bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic Analysis of a Three‐Dimensional Singular Perturbed Predator–Prey Model With Multiple Factors
Authors: Li Zhenlei , Zhang Yue 
Published: February 2025

ABSTRACTIn this paper, the dynamic properties of a three‐dimensional singular perturbed predator–prey model with constant harvest, refuge effect, and cooperative hunt are discussed. The system has different bifurcation phenomena at the boundary equilibrium and the internal equilibrium. For the three‐time scale system, the small amplitude oscillations phenomenon is produced when the folded node coincides with the ordinary singularity, and its subsystem produces canard cycle without head when we select as a fixed number. Then we consider the change of two perturbation parameters; the system produces an oscillation phenomenon similar to relaxation oscillation, and with the change of perturbation parameters, the system trajectory appears single cycle, double cycles, and chaos. In addition, we consider the dynamic properties of the subsystem and the influence of stochastic factors on the subsystem.
A New Method for Event‐Triggered Synchronization of Fractional‐Order Delayed BAM Neural Networks in Finite Time
Authors: Xu Shangbin , Zhang Hai , Ye Renyu , Wu Xiang , Cao Jinde 
Published: February 2025

ABSTRACTThis article aims to study the finite‐time synchronization (FTS) problem of a class of bidirectional associative memory neural networks (BAMNNs) with time delays. Initially, leveraging properties of fractional calculus and common inequality techniques, a novel fractional FTS lemma is rigorously derived, which extends many existing FTS lemmas. Subsequently, an event‐triggered control (ETC) mechanism is devised, and with the aid of the newly established FTS lemma, sufficient conditions for achieving FTS in BAMNNs are formulated. Ultimately, the accuracy of the derived results is verified by a computational illustration.
Short‐Term Bovine Ovarian Tissue Heterotopic Autotransplantation: VEGF Beneficial and Detrimental Effects
Authors: Morais Ana N. P. , Souza Samara S. , Aguiar Francisco L. N. , Gastal Gustavo D. A. , Brandão Fabiana A. S. , Souza Juliany A. , Ñaupas Lucy V. S. , Alves Kele A. , Alves Benner G. , Gastal Melba O. , Rodrigues Ana P. R. , Figueiredo José R. , Teixeira Dárcio Í. A. , Gastal Eduardo L. 
Published: February 2025

ABSTRACTOvarian tissue transplantation (OTT) has been suggested as an alternative to preserving female fertility in livestock species, as currently performed in women. The OTT technique has been tested as xenografting or autografting in different body sites and animal species. Currently, there are no reports available regarding the autotransplantation of ovarian tissue using the bovine model and also testing the effect of vascular endothelial growth factor (VEGF) on graft survival. This study evaluated the effects of ovarian tissue short‐term exposure to VEGF before heterotopic autotransplantation into a subcutaneous site (flank region) for 7 days in cattle. The initial finding was that after OTT and without pre‐exposure to VEGF, the ovarian grafts had 42% of normal preantral follicles, which indicates a substantial step forward for this technique in cattle. Furthermore, VEGF exposure actively facilitated the process of neoangiogenesis, the proliferation capability of the stromal cells for activation of the cell cycle, maintained the balance between types I and III collagen fibers, and reduced the total collagen of the grafted tissue. Moreover, ovarian fragments previously exposed to VEGF tended to have greater follicular density; however, a detrimental effect of VEGF on follicular morphology was noticed. In conclusion, this study marks a significant step forward in bovine OTT and provides a foundation for further investigations into the specific pathways, stages, and durations of VEGF exposure to unveil strategies for refining ovarian transplantation techniques in cattle and other species.
Dynamic Modeling and Simulations of Molecular Weight Distributions In Continuous Stirred Tank Reactors for Solution Polymerization of Methyl Methacrylate
Authors: Robinson Benjamin , Choi Kyu Yong 
Published: February 2025

