Abstract: During last century, worldwide environment degradation gets more and more serious, and achieving environmental sustainable development is desirable. As many environmental issues are directly or indirectly energy related, energy sustainable development is one of the most important prerequisites for environmental sustainable development. Renewable energy technologies and energy conservation are two solutions for energy sustainable development. At present, energy-saving technology is a feasible and an effective way to achieve energy and environmental sustainable development, although renewable energy may be final solution to environmental issues. Building cooling, heating, and power (BCHP) technology, which usually use natural gas as primary energy, has high efficiency of energy utilization due to the utilization of distributed power generation and heat recovery, and thus is a promising energy conservation technology. BCHP can reduce pollutants emission and thus protects the environment besides improving IAQ and increasing reliability of building energy supply. As the largest developing country, China is just in the process of adjusting energy structure and improving energy efficiency. Because of its significant role in energy and environmental sustainable development, developing BCHP in China will help the country in optimizing energy proportion, increasing energy efficiency, and protecting environment. Therefore, BCHP technology will have broad prospects in China and it will promote the country''s energy and environmental sustainable development. [Copyright &y& Elsevier]

Abstract: This paper presents an approach to isolate flow meter faults in building central chilling systems. It mathematically explains the fault collinearity among the flow meters in central chilling systems and points out that the sensor validation index (SVI) used in principal component analysis (PCA) is incapable of isolating flow meter faults due to the fault collinearity. The wavelet transform is used to isolate the flow meter faults as a substitute for the SVI of PCA. This approach can identify various variations in measuring signals, such as ramp, step, discontinuity etc., due to the good property of the wavelet in local time–frequency. Some examples are given to demonstrate its ability of fault isolation for the flow meters. [Copyright &y& Elsevier]

It is necessary that a reliable and optimal control system has the ability of fault tolerance, which recovers the faulty and/or missed data in time. Principal component analysis (PCA) is presented to model HVAC monitored systems by using the measured data under normal operation condition (NOC). PCA splits the measurement space into two subspaces, one principal component subspace (PCS) and the other residual subspace (RS). When the faulty or missed data is observed, it will be projected into PCS and RS. It is then recovered by sliding the faulty or missed data to PCS via iteration. Examples of HVAC monitoring system have demonstrated that the approach has good performance to recover faulty or missed data and thus can be embedded into the system to achieve fault-tolerant control. [Copyright &y& Elsevier]

Widespread bacterial infection and the spread of antibiotic resistance exhibit increasing threat to the public and thus require new antibacterial strategies. Carbon quantum dots (CQDs) have been extensively investigated to play fluorescent, catalytic roles and even potential biomedical functions containing sterilization. However, synthetic understanding of the interaction of CQDs and bacteria, the exhibition of antibacterial ability, and the risk of resistance evolution remain lacking. Herein, a simple one-pot method was fabricated to prepare positively charged CQDs (PC-CQDs) as a broad-spectrum antibacterial agent. PC-CQDs possessed effective antibacterial activity against all tested Gram-positive, Gram-negative, and drug-resistant bacteria. Investigation of the antibacterial mechanism of PC-CQDs indicated that small-sized PC-CQDs functionalized with –NH 2 and –NH induced strong adherence behavior on the bacterial cell membrane. Moreover, the entry of PC-CQDs caused conformational changes in the genes and generation of reactive oxygen species in the bacteria. Safety evaluation illustrated that PC-CQDs did not trigger detectable drug resistance or hemolysis. Furthermore, PC-CQDs effectively promoted the antibacterial treatment of mixed Staphylococcus aureus and Escherichia coli infected wound in rats with low in vivo toxicity. These results suggested that PC-CQDs are a potential antibacterial candidate for real wound healing applications in complex bacterial infections and even resistant bacteria-caused infections. • A simple one-pot method was fabricated for positively charged CQDs (PC-CQDs). • PC-CQDs possessed effective broad-spectrum antibacterial activity including drug-resistant bacteria. • The antibacterial properties of PC-CQDs come from the process of absorption, permeation and intracellular action. • PC-CQDs did not trigger detectable antimicrobial resistance or hemolysis. • PC-CQDs exhibited the antibacterial treatment of mixed S. aureus and E. coli infected wound. [ABSTRACT FROM AUTHOR]

Avian influenza virus (AIV) emerged and has continued to re-emerge, continuously posing great threats to animal and human health. The detection of hemagglutination inhibition (HI) or virus neutralization antibodies (NA) is essential for assessing immune protection against AIV. However, the HI/NA-independent immune protection is constantly observed in vaccines' development against H7N9 subtype AIV and other subtypes in chickens and mammals, necessitating the analysis of the cellular immune response. Here, we established a multi-parameter flow cytometry to examine the innate and adaptive cellular immune responses in chickens after intranasal infection with low pathogenicity H7N9 AIV. This assay allowed us to comprehensively define chicken macrophages, dendritic cells, and their MHC-II expression, NK cells, γδ T cells, B cells, and distinct T cell subsets in steady state and during infection. We found that NK cells and KUL01+ cells significantly increased after H7N9 infection, especially in the lung, and the KUL01+ cells upregulated MHC-II and CD11c expression. Additionally, the percentages and numbers of γδ T cells and CD8 T cells significantly increased and exhibited an activated phenotype with significant upregulation of CD25 expression in the lung but not in the spleen and blood. Furthermore, B cells showed increased in the lung but decreased in the blood and spleen in terms of the percentages or/and numbers, suggesting these cells may be recruited from the periphery after H7N9 infection. Our study firstly disclosed that H7N9 infection induced local and systemic cellular immune responses in chickens, the natural host of AIV, and that the flow cytometric assay developed in this study is useful for analyzing the cellular immune responses to AIVs and other avian infectious diseases and defining the correlates of immune protection. [ABSTRACT FROM AUTHOR]

