bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Stability Analysis of a Generic Fan With Distorted Inflow Using Passage-Spectral Method
Authors: Romera David , Corral Roque 
Published: February 2021

Abstract
The dependence of the aerodynamic stability of fan blades with the nodal diameter and amplitude of the inlet perturbations is studied. The analysis is conducted using a block-wise spatial Fourier decomposition of reduced passages to reconstruct the full-annulus solution. The method represents very efficiently the unsteady flow generated by inlet non-uniformities. The explicit spatial Fourier approximation is exploited to characterize the relevance of each nodal diameter of the inlet perturbation in the fan stall process and study the nonlinear stability in a harmonic by harmonic basis. This approximation allows studying the contribution to stall of each circumferential mode separately. The methodology has been assessed for the NASA rotor 67. The maximum amplitude of total pressure distortion at which the compressor becomes unstable and triggers a stall process has been mapped. It has been proven that despite the complexity of a screen-induced total pressure distortion the only relevant parameter for the nonlinear stability of the fan is the most unstable nodal diameter. The equivalence in terms of stability between realistic distortion screens and single harmonic distortions has been assessed. Full-annulus simulations have been conducted to assess the accuracy of the simplified nonlinear stability limit. It is concluded that performing a nonlinear simulation with the proper single harmonic perturbation is enough to assess fan stability. The total pressure error with respect the full annulus simulation including a screen-induced pressure deficit at the intake is below 10%. It is shown that for the NASA rotor 67 running at the nominal speed, the most unstable nodal diameter is the first. This study not only shows a reduction in computational time to assess nonlinear fan stability by a factor of 7 but also creates an efficient methodology for understanding the nonlinear instability of fans due to inlet distortion profiles.
The Influence of Cognitive Dual Tasks on Concussion Balance Test Performance
Authors: Morelli Nathan , Heebner Nicholas R. , DeFeo Courtney J. , Hoch Matthew C. 
Published: February 2021

Objective: To determine the influence of a cognitive dual task on postural sway and balance errors during the Concussion Balance Test (COBALT). Methods: Twenty healthy adults (12 females, eight males; aged 21.95 ± 3.77 years; height = 169.95 ± 9.95 cm; weight = 69.58 ± 15.03 kg) partook in this study and completed single- and dual-task versions of a reduced COBALT. Results: Sway velocity decreased during dual-task head rotations on foam condition (p = .021, ES = −0.57). A greater number of movement errors occurred during dual-task head rotations on firm surface (p = .005, ES = 0.71), visual field flow on firm surface (p = .008, ES = 0.68), and head rotations on foam surface (p < .001, ES = 1.61) compared with single-task conditions. Cognitive performance was preserved throughout different sensory conditions of the COBALT (p = .985). Discussion: Cognitive dual tasks influenced postural control and destabilized movements during conditions requiring advanced sensory integration and reweighting demands. Dual-task versions of the COBALT should be explored as a clinical tool to identify residual deficits past the acute stages of concussion recovery.
Associations of pre-pregnancy impaired fasting glucose and body mass index among pregnant women without pre-existing diabetes with offspring being large for gestational age and preterm birth: a cohort study in China
Authors: Tang Jie , Chen Ruoling , Yu Yizhen , Bao Wei , Tiemeier Henning , Rodney Amanda , Zhu Xinhong , Li Mingzhen , Huang Dongming , Zhao Qingguo 
Published: February 2021

