bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal Model of an Omnimagnet for Performance Assessment and Temperature Control
Authors: Esmailie Fateme , Cavilla Matthew S. , Abbott Jake J. , Ameel Tim A. 
Published: January 2021

Abstract
An Omnimagnet is an electromagnetic device that enables remote magnetic manipulation of devices such as medical implants and microrobots. It is composed of three orthogonal nested solenoids with a ferromagnetic core at the center. Electrical current within the solenoids leads to undesired temperature increase within the Omnimagnet. If the temperature exceeds the melting point of the wire insulation, device failure may occur. Thus, a study of heat transfer within an Omnimagnet is a necessity, particularly to maximize the performance of the device. A transient heat transfer model that incorporates all three heat transfer modes is proposed and experimentally validated with an average normalized root-mean-square error of less than 4% (data normalized by temperature in degree celsius). The transient model is not computationally expensive and is applicable to Omnimagnets with different structures. The code is applied to calculate the maximum safe operational time at a fixed input current or the maximum safe input current for a fixed time interval. The maximum safe operational time and maximum safe input current depend on size and structure of the Omnimagnet and the lowest critical temperature of all the Omnimagnet materials. A parametric study shows that increasing convective heat transfer during cooling, and during heating with low input currents, is an effective method to increase the maximum operational time of the Omnimagnet. The thermal model is also presented in a state-space equation format that can be used in a real-time Kalman filter current controller to avoid device failure due to excessive heating.
Coupled Computation Fluid Dynamics Models for Air Flow and Thermal Analysis of Marine Engine Room
Authors: George Jithin A. , Saha Sandip K. 
Published: January 2021

Abstract
Thermal management of machinery spaces of marine vessels using a heating ventilation and air conditioning (HVAC) system is needed to maintain the temperature within the tolerable limit for efficient combustion in internal combustion engines and proper functioning of on-board electronic devices by removing high heat generations from in-house auxiliary systems. This study presents a numerical methodology using coupled simple and detailed computational fluid dynamics (CFD) models of air passages and engine components. The developed method is found to have a good agreement with the experimental results. Further, different layouts of vents and heat-generating components in the engine room are analyzed to obtain air flow and temperature distributions. It is found that the locations of vents and heat generating components have a significant effect on the maximum temperature distribution in the engine room.
Modeling and Prediction of Rigid Body Motion With Planar Non-Convex Contact
Authors: Xie Jiayin , Chakraborty Nilanjan 
Published: January 2021

Abstract
We present a principled method for motion prediction via dynamic simulation for rigid bodies in intermittent contact with each other where the contact region is a planar non-convex contact patch. Such methods are useful in planning and controlling for robotic manipulation. The planar non-convex contact patch can either be a topologically connected set or a disconnected set. Most works in rigid body dynamic simulation assume that the contact between objects is a point contact, which may not be valid in many applications. In this paper, using the convex hull of the contact patch, we build on our recent work on simulating rigid bodies with convex contact patches for simulating motion of objects with planar non-convex contact patches. We formulate a discrete-time mixed complementarity problem to solve the contact detection and integration of the equations of motion simultaneously. We solve for the equivalent contact point (ECP) and contact impulse of each contact patch simultaneously along with the state, i.e., configuration and velocity of the objects. We prove that although we are representing a patch contact by an equivalent point, our model for enforcing non-penetration constraints ensures that there is no artificial penetration between the contacting rigid bodies. We provide empirical evidence to show that our method can seamlessly capture transition among different contact modes like patch contact, multiple or single point contact.
Embedded Actuation for Shape-Adaptive Origami
Authors: Grey Steven W. , Scarpa Fabrizio , Schenk Mark 
Published: January 2021

Abstract
Origami-inspired approaches to deployable or morphing structures have received significant interest. For such applications, the shape of the origami structure must be actively controlled. We propose a distributed network of embedded actuators which open/close individual folds and present a methodology for selecting the positions of these actuators. The deformed shape of the origami structure is tracked throughout its actuation using local curvatures derived from discrete differential geometry. A Genetic Algorithm (GA) is used to select an actuation configuration, which minimizes the number of actuators or input energy required to achieve a target shape. The methodology is applied to both a deployed and twisted Miura-ori sheet. The results show that designing a rigidly foldable pattern to achieve shape-adaptivity does not always minimize the number of actuators or input energy required to reach the target geometry.
Confidence-Based Design Optimization for a More Conservative Optimum Under Surrogate Model Uncertainty Caused by Gaussian Process
Authors: Jung Yongsu , Kang Kyeonghwan , Cho Hyunkyoo , Lee Ikjin 
Published: January 2021

