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In the steel-FRP composite bar (SFCB) reinforced concrete filled in an outer FRP tube, the bond behavior of SFCB in such FRP-confined concrete should differ from that in unconfined concrete. This paper aimed to understand the local bond behavior of SFCB in FRP-confined concrete. Sixty pullout specimens with variables (including the concrete strength, concrete cover-to-bar diameter ratio, and FRP confinement stiffness) were tested. The test results showed that the bond failure mode of SFCB was changed from concrete splitting in unconfined-concrete to pull-out in FRP-confined concrete. The study revealed that the development of FRP confinement promoted significant bond growth after concrete splitting and meaningful post-failure ductility. Greater FRP confinement stiffness resulted in the more pronounced the bond strength enhancement. In addition, a bond-confinement relationship at the bond interface was developed. Accordingly, the enhancement mechanism of SFCB in FRP-confined concrete is clarified: 1) FRP confinement substituted the cracked concrete in resisting to the wedge-action of SFCB; 2) FRP confinement improved the strength and deformability of interface concrete in resisting the shear-action of SFCB; 3) FRP confinement improved the friction. Finally, a bond strength model with a simple form was proposed, which can provide an accurate prediction of the bond strength of SFCB in FRP-confined concrete based on a confinement factor and the existing model in unconfined concrete. • The bond behavior of steel-FRP reinforced bar in FRP-confined concrete is studied. • The enhancement mechanism of FRP confinement on the bond is revealed. • The bond-confinement interaction at the bar-concrete interface is developed. • The bond strength model for SFCB in FRP-confined concrete is established. [ABSTRACT FROM AUTHOR]

In this paper, an experimental study is conducted to gain insight into the bond behavior of ribbed fiber-reinforced polymer (FRP) bar in FRP-confined concrete. Various parameters, including the ratio of concrete cover to bar diameter, concrete strength, and FRP confinement level, are considered in this study. The test results demonstrate the effectiveness of FRP confinement in changing the bond failure mode of FRP bar from the concrete splitting to the pullout and improving bond ductility and strength. The bond response of ribbed FRP bar in FRP-confined concrete is characterized by three distinct stages: uncracked stage, cracking enhancement stage, and cracking degradation stage. The bond mechanism within each stage is elucidated. The study reveals that the normalized bond strength is distinctly influenced by the ratio of concrete cover to diameter and FRP confinement level, while concrete strength exhibits a negligible impact. Finally, the study proposes a novel model for predicting the bond strength of the ribbed FRP bar embedded in both unconfined and FRP-confined concrete. • The bond behavior of ribbed FRP bar in FRP-confined concrete is studied. • The bond mechanism of ribbed FRP bar in FRP-confined concrete is elucidated. • The bond strength model for FRP bar in both unconfined and FRP-confined concrete is developed. [ABSTRACT FROM AUTHOR]

Evaporation power generation (EPG), hailed as a promising clean power generation technology, has garnered significant attention. Nonetheless, achieving consistent and replicable performance of EPG remains a major challenge, hampering its practical application potential. Herein, we present the design of a tri-layered poly-ionic membrane (TL-PIM) inspired by transpiration processes in plants, that can not only continuously output electricity with an average voltage of ∼0.6 V for over 8 consecutive days with a maximum power density of 1.6 µW cm−2, but can also be reused for at least 70 cycles (> 350 h) with a stable voltage, demonstrating superior repeatability over most previous works. The excellent long-lasting and repeatable performance of EPG in the TL-PIM can be attributed to the stable nanochannels constructed by a hydrophilic polymer, 2D nanosheets, and poly-ionic liquids (PILs), where the bromide ions (Br-) in the PILs can shuttle back and forth selectively and efficiently during the power generation and discharge processes. More importantly, the TL-PIM can be integrated linearly to generate electricity within a wide range of temperatures and humidity, even outdoors, showcasing remarkable environmental adaptability. These findings on EPG indicate that the bio-inspired TL-PIM offers a promising venue for continuous and reproducible electricity generation by harnessing thermal energy from moisture, which holds significance for the sustainable utilization of EPG as a renewable energy source in the future. [Display omitted] • A novel three-layer multi-ion membrane inspired by the plant transpiration process is prepared. • Stable nanochannels lead to long-lasting and repeatable evaporation power performance. • The evaporation power generation can continuously supply electricity with 0.6 V for 180 h. [ABSTRACT FROM AUTHOR]