IntroductionAssociations of pre-pregnancy impaired fasting glucose (IFG) and body mass index (BMI) with large for gestational age (LGA) and preterm birth (PTB) have been poorly understood. We aimed to investigate the associations of maternal BMI, separately and together with pre-pregnancy IFG, with LGA and PTB in Chinese population. We also aimed to quantify these associations by maternal age.Research design and methodsThis was a retrospective cohort study of women from the National Free Preconception Health Examination Project with singleton birth from 121 counties/districts in 21 cities of Guangdong Province, China, from January 1, 2013 to December 31, 2017. Women were included if they did not have pre-existing chronic diseases (diabetes, hypertension, etc). Participants were divided into eight groups according to their BMI (underweight (BMI <18.5 kg/m2), normal weight (18.5–23.9 kg/m2), overweight (24.0–27.9 kg/m2), and obesity (≥28.0 kg/m2)) and pre-pregnancy fasting glucose status (normoglycemia (fasting glucose concentration <6.1 mmol/L) and IFG (6.1–7.0 mmol/L)). Adjusted incidence risk ratios (aIRRs) and 95% CIs of LGA, severe LGA, PTB and early PTB were estimated.ResultsWe included 634 030 women. The incidences of LGA, severe LGA, PTB and early PTB for the study population were 7.1%, 2.5%, 5.1% and 1.1%, respectively. Compared with normal weight mothers with normoglycemia, overweight and obese mothers irrespective of IFG had a higher risk of LGA (eg, obesity with IFG aIRR 1.85 (1.60–2.14)) and severe LGA (eg, obesity with IFG 2.19 (1.73–2.79)). The associations of BMI and pre-pregnancy fasting glucose status with LGA were similar found among women of all age groups. Underweight with normoglycemia had 6.0% higher risk of PTB (1.06 (1.03–1.09)) and 8.0% higher risk of early PTB (1.08 (1.02–1.17)), underweight with IFG had 14.0% higher risk of PTB (1.14 (1.02–1.27)), and obese mothers with IFG had 45.0% higher risk of PTB (1.45 (1.18–1.78)). The associations of BMI and pre-pregnancy fasting glucose status with PTB differed by maternal age.ConclusionOverweight and obesity regardless of IFG were associated with an increased risk of LGA, and these associations were similarly observed among mothers of all age groups. Underweight regardless of IFG, and obesity with IFG were associated with an increased risk of PTB, but the associations differed by maternal age. Findings from this study may have implications for risk assessment and counselling before pregnancy.
An examination of contributions of animal- and plant-based dietary patterns on the nutrient quality of diets of adult Canadians
Authors: Fabek Hrvoje , Sanchez-Hernandez Diana , Ahmed Mavra , Marinangeli Christopher P.F. , House James D. , Anderson G. Harvey 
Published: February 2021

Dietary guidance and Canada’s 2019 Food Guide encourage increased consumption of plant-based foods as a source of dietary protein. However, there is an absence of recent data on protein and nutrient intakes and quality of Canadian dietary patterns that might occur with increased plant protein intakes. This study compared food sources and nutrient intakes of Canadian adults within groups of increasing plant protein-containing diets. The CCHS 2015 Public-Use Microdata File of single 24-hour dietary recalls of males and females ≥19 years (n = 6498) or ≥70 years (n = 1482) were examined. Respondents were allocated into 4 groups defined by their protein intake percentage coming from plant-based foods (i.e., group 1: 0–24.9%, group 2: 25–49.9%, group 3: 50–74.9%, group 4: 75–100%). Protein intake in adults averaged 63.3% animal and 36.7% plant protein. Where plant protein contributed >50% protein, higher intakes of carbohydrate, dietary fibre, folate, dietary folate equivalents, iron and magnesium (p < 0.001) but lower intakes of total and saturated fat, protein, vitamin D, vitamin B12, riboflavin and niacin (p < 0.0001) were reported. In contrast, group 1 had higher total and saturated fat, protein, vitamin B12, thiamin, niacin, and zinc, but lower carbohydrate, dietary fibre, and magnesium. Balancing plant- with animal-based protein foods leads to healthier dietary patterns with more favourable nutritional properties when compared with diets based on either high animal or high plant protein content. Novelty: Combinations of animal- and plant-based proteins improve nutrient quality of Canadian diets. The source of protein influences diet quality.
Strange star with Krori–Barua potential in the presence of anisotropy
Authors: Bhar Piyali 
Published: February 2021

In this paper, a well-behaved new model of anisotropic compact star in (3+1)-dimensional spacetime has been investigated in the background of Einstein’s general theory of relativity. The model has been developed by choosing [Formula: see text] component as Krori–Barua (KB) ansatz [Krori and Barua in J. Phys. A, Math. Gen. 8 (1975) 508]. The field equations have been solved by a proper choice of the anisotropy factor which is physically reasonable and well behaved inside the stellar interior. Interior spacetime has been matched smoothly to the exterior Schwarzschild vacuum solution and it has also been depicted graphically. Model is free from all types of singularities and is in static equilibrium under different forces acting on the system. The stability of the model has been tested with the help of various conditions available in literature. The solution is compatible with observed masses and radii of a few compact stars like Vela X-1, 4U [Formula: see text], PSR J[Formula: see text], LMC X [Formula: see text], EXO [Formula: see text].
Mental Models of a Mobile Shoe Rack
Authors: Rueben Matthew , Klow Jeffrey , Duer Madelyn , Zimmerman Eric , Piacentini Jennifer , Browning Madison , Bernieri Frank J. , Grimm Cindy M. , Smart William D. 
Published: February 2021

