bluuebunny/crossref_metadata_2025_split huggingface dataset:
Patient characteristics associated with SARS‐CoV‐2 infection in parturients admitted for labour and delivery in Massachusetts during the spring 2020 surge: A prospective cohort study
Authors: Reale Sharon C. , Lumbreras‐Marquez Mario I. , King Chih H. , Burns Stacey L. , Fields Kara G. , Diouf Khady , Goldfarb Ilona T. , Ciaranello Andrea L. , Robinson Julian N. , Gregory Katherine E. , Huybrechts Krista F. , Bateman Brian T. 
Published: January 2021

AbstractBackgroundWhile studies from large cities affected by coronavirus disease 2019 (COVID‐19) have reported on the prevalence of SARS‐CoV‐2 in the context of universal testing during admission for delivery, the patient demographic, social and clinical factors associated with SARS‐CoV‐2 infection in pregnant women are not fully understood.ObjectiveTo evaluate the epidemiological factors associated with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection in women admitted for labour and delivery, in the context of universal screening at four Boston‐area hospitals.MethodsIn this prospective cohort study, we reviewed the health records of all women admitted for labour and delivery at four hospitals from the largest health system in Massachusetts between 19 April 2020 and 27 June 2020. We calculated the risk of SARS‐CoV‐2 infection, including asymptomatic infection. We calculated associations between SARS‐CoV‐2 infection and demographic and clinical characteristics.ResultsA total of 93 patients (3.2%, 95% confidence interval 2.5, 3.8) tested positive for SARS‐CoV‐2 infection on admission for labour and delivery out of 2945 patients included in the analysis; 80 (86.0%) of the patients who tested positive were asymptomatic at the time of testing. Factors associated with SARS‐CoV‐2 infection included the following: younger age, obesity, African American or Hispanic race/ethnicity, residence in heavily affected communities (as measured in cases reported per capita), presence of a household member with known SARS‐CoV‐2 infection, non‐health care essential worker occupation and MassHealth or Medicaid insurance compared to commercial insurance. 93.8% of patients testing positive for SARS‐CoV‐2 on admission had one or more identifiable factors associated with disease acquisition.ConclusionsIn this large sample of deliveries during the height of the surge in infections during the spring of 2020, SARS‐CoV‐2 infection was largely concentrated in patients with distinct demographic characteristics, those largely from disadvantaged communities. Racial disparities seen in pregnancy persist with respect to SARS‐CoV‐2 infection.
Psychological power alters cognitive efficiency
Authors: Lin Enru , Freydefont Laure , Schmid Petra C. 
Published: January 2021

AbstractPower is known to promote cognitive processing in a goal‐directed way. However, it is unknown whether powerful individuals invest more resources when pursuing their goals or whether they invest their resources more efficiently. We examined how experiencing high versus low power affects the efficient investment of cognitive resources using electroencephalography (EEG). Specifically, event‐related desynchronization (ERD) in the upper alpha band (10.5–12.75 Hz) was used to quantify the use of cognitive resources during task completion. Results showed that high‐power participants used fewer neural resources compared to low‐power participants across the whole brain but task performance did not differ between groups. These findings demonstrate that, instead of investing more resources, high‐power participants performed the task with greater cognitive efficiency compared to low‐power participants. Performing tasks efficiently could help powerholders deal with their demanding jobs and responsibilities.
Next generation science classrooms: The development of a questionnaire for examining student experiences in science classrooms
Authors: Campbell Todd , Lee Hyunju , Longhurst Max , McKenna Thomas J. , Coster Daniel , Lundgren Lisa 
Published: January 2021

