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• Shear behavior of RC beams strengthened with U-wrapping PET FRP was studied. • Effects of shear span ratio on shear performance of U-wrapping PET FRP-strengthened RC beams were investigated. • Seven design models of FRP shear contribution were evaluated and a modified model was proposed. • An FE model incorporating the bond-slip relationship between FRP and concrete was developed. This paper reports the investigations of experimental and numerical programs on the shear performance of U-shaped Polyethylene Terephthalate (PET) FRP-retrofitted RC beams. Twelve RC beams were fabricated and tested under monotonic three-point loading with the test parameters being FRP strip width and shear span-to-effective depth ratio. A comprehensive analysis and investigation were conducted in terms of the failure modes, shear load–deflection responses, shear capacities, the strain evolution of FRP and stirrups, and the interaction of shear contributions among FRP, stirrups and concrete. Larger debonding strains were observed for PET FRP. Five design guidelines and two models available in the literature were assessed against the measured PET FRP shear contribution. A modified model of the shear contribution for PET FRP was developed and verified by the test results. Finally, a finite element model was established to further understand the shear performance of retrofitted beams, in which the bond-slip relationship between concrete and FRP was considered. The FE model was validated by comparing the test and FE results. The proposed FE model could accurately capture the propagation of shear critical cracks and FRP debonding failure for the specimens with medium and large shear spans. [ABSTRACT FROM AUTHOR]

An experimental work on the shear strengthening of reinforced concrete (RC) beams completely wrapped by large rupture strain (LRS) FRP is presented in this paper. A total of 14 three-point bending tests were carried out on simply supported RC beams, with a focus on the impacts of the shear span-to-depth ratio (1.53, 2.25, and 3.01) and FRP reinforcement ratio (0.37 %, 0.75 %, and 1.12 %) on the shear behavior of RC beams strengthened with LRS FRP. For the beams with a median length, the ductility coefficients increased by 81 %, 154 %, and 335 % with the increase in FRP reinforcement ratio. For the long beams, the ductility coefficients increased by 116 %, 286 %, and 470 % as the FRP reinforcement ratio improved. The ductility markedly improved with the increase in shear span-to-depth ratio. PET FRP's fracture was not found at the ultimate state, and the improvement in mid-span deflection after the peak state was mainly contributed by the shear deformation. The strengthened specimens exhibited a ductile shear failure mode. For the short RC beams, the shear capacity was slightly enhanced, and the ductility was not improved after being strengthened. The strengthened short RC beams still showed a brittle diagonal compression failure mode. The experimental shear contribution of PETT FRP was compared with the prediction of the existing design guidelines. Finally, an effective strain model of PET FRP, including the shear span-to-depth ratio effect, was proposed and verified with the experimental results. • Shear performance was studied for shear-critical RC beams completely wrapped by LRS FRP. • Ducile shear failure of LRS FRP-strengthened RC beams was observed. • Effect of shear span to depth ratio on shear behavior was discussed. • Six design guidelines for FRP shear contribution were evaluated. [ABSTRACT FROM AUTHOR]

• The seismic behaviour of LRS FRP-strengthened shear critical columns was experimentally investigated. • The advantage of LRS FRP-strengthened RC columns in seismic retrofit was demonstrated. • Progressive failure and superior ductility were observed for shear critical columns strengthened with LRS FRP. • An axial-shear-flexure approach was developed to predict the envelope curves of LRS FRP-strengthened columns. This paper presents an experimental study on the seismic behaviour of shear critical square columns strengthened by large rupture strain (LRS) FRP under reversed cyclic lateral load together with constant axial load. The experimental program included 2 control columns, 6 LRS FRP-strengthened columns, and 2 CFRP-strengthened columns. The tested specimens' failure modes, hysteretic responses, ductility, and cumulative energy dissipation were carefully analyzed. The influences of axial load ratio, FRP layers, and FRP type on the seismic performance of these columns were investigated. Compared with the control column, the ductility ratio and energy dissipation of the column wrapped by 3-layer LRS FRP at a low axial load ratio were raised by 491.7 % and 6498.3 %, respectively. The advantage of LRS FRP over CFRP in seismic retrofitting for shear critical RC columns was demonstrated through comparative analysis for the first time. Although the tensile stiffness of 1-layer PET FRP is much smaller than 1-layer CFRP, the ductility ratio and cumulative energy dissipation of the 1-layer PET FRP-strengthened column under a low axial load ratio were still slightly larger than that of the column wrapped by 1-layer CFRP. The CFRP-strengthened column under a high axial load ratio showed sudden explosive failure, while the LRS FRP-strengthened columns exhibited progressive failure. In addition, the axial flexure shear interaction (ASFI) method considering buckling of longitudinal reinforcement in FRP-confined concrete was developed and verified by comparing test results and predicted envelope curves. [ABSTRACT FROM AUTHOR]

