bluuebunny/crossref_metadata_2025_split huggingface dataset:
Opto-Electro-Thermal Modeling of Thin-Film Hydrogenated Amorphous Silicon (a-Si:H) Photovoltaic Cell
Authors: Lai Jia-Jiun , Wong Basil T. , Chai Jasman Y.-H. 
Published: October 2020

AbstractA one-dimensional opto-electro-thermal simulator for an a-Si:H-based thin-film solar cell is developed. The simulator includes optical, electrical, and thermal modeling for a complete modeling of energy conversion in a-Si:based solar cells. Particularly, the thermal impact on the performance of the cell has been studied. Cell performance is worse when thermal simulation is included compared to simulations where the temperature is kept constant. This implication suggests that cell performance is typically overestimated in simulations where the thermal effect is ignored. A simplified optical model was used, reducing the computational resources required in the study. The electrical model proposed in this study extends the classical drift-diffusion model to include the effects of temperature. The proposed thermal model considers the energy conservation in a non-thermal equilibrium condition between electron, optical phonons, and acoustic phonons. While simplifications have been used to reduce the complexity of the simulations, the program captures the essential behavior of the cell with reasonable accuracy. Hence, the developed program is useful for a-Si:H-based thin-film solar cell design and optimization.
Numerical Method for Direct Solution to Form-Finding Problem in Convex Gridshell
Authors: Huang Weicheng , Qin Longhui , Khalid Jawed Mohammad 
Published: October 2020

AbstractElastic gridshell is a class of net-like structure formed by an ensemble of elastically deforming rods coupled through joints, such that the structure can cover large areas with low self-weight and allow for a variety of aesthetic configurations. Gridshells, also known as X-shells or Cosserat Nets, are a planar grid of elastic rods in its undeformed configuration. The end points of the rods are constrained and positioned on a closed curve—the final boundary—to actuate the structure into a 3D shape. Here, we report a discrete differential geometry-based numerical framework to study the geometrically nonlinear deformation of gridshell structures, accounting for non-trivial bending-twisting coupling at the joints. The form-finding problem of obtaining the undeformed planar configuration given the target convex 3D topology is then investigated. For the forward (2D to 3D) physically based simulation, we decompose the gridshell structure into multiple one-dimensional elastic rods and simulate their deformation by the well-established discrete elastic rods (DER) algorithm. A simple penalty energy between rods and linkages is used to simulate the coupling between two rods at the joints. For the inverse problem associated with form-finding (3D to 2D), we introduce a contact-based algorithm between the elastic gridshell and a rigid 3D surface, where the rigid surface describes the target shape of the gridshell upon actuation. This technique removes the need of several forward simulations associated with conventional optimization algorithms and provides a direct solution to the inverse problem. Several examples—hemispherical cap, paraboloid, and hemi-ellipsoid—are used to show the effectiveness of the inverse design process.
Fluid Convection Models for Low-Temperature Grinding and Effect of Fluid Warming
Authors: Zhang Lei , Brian Rowe W. 
Published: October 2020

AbstractThe paper considers fluid convection in low-temperature grinding. Fluid cooling often predominates over all other forms of heat dispersion in the grinding zone particularly in low-temperature grinding. Experimental values of convection heat transfer coefficient (CHTC) up to and in excess of 200,000 W/m2K have been found by various researchers both for water-based emulsions and in one case for mineral oils employed in high wheel-speed grinding. Several convection models have been developed in recent years for the prediction of CHTCs in low-temperature grinding. This paper reviews advances in convection modeling and reconsiders the basic assumptions implied. A proposal is made for improved estimation for highly churned flow assuming a degree of fluid warming. Predicted coefficients are compared with measured values.
Modeling the Dynamics of Five-Axis Machine Tool Using the Multibody Approach
Authors: Huynh Hoai Nam , Altintas Yusuf 
Published: October 2020