AbstractThe finite molecular weight moments (FMWM) technique, originally developed for calculating the complete molecular weight distribution (MWD) in batch free radical polymerizations, is extended here to simulate transient changes in MWD in a series of continuous flow stirred‐tank solution polymerization reactors. Unlike the classical method of molecular weight moments, which only calculates molecular weight averages, the FMWM technique provides a simple and effective means to calculate the whole shape of the polymer molecular weight distribution curve, even during the transient period of reactor operations in continuous processes. In this work, the solution polymerization of methyl methacrylate is used as a model system to demonstrate that the FMWM technique can successfully simulate transient MWDs, particularly bimodal distributions of polymer molecular weight resulting from varying reactor operating conditions in a series of two consecutive continuous stirred‐tank reactors operating at different temperatures. The simulation results reveal several interesting aspects of how polymer MWD changes over time in each reactor.
Using deep feature distances for evaluating the perceptual quality of MR image reconstructions
Authors: Adamson Philip M. , Desai Arjun D. , Dominic Jeffrey , Varma Maya , Bluethgen Christian , Wood Jeff P. , Syed Ali B. , Boutin Robert D. , Stevens Kathryn J. , Vasanawala Shreyas , Pauly John M. , Gunel Beliz , Chaudhari Akshay S. 
Published: February 2025

AbstractPurposeCommonly used MR image quality (IQ) metrics have poor concordance with radiologist‐perceived diagnostic IQ. Here, we develop and explore deep feature distances (DFDs)—distances computed in a lower‐dimensional feature space encoded by a convolutional neural network (CNN)—as improved perceptual IQ metrics for MR image reconstruction. We further explore the impact of distribution shifts between images in the DFD CNN encoder training data and the IQ metric evaluation.MethodsWe compare commonly used IQ metrics (PSNR and SSIM) to two “out‐of‐domain” DFDs with encoders trained on natural images, an “in‐domain” DFD trained on MR images alone, and two domain‐adjacent DFDs trained on large medical imaging datasets. We additionally compare these with several state‐of‐the‐art but less commonly reported IQ metrics, visual information fidelity (VIF), noise quality metric (NQM), and the high‐frequency error norm (HFEN). IQ metric performance is assessed via correlations with five expert radiologist reader scores of perceived diagnostic IQ of various accelerated MR image reconstructions. We characterize the behavior of these IQ metrics under common distortions expected during image acquisition, including their sensitivity to acquisition noise.ResultsAll DFDs and HFEN correlate more strongly with radiologist‐perceived diagnostic IQ than SSIM, PSNR, and other state‐of‐the‐art metrics, with correlations being comparable to radiologist inter‐reader variability. Surprisingly, out‐of‐domain DFDs perform comparably to in‐domain and domain‐adjacent DFDs.ConclusionA suite of IQ metrics, including DFDs and HFEN, should be used alongside commonly‐reported IQ metrics for a more holistic evaluation of MR image reconstruction perceptual quality. We also observe that general vision encoders are capable of assessing visual IQ even for MR images.
Friction and Wear Characterizations in Electrospun Nanofibrous Scaffolds for Cartilage Engineering
Authors: Souza Plath André Mathias , Alinezhadfar Mohammad , Ferguson Stephen J. 
Published: February 2025

ABSTRACTElectrospun nanofibers are promising materials to treat articular cartilage (AC) defects. However, they still have lower mechanical properties than tissue. There are no standard protocols to test friction in electrospun materials. Only a few studies have reported electrospun mats’ coefficient of friction (COF). This work aims to evaluate COF and wear for electrospun mats using a universal testing tribometer. Stainless steel, polyoxymethylene (POM), and rubber balls were rubbed against poly(ε‐caprolactone) (PCL) mats. There was a statistically significant difference between metal and rubber/plastic. This is attributed to surface chemistry. POM countersurfaces were rubbed at 1, 10, and 50 mm/s. The results show a small COF reduction proportional to speed and stick‐and‐slip behavior. Finally, we tested a PCL‐zein‐based material for its water contact angle reduction from 120° to 60°. The results demonstrated the lubrication efficiency (20% COF reduction) and hydrophobic‐hydrophilic contacts (33% COF reduction). The study successfully evaluates electrospun mats’ tribological properties. This is followed by the perspective of shear and friction biostimulation in electrospun surfaces. Furthermore, at the tested loads, the material had AC‐like COFs at boundary lubrication conditions.
B0 Magnetic Field Conditions in the Human Heart at 3 T Across One Thousand Subjects: A Numerical Simulation Study
Authors: Shang Yun , Theilenberg Sebastian , Peng Boyu , Schreiber Laura M. , Einstein Andrew J. , Jambawalikar Sachin R. , Juchem Christoph 
Published: February 2025

