bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of a non-Newtonian MR fluid flow between parallel plates by developed CFD code for different numerical schemes
Authors: Önen Murat Can , Parlak Zekeriya 
Published: May 2022

Abstract
Magnetorheological (MR) fluids are composed of a solution of micron-sized magnetizable particles dispersed in a carrier fluid, typically oil. Thus, the MR fluids are classified as smart fluids by showing variable apparent viscosity under a precisely controllable external magnetic field. This feature of the MR fluids gave the possibility to use them in the MR dampers to control variational damping forces. In this work, an MR damper on relatively small scales is considered to investigate the MR fluid flow behavior through the piston annuli where the magnetic field exists. This work mainly focuses on the numerical solutions of the flow variables in a magnetically excited non-Newtonian flow medium by comparing analytical results for various Reynolds numbers. The Herschel–Bulkley (HB) viscous model is used for the non-Newtonian characteristic of the MR fluid. For the numerical modeling of the HB viscous model, the regularized approaches are used to avoid numerical errors. However, contrary to the actual HB model, the regularized models can be incapable to give true apparent viscous values at very low shear rates depending on the regularization parameters. Thus, the present study aims to give a better understanding of choosing the optimal regularization parameters for the studied flow conditions. The second part of the study discusses the numerical discretization schemes aiming to present their performances while changing the Reynolds number between 0.002 and 1. In this manner, a Computational Fluid Mechanics (CFD) solver has been developed for two-dimensional geometries which are meshed with structured grids by using six different discretization schemes including two of the most known total variation diminishing (TVD) schemes. For simplicity of the problem, a two-dimensional parallel plates geometry and a constant magnitude of the magnetic field intensity along the piston annuli are assumed. The study also summarizes the CFD technique by evaluating the physical meaning of the flow field variables.
Introspection dynamics: a simple model of counterfactual learning in asymmetric games
Authors: Couto M C , Giaimo S , Hilbe C 
Published: May 2022

Abstract
Social behavior in human and animal populations can be studied as an evolutionary process. Individuals often make decisions between different strategies, and those strategies that yield a fitness advantage tend to spread. Traditionally, much work in evolutionary game theory considers symmetric games: individuals are assumed to have access to the same set of strategies, and they experience the same payoff consequences. As a result, they can learn more profitable strategies by imitation. However, interactions are oftentimes asymmetric. In that case, imitation may be infeasible (because individuals differ in the strategies they are able to use), or it may be undesirable (because individuals differ in their incentives to use a strategy). Here, we consider an alternative learning process which applies to arbitrary asymmetric games, introspection dynamics. According to this dynamics, individuals regularly compare their present strategy to a randomly chosen alternative strategy. If the alternative strategy yields a payoff advantage, it is more likely adopted. In this work, we formalize introspection dynamics for pairwise games. We derive simple and explicit formulas for the abundance of each strategy over time and apply these results to several well-known social dilemmas. In particular, for the volunteer’s timing dilemma, we show that the player with the lowest cooperation cost learns to cooperate without delay.
Numerical solution and mathematical modelling of mass transport from medicated stent
Authors: Ali Akhtar , Hussain Majid , Inc Mustafa , Hussan Muhammad , Rahman Jamshaid Ul 
Published: May 2022

AbstractRestenosis in arteries is a major problem which can be controlled by using medicated stents. The controlled drug transport from medicated stents has a great effect in decreasing restenosis in arteries. Drug is coated on stents to keep away from the re-narrowing of the artery wall. This device has an advantage of a flexible time delivery of a curative drug to the adjoining blood vessel tissues. The aim of this study is to formulate a mathematical model which describe the process of drug transport from arterial wall and medicated stent. For this purpose, a 3D model is investigated to measure the impact of mass transport from drug eluting stent. The blood flow is modelled by dimensionless Navier stokes equations and the concentration of drug is driven by dimensionless’ convection diffusion equation. The effect of diffusive and advective forces are discovered and these forces can be used to control the drug mass transport. Moreover, the effect of dimensionless parameters such as Peclet numberPe,porositykandReon mass transport from medicated stent and tissue layers is investigated. Characteristic Based Split Galerkin (CBSG) technique is applied to solve the dimensionless equations. In the application of stent-based drug delivery, the governing equations in this exploration give the premise of a plan for examining and computing mass transport in medicated stent and artery wall. The numerical results support to offer a good insight into the possible impacts of various parameters.
Study of electron acceleration induced by ultrashort and ultraintense x-ray free electron laser pulse in the presence of uniform axial magnetic field
Authors: Singh Amit Pratap , Gaur Shiv Shankar 
Published: May 2022