AbstractA systematic modeling of multibody dynamics of five-axis machine tools is presented in this article. The machine is divided into major subassemblies such as spindle, column, bed, tool changer, and longitudinal and rotary drives. The inertias and mass center of each subassembly are calculated from the design model. The subassemblies are connected with elastic springs and damping elements at contact joints to form the complete multibody dynamic model of the machine that considers the rigid body kinematics and structural vibrations of the machine at any point. The unknown elastic joint parameters are estimated from the experimental modal analysis of the machine tool. The resulting position-dependent multibody dynamic model has the minimal number of degrees-of-freedom that is equivalent to the number of measured modes, as opposed to thousands used in finite element models. The frequency response functions of the machine can be predicted at any posture of the five-axis machine, which are compared against the directly measured values to assess the validity of model. The proposed model can predict the combined rigid body motion and vibrations of the machine with computational efficiency, and hence, it can be used as a digital twin to simulate its dynamic performance in machining operations and tracking control tests of the servo drives.
The diagnostic accuracy of ultrasound in the detection of foot and ankle fractures: a systematic review and meta-analysis
Authors: Wu Jiangfeng , Wang Yunlai , Wang Zhengping 
Published: October 2020

Aims: Foot and ankle injuries are a common presenting complaint in the emergency department. The diagnosis of foot and ankle fractures is conventionally accomplished through X-rays. Whether ultrasound (US) can be considered as a primary scanning modality is still a controversial issue; therefore, we did a meta-analysis to synthesize the diagnostic performance ofultrasound for foot and ankle fractures.Material and methods: A comprehensive search was carried out to identify studies in which patients with clinically suspected foot and ankle fractures were assessed by US. Two investigators independently screened the literature and extracted the data. Any discrepancies were resolved via discussion. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 tool, and pooled sensitivity and specificity of various US findings were determined.Results: Ten studies with a total of 1065 patients were included. There was significant heterogeneity across the included studies. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for the diagnosis of foot and ankle fractures by US were 0.96 (95% confidence interval [CI], 0.90-0.99), 0.94 (95% CI, 0.88-0.97), 15.0 (95% CI, 7.9-28.6), 0.04 (95% CI, 0.02-0.11), and 367 (95% CI, 101-1338), respectively. Furthermore, the summary receiver operating characteristic area under the curve was calculated to be 0.99.Conclusions: Ultrasound has an excellent diagnostic performance for foot and ankle fractures and should be considered as a primary and radiation-free scanning modality in the diagnosis of foot and ankle fractures.
Global work index by non-invasive pressure-strain loops: a novel parameter to assess left ventricular performance in the early stages of heart failure with preserved or mid-range ejection fraction after acute myocardial infarction
Authors: Tomoaia Raluca , Beyer Ruxandra Stefana , Zdrenghea Dumitru , Dadarlat-Pop Alexandra , Cismaru Gabriel , Gusetu Gabriel , Rosu Radu , Serban Adela , Pop Dana 
Published: October 2020

Aim: To determine the relationship between myocardial work (MW) indices derived from non-invasive pressure-strain loops (PSL) and established parameters of left ventricular (LV) performance in patients with acute myocardial infarction (AMI) and heart failure (HF) with preserved or mid-range ejection fraction (HFpEF/HFmrEF).Material and methods: Speckle-tracking echocardiography (STE) was used to determine MW indices and global longitudinal strain (GLS) in the first 24-48 hours after admission in patients with AMI, HF symptoms, NT-proBNP >300 pg/mL and left ventricular ejection fraction (LVEF) >40%. MW was calculated by using PSL, which combine strain and non-invasive blood pressure measurement. Global MW index (GWI) was defined as the work inside the area of the PSL.Results: Forty-nine patients (mean age 68±13 years) fulfilled the inclusion criteria. Both GWI (1057±338 mmHg%) and GLS (-10.4±3.3%) were reduced in the majority of the patients. However, a proportion of patients with abnormal GLS showed normal GWI. There was a strong inverse relationship between GWI and GLS (r=-0.81). GWI demonstrated a strong relationship with LVEF (r=0.69) and a moderate correlation to NT-proBNP (n=-0.29). NT-proBNP showed a tendency to higher values in patients with more reduced GWI (820 [590-2550] vs 707 [460-1335], p=0.17). Out of the diastolic dysfunction parameters, GWI showed moderate correlations to LA volume index (r-0.29), E/A (r=-0.23) and E/e’ (r=-0.39), which were also significantly more impaired in patients with more reduced GWI.Conclusion: Non-invasive PSL might bring further information to LVEF and GLS in patients AMI at the early stages of HFpEF/HFmrEF, since LV performance depends on both contractile properties and variations in load in the ischemic segments.
Use of Numerically Blinded Ratings of Perceived Exertion in Soccer: Assessing Concurrent and Construct Validity
Authors: Lovell Ric , Halley Sam , Siegler Jason , Wignell Tony , Coutts Aaron J. , Massard Tim 
Published: October 2020

