bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time-Resolved Echo-Particle Image/Tracking Velocimetry Measurement of Interactions Between Native Cardiac Output and Veno-Arterial ECMO Flows
Authors: Zhang Zeng , Zhou Xun , Suarez-Pierre Alejandro , Lui Cecillia , Kearney Sean , Yeung Enoch , Halperin Henry , Choi Chun Woo , Katz Joseph 
Published: September 2020

AbstractDetermination of optimal hemodynamic and pressure–volume loading conditions for patients undergoing veno-arterial extracorporeal membrane oxygenation (VA-ECMO) would benefit from understanding the impact of ECMO flow rates (QE) on the native cardiac output in the admixing zone, i.e., aortic root. This study characterizes the flow in the aortic root of a pig with severe myocardial ischemia using contrast-enhanced ultrasound particle image/tracking velocimetry (echo-PIV/PTV). New methods for data preprocessing are introduced, including autocontouring to remove surrounding tissues, followed by blind deconvolution to identify the centers of elongated bubble traces in images with low signal to noise ratio. Calibrations based on synthetic images show that this procedure increases the number of detected bubbles and reduces the error in their locations by 50%. Then, an optimized echo-PIV/PTV procedure, which integrates image enhancement with velocity measurements, is used for characterizing the time-resolved two-dimensional (2D) velocity distributions. Phase-averaged and instantaneous flow fields show that the ECMO flow rate influences the velocity and acceleration of the cardiac output during systole, and secondary flows during diastole. When QE is 3.0 L/min or higher, the cardiac ejection velocity, phase interval with open aortic valve, velocity-time integral (VTI), and mean arterial pressure (MAP) increase with decreasing QE, all indicating sufficient support. For lower QE, the MAP and VTI decrease as QE is reduced, and the deceleration during transition to diastole becomes milder. Hence, for this specific case, the optimal ECMO flow rate is 3.0 L/min.
Integrating Materials Model-Based Definitions into Design, Manufacturing, and Sustainment: A Digital Twin Demonstration of Incorporating Residual Stresses in the Lifecycle Analysis of a Turbine Disk
Authors: Gopalakrishnan Saikiran , Hartman Nathan W. , Sangid Michael D. 
Published: September 2020

Abstract
Model-based definitions (MBDs) aim to capture both geometric and non-geometric data in digital product definitions using 3D computer-aided design (CAD) models, as a form of product definition baseline, to disseminate product information across different stages of the lifecycle. MBDs can potentially eliminate error-prone information exchange associated with traditional paper-based drawings and improve the fidelity of component details, captured using 3D CAD models. A component’s behavior during its lifecycle stages influences its downstream performance, and if included within the MBD of a part, could be used to forecast performance upfront during the design and explore newer designs to enhance performance. However, current CAD capabilities limit associating behavioral information with the component’s shape definition. This paper presents a CAD-based tool to store and retrieve metadata using point objects within a CAD model, creating linkages to spatial locations within the component. The tool is illustrated for storage and retrieval of bulk residual stresses developed during the manufacturing of a turbine disk acquired from process modeling and characterization. Further, variations in residual stress distribution owing to process model uncertainties have been captured as separate instances of the disk’s CAD models to represent part-to-part variability as an analogy to track individual serialized components for digital twins. The propagation of varying residual stresses from these CAD models within the damage tolerance analysis performed at critical locations in the disk has been demonstrated. The combination of geometric and non-geometric data inside the MBD, via storage of spatial and feature varying information, presents opportunities to create digital twin(s) of actual component(s).
Bionic Flapping Mechanism of the Wings of a Cursorial Dinosaur Robot for Estimating Its Lift and Thrust
Authors: Song Hong-Wei , Talori Yaser Saffar , Zhao Jing-Shan 
Published: September 2020

