bluuebunny/crossref_metadata_2025_split huggingface dataset:
A descriptive angiographic study of the uterine arteries during pregnancy, the postpartum period and CEH/pyometra in bitches
Authors: Mahdipour Maryam , Mogheiseh Asghar , Ahrari‐Khafi Mohammad Saeed 
Published: January 2021

AbstractThe aim of this descriptive study was to monitor the changes in uterine arteries during pregnancy, postpartum period and pyometra in bitches using angiography. Fifteen uteri of mixed breed bitches on days 24, 30, 33, 40, 43, 47, 50 and 56 of pregnancy and weeks 1, 2, 3, 4 and 7–8 of postpartum and two CEH/pyometra bitches were examined after ovariohysterectomy. The results showed that with the onset of normal pregnancy and in about 30 ± 1 days of gestation, anastomoses begin to form between the left and right middle uterine arteries, developing during the next days and continuing until 4 weeks postpartum. On 4th week after parturition, when physiologic changes occur and the uterus returns to non‐pregnant conditions, these anastomoses begin to degenerate, and they completely disappear approximately on the 7th–8th week after parturition. Similarly, in CEH/pyometra bitches, anastomoses were formed between left and right median uterine arteries. These findings can be considered as a part of the physiological changes of the uterus and its vessels during pregnancy and postpartum periods and could affect the results and interpretation of relevant findings.
Defining core competencies in transfusion medicine for resident physicians: A multi‐specialty Delphi consensus study
Authors: Suleiman Leena , Bakhtary Sara , Manuel Solmaz P. 
Published: January 2021

AbstractBackgroundAlthough resident physicians across disciplines are responsible for ordering blood products and managing sequelae of blood product transfusion, no designated set of competencies in transfusion medicine has been established for postgraduate trainees. The primary goal of this study was to determine core transfusion‐related competencies that such residents should possess.Study Design and MethodsA modified Delphi method was used to achieve consensus among a panel of clinical faculty and program leadership in six medical specialties to establish core transfusion‐related competencies for resident physicians. Review of transfusion education literature, relevant clinical responsibilities, and specialty licensing requirements facilitated generation of an initial transfusion medicine topic list and additional topics were considered if suggested by experts. In two Delphi rounds, experts rated the clinical significance of initial topics on a 5‐point Likert scale. Select topics were deemed core competencies if identified as Extremely Important or Moderately Important by at least 75% of panelists to meet a minimum content validity index (CVI) of 0.75 and if topics achieved a minimum content validity ratio (CVR) of 0.5.ResultsNineteen invited clinical experts completed both Delphi rounds with 100% completion across the two rounds. Twenty transfusion medicine topics achieved minimum CVI 0.75 and minimum CVR 0.5. Highest‐ranked topics by level of importance include Red Blood Cell (RBC) Transfusion Indications, Platelet Transfusion Indications, and Pulmonary Reactions.ConclusionsMultispecialty panelists across six medical specialties reached consensus in identification of core transfusion‐related competencies for resident physicians. Such consensus‐driven core competencies may inform the development of transfusion medicine curricula and assessments to improve transfusion safety.
Transversely Stable Extended Kalman Filters for Systems on Manifolds in Euclidean Spaces
Authors: Park Jae-Hyeon , Phogat Karmvir Singh , Kim Whimin , Chang Dong Eui 
Published: January 2021

Abstract
In this article, we devise a variant of the extended Kalman filter that can be generally applied to systems on manifolds with simplicity and low computational cost. We extend a given system on a manifold to an ambient open set in Euclidean space and modify the system such that the extended system is transversely stable on the manifold. Then, we apply the standard extended Kalman filter derived in Euclidean space to the modified dynamics. This method is efficient in terms of computation and accurate in comparison with the standard extended Kalman filter. It has the merit that we can apply various Kalman filters derived in Euclidean space including extended Kalman filters for state estimation for systems defined on manifolds. The proposed method is successfully applied to the rigid body attitude dynamics whose configuration space is the special orthogonal group in three dimensions.
Multimodal Risk-Based Path Planning for Neurosurgical Interventions
Authors: Kunz Christian , Gerst Maximilian , Henrich Pit , Schneider Max , Hlavac Michal , Pala Andrej , Mathis-Ullrich Franziska 
Published: January 2021