• Presenting the first-ever experimental study of PEN FRP-MTCCs. • Illustrating its excellent structural performance, especially in terms of ductility. • Evaluating the performance of the newly developed prediction method. • Demonstrating an environmentally friendly solution for coastal infrastructure. Fiber-reinforced polymer (FRP)-concrete-steel hybrid multi-tube concrete column (MTCC) is a new type of composite column and comprises a number of steel inner tubes, an FRP external tube and concrete fillings for the space inside all the tubes. This paper presents a series of experimental tests on four large-size square PEN (polyethylene naphthalate) FRP-MTCCs, of which the PEN fibers were extracted from recycled plastic bottles. The parameters of interest include the FRP thickness and the steel tube configuration. The experimental results showed that the large-size square MTCCs with PEN FRP exhibited excellent ductility due to the effective confinement provided by PEN FRP jacket and steel tubes. A prediction method for the square PEN FRP-MTCCs has been developed in the present study to consider the unique characteristics of the column and is able to produce reasonable predictions for the experimental results. This study serves to present an innovative alternative in an environmentally friendly way that can replace the conventional bridge piers in coastal and salina regions. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive experimental and theoretical work was conducted on the bending performance of hybrid carbon-polyethylene terephthalate (C-PET) fiber-reinforced polymer (FRP) strengthened reinforced concrete (RC) beams with U-strip anchorages. Eleven RC beams were tested under a four-point bending load to investigate the influence of stacking sequence and U-strip anchorages. The bending performance of strengthened beams was carefully examined and discussed with regard to failure mode, flexural strength, ductility coefficient, and FRP strain development. The hybrid strengthened beams with U-strip anchorages exhibited 10.54 %−21.97 % higher flexural strength and 4.30 %−206.27 % higher ductility factors than the corresponding strengthened beams without U-strip anchorages. In addition, a theoretical analysis model with high accuracy was proposed to simulate the load-deflection curves of the strengthened beams based on the section analysis and plastic hinge model. Finally, this paper evaluated the accuracy of design guidelines (including GB 50608, ACI 440.2 R, and CNR DT 200 R1) in calculating the load-bearing capacities of strengthened beams. • Flexural performance was studied for hybrid carbon-PET FRP-strengthened RC beams with U-strip anchorages. • Effect of U-strip anchorages on flexure performance was investigated and discussed. • A simple but accurate theoretical model for load-deflection curves was proposed. • The design guidelines were evaluated in calculating the load-bearing capacities of the strengthened beams. [ABSTRACT FROM AUTHOR]

This paper experimentally investigated the monotonic and cyclic compressive behavior of concrete confined with hybrid carbon fiber-reinforced polymer (CFRP) and large rupture strain (LRS) FRP. A total of 34 concrete cylinders wrapped by FRP were prepared and tested under monotonic/cyclic axial compression. The effects of FRP types and thickness on the failure mode, efficiency factor, hybrid effect, stress-strain response, and energy dissipation were carefully investigated. Test results verified that the hybrid confinement mechanism can fully utilize the advantages of both types of FRP and avoid their essential shortcomings. LRS FRP effectively improved the utilization of CFRP and increased the deformation and energy dissipation capacity of concrete. Hybrid inner CFRP and outer LRS FRP serve as a confinement device that can achieve a progressive failure mechanism for concrete. In addition, an analysis-oriented model was developed and constructed to simulate the monotonic stress-strain behavior of hybrid-wrapped concrete. This analysis-oriented model focuses on the lateral stress-strain relationship and the localized CFRP fracture effect. Finally, a cyclic stress-strain model of hybrid-wrapped concrete was developed using the analysis-oriented model as an envelope model. The proposed model can accurately capture monotonic/cyclic stress-strain behaviors. • The compressive behavior of hybrid-wrapped concrete was carefully investigated. • Progressive failure and superior ductility were observed for hybrid-wrapped concrete. • An analysis-oriented model was developed considering the localized CFRP fracture effect. • The accuracy of compression model of hybrid FRP-wrapped concrete was verified. [ABSTRACT FROM AUTHOR]