AbstractWe estimated the lift and thrust of the proto-wings of the dinosaur Caudipteryx, a close relative of birds, using both theoretical and experimental approaches. Our experiments utilized a newly reconstructed flapping wing mechanism in accordance to the fossil specimens of Caudipteryx. To ensure that this reconstructed mechanism could adequately simulate the realistic flapping movements, we investigated the relationships among the flapping angle, twisting angle, and stretching angle of the wing mechanism that was driven by a DC motor. We also used two sensors to measure the lift and thrust forces generated by the flapping movements of the reconstructed wing. Our experiment indicated that both the lift and thrust forces produced by the wings were small but increased at higher flapping frequencies. This study not only contributes to current understanding of the origin of avian flight but also usefully informs the ongoing development of bionic flapping robots.
Finite Element Modeling of Electromagnetic Crimping of Cu-SS Tube-to-Tube Joint Along With Simulation of Destructive Testing for Strength Prediction of the Joint
Authors: Kumar Deepak , Kore Sachin D. , Nandy Arup 
Published: September 2020

Abstract
This work explores the tube-to-tube joining of copper (outer) and stainless steel (inner) using electromagnetic crimping. Stand-off distance is kept constant during all the experiments. ls-dynaTM electromagnetic module, which utilizes finite element method combined with the boundary element method, is used to perform numerical simulations and the model is validated with experimentally observed thinning and radial deformation of the outer tube during electromagnetic crimping. Effect of slit of the field shaper on Lorentz force distribution is studied. It is observed that the slit of the field shaper leads to uneven radial deformation. Furthermore, a novel finite element model has been developed to predict the pull-out and compressive strength of the joint. Results are validated with the experimentally observed data.
An Energy-Based Analysis for Machining Novel AZ91 Magnesium Composite Foam Dispersed With Ceramic Microspheres
Authors: Kannan S. , Pervaiz S. , Klassen R. J. , Huo D. , Haghshenas M. 
Published: September 2020

Abstract
Metal syntactic foams are a novel grade of materials that find potential applications in the manufacture of lightweight structural components and biomedical applications. For these materials to be inducted into industrial applications, it becomes imperative to study their machining behavior. In this article, for the first time in the literature, machining characteristics of AZ91 magnesium foam reinforced with thin-walled hollow alumina ceramic microspheres being studied. Through cutting experiments, it is found that finer the size of hollow microspheres and higher their volume fraction, higher was the magnitude of cutting forces recorded. The failure mechanisms that constituted chip formation during cutting AZ91 foam has been explicated through a mechanistic cutting force model. The proposed force model takes into account key hollow alumina microsphere properties such as wall thickness-to-diameter ratio, average microsphere size, and volume fraction. The scanning electron microscopic (SEM) analysis showed two key modes of failure during cutting metallic foams. Microsphere bursts and fractures control matrix plastic deformation through an effective load transfer mechanism. The transverse matrix cracks, which are initiated as a result of induced shear stress, promote the propagation of longitudinal adhesive cracks. This rapid crack growth takes place along the direction of maximum energy release rate, thus weakening the interfacial strength and reducing effective load transfer. This leads to microsphere separation, and further matrix densification due to the collapse of microsphere cavities leads to chip separation. The developed mechanistic model was in better agreement with experimental results.
Study of Overlapping Adjacent Jets for Effective Laser-Induced Forward Transfer Printing
Authors: Sole-Gras Marc , Xiong Ruitong , Liang Changxiao , Roorda William , Yamaguchi Hitomi , Huang Yong 
Published: September 2020

Abstract
Laser-induced forward transfer (LIFT) is a well-established, versatile additive manufacturing technology for orifice-free printing of highly viscous solutions and suspensions. In order to improve the efficiency of point-wise LIFT printing, an optical scanner is integrated into the laser printing system to enable the formation of overlapping adjacent jets used for deposition. The objective of this study is to evaluate the ejection behavior and deposition performance under such conditions during LIFT printing for further improvement. The effects of the overlap of adjacent jets are investigated in terms of jet formation and material deposition processes, capturing the jet tilting phenomenon caused by the perturbance induced by previously formed jet(s). The feasibility of optical scanner-assisted LIFT printing of viscous metal-based ink suspension has been successfully demonstrated during conductive line printing with induced overlapping jets. Investigation of various overlap ratios of adjacent jets found that a 30% jet overlap and a 133 µs time interval between laser pulses are optimal, in terms of deposition quality and ejection stability, even when a tilted jet ejection is present for the laser and material system in this study. Furthermore, multilayer polygonal and interdigitated structures are successfully deposited under these identified printing conditions. With the inclusion of an optical scanner, LIFT printing efficiency for viscous inks can be improved as the usage of higher laser frequencies is enabled, providing a faster orifice-free laser printing methodology.
Numerical Modeling of Powder Gas Interaction Relative to Laser Powder Bed Fusion Process
Authors: Li Xuxiao , Tan Wenda 
Published: September 2020