Abstract
Even though many efforts have been devoted to effective strategies to build accurate surrogate models, surrogate model uncertainty is inevitable due to a limited number of available simulation samples. Therefore, the surrogate model uncertainty, one of the epistemic uncertainties in reliability-based design optimization (RBDO), has to be considered during the design process to prevent unexpected failure of a system that stems from an inaccurate surrogate model. However, there have been limited attempts to obtain a reliable optimum taking into account the surrogate model uncertainty due to its complexity and computational burden. Thus, this paper proposes a confidence-based design optimization (CBDO) under surrogate model uncertainty to find a conservative optimum despite an insufficient number of simulation samples. To compensate the surrogate model uncertainty in reliability analysis, the confidence of reliability is brought to describe the uncertainty of reliability. The proposed method employs the Gaussian process modeling to explicitly quantify the uncertainty of a surrogate model. Thus, metamodel-based importance sampling and expansion optimal linear estimation are exploited to reduce the computational burden on confidence estimation. In addition, stochastic sensitivity analysis of the confidence is developed for CBDO, which is formulated to find a conservative optimum than an RBDO optimum at a specific confidence level. Numerical examples using mathematical functions and finite element analysis show that the proposed confidence analysis and CBDO can prevent overestimation of reliability caused by an inaccurate surrogate model.
A Digital Twin-Driven Method for Product Performance Evaluation Based on Intelligent Psycho-Physiological Analysis
Authors: Feng Yixiong , Li Mingdong , Lou Shanhe , Zheng Hao , Gao Yicong , Tan Jianrong 
Published: January 2021

Abstract
Digital twin, a new emerging and fast-growing technology which is one of the most promising technologies for smart design and manufacturing, has attracted much attention worldwide recently. With the application of digital twin, product performance evaluation has entered the data-driven era. However, traditional methods for evaluation mainly place emphasis on structure analysis in the stage of manufacturing and service in digital twin. They cannot synthesize multi-source information and take the high-level emotional response into consideration in the design stage. To overcome these disadvantages, a digital twin-driven method is proposed evaluating product design schemes in this study. It enables the acquisition of electroencephalogram (EEG) data, physical data, and emotional feedback. Human factors are systematically considered in the evaluation process to establish the information association between EEG and performance levels. Moreover, intelligent psycho-physiological analysis that incorporates EEG into the fuzzy comprehensive evaluation (FCE) and machine learning methods is adopted within the proposed method. It synthesizes human factors such as psychological requirements, subjective and objective assessment indicators to realize a novel machine learning-based EEG analysis. Taking advantage of the binary particle swarm optimization (BPSO) improved Riemannian manifold mapping, Riemann geometry (RG) features are extracted and selected from EEG signals. Differences of implicit psychological states while using the product produced by different design schemes can be more easily detected and classified. A case study of high-speed elevator is conducted to verify the feasibility and effectiveness of the proposed method. The accuracy of EEG classification for performance evaluation reaches 92%.
Exercise-Induced Salivary Hormone Responses to High-Intensity, Self-Paced Running
Authors: Leal Diogo V. , Taylor Lee , Hough John 
Published: January 2021

Purpose:Physical overexertion can lead to detrimental overreaching states without sufficient recovery, which may be identifiable by blunted exercise-induced cortisol and testosterone responses. A running test (RPETP) elicits reproducible plasma cortisol and testosterone elevations (in a healthy state) and may detect blunted hormonal responses in overreached athletes. This current study determined the salivary cortisol and testosterone responses reproducibility to the RPETP, to provide greater practical validity using saliva compared with the previously utilized blood sampling. Second, the relationship between the salivary and plasma responses was assessed.Methods:A total of 23 active, healthy males completed the RPETPon 3 occasions. Saliva (N = 23) and plasma (N = 13) were collected preexercise, postexercise, and 30 minutes postexercise.Results:Salivary cortisol did not elevate in any RPETPtrial, and reduced concentrations occurred 30 minutes postexercise (P = .029,η2 = .287); trial differences were observed (P < .001,η2 = .463). The RPETPelevated (P < .001,η2 = .593) salivary testosterone with no effect of trial (P = .789,η2 = .022). Intraindividual variability was 25% in cortisol and 17% in testosterone. “Fair” intraclass coefficients of .46 (cortisol) and .40 (testosterone) were found. Salivary and plasma cortisol positively correlated (R = .581,P = .037) yet did not for testosterone (R = .345,P = .248).Conclusions:The reproducibility of salivary testosterone response to the RPETPis evident and supports its use as a potential tool, subject to further confirmatory work, to detect hormonal dysfunction during overreaching. Salivary cortisol responds inconsistently in a somewhat individualized manner to the RPETP.
Fingerprinting sand from Asian rivers to the deep central South China Sea since the Late Miocene
Authors: Cao Licheng , Jiang Tao , He Jingke 
Published: January 2021