• Long-term aging test of CFRP laminates subjected to different solutions are made. • Effects of specimen thickness on aging test of CFRP laminates are discussed. • New analytical models of accelerated factors are proposed. • The proposed models are applied to predict long-term properties of CFRP laminates. In this paper, an experimental research was undertaken to investigate the effect of specimen thicknesses on water absorptions and flexural strengths of wet lay-up CFRP laminates subjected to distilled water or alkaline solution immersion up to 180 days. Test results showed that the water uptake and flexural strength retention of CFRP laminates were significantly affected by the adopted specimen thickness. For the same aging time, the water uptake of CFRP laminates decreased in the early stage of immersion and increased in the later stage of immersion with the increase of specimen thickness. Meanwhile, the flexural strength retention generally increased as specimen thickness increased. In addition, a new thickness-based accelerated method for hygrothermal aging test of CFRP laminates was proposed. The accelerated factors of the water uptake and flexural strength retention of CFRP laminates were theoretically deduced. The proposed analytical model of accelerated factors was verified with current test data, and then applied to predict long-term properties of CFRP laminates. Compared with the traditional temperature-based accelerated method, the new thickness-based accelerated method is much easier to apply to predict long-term properties of CFRP laminates with good accuracy. [ABSTRACT FROM AUTHOR]

Highlights • Embedding CNFs/epoxy sensors into concrete components is studied at first time. • The piezoresistive performances of the CNFs/epoxy sensors are evaluated. • A compensation circuit is proposed to eliminate the effect of temperature. • The calibration and monitoring curves exhibited a consistent variation trend. Abstract In this study, embedded strain sensors based on the principle of piezoresistivity were fabricated by epoxy-based composites filled with different contents of carbon nanofibers (CNFs). The piezoresistive performances and relevant parameters including gauge factor, linearity, repeatability and hysteresis of these sensors were investigated. A compensation circuit was proposed to eliminate the influence of temperature on sensing signals of the sensors. The CNFs/epoxy sensors were embedded into concrete cylinders to monitor their compressive strains under monotonic and cyclic loadings, thereby assessing practical applications of the CNFs/epoxy sensors as strain sensors for monitoring concrete structures. The results indicate that the sensors containing 0.58 vol% of CNFs, which have a gauge factor of 37.1, a linearity of 5.5%, a repeatability of 3.8% and a hysteresis of 6.3%, exhibited better piezoresistive performance compared to those containing 0.29 vol% of CNFs. The calibration and monitoring curves exhibited a consistent variation trend when the cylinders embedded with sensors were subjected to monotonic and cyclic loadings. This demonstrates that the CNFs/epoxy sensors have considerable potential to be used as embedded strain sensors for structural health monitoring of concrete structures. [ABSTRACT FROM AUTHOR]

Highlights • Thickness-based accelerated aging test method (ThAM) is firstly proposed for resin materials. • Acceleration factors are theoretically deduced for water absorption and tensile behaviours of resin materials. • Effects of specimen thickness on water absorption and tensile strength retention of resin materials are studied. • The proposed ThAM ensures stable accelerated efficiency without changing the degradation mechanism of resin materials. Abstract This paper proposes a novel accelerated test method based on the thickness of resin materials. This method is to overcome the adverse influence of high temperature on the reliability of experimental results of the accelerated tests widely adopted in the current practice. To verify the proposed thickness-based accelerated method (ThAM), an experimental investigation was conducted focusing on the water absorption and tensile properties of epoxy resin. The results suggest that the existing temperature-based accelerated method (TAM) cannot be applied when the test temperature is high as in this case the degradation mechanism of materials is probably changed. The acceleration factor of TAM is greatly dependent on the type of test solution, which further limits the application in the accelerated test. Compared with TAM, the new method is much easier to apply, and more stable and reasonable to accelerate the aging test of epoxy resin. [ABSTRACT FROM AUTHOR]