• The monitor of chondroitin sulfate (CS) in synovial fluid and drug is important and demanded. • A ratiometric fluorescence assay based on positively charged nitrogen doped carbon dots and ssDNA was developed for CS. • The ratios of the fluorescence intensities for CS detection can be obtained through synchronous fluorescence spectrometry. • The assay showed a good linear relationship, low detection limit and excellent selectivity for CS. • This method successfully tested CS in synovial fluid and drug. Chondroitin sulfate (CS) plays an increasingly important role in clinical settings and pharmacy quality control. However, sensitive and simple methods for CS detection remain limited. In this work, positively charged nitrogen doped carbon dots (P-NCDs) with internal luminescence and quenching property to FAM-labeled random-sequence ssDNA (F-ssDNA) were prepared by a simple heating method. P-NCDs attached and quenched F-ssDNA through electrostatic interaction to form the system of P-NCDs and F-ssDNA (P-NCDs/F-ssDNA) with retained fluorescence intensity of P-NCDs. The highly negatively charged CS reacted electrostatically with P-NCDs and then replaced F-ssDNA in P-NCDs/F-ssDNA to recover the fluorescence intensity of the original quenched F-ssDNA while retaining the internal fluorescence intensity of P-NCDs. Thus, by using restored F-ssDNA as the signal controlled by adding CS to P-NCDs/F-ssDNA, a ratiometric fluorescence strategy based on the retained fluorescence of P-NCDs as reference signal was fabricated through synchronous fluorescence spectrometry for the sensitive detection of CS. Under the optimal experimental conditions, a linear equation for CS was obtained for CS concentration within the range of 0.05–2.0 μg/mL. The method was also successfully applied for the accurate determination of CS in joint fluid samples of arthritic patients, chondroitin sulfate tablets, and chondroitin sulfate eye drops, suggesting its appreciable application potential in the clinic. [ABSTRACT FROM AUTHOR]

Heat treatment is the most common method used to make milk safe; however, it leads to changes in the organoleptic and nutritional properties of milk. This study aimed to investigate the effects of different heat treatments on nutrients and microbiota of camel milk. The results showed that the nutrient composition of camel milk could be influenced by heat treatment. Ultra-high-temperature treatment of samples significantly reduced levels of camel milk proteins, vitamin C, and lactose, but did not significantly alter the amino acids content. Analysis of 16S rRNA amplicon sequences demonstrated that the composition of the intestinal microbiota of mice fed different heat-treated camel milks changed, as did the production of short-chain fatty acids as determined by gas chromatography–mass spectrometry. High temperature/short time treatment had similar effects to UHT treatment on microbial diversity of camel milk; however, the low temperature/long time treatment had different effects. In addition, higher-temperature treatments changed the abundance of key bacteria at the genus level. These results demonstrated that different heat treatments not only resulted in some nutrient loss, but also changed the proliferation of some probiotic genera. Our results could provide the basis for the potential industrial application of camel milk processing technologies. [ABSTRACT FROM AUTHOR]

Marek's disease virus (MDV) is a highly oncogenic alphaherpesvirus that causes deadly T-cell lymphomas and serves as a natural virus-induced tumor model in chickens. Although Marek's disease (MD) is well controlled by current vaccines, the evolution of MDV field viruses towards increasing virulence is concerning as a better vaccine to combat very virulent plus MDV is still lacking. Our understanding of molecular and cellular immunity to MDV and its immunopathogenesis has significantly improved, but those findings about cellular immunity to MDV are largely out-of-date, hampering the development of more effective vaccines against MD. T-cell-mediated cellular immunity was thought to be of paramount importance against MDV. However, MDV also infects macrophages, B cells and T cells, leading to immunosuppression and T-cell lymphoma. Additionally, there is limited information about how uninfected immune cells respond to MDV infection or vaccination, specifically, the mechanisms by which T cells are activated and recognize MDV antigens and how the function and properties of activated T cells correlate with immune protection against MDV or MD tumor. The current review revisits the roles of each immune cell subset and its effector mechanisms in the host immune response to MDV infection or vaccination from the point of view of comparative immunology. We particularly emphasize areas of research requiring further investigation and provide useful information for rational design and development of novel MDV vaccines. [ABSTRACT FROM AUTHOR]

