Engineering Structures最新文献

{"title":"3D-printed multi-functional sinusoidal metamaterials for simultaneous vibration isolation and electricity generation","authors":"Ramin Hamzehei ,&nbsp;Mahdi Alaei Varnosfaderani ,&nbsp;Mahdi Bodaghi ,&nbsp;Nan Wu","doi":"10.1016/j.engstruct.2025.121496","DOIUrl":"10.1016/j.engstruct.2025.121496","url":null,"abstract":"<div><div>This study introduces 3D-printed multi-functional sinusoidal metamaterials designed for simultaneous vibration isolation and electricity generation. The innovative design follows the sinusoidal patterns derived from re-engineered common auxetic re-entrant unit cells, resulting in multi-stiffness lattice structures. Layers of unit cells, with one rotated 90°, are integrated, facilitating local buckling in the vertical beams under compression. A quasi-zero-stiffness (QZS) mechanism, achieved through local buckling-induced nonlinearity, is incorporated to enhance vibration isolation. Two stabilizers are designed to maintain global structural stability under compression and dynamic loads, and the underlying deformation mechanisms are elucidated by finite element analysis (FEA) and experiments. Experimental evaluation reveals effective vibration isolation for frequencies above 15 Hz. For electricity generation, two piezoelectric materials are employed, namely Lead zirconate titanate (PZT) and piezo bender (PB). The flexible lattice structure, made from thermoplastic polyurethane (TPU), can withstand substantial bending deformations under a specific load and simultaneously apply bending forces to the PB. This leads to electricity generation at approximately 3 volts (V) and maximum generated power around 700 microwatts per gravity (<span><math><mfrac><mrow><mi>μ</mi><mi>W</mi></mrow><mrow><mi>g</mi></mrow></mfrac></math></span>) by one PB at a low frequency of 15 Hz, where vibration isolation arises. Meanwhile, one PZT, mounted on a polylactic acid (PLA)-based semi-honeycomb structure, generates energy due to higher dynamic forces caused by high-stiffness property of PLA, leading to electricity generation at around 500 millivolts (mV), and a maximum generated power of 800 <span><math><mfrac><mrow><mi>μ</mi><mi>W</mi></mrow><mrow><mi>g</mi></mrow></mfrac></math></span> at a high frequency of 90 Hz. The proposed metamaterials exhibit material-independent properties with multi-functional potentials for simultaneous vibration isolation and electricity generation. They support wearable applications, enabling motion tracking and injury prevention in protective gear through self-powered sensing. In civil structures, these hybrid metamaterials can be embedded in bridge joints, isolation pads, or foundations to reduce low-frequency vibrations and power wireless sensors for real-time, self-sustained structural health monitoring.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121496"},"PeriodicalIF":6.4,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Negative flexural performance of steel-UHPC composite deck with a novel grouped stud configuration addressing the shrinkage influence","authors":"Sheraz Abbas ,&nbsp;Han Xiao ,&nbsp;Chen Xu ,&nbsp;Wei Wang ,&nbsp;Biao Ma","doi":"10.1016/j.engstruct.2025.121474","DOIUrl":"10.1016/j.engstruct.2025.121474","url":null,"abstract":"<div><div>The shrinkage effect in steel-Ultra High Performance Concrete (UHPC) composite decks can lead to damage accumulation, potentially compromising the flexural performance and structural integrity of the composite system. A newly developed group stud configuration that is effective in reducing the early shrinkage-induced stress in steel-UHPC composite decks. A further study on the negative flexural performance of steel-UHPC composite deck with group stud configuration was conducted to reveal its mechanical performance and reliability. Two full-scale bridge deck segment specimens, with Conventional Uniform studs (SU) and Novel Grouped studs (SG) configurations, were investigated through static load tests under negative bending to evaluate the negative flexural performance. Additionally, simulations and parametric analysis were carried out to assess the impact of varying group stud spacing on flexural performance. The results indicate that the grouped stud arrangement not only reduces shrinkage-induced stresses but also improves crack control, while maintaining bending stiffness and ultimate load capacity comparable to the conventional unifrom stud arrrangment. Additionally, reinforcement yielding occurred at crack widths beyond 1.0 mm, highlighting the potential of the grouped stud configuration to improve serviceability and long-term durability in steel–UHPC composite decks. Similarly, Finite Element (FE) simulations successfully captured the stress distribution induced by shrinkage and the corresponding load-displacement behaviour. Parametric analysis revealed that shrinkage-induced stresses reduced the load capacity by 10 % in the uniform stud arrangement, whereas this effect was negligible in the grouped stud configuration. This study confirms that a grouped stud configuration mitigates shrinkage-induced stresses while maintaining comparable mechanical performance, providing important implications for the design of steel-UHPC composite bridge decks.