In this paper, carbon nanofibers (CNFs) with high aspect ratio were dispersed into epoxy matrix via mechanical stirring and ultrasonic treatment to fabricate self-sensing CNFs/epoxy composites. The mechanical, electrical and piezoresistive properties of the nanocomposites filled with different contents of CNFs were investigated. Based on the tunneling conduction and percolation conduction theories, the mechanisms of piezoresistive property of the nanocomposites were also explored. The experimental results show that adding CNFs can effectively enhance the compressive strengths and elastic moduli of the composites. The percolation threshold of the CNFs/epoxy composites is 0.186 vol% according to the modified General Effective Media Equation. Moreover, the stable and sensitive piezoresistive response of CNFs/epoxy composites was observed under monotonic and cyclic loadings. It can be demonstrated that adding CNFs into epoxy-based composites provides an innovative means of self-sensing, and the high sensitivity and stable piezoresistivity endow the CNFs/epoxy composites with considerable potentials as efficient compressive strain sensors for structural health monitoring of civil infrastructures. [ABSTRACT FROM AUTHOR]

Uniaxial compressive tests (UCS) were carried out to investigate the influence of pre-existing fissure geometry parameters (various dip angles, lengths, widths, and numbers) on the mechanical properties and deformation failure modes of low-strength rock samples. The results suggested that UCS, elastic modulus and axial peak strain were reduced by pre-existing fissures, but the reduction degree was strongly associated with the pre-existing fissure geometry. In addition, the UCS and elastic modulus of the low-strength rock samples were very sensitive to fissure dip angle and number, while the fissure number had the greatest effect on both of them. The axial peak strain was mainly influenced by the fissure dip angle. Moreover, due to the influence by the pre-existing fissures, the stress-strain curves of low-strength rock specimens usually changed from rapid drop to multistage decline, and even to horizontal extension slow decline. This indicated that low-strength specimens usually can change from brittle failure to ductile failure, and even had ductile flow deformation damage occurring under the influence of the pre-existing fissures. This change did not occur in high-strength rock mass. The fracture morphology of low-strength rock specimens was primarily affected by the fissure dip angle, and the influence of the fissure number on the fracture morphology was constrained by the fissure dip conditions, while the fissure length and width had fairly little effects on the fracture morphology of low-strength rock samples. This paper may provide new insights into the principle features of rock failure under uniaxial compression for future studies. [ABSTRACT FROM AUTHOR]

Indium-tin-oxide (ITO) thin film resistance temperature detectors (RTD) were fabricated on alumina substrates by RF sputtering in this study. The scanning electron microscope (SEM) and atomic force microscope (AFM) images show that the thin films deposited under argon and oxygen were more smooth and dense than those deposited without oxygen. The film became more stoichiometric when no more than 20sccm oxygen was introduced. The XRD result shows that ITO deposited under argon and oxygen had an In 2 O 3 crystal structure with a preferred orientation of (222) and the film deposited without oxygen showed a preferred orientation of (400). High temperature tests revealed that the resistance changed linearly with the temperature and the RTD had different temperature coefficient of resistance (TCR) in different temperature ranges. The absolute value of TCR was large and the RTDs showed promising application at high temperature, especially from 600 °C to 900 °C. [ABSTRACT FROM AUTHOR]