ABSTRACTFunctional scans in cardiovascular magnetic resonance (CMR) adopting bSSFP sequences suffer from dark band artifacts due to B0 inhomogeneity. The best remedy to mitigate this issue is through cardiac B0 shimming. The development of an optimal B0 shim strategy for the human heart is hindered by a limited understanding of B0 conditions in clinical diagnostic orientations of CMR. Here, we present high‐resolution B0 distributions in cardiac imaging planes, derived from simulations utilizing high‐resolution computed tomography (CT) images from 1008 subjects, and present an oblique slicing method to derive such B0 distributions. This study also presents a theoretical analysis of spherical harmonic B0 shimming at 3 T using a static global approach and slice‐specific dynamic shim updating in the short‐axis view of human hearts. The characteristics of cardiac B0 conditions along with spherical harmonic shimming were correlated with the subjects' demographic parameters, with weak or no correlations, suggesting limited demographic commonality and predominantly subject‐specific characteristics in cardiac B0. The segmented lung volume shows more significant associations and relatively higher correlations with B0 conditions, indicating that B0 conditions in the heart rely on the anatomy surrounding the heart more than overall body shape and size. This research provides a basis for the development of optimized cardiac B0 shim strategies.
Mechanical Behavior Prediction of 3D‐Printed PLA/Wood Composites Using Artificial Neural Network and Fuzzy Logic
Authors: Ulkir Osman , Akgun Gazi , Karadag Arif 
Published: February 2025

ABSTRACTThis study presents a novel approach to optimize and predict the mechanical properties of 3D‐printed polylactic acid (PLA)/wood composites through artificial neural network (ANN) and fuzzy logic (FL) modeling. The research addresses the critical challenge of determining optimal process parameters in fused deposition modeling (FDM) of natural fiber composites. Using Taguchi's L27 orthogonal array, experiments were conducted with five key printing parameters: layer thickness (100–200–300 μm), printing speed (PS) (40–60–90 mm/s), raster angle (RA) (0°–45°–90°), infill density (ID) (30%–60%–90%), and nozzle temperature (NT) (190°C–200°C–210°C). Analysis revealed that RA and PS were the most influential parameters, contributing 41.86% and 40.92% to tensile and compressive strengths, respectively. The developed ANN model demonstrated exceptional prediction accuracy with R2 values of 99.94% for both tensile and compressive strengths, surpassing the FL model's performance (R2 = 97.16%). The development of these models is crucial for accurately predicting mechanical behavior, allowing for efficient process optimization without extensive physical testing. Both methods demonstrated high prediction accuracy. Validation tests revealed that maximum errors of 1.95% and 2.81% for ANN and FL, respectively. The findings contribute valuable insights for the development of high‐performance natural fiber composites and establish a foundation for future advanced manufacturing processes.
Fabrication of imine‐assisted self‐healing APDMS/AMWCNT elastomer and the application in flexible circuits
Authors: Li Jiujuan , Zheng Yu , Liu Yuanhao , Zhang Binbin , Tang Xianzhong , Hong Yan , Ye Yuanyuan , Wang Chong , Zhou Guoyun , Chen Yuanming , Du Yongjie , Yang Weiguo , Jiao Yu , Zou Min , He Wei 
Published: February 2025

AbstractIn this work, a self‐healing elastomer involving reversible imine bonds was synthesized by Schiff base reaction between the amino groups in amino‐modified polydimethylsiloxane (APDMS) and the aldehyde groups in 1,4‐diformylbenzene (DFB). The incorporation of amino‐modified multi‐walled carbon nanotube (AMWCNT) allowed for good dispersion of AMWCNT with few aggregates and effectively balanced the mechanical properties and self‐healing performance, achieving a mechanical strength of 132.3 kPa and a self‐healing efficiency (HE) of 99.87% at room temperature after 24 h. The reversible imine bond based on the Schiff base linkage promotes quick self‐healing upon damage without any external stimulus at room temperature. Through electroless deposition, copper and nickel patterns were formed on the surface of the elastomer, establishing conductive pathways. The average resistivity of the copper trace was 5.40 × 10−8 Ω·m (3.63 × 10−7 Ω·m for nickel trace), which is 3.18 times that of regular copper wire (5.19 times for regular nickel wire). Upon cleavage and self‐healing of the elastomer with copper lines, with the resistivity increment by 14.43% in average (11.01% for nickel wire). This work offers an alternative pathway to the development of self‐healable silicone elastomers for future flexible electronics.Highlights
Elastomer with balanced mechanical properties and self‐healing performance.
Recyclable elastomer through hot‐press treatment.
Copper patterns were electroless‐deposited on the elastomer.
Damaged pattern restored conductivity within 24 h at room temperature.
Enhanced electromagnetic shielding and thermal performance of GNP and boron nitride infused carbon fiber/PDMS composites through magnetic field‐induced GNP alignment
Authors: Parameswarreddy Gandluri , Kolukula Harshitha , Suematsu Hisayuki , Vinaya Kumar Asapu , Subramanian Venkatachalam , Sarathi Ramanujam , Verma Rishi , Sharma Archana 
Published: February 2025

