bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparison Between Unstemmed and Stemmed Constrained Condylar Knee Prostheses in Primary Total Knee Arthroplasty: A Propensity Score‐Matched Analysis
Authors: Zhao En‐Ze , Zeng Wei‐Nan , Ding Zi‐Chuan , Liu Zun‐Han , Luo Zhen‐Yu , Zhou Zong‐Ke 
Published: December 2021

ObjectiveTo compare and analyze the clinical outcomes between unstemmed and stemmed constrained condylar knees (CCK) in complex primary total knee arthroplasty (TKA) in terms of implant survivorship, change in outcome evaluations, and complications.MethodsWe reviewed 156 consecutive patients who received primary TKA using PFC®SIGMA®TC3 (TC3) of constrained condylar design between January 2009 and January 2017 at our institution. After removing patients who met exclusion criteria, 25 patients were identified as unstemmed TC3 cases and 81 as stemmed TC3 cases. Propensity score matching was used to select 25 stemmed cases as a control group for the unstemmed group with comparable preoperative conditions including preoperative demographics, preoperative diagnosis, preoperative range of motion, main reason to use TC3, ASA score (American Society of Anesthesiologists), and follow‐up duration. Preoperative and postoperative clinical evaluations including Knee Society Score (KSS), Hospital for Special Surgery (HSS) score, the 12‐Item Short‐Form Health Survey (SF‐12), and the range of motion (ROM) were obtained and compared. The instability, periprosthetic fracture, radiolucent lines, polyethylene wear, and heterotrophic ossification were assessed according to the anteroposterior and lateral radiographs of the knee. The complications and implant survivorship between the two groups were also recorded and compared.Results3After the index surgery, both groups showed substantial improvement in KSS (knee and function), HSS score, SF‐12, and ROM compared with baseline. There was no significant difference in the mean KSS scores (knee and function), HSS score, SF‐12, and ROM between the unstemmed and stemmed group postoperatively. No statistically significant difference was found in the overall complication rate between the two groups. The overall Kaplan–Meier survivorship was 98.0% (95% confidence interval 94.1%–100.0%) at 7 years. No significant difference was found in the survival rate between the unstemmed group (100.0%) and the stemmed group (96.0%) at 7 years (log rank, P = 0.317). The mean duration of follow‐up was 7.0 years for unstemmed group and 7.7 years for stemmed group.ConclusionsIn patients with adequate bone stock receiving complex primary TKA, unstemmed CCK could achieve similar clinical outcomes at mid‐term follow‐up as stemmed CCK.
Ventilation through small‐bore airways in children by implementing active expiration
Authors: de Wolf Michiel , Enk Dietmar , Jagannathan Narasimhan 
Published: December 2021

AbstractManagement of narrowed airways can be challenging, especially in the smallest patients. This educational review focusses on active expiration through small‐bore airways with the Ventrain (Ventinova Medical, Eindhoven, The Netherlands). Manual ventilation with the Ventrain establishes inspiratory and expiratory flow control: By setting an appropriate flow, the volume of gas insufflated over time can be controlled and expiration through a small‐bore airway is expedited by jet‐flow generated suction, coined “expiratory ventilation assistance” (EVA). This overcomes the inherent risks of emergency jet ventilation especially in pediatric airway emergencies. Active expiration by EVA has been clinically introduced to turn a “straw in the airway” into a lifesaver allowing not only for quick and reliable reoxygenation but also adequate ventilation. As well as managing airway emergencies, ventilating through small‐bore airways by applying EVA implements new options for pediatric airway management in elective interventional procedures. Safe application of EVA demands a thorough understanding of the required equipment, the principle and function of the Ventrain, technical prerequisites, clinical safety measures, and, most importantly, appropriate training.
Public health nurses’ encounters with undocumented migrant mothers and children
Authors: Kvamme Eli , Voldner Nanna 
Published: December 2021