Abstract
The complex sedimentary processes from source to sink lead to a substantial fractionation of sediment size and composition. Relatively coarse-grained, continent-derived detritus is rarely transported and deposited in the deep ocean, and the terminus of this sediment routing system is poorly understood. Sandy turbidite deposits within the Upper Miocene–Pleistocene strata drilled in the deep central South China Sea during the International Ocean Discovery Program (IODP) Expedition 349 provide valuable samples for evaluating the evolution of sediment contributions from different Asian landmasses. This study reconstructs this ancient source-to-sink system based on an integration of heavy mineral and detrital zircon analyses (including U-Pb age, trace element, grain size and shape), obtained from IODP sites U1431 and U1432, as well as a zircon age-based mixture modeling of well-defined provenance end-members. The results show several provenance shifts that correspond to more complex and dynamic source-to-sink scenarios than previously envisaged. Certain source areas, like East Vietnam, present a different provenance signature than that of today. Multiple provenances have been mixed and diluted during sediment transport, exhibiting a large regional variability. We interpret that siliciclastic turbidite deposits in the central South China Sea were mainly derived from East Vietnam during the early Late Miocene and Pliocene, and the Pearl River Basin during the late Late Miocene and Pleistocene. Additional, but less significant, contributions from the Red and Mekong river basins and coastal Southeast China are also observed.
Associations between family presence and neonatal intubation outcomes: a report from the National Emergency Airway Registry for Neonates: NEAR4NEOS
Authors: Brei Brianna K , Sawyer Taylor , Umoren Rachel , Gray Megan M , Krick Jeanne , Foglia Elizabeth E , Ades Anne , Glass Kristen , Kim Jae H , Singh Neetu , Jung Philipp , Johnston Lindsay , Moussa Ahmed , Napolitano Natalie , Barry James , Zenge Jeanne , Quek Binhuey , DeMeo Stephen D , Shults Justine , Unrau Jennifer , Nadkarni Vinay , Nishisaki Akira 
Published: January 2021

ObjectiveDescribe the current practice of family presence during neonatal tracheal intubations (TIs) across neonatal intensive care units (NICUs) and examine the association with outcomes.DesignRetrospective analysis of TIs performed in NICUs participating in the National Emergency Airway Registry for Neonates (NEAR4NEOS).SettingThirteen academic NICUs.PatientsInfants undergoing TI between October 2014 and December 2017.Main outcome measuresAssociation of family presence with TI processes and outcomes including first attempt success (primary outcome), success within two attempts, adverse TI-associated events (TIAEs) and severe oxygen desaturation ≥20% from baseline.ResultsOf the 2570 TIs, 242 (9.4%) had family presence, which varied by site (median 3.6%, range 0%–33%; p<0.01). Family member was more often present for older infants and those with chronic respiratory failure. Fewer TIs were performed by residents when family was present (FP 10% vs no FP 18%, p=0.041). Among TIs with family presence versus without family presence, the first attempt success rate was 55% vs 49% (p=0.062), success within two attempts was 74% vs 66% (p=0.014), adverse TIAEs were 18% vs 20% (p=0.62) and severe oxygen desaturation was 49% vs 52%, (p=0.40). In multivariate analyses, there was no independent association between family presence and intubation success, adverse TIAEs or severe oxygen desaturation.ConclusionFamily are present in less than 10% of TIs, with variation across NICUs. Even after controlling for important patient, provider and site factors, there were no significant associations between family presence and intubation success, adverse TIAEs or severe oxygen desaturation.
Neurodevelopmental outcomes following neonatal late-onset sepsis and blood culture-negative conditions
Authors: Mukhopadhyay Sagori , Puopolo Karen M , Hansen Nellie I , Lorch Scott A , DeMauro Sara B , Greenberg Rachel G , Cotten C Michael , Sanchez Pablo J , Bell Edward F , Eichenwald Eric C , Stoll Barbara J 
Published: January 2021