The expression level of miRNA-21 is closely related to the occurrence and development of cancer, especially in gastrointestinal cancer. Monitoring miRNA-21 has clinical application in the diagnosis and evaluation of gastrointestinal cancer. A turn-on ratiometric fluorescence bioassay based on the T7 exonuclease-mediated cyclic enzymatic amplification method was developed for miRNA-21 determination by using carbon dots (CDs) and FAM-labeled ssDNA as the signal source. CDs demonstrated the triple functions of built-in internal fluorescence, probe carrier, and quencher in this strategy. In the absence of miRNA-21, FAM-labeled ssDNA would be adsorbed and quenched by CDs. The addition of miRNA-21 induced cycle hydrolysis from the 5′ end by the T7 exonuclease and then released the short-cleaved FAM-labeled oligonucleotides. Then, the increased FAM signal (F FAM) and the stable CD signal (F CDs) would be tested through a ratiometric routine for the quantification of miRNA-21. The F FAM /F CDs value showed a good linear relationship with the concentration of miRNA-21 in the range of 0.05–10 nM, and the detection limit for miRNA-21 was 1 pM with excellent selectivity and reproducibility. Furthermore, this sensor successfully evaluated the expression level of miRNA-21 in clinical blood samples from healthy individuals and gastrointestinal cancer patients, and the results were highly consistent with those of qRT-PCR, suggesting the great clinical application value in the diagnosis of cancer associated with miRNA-21 expression levels. Image 1 • A turn-on ratiometric fluorescence bioassay based on the T7 exonuclease and carbon dots (CDs) was developed for miRNA-21. • CDs demonstrated the triple functions of built-in internal fluorescence, probe carrier, and quencher in this strategy. • The assay showed a good linear relationship with low detection limit, excellent selectivity and reproducibility for miRNA-21. • The expression level of miRNA-21 is closely related to the occurrence and development of gastrointestinal cancer. • This method successfully evaluated miRNA-21 in clinical blood samples in accord with the results from qRT-PCR. [ABSTRACT FROM AUTHOR]

Highlights • Extensively evaluate pixel-level image fusion based on CNN pedestrian detectors. • Study effective methods to combine pixel-level fusion and CNN-fusion architectures. • Three state-of-the-art CNN-based object detectors are evaluated. Abstract Vision-based pedestrian detection that can last all day is crucial in advanced driver-assistance systems (ADAS), autonomous vehicles and video surveillance. Based on the fact that the wavelength of human body radiation falls around 9.3 μm, thermal images have distinctive advantages for pedestrian detection in the nighttime. With the recent success of convolutional neural networks (CNNs) in the vision community, how to properly explore information in color and thermal images using CNNs-based methods attracts the attention of researchers. Previous CNN-based multispectral pedestrian detectors focus on the design of network architectures. The main contributions of this paper are as follows. First, pixel-level image fusion are also extensively evaluated based on a state-of-the-art CNNs-based framework in the daytime and nighttime for pedestrian detection. Second, the effective strategies to combine pixel-level fusion methods and CNN-fusion architectures are studied based on extensive experimental results. Two combination strategies are designed and an exhaustive experimental analysis is performed to evaluate different combinations for all-day pedestrian detection. Extensive results based on a multispectral pedestrian benchmark show that some pixel-level image fusion methods can achieve similar or even better performance than CNN-fusion architectures, which emphasizes the importance of pixel-level fusion in CNN-based pedestrian detectors. The combination of both can usually more properly exploit multispectral information and further boost detection performance. [ABSTRACT FROM AUTHOR]

Bond transition of sp2 to sp3 in carbon nanotube can be realized through bending operation at buckling location, which affects the electronic, mechanical and thermal properties of buckled carbon nanotube. In this work, thermal properties of buckled tri-walled carbon nanotube with sp3 bonds are explored using molecular dynamics. Our results reveal that interfacial thermal conductance at buckling location is sensitive to the bending angle, which decreases exponentially with increasing bending angle until 90 degree because of increasing the number of interlayer sp3 bonds. When the bending angle is beyond 90 degree, there are sp3 bonds formed on the outer-tube walls which provide new paths for heat transfer. The insight of mechanism of thermal properties is analyzed by determining atomic micro-heat flux scattering. Our findings provide a flexible and applicable method to design thermal management device. This unusual phenomenon is explained by the micro-heat flux migration and stress distributions. [ABSTRACT FROM AUTHOR]

The majority of the existing appearance-based vehicle-detection systems make use of local features for detection purposes, such as Haar-like, histograms of oriented gradients, scale-invariant feature transform, and so forth. However, these local features have limitations when dealing with illuminations, scale, shape variations, and complex background situations. It is desirable for a vehicle to have discriminative and robust features. For this purpose, a novel context-aware multichannel feature pyramid has been proposed in this paper. The main contribution of this paper is proposing two context-aware structural descriptors, termed as a context-aware difference sign transform feature and context-aware difference magnitude transform feature. An image has been tiled with a dense grid of the cells, and each cell is described by both local details and context-aware structural descriptors. The context-aware structural descriptors have the ability to capture the context-aware structural information of cells. The proposed context-aware multichannel feature pyramid is able to provide more effective features for vehicle detection. The results of the two public traffic analysis datasets show that the proposed approach leads to better performances when compared with the current state-of-the-art methods. Moreover, the experimental results are determined to be satisfactory, even for the images containing vehicles that have undergone scale variations and camera viewpoint changes, as well as for images that were photographed with complex backgrounds. [ABSTRACT FROM AUTHOR]