Purpose: To examine the concurrent and construct validity of numerically blinded ratings of perceived exertion (RPEs). Methods: A total of 30 elite male youth soccer players (age 16.7 [0.5] y) were monitored during training and matches over a 17-wk in-season period. The players’ external loads were determined via raw 10-Hz global positioning system. Heart rate (HR) was collected continuously and expressed as Bannister and Edwards training impulses, and minutes >80% of the players predetermined the maximum HR by the Yo-Yo Intermittent Recovery Test Level 1. RPE was collected confidentially 10 to 15 min after training/matches using 2 methods: (1) a traditional verbal response to the 0 to 100 category-ratio “centiMax” scale (RPE) and (2) numerically blinded RPE centiMax scale (RPEblind) with the response selected manually via a 5 × 7-in tablet “slider.” The RPE and RPEblind were divided by 10 and multiplied by the duration to derive the sessional RPE. Linear mixed models compared ratings, and within-subject repeated-measures correlations assessed the sessional RPE versus HR and external load associations. Results: There were no differences between the RPE and RPEblind (0.19; 95% confidence intervals, −0.59 to 0.20 au, P = .326) or their session values (13.5; 95% confidence intervals, −17.0 to 44.0 au, P = .386), and the ratings were nearly perfectly correlated (r = .96). The associations between the sessional RPE versus HR and external load metrics were large to very large (r = .65–.81), with no differences between the RPE methods (P ≥ .50). The RPEblind also reduced verbal anchor clustering and integer bias by 11% and 50%, respectively. Conclusions: RPEblind demonstrated concurrent and construct validity versus the traditional method, and may be used in situations where practitioners have concerns regarding the authenticity of athlete ratings.
Observational study to define reference ranges for the 3% oxygen desaturation index during sleep in healthy children under 12 years using oximetry motion-resistant technology
Authors: Ong Jonathan Wen Yi , Williams Daniel , Gavlak Johanna C , Liddle Natasha , Lowe Paula , Evans Hazel J 
Published: October 2020

ObjectiveTo define reference ranges for the 3% oxygen desaturation index (DI3) in healthy children under 12 years old during sleep.DesignObservational.SettingHome.SubjectsHealthy children aged 6 months to 12 years of age.InterventionNocturnal pulse oximetry at home. Parents documented sleep times. Visi-Download software (Stowood Scientific) analysed data with artefact and wake periods removed.Main outcome measuresThe following oximetry parameters used in the assessment of sleep-disordered breathing conditions were measured: 3% (DI3) and 4% (DI4) oxygen desaturation indices—the number of times per hour where the oxygen saturation falls by at least 3% or 4% from baseline, mean saturations (SAT50), minimum saturations (SATmin), delta index 12 s (DI12s), and percentage time with saturations below 92% and 90%.ResultsSeventy-nine children underwent nocturnal home pulse oximetry, from which there were 66 studies suitable for analysis. The median values for DI3 and DI4 were 2.58 (95% CI 1.96 to 3.10) and 0.92 (95% CI 0.73 to 1.15), respectively. The 95th and 97.5th centiles for DI3 were 6.43 and 7.06, respectively, which inform our cut-off value for normality. The mean values for SAT50 and SATmin were 97.57% (95% CI 97.38% to 97.76%) and 91.09% (95% CI 90.32% to 91.86%), respectively.ConclusionIn children aged 6 months to 12 years, we define normality of the 3% oxygen desaturation index as <7 using standalone, motion-resistant pulse oximeters with short averaging times.
Nodding syndrome: bridging the gap—a scoping review protocol
Authors: De Castro Ana Cristina , Ortega-Deballon Ivan 
Published: October 2020