• A complexing strategy of polycrystalline and single crystal NCM was proposed to optimize the comprehensive performances of high-rate Li-ion batteries. • The capacity fading of polycrystalline NCM was demonstrated mainly due to the structural collapse and severe electrode/electrolyte interface parasitic reactions. • The capacity fading of single crystal NCM mainly arose from the sever heat accumulation and the accelerated parasitic reactions with electrolyte under high temperature. • Excellent high-temperature storage and cycling stability of prototype high-rate Li-ion batteries were achieved through dedicate manipulation of the cathode materials. Lithium Nickel Manganese Cobalt Oxide (NCM) is extensively employed as promising cathode material due to its high-power rating and energy density. However, there is a long-standing vacillation between conventional polycrystalline and single-crystal cathodes due to their differential performances in high-rate capability and cycling stability. Herein, a complexing strategy is proposed based on the investigation of capacity fading mechanism of both polycrystalline and single crystal NCM. A series of mixed cathodes containing both types of NCM particles with different mass ratio have been compared. The optimized NCM-37 cathode realized a balance between high-rate performances, high-temperature storage, and stable cycling. Specifically, the NCM-37 sustains a capacity retention of 98.4% after 300 cycles under 1 C charge/30 C discharge. Moreover, after storage at 60°C for 7 days, the capacity retention and recovery ratio are 91.73% and 95.02%, respectively. This work demonstrates an efficient approach to improve the comprehensive performances of prototype lithium-ion batteries by cathode manipulation, which can fully utilize the advantages and suppress the disadvantages of conventional polycrystalline and single crystal NCM particles. [Display omitted] [ABSTRACT FROM AUTHOR]

• The seismic behaviour of LRS FRP-wrapped non-ductile RC columns was experimentally investigated. • The advantage of LRS FRP-wrapped RC columns in seismic retrofit was demonstrated. • The influence of FRP confinement stiffness on seismic performance was studied. • The accuracy of cyclic compression model model of LRS FRP-strengthened concrete was verified. This paper presents experimental studies and numerical simulations of circular reinforced concrete (RC) columns wrapped with Polyethylene Naphthalate fiber reinforced polymer (PEN FRP, a kind of large-rupture-strain FRP) and conventional CFRP. A total of seven columns were designed and fabricated, including a control column, three columns strengthened with CFRP, and three columns strengthened with PEN FRP. All columns were subjected to cyclic lateral load and a constant high axial load. The effectiveness of PEN FRP strengthening was systematically analyzed and discussed regarding the failure mode, displacement ductility, lateral cyclic load–displacement curve, stiffness degradation and energy dissipation capacity. The test results indicated that the control column exhibited inferior ductility and peak lateral strength, while FRP-strengthened columns possess better energy dissipation capacity and ductility. Further study found that PEN FRP was preferred to CFRP with similar tensile stiffness in seismic strengthening. Finally, based on the cyclic compression model of LRS FRP-strengthened concrete, the improved tensile model of FRP-strengthened concrete, and the cyclic stress–strain model of reinforcing steel, numerical simulations for seismic performance were carried out in OpenSees. It was found that the numerical simulation results of all FRP-strengthened RC columns were in excellent agreement with the test results. To better understand the effect of FRP confinement stiffness on the seismic performance of circular columns, parametric analysis was performed. Results showed that the numerical simulations need to consider the buckling of longitudinal reinforcement for accurately predicting the seismic behavior of FRP-strengthened columns of lower confinement stiffness. [ABSTRACT FROM AUTHOR]