AbstractObjectivesUndocumented migrant children (UMC) are often affected by policies and practices that do not take their best interests into account. The aim of this study was to describe how public health nurses (PHNs) experienced challenges and dilemmas in ensuring the best interests of the undocumented migrant child.DesignThis study had a qualitative descriptive design.SampleFocus group interviews and semi‐structured interviews were conducted with seven PHNs in four different child health centers (CHCs).ResultsQualitative content analysis was applied. Three main themes were identified: building trust, ensuring the best interests of the child, and dilemmas and challenges in ensuring the best interests of the child. The study revealed examples of immigration policy being prioritized over the best interests of the child. PHNs experienced frustration when the best interests of the child were not taken into account. Strategies for managing these conflicting demands were identified.ConclusionConflicting demands appeared when national immigration policies collided with fundamental human rights and ethical standards. Rules that exclude certain groups are incompatible with PHNs professional ethics.
Collective autonomy: Why groups fight for power and status
Authors: Kachanoff Frank J. , Gray Kurt , Koestner Richard , Kteily Nour , Wohl Michael J. A. 
Published: December 2021

AbstractPeople experience “collective autonomy restriction” when they believe other groups want to restrict their own group from freely expressing its social identity and determining its behavior. We review emerging research on the negative consequences of collective autonomy restriction for well‐being, as well as its implications for group members' motivation to fight for their place within social hierarchies. We propose that group members desire two resources tied to having a favorable position within the social hierarchy—structural power (i.e., the ability to influence and resist influence from other groups) and status (being positively valued and perceived as moral by others)—because they believe that having power and status are necessary to secure their group's collective autonomy. We hypothesize that group members anticipate that other groups might restrict their group if they lack the structural power to resist outside influences, or if they are perceived as negative or immoral and worthy of restriction. We apply this power and status perspective of collective autonomy restriction to predict (1) when disempowered groups are most likely to fight against (vs. tolerate) their disadvantaged position and (2) when powerful groups are most likely to relinquish power and acknowledge their transgressions (vs. defensively maintain their privileged position).
Curse of friendship: IMF programme, friendship with the United States and foreign direct investment
Authors: Moon Chungshik , Woo Byungwon 
Published: December 2021

AbstractHow do investors respond when a country participates in an International Monetary Fund (IMF) programme? While there exists some optimism in and around the IMF on the catalytic effect of a Fund programme, empirical research on the catalytic finance reports rather diverse findings; contrary to most theoretical research, empirical studies report both positive and negative effects as well as null effects. This paper revisits the question of whether and how an IMF programme catalyses other finances, focusing on the catalytic effect on foreign direct investment (FDI). We modify the core theoretical logic behind the catalytic finance to identify conditions under which an IMF programme is more likely to catalyse FDI: we highlight the credibility of an IMF programme as a key determinant of any positive catalytic effect it may have and reason that politically motivated lending by the IMF can attenuate a programme’s credibility, depressing the catalytic effect. We empirically capture politically motivated lending by looking at the relationship between a borrowing country and the United States and demonstrate that IMF loans to countries closely aligned with the United States are less likely to catalyse FDI than loans to countries that are not aligned with the United States.
Clinical practice for outpatients that are chronically red cell dependent: A survey in the Netherlands
Authors: Tonino Rik P. B. , Schipperus Martin R. , Zwaginga Jaap Jan 
Published: December 2021