Aim: The associations of non‐pathogenic variants of APP, PSEN1, and PSEN2 with Alzheimer's disease (AD) remain unclear. This study is aimed at determining the role of these variants in AD. Methods: Our study recruited 1154 AD patients and 2403 controls. APP, PSEN1, PSEN2, and APOE were sequenced using a targeted panel. Variants were classified into common or rare variants with the minor allele frequencies (MAF) cutoff of 0.01. Common variant (MAF≥0.01)‐based association test was performed by PLINK 1.9, and gene‐based (MAF <0.01) association analysis was conducted using Sequence Kernel Association Test‐Optimal (SKAT‐O test). Additionally, using PLINK 1.9, we performed AD endophenotypes association studies. Results: A common variant, PSEN2 rs11405, was suggestively associated with AD risk (p = 1.08 × 10−2). The gene‐based association analysis revealed that the APP gene exhibited a significant association with AD (p = 1.43 × 10−2). In the AD endophenotypes association studies, APP rs459543 was nominally correlated with CSF Aβ42 level (p = 7.91 × 10−3). Conclusion: Our study indicated that non‐pathogenic variants in PSEN2 and APP may be involved in AD pathogenesis in the Chinese population. [ABSTRACT FROM AUTHOR]

Aims: We mainly evaluate retinal alterations in Alzheimer's disease (AD) patients, investigate the associations between retinal changes with AD biomarkers, and explore an optimal machine learning (ML) model for AD diagnosis based on retinal thickness. Methods: A total of 159 AD patients and 299 healthy controls were enrolled. The retinal parameters of each participant were measured using optical coherence tomography (OCT). Additionally, cognitive impairment severity, brain atrophy, and cerebrospinal fluid (CSF) biomarkers were measured in AD patients. Results: AD patients demonstrated a significant decrease in the average, superior, and inferior quadrant peripapillary retinal nerve fiber layer, macular retinal nerve fiber layer, ganglion cell layer (GCL), inner plexiform layer (IPL) thicknesses, as well as total macular volume (TMV) (all p < 0.05). Moreover, TMV was positively associated with Mini‐Mental State Examination and Montreal Cognitive Assessment scores, IPL thickness was correlated negatively with the medial temporal lobe atrophy score, and the GCL thickness was positively correlated with CSF Aβ42/Aβ40 and negatively associated with p‐tau level. Based on the significantly decreased OCT variables between both groups, the XGBoost algorithm exhibited the best diagnostic performance for AD, whose four references, including accuracy, area under the curve, f1 score, and recall, ranged from 0.69 to 0.74. Moreover, the macular retinal thickness exhibited an absolute superiority for AD diagnosis compared with other enrolled variables in all ML models. Conclusion: We identified the retinal alterations in AD patients and found that macular thickness and volume were associated with AD severity and biomarkers. Furthermore, we confirmed that OCT combined with ML could serve as a potential diagnostic tool for AD. [ABSTRACT FROM AUTHOR]

The majority of existing traffic sign detection systems utilize color or shape information, but the methods remain limited in regard to detecting and segmenting traffic signs from a complex background. In this paper, we propose a novel graph-based traffic sign detection approach that consists of a saliency measure stage, a graph-based ranking stage, and a multithreshold segmentation stage. Because the graph-based ranking algorithm with specified color and saliency combines the information of color, saliency, spatial, and contextual relationship of nodes, it is more discriminative and robust than the other systems in terms of handling various illumination conditions, shape rotations, and scale changes from traffic sign images. Furthermore, the proposed multithreshold segmentation algorithm focuses on all the nodes with a nonzero ranking score, which can effectively solve problems such as complex background, occlusion, various illumination conditions, and so on. The results for three public traffic sign sets show that our proposed approach leads to better performance than the current state-of-the-art methods. Moreover, the results are satisfactory even for images containing traffic signs that have been rotated or undergone occlusion, as well as for images that were photographed under different weather and illumination conditions. [ABSTRACT FROM PUBLISHER]

Background: Some previous studies showed abnormal pathological and vascular changes in the retina of patients with Alzheimer's disease (AD). However, whether retinal microvascular density is a diagnostic indicator for AD remains unclear.Objective: This study evaluated the macular vessel density (m-VD) in the superficial capillary plexus and fovea avascular zone (FAZ) area in AD, explored their correlations with clinical parameters, and finally confirmed an optimal machine learning model for AD diagnosis.Methods: 77 patients with AD and 145 healthy controls (HCs) were enrolled. The m-VD and the FAZ area were measured using optical coherence tomography angiography (OCTA) in all participants. Additionally, AD underwent neuropsychological assessment, brain magnetic resonance imaging scan, cerebrospinal fluid (CSF) biomarker detection, and APOE ɛ4 genotyping. Finally, the performance of machine learning algorithms based on the OCTA measurements was evaluated by Python programming language.Results: The m-VD was noticeably decreased in AD compared with HCs. Moreover, m-VD in the fovea, superior inner, inferior inner, nasal inner subfields, and the whole inner ring declined significantly in mild AD, while it was more serious in moderate/severe AD. However, no significant difference in the FAZ was noted between AD and HCs. Furthermore, we found that m-VD exhibited a significant correlation with cognitive function, medial temporal atrophy and Fazekas scores, and APOE ɛ4 genotypes. No significant correlations were observed between m-VD and CSF biomarkers. Furthermore, results revealed the Adaptive boosting algorithm exhibited the best diagnostic performance for AD.Conclusion: Macular vascular density could serve as a diagnostic biomarker for AD. [ABSTRACT FROM AUTHOR]