Abstract
There is a great interest in the application of ultraintense and ultrashort lasers in the area of accelerator physics. Recent advances in attosecond pulsed lasers have generated a new possibility in the production of high quality and high energy electron beams. The present work investigates the attosecond laser induced electron acceleration in the presence of an external magnetic field. The electron dynamics is studied with the help of linearly and circularly polarized light in vacuum medium. A similar trend in electron trajectory is observed in both polarizations with relatively more energetic electrons in circular polarization. It is found that the external magnetic field plays an important role to confine the electron motion in the laser field and increase the energy of accelerating electrons considerably.
Effect of electron temperature anisotropy on TEM in reversed-field-pinch plasmas
Authors: Yao Y. , Liu T.C. , Liu S.F. , Zhu K.E. , Kong W. , Li J.C. , Dong J.Q. 
Published: May 2022

Abstract
For the first time in the reversed-field-pinch configuration, trapped electron mode (TEM) with anisotropies of electron temperature and its gradient is studied by solving the gyrokinetic integral eigenmode equation. Detailed numerical analyses indicate that TEM is enhanced by the anisotropy with temperature in the direction perpendicular to the magnetic field that is higher than that in the direction parallel to the magnetic field when the latter is kept constant. However, the enhancement is limited, such that TEM is weakened and even stabilized when the anisotropy is higher than a critical value, due to strong Landau damping. In comparison with the isotropic case, the lower Landau damping with the higher parallel electron temperature makes TEM instability easier to excite, which expands the TEM unstable region in the diagram of density and temperature scale lengths. In addition, it is found that the electron temperature gradient in the perpendicular direction offers a stronger driving force on TEM instability than that in the parallel direction. The overall effects of the temperature gradients of electrons and ions, magnetic shear, safety factor and density gradient on TEM in the presence of the anisotropies are presented in detail.
Uncovering the non-equilibrium stationary properties in sparse Boolean networks
Authors: Torrisi Giuseppe , Kühn Reimer , Annibale Alessia 
Published: May 2022

Abstract
Dynamic processes of interacting units on a network are out of equilibrium in general. In the case of a directed tree, the dynamic cavity method provides an efficient tool that characterises the dynamic trajectory of the process for the linear threshold model. However, because of the computational complexity of the method, the analysis has been limited to systems where the largest number of neighbours is small. We devise an efficient implementation of the dynamic cavity method which substantially reduces the computational complexity of the method for systems with discrete couplings. Our approach opens up the possibility to investigate the dynamic properties of networks with fat-tailed degree distribution. We exploit this new implementation to study properties of the non-equilibrium steady-state. We extend the dynamic cavity approach to calculate the pairwise correlations induced by different motifs in the network. Our results suggest that just two basic motifs of the network are able to accurately describe the entire statistics of observed correlations. Finally, we investigate models defined on networks containing bi-directional interactions. We observe that the stationary state associated with networks with symmetric or anti-symmetric interactions is biased towards the active or inactive state respectively, even if independent interaction entries are drawn from a symmetric distribution. This phenomenon, which can be regarded as a form of spontaneous symmetry-breaking, is peculiar to systems formulated in terms of Boolean variables, as opposed to Ising spins.
Top-down design methodology for a 2 ps rms Jitter at 2.56 GHz of an analog PLL based on Ring and LC Tank Oscillators
Authors: Bechetoille E. , Joly B. , Lemaire O. , Laktineh I. , Manen S. , Mathez H. , Russo P. , Vallerand P. , Vandaele R. 
Published: May 2022