AbstractBackground and ObjectivesLimited data are available to guide physicians on how to determine the red blood cell (RBC) transfusion regimen in chronically transfusion‐dependent patients. The lack of clarity on thresholds and targets to be used for transfusion could easily result in either under or over transfusion in these patients. The aim of our survey is to investigate (1) transfusion thresholds; (2) number of RBC units given per transfusion episode; (3) interval between transfusions and (4) patient factors, like decreased cardiac function modulating the former.Materials and MethodsWe sent a web‐based 44‐question survey to members of the Dutch Haematology Association.ResultsFifty physicians responded between June and October 2020 (response rate 30%), well‐distributed between community and academic hospitals. A wide variation in transfusion strategies was reported: Most patients have transfused 1–2 RBC units (range: 0–3 units) every 2–4 weeks (range: 1–12 weeks) with a median threshold of 8.0 g/dl ranging from 6.4 to 9.6 g/dl. Patient‐specific clinical factors that are most frequently reported to influence the transfusion strategy are angina pectoris, cardiac failure and dyspnoea, softer parameters that are of influence are the quality of life and self‐sustainability.ConclusionThe results of this survey indicate a broad variation in RBC transfusion strategies in Dutch patients with chronic transfusion dependency. While the current variation in transfusion strategies may be unavoidable in an individualized approach, randomized trials and better defined usable parameters to evaluate the effect of transfusion strategies are required to reach a consensus on how to determine the transfusion strategy.
A Computationally Efficient Lower Limb Finite Element Musculoskeletal Framework Directly Driven Solely by Inertial Measurement Unit Sensors
Authors: Wang Sentong , Hase Kazunori , Ota Susumu 
Published: December 2021

Abstract
Finite element musculoskeletal (FEMS) approaches using concurrent musculoskeletal (MS) and finite element (FE) models driven by motion data such as marker-based motion trajectory can provide insight into the interactions between the knee joint secondary kinematics, contact mechanics, and muscle forces in subject-specific biomechanical investigations. However, these data-driven FEMS systems have two major disadvantages that make them challenging to apply in clinical environments: they are computationally expensive and they require expensive and inconvenient equipment for data acquisition. In this study, we developed an FEMS model of the lower limb, driven solely by inertial measurement unit (IMU) sensors, that includes the tissue geometries of the intact knee joint and combines muscle modeling and elastic foundation (EF) theory-based contact analysis of a knee into a single framework. The model requires only the angular velocities and accelerations measured by the sensors as input, and the target outputs (knee contact mechanics, secondary kinematics, and muscle forces) are predicted from the convergence results of iterative calculations of muscle force optimization and knee contact mechanics. To evaluate its accuracy, the model was compared with in vivo experimental data during gait. The maximum contact pressure (12.6 MPa) in the rigid body contact analysis occurred on the medial side of the cartilage at the maximum loading response. The proposed computationally efficient framework drastically reduced the computational time (97.5% reduction) in comparison with the conventional deformable FE analysis. The developed framework combines measurement convenience and computational efficiency and shows promise for clinical applications aimed at understanding subject-specific interactions between the knee joint secondary kinematics, contact mechanics, and muscle forces.
Modelling of the Cross Angle and its Impact on Pump Performance
Authors: Rambaks Andris , Schmitz Katharina 
Published: December 2021

Abstract
A secondary swash plate angle, also known as a cross angle, has been used in the past to reduce flow ripple with great success. However, for the past two decades, research in this field has been scarce. In this paper, a pressure controlled 9-piston pump is investigated to determine the effects of the cross angle on commutation, acting forces and torques, as well as volumetric flow rate pulsations. A detailed description of the piston kinematics, the simulation model used, and the subsequent simulation results are presented in this contribution.
Analysis of Pressure Response Characteristics and Influencing Factors of the Automatic Pressure Regulating Valve in Electronic-Controlled Pneumatic Braking System of Commercial Vehicle
Authors: Bao Hanwei , Wang Zaiyu , Wei Xiaoxu , Li Gangyan 
Published: December 2021

Abstract
Automatic pressure regulating valve is the core pressure regulating element in electronic-controlled pneumatic braking system of commercial vehicle, its pressure response characteristics directly affect the real-time and rapid pressure regulation. In this paper, the influence of structural parameters of high-speed solenoid valve on its pressure response characteristics is studied. By analyzing the working principle and structure of high-speed solenoid valve, the mathematical model was established by AMESim. Through the combination of simulation and experiment the correctness of the model is verified. Finally, according to the influence law of key structural parameters in high-speed solenoid valve on the pressure response characteristics of automatic pressure regulating valve, a set of optimized parameters are obtained to realize the improvement and optimization of the pressure response characteristics of the automatic pressure regulating valve.
Machine Learning Prediction of Journal Bearing Pressure Distributions, Considering Elastic Deformation and Cavitation
Authors: Hess Nathan , Shang Lizhi 
Published: December 2021