Most people do not have direct access to knowledge about the inner workings of robots. Instead, they must develop mental models of the robot, a process that is not well understood. This article presents findings from a long-term, in-the-wild, qualitative, hypothesis-generating study of the mental model formation process. The focus was on how (qualitatively) users form mental models of the robot—specifically its perceptual capabilities, rules of behavior, and communication with other humans. Participants of diverse ages had multiple interactions with the robot over six weeks in a non-laboratory setting. The robot’s rules of behavior were changed every two weeks. A novel, non-anthropomorphic robot was created for the study with a realistic use case: storing people’s shoes during a yoga class.
This article reports findings from a case study analysis of 28 interviews conducted over six weeks with six participants. These findings are organized into six topics: (1) variability in the rate at which mental models are updated to be more predictive, (2) types of reasoning and hypothesizing about the robot, (3) borrowing from existing mental models and use of imagination, (4) attributing sensing capabilities where there are no visible sensors, (5) judgments about whether the robot is autonomous or teleoperated, and (6) experimenting with the robot. Specific suggestions for future research are given throughout, culminating in a set of study design recommendations. This work demonstrates the fruitfulness of long-term, in-the-wild studies of human-robot interaction, of which mental model formation is a foundational aspect.
A Non-Intrusive Tool Chain to Optimize MPSoC End-to-End Systems
Authors: France-Pillois Maxime , Martin Jérôme , Rousseau Frédéric 
Published: February 2021

Multi-core systems are now found in many electronic devices. But does current software design fully leverage their capabilities? The complexity of the hardware and software stacks in these platforms requires software optimization with end-to-end knowledge of the system.
To optimize software performance, we must have accurate information about system behavior and time losses. Standard monitoring engines impose tradeoffs on profiling tools, making it impossible to reconcile all the expected requirements: accurate hardware views, fine-grain measurements, speed, and so on. Subsequently, new approaches have to be examined.
In this article, we propose a non-intrusive, accurate tool chain, which can reveal and quantify slowdowns in low-level software mechanisms. Based on emulation, this tool chain extracts behavioral information (time, contention) through hardware side channels, without distorting the software execution flow. This tool consists of two parts. (1) An online acquisition part that dumps hardware platform signals. (2) An offline processing part that consolidates meaningful behavioral information from the dumped data. Using our tool chain, we studied and propose optimizations to MultiProcessor System on Chip (MPSoC) support in the Linux kernel, saving about 60% of the time required for the release phase of the GNU OpenMP synchronization barrier when running on a 64-core MPSoC.
Studies on Affecting Factors of Wheel Slip and Odometry Error on the Performance of Wheeled Mobile Robots – A Review
Authors: Prakash Vidhya 
Published: February 2021

<p>The wheeled mobile robots (WMR) find use for doing a variety of tasks in different types of workspaces. These workspaces are form of ideal natural flat, smooth terrain, unpredictable and irregular nature of these work spaces demanding a design challenges. Typically there work spaces may have pits, undulatory is not flat terrain, obstacles into tasks of the robot. There would result in wheel slippage orodometry error. This tasks a toll in the form of deviation from intended trajectory, navigation, travel time &amp;budgeted energy consumption. These engineering issues can be addressed by proper design of wheel rotation, vibration amplitude of the robot body, travel time modulation differently up to the terrain condition (wet, dry, soft, hard)&amp;wind effect. The wheel slip &amp; odometry error is estimate of computational by design, pay load distribution, speed, wheel diameter, wheel width are the ply able design parameter in the designness scope. The effect of proper selection of the values of there parameters is studied in this review. The paper reviews are analyzing the basic&amp; direct effect of parameters are how to associate with wheel slippage and odometry error and also which is the most affecting factor on the wheeled mobile robots.</p>
Design and Coordination of Cooperative Mobile Robots
Authors: Krid Mohamed 
Published: February 2021