AbstractIn the United States and internationally, there has been an increased emphasis on the practice turn or a focus on engaging students in more authentic representations of how science is practiced. In this article, we describe the development of a student questionnaire to investigate the extent to which students report being engaged in learning experiences similar to those explicated through the practice turn. We developed a questionnaire that consisted of 35 questions that were separated into four constructs. The questionnaire was determined to be internally consistent, with a high reliability estimate. Confirmatory factor analysis showed item clustering consistent with the research‐derived constructs indicative of a practice turn focus in science classrooms. Furthermore, early evidence from this pilot study is provided to reveal the ability of the questionnaire to detect student experiences that are differentiated at the teacher‐level. Based on the analyses completed, the questionnaire appears to be a needed and useful measure of student‐reported learning experiences that can provide an indication of students’ opportunity to learn in ways aligned to the most recent reforms in science education.
Ethylene increases the cold tolerance of apple via the MdERF1B–MdCIbHLH1 regulatory module
Authors: Wang Yicheng , Jiang Huiyan , Mao Zuolin , Liu Wenjun , Jiang Shenghui , Xu Haifeng , Su Mengyu , Zhang Jing , Wang Nan , Zhang Zongying , Chen Xuesen 
Published: January 2021

SUMMARYCold stress has always been a major abiotic factor affecting the yield and quality of temperate fruit crops. Ethylene plays a critical regulatory role in the cold stress response, but the underlying molecular mechanisms remain elusive. Here, we revealed that ethylene positively modulates apple responses to cold stress. Treatment with 1‐aminocyclopropane‐1‐carboxylate (an ethylene precursor) and aminoethoxyvinylglycine (an ethylene biosynthesis inhibitor) respectively increased and decreased the cold tolerance of apple seedlings. Consistent with the positive effects of ethylene on cold stress responses, a low‐temperature treatment rapidly induced ethylene release and the expression of MdERF1B, which encodes an ethylene signaling activator, in apple seedlings. Overexpression of MdERF1B significantly increased the cold tolerance of apple plant materials (seedlings and calli) and Arabidopsis thaliana seedlings. A quantitative real‐time PCR analysis indicated that MdERF1B upregulates the expression of the cold‐responsive gene MdCBF1 in apple seedlings. Moreover, MdCIbHLH1, which functions upstream of CBF‐dependent pathways, enhanced the binding of MdERF1B to target gene promoters as well as the consequent transcriptional activation. The stability of MdERF1B–MdCIbHLH1 was affected by cold stress and ethylene. Furthermore, MdERF1B interacted with the promoters of two genes critical for ethylene biosynthesis, MdACO1 and MdERF3. The resulting upregulated expression of these genes promoted ethylene production. However, the downregulated MdCIbHLH1 expression in MdERF1B‐overexpressing apple calli significantly inhibited ethylene production. These findings imply that MdERF1B–MdCIbHLH1 is a potential regulatory module that integrates the cold and ethylene signaling pathways in apple.
DGEN Aeropropulsion Research Turbofan Core/Combustor-Noise Measurements—Experiment and Modal Structure at Core-Nozzle Exit1
Authors: Boyle Devin K. , Henderson Brenda S. , Hultgren Lennart S. 
Published: January 2021

Abstract
Data from a recent core/combustor-noise source-diagnostic test (SDT) utilizing a small turbofan engine are analyzed. The campaign continued the exploration begun in a baseline test, but with more extensive acoustic instrumentation. Both tests were aimed at developing a better understanding of propulsion-noise sources and their impact on the farfield noise signature, in order to enable improved turbofan noise-prediction methods and noise-mitigation techniques. Simultaneous high-data-rate acoustic measurements (93 channels in total) were obtained using a circumferential sensor array at the core-nozzle exit in conjunction with sideline and farfield microphone arrays for several relevant engine operational points. Measurements were repeated for different circumferential and sideline array configurations, as well as for redundancy. The unsteady pressure field at the core-nozzle exit is documented in detail. Previous work suggested that the ±1 azimuthal duct mode could be cut on at this location, which would have implications for combustor-noise modeling and prediction. The modal decomposition of the combustor noise at the core-nozzle exit verifies this observation. Select farfield sound pressure level (SPL) spectra are also presented.
Animal Orientation Affects Brain Biomechanical Responses to Blast-Wave Exposure
Authors: Unnikrishnan Ginu , Mao Haojie , Sajja Venkata Siva Sai Sujith , van Albert Stephen , Sundaramurthy Aravind , Rubio Jose E. , Subramaniam Dhananjay Radhakrishnan , Long Joseph , Reifman Jaques 
Published: January 2021