AMP-activated kinase (AMPK) is a fuel-sensing enzyme present in most mammalian tissue. In response to a decrease in the energy state of a cell AMPK is phosphorylated and activated by still poorly characterized upstream events. Exposure of bovine aortic endothelial cells (BAEC) to chemically synthesized ONOO[sup -] acutely and significantly increased phosphorylation of c-Src, PDK1, AMPK, and its downstream target, acetyl-CoA carboxylase (ACC), without affecting cellular AMP. This novel pathway for AMPK activation was confirmed by the use of pharmacological inhibitors and dominant-negative mutants. Exposure of BAEC to hypoxia-reoxygenation (H/R) caused a biphasic increase in AMPK and ACC phosphorylation, which was prevented by adenoviral overexpression of superoxide dismutase (SOD) or inhibition of nitric-oxide synthase (NOS) implicating a role of ONOO[sup -] formed during H/R. Furthermore, dominant-negative mutants of c-Src or kinase-defective PDK1 also blocked H/R-induced AMPK activation indicating that, as with addition of exogenous ONOO[sup -], both c-Src and PI 3-kinase are upstream of AMPK. Moreover, H/R, like ONOO[sup -], significantly increased co-immunoprecipitation of AMPK with c-Src, suggesting that ONOO[sup -] favors physical association of AMPK with upstream kinases. Taken together, our results indicate a novel pathway by which H/R via ONOO[sup -] activates AMPK in a c-Src-mediated, PI 3-kinase-dependent mannet, and suggest that ONOO[sup -]-induced activation of AMPK might thereby regulate metabolic enzymes, such as ACC. [ABSTRACT FROM AUTHOR]

The overexpression of P-glycoprotein (P-gp) causes resistance to chemotherapy in human ovarian cancer. However, the underlying mechanism remains unclear. In the present study, we showed that, at membrane-bound protein level, P-gp was 'shared' between human ovarian cancer cells by the intercellular transfer of microvesicles (MVs). Paclitaxel-resistant human ovarian cancer cells (A2780/PTX) readily formed and released P-gp-containing MVs into the extracellular space compared with the wild-type parental line (A2780/WT). Shedding MVs bound to the chemosensitive A2780/WT cells in a time- and dose-dependent manner, transferring P-gp via the microenvironment. MV-mediated transfer of P-gp led to redistribution of the chemotherapeutic drug adriamycin in recipient cells (A2780/WT), which displayed 5- and 5-fold higher resistance to adriamycin and paclitaxel, respectively. Thus, these findings demonstrate a new mechanism of drug-resistance acquisition via MVs. [ABSTRACT FROM AUTHOR]

Visceral obesity is an independent risk factor for metabolic syndrome, and abnormal fat accumulation is linked to increases in the number and size of adipocytes. MiR-146b was a miRNA highly expressed in mature adipocytes while very lowly expressed in human mesenchymal stem cells (hMSCs) and human visceral preadipocytes (vHPA). In this paper, we mainly focused on the roles of miR-146b in adipogenesis. We found miR-146b could inhibit the proliferation of visceral preadipocytes and promote their differentiation. MiR-146b in human visceral adipocytes inhibited the expression of KLF7, a member of the Kruppel-like transcription factors, as demonstrated by a firefly luciferase reporter assay, indicating that KLF7 is a direct target of the endogenous miR-146b. MiR-146b expression was significantly altered in visceral and subcutaneous adipose tissues in human overweight and obese subjects, and in the epididymal fat tissues and brown fat tissues of diet-induced obese mice. Our data indicates that miR-146b may be a new therapeutic target against human visceral obesity and metabolic dysfunction. [ABSTRACT FROM AUTHOR]

Collagen is an insoluble protein that widely distributes in the extracellular matrix of marine animals. Collagen degradation is an important step in the marine nitrogen cycle. However, the mechanism of marine collagen degradation is still largely unknown. Here, a novel subtilisin-like collagenolytic protease, myroicolsin, which is secreted by the deep sea bacterium Myroides profundi D25, was purified and characterized, and its collagenolytic mechanism was studied. Myroicolsin displays low identity (<30%) to previously characterized subtilisin-like proteases, and it contains a novel domain structure. Protein truncation indicated that the Pro secretion system C-terminal sorting domain in the precursor protein is involved in the cleavage of the N-propeptide, and the linker is required for protein folding during myroicolsin maturation. The C-terminal β-jelly roll domain did not bind insoluble collagen fiber, suggesting that myroicolsin may degrade collagen without the assistance of a collagen-binding domain. Myroicolsin had broad specificity for various collagens, especially fish-insoluble collagen. The favored residue at the P1 site was basic arginine. Scanning electron microscopy and atomic force microscopy, together with biochemical analyses, confirmed that collagen fiber degradation by myroicolsin begins with the hydrolysis of proteoglycans and telopeptides in collagen fibers and fibrils. Myroicolsin showed strikingly different cleavage patterns between native and denatured collagens. A collagen degradation model of myroicolsin was proposed based on our results. Our study provides molecular insight into the collagen degradation mechanism and structural characterization of a subtilisin-like collagenolytic protease secreted by a deep sea bacterium, shedding light on the degradation mechanism of deep sea sedimentary organic nitrogen. [ABSTRACT FROM AUTHOR]