Abstract
A top-down methodology is proposed to design
Phase-Locked-Loops (PLL) using behavioural and transistor-level
simulation in two cases: Ring-Oscillator (RO) and LC Tank Oscillator
(LCTO) with the aim to achieve a low-jitter PLL clock generator in
130 nm process. The optimization of these two PLLs is obtained in
three steps. The first one is to design a model in Verilog-A of each
block with its intrinsic jitter parameter. Each block is simulated
alone to verify the nature of its intrinsic jitter: Frequency
Modulation jitter (FM jitter) or Phase Modulation jitter (PM
jitter). The second step is to place each of these blocks in a
global schematic to obtain a full behavioural PLL. In this way, one
can study the PLL operation and check the effect of each block's
jitter on the PLL output. The third step is to use the intrinsic FM
jitter or PM jitter values to simulate at the transistor level of
each block individually and then all of them together. To evaluate
the loop bandwidth and the loop stability of each of the two PLLs, a
linearized PLL is designed using ideal sources. This approach is
important to check the compatibility of each block in terms of
jitter and bandwidth with respect to the target PLL performance. The
optimization results are used to design and produce two
PLLs. Measurements of these two are found to have an absolute time
jitter of the order of 2 ps rms.
Enhanced optical and electrical properties of CeO2NPs/chitosan nanocomposites
Authors: Ahmed Emad M , Alkathiri Ali A 
Published: May 2022

Abstract
Cerium oxide nanoparticles (CeO2NPs) of different ratios (x = 5, 10, 15, and 20 in wt%) are successfully incorporated into chitosan (CS) to synthesize CeO2NPs/CS nanocomposites by solution cast method. FTIR and XRD analysis confirmed the effective incorporation of CeO2NPs into chitosan nanocomposites. TGA and DTG showed that the thermal stability of the as-prepared nanocomposites is improved. The CeO2NPs/CS nanocomposites exhibited enhanced light absorption capacity in the UV-visible range as x increases, owing to the CeO2NPs’ large bandgap. The transmittance of UV decreased for x = 10 and 15 nanocomposites. Light scattering enhanced for x = 5 and 10 nanocomposites, increasing reflectance. Compared to CS (5.3 eV), the optical energy bandgap lowers to 4.94 eV and 5.1 eV, respectively. Impedance spectroscopy research validates the impedance spectroscopy parameters’ dependency on CeO2NPs concentrations. Because of the growth of multiple polarization types, generating interfaces of numerous defects, and space charge polarization, the dielectric constant increases with increasing x (up to x = 15). The dc conductivity (σ
DC) and the frequency exponent (S) are estimated using the universal Josher’s power law and applied to the ac conductivity data (σ
AC). Obviously, (S) decreases with increasing temperature, which refers to the electrical conductivity that follows the hopping mechanism. In addition, according to the CBH model, the Coulomb barrier of charge carriers (Um) is estimated, showing decreasing values as increasing x and recording the lowest value for x = 15 nanocomposites. Nyquist plots (Z″&Z′) indicate one semicircle arc behavior for all samples. As x rises, the radius of semicircular arcs reduces, suggesting that (σ
DC) increases. The enhanced characteristics of CeO2NPs/CS nanocomposites make them suitable for future bio-applications.
Degradation of Yb–Gd–Ti-Si middle entropy silicides in oxidizing atmosphere
Authors: Arai Yutaro , Inoue Ryo 
Published: May 2022

Abstract
Using arc melting, a novel rare-earth silicide, middle entropy Yb–Gd–Ti-Si, was fabricated for high-temperature material applications. The oxidation behavior of the Yb–Gd–Ti-Si was evaluated through oxidation tests conducted at 1200 °C for 1, 2, 4, and 8 h in air. The oxidation rate at 1200 °C was almost the same, regardless of the addition of Ti. The oxidation rate of Yb–Gd–Ti-Si at lower temperatures (600 °C to 900 °C) was lower than that of Yb–Gd–Si. In addition, detailed microstructural observations indicate that the formation of TiO2 and other oxides in the Yb-Ti–O (Yb–Ti–Si–O) phase suppresses the formation of Yb2O3, causing a drastic oxidation at intermediate temperatures (600 °C to 900 °C). These results indicate that the addition of Ti to Yb–Gd–Si is effective at preventing the preferential oxidation of the grain boundaries at 600 °C to 900 °C, which is commonly observed in metal silicides.
Simulations of energetic alpha particle loss in the presence of toroidal field ripple in the CFETR tokamak
Authors: XU Yingfeng , ZHANG Debing , CHEN Jiale , ZHONG Fangchuan 
Published: May 2022