AbstractImage-guided neurosurgical interventions are challenging due to the complex anatomy of the brain and the inherent risk of damaging vital structures. This paper presents a neurosurgical planning tool for safe and effective neurosurgical interventions, minimizing the risk through optimized access planning. The strengths of the proposed system are the integration of multiple risk structures combined into a holistic model for fast and intuitive user interaction, and a modular architecture. The tool is intended to support neurosurgeons to quickly determine the most appropriate surgical entry point and trajectory through the brain with minimized risk. The user interface guides a user through the decision-making process and may save planning time of neurosurgical interventions. The navigation tool has been interfaced to the Robot Operating System, which allows the integration into automated workflows and the planning of linear and nonlinear trajectories. Determined risk structures and trajectories can be visualized intuitively as a projection map on the skin or cortical surface. Two risk calculation modes (strict and joint) are offered to the neurosurgeons, depending on the intracranial procedure's type and complexity. A qualitative evaluation with clinical experts shows the practical relevance, while a quantitative performance and functionality analysis proves the robustness and effectiveness of the system.
Reinforcement Learning for Active Noise Control in a Hydraulic System
Authors: Anderson Eric R. , Steward Brian L. 
Published: January 2021

Abstract
Hydraulic pressure ripple in a pump, as a result of converting rotational power to fluid power, continues to be a problem faced when developing hydraulic systems due to the resulting noise generated. In this paper, we present simulation results from leveraging an actor-critic reinforcement learning method as the control method for active noise control in a hydraulic system. The results demonstrate greater than 96%, 81%, and 61% pressure ripple reduction for the first, second, and third harmonics, respectively, in a single operating point test, along with the advantage of feed forward like control for high bandwidth response during dynamic changes in the operating point. It also demonstrates the disadvantage of long convergence times while the controller is effectively learning the optimal control policy. Additionally, this work demonstrates the ancillary benefit of the elimination of the injection of white noise for the purpose of system identification in the current state of the art.
Design, Modeling, and Experimental Characterization of A Valveless Pulsatile Flow Mechanical Circulatory Support Device
Authors: Li Mengtang , Chen Ye , Slepian Marvin J. , Howard Joseph , Thomas Seth , Barth Eric J. 
Published: January 2021

Abstract
Mechanical circulatory support (MCS) devices, i.e., ventricular assist devices (VADs) and total artificial hearts (TAHs), while effective and vital in restoring hemodynamics in patients with circulatory compromise in advanced heart failure, remain limited by significant adverse thrombotic, embolic and bleeding events. Many of these complications relate to chronic exposure, via these devices, to nonpulsatile flow and the high shear stress created by current methods of blood propulsion or use of prosthetic valves. Here we propose a novel noncompressing single sliding vane MCS device to: 1) dramatically reduce pump operating speed thus potentially lowering the shear stress imparted to blood; 2) eliminate utilization of prosthetic valves thus diminishing potential shear stress generations; 3) allow direct flow rate control to generate physically desired blood flow rate include pulsatile flow; and 4) achieve compactness to fit into the majority of patients. The fundamental working principle and governing design equations are introduced first with multiple design and performance objectives presented. A first prototype was fabricated and experimental tests were conducted to validate the model with a 93.10% match between theoretical and experimental flow rate results. After model validation, the proposed MCS was tested to illustrate the ability of pulsatile flow generation. Finally, it was compared with some representative MCS pumps to discuss its potential of improving current MCS design. The presented work offers a novel MCS design and paves the way for next steps in device hemocompatibility testing.
Triphenylamine-Contained Multiporous Polyimide: Its Preparation and Application as Anode for Lithium-Ion Storage
Authors: Su Chang , Sun Man , Guo Pengju , Xu Lihuan 
Published: January 2021