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121474"},"PeriodicalIF":6.4,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic mitigation and configuration-based performance study on particle tuned mass damper applied to transmission tower-line system","authors":"Kunjie Rong ,&nbsp;Junrong Gong ,&nbsp;Zheng Lu ,&nbsp;Li Tian ,&nbsp;Yelei Shen ,&nbsp;Mengyao Zhou","doi":"10.1016/j.engstruct.2025.121490","DOIUrl":"10.1016/j.engstruct.2025.121490","url":null,"abstract":"<div><div>This study develops a finite-discrete element coupling simulation model to assess seismic mitigation effectiveness of particle tuned mass dampers (PTMDs) in transmission tower-line systems (TTLSs). The particle dynamics within the PTMD are investigated, and parametric analyses are conducted to explore the vibration control mechanism. A key indicator, the average pounding clearance, is proposed to reflect the influence of PTMD configuration on its damping performance. Results show that the simulation model, validated through shaking table tests, effectively captures the nonlinear vibration characteristics of both the TTLS and the PTMD. PTMD significantly reduces the seismic response of transmission towers in TTLS, achieving a maximum reduction ratio of 45.6 %. The pounding of particles within the PTMD can transfer vibration energy to higher frequencies, expediting energy dissipation. Furthermore, upper and lower numerical bounds can be found for particle displacement in a single-particle PTMD. However, these bounds are less strict for multiple-particle PTMDs, highlighting the limitation of the simplification method used in previous studies. The proposed indicator addresses the limitations of traditional parameters, such as area filling ratio, which fail to independently capture the impact of PTMD configuration on its damping performance.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121490"},"PeriodicalIF":6.4,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting local buckling in steel members under cyclic loads: A strain-based approach using the CSM","authors":"Yu Chen ,&nbsp;Christian Málaga-Chuquitaype ,&nbsp;Feng Zhou ,&nbsp;Leroy Gardner","doi":"10.1016/j.engstruct.2025.121473","DOIUrl":"10.1016/j.engstruct.2025.121473","url":null,"abstract":"<div><div>A new approach, based on the Continuous Strength Method (CSM), is presented for the prediction of cross-section failure through inelastic local buckling in steel members under cyclic loading. Cross-section local buckling failure is predicted to occur when a prescribed strain limit is reached; the effect of loading history is accounted for by considering the cumulative strain from each loading cycle. The strain limit is related to the cross-section slenderness, which is based on the local buckling behaviour of the full cross-section, rather than the individual plate width-to-thickness ratios, making it suitable for different section profiles (e.g., hollow sections and I-sections). Finite element models are established, validated and used to conduct parametric studies, covering a series of steel grades, a wide range of cross-section slendernesses and various cyclic axial loading protocols. The resulting numerical data sets are employed to develop a means of rationally considering the contribution of both the compressive and tensile strain ranges in each loading cycle to cross-section failure. The suitability of the newly proposed method is verified against experimental results on beam-columns with hollow sections and I-sections under cyclic loading, as well as numerical results. The findings indicate that the cumulative deformation capacity and local buckling failure of steel cross-sections can be accurately predicted using the developed strain-based design method. The method can be applied in the inelastic analysis of structures under seismic loading and in the seismic design of steel cross-sections.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121473"},"PeriodicalIF":6.4,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploration of Multi-Fidelity Co-Kriging and Real-Time Hybrid Simulation for Time-Dependent Seismic Performance Evaluation","authors":"Guangquan Yu ,&nbsp;Weijie Xu ,&nbsp;Changle Peng ,&nbsp;Cheng Chen ,&nbsp;Tong Guo","doi":"10.1016/j.engstruct.2025.121497","DOIUrl":"10.1016/j.engstruct.2025.121497","url":null,"abstract":"<div><div>Real-time hybrid simulation (RTHS) divides the structure under investigation into experimental and numerical substructures thus facilitates large- or even full-scale experiments beyond laboratory constraints. Traditional analysis of time-varying uncertainties necessitates extensive RTHS experiments in laboratories when parts of structures are difficult for accurate modeling due to their complexity and/or nonlinearity. To address this challenge, this study explores Co-Kriging meta-modeling and adaptive sampling with RTHS aiming for efficient time-dependent performance evaluation with limited number of RTHS tests in laboratories. The expansion optimal linear estimation method is applied to discretize random processes for time-varying uncertainties. Key informative sample points are selected through an adaptive sampling technique, while the Co-Kriging meta-model combines low-fidelity numerical simulations with high-fidelity RTHS experiments to account for time-varying uncertainties in structural response prediction. A single-degree-of-freedom structure with time-varying stiffness degradation is used in this pilot study to experimentally evaluate the accuracy and efficiency of proposed multi-fidelity approach. It is demonstrated that the Co-Kriging meta-modeling provides a promising alternative for efficient time-dependent performance evaluation to account for time-varying uncertainties especially when parts of structure are difficult for numerical modeling. Compared with single fidelity based method such as Kriging, Co-Kriging provides faster convergence thus leading to less laboratory tests.