Abstract
Energetic alpha particle losses with the toroidal field ripple and the Coulomb collision in the CFETR tokamak have been simulated by using the orbit-following code GYCAVA for the steady-state and hybrid scenarios. The effects of the outer boundary and the ripple amplitude on alpha particle losses have been investigated. The loss fractions and heat loads of alpha particles in the hybrid scenario are much smaller than those in the steady-state scenario for a significant ripple amplitude. Some alpha particles in the plasma core are lost due to the ripple stochastic transport for a large ripple amplitude parameter. The heat loads with the last closed flux surface boundary are different from those with the wall boundary for the CFETR tokamak, which can be explained by typical alpha particle orbits. Discrete heat load spots have been observed in alpha particle loss simulations, which is due to the ripple well loss. The transition of the lost alpha particle behavior from the ripple stochastic diffusion to the ripple well trapping has been identified in our CFETR simulations. The Coulomb collision effect is responsible for this transition.
Motivation, benefits, and challenges for new photovoltaic material & module developments
Authors: Oreski G , Stein J S , Eder G C , Berger K , Bruckman L , French R , Vedde J , Weiß K A 
Published: May 2022

Abstract
In the last decade and longer, photovoltaic module manufacturers have experienced a rapidly growing market along with a dramatic decrease in module prices. Such cost pressures have resulted in a drive to develop and implement new module designs, which either increase performance and/or lifetime of the modules or decrease the cost to produce them. In this paper, the main motivations and benefits but also challenges for material innovations will be discussed. Many of these innovations include the use of new and novel materials in place of more conventional materials or designs. As a result, modules are being produced and sold without a long-term understanding about the performance and reliability of these new materials. This has led to unexpected new failure mechanisms occurring few years after deployment, such as potential induced degradation or backsheet cracking. None of these failure modes have been detected after the back then common single stress tests. New accelerated test approaches are based on a combination or sequence of multiple stressors that better reflect outdoor conditions. That allows for identification of new degradation modes linked to new module materials or module designs.
Ante-mortem plasma phosphorylated tau (181) predicts Alzheimer’s disease neuropathology and regional tau at autopsy
Authors: Morrison Madeline S , Aparicio Hugo J , Blennow Kaj , Zetterberg Henrik , Ashton Nicholas J , Karikari Thomas K , Tripodis Yorghos , Martin Brett , Palmisano Joseph N , Sugarman Michael A , Frank Brandon , Steinberg Eric G , Turk Katherine W , Budson Andrew E , Au Rhoda , Goldstein Lee E , Jun Gyungah R , Kowall Neil W , Killiany Ronald , Qiu Wei Qiao , Stern Robert A , Mez Jesse , McKee Ann C , Stein Thor D , Alosco Michael L 
Published: May 2022

Abstract
Blood-based biomarkers such as tau phosphorylated at threonine 181 (phosphorylated-tau181) represent an accessible, cost-effective and scalable approach for the in vivo detection of Alzheimer’s disease pathophysiology. Plasma-pathological correlation studies are needed to validate plasma phosphorylated-tau181 as an accurate and reliable biomarker of Alzheimer’s disease neuropathological changes.
This plasma-to-autopsy correlation study included participants from the Boston University Alzheimer’s Disease Research Center who had a plasma sample analysed for phosphorylated-tau181 between 2008 and 2018 and donated their brain for neuropathological examination. Plasma phosphorelated-tau181 was measured with single molecule array technology.
Of 103 participants, 62 (60.2%) had autopsy-confirmed Alzheimer’s disease. Average time between blood draw and death was 5.6 years (standard deviation = 3.1 years). Multivariable analyses showed higher plasma phosphorylated-tau181 concentrations were associated with increased odds for having autopsy-confirmed Alzheimer’s disease [AUC = 0.82, OR = 1.07, 95% CI = 1.03–1.11, P &lt; 0.01; phosphorylated-tau standardized (z-transformed): OR = 2.98, 95% CI = 1.50–5.93, P &lt; 0.01]. Higher plasma phosphorylated-tau181 levels were associated with increased odds for having a higher Braak stage (OR = 1.06, 95% CI = 1.02–1.09, P &lt; 0.01) and more severe phosphorylated-tau across six cortical and subcortical brain regions (ORs = 1.03–1.06, P &lt; 0.05). The association between plasma phosphorylated-tau181 and Alzheimer’s disease was strongest in those who were demented at time of blood draw (OR = 1.25, 95%CI = 1.02–1.53), but an effect existed among the non-demented (OR = 1.05, 95% CI = 1.01–1.10). There was higher discrimination accuracy for Alzheimer’s disease when blood draw occurred in years closer to death; however, higher plasma phosphorylated-tau181 levels were associated with Alzheimer’s disease even when blood draw occurred &gt;5 years from death.
Ante-mortem plasma phosphorylated-tau181 concentrations were associated with Alzheimer’s disease neuropathology and accurately differentiated brain donors with and without autopsy-confirmed Alzheimer’s disease. These findings support plasma phosphorylated-tau181 as a scalable biomarker for the detection of Alzheimer’s disease.
Performance and Kinematic Differences Between Terrestrial and Aquatic Running inAnolis Sagrei
Authors: Cheu Amy Y , Reed Samantha A , Mann Sara D , Bergmann Philip J 
Published: May 2022