ObjectiveDetermine risk of death or neurodevelopmental impairment (NDI) in infants with late-onset sepsis (LOS) versus late-onset, antibiotic-treated, blood culture-negative conditions (LOCNC).DesignRetrospective cohort study.Setting24 neonatal centres.PatientsInfants born 1/1/2006–31/12/2014, at 22–26 weeks gestation, with birth weight 401–1000 g and surviving >7 days were included. Infants with early-onset sepsis, necrotising enterocolitis, intestinal perforation or both LOS and LOCNC were excluded.ExposuresLOS and LOCNC were defined as antibiotic administration for ≥5 days with and without a positive blood/cerebrospinal fluid culture, respectively. Infants with these diagnoses were also compared with infants with neither condition.OutcomesDeath or NDI was assessed at 18–26 months corrected age follow-up. Modified Poisson regression models were used to estimate relative risks adjusting for covariates occurring ≤7 days of age.ResultsOf 7354 eligible infants, 3940 met inclusion criteria: 786 (20%) with LOS, 1601 (41%) with LOCNC and 1553 (39%) with neither. Infants with LOS had higher adjusted relative risk (95% CI) for death/NDI (1.14 (1.05 to 1.25)) and death before follow-up (1.71 (1.44 to 2.03)) than those with LOCNC. Among survivors, risk for NDI did not differ between the two groups (0.99 (0.86 to 1.13)) but was higher for LOCNC infants (1.17 (1.04 to 1.31)) compared with unaffected infants.ConclusionsInfants with LOS had higher risk of death, but not NDI, compared with infants with LOCNC. Surviving infants with LOCNC had higher risk of NDI compared with unaffected infants. Improving outcomes for infants with LOCNC requires study of the underlying conditions and the potential impact of antibiotic exposure.
NeoBeat offers rapid newborn heart rate assessment
Authors: Bush Jessica Brittany , Cooley Victoria , Perlman Jeffrey , Chang Catherine 
Published: January 2021

BackgroundHeart rate (HR) is used to guide interventions during delivery room (DR) neonatal resuscitation. Dry electrode ECG (NeoBeat) may detect HR more rapidly than pulse oximetry (PO) and portable ECG, but real-time comparisons of these devices are lacking.Design/methodsPO, ECG and NeoBeat were placed sequentially on newborns in the DR. Time for device placement and time to accurate HR acquisition were noted.ResultsDR resuscitations of 28 preterm/term infants were observed. The NeoBeat was placed faster (ie, 3 s) than PO (20 s, p=<0.0001) and ECG (16 s, p=<0.0001). Total time from initiation of device placement to HR acquisition was fastest with NeoBeat (13 s) versus ECG (42 s, p<0.0001) and PO (105 s, p<0.0001) (duration values=median).ConclusionsThese observations in a small cohort of relatively well neonates demonstrate that the NeoBeat is significantly faster to place and consistently acquires HR faster than PO and ECG.
Effect of tocilizumab on clinical outcomes at 15 days in patients with severe or critical coronavirus disease 2019: randomised controlled trial
Authors: Veiga Viviane C , Prats João A G G , Farias Danielle L C , Rosa Regis G , Dourado Leticia K , Zampieri Fernando G , Machado Flávia R , Lopes Renato D , Berwanger Otavio , Azevedo Luciano C P , Avezum Álvaro , Lisboa Thiago C , Rojas Salomón S O , Coelho Juliana C , Leite Rodrigo T , Carvalho Júlio C , Andrade Luis E C , Sandes Alex F , Pintão Maria C T , Castro Claudio G , Santos Sueli V , de Almeida Thiago M L , Costa André N , Gebara Otávio C E , de Freitas Flávio G Rezende , Pacheco Eduardo S , Machado David J B , Martin Josiane , Conceição Fábio G , Siqueira Suellen R R , Damiani Lucas P , Ishihara Luciana M , Schneider Daniel , de Souza Denise , Cavalcanti Alexandre B , Scheinberg Phillip 
Published: January 2021

Abstract

Objective
To determine whether tocilizumab improves clinical outcomes for patients with severe or critical coronavirus disease 2019 (covid-19).