AbstractIn this study, we investigated how animal orientation within a shock tube influences the biomechanical responses of the brain and cerebral vasculature of a rat when exposed to a blast wave. Using three-dimensional finite element (FE) models, we computed the biomechanical responses when the rat was exposed to the same blast-wave overpressure (100 kPa) in a prone (P), vertical (V), or head-only (HO) orientation. We validated our model by comparing the model-predicted and the experimentally measured brain pressures at the lateral ventricle. For all three orientations, the maximum difference between the predicted and measured pressures was 11%. Animal orientation markedly influenced the predicted peak pressure at the anterior position along the midsagittal plane of the brain (P = 187 kPa; V = 119 kPa; and HO = 142 kPa). However, the relative differences in the predicted peak pressure between the orientations decreased at the medial (21%) and posterior (7%) positions. In contrast to the pressure, the peak strain in the prone orientation relative to the other orientations at the anterior, medial, and posterior positions was 40–88% lower. Similarly, at these positions, the cerebral vasculature strain in the prone orientation was lower than the strain in the other orientations. These results show that animal orientation in a shock tube influences the biomechanical responses of the brain and the cerebral vasculature of the rat, strongly suggesting that a direct comparison of changes in brain tissue observed from animals exposed at different orientations can lead to incorrect conclusions.
Complex Energy Networks Optimization: Part I—Development and Validation of a Software for Optimal Load Allocation
Authors: Ancona Maria Alessandra , Bianchi Michele , Branchini Lisa , De Pascale Andrea , Melino Francesco , Peretto Antonio , Rosati Jessica 
Published: January 2021

Abstract
The growing diffusion of the distributed generation systems, due to the European and national legislations which impose the fossil fuel and greenhouse gas emissions reduction and the renewable sources exploitation, have led to an increase in the complexity of the existing energy networks. The main issue of the complex energy grids is their management, which consists in the resolution and optimization of the load allocation problem by minimizing the primary energy consumption and, thus, improving the overall efficiency. In this context, the aim of this paper is to develop and validate a nonlinear algorithm suitable for the resolution of the load allocation problem. In detail, the software combo, which has been developed by the University of Bologna, is based on a nonheuristic algorithm and allows to optimize a complex energy network—characterized by electrical, thermal, cooling and fuel fluxes—by evaluating all the possible combinations of solutions. The objective function of the software consists in the minimization of the total cost of energy production, including not only the variable costs, but also the costs related to the environmental impact of the energy systems. In this paper the mathematical model of the algorithm at the basis of the software combo is presented and described in detail. Furthermore, the software has been validated by its application to a case study and comparing the results with the ones obtained with a previously developed software based on a genetic algorithm (heuristic nonlinear method).
Redesign of Axial Fan Using Viscous Inverse Design Method Based on Boundary Vorticity Flux Diagnosis
Authors: Liu Hui , Jiang Boyan , Wang Wei , Yang XiaoPei , Wang Jun 
Published: January 2021

Abstract
The inverse design method for turbomachinery can directly acquire a blade geometry with specific aerodynamic parameters, such as pressure loading on the blade surfaces. The difference between the inverse design and direct analysis design is that the management of the flow field is controlled by aerodynamic parameters instead of geometric parameters. Although the inverse design has been studied since the 1940s, it is far from being mature enough in comparison with the analysis method. In this work, the inverse problem method is improved by two aspects: the calculation accuracy and the strategy to determine the pressure loading distribution. The application of a high-quality mesh auto-generation and deformation technique to the inverse design is introduced. The no-slip wall boundary conditions, similar to the analysis model, and high-quality mesh, enable the use of an advanced turbulence model in the inverse design. These methods improve the accuracy of the inverse design. The loading distribution in the inverse design is obtained based on the boundary vorticity flux diagnosis. An axial fan is redesigned as an example of the inverse design method. The internal flow loss analysis based on the entropy production theory verifies the effectiveness of the inverse design used in this study.
An Experimental Methodology to Determine Components of Power Losses of a Gearbox
Authors: Dindar A. , Chaudhury K. , Hong I. , Kahraman A. , Wink C. 
Published: January 2021