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121497"},"PeriodicalIF":6.4,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fire performance and post-fire residual behavior of insulated CFRP shear-strengthened RC beams: An experimental and numerical study","authors":"Wan-Yang Gao ,&nbsp;Jun-Cong Lin ,&nbsp;Ke-Xu Hu ,&nbsp;Jian Yang","doi":"10.1016/j.engstruct.2025.121480","DOIUrl":"10.1016/j.engstruct.2025.121480","url":null,"abstract":"<div><div>This paper presents an experimental and numerical study on the fire performance and post-fire residual behavior of reinforced concrete (RC) beams shear-strengthened with carbon fiber-reinforced polymer (CFRP) U-wraps. Seven full-scale beams were tested, including three specimens under ambient conditions and four subjected to ISO 834 standard fire exposure. The key experimental variables included fire exposure duration, number of CFRP U-wrap layers, shear span-to-depth ratio and the presence of a 20 mm fire-resistant mortar insulation layer. Experimental results showed that the CFRP U-wraps increased the shear capacity of the specimens by approximately 30 %–35 % under ambient conditions. In fire tests, the uninsulated RC beam failed due to diagonal shear cracking, whereas the insulated CFRP shear-strengthened RC beams maintained their structural integrity for a fire resistance rating of 2.5 h, exhibiting only small midspan deflections. Subsequent post-fire bending tests showed that the insulation layer effectively preserved the residual shear capacity of the strengthened beams, maintaining values comparable to their pre-fire capacities. A coupled thermal-mechanical numerical model was proposed by integrating transient heat transfer analysis with a fiber-based sectional method to predict the temperature distribution within the beam cross-section and to quantify the degradation of shear capacity during and after fire exposure. The model explicitly accounted for the temperature-dependent deterioration of concrete, steel stirrups and CFRP U-wraps as well as the bond behavior between the CFRP and the concrete substrate. Numerical predictions showed close agreement with the experimental results, which validated the accuracy and reliability of the proposed numerical model. The validated model offers a robust analytical framework for evaluating the in-fire and post-fire shear performance of CFRP shear-strengthened RC beams, thereby supporting the development of performance-based fire-resistance design provisions for such members.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121480"},"PeriodicalIF":6.4,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic response of steel moment connections to built-up box columns with varied diaphragm designs","authors":"Alejandro Santiago-Flores ,&nbsp;Edgar Tapia-Hernández","doi":"10.1016/j.engstruct.2025.121495","DOIUrl":"10.1016/j.engstruct.2025.121495","url":null,"abstract":"<div><div>This study investigates the seismic behavior of steel moment connections between I-shaped beams and built-up box columns incorporating internal, through, and external diaphragm configurations. These connection types were evaluated through full-scale cyclic tests and nonlinear finite element analysis (FEA). The experimental program assessed cumulative ductility, energy dissipation, and failure mechanisms, revealing that diaphragm placement critically influences plastic hinge formation and damage concentration. Specimens with external diaphragms demonstrated superior ductility and energy dissipation, while internal and through diaphragm configurations exhibited brittle fracture near the column face. Fractographic and metallographic analyses confirmed that failure was driven by geometric detailing rather than weld defects or material inconsistencies. A unified multilinear envelope curve was proposed to model the force-deformation behavior of these connections, addressing gaps in current design standards. The findings offer practical recommendations for diaphragm detailing and nonlinear modeling of box-column connections under seismic demands.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121495"},"PeriodicalIF":6.4,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Underwater shaking table test on seismic responses of deep-water bridge pier considering the effect of constraint boundary at pier top","authors":"Kun Wu ,&nbsp;Yu Chen ,&nbsp;Xin Huang ,&nbsp;Bo Zhao ,&nbsp;Zhong-Xian Li","doi":"10.1016/j.engstruct.2025.121487","DOIUrl":"10.1016/j.engstruct.2025.121487","url":null,"abstract":"<div><div>The water-pier interaction remarkably affects the seismic performance of deep-water bridges. There are many studies on the dynamic responses and damage analysis on the water-pier coupling system. However, many studies on the water-pier interaction assumes a free boundary at pier top, while there is a constraint at pier top in the real engineering. The boundary condition significantly affects the responses of the pier under earthquake according to the structural dynamics. In this study, a series of underwater shaking table tests were conducted to investigate the responses of deep-water pier considering the effect of constraint