Abstract
The powder motion induced by the gas flow has been identified as one of the critical phenomena in laser powder bed fusion processes that significantly affect the build quality. However, the gas dynamics and its induced driving forces for the powder motions have not been well quantified. A numerical model is developed to investigate such powder-gas interactions. With a combination of computational fluid dynamics and particle tracking techniques, the model is capable of simulating the transient gas flow field surrounding the powder and the forces exerted on powder surfaces. The interaction between metal powders and a free jet is investigated with the current model. In the simulation results, the entrainment and the ejection motions of powders with respect to the free jet can be predicted. It is found that the driving forces of these motions are majorly contributed by the pressure differences in the gas flow surrounding the powder, and the powders can also interact with the jet to significantly alter the flow field. Quantities that are difficult to measure by experiments are quantified by the simulations, such as the velocity/pressure fields in the gas as well as the subjected forces and torques on powders. Such quantitative information provides insights about the mechanisms of the powder-gas interaction in laser powder bed fusion processes.
Study of Droplet Diffusion in Hydrothermal-Assisted Transient Jet Fusion of Ceramics
Authors: Fei Fan , He Li , Kirby Levi , Song Xuan 
Published: September 2020

Abstract
Hydrothermal-assisted transient jet fusion (HTJF) is a powder-based additive manufacturing (AM) method of ceramics, which utilizes a water-mediated hydrothermal mechanism to fuse particles together, eliminating the use of organic binders in forming green bodies and thereby contributing to high green-density parts (&gt;90%) advantageous for fabricating functional materials with high performance. In the HTJF process, a transient solution such as water is selectively deposited into a powder bed in a layer-by-layer fashion followed by a hydrothermal fusion process. Upon the ejection and deposition of a droplet of the transient solution on the surface of the powder bed, the diffusion behavior of the liquid significantly influences the particle fusion and the fabrication accuracy of the HTJF process. Precise control of the liquid diffusion in the powder bed is critical for the fabrication of ceramic structures with both high density and accuracy. In this paper, the dependence of transient solution diffusion on different process parameters (i.e., powder packing density, droplet size, pressure, etc.) in the HTJF process were studied. Both numerical modeling and experimental methods were used to quantify the relationships between processing parameters and diffusion profiles of transient solution droplets (e.g., diffusion width/depth). Optimum processing conditions were identified to mitigate the undesired diffusion of transient solution droplets in the powder bed.
Effect of Dark Chocolate Supplementation on Tissue Oxygenation, Metabolism, and Performance in Trained Cyclists at Altitude
Authors: Shaw Keely , Singh Jyotpal , Sirant Luke , Neary J. Patrick , Chilibeck Philip D. 
Published: September 2020