AbstractThe present work is focused on the development of magnetic field‐assisted graphene nanoplatelets (GNP) alignment in boron nitride (BN) graded short carbon fiber/ PDMS composites for the enhancement of thermal, electrical properties and electromagnetic interference (EMI) shielding effectiveness in X‐band (8–12 GHz) frequency which can be used as a gasket material. A rotating magnetic field is used for the alignment of GNP in the polymer matrix while the sample is in the curing stage. Initially, BN filler is optimized using morphological study viz., x‐ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. It has been validated that BN with 3 wt% is an optimum filler loading having a better filler dispersion and higher filler orientation. Extending the study further on this optimized BN filler (3 wt%) in the composite, the paper also analyzes the influence of filler orientation. Electrical properties by I‐V characteristics, thermal properties by performing laser flash analysis, and thermography analysis are carried out. It is observed that the electrical and thermal conductivities are greatly influenced by the alignment of filler. The lateral alignment of filler (RMF‐L) samples has a uniform heat distribution and better heat transfer all over the sample. In addition, the RMF‐L sample has an enhancement of EMI shielding of 53.3 dB (i.e., 99.9995% attenuation) compared to the non‐oriented NMF sample with 45.3 dB. In summary, the lateral alignment of filler in the RMF‐L sample led to the efficient use of nanofiller in the application of EMI shielding with better thermal and electrical properties.Highlights
GNP is oriented using a rotating magnetic field for enhancement of properties.
Additionally, neighbor BN to GNP aligns with the GNP alignment force.
BN of 3 wt% filler is an optimum filler loading with GNP maximum alignment.
GNP alignment has a great influence on electrical and thermal properties.
The aligned GNP sample RMF‐L has better EMI shielding of 53.3 dB.
A rapid prediction model for composite bolted joints based on spring stiffness method and Simulink circuit simulation
Authors: Pang Huan , Li Xin , Zhang Hongyu , Wang Lechen , Xu Bo 
Published: February 2025

AbstractIn order to improve the efficiency of preliminary design and optimization of composite structures, a rapid response predictive model for evaluating the mechanical behavior of bolted composite joints under tensile loading was established using the spring stiffness method. This model enables the analysis of structural stiffness and strength, and allows for the rapid acquisition of load–displacement curves in bolted composite joints. To enhance the accuracy of predicting nonlinear behavior during loading, various factors such as joint clearances, multi‐stage friction, and composite laminate damage were considered. The accuracy of the model was validated using finite element simulations and experimental results. In addition, by implementing the circuit modeling method, the modularization of the connection structure was achieved, allowing for the flexible assembly of modules to generate various circuit models. The circuit model accurately predicts the ultimate damage load of the composite while requiring only 1.5 s of computation time. The reduction in prediction time makes the circuit model an effective and practical tool for analyzing the nonlinear behavior of composite joints. Moreover, the circuit model is applicable in preliminary structural optimization. The results demonstrate that using the circuit model enables optimization tasks to be completed in a short time frame.Highlights
A model that incorporates the effects of clearances, friction, and damage.
A significant advantage in simulation time (about 1.5 s) and cost.
A multi‐bolt joint model enables the calculation of damage and load distribution.
The circuit model was used to optimize the design of the three‐bolt joint.
Shear creep behavior of load transfer component for variable‐stiffness fiber‐reinforced polymer cable anchoring system
Authors: Zhou Jingyang , Cheng Caishu , Wang Xin , Jiang Kaidi , Ding Jian , Xu Qiwei , Wu Zhishen 
Published: February 2025