Objectives: CYLD was a novel causative gene for frontotemporal dementia (FTD) and amyotrophic lateral sclerosis. Given the clinical and pathological overlap of FTD and Alzheimer's disease (AD), it is necessary to screen CYLD in AD patients and FTD patients in the Chinese population. Methods: In our study, using a targeted sequencing panel, we sequenced the CYLD gene in a large cohort of 2485 participants in the Chinese population, including 1008 AD patients, 105 FTD patients, and 1372 controls. Results: In the present study, the average onset age of AD and FTD patients was 66.84 ± 30.42 years old and 60 ± 10.00 years old, respectively. Our study reported three novel CYLD variants: p.Phe288Leu (patient No. 1, AD), p.Tyr485Phe (patients No. 6–9, all AD) and p.Thr951Ala (patient No. 10, AD), plus a previously reported variant: p.Arg397Ser (patient No. 2–5, AD and No. 11, FTD). These variants were absent in our in‐house controls and predicted to be deleterious according to the MutationTaster. The variant carriers were composed of 10 AD patients and one FTD patient, and the average onset age was 61.2 ± 10.9 years. The frequency of CYLD variants in AD was similar to that in FTD, which was 0.99% (10/1008) and 0.95% (1/105), respectively. Interpretation: Our finding extended the genotype and phenotype of the CYLD gene and demonstrated that CYLD rare damaging variants may be implicated in AD and FTD pathogenesis. [ABSTRACT FROM AUTHOR]

In this paper, a semi-nested building coupled with an earth-to-air heat exchanger is investigated to maintain indoor thermal comfort and reduce building energy consumption. Firstly, the computer models on the semi-nested building coupled with earth-to-air heat exchanger were developed under the TRNSYS environment. Secondly, the simulation results from the computer models were validated with experimental data from open literature. Finally, iterative Targuchi method was employed to find the optimal design values for the envelope properties and earth-to-air heat exchanger configurations. The optimal values of the design parameters were found to be A1 (window-to-wall ratio of 10%), B3 (triple-layer Low-E glazing window), C3(insulation thickness of 200 mm for external wall),D3 (concrete slab thickness of 250 mm for external wall), E3(absorption of solar radiation for external walls of 0.75), F3(absorption of solar radiation for the roof of 0.75),G5 (earth tube inner diameter and air gap of 300 mm and 400 mm, respectively), H2 (earth tube length of 50 m), and I3 (duct air velocity of 1.5 m/s). [ABSTRACT FROM AUTHOR]

Despite the similar clinical and pathological features between Niemann-Pick type C (NPC) disease and Alzheimer's disease (AD), few studies have investigated the role of NPC genes in AD. To elucidate the role of NPC genes in AD, we sequenced NPC1 and NPC2 in 1192 AD patients and 2412 controls. Variants were divided into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF≥0.01) based association analysis was conducted by PLINK 1.9. Gene-based aggregation testing of rare variants was performed by Sequence Kernel Association Test-Optimal (SKAT-O test), respectively. Age at onset (AAO) and mini-mental state examination (MMSE) association studies were also performed with PLINK 1.9. Six common variants were identified and exhibited no association with AD. Gene-based aggregation testing revealed that both NPC1 and NPC2 were not associated with AD risk. Additionally, AAO and MMSE association studies revealed that no common variants were linked with AD endophenotypes. Taken together, our study indicated that NPC1 and NPC2 may not be implicated in AD pathogenesis in the Chinese population. [ABSTRACT FROM AUTHOR]

The CD69 molecule, as an early activation marker of lymphocytes, is often used to assess the activation of cellular immunity. However, for pigs, an anti-pig CD69 antibody is not yet available for this purpose after infection or vaccination. In this study, a monoclonal antibody (mAb) against pig CD69 was produced by peptide immunization and hybridoma technique. One mAb (5F12) showed good reactivity with pig CD69 that was expressed in transfected-HEK-293T cells and on mitogen-activated porcine peripheral blood mononuclear cells (PBMCs) by indirect immunofluorescence assay and flow cytometry. This mAb did not cross-react with activated lymphocytes from mouse, bovine, and chicken. Epitope mapping showed that the epitope recognized by this mAb was located at amino acid residues 147–161 of pig CD69. By conjugating with fluorochrome, this mAb was used to detect the early activation of lymphocytes in PRRSV- and ASFV-infected pigs by flow cytometry. The results showed that PRRSV infection induced the dominant activation of CD4 T cells in mediastinal lymph nodes and CD8 T cells in the spleen at 14 days post-infection, in terms of CD69 expression. In an experiment on ASFV infection, we found that ASFV infection resulted in the early activation of NK cells, B cells, and distinct T cell subsets with variable magnitude in PBMCs, spleen, and submandibular lymph nodes. Our study revealed an early event of lymphocyte and T cell activation after PRRSV and ASFV infections and provides an important immunological tool for the in-depth analysis of cellular immune response in pigs after infection or vaccination. [ABSTRACT FROM AUTHOR]