IntroductionNodding syndrome (NS) is an encephalopathy of unknown origin that affects children aged between 3 and 15 years old. Cases have been reported since the 1950 in Tanzania and South Sudan, the most heavily affected population is the Acholi community in Uganda. In response to the high incidence of the disease, the Ugandan Government has developed a management algorithm, but access to such measures in affected communities is limited. There is little funding for research on the disease, consequently, few studies have been conducted to date. Nevertheless, the number of scientific publications on NS has increased since 2013, reporting several aetiological hypotheses, management algorithms and cases of stigmatisation; however, none has obtained conclusive results.This document describes a protocol for a scoping review of NS to date aimed at obtaining a broad overview of the disease. The results will identify gaps in knowledge in order to better guide future research, intervention strategies, health policies in areas at risk and cooperation and development programmes.Methods and analysisTo identify the relevant data, we will conduct a literature search using the electronic databases PubMed/Medline, Embase, Social Science Citation Index Scopus, Scientific Electronic Library Online (SciELO), Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS), Social Science Citation Index Expanded and The Cochrane Library. We will also include grey literature. The search strategy will be designed by a librarian.Two members of the team will work independently to identify studies for inclusion and perform data extraction. The search results will be assessed by two independent reviewers and data from the included studies will be charted and summarised in duplicate. The data will be summarised in tables and figures to present the research landscape and describe and map gaps.Ethics and disseminationEthical approval is not required. The scoping review will adhere to the Preferred Reporting Items for Systematic Reviews andMeta-Analyses-ScR guidelines. The results will be disseminated at scientific congresses and meetings.
Promoting early treatment for mild traumatic brain injury in primary care with a guideline implementation tool: a pilot cluster randomised trial
Authors: Silverberg Noah D , Panenka William J , Lizotte Pierre-Paul , Bayley Mark T , Dance Derry , Li Linda C 
Published: October 2020

ObjectivesNew clinical practice guidelines for the management of mild traumatic brain injury (mTBI) emphasise that family physicians should proactively screen and initiate treatment for depression/anxiety, insomnia and headaches. This study aimed to evaluate the feasibility of delivering an implementation intervention to family physicians.DesignPilot cluster randomised controlled trial.SettingSpecialty outpatient clinic (recruitment) and primary care (implementation).Participants114 primary care clinics were randomised. These clinics were associated with 137 unique family physicians caring for 148 adult patients who sustained an mTBI within the previous 3 months and were seeking care for persistent symptoms.InterventionsPatients completed self-report screening measures for depression/anxiety, insomnia and headaches. A tailored letter that incorporates the patient’s screening test results and associated treatment algorithms was sent to their family physician (or walk-in clinic). Physicians at clinics assigned to the control condition received a generic letter, without the screening test results.Primary outcome measuresFeasibility outcomes included the frequency of primary care follow-up, retention rates and reliability of patient recall of their physicians’ actions (primary mechanistic outcome). The primary efficacy outcome was the Rivermead Post-Concussion Symptom Questionnaire (RPQ).ResultsMost patients (97.8%; 128 of 131) followed up at the primary care clinic they planned to. Retention rates were 88% (131 of 148) and 78% (116 of 148) at the 1-month and 3-month assessments, respectively. Agreement between patient recall of their physicians’ actions and medical chart audits was moderate (intraclass correlation coefficient=0.48–0.65). Patients in the experimental group reported fewer symptoms on the RPQ compared with those in the control group, whose physician received a general letter (B=−4.0, 95% CI: −7.3 to −0.7).ConclusionsA larger trial will need to address minor feasibility challenges to evaluate the effectiveness of this guideline implementation tool for improving mTBI clinical outcomes and confirm the mechanism(s) of intervention benefit.Trial registration numberNCT03221218.
Developing core economic parameter sets for asthma studies: a realist review and an analytical framework
Authors: Roukas Chris , Quayyum Zahidul , Patel Anita , Fitzsimmons Deborah , Phillips Ceri , Hounsome Natalia 
Published: October 2020