Abstract
This paper presents a machine learning neural network capable of approximating pressure as the distributive result of elastohydrodynamic effects and discusses results for a journal bearing at steady state. Design of efficient, reliable fluid power pumps and motors requires accurate models of lubricating interfaces; however, most existing simulation models are structured around numerical solutions to the Reynolds equation which involve nested iterative loops, leading to long simulation durations and limiting the ability to use such models in optimization studies. This study presents the development of a machine learning model capable of approximating the pressure solution of the Reynolds equation for given distributive geometric boundary conditions and considering cavitation and elastic deformation at steady-state operating conditions. The architecture selected for this study was an 8-layer U-Net convolutional neural network. A case study of a journal bearing was considered, and a 438-sample training set was generated using an in-house multiphysics simulator. After training, the neural network predicted pressure distributions for test samples with great accuracy, and accurately estimated resultant loads on the journal bearing shaft. Additionally, the neural network showed promise in analyzing geometric inputs outside the space of the training data, approximating the pressure in a grooved journal bearing with reasonable accuracy. These results demonstrate the potential to integrate a machine learning model into fluid power pump and motor simulations for faster performance during evaluation and optimization.
An Analysis of the Effects Causing an Asymmetric Behavior of the Lateral Lubricating Films of External Spur Gear Machines
Authors: Lim Kaeul , Zappaterra Federico , Mukherjee Swarnava , Vacca Andrea 
Published: December 2021

Abstract
The torque efficiency and flow efficiency of positive displacement machines for fluid power applications are determined by the behavior of their internal lubricating interfaces. This aspect has motivated the development of tribological simulation tools for the analysis of these interfaces. The level of details these tools can provide allows explaining some counterintuitive aspects that occur in these interfaces. This paper focuses on a significant example, which is the high asymmetric behavior of the lubricating films occurring in pressure compensated external gear pumps. These units are often designed with a symmetric axial balancing compensation system. Notwithstanding, there are differences between the lateral gaps that can be explained only considering the mutual effects of the pressure development in the film and the material deformation.
To study this problem, this paper utilizes the tool Multics-HYGESim developed by the authors’ research team. Two analyses are performed: the first one imposing axial symmetry in the behavior of the gap, which is the common assumption discussed in literature; the second one (referred to as “full configuration”), which holds the asymmetric behavior of the gap. An experimental set-up is used to validate the modeling assumptions based on the measurements of the drain leakage and volumetric efficiency. The main paper findings are on the uneven distribution of these leakages, which indicates an asymmetric behavior of the gap films in the unit.
A Novel Positive Displacement Axial Piston Machine With Bent Cylinder Sleeves
Authors: Mukherjee Swarnava , Masia Antonio , Bronson Mark , Shang Lizhi , Vacca Andrea 
Published: December 2021

Abstract
In this paper, an investigation of a novel positive displacement axial piston machine using a bent cylinder sleeve configuration is presented. The proposed design eliminates the side moments on the piston/cylinder interface, therefore, reduces the frictional loss and improves the total energy efficiency. A multi-physics elastohydrodynamic lubrication model was used to aid the design of the piston/cylinder and the cylinder block/port block interface. Then, a lumped parameter model was used to optimize the port block geometry. Groove geometry was chosen primarily to reduce flow ripple, tilting moment, and cavitation risk. To improve the housing stiffness, the lumped parameter model was combined with a finite element analysis. This ensured safety for the testing. In the end, steady-state experiments were performed on the prototype based on the ISO4409 normative. The unit’s speed was set to 500 rpm, then increased by 500 rpm until it reached 3000 rpm. The supply pressure was set to 20 bar. The outlet pressure was set to 70 bar at first, then increased by 50 bar until it reached 220 bar. The results show a remarkable volumetric efficiency with a peak of 99.5%. It is however noted that due to some of the issues with the initial iteration of the current design, there is a reduction in mechanical efficiency. The causes and possible future solutions to these issues are discussed in the manuscript.
Dynamical Characteristics of a Hydraulic Soft Actuator With Three Degrees of Freedom
Authors: Xie Qing , Wang Tao , Zhu Shiqiang 
Published: December 2021