<p>Object transportation is an important task considered in mobile robotics. For many years, it has been performed by single robots, capable to transport payload of moderate size and mass with respect to the robot size and mass. But if the payload gets bigger, the robot fails in the transporting task. For wider or heavier payloads, human operators improve their capacities by working in group. A similar improvement should be expected with a group of mobile robots.</p><p>In this paper, we proposed a new concept of cooperative mobile robots to deal with the problem of long object transportation in unstructured environment whatever the payload length. The proposed C3Bots AT/VLP robot is formed by the association of two or more mono-robots with simple kinematics forming a poly-robot system.</p><p>The paper presents several kinematic schemes and the corresponding obstacle-crossing processes. It deals with the problem of how to maintain stable motion for the poly-robot during obstacle crossing. Changes in the internal configuration of the robot adjust the center of gravity to guarantee stable motion. A specific stability criterion for contact on three wheels is presented. By adjusting the relative poses of the front and rear axles with respect to the payload, it is possible to maximize the stability of the poly-robot and its payload during obstacle crossing.</p>
Optimal Trajectory Planning of Industrial Robots using Geodesic
Authors: Sahu Pradip Kumar 
Published: February 2021

<p>This paper intends to propose an optimal trajectory planning technique using geodesic to achieve smooth and accurate trajectory for industrial robots. Geodesic is a distance minimizing curve between any two points on a Riemannian manifold. A Riemannian metric has been assigned to the workspace by combining its position and orientation space together in order to attain geodesic conditions for desired motion of the end-effector. Previously, trajectory has been planned by considering position and orientation separately. However, practically we cannot plan separately because the manipulator joints are interlinked. Here, trajectory is planned by combining position and orientation together. Cartesian trajectories are shown by joint trajectories in which joint variables are treated as local coordinates of position space and orientation space. Then, the obtained geodesic equations for the workspace are evaluated for initial conditions of trajectory and results are plotted. The effectiveness of the geodesic method validated through numerical computations considering a Kawasaki RS06L robot model. The simulation results confirm the accuracy, smoothness and the optimality of the end-effector motion. </p>
Quantifying the Sex‐Race/Ethnicity‐Specific Burden of Obesity on Incident Diabetes Mellitus in the United States, 2001 to 2016: MESA and NHANES
Authors: Cameron Natalie A. , Petito Lucia C. , McCabe Megan , Allen Norrina B. , O’Brien Matthew J. , Carnethon Mercedes R. , Khan Sadiya S. 
Published: February 2021

Background
Given the increasing prevalence of diabetes mellitus (DM) in the United States, estimating the effects of population‐level increases in obesity on incident DM has substantial implications for public health policy. Therefore, we determined the population attributable fraction, which accounts for the prevalence and excess risk of DM associated with obesity.

Methods and Results
We included non‐Hispanic White, non‐Hispanic Black, and Mexican American participants without DM at baseline from MESA (Multi‐Ethnic Study of Atherosclerosis) with available data on body mass index and key covariates from 2000 to 2017 to calculate unadjusted and adjusted (age, study site, physical activity, diet, income, and education level) hazard ratios (HR) for obesity‐attributable DM. We calculated national age‐adjusted prevalence estimates for obesity using data from NHANES (National Health and Nutrition Examination Survey) in 4 pooled cycles (2001–2016) among adults with similar characteristics to MESA participants. Last, we calculated unadjusted and adjusted population attributable fractions from the race/ethnic and sex‐specific HR and prevalence estimates. Of 4200 MESA participants, the median age was 61 years, 46.8% were men, 53.9% were non‐Hispanic White, 32.9% were non‐Hispanic Black, and 13.3% were Mexican. Among MESA participants, incident DM occurred in 11.6% over a median follow‐up of 9.2 years. The adjusted HR for obesity‐related DM was 2.7 (95% CI, 2.2–3.3). Adjusted population attributable fractions were 0.35 (95% CI, 0.29–0.40) in 2001 to 2004 and 0.41 (95% CI, 0.36–0.46) in 2013 to 2016, and greatest among non‐Hispanic White women.

Conclusions
The contribution of obesity towards DM in the population remains substantial and varies significantly by race/ethnicity and sex, highlighting the need for tailored public health interventions to reduce obesity.