The aim of the present study was to report the short- and long-term clinical outcomes of percutaneous coronary intervention in young women with premature coronary artery disease. From February 2003 to December 2011, 168 consecutive women aged ≤45 years who underwent percutaneous coronary intervention with stent implantation were retrospectively analyzed. The primary end point was the incidence of major adverse cardiac events (MACEs) at short- and long-term follow-up. The mean age was 40.3 ± 2.0 years. Conventional coronary artery disease risk factors were common. Autoimmune or connective tissue diseases were present in 6.5% of the population, 4% had gynecologic diseases, 4 were postpartum, and 9 were taking contraceptives. The left anterior descending coronary artery was the most commonly affected vessel (83.3%) and the most common target vessel for stenting (76.8%). A total of 268 stents were implanted, 95.3% of which were drug-eluting stents. During the hospital stay, 1 patient died, and the incidence of MACEs was 1.2%. No additional events had occurred at 30-day follow-up. After a median follow-up duration of 36 months (interquartile range 12 to 60), cumulate MACE-free survival was 80.5%, the rate of target vessel revascularization was 16.5%, and the rate of stent thrombosis was 3.6%. Cox regression showed that hypertension, smoking, a left ventricular ejection fraction <50%, anterior myocardial infarction, and autoimmune disease were independent predictors of MACEs. In conclusion, percutaneous coronary intervention in young women tends to result in an increased rate of target vessel revascularization during long-term follow-up, which may be influenced by conventional and nonconventional risk factors. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report on the facile synthesis method to obtain nickel titanate (NiTiO3) nanoparticles through pyrolysis of polymeric precursor. The pyrolysis behaviors of the polymer precursors prepared via the in situ polymerization of metal salts and acrylic acid were analyzed by simultaneous thermogravimetric and differential scanning calorimetry. The structural and morphological characteristics of the products were studied by powder X-ray diffraction and transmission electron microscope. The results reveal that ilmenite NiTiO3 nanoparticles with spherical-like shape are obtained through pyrolysis of Ni–Ti polyacrylate precursor at above 600°C. The mean particle size of NiTiO3-600°C and NiTiO3-800°C is about 30nm and 60nm, respectively. Ultraviolet–visible (UV–vis) near infrared (NIR) reflectance spectra study show that the NiTiO3 nanoparticles have a high reflection peak of ~580nm, which is associated with the deep and brilliant yellow color of this pigment. The average reflectance of NiTiO3-600°C and NiTiO3-800°C in NIR range are 62.1% and 58.8%, respectively. We have observed brilliant yellow color and high UV–vis-NIR reflectance of NiTiO3 nanoparticles. Moreover, these NiTiO3 nanoparticles have great potential in serving as cool pigment for building coating. [Copyright &y& Elsevier]

Purpose: To examine whether ionizing radiation enhances the migratory and invasive abilities of cancer cells through transforming growth factor (TGF-β)–mediated epithelial–mesenchymal transition (EMT). Methods and Materials: Six cancer cell lines originating from different human organs were irradiated by 60Co γ-ray at a total dose of 2 Gy, and the changes associated with EMT, including morphology, EMT markers, migration and invasion, were observed by microscope, Western blot, immunofluorescence, scratch assay, and transwell chamber assay, respectively. Then the protein levels of TGF-β in these cancer cells were detected by enzyme-linked immunosorbent assay, and the role of TGF-β signaling pathway in the effect of ionizing radiation on EMT was investigate by using the specific inhibitor SB431542. Results: After irradiation with γ-ray at a total dose of 2 Gy, cancer cells presented the mesenchymal phenotype, and compared with the sham-irradiation group the expression of epithelial markers was decreased and of mesenchymal markers was increased, the migratory and invasive capabilities were strengthened, and the protein levels of TGF-β were enhanced. Furthermore, events associated with EMT induced by IR in A549 could be reversed through inhibition of TGF-β signaling. Conclusions: These results suggest that EMT mediated by TGF-β plays a critical role in IR-induced enhancing of migratory and invasive capabilities in cancer cells. [Copyright &y& Elsevier]