Abstract
In recent years, increasing attention and expanding research have been devoted to the study and application of soft actuators. Inherent compliance equips soft actuators with such advantages as incomparable flexibility, good environmental adaptability, safe interaction with the environment, etc. However, the highly nonlinear also bring challenges to modeling of dynamics. This study aims to explore the dynamical characteristics of an underwater hydraulic soft actuator. The actuator has three fiber-reinforced elastomer chambers distributed symmetrically inside. By controlling the pressure in the chambers through a hydraulic power system, the actuator can achieve spatial motion with three degrees of freedom. To describe the relationship between the input pressure combination and the actuator movement, a dynamic model considering the nonlinearity of viscoelastic material is developed based on Lagrangian method and constant curvature hypothesis. A series of experiments are carried out, including single-chamber actuation and multi-chamber actuation. The test results verify the effectiveness and precision of the model. Finally, the effects of the geometrical features on dynamic response are investigated through model-based simulation, which can provide guidance to parameter optimization. The proposed dynamic model can also contribute to behavior analysis, performance prediction, and motion control of the hydraulic soft actuator.
Experimentation on a Hydraulic Energy Storage System for Mid-Size Wind Turbines
Authors: Mohr Eric , Mohanty Biswaranjan , Escobar-Naranjo Daniel , Stelson Kim A. 
Published: December 2021

Abstract
Renewable energy resource investment is crucial to mitigating the effects of climate change. One underrecognized method is improving the performance of mid-sized wind turbines. A hydraulic Energy Storage System (ESS) can be added to a midsized wind turbine transmission to improve system reliability and produce more energy. This hybrid system also offers potential ancillary benefits, such as fault ride-through and strong wind pitch and yaw control. In this paper, results of recent improvements on our previously proposed hybrid system are presented. These improvements include a more realistic accumulator model to improve simulation fidelity and the addition of a hydraulic energy storage system to the power regenerative test platform at the University of Minnesota for experimental validation. Losses of the test platform are characterized and used to improve the quality of the simulation results. Wind samples are used to experimentally validate simulation results. The updated simulation is used to create a refined prediction of the benefits of the hybrid system for a 60 kW turbine.
Improving the Efficiency of a Compact Inline Hydro-Mechanical Transmission (i-HMT) at Lock-Up
Authors: Barkei Johnathan (Hans) , Li Perry Y. 
Published: December 2021

Abstract
A hydro-mechanical transmission (HMT) transmits power both mechanically and hydraulically allowing continuously variable transmission ratios and more efficient transmission than hydrostatic transmission. A conventional HMT tends to be costly and bulky since it has a hydrostatic transmission in parallel with a mechanical transmission. An alternative is a compact inline configuration that utilizes a two-shafted pump that is mechanically and hydraulically connected to a motor. This avoids the need for a planetary gear set while providing the HMT functionality. When the pump/motor displacement is zero, all of the power is transmitted mechanically and the transmission ratio is unity, a condition referred to as lock-up that is expected to be very efficient. Previous research however has shown significant losses at this operating condition in experiments. This is thought to be caused primarily by compressibility losses due to the repeated unnecessary opening and closing of the distributor valves. This paper first models the Hondamatic in simulations to confirm that compressibility losses contribute to the low efficiency at lock-up. Second, the paper proposes a solution to reduce these compressibility losses by means of a second cam mode that closes the distributor valves to prevent flow between the piston and the high and low pressure volumes. The performance of the existing inline HMT and the proposed solution at lock-up are modeled in simulations and compared. The results indicate a 10% increase in efficiency at lock-up.