Registration

URL:
https://www.clinicaltrials.gov
; Unique identifiers: NC00005487, NCT00005154.
Statins After Ischemic Stroke in the Oldest
Authors: Lefeber Geert J. , Knol Wilma , Souverein Patrick C. , Bouvy Marcel L. , de Boer Anthonius , Koek Huiberdina L. 
Published: February 2021

Background and Purpose:
Statins are frequently initiated in patients aged 80 years and older after an ischemic stroke, even though evidence on prevention of recurrent cardiovascular disease is scarce. In this study, we seek evidence for statin prescription in the oldest old.

Methods:
We performed a retrospective cohort study in patients aged 65 years and older hospitalized for a first ischemic stroke between 1999 and 2016 without statin prescriptions in the year before hospitalization using the Clinical Practice Research Datalink. The age group 65 to 80 years was included to compare our results to current evidence on statin efficacy. The primary outcome was a composite of recurrent stroke, myocardial infarction, and cardiovascular mortality. The secondary outcome was all-cause mortality. A time-varying Cox model was used to account for statin prescription over time. We compared at least 2 years of statin prescription time with untreated and <2 years of prescription time. Analyses were adjusted for potential confounders. The number needed to treat was calculated based on the adjusted hazard ratios and corrected for deaths during the first 2 years of follow-up.

Results:
Five thousand nine hundred ten patients, aged 65 years and older were included, of whom 3157 were 80 years and older. Two years of statin prescription in patients aged 80 years and older resulted in both a lower risk of the composite end point (adjusted hazard ratio, 0.80 [95% CI, 0.62–1.02]) and all-cause mortality (adjusted hazard ratio, 0.67 [95% CI, 0.57–0.80]). After correction for the mortality of 23.9% of the patients during the first 2 years, the number needed to treat was 64 for the primary outcome during a median follow-up of 3.9 years and 19 for all-cause mortality.

Conclusions:
Statins initiated in patients aged 80 and older, discharged home after hospitalization for an ischemic stroke are associated with a reduction in cardiovascular events.
Circulatory MicroRNAs as Potential Biomarkers for Stroke Risk
Authors: Mens Michelle M.J. , Heshmatollah Alis , Fani Lana , Ikram M. Arfan , Ikram M. Kamran , Ghanbari Mohsen 
Published: February 2021

Background and Purpose:
MicroRNAs (miRNAs) are post-transcriptionally regulators of gene expression that can be released extracellularly upon pathophysiological processes. By complementary binding of target transcripts, miRNAs can modulate the expression of an abundance of genes. Increasing evidence recognize miRNAs as promising biomarkers for complex traits, including cardiovascular disease and stroke. We conducted a longitudinal study to determine the association between circulatory miRNAs and incident stroke in a population-based setting.

Methods:
Next-generation sequencing was used to measure expression levels of 2083 miRNAs in plasma samples, collected between 2002 and 2005, from 1914 stroke-free participants of the Rotterdam Study. Participants were assessed for incident stroke through continuous monitoring of medical records until January 1, 2016. Cox proportional hazards regression models adjusted for age, sex, and vascular risk factors were used to investigate the association between the levels of 591 miRNAs well-expressed in plasma and incident stroke. Furthermore, stroke subtype analysis was performed to assess the link between identified miRNAs and ischemic, hemorrhagic, and unspecified stroke. Subsequently, post hoc analyses were conducted to gain insight into the association between putative target genes of miRNAs and stroke.

Results:

Of 1914 participants (mean age 71.5 years ±7.6; 57.7% women), 138 were diagnosed with incident stroke during a mean follow-up of 9.7±3.2 years. After adjusting for potential confounders, we found plasma levels of 3 miRNAs to be associated with incident stroke (false discovery rate-adjusted
P
<0.05). These include miR-6124 (hazard ratio, 1.66 [95% CI, 1.31–2.09]), miR-5196-5p (hazard ratio, 1.90 [95% CI, 1.39–2.61]), and miR-4292 (hazard ratio, 2.65 [95% CI, 1.62–4.34]). In silico analysis of the putative target genes of these miRNAs showed associations of variants in several target genes with stroke.

Conclusions:
This study indicates that plasma levels of 3 miRNAs are associated with the risk of stroke, proposing them as potential biomarkers for early detection of the disease.