Abstract: In this article, transparent Al doped ZnO (AZO)/epoxy composite, as glass thermal insulation coating, was prepared by incorporating AZO nanoparticles into a transparent epoxy matrix. First, the as-synthesized AZO nanoparticles by the polymer pyrolysis method were characterized and the effect of Al doping content on the electrical conductivity of AZO nanoparticles was investigated. The results reveal that the AZO nanoparticles doped with 6mol% Al obtained from calcination at 600°C show the optimal electrical conductivity. The effects of AZO content on the optical and thermal insulation property of AZO/epoxy coating were also studied. It is shown that the AZO/epoxy composite coating with 0.5wt% AZO possesses excellent optical properties, i.e. visible light transmittance above 50% and shading coefficient of 0.45 are simultaneously achieved. In addition, the large temperature difference between the chambers coated respectively with the AZO/epoxy coated glasses and the common glass indicates that the prepared AZO/epoxy coating has an excellent thermal insulation property. [Copyright &y& Elsevier]

Abstract: In this article, antimony-doped tin oxide (ATO) nanoparticles was synthesized by a facile polymer-pyrolysis method. The pyrolysis behaviors of the polymer precursors prepared via in situ polymerization of metal salts and acrylic acid were analyzed by simultaneous thermogravimetric and differential scanning calorimetry (TG–DSC). The structural and morphological characteristics of the products were studied by powder X-ray diffraction (XRD) and transmission electron microscope (TEM). The results reveal that the ATO nanoparticles calcined at 600°C show good crystallinity with the cassiterite structure and cubic-spherical like morphology. The average particle size of ATO decreases from 200 to 15nm as the Sb doping content increases from 5mol% to 15mol%. Electrical resistivity measurement shows that the resistivity for the 10–13mol% Sb-doped SnO2 nanoparticles is reduced by more than three orders compared with the pure SnO2 nanoparticles. In addition, due to its versatility this polymer-pyrolysis method can be extended to facile synthesis of other doped n-type semiconductor, such as In, Ga, Al doped ZnO, Sn doped In2O3. [Copyright &y& Elsevier]

Large rupture strain (LRS) fiber-reinforced polymers (FRP) composites with an elongation greater than 5% offer an attractive solution for seismic strengthening of reinforced concrete (RC) columns. For a quick and reliable design of LRS FRP-strengthened RC columns, this paper presents a simplified plasticity damage model for LRS FRP-confined concrete under cyclic axial compression. This model consists of two parts: (a) a recent monotonic LRS FRP-confined concrete model developed by the authors' group as an envelope curve and (b) a simplified linear plasticity damage cyclic rule for predicting unloading and reloading paths. To solve the cyclic model deviation induced by concrete softening under a large axial strain, a pseudo-plastic strain was proposed, based on which the damage degradation of FRP-confined concrete can be quantified. The model comparisons show that although the proposed model sacrificed some precision when directly applied for the cyclic axial compressive behavior of FRP-confined concrete, it can give similarly accurate predictions as a complex model does for the behavior of conventional or LRS FRP-jacketed RC columns under a combined axial load and cyclic lateral load. Thus, this simplified plasticity damage model serves as a promising basic model for simulation of the seismic performance of FRP-strengthened structures. [ABSTRACT FROM AUTHOR]

Large rupture strain fiber-reinforced polymers (LRS FRPs) (e.g., with an elongation larger than 5%) provide ideal confinement for seismic retrofit of concrete columns. Most of existing design-oriented models for FRP-confined concrete define the slope of axial stress-strain curve (i.e., axial stiffness) as a function of FRP's rupture strain. Consequently, concrete confined with FRP of the same jacket stiffness but different rupture strains usually lead to different axial stiffnesses, which is contrary to the experimental observations. For LRS FRP-confined concrete a slight deviation in the axial stiffness might cause significant error in predicting its ultimate state. Therefore, a design-oriented model is developed here to define axial stiffness using the jacket stiffness rather than its rupture strain. 26 LRS FRP-confined circular concrete cylinders are tested and added to a database of 36 existing specimens. Then an existing lateral-to-axial strain (dilation) relationship is upgraded based on the above database and a database on 113 conventional FRP-confined concrete cylinders. A three-fold approach is employed to define the full-range stress-strain relation of LRS FRP-confined concrete as a function of jacket stiffness. The proposed stiffness-based design-oriented model predicts both softening and hardening behaviors and is applicable to both conventional and LRS FRP-confined concrete columns. [ABSTRACT FROM AUTHOR]