Abstract
In this study, an experimental methodology is presented to separate various components of the power loss of a gearbox. The methodology relies on two separate measurements. One is designed to measure total power loss of a gearbox housing a single spur gear pair under both loaded and unloaded conditions such that load-independent (spin) and load-dependent (mechanical) components can be separated. With the assumption that gear pair and rolling element bearings constitute the bulk of the gearbox power loss, a second measurement system designed to quantify rolling element bearing losses is proposed. With this setup, spin and mechanical power losses of rolling element bearings used in the gearbox experiments are measured. Combining the sets of gearbox and bearing data, power loss components attributable to the gear pair and rolling element bearings are quantified as a function of speed and torque. The results indicate that all gear and bearing related components are significant and a methodology such as the one proposed in this study is warranted.
Novel Thrust Foil Bearing With Pocket Grooves for Enhanced Static Performance
Authors: LaTray Nguyen , Kim Daejong 
Published: January 2021

Abstract
The integration of foil bearing technology into high-speed oil-free machines has been slow in progress, in part, due to the low load-carrying capacity of the foil thrust bearing. It is crucial this issue is addressed through innovative solutions without overcomplicating the bearing design because simplicity is one of the attractive features of the foil bearing. This work presents novel thrust foil bearing with taper-flat configuration and pocket grooves on the bearing top foil as a secondary pressure boosting mechanism. Parametric study of the pocket dimensions on a rigid bearing reveals that the bearing static performance is the most sensitive to the pocket angular span. Further two-dimensional fluid–structure interaction analyses on foil thrust bearing predict a reduction of power loss by 10% with increased average film thickness. Minimum film thickness also increases when the bearing is lightly loaded but it is reduced 20% at the taper-flat transition area under high loading condition. This issue can be overcome by using stiffer bump foil; however, this is not implemented in this work due to other design constraints. Test results at 90,000 rpm and 140,000 rpm show, by adding the pocket groove pattern on the top foil, the power loss is reduced by 16% compared to the traditional taper-flat configuration.
Acoustic Beamforming Array Design Methods Over Irregular Shaped Areas
Authors: Arcondoulis Elias J. G. , Liu Yu 
Published: January 2021

Abstract
Acoustic beamforming array design methods are typically suited for circular and rectangular areas. A comparison of three array design methods is presented in this paper over irregular shaped areas, including L-shapes and arches. Partial-logarithmic spiral arrays that possess their geometric center either at the origin of the array area or the centroid of the irregular shaped area are compared against randomized array designs based on maximum sidelobe level (MSL) parameters and arrays generated using a recently published array design method named the adaptive array reduction method (AARM). In the AARM, a large array is reduced to a smaller array by seeking the removed microphone that possesses the minimum value of the MSL, the main lobe width (MLW), and a lobe distortion term. The AARM is also tested in two practical cases against a partial spiral array design used at the NASA Langley low-turbulence pressure tunnel and a hypothetical rectangular wall case. In both cases, the AARM showed superior performance to the logarithmic spiral arrays in all cases based on MSL and MLW criteria. Of the three methods compared, the AARM best utilizes the full potential array aperture of an irregular area and therefore produces the best MSL, MLW, and lobe distortion values.
Real-Time Driver Model Parameter Identification: An Algebraic Approach
Authors: Wang Zejiang , Wang Junmin 
Published: January 2021