• Cyclically loaded elliptical concrete confined by FRP (FCC) is investigated. • Mechanism of non-uniform hoop strain distribution is clarified. • Cyclic behavioral characteristics of elliptical FCC are properly modeled. The previous studies on elliptical concrete confined with fiber-reinforced polymer (FRP) are mainly concerned with their monotonic compressive responses. By contrast, no research has been focused on their performance under cyclic axial loading. Motivated by this research gap, the behavioral characteristics of cyclically compressed elliptical FRP-confined concrete (FCC) were investigated in this research. The experimental parameters included the aspect ratio varying between 1.0 (circular section), 1.3, 1.7 and 2.0, the number of FRP layers, and the loading pattern (monotonic loading or two schemes of cyclic loading). The results revealed that plastic strains and stress degradation in elliptical FCC were confinement-independent parameters, regardless of confinement efficiency (affected by sectional geometry) and confinement level (governed by FRP thickness). This was similar to the case of cyclically loaded rectangular FCC (characterized by depth-to-width ratio). Moreover, the mechanism of non-uniform hoop strain distribution was dominated by two aspects, namely curvature radius-induced varying confinement stiffness and concrete cracking-induced strain localization. In contrast, the cyclic loading had a marginal effect on this distribution. Based on the monotonic model (considered as envelope curve) for elliptical FCC and the hysteretic rules originally for circular FCC, the complete compressive behavior of cyclically loaded elliptical FCC could be modeled with favorable accuracy. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer (FRP)-steel tubed reinforced concrete (FSTRC) columns present promising engineering applications due to the reasonable integration of three constituent materials. Compared with the numerous studies on their performance under monotonic loading, relatively few studies have focused on their cyclic axial behavior. Moreover, the available models for plain concrete solely confined by FRP might be incapable of estimating the confined concrete behavior in cyclically loaded FSTRC due to the possible effect induced by the steel reinforcement in concrete, the additional steel tube confinement, and the girth gaps at column ends. To this end, this paper investigated circular FSTRC stub columns under monotonic and cyclic axial loading. The test results confirmed that the inclusion of reinforcement had noticeable effects on the unloading path since the tensile axial stresses in longitudinal steel bars slowed down the stiffness degradation of the inner concrete during unloading. For envelope cycles, the increase of the additional steel confinement level had a negligible impact on the plastic strain and the stress deterioration of the inner concrete. A confinement model was developed to estimate the full-range behavior of the FRP-steel dually confined reinforced concrete under cyclic axial loading with favorable accuracy. [ABSTRACT FROM AUTHOR]

• MD simulations of electrokinetic nanoconfined ionic liquids flow were performed. • The perpendicular configuration of cation at the silica surface was identified. • Modulating mechanism of external stimuli on electrokinetic flow of ionic liquids. • Developed quantitative relation between streaming current and external stimuli. The electrokinetic flow of ionic liquids (ILs) is widely used in electrochemical engineering applications. Herein, flow behavior and controlling mechanism of ILs driven by electrical field were investigated via molecular dynamics simulations. During the flow process, the cations prefer to allocate at the interface in a perpendicular configuration, while the anions tend to distribute randomly. In the interface region, the perpendicular cations and accumulated ILs would significantly enhance the local viscosity of ILs, which dominates the velocity distribution and total flux of the electrokinetic flow of confined ILs. Compared with the pressure and surface charging density, the nanochannel size would induce a larger impact on the average velocity, total flux, and streaming current of the electrokinetic flow of confined ILs. These quantitative results on the electrokinetic flow are crucial for the rational design of ILs-based devices or other chemical engineering processes. [ABSTRACT FROM AUTHOR]

Three new compounds, butyl homononactate ( 5 ), butyl nonactate ( 6 ), 8-actyl homononactic acid ( 7 ), along with four known compounds homononactic acids ( 1 ), nonactic acid ( 2 ), homononactyl nonactate ( 3 ), homononactyl homononactate ( 4 ) were isolated from the marine Streptomyces griseus RSH0407, derived from the plant Salicornia sp., Chenopodiaceae. Their structures were elucidated by extensive spectroscopic techniques and by comparison with data reported in the literature. The absolute configuration of 3 was first reported by using X-ray copper radiation. Compound 5 exhibited cytotoxic activities against the HCT-8, A2780, BGC-823, BEL-7402, and A549 cell lines in vitro , with IC 50 values of 2.87 ± 0.20, 4.90 ± 0.30, 2.19 ± 0.32, 5.07 ± 0.23 and 1.78 ± 0.18 μM, respectively, and compounds 4 – 7 showed weak antibacterial activities against four bacterials respectively. [ABSTRACT FROM AUTHOR]

