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Cases of human infection with a novel H7N9 avian influenza virus (AIV) were first reported in March 2013, which caused 115 deaths within a single year. Beyond that, other subtypes of H7 AIV were isolated from poultry in eastern China during the same period, including H7N7 and H7N2 AIV. In the present study, a subtype H3N2 AIV was isolated from ducks from Anhui Province, China. Sequence and phylogenetic analyses revealed that seven gene segments of this virus showed the highest sequence homology with that of the H7 subtype influenza virus, which is presumed to be the reassortants of the H3 and H7 subtypes AIV. The present study also reconfirmed that the reassortment between the H7 subtype and waterfowl-originating AIVs universally occurred in waterfowl. Animal inoculation tests showed that the virus has low pathogenicity in chickens; however, it could be replicated in the lungs of mice. The emergence of this H3N2 isolate emphasizes the importance of enhancing the surveillance of waterfowl-originating AIVs, the identification of novel reassortant strains, and characterization of their biological properties. [ABSTRACT FROM AUTHOR]

Purpose: The user churn (UC) of rural public digital cultural services (RPDCS) indicates that rural users no longer use RPDCS or have switched to other services. The purpose of this study is to investigate the factors influencing RPDCS's UC and to contribute toward bridging the rural digital divide. Design/methodology/approach: Based on the stimulus-organism-response theory, this study proposes a theoretical framework to investigate the factors influencing RPDCS's user churn. A total of 120 RPDCS users were initially recruited and 90 representative participants were chosen. Data were collected from the 90 respondents and 20 follow-up interviews. To examine the proposed framework and validate the correlations between these factors and UC, an analysis of variance (ANOVA) and multiple regression analysis were used. In addition, recommendations are made to avoid the UC of RPDCS to bridge the rural digital divide. Findings: The results indicate that the UC of RPDCS was stimulated by both physical and ability divides and RPDCS ineffectiveness, resulting in increased churn rates and an exacerbated digital divide. Thus, avoiding the UC of RPDCS is an important way to bridge the rural digital divide, which includes both the physical and ability divides. Originality/value: This study adds new knowledge about RPDCS and distinguishes it from previous research on public digital cultural services. In addition, the authors discuss how to avoid the UC of RPDCS, to bridge the rural digital divide. [ABSTRACT FROM AUTHOR]

During the service life of marine structures, environmental loads, such as earthquakes and ocean wave storms, may exert dynamic shear stresses of different amplitudes and orientations in the foundation soil. To investigate the undrained cyclic behavior of marine soft clay under a complex shear stress state, a laboratory study was performed on remolded clay specimens using a variable-direction dynamic cyclic simple shear system, through which two mutually perpendicular shear stresses can be simultaneously applied to the specimen within the horizontal x–y plane. Stress paths of linear, circular, and elliptical patterns were obtained by adjusting the amplitude ratio (η) between the two cyclic shear stresses and applied to investigate the undrained behavior of soft clay. The undrained cyclic responses of the clay specimens were presented and then analyzed from the viewpoint of energy dissipation. A strain-softening phenomenon was observed when the cyclic effective stress path reached the failure line determined by the monotonic test. The cyclic strength of clay subjected to multidirectional cyclic shear stresses (i.e., circular and elliptical stress paths) was 0.775η times that under unidirectional shear stress (i.e., linear stress path). The coupling effects of CSR and η on the cyclic strength and accumulation of residual pore water pressure can be uniformly correlated to energy dissipation. [ABSTRACT FROM AUTHOR]

Abstract: Novel kind of hybrid membrane was prepared by filling carbon graphite (CG) into poly (vinyl alcohol) (PVA) and chitosan (CS) blending mixture, in hopes of improving the separation performance of the membranes by the synergistic effect of blending and filling. The membranes were characterized through SEM, FTIR, XRD, DMA and PALS. The results showed homogenous distribution of graphite particles, considerable alteration of hydrogen bonding interaction, remarkable decrease of crystallinity degree, dramatic enhancement of mechanical properties and significant increase of free volume in CG-PVA/CS hybrid membranes. Sorption studies indicated that the degree of swelling of CG-PVA/CS hybrid membranes increased with graphite content increasing and the separation factor of benzene/cyclohexane was dominated by solubility selectivity rather than diffusivity selectivity. The concentration-averaged diffusion coefficients of benzene were larger than those of cyclohexane in all CG-PVA/CS hybrid membranes with different graphite loading. The pervaporation properties of CG-PVA/CS hybrid membranes for separation of benzene/cyclohexane mixtures were investigated through varying graphite content and mass ratio of PVA to chitosan in hybrid membranes. Higher permeation flux and separation factor of CG-PVA/CS hybrid membranes were desirably obtained, comparing to PVA and PVA/CS membranes. In particular, CG06-PVA60/CS40 membrane exhibited the highest separation factor of 59.8 with a permeation flux of 124.2g/(m2 h) at 323K, 1KPa. [Copyright &y& Elsevier]