Reassortment with the H9N2 virus gave rise to the zoonotic H7N9 avian influenza virus (AIV), which caused more than five outbreak waves in humans, with high mortality. The frequent exchange of genomic segments between H7N9 and H9N2 has been well-documented. However, the reassortment patterns have not been described and are not yet fully understood. Here, we used phylogenetic analyses to investigate the patterns of intersubtype and intrasubtype/intralineage reassortment across the eight viral segments. The H7N9 virus and its progeny frequently exchanged internal genes with the H9N2 virus but rarely with the other AIV subtypes. Before beginning the intrasubtype/intralineage reassortment analyses, five Yangtze River Delta (YRD A-E) and two Pearl River Delta (PRD A-B) clusters were divided according to the HA gene phylogeny. The seven reset segment genes were also nomenclatured consistently. As revealed by the tanglegram results, high intralineage reassortment rates were determined in waves 2–3 and 5. Additionally, the clusters of PB2 c05 and M c02 were the most dominant in wave 5, which could have contributed to the onset of the largest H7N9 outbreak in 2016–2017. Meanwhile, a portion of the YRD-C cluster (HP H7N9) inherited their PB2, PA, and M segments from the co-circulating YRD-E (LP H7N9) cluster during wave 5. Untanglegram results revealed that the reassortment rate between HA and NA was lower than HA with any of the other six segments. A multidimensional scaling plot revealed a robust genetic linkage between the PB2 and PA genes, indicating that they may share a co-evolutionary history. Furthermore, we observed relatively more robust positive selection pressure on HA, NA, M2, and NS1 proteins. Our findings demonstrate that frequent reassortment, particular reassorted patterns, and adaptive mutations shaped the H7N9 viral genetic diversity and evolution. Increased surveillance is required immediately to better understand the current state of the HP H7N9 AIV. [ABSTRACT FROM AUTHOR]

Aim: The role of vascular dementia (VaD)‐associated genes in Alzheimer's disease (AD) remains elusive despite similar clinical and pathological features. We aimed to explore the relationship between these genes and AD in the Chinese population. Methods: Eight VaD‐associated genes were screened by a targeted sequencing panel in a sample of 3604 individuals comprising 1192 AD patients and 2412 cognitively normal controls. Variants were categorized into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF ≥ 0.01)‐based association analysis was conducted by PLINK 1.9. Rare variant (MAF < 0.01) association study and gene‐based aggregation testing of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test‐Optimal (SKAT‐O test), respectively. Age at onset (AAO) and Mini‐Mental State Examination (MMSE) association studies were performed with PLINK 1.9. Analyses were adjusted for age, gender, and APOE ε4 status. Results: Four common COL4A1 variants, including rs874203, rs874204, rs16975492, and rs1373744, exhibited suggestive associations with AD. Five rare variants, NOTCH3 rs201436750, COL4A1 rs747972545, COL4A1 rs201481886, CST3 rs765692764, and CST3 rs140837441, showed nominal association with AD risk. Gene‐based aggregation testing revealed that HTRA1 was nominally associated with AD. In the AAO and MMSE association studies, variants in GSN, ITM2B, and COL4A1 reached suggestive significance. Conclusion: Common variants in COL4A1 and rare variants in HTRA1, NOTCH3, COL4A1, and CST3 may be implicated in AD pathogenesis. Besides, GSN, ITM2B, and COL4A1 are probably involved in the development of AD endophenotypes. [ABSTRACT FROM AUTHOR]