The strain and damage self-sensing properties of carbon nanofibers (CNFs)/flax fiber-reinforced polymer (FFRP) laminates under tension were investigated via simultaneously measuring the changes of electrical resistance (ER) and acoustic emission (AE) signals. The piezoresistive mechanisms together with the damage evolution of CNFs/FFRP laminates were also explored. The results revealed that both ER and AE responses to tensile strains in CNFs/FFRP laminates could be segmented into three stages, which confirmed their good damage self-sensing ability. The isochronous and reversible electrical resistance responses to tensile strains proved the stability and repeatability of strain self-sensing capability for CNFs/FFRP laminates. Moreover, in-situ ER measurement is sensitive not only to new damages but also to existing damages, whereas AE signals are only sensitive to new damages. Therefore, adding a small amount of conductive CNFs into non-conductive FFRP laminates could provide an effective strategy to achieve the self-sensing ability in their strain and damage development. [ABSTRACT FROM AUTHOR]

• Rectangular FRP-concrete-steel double-skin tubular columns (DSTCs) are tested. • Four parameters are considered to study the axial compressive behavior of DSTCs. • The axial stress-strain curves of confined concrete are approximately trilinear. • Increasing aspect ratio has positive effect on the behavior of confined concrete. • A design-oriented three-stage stress-strain model of rectangular DSTCs is proposed. This paper presents the experimental results of monotonic axial compression tests on eighteen glass fiber-reinforced polymer (FRP)-concrete-steel double-skin tubular stub columns (DSTCs) with a rectangular outer glass FRP tube and an elliptical/rectangular inner steel tube, as well as eight rectangular glass FRP-confined hollow stub columns (FCHCs) with an elliptical inner void. The effects of cross-sectional aspect ratio, FRP thickness, void area ratio and the shape of inner steel tube (i.e., elliptical and rectangular) on the axial compressive behavior of confined concrete core in rectangular DSTCs are considered and analyzed. The test results demonstrate that rectangular DSTCs possess excellent bearing capacity and ductility. Additionally, the axial stress-strain curves of confined concrete core in rectangular DSTCs are approximately trilinear and show obvious post-peak softening phenomenon because of the non-uniform and insufficient confinement. Furthermore, the larger aspect ratio, the thicker FRP tube, the higher void area ratio, as well as elliptical inner steel tube (compared with rectangular) have positive confinement effect on the axial compressive behavior of confined concrete core in rectangular DSTCs. Based on the analysis of experimental data, a design-oriented three-stage stress-strain model (considering post-peak softening behavior) of confined concrete in rectangular DSTCs with elliptical inner steel tube is proposed. Through the comparison, it is found that the predictions calculated by the proposed model accord well with the experimental results. [ABSTRACT FROM AUTHOR]

Background: Presacral venous bleeding during rectal mobilization is uncommon but potentially life-threatening. Various methods have been proposed for controlling the bleeding, but each has some obvious limitations in clinical practice. We report a simple technique that was designated as circular suture ligation. This technique was efficient in controlling presacral venous bleeding encountered during rectal mobilization.Methods: The key point of circular suture ligation was to control the bleeding by suture ligating the venous plexus in one or more circles in the area with intact presacral fascia that surrounds the bleeding site while the bleeding site was temporarily controlled with fingertip pressure. From September 2007 to December 2011, 258 patients underwent rectal surgery in our department because of rectal cancer. Uncontrolled presacral venous bleeding with traditional methods was encountered in eight patients (3 %) with estimated blood loss from 300 to 5,000 ml.Results: Bleeding was successfully controlled in all eight patients with the circular suture ligation. None of the patients required reoperation for bleeding or other issues. No patients developed chronic pelvic pain after the operation.Conclusions: Our experience suggests that circular suture ligation of venous plexus in the area with intact presacral fascia that surrounds the bleeding site is an effective and simple technique to control presacral venous bleeding when traditional techniques fail. [ABSTRACT FROM AUTHOR]