AbstractMany animals frequently transition between different media while navigating their heterogeneous environments. These media vary in compliance, moisture content, and other characteristics that affect their physical properties. As a result, animals may need to alter their kinematics to adapt to potential changes in media while maintaining performance during predator escape and foraging. Due to its fluid nature, water is highly compliant, and although usually associated with swimming, water running has evolved in a variety of animals ranging from insects to mammals. While the best studied large water runners are the bipedal basilisk lizards (Basiliscus spp.), other lizards have also been observed to run across the surface of water, namely, Hemidactylus platyurus, a house gecko, and in this study, Anolis sagrei, the brown anole. Unlike the basilisk lizard, the primarily arboreal Anolis sagrei is not adapted for water running. Moreover, water running in A. sagrei, similar to that of the house gecko, was primarily quadrupedal. Here, we tested for performance and kinematic differences between aquatic and terrestrial running and if the variance in performance and kinematic variables differed between the two media. We found no difference in average and maximum velocity between running on land and water. We also found that Anolis sagrei had higher hindlimb stride frequencies, decreased duty factor, and shorter stride lengths on water, as well as more erect postures. Finally, we found that most kinematics did not differ in variance between the two media, but of those that were different, almost all were more variable during terrestrial running. Our findings show that animals may be capable of specialized modes of locomotion, even if they are not obviously adapted for them, and that they may do this by modulating their kinematics to facilitate locomotion through novel environments.
Genomic evaluation and genome-wide association studies for total number of teats in a combined American and Danish Yorkshire pig populations selected in China
Authors: Fang Fang , Li Jielin , Guo Meng , Mei Quanshun , Yu Mei , Liu Huiming , Legarra Andres , Xiang Tao 
Published: May 2022

Abstract
Joint genomic evaluation by combining data recordings and genomic information from different pig herds and populations is of interest for pig breeding companies because the efficiency of genomic selection (GS) could be further improved. In this work, an efficient strategy of joint genomic evaluation combining data from multiple pig populations is investigated. Total teat number (TTN), a trait that is equally recorded on 13,060 American Yorkshire (AY) populations (~14.68 teats) and 10,060 Danish Yorkshire (DY) pigs (~14.29 teats), was used to explore the feasibility and accuracy of GS combining datasets from different populations. We first estimated the genetic correlation (rg) of TTN between AY and DY pig populations (rg = 0.79, se = 0.23). Then we employed the genome-wide association study to identify quantitative trait locus (QTL) regions that are significantly associated with TTN and investigate the genetic architecture of TTN in different populations. Our results suggested that the genomic regions controlling TTN are slightly different in the two Yorkshire populations, where the candidate QTL regions were on SSC 7 and SSC 8 for the AY population and on SSC 7 for the DY population. Finally, we explored an optimal way of genomic prediction for TTN via three different genomic best linear unbiased prediction models and we concluded that when TTN across populations are regarded as different, but correlated, traits in a multitrait model, predictive abilities for both Yorkshire populations improve. As a conclusion, joint genomic evaluation for target traits in multiple pig populations is feasible in practice and more accurate, provided a proper model is used.