AbstractThe static shear properties and 1000‐h creep of load transfer components (LTCs) for anchoring cable was experimentally determined by considering the modified material, volume fraction, hybrid ratio, and stress level, respectively. 1000‐h and million‐hour creep strains were theoretically predicted. The effect of LTC creep on bonded anchorage relaxation was numerically analyzed. The results revealed that vacuuming increased shear strength by 20.8% to 43.6% and shear modulus by 3.1% to 16.0%. Adding fibers can concurrently increase both shear strength and shear modulus, while hybrid ratio had minimal impact on these properties. High stress can cause cracking of single quartz sand‐modified resin (SSMR). Adding fibers or sand can reduce resin creep but the deformation resistance of single glass microfiber‐modified resin (SFMR) surpassed that of SSMR. The creep coefficients of the plain and modified resins rapidly increased when stress levels reached 0.7 fu (fu = ultimate strength). Both the Findley and logarithmic models can reasonably forecast 1000‐h creep. Shear stress levels should be restricted below 0.5 fu to control creep. The experimental LTC strains can be accurately described by the established finite element model. Shear stress concentration showed an S‐shaped trend along the LTC thickness. Higher stress levels and greater LTC thickness led to increased stress losses.Highlights
The shear‐enhancing effect of fibers and sand was experimentally evaluated.
The 1000‐h and million‐hour shear creep coefficients of LTCs were revealed.
The effect of LTC creep on bonded anchorage relaxation was numerically clarified.
Modeling short fiber reinforced polymer matrix composite materials using material designer
Authors: Eyri Busra , Gul Okan , Karsli N. Gamze , Yilmaz Taner 
Published: February 2025

AbstractIn the present era, the importance of simulations pertaining to production is increasing in terms of cost, human resources, and time. As the majority of existing studies on polymer matrix composites are experimental, the development of a modeling approach for these materials will address a significant gap in the existing literature. In order to achieve this objective, the present study investigates the factors influencing the modeling of carbon fiber‐reinforced PPS composites produced by the injection molding method with the Ansys Material Designer tool. Composites containing 10% CF by weight were subjected to a tensile test subsequent to production. Subsequently, the tensile strength, elastic modulus, and tensile strain values obtained were then compared with the values were compared with those obtained from the modeled RVEs, with an examination of the various parameters in the Material Designer tool. The requisite parameter values for the optimal model, exhibiting the closest approximation to the experimental results, were derived from the modeled RVEs. The findings of the study indicated that the mean strength of the samples produced was measured at 143.73 MPa. However, when the optimum parameter conditions were met, this value was obtained at 141.48 MPa, with an error of 1.56% in the RVE model. However, this error increased to 18.58% in the elasticity modulus.Highlights
The mesh was found to have no significant impact on the outcomes.
The number of additives in the RVE had a direct effect on the results.
Changes in the fiber distribution demonstrated comparable outcomes.
The most crucial parameter for accurately modeling is the RVE size.
A Whole‐Population Comparative Study of the School Experience and Its Association With Depressive Symptoms Among Immigrant‐Origin and Native Preadolescents
Authors: Abdulhamed Rekar , Hietajärvi Lauri , Klemetti Reija , Lonka Kirsti 
Published: February 2025

ABSTRACTIn European studies, immigrant‐origin adolescents report more mental health symptoms than natives do. The school is an important developmental context for them, and more research is needed about how their school experience is related to their mental health symptoms, and whether these relations vary by group. The aim of this study was to assess the prevalence of depressive symptoms, and their association with the school experience among native and immigrant‐origin preadolescents attending the fourth and fifth grades of primary school. Whole‐population surveys of three time points (2017, 2019, 2021, N = 259,382, of which N = 14,930 immigrant‐origin) were used. Immigrant‐origin preadolescents were grouped by their birth country and their parents to first‐ and second‐generation, and to forced and voluntary immigrant groups. Depressive symptoms were most often reported by first‐generation immigrant preadolescents followed by their second generation counterparts. Sense of school belonging was the most important protective factor and bullying the most important risk factor in relation to depressive symptoms. Positive school experiences were more beneficial for the mental health of natives than their immigrant‐origin counterparts. In turn, negative school experiences were more detrimental for the mental health of immigrant‐origin preadolescents.