Abstract: Ninety pullout specimens were used to study the bond behavior of glass fiber reinforced polymer (GFRP) ribbed rebars with thirty different specially designed rib geometries to the normal strength concrete. The test variables were the rebar diameter, rib spacing, and rib height. For each specimen, the bond failure mode, the average bond strength, the slip at the loaded end, the initial bond stiffness, and the bond–slip relationship curves were analyzed. It was found that the bond strength and bond–slip performance of these specially machined rebars varied with the combinations of rib spacing and rib height, alternatively known as the relative rib area(ratio of projected rib area normal to bar axis to product of nominal bar perimeter and center-to-center rib spacing). Based on analysis of the test results, design recommendations involving optimal rib spacing and rib height were made concerning optimum rib geometries of GFRP ribbed rebars with superior bond–slip performance. [Copyright &y& Elsevier]

Abstract: Due to significant advantages over GFRP rebars, namely high tensile strength, high elastic modulus, and good ductile properties, GFRP/steel wire composite rebars offer a superior alternative to ordinary steel rebars. However, experimental researches on this new type of rebar have been limited, especially those on the bond performance. This research is designed to investigate the bond behavior between GFRP/steel wire composite rebars and concrete. According to American Concrete Institute (ACI) code, a total of 180 pull-out specimens were tested under monotonic static loading conditions. The test parameters were the rebar rib spacing, rebar diameter, embedded length, concrete compressive strength, concrete cover thickness, and concrete cast depth. Based on the numerical analysis of the test results, new criteria for acceptable bond performance of GFRP/steel wire composite rebars to concrete were developed. Designed recommendations for the modification factor of concrete cover thickness, the modification factor of concrete cast depth, and the critical value of bond slip at both free and loaded ends were derived. The calculation formula of bond strength and the basic development length were proposed, and the calculation principle of development length of concrete structures reinforced with GFRP/steel wire composite rebars was suggested. [Copyright &y& Elsevier]

• Elliptical FRP-confined high-strength concrete stub columns are axially loaded. • Increasing aspect ratio always has adverse effect on behavior of inner concrete. • Typical stress–strain curves of confined concrete are categorized into four types. • Threshold for sufficient confinement of elliptical FRP-confined concrete is given. • A design-oriented model for elliptical FRP-confined concrete is developed. Elliptical fiber-reinforced polymer (FRP)-confined concrete members have gained increasing attention due to their aesthetical characteristics and structural efficiency. This paper investigated the behavior of 24 elliptical FRP-confined concrete stub columns under axial compression. Effects of the amount of FRP confinement, the cross-sectional aspect ratio, and the use of high-strength concrete were discussed. The test results indicated that the stress and strain capacities of the confined concrete were enhanced with the increasing amount of FRP confinement. By contrast, the increasing sectional aspect ratio and the use of high-strength concrete had an adverse effect on the inner concrete's axial behavior due to the increasingly non-uniform distribution of FRP confining pressure. In general, the typical stress–strain curves of elliptical FRP-confined concrete were categorized into four types. Furthermore, using the concept of equivalent diameter, the threshold for sufficient confinement of elliptical FRP-confined concrete was determined by the equivalent confinement stiffness ratio to ensure an overall ascending behavior. After addressing some key issues, a design-oriented model for elliptical FRP-confined concrete with a relatively wider range of concrete strength (from 32.6 to 72.4 MPa) was developed herein with more satisfactory accuracy than existing models. This model with a simple form could be naturally reduced to a widely accepted model for FRP-confined concrete with circular sections. [ABSTRACT FROM AUTHOR]