Abstract
The three-dimensional (3D) multiporous structure polyimides were obtained by introducing of the triphenylamine (TPA) unit as linkage in the pyromellitic-based polyimide (N1) and the naphthalene-1,4,5,8-tetracarboxylic-based polyimides (N2), respectively. Then, the functional polyimides were explored as the anode of lithium ion batteries instead of as traditional cathode. As a result, the obtained triphenylamine-based polyimides exhibited a good reversible capacity and remarkably improved rate performance. Especially for the porous N1, it delivered a gradually increased capacity of up to 349 mAh/g during the cycle testing and a rate capacity of 400 mAh/g at an even high current density of 500 mA/g. Significant electrochemical performances for the triphenylamine-contained polyimide could be ascribed to the unique polyimide chemical structure and the constructed 3D multiporous structure with the high surface area (738 m2/g for N1 and 456 m2/g for N2), which benefited to excellent Li+ diffusion kinetics in porous electrode. This makes it promising as anode of rechargeable batteries with the remarkably electrochemical performances.
State of Charge Evaluation of Power Battery Pack Through Multi-Parameter Optimization
Authors: Xu You , Li Jiehao , Xu Wei , Wu Jing , Li Shuli , Wu Qiang 
Published: January 2021

Abstract
The state of charge (SoC) is an important index of the energy output performance of power battery pack. But the SoC value is affected by various factors, namely, ambient temperature, working current, equilibrium potential, and the consistency between batteries in the pack. These factors might dampen the accuracy of the traditional SoC evaluation methods like current–voltage method and Kalman filter. The evaluation accuracy is also influenced by the data drift and rest time to equilibrium potential. Considering the multiple influencing factors of SoC, this paper analyzes the data drift and rest time to equilibrium potential, and builds an approximate model of overpotential for 32650 LiFePO4 battery, based on the time variation constant and the monotonicity of SoC trend. The proposed model was adopted to optimize the evaluation of SoC. To verify its effectiveness, the proposed method was compared with current–voltage method and Kalman filter through experiments. The results show that our method outperformed the contrastive methods in simplicity, relative error (&lt;2.33%), compatibility, and state of health (SoH).
Syngas Characteristics From Catalytic Gasification of Polystyrene and Pinewood in CO2 Atmosphere
Authors: Liu Xuan , Burra Kiran Raj G. , Wang Zhiwei , Li Jinhu , Che Defu , Gupta Ashwani K. 
Published: January 2021

Abstract
Syngas production from catalytic gasification of polystyrene and pinewood in CO2 atmosphere was investigated over Ni-Mg/Al2O3 catalyst in a fixed-bed reactor at 900 °C. A quasi in situ method was adopted for catalytic gasification wherein the catalyst placed downstream of the feedstock in the same reactor was used for enhanced syngas production. The effect of catalyst on evolutionary behavior, cumulative syngas yield, syngas composition, and cold gas efficiency was systematically analyzed. The results showed that addition of catalyst for polystyrene gasification resulted in enhanced yields of 63% H2, 20% CO, 119% CH4, and 85% C2-C3 yields. Enhanced H2 and light hydrocarbon yields were mainly from enhanced cracking of pyrolytic vapors from polystyrene degradation, while the CO yield was attributed to CO2-assisted reforming of benzene derivatives from primary cracking and polycyclic aromatic hydrocarbons (PAHs) from secondary gas phase condensations. The yields of H2, CO, CH4, and C2-C3 from pinewood gasification in the presence of catalyst was also enhanced by 150%, 14%, 39%, and 16%, respectively, indicating that Ni-Mg/Al2O3 catalyst can efficiently enhance syngas production in CO2-assisted gasification. A comparison of syngas composition between non-catalytic and catalytic conditions revealed improved syngas quality in catalytic gasification with increased H2 mole fraction but decreased CO mole fraction. Furthermore, cold gas efficiency enhanced from 44% to 57% in catalytic polystyrene gasification, and from 75% to 94% in catalytic pinewood gasification. The results suggest that catalytic CO2 gasification offers a promising pathway for efficient energy production from wastes plastics and biomass while simultaneously using CO2.
Current-Dependent Dynamics of Bidirectional Self-Folding for Multi-Layer Polymers Using Local Resistive Heating
Authors: Elsisy Moataz , Poska Evan , Abdulhafez Moataz , Bedewy Mostafa 
Published: January 2021