Dark chocolate (DC) is high in flavonoids and has been shown to increase nitric oxide in the blood. Increased nitric oxide has the potential to improve delivery of oxygen to muscle, especially in hypoxic conditions, such as altitude. Our aim was to assess the impact of DC supplementation on cycling performance at altitude. Twelve healthy, trained cyclists (n = 2 females, n = 10 males; age = 35 [12] years; height = 177 [7] cm; mass = 75.2 [11.0] kg; VO2max = 55 [6] ml·kg−1·min−1) were randomized to supplement with 60 g of DC or placebo twice per day for 14 days in a double-blind crossover study. After the 2 weeks of supplementation, the participants attended a laboratory session in which they consumed 120 g of DC or placebo and then cycled for 90 min at 50% peak power output, followed immediately by a 10-km time trial (TT) at simulated altitude (15% O2). The plasma concentration of blood glucose and lactate were measured before and at 15, 30, 60, and 90 min during the steady-state exercise and post TT, while muscular and prefrontal cortex oxygenation was measured continuously throughout exercise using near-infrared spectroscopy. DC resulted in a higher concentration of blood glucose (5.5 [0.5] vs. 5.3 [0.9] mmol/L) throughout the trial and lower blood lactate concentration following the TT (7.7 [1.92] vs. 10.0 [4.6] mmol/L) compared with the placebo. DC had no effect on the TT performance (19.04 [2.16] vs. 19.21 ± 1.96 min) or oxygenation status in either the prefrontal cortex or muscle. The authors conclude that, although it provided some metabolic benefit, DC is not effective as an ergogenic aid during TT cycling at simulated altitude.
Facilitating the Transition out of Professional Baseball Following Release: A Self-Determination Theory Perspective
Authors: Raabe Johannes , Bass Andrew D. , McHenry Lauren K. , Zakrajsek Rebecca A. 
Published: September 2020

Approximately 90% of players in Minor League Baseball will be released at some point in their career. The purpose of this study was to qualitatively explore the role of individuals’ basic psychological needs during the release from professional baseball and throughout their subsequent transition to a new career. Semistructured interviews were conducted with 12 former Minor League Baseball players. Thematic analysis generated four themes: (a) The release resulted in immediate but temporary basic psychological need thwarting, (b) the “liberating experience” of the release allowed individuals to perceive autonomy in the transition out of affiliated baseball, (c) perceptions of competence served as the foundation for a positive transition to a new career, and (d) meaningful connections fostered individuals’ perception of relatedness in the transition out of affiliated baseball. The findings suggest that need fulfillment might act as a buffer between potential stressors in the transition process and athletes’ cognitive, emotional, and behavioral response.
Intrasession repeatability and intersession reproducibility of peripapillary OCTA vessel parameters in non-glaucomatous and glaucomatous eyes
Authors: Lee Jae Chang , Grisafe Dominic J , Burkemper Bruce , Chang Brenda R , Zhou Xiao , Chu Zhongdi , Fard Ali , Durbin Mary , Wong Brandon J , Song Brian J , Xu Benjamin Y , Wang Ruikang , Richter Grace M 
Published: September 2020

Objective
To compare intrasession repeatability versus intersession reproducibility of the peripapillary vessel parameters using optical microangiography–based optical coherence tomography angiography (OCTA) in non-glaucomatous and glaucomatous eyes.

Methods

In an observational, longitudinal study, peripapillary OCTA scans were collected to evaluate intrasession repeatability and intersession reproducibility using within-eye coefficient of variation (CV
W
) and intraclass correlation coefficient (ICC). Images were quantified using a custom research–oriented quantification software calculating vessel area density (VAD) and flux and a commercially developed, clinic-oriented quantification software (Cirrus 11.0, Carl Zeiss Meditec) calculating perfusion density (PD) and flux index (FI). Effect of signal strength on the reliability of OCTA parameters was also evaluated.

Results

Among 120 non-glaucomatous eyes, intrasession CV
W
were 4.2% for VAD, 5.3% for flux, 1.5% for PD and 2.0% for FI. The intersession CV
W
were 6.5% for VAD, 8.0% for flux, 2.0% for PD and 3.2% for FI. The intrasession ICC ranged from 0.928 to 0.945, and intersession ICC ranged from 0.811 to 0.866. From 118 glaucomatous eyes, intrasession CV
W
was 9.0% for VAD, 10.3% for flux, 1.7% for PD and 2.3% for FI. The intersession CV
W
was 12.1% for VAD, 14.2% for flux, 2.3% for PD and 3.5% for FI. The intrasession ICC ranged from 0.904 to 0.972, and intersession ICC ranged from 0.855 to 0.955. Signal strength was significantly positively associated with OCTA vessel parameters (p<0.0001) for both groups.