The vacuum preloading method is commonly used to improve soft soils; however, it has rarely been studied from the perspective of energy consumption. The work done by the vacuum pump in the vacuum system can be consumed in various ways, including seepage consolidation of soil, water discharge along prefabricated vertical drains and horizontal drainage system (i.e. sand blanket or horizontal pipes), extraction of the air sealed in the drainage system and air leakage from the atmosphere. Equations governing these aspects of energy consumption were derived in this study. A theoretical model of the energy consumption of the vacuum preloading method was established and then solved to quantify the specific forms of energy consumption. Theoretical predictions and laboratory results demonstrate that the energy consumptions of seepage consolidation and water discharge are negligibly small compared with the total work by the vacuum pump, and most of the work done by the vacuum pump in the vacuum system is consumed during the extraction of leaked-in air. [ABSTRACT FROM AUTHOR]

Soil settlement is one of the most common and critical issues in geologic and geotechnical engineering. Due to various sources of uncertainties, it is hard to predict soil settlement accurately. An inverse analysis using the information provided by field measurements is desirable for prediction with higher confidence. In this study, an inverse framework based on ensemble Kalman filtering (EnKF) is proposed to evaluate the soil settlement with quantified uncertainty. The theoretical and practical effectiveness of this scheme is demonstrated through synthetic and realistic tests to predict soil settlement of embankment roads. Inferred results including quantified uncertainties are obtained based on Bayesian theory, which makes a distinction between this method and conventional settlement prediction methods. The results of two synthetic tests show the parameters inferred by the EnKF converge to true values, which verify the satisfactory performance of the proposed scheme. A realistic application of Saga airport road is investigated, and the simulated settlement results are consistent with the field measurements. Moreover, Sobol method is adopted to study the sensitivity of model parameters, and detailed parameter studies are conducted to estimate the influence of ensemble size, the value range of prior distribution and observation error. • An EnKF-based framework is proposed for settlement in a statistical and inverse way • The model parameters are updated based on sequentially observed data • Sobol method is used to study the sensitivity of model parameters • Improved predictions of subsequent settlement can be obtained [ABSTRACT FROM AUTHOR]

To improve the dewatering performances of the waste slurry, a new Fe-Polyacrylamide (Fe-PAM) flocculant was synthesized. Comparative analysis with various ionic forms of polyacrylamide (PAM) reveals that the Fe-PAM flocculant has the shortest flocculation time, the lowest optimal shear gradient for flocculation, and the best filtration performance. The capillary suction time (CST) of Fe-PAM treated slurry was improved from 262.3 s (raw sample) to 6.0 s. Moreover, sludge treated with Fe-PAM exhibits the lowest porosity under the same consolidation pressure and the highest permeability at the same void ratio. In addition, mercury intrusion porosimetry (MIP) results indicated that the Fe-PAM-treated sample features the highest number of largesized inter-aggregate pores (average value of 184.2 nm and median value of 23.2 nm) and the greatest pore connectivity (60.55 %), contributing to its superior permeability. The effectiveness of Fe-PAM is further elaborated through a synergistic flocculation mechanism, encompassing the electrical neutralization effect of the inorganic metal Fe3+ and the adsorption bridging effect of PAM's long-chains. This study demonstrates the potential of the synthesized Fe-PAM flocculant to enhance the dewatering efficiency of high-water content slurry and offers valuable insights for synthesizing advanced flocculants in slurry treatment engineering. • A novel organic-inorganic hybrid flocculant was synthesized. • Flocculant has the dual mechanism of electric neutralization and adsorption bridging. • The flocculation effect was compared with different ionic polyacrylamide. • Effectively reduce the bound water and accelerate the flocculation process. • The large pores in the soil samples after treatment increased significantly. [ABSTRACT FROM AUTHOR]

The clogging induced by particle transport is often mentioned in the practice of vacuum preloading, but the percolation behavior of soft clay under negative pressure is still not clear. To understand this, the percolation behavior was investigated using an artificial paste of silica sand and kaolinite under different hydraulic pressures. The hydraulic conductivity under positive pressure (90 kPa) was about twice as high as that of negative pressure (−90 kPa). However, the transport capacity and leached particle size under negative pressure were more significant than those under positive pressure, despite the same tendency of the porosity under the positive or negative pressure. This is an interesting and paradoxical finding, suggesting complexity accompanying the erosion and clogging under the nominal hydraulic gradient, where a higher concentration of the hydraulic gradient occurs under negative pressure. The percolation under negative pressure––a self-adaptive process––included three elements: (1) the colloidal transport of clay minerals; (2) colloid accumulation and clogging in the seepage channel close to the outlet; and (3) a gradient concentration close to the outlet. [ABSTRACT FROM AUTHOR]