Abstract
The purpose of this paper is to characterize the dynamics and direction of self-folding of pre-strained polystyrene (PSPS) and non-pre-strained styrene (NPS), which results from local shrinkage using a new process of directed self-folding of polymer sheets based on a resistively heated ribbon that is in contact with the sheets. A temperature gradient across the thickness of this shape memory polymer (SMP) sheet induces folding along the line of contact with the heating ribbon. Varying the electric current changes the degree of folding and the extent of local material flow. This method can be used to create practical three-dimensional (3D) structures. Sheets of PSPS and NPS were cut to 10 × 20 mm samples, and their folding angles were plotted with respect to time, as obtained from in situ videography. In addition, the use of polyimide tape (Kapton) was investigated for controlling the direction of self-folding. Results show that folding happens on the opposite side of the sample with respect to the tape, regardless of which side the heating ribbon is on, or whether gravity is opposing the folding direction. The results are quantitatively explained using a viscoelastic finite element model capable of describing bidirectional folds arising from the interplay between viscoelastic relaxation and strain mismatch between polystyrene and polyimide. Given the tunability of fold times and the extent of local material flow, resistive-heat-assisted folding is a promising approach for manufacturing complex 3D lightweight structures by origami engineering.
Corrosion Behavior of an Anti-Icing Coating on an Aluminum Alloy: An Experimental and Numerical Study
Authors: Zhang Wei , Lv Sheng-Li , Lv Yi , Gao Xiaosheng , Srivatsan T. S. 
Published: January 2021

Abstract
In this paper, a coating–substrate interfacial corrosion test method was developed to simulate and study the failure processes occurring at the coating interface as a direct consequence of environment-induced degradation or corrosion. It was found that the corrosion-induced failure rate of the coating–substrate interface upon exposure to an aggressive corrosive medium was high. Microscopic pits tend to appear at the interface of the coating and the substrate. The permeation channel at the coating interface did cause the corrosive medium, primarily the chloride ions, to gradually diffuse from the sides of the sample to the inner surface of the interface thereby enabling the initiation and continued progression of “local” corrosion. The process for failure due essentially to corrosion of the coating was established, while ensuring to include the infiltration phase, the presence of “local” corrosion phases, expansion, if any, due to corrosion, and eventually culminating in failure. Based on the experimental results, a finite element simulation of the “local” corrosion occurring at the coating interface was executed. The results revealed the microscopic pits at the interface to progressively increase the “local” stress concentration on the surface of the substrate but were found to have little influence on overall stress distribution in the coating. It was also found the shape of the etch pit had an effect on failure expansion under the influence of stress. The numerical method can be used to predict structural failure caused by corrosion pits at the interface of the coating–substrate system in an aggressive environment.
Study on Tribological Properties of a New Fe3Al-Based Alloy as an Alternative Material for Scraper Conveyor
Authors: Wang Qingliang , Meng Li , Chen Hui , Zheng Qihao 
Published: January 2021