Abstract
Advanced Driving Assistance System (ADAS) provides warning and automatic control intervention to a human driver for accident avoidance and collision mitigation. To simultaneously minimize the human-machine conflict and enhance human trust in the driving assistance system, ADAS should take personalized driving characteristics into account to support a particular driver in an optimal manner. Typical Personalized Driving Assistance System (PDAS) trains a driver model offline via complicated machine learning algorithms and assumes that the trained driver model maintains reliable until the next model retraining phase. However, even for a specific driver, its driving style can vary substantially due to various factors, e.g., daily mood variation, weather condition, and hardware adaption. To account for the time-varying feature of the driving style, the physics-based driver-model parameter identification has been applied to achieve an authentic PDAS. The commonly employed online driver model parameter identification approach is the Least Square (LS) method. However, LS, leaning on the classical Persistence of Excitation (PE) condition, may have slow estimation convergence. Alternatively, this paper proposes a purely algebraic method for driver model parameter identification. This new approach can achieve almost instantaneous multiple parameter identification. Moreover, by periodically resetting the proposed algebraic identifier, time-varying parameters of the driver model can also be captured online. Simulations demonstrate the excellent performance of the proposed algorithm.
State-Constrained Optimal Solutions for Safe Eco-Approach and Departure at Signalized Intersections
Authors: Han Jihun , Karbowski Dominik , Rousseau Aymeric 
Published: January 2021

Abstract
This paper provides fundamentals of how to energy-efficiently pass through signalized intersections while avoiding any rear-end collisions with leading vehicles. In our previous works [1, 2], analytical solutions with and without second-order pure state constraints imposed by the preceding vehicle were presented; these showed significant energy saving potential for connected and automated vehicles (CAVs) compared to human-driven vehicles. However, these solutions were derived assuming that the desired distance headway policy does not include a speed change over a predictive horizon, and that the preceding vehicle has constant acceleration. We use the desired time headway policy that includes the speed change to define the first-order pure state constraint. We then derive analytical solutions using the direct adjoining method based on Pontryagin’s minimum principle. We also present a novel solver to compute energy-optimal and collision-free state trajectories by accounting for a piecewise constant acceleration of the preceding vehicle without using any numerical optimization methods that require initial guesses. For simple scenarios with one intersection, we analyze how the novel solver allows CAVs to smoothly pass through the signalized intersection and then reach a desired cruising speed. We also use a simulation framework based on high-fidelity powertrain models to validate its effectiveness based on energy savings when driving on real-world urban routes.
Steerable Needle Trajectory Following in the Lung: Torsional Deadband Compensation and Full Pose Estimation With 5DOF Feedback for Needles Passing Through Flexible Endoscopes
Authors: Ertop Tayfun Efe , Emerson Maxwell , Rox Margaret , Granna Josephine , Webster Robert , Maldonado Fabien , Gillaspie Erin , Lester Michael , Kuntz Alan , Rucker Caleb , Fu Mengyu , Hoelscher Janine , Fried Inbar , Alterovitz Ron 
Published: January 2021

Abstract
Bronchoscopic diagnosis and intervention in the lung is a new frontier for steerable needles, where they have the potential to enable minimally invasive, accurate access to small nodules that cannot be reliably accessed today. However, the curved, flexible bronchoscope requires a much longer needle than prior work has considered, with complex interactions between the needle and bronchoscope channel, introducing new challenges in steerable needle control. In particular, friction between the working channel and needle causes torsional windup along the bronchoscope, the effects of which cannot be directly measured at the tip of thin needles embedded with 5 degree-of-freedom magnetic tracking coils. To compensate for these effects, we propose a new torsional deadband-aware Extended Kalman Filter to estimate the full needle tip pose including the axial angle, which defines its steering direction. We use the Kalman Filter estimates with an established sliding mode controller to steer along desired trajectories in lung tissue. We demonstrate that this simple torsional deadband model is sufficient to account for the complex interactions between the needle and endoscope channel for control purposes. We measure mean final targeting error of 1.36 mm in phantom tissue and 1.84 mm in ex-vivo porcine lung, with mean trajectory following error of 1.28 mm and 1.10 mm, respectively.