The geotechnical tube technology has been widely used in the dewatering treatment of high-water-content slurries, such as engineering waste muds, mine water sludges, and dredging slurries. However, the existing engineering practice adopting the traditional geotextile tubes is characterized by low efficiency and difficult quality control. To address these issues, a new approach was developed by combining the geotextile tubes and vacuum preloading technology. In this method, several plastic drain boards were embedded in a geotextile tube as prefabricated horizontal drains (PHDs), and a vacuum was applied to promote drainage. The effectiveness of the proposed method was verified by a comparison test. A two-dimensional plane-strain analytical consolidation problem with a distributed drainage boundary was then formulated and solved to predict the consolidation process of soil in a vacuum preloaded geotextile tube. The analytical solution was validated against the results of a pilot field test, and then the influence of PHD spacing on the consolidation process was also discussed. Compared to the traditional geotextile tubes, the approach proposed in this paper promises good applicability and can effectively shorten the treatment time by 73.3% and reduce the water content of treated soils by 51.9%. [ABSTRACT FROM AUTHOR]

Canine health is consistently affected by the circulation of the H3N2 strain of canine influenza virus (CIV). Prior research has indicated that the isolation rate of H3N2 CIVs in dogs has gradually increased in China, and these viruses have progressively adapted to humans over the course of their evolution within canine hosts, posing a significant public health threat. However, the key factors influencing the spread of CIVs remain elusive. From January 2020 to December 2022, during the COVID-19 pandemic, strict epidemic prevention policies were implemented in China. Thus, this measure provides an ideal model for studying factors influencing the prevalence of CIVs. In this study, we continuously monitored the prevalence of CIVs in China before and after the COVID-19 pandemic. We found that the pathogen detection rate and seropositivity rate of domestic CIVs significantly declined after the implementation of epidemic control measures. However, after restrictions on human movement were lifted in 2023, the circulation of CIVs gradually increased. Our results demonstrate that restricting human activity directly impacts the epidemic caused by CIVs and provide a theoretical basis for the implementation of control measures during outbreaks of zoonotic diseases in human companion animals. [ABSTRACT FROM AUTHOR]

Vacuum preloading combined with prefabricated vertical drains is a widely used system for improving soft clay-dredged slurry deposits. However, the influence of the initial water content on clogging is not yet fully understood. In this study, laboratory model tests were conducted on slurry with initial water contents of 106%, 133%, and 159% during vacuum preloading. The process of vacuum preloading was monitored from the perspectives of discharged water volume, pore water pressure, as well as the displacement and strain profile of soil patches by using the novel particle image velocimetry (PIV) technique. The results showed that the clogging formation process could be divided into three stages based on the water discharge rate: rapid formation, transition, and slow formation. An increase in initial water content resulted in a larger horizontal displacement, leading to a thinner and denser clogging zone with lower permeability coefficients and a reduced rate of pore pressure dissipation. Empirical equations for the thickness of the clogging zone versus time were proposed using the PIV technique, providing a reference for theoretical consolidation calculations and making the calculations more practical by considering the variation of the clogging zone during vacuum preloading. [ABSTRACT FROM AUTHOR]

In this paper, a mechanical model of axial and circumferential bidirectional deformation has been developed by considering two factors: roller shape and radial reduction. Since the calibration of the roundness and that of the straightness of pipes are currently separate processes, the established mechanical models are based on a single direction. However, the established bidirectional mechanical model can describe not only the stress-strain distribution of the pipe in deformation to determine the position of the stress concentration but also the deformation curve of the pipe in different directions. As a result, it can serve as a theoretical basis for setting process parameters and optimizing roller shape. A large thin-walled pipe of Al6063 is modeled and then numerically simulated with FEM software of ABAQUS, and the results are compared with the model. Then, the process is fabricated and tested experimentally. The results are compared with the mechanical and numerical models. The distribution of equivalent stress and equivalent strain obtained by the model has a good match with the simulation results, and the maximum relative error is not more than 25%. The axial and circumferential deformation curve calculated by the mechanical model coincides well with the simulation and experimental results, and the maximum error is not greater than 3.0 mm. Obviously, both the experiment and the simulation have verified a superior validity of the model. [ABSTRACT FROM AUTHOR]