Wolbachia are maternally transmitted intracellular bacteria that can naturally and artificially infect arthropods and nematodes. Recently, they were applied to control the spread of mosquito-borne pathogens by causing cytoplasmic incompatibility (CI) between germ cells of females and males. The ability of Wolbachia to induce CI is based on the prevalence and polymorphism of Wolbachia in natural populations of mosquitoes. In this study, we screened the natural infection level and diversity of Wolbachia in field-collected mosquitoes from 25 provinces of China based on partial sequence of Wolbachia surface protein (wsp) gene and multilocus sequence typing (MLST). Among the samples, 2489 mosquitoes were captured from 24 provinces between July and September, 2014 and the remaining 1025 mosquitoes were collected month-by-month in Yangzhou, Jiangsu province between September 2013 and August 2014. Our results showed that the presence of Wolbachia was observed in mosquitoes of Aedes albopictus (97.1%, 331/341), Armigeres subalbatus (95.8%, 481/502), Culex pipiens (87.0%, 1525/1752), Cx. tritaeniorhynchus (17.1%, 14/82), but not Anopheles sinensis (n = 88). Phylogenetic analysis indicated that high polymorphism of wsp and MLST loci was observed in Ae. albopictus mosquitoes, while no or low polymorphisms were in Ar. subalbatus and Cx. pipiens mosquitoes. A total of 12 unique mutations of deduced amino acid were identified in the wsp sequences obtained in this study, including four mutations in Wolbachia supergroup A and eight mutations in supergroup B. This study revealed the prevalence and polymorphism of Wolbachia in mosquitoes in large-scale regions of China and will provide some useful information when performing Wolbachia-based mosquito biocontrol strategies in China. Author summary: The mosquitoes Aedes albopictus, Anopheles sinensis, Armigeres subalbatus, Culex pipiens and Cx. tritaeniorhynchus are native to China and the major vectors in the transmission of arboviruses, protozoans and nematodes. Recently, an innovative biocontrol strategy has been developed and evaluated based on the ability of Wolbachia to induce cytoplasmic incompatibility (CI), as well as interfere with the infection and replication of pathogens. Since the ability to induce CI largely depends on the density and diversity of Wolbachia, we investigated and characterized the natural infection of Wolbachia in above-mentioned five species of field-collected mosquitoes in 25 provinces of China. The results showed that the positive rates of Wolbachia infection were high in mosquitoes of Ae. albopictus, Ar. subalbatus and Cx. pipiens in large-scale regions of China and low in Cx. tritaeniorhynchus in Guizhou province. Phylogenetic analysis based on Wolbachia surface protein (wsp) gene and five multilocus sequence typing (MLST) loci indicated the high polymorphism of Wolbachia in Ae. albopictus, and low polymorphisms in Ar. subalbatus and Cx. pipiens. This finding contributes to the understanding of the nationwide distribution of Wolbachia and the potential application of this biocontrol strategy in China. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) involves four electron transfer processes and is of great significance in water electrolysis. The development of efficient and robust non-precious OER electrocatalysts remains a critical challenge for the production, storage and conversion of renewable energy. Herein, vertically NiCo 2 O 4 nanosheets are grown on Ti mesh via a facile solvothermal method which is followed by low-temperature calcination. The NiCo 2 O 4 /Ti catalyst exhibits outstanding OER performance with a low overpotential of 353 mV to drive the current density of 10 mA cm−2 and a Tafel slope of 61 mV dec−1 in alkaline solution. Moreover, the stable electrocatalyst undergoes negligible degradation in alkaline media at least 20 h. The acceleration of the electrochemical OER likely stems from the facile electron transfer promoted by the NiCo 2 O 4 /Ti interface as revealed by X-ray photoelectron spectroscopy. This work introduces a novel strategy for the establishment low-cost electrocatalysts for electrochemical water splitting. Electronic and Structural Engineering: The optimal NiCo 2 O 4 /Ti heterostructured catalyst demonstrates remarkable OER performance and long-term durability. This research provides a useful strategy of electronic and structural engineering to develop highly efficient non-noble-based electrocatalysts for water spitting and other energy conversion processes.. Image 1 • The NiCo 2 O 4 /Ti heterostructure demonstrates remarkable OER performance. • The NiCo 2 O 4 /Ti delivers the 10 mA cm-2 at overpotential as low as 353 mV. • The research provides an useful electronic and structural engineering for OER. [ABSTRACT FROM AUTHOR]

Background: Genotype S H9N2 viruses have become predominant in poultry in China since 2010. These viruses frequently donate their whole internal gene segments to other emerging influenza A subtypes such as the novel H7N9, H5N6, and H10N8 viruses. We recently reported that the PB2 and M genes of the genotype S H9N2 virus, which are derived from the G1-like virus, enhance the fitness of H5Nx and H7N9 avian influenza viruses in chickens and mice. However, whether the G1-like PB2 and M genes are preferentially incorporated into progeny virions during virus reassortment remains unclear; whether the G1-like PB2 and M genes from different subtypes are differentially incorporated into new virion progeny remains unknown. Results: We conducted a reassortment experiment with the use of a H7N9 virus as the backbone and found that G1-like M/PB2 genes were preferentially incorporated in progeny virions over F/98-like M/PB2 genes. Importantly, the preference varied among G1-like M/PB2 genes of different subtypes. When competing with F/98-like M/PB2 genes during reassortment, both the M and PB2 genes from the H7N9 virus GD15 showed an advantage, whereas only the PB2 gene from the H9N2 virus CZ73 and the M gene from the H9N2 virus AH320 displayed the advantage. Conclusion: Our findings highlight the preferential and variable advantages of H9N2-derived G1-like M and PB2 genes in incorporating them into H7N9 progeny virions over SH14-derived F/98-like M/PB2 genes. [ABSTRACT FROM AUTHOR]

Panax ginseng C. A. Meyer is a desirable medicinal plant due to its health benefits. With the growing interest in ginseng products, the safe preservation of genetically engineered material with unique attributes is increasingly important. In the present study, an effective protocol for cryopreservation of the ginseng embryogenic callus by vitrification is reported. After 2-wk subculture, the calluses were cold-acclimated at 4°C for 3 wk, then precultured for 2 d with a preculture medium containing 0.3 M sucrose. The precultured embryonic callus was then treated with a loading solution, followed by exposure to plant vitrification solution 2 at 0°C for 90 min. The dehydrated embryogenic calluses were then transferred into fresh 1.5 mL plant vitrification solution 2 and directly immersed in liquid nitrogen. With this protocol, an average of 68.3% regrowth rate for cryopreserved material was obtained, and the number of somatic embryos differentiated from embryogenic callus was significantly increased. Proteomic analysis showed that proteins related to carbohydrate metabolism, the stress response, and oxidative metabolism all significantly up-regulated after cryopreservation. Our results indicate that cold acclimation and preculture may be linked to enhanced cryopreservation tolerance. The up-regulated proteins play an important role in ginseng stress responses and may contribute to cryopreservation tolerance. Carbohydrate metabolism–related protein may be associated with the recovery growth of the cryopreserved embryogenic callus. The increased expression of HSP and 14-3-3-like protein play important roles in the response to stress and could be related with the improvement of somatic embryo production after cryopreservation. [ABSTRACT FROM AUTHOR]