boundary at pier top. The model pier was designed and assembled with a specially-made rubber material. The seismic responses of pier were measured under ground motions with various characteristics. The results declared that the proposed test scheme was effective to provide a displacement constraint at the pier top. The constraint boundary increased the natural vibration frequency, hydrodynamic pressure, acceleration, and relative displacement of pier and decreased the strain of pier. As the constraint stiffness at pier top changed from 0 to 200 kN/m, the natural vibration frequency increased by up to 140.0 % and the responses of pier increased by up to 375.3 %. The earthquakes with pulse effect increased the responses of pier by up to 176.8 % then those without pulse effect. The seismic responses of the pier increased by up to 60.0 % when the water depth changed from 0 to 2.0 m. The effect of constraint boundary at pier top should be considered in the design of deep-water bridge.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121487"},"PeriodicalIF":6.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A method for investigating the responses of cable-stayed bridge exposed to distinctive tank truck fires","authors":"Hao Wan,&nbsp;Gang Zhang,&nbsp;Yuhang Ding","doi":"10.1016/j.engstruct.2025.121481","DOIUrl":"10.1016/j.engstruct.2025.121481","url":null,"abstract":"<div><div>This paper designs novel tank truck fires on deck and establishes a fire-structural calculation method for cable-stayed bridges. The designed fires include tank fire, spill fire, and their combined fire, the features of fire sources are configured based on surface conditions of deck and thickness of fuel. The established calculation method is traced in three stages, reproducing tank truck fires on deck by fire dynamics model, simulating thermal conduction in finished cables via heat transfer model, and analyzing thermal-mechanical performances of entire bridge through multi-scale finite element model. The calculation process of fire-exposed cables is experimentally validated and utilized for capturing fire responses of a cable-stayed bridge under the three fire scenarios. The main findings indicate that, tank fire causes a more significant reduction in force on several cables before their fracture than spill fire; spill fire eventually induces the fracture of more cables than tank fire; their combined fire contains the differences in fire behaviors of tank fire and spill fire; and a steeper deflection or rotation increment eventually occurs under spill fire or combined fire. The designed tank truck fires and the proposed calculation method provide an accessible approach for evaluating fire responses of cable-stayed bridges.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121481"},"PeriodicalIF":6.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Full-scale dynamics and water-tightness tests of a closed cavity double skin curtain wall","authors":"Kehinde J. Alawode ,&nbsp;Amal Elawady ,&nbsp;Seung Jae Lee ,&nbsp;Arindam Gan Chowdhury ,&nbsp;Guido Lori","doi":"10.1016/j.engstruct.2025.121498","DOIUrl":"10.1016/j.engstruct.2025.121498","url":null,"abstract":"<div><div>Traditional double skin curtain walls have been around for a while and are mostly designed as pressure equalized rain screens with cavity openings to the external climate. Cavity permeability which is formed by both intentional and non-intentional openings (i.e., holes or defects, respectively) impacts the pressure equalization rate and wind load sharing ratio between the two skins. Cavity permeability is also known to affect the weather-tightness of the building envelope. Recently, a double skin curtain wall with a closed cavity, also referred to as a Closed Cavity Façade (CCF) was developed in the façade industry. Compared to the traditional double skin curtain wall, the closed cavity curtain wall has at least two orders of magnitude lower cavity permeability. Currently, there is no guidance on the wind load sharing for this newly developed closed cavity curtain wall, neither are any details on the behaviour of the units when there are defects that lead to a higher cavity permeability. To date, the water tightness of these units using realistic rain and strong winds has not been investigated systematically. To improve the understanding of the behaviour (wind-induced vibrations, water penetration due to wind-driven rain, and load sharing) of this closed cavity system, full-scale wind tunnel testing is carried out on this unit at the NHERI Wall of Wind Experimental Facility. The tests were conducted at 22.4 m/s, 31.3 m/s and 40.2 m/s wind speeds with wind directions from 0° to 180° in 15° increments. This study shows the dependence of the cavity pressure on wind speeds when there are defects. Also, higher pressure fluctuations leading to higher loads on the external glazing are observed. Higher dynamic amplification is associated with the non-defective units. Load sharing is observed to be dependent on the stiffness and permeability of the unit, while in a defective unit, it was also dependent on the wind speed. The closed cavity unit performed effectively under co-occurring wind and rain conditions when there was no defect.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"345 ","pages":"Article 121498"},"PeriodicalIF":6.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145218507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}