Conclusion
Peripapillary OCTA vessel parameters had greater intrasession repeatability compared to intersession reproducibility in both non-glaucomatous and glaucomatous eyes. The built-in commercially developed quantification software demonstrated greater agreement than the custom research–oriented quantification software.
Prospective study of the association between sport-related concussion and brain morphometry (3T-MRI) in collegiate athletes: study from the NCAA-DoD CARE Consortium
Authors: Bobholz Samuel A , Brett Benjamin L , España Lezlie Y , Huber Daniel L , Mayer Andrew R , Harezlak Jaroslaw , Broglio Steven P , McAllister Thomas , McCrea Michael A , Meier Timothy B 
Published: September 2020

ObjectivesTo determine the acute and early long-term associations of sport-related concussion (SRC) and subcortical and cortical structures in collegiate contact sport athletes.MethodsAthletes with a recent SRC (n=99) and matched contact (n=91) and non-contact sport controls (n=95) completed up to four neuroimaging sessions from 24 to 48 hours to 6 months postinjury. Subcortical volumes (amygdala, hippocampus, thalamus and dorsal striatum) and vertex-wise measurements of cortical thickness/volume were computed using FreeSurfer. Linear mixed-effects models examined the acute and longitudinal associations between concussion and structural metrics, controlling for intracranial volume (or mean thickness) and demographic variables (including prior concussions and sport exposure).ResultsThere were significant group-dependent changes in amygdala volumes across visits (p=0.041); this effect was driven by a trend for increased amygdala volume at 6 months relative to subacute visits in contact controls, with no differences in athletes with SRC. No differences were observed in any cortical metric (ie, thickness or volume) for primary or secondary analyses.ConclusionA single SRC had minimal associations with grey matter structure across a 6-month time frame.
Seizure prevalence in children aged up to 3 years: a longitudinal population-based cohort study in Japan
Authors: Nishiyama Masahiro , Yamaguchi Hiroshi , Ishida Yusuke , Tomioka Kazumi , Takeda Hiroki , Nishimura Noriyuki , Nozu Kandai , Mishina Hiroki , Iijima Kazumoto , Nagase Hiroaki 
Published: September 2020

ObjectiveTo investigate the prevalence of seizures/febrile seizures in children up to 3 years of age and examine the effects of gestational age at birth on the risk for febrile seizures.DesignRetrospective longitudinal population-based cohort study.SettingKobe City public health center, Kobe, Japan, from 2010 to 2018.ParticipantsChildren who underwent a medical check-up at 3 years of age.MethodsInformation regarding seizures was collected from the parents of 96 014 children. We identified the occurrence of seizure/febrile seizure in 74 017 children, whose gestational ages at birth were noted. We conducted a multivariate analysis with the parameter, gestational age at birth, to analyse the risk of seizure. We also stratified the samples by sex and birth weight (<2500 g or not) and compared the prevalence of seizure between those with the term and late preterm births.ResultsThe prevalence of seizure was 12.1% (11.8%–12.3%), 13.2% (12.2%–14.4%), 14.6% (12.4%–17.7%) and 15.7% (10.5%–22.8%) in children born at 37–41, 34–36, 28–33 and 22–27 gestational weeks, respectively. The prevalence of febrile seizures was 9.0% (8.8%–9.2%), 10.5% (9.5%–11.5%), 11.8% (9.7%–14.5%) and 11.2% (6.9%–17.7%) in children born at 37–41, 34–36, 28–33 and 22–27 gestational weeks, respectively. Male was an independent risk factor for seizures (OR: 1.15, 95% CI 1.09 to 1.20; absolute risk increase 0.014, 95% CI 0.010 to 0.019) and febrile seizures (OR: 1.21, 95% CI 1.15 to 1.28; absolute risk increase 0.016, 95% CI 0.012 to 0.020), respectively. Late preterm birth was not associated with an increased risk of seizure/febrile seizure.ConclusionsAlthough very preterm birth may increase the risk of seizure/febrile seizure, the risk associated with late preterm birth is considerably small and less than that associated with male.