Real-time 3D object detection is a fundamental technique in numerous applications, such as autonomous driving, unmanned aerial vehicles (UAV) and robot vision. However, current LiDAR-based 3D object detection algorithms allocate inadequate attention to the inhomogeneity of LiDAR point clouds and the shape encoding capability of regional proposal schemes. This paper introduces a novel 3D object detection network called the Shape Attention Regional Proposal Network (SARPNET), which deploys a new low-level feature encoder to remedy the sparsity and inhomogeneity of LiDAR point clouds with an even sample method, and embodies a shape attention mechanism that learns the statistic 3D shape priors of objects and uses them to spatially enhance semantic embeddings. Experimental results show that the proposed one-stage method outperforms state-of-the-art one-stage and even two-stage methods on the KITTI 3D object detection benchmark. It achieved a BEV AP of (87.26%, 62.80%), 3D AP of (75.64%, 60.43%), and orientation AP of (88.86%, 71.01%) for the detection of cars and cyclists, respectively. Besides, the method is the third winner in the nuScenes 3D Detection challenge of CVPR2019 Workshop on Autonomous Driving (WAD). [ABSTRACT FROM AUTHOR]

• DA was devised as a new substrate for ACP enzymatic catalysis for the fluorescent monitor of ACP. • ACP could induce DA to form polydopamine under acidic and neutral conditions. • The formed polydopamine quenches carbon dots effectively through the IFE. • The sensitive assay could differentiate ACP from ALP well under neutral condition. Detection of acid phosphatase (ACP), a universal and important enzyme, is crucial in monitoring several diseases. However, the selectivity of ACP detection under neutral conditions is poor. Herein, ACP was found to catalyze dopamine as a new substrate to polydopamine in acidic or neutral conditions, whereas alkaline phosphatase (ALP) failed to serve such function. The catalytic mechanism underlying the formation of polydopamine was investigated. A simple assay for ACP was developed using fluorescent carbon dots as a signal indicator. In the presence of ACP, dopamine polymerization was conducted in situ and carbon dots were quenched through the inner filter effect. This fluorescent bioassay illustrated a good analytical performance with a wide linear range and a detection limit of 0.45 U/L. In particular, ACP showed high selectivity from the interference of ALP under neutral conditions. Furthermore, excellent test recovery in human serum samples demonstrated the predictable applications of this method in clinical and biomedical areas. [ABSTRACT FROM AUTHOR]

Interleukin-9 receptor alpha chain (IL-9Rα) is the ligand-binding subunit of IL-9R that plays roles in IL-9-mediated allergy, inflammation, infection, and tumor immunity. While mammalian IL-9Rαs have been extensively investigated, avian IL-9Rα has not yet been identified and characterized. In this study, we cloned chicken IL-9Rα (chIL-9Rα) and performed a phylogenetic analysis, analyzed its tissue distribution, characterized the expression form of natural chIL-9Rα. Phylogenetic analysis showed that chIL-9Rα has less than 25% amino acid homology with mammalian IL-9Rαs. The chIL-9Rα mRNA was abundantly detected only in heart and mitogen-activated peripheral blood mononuclear cells. Furthermore, 4 monoclonal antibodies (mAbs) against chIL-9Rα were generated using prokaryotic recombinant chIL-9Rα (rchIL-9Rα). Using anti-chIL-9Rα mAbs, natural chIL-9Rα expressed on the splenocytes of chickens was observed by indirect immunofluorescence assay (IFA), and its molecular weight of 51 kDa was identified by Western blotting. Overall, our study reveals for the first time the presence of IL-9Rα in birds, and provides immunological tools for further investigating the roles of chIL-9 in diseases and immunity. [ABSTRACT FROM AUTHOR]

In the present work, the wettability of defective graphene oxide (GO) film is studied by molecular dynamics simulations. A water droplet is deposited on the surface of a graphene oxide membrane, and the contact angle is measured by fitting the liquid–vapor interface. Although pristine graphene has few hydrophobic properties with a contact angle of 95°, graphene oxide presents more hydrophilic properties, due to the stronger hydrogen bonds interactions at the interface. Moreover, the introduction of vacancy defects at the graphene oxide surface decreases the wettability of graphene oxide. We find that the contact angle of graphene oxide increases from 70° to 82°, with a defective concentration from 0% to 10%. Our results will help provide a new method for controlling the wetting properties of GO and its additional capabilities in device design for applications. [ABSTRACT FROM AUTHOR]