AbstractThis work reports on the sliding wear properties of Fe3Al-based alloy in conditions of dry sliding and quartz sand abrasion. The wear strengthening mechanism is also analyzed in detail. On this basis, the feasibility of using Fe3Al-based alloy instead of 42CrMo steel to make the wear-resistant scraper components in scraper conveyor is discussed. The results show that the wear mass loss and wear-rate of Fe3Al-based alloy are significantly lower than 42CrMo steel in dry sliding wear and abrasion by quartz sand, which indicates good sliding wear resistance. The wear resistance of Fe3Al-based alloy can be attributed to the grain boundary strengthening caused by the carbide precipates, dislocation fine-grained strengthening, and hard phase strengthening of Al2O3 in the wear surface. Compared with quenched and tempered 40CrMo steel, the lower density of Fe3Al-based alloy can reduce the weight of scraper components by about 15%, and the lower matrix hardness can reduce the wear loss of middle groove and scraper chain. The hardening effect of the worn surface layer can effectively improve the sliding wear resistance of the scraper by about 68%, which is very beneficial to improve the service life and reliability of the scraper conveyor.
The Effect of Pressure on NOx Entitlement and Reaction Timescales in a Premixed Axial Jet-In-Crossflow
Authors: Stiehl Bernhard , Otero Michelle , Genova Tommy , Martin Scott , Ahmed Kareem 
Published: January 2021

Abstract
This paper investigates the pressure dependency of a lean premixed jet injected into a lean vitiated crossflow with an experimentally verified detailed chemistry computational fluid dynamics (CFD) model and 53 species considered. Experimental data were taken in an axially staged combustor with an optically accessible test section, allowing the use of particle image velocimetry (PIV) and CH* chemiluminescence techniques as well as point measurement of species concentration, temperature, and pressure. The experimental data cases at one, three, and five atmospheres were selected to describe the flame stabilization dependency on pressure and gain the required knowledge for an extrapolation to engine condition. Simulated exit nitrogen oxide levels were validated with experimental emission data, and a global emission trend for the NO reduction at elevated pressure and constant turbine inlet temperature level was defined. The nitrogen oxide benefit at elevated operating pressure was justified with the significantly smaller flame surface area: the analysis of the simulated spanwise and top-view profiles showed a relatively short receded core flame with nitrogen oxide production in the center at high pressure relative to a longer and larger shear layer flame at atmospheric condition that produced NO toward the inner and outer side of the flame. Decomposition of the Damköhler number revealed the strong influence of the reaction timescales with higher reaction rates at elevated pressure, along with a moderate influence of the turbulent timescales, showing higher turbulence intensity in the lee-side recirculation zone at lower pressure.
Work of a paediatric bioethics centre during the COVID-19 pandemic first phase
Authors: Brierley Joe , Aylett Sarah , MacNiven Anne , Dittborn Mariana 
Published: January 2021

ObjectivesDecisions with an ethical component have been controversial during the COVID-19 pandemic, whether leaked intensive care unit (ICU)-rationing documents, transfer of people to care-homes to ‘protect the National Health Service’ or the duty to treat patients despite inadequate personal protective equipment. To counter criticism of ethics per se, and to help those planning ethics support we describe the practical work of a children’s hospital bioethics team in supporting children, families and clinicians during this unprecedented period.Design/settingThree phases of activity: (i) preparation: we composed several documents to support/guide hospital teams and, together with colleagues, provided them to regional inpatient, community and hospice settings. We adapted existing mechanisms to combat workforce moral injury; (ii) activity (March–June 2020): was highest in our rapid response service where children/families consider difficult treatment decisions with medical teams. Education provided ‘pandemic webcasts’ on decision-making and broader child-health concerns. Staff support was essential, especially for those deployed to overwhelmed local adult ICUs. Research ascertained young people’s views on the pandemic; (iii) reflection: focussed on (a) research about future re-deployment to adult services and minimisation of moral distress/injury, (b) remote video-conferencing—parents’/participants’ experience/ability to consider complex ethical issues and (c) role of faith/non-faith in society’s recovery and children’s views.Main outcome/conclusionsOur bioethics team’s role during the pandemic included: case reviews via video-conferencing, many involving innovative therapy for severely unwell children with COVID-19/Paediatric-Inflammatory-Multisystem Syndrome-Temporally associated with SARS-CoV-2 together with their parents; processes to protect healthcare staff from moral harm and research/educational activity focused on paediatric-specific ethical arising during the pandemic.