Design
Randomised, open label trial.

Setting
Nine hospitals in Brazil, 8 May to 17 July 2020.

Participants
Adults with confirmed covid-19 who were receiving supplemental oxygen or mechanical ventilation and had abnormal levels of at least two serum biomarkers (C reactive protein, D dimer, lactate dehydrogenase, or ferritin). The data monitoring committee recommended stopping the trial early, after 129 patients had been enrolled, because of an increased number of deaths at 15 days in the tocilizumab group.

Interventions
Tocilizumab (single intravenous infusion of 8 mg/kg) plus standard care (n=65) versus standard care alone (n=64).

Main outcome measure
The primary outcome, clinical status measured at 15 days using a seven level ordinal scale, was analysed as a composite of death or mechanical ventilation because the assumption of odds proportionality was not met.

Results
A total of 129 patients were enrolled (mean age 57 (SD 14) years; 68% men) and all completed follow-up. All patients in the tocilizumab group and two in the standard care group received tocilizumab. 18 of 65 (28%) patients in the tocilizumab group and 13 of 64 (20%) in the standard care group were receiving mechanical ventilation or died at day 15 (odds ratio 1.54, 95% confidence interval 0.66 to 3.66; P=0.32). Death at 15 days occurred in 11 (17%) patients in the tocilizumab group compared with 2 (3%) in the standard care group (odds ratio 6.42, 95% confidence interval 1.59 to 43.2). Adverse events were reported in 29 of 67 (43%) patients who received tocilizumab and 21 of 62 (34%) who did not receive tocilizumab.

Conclusions
In patients with severe or critical covid-19, tocilizumab plus standard care was not superior to standard care alone in improving clinical outcomes at 15 days, and it might increase mortality.

Trial registration

ClinicalTrials.gov
NCT04403685
.
Estimating the burden of cardiovascular risk in community dwellers over 40 years old in South Africa, Kenya, Burkina Faso and Ghana
Authors: Wagner Ryan G , Crowther Nigel J , Micklesfield Lisa K , Boua Palwende Romauld , Nonterah Engelbert A , Mashinya Felistas , Mohamed Shukri F , Asiki Gershim , Tollman Stephen , Ramsay Michèle , Davies Justine I 
Published: January 2021

IntroductionCardiovascular disease (CVD) risk factors are increasing in sub-Saharan Africa. The impact of these risk factors on future CVD outcomes and burden is poorly understood. We examined the magnitude of modifiable risk factors, estimated future CVD risk and compared results between three commonly used 10-year CVD risk factor algorithms and their variants in four African countries.MethodsIn the Africa-Wits-INDEPTH partnership for Genomic studies (the AWI-Gen Study), 10 349 randomly sampled individuals aged 40–60 years from six sites participated in a survey, with blood pressure, blood glucose and lipid levels measured. Using these data, 10-year CVD risk estimates using Framingham, Globorisk and WHO-CVD and their office-based variants were generated. Differences in future CVD risk and results by algorithm are described using kappa and coefficients to examine agreement and correlations, respectively.ResultsThe 10-year CVD risk across all participants in all sites varied from 2.6% (95% CI: 1.6% to 4.1%) using the WHO-CVD lab algorithm to 6.5% (95% CI: 3.7% to 11.4%) using the Framingham office algorithm, with substantial differences in risk between sites. The highest risk was in South African settings (in urban Soweto: 8.9% (IQR: 5.3–15.3)). Agreement between algorithms was low to moderate (kappa from 0.03 to 0.55) and correlations ranged between 0.28 and 0.70. Depending on the algorithm used, those at high risk (defined as risk of 10-year CVD event >20%) who were under treatment for a modifiable risk factor ranged from 19.2% to 33.9%, with substantial variation by both sex and site.ConclusionThe African sites in this study are at different stages of an ongoing epidemiological transition as evidenced by both risk factor levels and estimated 10-year CVD risk. There is low correlation and disparate levels of population risk, predicted by different risk algorithms, within sites. Validating existing risk algorithms or designing context-specific 10-year CVD risk algorithms is essential for accurately defining population risk and targeting national policies and individual CVD treatment on the African continent.