ObjectiveTo develop a standardised set of economic parameters (core economic parameter set) for economic evaluations in asthma studies.DesignA systematic literature review and an analytical framework.Outcome measuresEconomic parameters used to evaluate costs and cost-effectiveness of healthcare interventions for people with asthma.Data sourcesPubMed, the Cochrane Database of Systematic Reviews, the National Health Service Economic Evaluation Database, the Database of Abstracts of Reviews of Effects and the Health Technology Aaaessment Library starting from 1990.Review methodsResearch methods were based on the realist review methodology and included a number of non-sequential, iterative and overlapping components, such as developing an analytical framework for the realist review; systematic literature review of economic parameters; identifying and categorising economic parameters; producing preliminary list of core economic parameters.ResultsDatabase searches found 2531 publications of which 224 were included in the systematic review. We identified 65 economic parameters that were categorised into 11 groups to enable the realist synthesis. Parameters related to secondary care, primary care, medication use, emergency care and work productivity comprised 84% of all economic parameters. An analytical framework was used to investigate the rationale behind the choices of economic parameters in these studies. The main framework domains included type of intervention, research population, study design, study setting and a stakeholder’s perspective.ConclusionPast research thus suggests that in asthma study parameters depicting the use of secondary care, primary care, medication, emergency care and work productivity can be considered as core economic parameters, since they apply to different types of studies. Parameters including diagnostics, healthcare delivery, school activity, informal care, medical devices and health utility apply to a particular type of study (or research question), and thus can be recommended as supplemental parameters.PROSPERO registration numberCRD42017067867.
Variation in the design of Do Not Resuscitate orders and other code status options: a multi-institutional qualitative study
Authors: Batten Jason N , Blythe Jacob A , Wieten Sarah , Cotler Miriam Piven , Kayser Joshua B , Porter-Williamson Karin , Harman Stephanie , Dzeng Elizabeth , Magnus David 
Published: October 2020

BackgroundUS hospitals typically provide a set of code status options that includes Full Code and Do Not Resuscitate (DNR) but often includes additional options. Although US hospitals differ in the design of code status options, this variation and its impacts have not been empirically studied.Design and methodsMulti-institutional qualitative study at 7 US hospitals selected for variability in geographical location, type of institution and design of code status options. We triangulated across three data sources (policy documents, code status ordering menus and in-depth physician interviews) to characterise the code status options available at each hospital. Using inductive qualitative methods, we investigated design differences in hospital code status options and the perceived impacts of these differences.ResultsThe code status options at each hospital varied widely with regard to the number of code status options, the names and definitions of code status options, and the formatting and capabilities of code status ordering menus. DNR orders were named and defined differently at each hospital studied. We identified five key design characteristics that impact the function of a code status order. Each hospital’s code status options were unique with respect to these characteristics, indicating that code status plays differing roles in each hospital. Physician participants perceived that the design of code status options shapes communication and decision-making practices about resuscitation and life-sustaining treatments, especially at the end of life. We identified four potential mechanisms through which this may occur: framing conversations, prompting decisions, shaping inferences and creating categories.ConclusionsThere are substantive differences in the design of hospital code status options that may contribute to known variability in end-of-life care and treatment intensity among US hospitals. Our framework can be used to design hospital code status options or evaluate their function.