• Bond durability of GFRP bars in concrete under immersion and load was investigated. • Degradation mechanism of GFRP bars in concrete was clarified. • Sustained load could accelerate the degradation of the bond performance. • Bond strength after 50 years was predicted according to fib Bulletin 40. In this paper, the bond durability of glass fiber-reinforced polymer (GFRP) bars in seawater sea-sand concrete (SWSSC) under the coupling effect of seawater immersion and sustained load was experimentally investigated. The test parameters included bar diameter (12 and 16 mm), immersion time (90, 180, and 270 days), and sustained load condition (loaded and unloaded). Test results showed that for the specimens with a small bar diameter, the bond strength had a slight growth at the initial stage of exposure mainly due to the water swelling of the bar, and then decreased due to the bond degradation. For the specimens with a large bar diameter, the bond strength increased with the increase of immersion time, which was determined by the increasing compressive strength of SWSSC. The sustained load reduced the bond strength of the specimens with a small bar diameter due to its acceleration of bond degradation, but had little effect on the bond strength of the specimens with a large bar diameter. The degradation mechanism was the rib deterioration of the bars caused by seawater immersion. Moreover, the sustained load could accelerate the degradation. The predicted bond strength retention of the specimen with a bar diameter of 12 mm under the coupling effect of the marine environment (moisture saturated and the mean annual temperature of 25–35 °C) and sustained load is 52% after 50 years of service. [ABSTRACT FROM AUTHOR]

• CNN models for predicting creep and shrinkage of concrete are researched. • The constitutive law of concrete based on the proposed CNN models is presented. • An ABAQUS user subroutine of concrete creep and shrinkage is developed. • The performance of CNN models is better than the B4 model. • Developed user subroutine predicts well the long-term deformation of a RC beam. The problem of long-term deformation caused by creep and shrinkage (C&S) needs to be concerned in the design and service of concrete structures. Although various models have been developed to predict the C&S of concrete, more accurate and reliable prediction methods are still needed. The models of C&S based on convolutional neural networks (CNNs) are proposed in the study. The performance of the CNN models is verified by using 906 sets of creep experiment data and 1114 sets of shrinkage experiment data in the Northwestern University (NU) database. Besides, the K-means clustering algorithm is introduced to divide the data set into the training set, validation set, and test set, and the problem of uneven distribution of the data set on the time scale is overcome. Finally, the incremental viscoelastic constitutive law of concrete based on the developed CNN models is proposed, and the ABAQUS user subroutine for simulating C&S of concrete is developed. The availability of the user subroutine is validated by the creep and shrinkage test of a reinforced concrete beam. The research can provide reliable methods for the rapid prediction of C&S of concrete and the simulation analysis of long-term deformation of concrete structures. [ABSTRACT FROM AUTHOR]

• Vascular abnormality at inflamed sites facilitates efficient accumulation of red blood cell vesicle (ReV). • Lipids of ReV optimizes cerium oxide crystallization process, leading to smaller size and higher Ce(III) content. • The resulted Ce-ReV shows superior therapeutic outcomes over clinically used drugs in murine colitis model. • Hybridization with mesenchymal stem cell exosomes exerts additional repair benefit for improving the therapeutic outcomes. [Display omitted] Reactive oxygen species (ROS) are key contributors to inflammatory progression and damage. Upon clinical and experimental observation of vascular abnormalities in acute inflammatory diseases, we explore cellular vesicles as templates and carriers to elevate therapeutic performance of nano-antioxidant. Specifically, we develop a mild one-pot approach for in situ growth of cerium oxide (Ce) nanocrystals onto nano-sized red blood cells vesicles (ReVs). Besides excellent biocompatibility, Ce-ReVs have very high ROS-scavenging activity, which is experimentally and theoretically explained by discovering the unique functions of membrane lipids in optimizing Ce nanocrystals with ultrasmall size (~ 3 nm) and ultrahigh Ce(III) content (~ 60.8%). In colitis and acute liver injury models, Ce-ReVs notably enhance accumulation at the inflamed sites and confer strong ROS elimination. Moreover, we upgrade the system by hybridizing ReVs with mesenchymal stem cell-derived exosomes and demonstrate additional repair function of highly damaged tissues, further verifying the satisfactory flexibility and therapeutic efficacy. [ABSTRACT FROM AUTHOR]